BACKGROUND Serotonin receptor 2B(5-HT2B receptor)plays a critical role in many chronic pain conditions.The possible involvement of the 5-HT2B receptor in the altered gut sensation of irritable bowel syndrome with diar...BACKGROUND Serotonin receptor 2B(5-HT2B receptor)plays a critical role in many chronic pain conditions.The possible involvement of the 5-HT2B receptor in the altered gut sensation of irritable bowel syndrome with diarrhea(IBS-D)was investigated in the present study.AIM To investigate the possible involvement of 5-HT2B receptor in the altered gut sensation in rat model and patients with IBS-D.METHODS Rectosigmoid biopsies were collected from 18 patients with IBS-D and 10 patients with irritable bowel syndrome with constipation who fulfilled the Rome IV criteria and 15 healthy controls.The expression level of the 5-HT2B receptor in colon tissue was measured using an enzyme-linked immunosorbent assay and correlated with abdominal pain scores.The IBS-D rat model was induced by intracolonic instillation of acetic acid and wrap restraint.Alterations in visceral sensitivity and 5-HT2B receptor and transient receptor potential vanilloid type 1(TRPV1)expression were examined following 5-HT2B receptor antagonist adminis-tration.Changes in visceral sensitivity after administration of the TRPV1 antago-INTRODUCTION Irritable bowel syndrome(IBS)is a chronic functional bowel disorder characterized by recurrent abdominal pain with altered bowel habits that affects approximately 15%of the population worldwide[1].IBS significantly impacts the quality of life of patients.Although the pathogenesis of IBS is not completely understood,the role of abnormal visceral sensitivity in IBS has recently emerged[2,3].5-Hydroxytryptamine(5-HT)is known to play a key role in the physiological states of the gastrointestinal tract.Plasma 5-HT levels in IBS with diarrhea(IBS-D)patients were greater than those in healthy controls[4],suggesting a possible role of 5-HT in the pathogenesis of IBS-D.The serotonin receptor 2(5-HT2 receptor)family comprises three subtypes:5-HT2A,5-HT2B,and 5-HT2c.All 5-HT2 receptors exhibit 46%-50%overall sequence identity,and all of these receptors preferentially bind to Gq/11 to increase inositol phosphates and intracellular calcium mobilization[5].5-HT2B receptors are widely expressed throughout the gut,and experimental evidence suggests that the primary function of 5-HT2B receptors is to mediate contractile responses to 5-HT through its action on smooth muscle[6].The 5-HT2B receptor is localized to both neurons of the myenteric nerve plexus and smooth muscle in the human colon.The 5-HT2B receptor mediates 5-HT-evoked contraction of longitudinal smooth muscle[6].These findings suggest that the 5-HT2B receptor could play an important role in modulating colonic motility,which could affect sensory signaling in the gut.Other laboratories have shown that the 5-HT2B receptor participates in the development of mechanical and formalin-induced hyperalgesia[7,8].A 5-HT2B receptor antagonist reduced 2,4,6-trinitrobenzene sulfonic acid(TNBS)and stress-induced visceral hyperalgesia in rats[9,10].However,the role of the 5-HT2B receptor in IBS-D patients and in acetic acid-and wrap restraint-induced IBS-D rat models was not investigated.展开更多
Background Serotonin is an important signaling molecule that regulates secretory and sensory functions in the gut.Gut microbiota has been demonstrated to affect serotonin synthesis in rodent models.However,how gut mic...Background Serotonin is an important signaling molecule that regulates secretory and sensory functions in the gut.Gut microbiota has been demonstrated to affect serotonin synthesis in rodent models.However,how gut microbes regulate intestinal serotonin production in piglets remains vague.To investigate the relationship between microbiota and serotonin specifically in the colon,microbial composition and serotonin concentration were analyzed in ileum-cannulated piglets subjected to antibiotic infusion from the ileum when comparing with saline infusion.Microbes that correlated positively with serotonin production were isolated from piglet colon and were further used to investi-gate the regulation mechanisms on serotonin production in IPEC-J2 and a putative enterochromaffin cell line RIN-14B cells.Results Antibiotic infusion increased quantities of Lactobacillus amylovorus(LA)that positively correlated with increased serotonin concentrations in the colon,while no effects observed for Limosilactobacillus reuteri(LR).To understand how microbes regulate serotonin,representative strains of LA,LR,and Streptococcus alactolyticus(SA,enriched in feces from prior observation)were selected for cell culture studies.Compared to the control