Objective To examine the effect of neuropeptide Y (NPY) on TGF-β1 production in RAW264.7 macrophages. Methods Enzyme linked immunosorbent assay (ELISA) was used to detect TGF-β1 production. Cell counting kit 8 ...Objective To examine the effect of neuropeptide Y (NPY) on TGF-β1 production in RAW264.7 macrophages. Methods Enzyme linked immunosorbent assay (ELISA) was used to detect TGF-β1 production. Cell counting kit 8 (CCK-8) was used to assay the viability of RAW264.7 cells. Western blot was used to detect the phosphorylation of PI3K p85. Results NPY treatment could promote TGF-β1 production and rapid phosphorylation of PI3K p85 in RAW264.7 cells via Y1 receptor. The elevated TGF-β 1 production induced by NPY could be abolished by wortrnannin pretreatment. Conclusion NPY may elicit TGF-β production in RAW264.7 cells via Y1 receptor, and the activated PI3K pathway may account for this effect.展开更多
Objective: To investigate the influence of central administration ofneuropeptide Y-Y5 receptor antisense oligodeoxynucleotides (ODNs) on body weight, fat pads of SDrats, and the effects of white adipocytes lipolysis a...Objective: To investigate the influence of central administration ofneuropeptide Y-Y5 receptor antisense oligodeoxynucleotides (ODNs) on body weight, fat pads of SDrats, and the effects of white adipocytes lipolysis and apoptosis. Methods: Y5 receptor antisense,sense, mismatched ODNs or vehicle was intracerebroventricularly (i. c. v.) injected. Averageadipocyte area was calculated. DNA ladders were measured to evaluate adipocyte apoptosis, and RT-PCRwas used to analyse the expression of Bcl-2 and Bax gene. Results: Central administration of Y5antisense ODNs significantly decreased body weight, and average adipocyte area. DNA fragmentationwas present after electrophoresis at epididymal adipose tissue. The expression of Bcl-2 gene wasdownregulated, while the expression of Bax upregulated. Conclusion: Lipolysis and adipocyteapoptosis may be important mechanisms far 75 antisense therapy.展开更多
Objective: To study the efficacy of antisense oligonucleotide of neuropeptide Y (NPY) Y5 receptor on treating hyperleptinemia by intracerebral ventricular administration in diet-induced obese rats.Methods: The obese r...Objective: To study the efficacy of antisense oligonucleotide of neuropeptide Y (NPY) Y5 receptor on treating hyperleptinemia by intracerebral ventricular administration in diet-induced obese rats.Methods: The obese rats were prepared by feeding a high-nutritive diet for 7 weeks. The lateral ventricle of obese rats was cannulated. Either 10 μl of different neuropeptide Y Y5 receptor oligodeoxynucleotide, including antisense, sense and missense oligodeoxynucleotide (5 g/L) or 10 μl saline was administered into the ventricle through cannula three times per day in every rat. Two days later the rats were slaughtered .The weights of both retroperitoneal and epididymal adipose tissues were measured, and the serum insulin and leptin were detected by radioimmunoassay method and the murine leptin ELISA kit respectively. Results: ①The level of serum was significantly higher in experimental rats than that in normal rats. Similarly, the level of serum insulin and the weights of both retroperitoneal and epididymal adipose tissues were increased in experimental rats. ②After the diet-induced obese rats were intraventricularly administered with NPY Y5 receptor antisense oligodeoxynucleotide, the levels of serum leptin and insulin were significantly decreased and combined with the reduction of weight in retroperitoneal adipose tissue. There was, however, no significant difference in the weight of epidymal adipose tissue between pre-treated and post-treated duration. ③There was significant positive correlation among the level of serum leptin, the level of serum insulin and the weight of retroperritoneal adipose tissue in diet-induced obese rats. Conclusion: Intracerebral ventricular administration of antisense oligodeoxynucleotide of neuropeptide Y Y5 receptor may alleviate hyperleptinemia in diet-induced obese rats and decrease the weight of retroperitoneal adipose tissue and the level of serum insulin.展开更多
In this study, Sprague-Dawley rats were immobilized to a frame for 3 hours a day for 21 days to establish a model of chronic immobilization stress. The body weight and food intake of rats subjected to chronic immobili...In this study, Sprague-Dawley rats were immobilized to a frame for 3 hours a day for 21 days to establish a model of chronic immobilization stress. The body weight and food intake of rats subjected to chronic immobilization stress were significantly decreased compared with the control group. Dual-labeling immunofluorescence revealed that the expression of leptin receptor and the co-localization coeffient in these leptic receptor neurons in the arcuate nucleus of the hypothalamus were both upregulated, while the number of neuropeptide Y neurons was decreased. Chronic immobilization stress induced high expression of leptin receptor in the arcuate nucleus and suppressed the synthesis and secretion of neuropeptide Y, thereby disrupting the pathways in the arcuate nucleus that regulate feeding behavior, resulting in diminished food intake and reduced body weight.展开更多
Objective: To study the role of β3-adrenergic receptor gene in neuropeptide Y(NPY) Y5 receptor antisense gene therapy of diet-induced obese rats.Methods: The diet-induced obese rats were prepared by feeding a high-nu...Objective: To study the role of β3-adrenergic receptor gene in neuropeptide Y(NPY) Y5 receptor antisense gene therapy of diet-induced obese rats.Methods: The diet-induced obese rats were prepared by feeding a high-nutrition diet. Lateral ventricular was cannulated in obese rats which then received an intraventricular injection of either 5 μg/μl NPY Y5 receptor antisense or 10 μl missense oligodeoxynucleotide or saline of 10 μl respectively in every rat. When the rats were killed, the wet weight of abdominal adipose tissue, the level of serum lipid and lipoprotein were measured. Total RNA from the retroperitoneal adipose tissue was extracted and the level of β3-adrenergic receptor gene mRNA expression was evaluated by RT-PCR.Results: ①The wet weight of abdominal adipose tissue, the levels of serum lipids were greatly higher in diet-induced obese rats than those in normal rats. However, there were much lower β3-adrenergic receptor gene mRNA expression levels in retroperitoneal adipose tissue in diet-induced obese rats as compared with those in normal rats. ②After the diet-induced obese rats were intraventricularly administered with NPY Y5 receptor antisense oligodeoxynucleotide, the levels of β3-adrenergic receptor gene mRNA expression in retroperitoneal adipose tissue of diet-induced obese rats were strikingly up-regulated, whereas the wet weight of abdominal adipose tissue, the levels of serum lipids were markedly reduced.Conclusion: Intraventricular administration of antisense oligodeoxynucleotide to NPY Y5 receptor could significantly reduce the abdominal adipose tissue and the levels of serum lipids in diet-induced obese rats by up-regulating the level of β3-adrenergic receptor gene mRNA expression in retroperitoneal adipose tissue.展开更多
AIM: To explore the mechanism for interactions of leptin with ghrelin and orexin in the arcuate nucleus (ARC) activating neuropeptide Y (NPY) neurons during physiological regulation of feeding, METHODS: Single n...AIM: To explore the mechanism for interactions of leptin with ghrelin and orexin in the arcuate nucleus (ARC) activating neuropeptide Y (NPY) neurons during physiological regulation of feeding, METHODS: Single neurons from ARC of adult rats with matured feeding function were isolated. [Ca2+]i was measured to monitore their activities. The time course of leptin effects on ghrelin-induced versus orexin-induced [Ca2+]i increases in NPY neurons was studied. RESULTS: Administration of ghrelin or orexin-A at 101~ mol/L increased cytosolic Ca2~ concentration ([Ca2+]~) in NPY neurons isolated from the ARC of adult rats. Upon administration of leptin at 10^-14-10^-12 mol/L, ghrelin-induced [Ca2+]i increases were initially (〈 10 min) inhibited but later restored, exhibiting a transient pattern of inhibition. In contrast, orexin-induced [Ca2+]i increases were inhibited by leptin in a long- lasting manner. Furthermore, a prior administration of leptin inhibited orexin action but not ghrelin action to increase ICa 2+li, CONCLUSION: Leptin counteracted ghrelin effects transiently and orexin effects long-lastingly in NPY neurons. The transient property with which leptin counteracts ghrelin action in NPY neurons may allow the fasting-associated increase in ghrelin levels to activate NPY neurons in the presence of physiological leptin and to stimulate feeding.展开更多