group,LA,LR and SA supernatants significantly up-regulated tryptophan hydroxylase 1(TPH1)expression and promoted serotonin production in IPEC-J2 cells,while in RIN-14B cells only LA exerted similar action.To investigate potential mechanisms mediated by microbe-derived molecules,microbial metabolites including lactate,acetate,glutamine,andγ-aminobutyric acid were selected for cell treatment based on computational and metabolite profiling in bacte-rial supernatant.Among these metabolites,acetate upregulated the expression of free fatty acid receptor 3 and TPH1 while downregulated indoleamine 2,3-dioxygenase 1.Similar effects were also recapitulated when treating the cells with AR420626,an agonist targeting free fatty acid receptor 3.Conclusions Overall,these results suggest that Lactobacillus amylovorus showed a positive correlation with sero-tonin production in the pig gut and exhibited a remarkable ability to regulate serotonin production in cell cultures.These findings provide evidence that microbial metabolites mediate the dialogue between microbes and host,which reveals a potential approach using microbial manipulation to regulate intestinal serotonin biosynthesis.展开更多
In animals,serotonin is a neurotransmitter and mood regulator.In plants,serotonin functions in energy acquisition,tissue maintenance,delay of senescence,and response to biotic and abiotic stresses.In this study,we exa...In animals,serotonin is a neurotransmitter and mood regulator.In plants,serotonin functions in energy acquisition,tissue maintenance,delay of senescence,and response to biotic and abiotic stresses.In this study,we examined the effect of serotonin enrichment of rice endosperm on plant growth,endosperm development,and grain quality.To do so,TDCs and T5H were selected as targets for serotonin fortification.Overexpression of TDC1 or TDC3 increased serotonin accumulation relative to overexpression of T5H in rice grain.Transgenic lines of target genes driven by the Gt1 promoter showed better field performance than those driven by the Ubi promoter.Overexpression of T5H showed little effect on plant growth or grain physicochemical quality.In neuronal cell culture assays,serotonin induced neuroprotective action against apoptosis.Breeding of rice cultivars with high serotonin content may be beneficial for health and nutrition.展开更多
<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:""><span style="font-family:Verdana;"> It is not well analyze...<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:""><span style="font-family:Verdana;"> It is not well analyzed whether there are differences in plasma levels of tryptophan (TRP) metabolites between healthy control people (HC) and patients of major monopolar depression (MMD). </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> Ultra high-speed </span></span><span style="font-family:""><span style="font-family:Verdana;">liquid chromatography/mass spectrometry has been used for the simultaneous determination of plasma levels of tryptophan metabolites in depressive </span><span><span style="font-family:Verdana;">patients. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> There are no significant differences between plasma levels of TRP between HC and MMD. Plasma levels of TRP of HC are higher in young men, young women, old men, and old women in this order. Serotonin (5-HT) levels are higher in MMD than HC. Plasma levels of 5-HIAA of HC are also higher than those of patients of MMD. Plasma levels of kynurenine (KYN) of healthy old men and old women are higher than those of young men and old women. Plasma levels of KYN are higher in old women and young men of MMD than those of HC. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> Plasma levels of 5-HT are higher in patients of MMD than those of HC, which may suggest that use of drugs inhibiting the 5-HT transportation may increase plasma levels of 5-HT in MMD.展开更多
BACKGROUND Serotonin syndrome(SS)is an underdiagnosed drug-induced clinical syndrome resulting from the excess intrasynaptic concentration of serotonin.Very limited information is available about chronic SS.AIM To eva...BACKGROUND Serotonin syndrome(SS)is an underdiagnosed drug-induced clinical syndrome resulting from the excess intrasynaptic concentration of serotonin.Very limited information is available about chronic SS.AIM To evaluate the epidemiological,clinical,and other aspects of the insidious onset SS.METHODS We retrospectively evaluated 14 consecutive adult patients(>18 years)who had complaints for more than 6 wk at the time of consultation and met the Hunter criteria for SS.RESULTS The mean age was 41.1 years(range:21-61 years),with a male preponderance(64%).Although tremors were observed in all patients,this was a