BACKGROUND: It is known that acupuncture therapy can decrease plasma neuropeptide Y (NPY) levels in patients with cerebral infarction, but different types of acupuncture therapy used in various stages of cerebral i...BACKGROUND: It is known that acupuncture therapy can decrease plasma neuropeptide Y (NPY) levels in patients with cerebral infarction, but different types of acupuncture therapy used in various stages of cerebral infarction have not been evaluated. OBJECTIVE: To explore the effect of acupuncture therapy on resuscitation (Xingnao Kaiqiao) and plasma NPY levels in patients with very early stage acute cerebral infarction. DESIGN, TIME AND SETTING: This case-controlled study was performed at the Affiliated Hospital of the Medical College of the Chinese People's Armed Police Force between September 2004 and October 2005. PARTICIPANTS: Sixty patients with acute cerebral infarction of ≤ 6 hours were used in this study. Patients were randomly divided into an acupuncture therapy group (n = 30) and a routine treatment group (n = 30). Another 30 healthy subjects were used as the control group. METHODS: The acupuncture therapy of Xingnao Kaiqiao used in the acupuncture therapy group was based on routine western medical treatment and was performed at bilateral Neiguan (PCG) using the twirling, reinforcing-reducing method, Renzhong (DU26) using heavy bird-pecking needling, Sanyinjiao (SPG) using reinforcing and reducing by lifting and thrusting the needle, Jiquan (HT1), Weizhong (BL40) and Chize (LU5) using reinforcing and reducing by lifting and thrusting the needle. The acupuncture lasted for 14 days. Patients in the routine treatment group underwent routine medical treatment and no intervention was given to subjects in the control group. MAIN OUTCOME MEASURES: A 4 mL venous blood sample was obtained at different time points, i.e., immediately after hospitalization, the next morning, 7 and 14 days after treatment, to measure plasma NPY levels pre- and post-treatment using the radio-immunity method. RESULTS: The plasma NPY levels were significantly higher in both the routine treatment group and the acupuncture therapy group than in the control group pre- and post-treatment (P 〈 0.01). In particular, the plasma NPY levels in both the acupuncture therapy group and the routine treatment group were increased 7 days post-treatment but decreased from 7-14 days post-treatment. In addition, the plasma NPY levels were significantly lower in the acupuncture therapy group than in the routine treatment group on day 7 and 14 post-treatment (P 〈 0.01). CONCLUSION: Acupuncture therapy of Xingnao Kaiqiao can decrease plasma NPY levels in patients with very early stage acute cerebral infarction. In addition, the therapeutic effect of acupuncture with a prolonged therapy time is superior to routine treatment.展开更多
BACKGROUND: Previous research has revealed that somatostatin can induce epilepsy, and that the levels of neuropeptide Y may increase and become more active in brain areas with epileptic seizures. OBJECTIVE: To obser...BACKGROUND: Previous research has revealed that somatostatin can induce epilepsy, and that the levels of neuropeptide Y may increase and become more active in brain areas with epileptic seizures. OBJECTIVE: To observe the effect of Ganoderma luciclum spore powder on the neuropeptide Y and somatostatin content in the cerebral cortex and hippocampal regions of seizure rats induced by pentylenetetrazol (PTZ). Furthermore, to verify any effect of Ganoderma lucidum spore powder on inhibition of epileptic seizures. DESIGN, TIME AND SETTING: A randomized group animal study was performed in August 2007 in the School of Basic Medical Sciences, Jiamusi University (Jiamusi, Heilongjiang, China). MATERIALS: Thirty healthy, male, Wistar rats, aged 12 weeks and weighing 180-220 g, were taken as the experimental animals. PTZ (Sigma Company, United States) was used to induce epilepsy. Ganoderma lucidum spores (Leyss, ex Fr variety) were purchased from Jiamusi City Wild Growing Case of the Ganoderma Lucidum (China). Rabbit anti-somatostatin antibodies and secondary antibodies were purchased from Wuhan Boster Company (China). Neuropeptide Y radioimmunoassay kit was purchased from Beijing Furui Biotechnology Company (China). METHODS: Thirty rats were randomly divided into three groups: a control group, an epilepsy model group and a Ganoderma lucidum spore-treated group. Each group contained 10 animals. Rats in the epilepsy model group were treated with intraperitoneal injections of PTZ and gastric perfusion of physiologic saline. In the Ganoderma lucidum spore-treated group, intraperitoneal injection of PTZ and gastric perfusion of Ganoderma lucidum spore powder were administered. The blank control group was only administered with the physiological saline by intraperitoneal injection and gastric perfusion. MAIN OUTCOME MEASURES: Immunohistochemical staining and radioimmunoassay methods were used to observe the changes of somatostatin and neuropeptide Y content in brain tissue of epileptic rats, as well as the morphology of neurons. RESULTS: All 30 rats were involved in the result analysis, without any loss. The number of somatostatin immunoreacted positive cells in the cerebral cortex and hippocampus was significantly increased in the epilepsy model group compared to the blank control group (P 〈 0.01). The number of somatostatin immunoreacted positive cells in cerebral cortex and hippocampus was significantly decreased in the Ganoderma lucidum spore-treated group compared to the epilepsy model group (P 〈 0.01). The contents of neuropeptide Y in cerebral cortex and hippocampus were significantly increased in the epilepsy model group compared to the blank control group (P 〈 0.01). The contents of neuropeptide Y in the cerebral cortex and hippocampus were significantly decreased in the Ganoderma lucidum spore-treated group compared to the epilepsy model group (P 〈 0.05). The epilepsy seizures in the Ganoderma lucidum spore-treated group were obviously reduced compared to the epilepsy model group. CONCLUSION: Ganoderma lucidum spore powder was able to reduce the somatostatin and neuropeptide Y content in the cerebral cortex and hippocampus effectively, so as to achieve an anti-epileptic function and protect neurons from being damaged.展开更多
Neuropeptide Y (NPY) is one of the most important orexigenic agents in central regulation of feeding behavior, body weight and energy homeostasis in domestic chickens. To examine differences in the hypothalamic NPY ...Neuropeptide Y (NPY) is one of the most important orexigenic agents in central regulation of feeding behavior, body weight and energy homeostasis in domestic chickens. To examine differences in the hypothalamic NPY between layer-type and meat-type of chickens, which are two divergent kinds of the domestic chickens in feeding behavior and body weight, we detected mRNA levels of NPY in hypothalamic infundibular nucleus (IN), paraventricular nucleus (PVN) and lateral hypothalamic area (LHA) of these two types of chickens using one-step real time RT-PCR. The meat-type chicken had more food daily (about 1.7 folds) and greater body weights (about 1.5 folds) and brain weights than the layer-type chicken at the age of 14 d. In the meat-type of chicken, NPY mRNA levels of the IN and PVN were significantly greater than those of the LHA, and were not significantly different between the lN and PVN. However, in the layer-type of chicken, NPY mRNA levels were significantly greater in the IN than those in the LHA and PVN, and were not significantly different between the PVN and LHA. In all these hypothalamic regions the layer-type of chicken had significantly higher NPY mRNA levels than the meat-type chicken did. These results suggest the expression of NPY in the hypothalamus has a type-dependent pattern in domestic chickens.展开更多
Neuropeptide Y gene transfection into normal rat brain tissue can provide gene overexpression, which can attenuate the severity of kainic acid-induced seizures. In this study, a recombinant adeno-associated virus carr...Neuropeptide Y gene transfection into normal rat brain tissue can provide gene overexpression, which can attenuate the severity of kainic acid-induced seizures. In this study, a recombinant adeno-associated virus carrying the neuropeptide Y gene was transfected into brain tissue of rats with kainic acid-induced epilepsy through stereotactic methods. Following these transfections, we verified overexpression of the neuropeptide Y gene in the epileptic brain. Electroencephalograms showed that seizure severity was significantly inhibited and seizure latency was significantly prolonged up to 4 weeks after gene transfection. Moreover, quantitative fluorescent PCR and western blot assays revealed that the mRNA and protein expression of the N-methyI-D-aspartate receptor subunits NR1, NR2A, and NR2B was inhibited in the hippocampus of epileptic rats. These findings indicate that neuropeptide Y may inhibit seizures via down-regulation of the functional expression of N-methyI-D-aspartate receptors.展开更多