presenting complaint in only 43%of patients.Generalized body pain,insomnia,and restlessness were common presenting features(50%each).Other common clinical features were stiffness of the limbs(43%),diaphoresis(43%),gait disturbances(36%),bowel disturbances(36%),dizziness(29%),sexual dysfunctions(21%),incoordination(14%),and fatigue(14%)The mean duration of symptoms before the diagnosis of SS was 13.5±5.8 wk(range:6-24 wk).Amitriptyline was the most common drug(n=6,43%),followed by tramadol(n=5,36%)and sodium valproate(n=5,36%).All patients received cyproheptadine,a 5-hydroxytryptamine2A antagonist,as treatment and noted an excellent response CONCLUSION This study represents the largest study on chronic SS.We suggest that patients receiving serotonergic drugs should be physically examined for the presence of SS upon the development of new symptoms.展开更多
Serotonin(5-HT) and the serotonin transporter(SERT) have earned a tremendous amount of attention regarding the pathogenesis of irritable bowel syndrome(IBS). Considering that enteric 5-HT is responsible for the secret...Serotonin(5-HT) and the serotonin transporter(SERT) have earned a tremendous amount of attention regarding the pathogenesis of irritable bowel syndrome(IBS). Considering that enteric 5-HT is responsible for the secretion, motility and perception of the bowel, the involvement of altered enteric 5-HT metabolism in the pathogenesis of IBS has been elucidated. Higher 5-HT availability is commonly associated with depressed SERT mR NA in patients with IBS compared with healthy controls. The expression difference of SERT between IBS patients and healthy controls might suggest that SERT plays an essential role in IBS pathogenesis, and SERT was expected to be a novel therapeutic target for IBS. Progress in this area has begun to illuminate the complex regulatory mechanisms of SERT in the etiology of IBS. In this article, current insights regarding the regulation of SERT in IBS are provided, including aspects of SERT gene polymorphisms, microR NAs, immunity and inflammation, gut microbiota, growth factors, among others. Potential SERT-directed therapies for IBS are also described. The potential regulators of SERT are of clinical importance and are important for better understanding IBS pathophysiology and therapeutic strategies.展开更多
AIM:To determine the molecular mechanisms of Shugan decoction(SGD) in the regulation of colonic motility and visceral hyperalgesia(VHL) in irritable bowel syndrome(IBS).METHODS:The chemical compounds contained in SGD ...AIM:To determine the molecular mechanisms of Shugan decoction(SGD) in the regulation of colonic motility and visceral hyperalgesia(VHL) in irritable bowel syndrome(IBS).METHODS:The chemical compounds contained in SGD were measured by high-performance liquid chromatography.A rat model of IBS was induced by chronic water avoidance stress(WAS).The number of fecal pellets was counted after WAS and the pain pressure threshold was measured by colorectal distension.Morphological changes in colonic mucosa were detected by hematoxylin-eosin staining.The contents of tumor necrosis factor(TNF)-αin colonic tissue and calcitonin-gene-related peptide(CGRP)in serum were measured by ELISA.The protein expression of serotonin[5-hydroxytryptamide(5-HT)],serotonin transporter(SERT),chromogranin A(Cg A)and CGRP incolon tissue was measured by immunohistochemistry.RESULTS:SGD inhibited colonic motility dysfunction and VHL in rats with IBS.Blockers of transient receptor potential(TRP)vanilloid 1(TRPV1)(Ruthenium Red)and TRP ankyrin-1(TRPA1)(HC-030031)and activator of protease-activated receptor(PAR)4 increased the pain pressure threshold,whereas activators of PAR2and TRPV4 decreased the pain pressure threshold in rats with IBS.The effect of SGD on pain pressure threshold in these rats was abolished by activators of TRPV1(capsaicin),TRPV4(RN1747),TRPA1(Polygodial)and PAR2(AC55541).In addition,CGRP levels in serum and colonic tissue were both increased in these rats.TNF-αlevel in colonic tissue was also significantly upregulated.However,the levels of 5-HT,SERT and Cg A in colonic tissue were decreased.All these pathological changes in rats with IBS were attenuated by SGD.CONCLUSION:SGD alleviated VHL and attenuated colon motility in IBS,partly by regulating TRPV1,TRPV4,TRPA1,PAR2,5-HT,Cg A and SERT,and reducing CGRP and TNF-αlevel.展开更多