Exogenous neuropeptide Y has antiepileptic effects; however, the underlying mechanism and optimal administration method for neuropeptide Y are still unresolved. Previous studies have used intracerebroventricular injec...Exogenous neuropeptide Y has antiepileptic effects; however, the underlying mechanism and optimal administration method for neuropeptide Y are still unresolved. Previous studies have used intracerebroventricular injection of neuropeptide Y into animal models of epilepsy. In this study, a recombinant adeno-associated virus expression vector carrying the neuropeptide Y gene was injected into the lateral ventricle of rats, while the ipsilateral hippocampus was injected with kainic acid to establish the epileptic model. After transfection of neuropeptide Y gene, mossy fiber sprouting in the hippocampal CA3 region of epileptic rats was significantly suppressed, hippocampal synaptophysin (p38) mRNA and protein expression were inhibited, and epileptic seizures were reduced. These experimental findings indicate that a recombinant adeno-associated virus expression vector carrying the neuropeptide Y gene reduces mossy fiber sprouting and inhibits abnormal synaptophysin expression, thereby suppressing post-epileptic synaptic reconstruction.展开更多
Metformin may reduce food intake and body weight, but the anorexigenic effects of metformin are still poorly understood. In this study, Sprague-Dawley rats were administered a single intracere- broventricular dose of ...Metformin may reduce food intake and body weight, but the anorexigenic effects of metformin are still poorly understood. In this study, Sprague-Dawley rats were administered a single intracere- broventricular dose of metformin and compound C, in a broader attempt to investigate the regula- tory effects of metformin on food intake and to explore the possible mechanism. Results showed that central administration of metformin significantly reduced food intake and body weight gain, par- ticularly after 4 hours. A reduction of neuropeptide Y expression and induction of AMP-activated protein kinase phosphorylation in the hypothalamus were also observed 4 hours after metformin administration, which could be reversed by compound C, a commonly-used antagonist of AMP-activated protein kinase. Furthermore, metformin also improved lipid metabolism by reducing plasma low-density lipoprotein. Our findings suggest that under normal physiological conditions, central regulation of appetite by metformin is related to a decrease in neuropeptide Y gene expres- sion, and that the activation of AMP-activated protein kinase may simply be a response to the anorexigenic effect of metformin.展开更多
OBJECTIVE Neuropeptide Y (NPY) acts as a neuroendocrine modulator in the anterior pituitary, and NPY mRNA and NPY-immunoreactivity have been detected in normal human anterior pituitaries. However, only a few studies...OBJECTIVE Neuropeptide Y (NPY) acts as a neuroendocrine modulator in the anterior pituitary, and NPY mRNA and NPY-immunoreactivity have been detected in normal human anterior pituitaries. However, only a few studies of NPY expression in human pituitary adenomas have been published. Our study was conducted to determine whether or not adenomatous cells express NPY, to investigate the relationship between NPY expression and the subtypes of pituitary adenoma and to explore the clinical significance of NPY. METHODS The study included tissues from 58 patients with pituitary adenomas who underwent surgery because of their clinical diagnosis. Using a highly specific anti-NPY polyclonal antibody, immunohistochemical analysis was performed on the surgically removed pituitary adenomas. Six fresh specimens also were examined using immuno-electron microscopy. NPY was labeled with colloidal gold in order to study the distribution of NPY at the subcellular level. RESULTS The NPY expression level was significantly different among subgroups of pituitary adenomas (P〈0.05). NPY was immuno-detected in 58.6% of all adenomas, in 91.7% of gonadotrophic adenomas and in 14.3% of prolactinomas. NPY expression was slightly lower in invasive pituitary adenomas compared to noninvasive adenomas, but the difference was not significant (t=1.81, P〉0.05). Of particular interest was the finding that vascular endothelial cells showed positive NPY expression in some pituitary adenomas. Parts of strongly positive tumor cells were seen in channels formed without endothelial cells, but which contained some red blood cells in a formation similar to so-called vasculogenic mimicry. Immuno-electron microscopy demonstrated that 4 of the 6 fresh specimens displayed positive NPY staining with a high density of gold particles located mainly in the secretory granulas. In addition, gold particles were sparsely detected in the rough endoplasmic reticulum and cell matrix. CONCLUSION NPY exists in pituitary adenomas and its expression level was related to the types and biological characteristics of the pituitary adenomas. NPY may have a depressive effect on tumor cellular proliferation in pituitary adenomas. NPY possibly participates in modulating angiogenesis and hemodynamic changes in pituitary adenomas.展开更多
Neuropeptide Y has been shown to inhibit the immunological activity of reactive microglia in the rat cerebral cortex, to reduce N-methyl-D-aspartate current(INMDA) in cortical neurons, and protect neurons. In this s...Neuropeptide Y has been shown to inhibit the immunological activity of reactive microglia in the rat cerebral cortex, to reduce N-methyl-D-aspartate current(INMDA) in cortical neurons, and protect neurons. In this study, after primary cultured microglia from the cerebral cortex of rats were treated with lipopolysaccharide, interleukin-1β and tumor necrosis factor-α levels in the cell culture medium increased, and mRNA expression of these cytokines also increased. After primary cultured cortical neurons were incubated with the lipopolysaccharide-treated microglial conditioned medium, peak INMDA in neurons increased. These effects of lipopolysaccharide were suppressed by neuropeptide Y. After addition of the neuropeptide Y Y1 receptor antagonist BIBP3226, the effects of neuropeptide Y completely disappeared. These results suggest that neuropeptide Y prevents excessive production of interleukin-1β and tumor necrosis factor-α by inhibiting microglial reactivity. This reduces INMDA in rat cortical neurons, preventing excitotoxicity, thereby protecting neurons.展开更多
Our preliminary study demonstrated that neuropeptide Y (NPY)/nestin-positive cells exhibit a consistent spatial distribution in the hippocampus of normal adult rats. However, following severe acute and chronic stres...Our preliminary study demonstrated that neuropeptide Y (NPY)/nestin-positive cells exhibit a consistent spatial distribution in the hippocampus of normal adult rats. However, following severe acute and chronic stress-induced impaired learning and memory, synchronous decreased expression of nestin and NPY takes place in the hippocampus, and the underlying mechanisms remain unclear. In the present study, acute and chronic stress rat models were established using combined restrained and inverted stress. Results showed that learning and memory significantly decreased in acute and chronic stress rats. In addition, hippocampal cells were damaged, in particular in the acute stress rats, and nestin and NPY expression, as well as the number of NPY/nestin-positive cells in the CA3 region, significantly decreased. Furthermore, mature neurofilament 200-positive neurons were absent in the chronic stress rats. The NPY and cytoskeletal protein system equally contributed to stress-induced early learning and memory deficits as well as sustained cerebral iniurv in the adult hippocampus.展开更多
Musculoskeletal disorders are the leading causes of disability and result in reduced quality of life.The neuro-osteogenic network is one of the most promising fields in orthopaedic research.Neuropeptide Y(NPY)system h...Musculoskeletal disorders are the leading causes of disability and result in reduced quality of life.The neuro-osteogenic network is one of the most promising fields in orthopaedic research.Neuropeptide Y(NPY)system has been reported to be involved in the regulations of bone metabolism and homeostasis,which also provide feedback to the central NPY system via NPY receptors.Currently,potential roles of peripheral NPY in bone metabolism remain unclear.Growing evidence suggests that NPY can regulate biological actions of bone marrow mesenchymal stem cells,hematopoietic stem cells,endothelial cells,and chondrocytes via a local autocrine or paracrine manner by different NPY receptors.The regulative activities of NPY may be achieved through the plasticity of NPY receptors,and interactions among the targeted cells as well.In general,NPY can influence proliferation,apoptosis,differentiation,migration,mobilization,and cytokine secretion of different types of cells,and play crucial roles in the development of bone delayed/non-union,osteoporosis,and osteoarthritis.Further basic research should clarify detailed mechanisms of action of NPY on stem cells,and clinical investigations are also necessary to comprehensively evaluate potential applications of NPY and its receptor-targeted drugs in management of musculoskeletal disorders.展开更多
Neuropeptide Y(NPY) is a 36-amino acid peptide of the neuropeptide Y family that plays key roles in the regulation of food intake. In this study,we focused on NPY m RNA expression changes around feeding time and durin...Neuropeptide Y(NPY) is a 36-amino acid peptide of the neuropeptide Y family that plays key roles in the regulation of food intake. In this study,we focused on NPY m RNA expression changes around feeding time and during food deprivation in olive flounder. The olive flounder NPY m RNA levels were analyzed in different tissues and a high level of expression was detected in the brain. We also demonstrated a correlation between NPY expression levels in the brain and feeding schedule. NPY expression levels in olive flounder maintained on a daily scheduled feeding regimen increased shortly before feeding and decreased after the scheduled feeding time. Compared with the-1 h group before feeding,NPY expression in the 3 h group after feeding decreased significantly( P <0.05). Food deprivation led to an 81.7% decrease in NPY m RNA levels in the 24 h fasted group(P <0.05) and a 91.7% decrease in the 48 h fasted group(P <0.05). Therefore,our study demonstrates that NPY expression is associated with food intake in olive flounder. This result reveals the function of NPY in regulating food intake and its potential importance in olive flounder aquaculture.展开更多
Neuropeptide Y (NPY) is a potent neurotransmitter for feeding. Besides NPY, orexigenic neuropeptides such as agouti-related protein (AgRP), and anorexi- genic neuropeptides such as α-melatonin stimulating hormone (MS...Neuropeptide Y (NPY) is a potent neurotransmitter for feeding. Besides NPY, orexigenic neuropeptides such as agouti-related protein (AgRP), and anorexi- genic neuropeptides such as α-melatonin stimulating hormone (MSH) and cocaine-amphetamine-regulated transcript (CART) are also involved in central feeding regulation. During fasting, NPY and AgRP gene expressions are up-regulated and POMC and CART gene ex- pressions are down-regulated in hypothalamus. Based on the network of peptidergic neurons, the former are involved in positive feeding regulation, and the latter are involved in negative feeding, which exert these feeding-regulated peptides especially in paraventricular nucleus (PVN). To clarify the compensatory mecha- nism of knock-out of NPY system on feeding, change in gene expressions of appetite-related neuropeptides and the feeding behavior was studied in NPY Y5-KO mice. Food intake was increased in Y5-KO mice. Fasting increased the amounts of food and water intake in the KO mice more profoundly. These data indicated the compensatory phenomenon of feeding behavior in Y5-KO mice. RT-PCR and ISH suggested that the compensation of feeding is due to change in gene expressions of AgRP, CART and POMC in hypothalamus. Thus, these fi ndings indicated that the compensatory mechanism involves change in POMC/CART gene expression in arcuate nucleus (ARC). The POMC/CART gene expression is important for central compensatory regulation in feeding behavior.展开更多
BACKGROUND: Neuropeptide Y (NPY) may influence differentiation of Th cells immunological pathology of experimental allergic encephalomyelitis (EAE) is differentiation of Th cells It is assumed that the related to...BACKGROUND: Neuropeptide Y (NPY) may influence differentiation of Th cells immunological pathology of experimental allergic encephalomyelitis (EAE) is differentiation of Th cells It is assumed that the related to abnormal OBJECTIVE: To investigate the effect of NPY on white matter demyelination, the serum levels interleukin-4 (IL-4) and gamma-interferon (IFN-γ ), as well as EAE pathogenesis in an EAE guinea pig model following NPY injection into the lateral cerebral ventricle. DESIGN, TIME AND SETTING: A randomized controlled animal study, which was performed in the Infection Immunity Animal Laboratory, Affiliated Hospital of Luzhou Medical College, China, from October 2005 to April 2006. MATERIALS: Thirty healthy female guinea pigs of 8-12 weeks of age, and 10 healthy female rats of three months of age were used. NPY was provided by Sigma Company, USA. NPY kit was provided by Beijing Huaying Biotechnology Institute, China. METHODS: Thirty guinea pigs were randomly divided into three groups: normal control group, EAE model group, and NPY intervention group (n =10 per group). Normal control group and EAE model group: Saline (10μ L, once) was injected into the lateral cerebral ventricle. After one week, the same volume of Freund's adjuvant complete was either injected subcutaneously into two post-palms or EAE was modeled. NPY intervention group: EAE was modeled after one week and NPY was injected (10 μ L of 6 nmol NPY, once) into the lateral cerebral ventricle. Myelin basic protein (MBP) antigen made from rat spinal cord homogenate and Freund's adjuvant complete were injected subcutaneously into both post-palms (0.2 mL per palm) to establish the EAE model. MAIN OUTCOME MEASURES: White matter demyelination of the cerebrum, cerebellum, brain stem, and spinal cord were observed by light microscopy after HE staining. Levels of serum IFN-γ and IL-4 were detected by the double antibody sandwich ABC-ELISA technique. NPY content was detected by radioimmunoassay. RESULTS: Pathological alterations in the NPY intervention groups were reduced compared to those in the EAE model group, suggesting a reduction and remission of white matter demyelination with NPY treatment. When compared to the model group, the serum IL-4 level was increased in the NPY intervention group during the high-frequent EAE stage (P 〈 0.01), but the serum IFN-γ level was decreased (P 〈 0.01). Furthermore, the EAE latency was prolonged (P 〈 0.01), the neurological scores were decreased in the high-frequent EAE stage (P 〈 0.01), and the death rate was decreased (P 〈 0.05). NPY content and the serum IL-4 level at the peak stage were positively correlated with those in the latent phase (r =0.863-0.900, P 〈 0.01), but negatively correlated with neurological scores at the peak stage (r=- -0.068 to -0.863, P 〈 0.05-0.01). The IFN-γ level at the peak stage was negatively correlated to that in the latent phase (r = -0.683-0.650, P 〈 0.05), but positively correlated to neurological scores at the peak stage (r =0.975, 0.845, P 〈 0.05). CONCLUSION: NPY injection into the lateral cerebral ventricle can promote the secretion of IL-4, inhibit the production of IFN-γ, relieve white matter demyelination, and inhibit EAE attack in an experimental model of EAE.展开更多
Death following situations of intense emotional stress has been linked to the cardiac pathology described as stress cardiomyopathy, whose pathomechanism is still not clear. In this study, we sought to determine, via a...Death following situations of intense emotional stress has been linked to the cardiac pathology described as stress cardiomyopathy, whose pathomechanism is still not clear. In this study, we sought to determine, via an animal model, whether the transcriptional coactivator peroxisome proliferator-activated receptor γ coactivator-1alpha (PGC-1α) and the amino peptide neuropeptide Y (NPY) play a role in the pathogenesis of this cardiac entity. Male Sprague-Dawley rats in the experimental group were subjected to immobilization in a plexy glass box for 1 h, which was followed by low voltage elec-tric foot shock for about 1h at 10s intervals in a cage fitted with metallic rods. After 25 days the rats were sacrificed and sections of their hearts were processed. Hematoxylin-eosin staining of cardiac tissues revealed the characteristic cardiac lesions of stress cardiomyopathy such as contraction band necrosis, inflammatory cell infiltration and fibrosis. The semi-quantitative RT-PCR analysis for PGC-1α mRNA expression showed significant overexpression of PGC1-α in the stress-subjected rats (P<0.05). Fluorescence immunohistochemistry revealed a higher production of NPY in the stress-subjected rats as compared to the control rats (P=0.0027). Thus, we are led to conclude that following periods of intense stress, an increased expression of PGC1-α in the heart and an overflow of NPY may lead to stress car-diomyopathy and even death in susceptible victims. Moreover, these markers can be used to identify stress cardiomyopathy as the cause of sudden death in specific cases.展开更多
文摘Objective To examine the effect of neuropeptide Y (NPY) on TGF-β1 production in RAW264.7 macrophages. Methods Enzyme linked immunosorbent assay (ELISA) was used to detect TGF-β1 production. Cell counting kit 8 (CCK-8) was used to assay the viability of RAW264.7 cells. Western blot was used to detect the phosphorylation of PI3K p85. Results NPY treatment could promote TGF-β1 production and rapid phosphorylation of PI3K p85 in RAW264.7 cells via Y1 receptor. The elevated TGF-β 1 production induced by NPY could be abolished by wortrnannin pretreatment. Conclusion NPY may elicit TGF-β production in RAW264.7 cells via Y1 receptor, and the activated PI3K pathway may account for this effect.