AIM To evaluate the effect of Lactobacillus rhamnosus GG supernatant(LGG-s) on the expression of serotonin transporter(SERT) in rats with post-infectious irritable bowel syndrome(PI-IBS).METHODS Campylobacter jejuni 8...AIM To evaluate the effect of Lactobacillus rhamnosus GG supernatant(LGG-s) on the expression of serotonin transporter(SERT) in rats with post-infectious irritable bowel syndrome(PI-IBS).METHODS Campylobacter jejuni 81-176(1010 CFU/m L) was used to induce intestinal infection to develop a PI-IBS model. After evaluation of the post-infectious phase by biochemical tests, Dn A agarose gel electrophoresis, abdominal withdrawal reflex(AWR) test, and the intestinal motility test, four PI-IBS groups received different concentrations of LGG-s for 4 wk. The treatments were maintained for 1.0, 2.0, 3.0 or 4.0 wk during the experiment, and the colons and brains were removed for later use each week. SERT m Rn A and protein levels were detected by real-time PCR and Western blot, respectively.RESULTS The levels of SERT m Rn A and protein in intestinal tissue were higher in rats treated with LGG-s than in control rats and PI-IBS rats gavaged with PBS during the whole study. Undiluted LGG-s up-regulated SERT m Rn A level by 2.67 times compared with the control group by week 2, and SERT m Rn A expression kept increasing later. Double-diluted LGG-s was similar to undiluted-LGG-s, resulting in high levels of SERT m Rn A. Triple-diluted LGG-s up-regulated SERT m Rn A expression level by 6.9-times compared with the control group, but SERT m Rn A expression decreased rapidly at the end of the second week. At the first week, SERT protein levels were basically comparable in rats treated with undiluted LGG-s, double-diluted LGG-s, and triplediluted LGG-s, which were higher than those in the control group and PBS-treated PI-IBS group. SERT protein levels in the intestine were also comparable in rats treated with undiluted LGG-s, double-diluted LGG-s, and triple-diluted LGG-s by the second and third weeks. SERT m Rn A and protein levels in the brain had no statistical difference in the groups during the experiment.CONCLUSION LGG-s can up-regulate SERT m Rn A and protein levels in intestinal tissue but has no influence in brain tissue in rats with PI-IBS.展开更多
Given the failure to develop disease-modifying therapies for Alzheimer’s disease(AD),strategies aiming at preventing or delaying the onset of the disease are being prioritized.While the debate regarding whether depre...Given the failure to develop disease-modifying therapies for Alzheimer’s disease(AD),strategies aiming at preventing or delaying the onset of the disease are being prioritized.While the debate regarding whether depression is an etiological risk factor or a prodrome of AD rages on,a key determining factor may be the timing of depression onset in older adults.There is increasing evidence that untreated early-onset depression is a risk factor and that late-onset depression may be a catalyst of cognitive decline.Data from animal studies have shown a beneficial impact of selective serotonin reuptake inhibitors on pathophysiological biomarkers of AD including amyloid burden,tau deposits and neurogenesis.In humans,studies focusing on subjects with a prior history of depression also showed a delay in the onset of AD in those treated with most selective serotonin reuptake inhibitors.Paroxetine,which has strong anticholinergic properties,was associated with increased mortality and mixed effects on amyloid and tau deposits in mice,as well as increased odds of developing AD in humans.Although most of the data regarding selective serotonin reuptake inhibitors is promising,findings should be interpreted cautiously because of notable methodological heterogeneity between studies.There is thus a need to conduct large scale randomized controlled trials with long follow up periods to clarify the dose-effect relationship of specific serotonergic antidepressants on AD prevention.展开更多
BACKGROUND Visceral hypersensitivity and psychological performance are the main pathophysiological mechanisms of irritable bowel syndrome(IBS).Previous studies have found that cholecystokinin(CCK)can enhance colon mov...BACKGROUND Visceral hypersensitivity and psychological performance are the main pathophysiological mechanisms of irritable bowel syndrome(IBS).Previous studies have found that cholecystokinin(CCK)can enhance colon movement and that serotonin transporter(SERT)is a transmembrane transport protein with high affinity for 5-hydroxytryptamine,which can rapidly reuptake 5-hydroxytryptamine and then regulate its action time and intensity.We speculate that SERT and CCK might play a role in the pathogenesis of diarrheapredominant IBS(IBS-D)by affecting visceral sensitivity and the brain-gut axis.AIM To determine SERT and CCK levels in IBS-D patients diagnosed using Rome IV criteria and to analyze their associations with abdominal pain,visceral hypersensitivity and psychological performance.METHODS This study collected data from 40 patients with IBS-D at the China-Japan Friendship Hospital from September 2017 to April 