基金Supported by grant from National Natural Science Foundation (39870362)Natural Science Foundation of Education Committee of Jiangsu Province (98KJB320002).
文摘Objective: To investigate the influence of central administration ofneuropeptide Y-Y5 receptor antisense oligodeoxynucleotides (ODNs) on body weight, fat pads of SDrats, and the effects of white adipocytes lipolysis and apoptosis. Methods: Y5 receptor antisense,sense, mismatched ODNs or vehicle was intracerebroventricularly (i. c. v.) injected. Averageadipocyte area was calculated. DNA ladders were measured to evaluate adipocyte apoptosis, and RT-PCRwas used to analyse the expression of Bcl-2 and Bax gene. Results: Central administration of Y5antisense ODNs significantly decreased body weight, and average adipocyte area. DNA fragmentationwas present after electrophoresis at epididymal adipose tissue. The expression of Bcl-2 gene wasdownregulated, while the expression of Bax upregulated. Conclusion: Lipolysis and adipocyteapoptosis may be important mechanisms far 75 antisense therapy.
文摘Objective: To study the efficacy of antisense oligonucleotide of neuropeptide Y (NPY) Y5 receptor on treating hyperleptinemia by intracerebral ventricular administration in diet-induced obese rats.Methods: The obese rats were prepared by feeding a high-nutritive diet for 7 weeks. The lateral ventricle of obese rats was cannulated. Either 10 μl of different neuropeptide Y Y5 receptor oligodeoxynucleotide, including antisense, sense and missense oligodeoxynucleotide (5 g/L) or 10 μl saline was administered into the ventricle through cannula three times per day in every rat. Two days later the rats were slaughtered .The weights of both retroperitoneal and epididymal adipose tissues were measured, and the serum insulin and leptin were detected by radioimmunoassay method and the murine leptin ELISA kit respectively. Results: ①The level of serum was significantly higher in experimental rats than that in normal rats. Similarly, the level of serum insulin and the weights of both retroperitoneal and epididymal adipose tissues were increased in experimental rats. ②After the diet-induced obese rats were intraventricularly administered with NPY Y5 receptor antisense oligodeoxynucleotide, the levels of serum leptin and insulin were significantly decreased and combined with the reduction of weight in retroperitoneal adipose tissue. There was, however, no significant difference in the weight of epidymal adipose tissue between pre-treated and post-treated duration. ③There was significant positive correlation among the level of serum leptin, the level of serum insulin and the weight of retroperritoneal adipose tissue in diet-induced obese rats. Conclusion: Intracerebral ventricular administration of antisense oligodeoxynucleotide of neuropeptide Y Y5 receptor may alleviate hyperleptinemia in diet-induced obese rats and decrease the weight of retroperitoneal adipose tissue and the level of serum insulin.
基金supported by the National Natural Science Foundation of China,No.30672578,81072756and81202644China National Funds for Distinguished Young Scientists,No.30825046+2 种基金Program for Innovative Research Team in Beijing University of Chinese Medicine,No.2011CXTD-07Program for University Key Teacher of Hebei Medical UniversitySpecialized Research Fund for the Doctoral Program of Higher Education,No.20121323120016
文摘In this study, Sprague-Dawley rats were immobilized to a frame for 3 hours a day for 21 days to establish a model of chronic immobilization stress. The body weight and food intake of rats subjected to chronic immobilization stress were significantly decreased compared with the control group. Dual-labeling immunofluorescence revealed that the expression of leptin receptor and the co-localization coeffient in these leptic receptor neurons in the arcuate nucleus of the hypothalamus were both upregulated, while the number of neuropeptide Y neurons was decreased. Chronic immobilization stress induced high expression of leptin receptor in the arcuate nucleus and suppressed the synthesis and secretion of neuropeptide Y, thereby disrupting the pathways in the arcuate nucleus that regulate feeding behavior, resulting in diminished food intake and reduced body weight.
文摘Objective: To study the role of β3-adrenergic receptor gene in neuropeptide Y(NPY) Y5 receptor antisense gene therapy of diet-induced obese rats.Methods: The diet-induced obese rats were prepared by feeding a high-nutrition diet. Lateral ventricular was cannulated in obese rats which then received an intraventricular injection of either 5 μg/μl NPY Y5 receptor antisense or 10 μl missense oligodeoxynucleotide or saline of 10 μl respectively in every rat. When the rats were killed, the wet weight of abdominal adipose tissue, the level of serum lipid and lipoprotein were measured. Total RNA from the retroperitoneal adipose tissue was extracted and the level of β3-adrenergic receptor gene mRNA expression was evaluated by RT-PCR.Results: ①The wet weight of abdominal adipose tissue, the levels of serum lipids were greatly higher in diet-induced obese rats than those in normal rats. However, there were much lower β3-adrenergic receptor gene mRNA expression levels in retroperitoneal adipose tissue in diet-induced obese rats as compared with those in normal rats. ②After the diet-induced obese rats were intraventricularly administered with NPY Y5 receptor antisense oligodeoxynucleotide, the levels of β3-adrenergic receptor gene mRNA expression in retroperitoneal adipose tissue of diet-induced obese rats were strikingly up-regulated, whereas the wet weight of abdominal adipose tissue, the levels of serum lipids were markedly reduced.Conclusion: Intraventricular administration of antisense oligodeoxynucleotide to NPY Y5 receptor could significantly reduce the abdominal adipose tissue and the levels of serum lipids in diet-induced obese rats by up-regulating the level of β3-adrenergic receptor gene mRNA expression in retroperitoneal adipose tissue.
基金Supported by Grant-in-Aid for Scientific Research (B) (18390065, 20390061) that on Priority Areas (15081101) from Japan Society for the Promotion of Science (JSPS)+2 种基金a grant from the 21st century Center of Excellence (COE) program, an Insulin Research Award from Novo Nordisk Pharma Ltd.a grant from Japan Diabetes Foundationa grant from the Smoking Research Foundation to TY
文摘AIM: To explore the mechanism for interactions of leptin with ghrelin and orexin in the arcuate nucleus (ARC) activating neuropeptide Y (NPY) neurons during physiological regulation of feeding, METHODS: Single neurons from ARC of adult rats with matured feeding function were isolated. [Ca2+]i was measured to monitore their activities. The time course of leptin effects on ghrelin-induced versus orexin-induced [Ca2+]i increases in NPY neurons was studied. RESULTS: Administration of ghrelin or orexin-A at 101~ mol/L increased cytosolic Ca2~ concentration ([Ca2+]~) in NPY neurons isolated from the ARC of adult rats. Upon administration of leptin at 10^-14-10^-12 mol/L, ghrelin-induced [Ca2+]i increases were initially (〈 10 min) inhibited but later restored, exhibiting a transient pattern of inhibition. In contrast, orexin-induced [Ca2+]i increases were inhibited by leptin in a long- lasting manner. Furthermore, a prior administration of leptin inhibited orexin action but not ghrelin action to increase ICa 2+li, CONCLUSION: Leptin counteracted ghrelin effects transiently and orexin effects long-lastingly in NPY neurons. The transient property with which leptin counteracts ghrelin action in NPY neurons may allow the fasting-associated increase in ghrelin levels to activate NPY neurons in the presence of physiological leptin and to stimulate feeding.
文摘BACKGROUND: It is known that acupuncture therapy can decrease plasma neuropeptide Y (NPY) levels in patients with cerebral infarction, but different types of acupuncture therapy used in various stages of cerebral infarction have not been evaluated. OBJECTIVE: To explore the effect of acupuncture therapy on resuscitation (Xingnao Kaiqiao) and plasma NPY levels in patients with very early stage acute cerebral infarction. DESIGN, TIME AND SETTING: This case-controlled study was performed at the Affiliated Hospital of the Medical College of the Chinese People's Armed Police Force between September 2004 and October 2005. PARTICIPANTS: Sixty patients with acute cerebral infarction of ≤ 6 hours were used in this study. Patients were randomly divided into an acupuncture therapy group (n = 30) and a routine treatment group (n = 30). Another 30 healthy subjects were used as the control group. METHODS: The acupuncture therapy of Xingnao Kaiqiao used in the acupuncture therapy group was based on routine western medical treatment and was performed at bilateral Neiguan (PCG) using the twirling, reinforcing-reducing method, Renzhong (DU26) using heavy bird-pecking needling, Sanyinjiao (SPG) using reinforcing and reducing by lifting and thrusting the needle, Jiquan (HT1), Weizhong (BL40) and Chize (LU5) using reinforcing and reducing by lifting and thrusting the needle. The acupuncture lasted for 14 days. Patients in the routine treatment group underwent routine medical treatment and no intervention was given to subjects in the control group. MAIN OUTCOME MEASURES: A 4 mL venous blood sample was obtained at different time points, i.e., immediately after hospitalization, the next morning, 7 and 14 days after treatment, to measure plasma NPY levels pre- and post-treatment using the radio-immunity method. RESULTS: The plasma NPY levels were significantly higher in both the routine treatment group and the acupuncture therapy group than in the control group pre- and post-treatment (P 〈 0.01). In particular, the plasma NPY levels in both the acupuncture therapy group and the routine treatment group were increased 7 days post-treatment but decreased from 7-14 days post-treatment. In addition, the plasma NPY levels were significantly lower in the acupuncture therapy group than in the routine treatment group on day 7 and 14 post-treatment (P 〈 0.01). CONCLUSION: Acupuncture therapy of Xingnao Kaiqiao can decrease plasma NPY levels in patients with very early stage acute cerebral infarction. In addition, the therapeutic effect of acupuncture with a prolonged therapy time is superior to routine treatment.
基金Science and Technology Research Projects of Heilongjiang Provincial Education Department, No. 11521276
文摘BACKGROUND: Previous research has revealed that somatostatin can induce epilepsy, and that the levels of neuropeptide Y may increase and become more active in brain areas with epileptic seizures. OBJECTIVE: To observe the effect of Ganoderma luciclum spore powder on the neuropeptide Y and somatostatin content in the cerebral cortex and hippocampal regions of seizure rats induced by pentylenetetrazol (PTZ). Furthermore, to verify any effect of Ganoderma lucidum spore powder on inhibition of epileptic seizures. DESIGN, TIME AND SETTING: A randomized group animal study was performed in August 2007 in the School of Basic Medical Sciences, Jiamusi University (Jiamusi, Heilongjiang, China). MATERIALS: Thirty healthy, male, Wistar rats, aged 12 weeks and weighing 180-220 g, were taken as the experimental animals. PTZ (Sigma Company, United States) was used to induce epilepsy. Ganoderma lucidum spores (Leyss, ex Fr variety) were purchased from Jiamusi City Wild Growing Case of the Ganoderma Lucidum (China). Rabbit anti-somatostatin antibodies and secondary antibodies were purchased from Wuhan Boster Company (China). Neuropeptide Y radioimmunoassay kit was purchased from Beijing Furui Biotechnology Company (China). METHODS: Thirty rats were randomly divided into three groups: a control group, an epilepsy model group and a Ganoderma lucidum spore-treated group. Each group contained 10 animals. Rats in the epilepsy model group were treated with intraperitoneal injections of PTZ and gastric perfusion of physiologic saline. In the Ganoderma lucidum spore-treated group, intraperitoneal injection of PTZ and gastric perfusion of Ganoderma lucidum spore powder were administered. The blank control group was only administered with the physiological saline by intraperitoneal injection and gastric perfusion. MAIN OUTCOME MEASURES: Immunohistochemical staining and radioimmunoassay methods were used to observe the changes of somatostatin and neuropeptide Y content in brain tissue of epileptic rats, as well as the morphology of neurons. RESULTS: All 30 rats were involved in the result analysis, without any loss. The number of somatostatin immunoreacted positive cells in the cerebral cortex and hippocampus was significantly increased in the epilepsy model group compared to the blank control group (P 〈 0.01). The number of somatostatin immunoreacted positive cells in cerebral cortex and hippocampus was significantly decreased in the Ganoderma lucidum spore-treated group compared to the epilepsy model group (P 〈 0.01). The contents of neuropeptide Y in cerebral cortex and hippocampus were significantly increased in the epilepsy model group compared to the blank control group (P 〈 0.01). The contents of neuropeptide Y in the cerebral cortex and hippocampus were significantly decreased in the Ganoderma lucidum spore-treated group compared to the epilepsy model group (P 〈 0.05). The epilepsy seizures in the Ganoderma lucidum spore-treated group were obviously reduced compared to the epilepsy model group. CONCLUSION: Ganoderma lucidum spore powder was able to reduce the somatostatin and neuropeptide Y content in the cerebral cortex and hippocampus effectively, so as to achieve an anti-epileptic function and protect neurons from being damaged.
基金Project supported by the Natural Science Foundation of ZhejiangProvince (No. Y306220)the Scientific Research Startup Fund ofZhejiang Academy of Agricultural Sciences, China
文摘Neuropeptide Y (NPY) is one of the most important orexigenic agents in central regulation of feeding behavior, body weight and energy homeostasis in domestic chickens. To examine differences in the hypothalamic NPY between layer-type and meat-type of chickens, which are two divergent kinds of the domestic chickens in feeding behavior and body weight, we detected mRNA levels of NPY in hypothalamic infundibular nucleus (IN), paraventricular nucleus (PVN) and lateral hypothalamic area (LHA) of these two types of chickens using one-step real time RT-PCR. The meat-type chicken had more food daily (about 1.7 folds) and greater body weights (about 1.5 folds) and brain weights than the layer-type chicken at the age of 14 d. In the meat-type of chicken, NPY mRNA levels of the IN and PVN were significantly greater than those of the LHA, and were not significantly different between the lN and PVN. However, in the layer-type of chicken, NPY mRNA levels were significantly greater in the IN than those in the LHA and PVN, and were not significantly different between the PVN and LHA. In all these hypothalamic regions the layer-type of chicken had significantly higher NPY mRNA levels than the meat-type chicken did. These results suggest the expression of NPY in the hypothalamus has a type-dependent pattern in domestic chickens.
文摘Neuropeptide Y gene transfection into normal rat brain tissue can provide gene overexpression, which can attenuate the severity of kainic acid-induced seizures. In this study, a recombinant adeno-associated virus carrying the neuropeptide Y gene was transfected into brain tissue of rats with kainic acid-induced epilepsy through stereotactic methods. Following these transfections, we verified overexpression of the neuropeptide Y gene in the epileptic brain. Electroencephalograms showed that seizure severity was significantly inhibited and seizure latency was significantly prolonged up to 4 weeks after gene transfection. Moreover, quantitative fluorescent PCR and western blot assays revealed that the mRNA and protein expression of the N-methyI-D-aspartate receptor subunits NR1, NR2A, and NR2B was inhibited in the hippocampus of epileptic rats. These findings indicate that neuropeptide Y may inhibit seizures via down-regulation of the functional expression of N-methyI-D-aspartate receptors.
文摘Exogenous neuropeptide Y has antiepileptic effects; however, the underlying mechanism and optimal administration method for neuropeptide Y are still unresolved. Previous studies have used intracerebroventricular injection of neuropeptide Y into animal models of epilepsy. In this study, a recombinant adeno-associated virus expression vector carrying the neuropeptide Y gene was injected into the lateral ventricle of rats, while the ipsilateral hippocampus was injected with kainic acid to establish the epileptic model. After transfection of neuropeptide Y gene, mossy fiber sprouting in the hippocampal CA3 region of epileptic rats was significantly suppressed, hippocampal synaptophysin (p38) mRNA and protein expression were inhibited, and epileptic seizures were reduced. These experimental findings indicate that a recombinant adeno-associated virus expression vector carrying the neuropeptide Y gene reduces mossy fiber sprouting and inhibits abnormal synaptophysin expression, thereby suppressing post-epileptic synaptic reconstruction.
基金supported by grants from the National Natural Science Foundation of China,No.31171019 and No.31200820the Opening Project of Shanghai Key Laboratory of Brain Functional Genomics and Key Laboratory of Brain Functional Genomics(East China Normal University)of the Ministry of Education
文摘Metformin may reduce food intake and body weight, but the anorexigenic effects of metformin are still poorly understood. In this study, Sprague-Dawley rats were administered a single intracere- broventricular dose of metformin and compound C, in a broader attempt to investigate the regula- tory effects of metformin on food intake and to explore the possible mechanism. Results showed that central administration of metformin significantly reduced food intake and body weight gain, par- ticularly after 4 hours. A reduction of neuropeptide Y expression and induction of AMP-activated protein kinase phosphorylation in the hypothalamus were also observed 4 hours after metformin administration, which could be reversed by compound C, a commonly-used antagonist of AMP-activated protein kinase. Furthermore, metformin also improved lipid metabolism by reducing plasma low-density lipoprotein. Our findings suggest that under normal physiological conditions, central regulation of appetite by metformin is related to a decrease in neuropeptide Y gene expres- sion, and that the activation of AMP-activated protein kinase may simply be a response to the anorexigenic effect of metformin.
基金This study was supported by the National Nature Science Foundation of China (No.30471772).
文摘OBJECTIVE Neuropeptide Y (NPY) acts as a neuroendocrine modulator in the anterior pituitary, and NPY mRNA and NPY-immunoreactivity have been detected in normal human anterior pituitaries. However, only a few studies of NPY expression in human pituitary adenomas have been published. Our study was conducted to determine whether or not adenomatous cells express NPY, to investigate the relationship between NPY expression and the subtypes of pituitary adenoma and to explore the clinical significance of NPY. METHODS The study included tissues from 58 patients with pituitary adenomas who underwent surgery because of their clinical diagnosis. Using a highly specific anti-NPY polyclonal antibody, immunohistochemical analysis was performed on the surgically removed pituitary adenomas. Six fresh specimens also were examined using immuno-electron microscopy. NPY was labeled with colloidal gold in order to study the distribution of NPY at the subcellular level. RESULTS The NPY expression level was significantly different among subgroups of pituitary adenomas (P〈0.05). NPY was immuno-detected in 58.6% of all adenomas, in 91.7% of gonadotrophic adenomas and in 14.3% of prolactinomas. NPY expression was slightly lower in invasive pituitary adenomas compared to noninvasive adenomas, but the difference was not significant (t=1.81, P〉0.05). Of particular interest was the finding that vascular endothelial cells showed positive NPY expression in some pituitary adenomas. Parts of strongly positive tumor cells were seen in channels formed without endothelial cells, but which contained some red blood cells in a formation similar to so-called vasculogenic mimicry. Immuno-electron microscopy demonstrated that 4 of the 6 fresh specimens displayed positive NPY staining with a high density of gold particles located mainly in the secretory granulas. In addition, gold particles were sparsely detected in the rough endoplasmic reticulum and cell matrix. CONCLUSION NPY exists in pituitary adenomas and its expression level was related to the types and biological characteristics of the pituitary adenomas. NPY may have a depressive effect on tumor cellular proliferation in pituitary adenomas. NPY possibly participates in modulating angiogenesis and hemodynamic changes in pituitary adenomas.
文摘Neuropeptide Y has been shown to inhibit the immunological activity of reactive microglia in the rat cerebral cortex, to reduce N-methyl-D-aspartate current(INMDA) in cortical neurons, and protect neurons. In this study, after primary cultured microglia from the cerebral cortex of rats were treated with lipopolysaccharide, interleukin-1β and tumor necrosis factor-α levels in the cell culture medium increased, and mRNA expression of these cytokines also increased. After primary cultured cortical neurons were incubated with the lipopolysaccharide-treated microglial conditioned medium, peak INMDA in neurons increased. These effects of lipopolysaccharide were suppressed by neuropeptide Y. After addition of the neuropeptide Y Y1 receptor antagonist BIBP3226, the effects of neuropeptide Y completely disappeared. These results suggest that neuropeptide Y prevents excessive production of interleukin-1β and tumor necrosis factor-α by inhibiting microglial reactivity. This reduces INMDA in rat cortical neurons, preventing excitotoxicity, thereby protecting neurons.
基金the Natural Science Research Project from Bureau of Public Health of Sichuan Province,No. 090194the Natural Science Research Project of Science Technology Bureau of Luzhou,No. 090102
文摘Our preliminary study demonstrated that neuropeptide Y (NPY)/nestin-positive cells exhibit a consistent spatial distribution in the hippocampus of normal adult rats. However, following severe acute and chronic stress-induced impaired learning and memory, synchronous decreased expression of nestin and NPY takes place in the hippocampus, and the underlying mechanisms remain unclear. In the present study, acute and chronic stress rat models were established using combined restrained and inverted stress. Results showed that learning and memory significantly decreased in acute and chronic stress rats. In addition, hippocampal cells were damaged, in particular in the acute stress rats, and nestin and NPY expression, as well as the number of NPY/nestin-positive cells in the CA3 region, significantly decreased. Furthermore, mature neurofilament 200-positive neurons were absent in the chronic stress rats. The NPY and cytoskeletal protein system equally contributed to stress-induced early learning and memory deficits as well as sustained cerebral iniurv in the adult hippocampus.
基金Supported by the National Natural Science Foundation of China,No.81830079Guangzhou Health Science and Technology Project,No.20191A011116Science and Technology Project of Guangzhou Huadu District,No.18-HDWS-003.
文摘Musculoskeletal disorders are the leading causes of disability and result in reduced quality of life.The neuro-osteogenic network is one of the most promising fields in orthopaedic research.Neuropeptide Y(NPY)system has been reported to be involved in the regulations of bone metabolism and homeostasis,which also provide feedback to the central NPY system via NPY receptors.Currently,potential roles of peripheral NPY in bone metabolism remain unclear.Growing evidence suggests that NPY can regulate biological actions of bone marrow mesenchymal stem cells,hematopoietic stem cells,endothelial cells,and chondrocytes via a local autocrine or paracrine manner by different NPY receptors.The regulative activities of NPY may be achieved through the plasticity of NPY receptors,and interactions among the targeted cells as well.In general,NPY can influence proliferation,apoptosis,differentiation,migration,mobilization,and cytokine secretion of different types of cells,and play crucial roles in the development of bone delayed/non-union,osteoporosis,and osteoarthritis.Further basic research should clarify detailed mechanisms of action of NPY on stem cells,and clinical investigations are also necessary to comprehensively evaluate potential applications of NPY and its receptor-targeted drugs in management of musculoskeletal disorders.
基金Supported by the National High Technology Research and Development Program of China(863 Program)(Nos.2012AA10A408,2012AA092203)the National Natural Science Foundation of China(No.31128017)the National Key Basic Program of Science and Technology-Platforms of Aquaculture Stock Resources(No.2006DKA30470017)
文摘Neuropeptide Y(NPY) is a 36-amino acid peptide of the neuropeptide Y family that plays key roles in the regulation of food intake. In this study,we focused on NPY m RNA expression changes around feeding time and during food deprivation in olive flounder. The olive flounder NPY m RNA levels were analyzed in different tissues and a high level of expression was detected in the brain. We also demonstrated a correlation between NPY expression levels in the brain and feeding schedule. NPY expression levels in olive flounder maintained on a daily scheduled feeding regimen increased shortly before feeding and decreased after the scheduled feeding time. Compared with the-1 h group before feeding,NPY expression in the 3 h group after feeding decreased significantly( P <0.05). Food deprivation led to an 81.7% decrease in NPY m RNA levels in the 24 h fasted group(P <0.05) and a 91.7% decrease in the 48 h fasted group(P <0.05). Therefore,our study demonstrates that NPY expression is associated with food intake in olive flounder. This result reveals the function of NPY in regulating food intake and its potential importance in olive flounder aquaculture.
文摘Neuropeptide Y (NPY) is a potent neurotransmitter for feeding. Besides NPY, orexigenic neuropeptides such as agouti-related protein (AgRP), and anorexi- genic neuropeptides such as α-melatonin stimulating hormone (MSH) and cocaine-amphetamine-regulated transcript (CART) are also involved in central feeding regulation. During fasting, NPY and AgRP gene expressions are up-regulated and POMC and CART gene ex- pressions are down-regulated in hypothalamus. Based on the network of peptidergic neurons, the former are involved in positive feeding regulation, and the latter are involved in negative feeding, which exert these feeding-regulated peptides especially in paraventricular nucleus (PVN). To clarify the compensatory mecha- nism of knock-out of NPY system on feeding, change in gene expressions of appetite-related neuropeptides and the feeding behavior was studied in NPY Y5-KO mice. Food intake was increased in Y5-KO mice. Fasting increased the amounts of food and water intake in the KO mice more profoundly. These data indicated the compensatory phenomenon of feeding behavior in Y5-KO mice. RT-PCR and ISH suggested that the compensation of feeding is due to change in gene expressions of AgRP, CART and POMC in hypothalamus. Thus, these fi ndings indicated that the compensatory mechanism involves change in POMC/CART gene expression in arcuate nucleus (ARC). The POMC/CART gene expression is important for central compensatory regulation in feeding behavior.
文摘BACKGROUND: Neuropeptide Y (NPY) may influence differentiation of Th cells immunological pathology of experimental allergic encephalomyelitis (EAE) is differentiation of Th cells It is assumed that the related to abnormal OBJECTIVE: To investigate the effect of NPY on white matter demyelination, the serum levels interleukin-4 (IL-4) and gamma-interferon (IFN-γ ), as well as EAE pathogenesis in an EAE guinea pig model following NPY injection into the lateral cerebral ventricle. DESIGN, TIME AND SETTING: A randomized controlled animal study, which was performed in the Infection Immunity Animal Laboratory, Affiliated Hospital of Luzhou Medical College, China, from October 2005 to April 2006. MATERIALS: Thirty healthy female guinea pigs of 8-12 weeks of age, and 10 healthy female rats of three months of age were used. NPY was provided by Sigma Company, USA. NPY kit was provided by Beijing Huaying Biotechnology Institute, China. METHODS: Thirty guinea pigs were randomly divided into three groups: normal control group, EAE model group, and NPY intervention group (n =10 per group). Normal control group and EAE model group: Saline (10μ L, once) was injected into the lateral cerebral ventricle. After one week, the same volume of Freund's adjuvant complete was either injected subcutaneously into two post-palms or EAE was modeled. NPY intervention group: EAE was modeled after one week and NPY was injected (10 μ L of 6 nmol NPY, once) into the lateral cerebral ventricle. Myelin basic protein (MBP) antigen made from rat spinal cord homogenate and Freund's adjuvant complete were injected subcutaneously into both post-palms (0.2 mL per palm) to establish the EAE model. MAIN OUTCOME MEASURES: White matter demyelination of the cerebrum, cerebellum, brain stem, and spinal cord were observed by light microscopy after HE staining. Levels of serum IFN-γ and IL-4 were detected by the double antibody sandwich ABC-ELISA technique. NPY content was detected by radioimmunoassay. RESULTS: Pathological alterations in the NPY intervention groups were reduced compared to those in the EAE model group, suggesting a reduction and remission of white matter demyelination with NPY treatment. When compared to the model group, the serum IL-4 level was increased in the NPY intervention group during the high-frequent EAE stage (P 〈 0.01), but the serum IFN-γ level was decreased (P 〈 0.01). Furthermore, the EAE latency was prolonged (P 〈 0.01), the neurological scores were decreased in the high-frequent EAE stage (P 〈 0.01), and the death rate was decreased (P 〈 0.05). NPY content and the serum IL-4 level at the peak stage were positively correlated with those in the latent phase (r =0.863-0.900, P 〈 0.01), but negatively correlated with neurological scores at the peak stage (r=- -0.068 to -0.863, P 〈 0.05-0.01). The IFN-γ level at the peak stage was negatively correlated to that in the latent phase (r = -0.683-0.650, P 〈 0.05), but positively correlated to neurological scores at the peak stage (r =0.975, 0.845, P 〈 0.05). CONCLUSION: NPY injection into the lateral cerebral ventricle can promote the secretion of IL-4, inhibit the production of IFN-γ, relieve white matter demyelination, and inhibit EAE attack in an experimental model of EAE.
基金supported by a grant from the National Natural Science Foundation of China(No.81172898)
文摘Death following situations of intense emotional stress has been linked to the cardiac pathology described as stress cardiomyopathy, whose pathomechanism is still not clear. In this study, we sought to determine, via an animal model, whether the transcriptional coactivator peroxisome proliferator-activated receptor γ coactivator-1alpha (PGC-1α) and the amino peptide neuropeptide Y (NPY) play a role in the pathogenesis of this cardiac entity. Male Sprague-Dawley rats in the experimental group were subjected to immobilization in a plexy glass box for 1 h, which was followed by low voltage elec-tric foot shock for about 1h at 10s intervals in a cage fitted with metallic rods. After 25 days the rats were sacrificed and sections of their hearts were processed. Hematoxylin-eosin staining of cardiac tissues revealed the characteristic cardiac lesions of stress cardiomyopathy such as contraction band necrosis, inflammatory cell infiltration and fibrosis. The semi-quantitative RT-PCR analysis for PGC-1α mRNA expression showed significant overexpression of PGC1-α in the stress-subjected rats (P<0.05). Fluorescence immunohistochemistry revealed a higher production of NPY in the stress-subjected rats as compared to the control rats (P=0.0027). Thus, we are led to conclude that following periods of intense stress, an increased expression of PGC1-α in the heart and an overflow of NPY may lead to stress car-diomyopathy and even death in susceptible victims. Moreover, these markers can be used to identify stress cardiomyopathy as the cause of sudden death in specific cases.