2018 and 18 healthy controls.The severity of abdominal pain,visceral sensitivity and psychological performance were evaluated in IBS-D patients and healthy controls,the levels of SERT and CCK in plasma and colonic mucosa were evaluated,and the correlations between them were analyzed.RESULTS There were significant differences in the initial sensation threshold(31.00±8.41 mL vs 52.22±8.09 mL,P<0.001),defecating sensation threshold(51.75±13.57 mL vs 89.44±8.73 mL,P<0.001)and maximum tolerable threshold(97.25±23.64 mL vs 171.11±20.83 mL,P<0.001)between the two groups.IBS-D patients had more severe anxiety(7.78±2.62 vs 2.89±1.02,P<0.001)and depressive(6.38±2.43 vs 2.06±0.73,P<0.001)symptoms than healthy controls.Significant differences were also found in mucosal CCK(2.29±0.30 vs 1.66±0.17,P<0.001)and SERT(1.90±0.51 vs 3.03±0.23,P<0.001)between the two groups.There was a significant positive correlation between pain scores and mucosal CCK(r=0.96,0.93,0.94,P<0.001).Significant negative correlations between anxiety(r=-0.98;P<0.001),depression(r=-0.99;P<0.001),pain evaluation(r=-0.96,-0.93,-0.95,P<0.001)and mucosal SERT were observed.CONCLUSION IBS-D patients had psychosomatic disorders and visceral hypersensitivity.SERT and CCK might be involved in the pathogenesis of IBS-D by regulating the braingut axis and affecting visceral sensitivity.This provides a new potential method for identifying a more specific and effective therapeutic target.展开更多
Previous studies suggest that serotonin(5-HT) might interact with brain-derived neurotrophic factor(BDNF) during the stress response.However,the relationship between 5-HT and BDNF expression under purely psychological...Previous studies suggest that serotonin(5-HT) might interact with brain-derived neurotrophic factor(BDNF) during the stress response.However,the relationship between 5-HT and BDNF expression under purely psychological stress is unclear.In this study,one hour before psychological stress exposure,the 5-HT1 A receptor agonist 8-OH-DPAT or antagonist MDL73005,or the 5-HT2 A receptor agonist DOI or antagonist ketanserin were administered to rats exposed to psychological stress.Immunohistochemistry and in situ hybridization revealed that after psychological stress,with the exception of the ventral tegmental area,BDNF protein and m RNA expression levels were higher in the 5-HT1 A and the 5-HT2 A receptor agonist groups compared with the solvent control no-stress or psychological stress group in the CA1 and CA3 of the hippocampus,prefrontal cortex,central amygdaloid nucleus,dorsomedial hypothalamic nucleus,dentate gyrus,shell of the nucleus accumbens and the midbrain periaqueductal gray.There was no significant difference between the two agonist groups.In contrast,after stress exposure,BDNF protein and m RNA expression levels were lower in the 5-HT1 A and 5-HT2 A receptor antagonist groups than in the solvent control non-stress group,with the exception of the ventral tegmental area.Our findings suggest that 5-HT regulates BDNF expression in a rat model of acute psychological stress.展开更多
The neuromodulatory transmitter serotonin(5-hydroxytryptamine,5-HT)is synthesized by neurons located in the brainstem,which project more or less densely to the entire central nervous system(Charnay and Leger,2010).Ser...The neuromodulatory transmitter serotonin(5-hydroxytryptamine,5-HT)is synthesized by neurons located in the brainstem,which project more or less densely to the entire central nervous system(Charnay and Leger,2010).Serotonin regulates a variety of physiological functions,including food intake,reward,reproduction,sleep-wake cycle,memory,cognition,emotion,and mood(Charnay and Leger,2010).展开更多
BACKGROUND:Liver disease is commonly seen in the clinic and its pathological characteristic is combined hepatocellular death and apoptosis.Promoting hepatocyte regeneration is one of the main methods of treating liver...BACKGROUND:Liver disease is commonly seen in the clinic and its pathological characteristic is combined hepatocellular death and apoptosis.Promoting hepatocyte regeneration is one of the main methods of treating liver disease.Serotonin(5-HT)is an important compound which participates in various life process,and 95%of it is carried by platelets in the blood.A recent finding showed that platelet-derived serotonin is the key factor in liver regeneration,which fails without serotonin.This study aimed to investigate the effects of quipazine,a selective 5-HT receptor agonist,on proliferation and apoptosis in the human hepatocyte strain L-02. METHODS:L-02 cells were cultured in medium with 5-HT and quipazine,and samples were collected at 24,48,and 72 hours.The methyl thiazolyl tetrazolium(MTT)method was used to test viability,flow cytometry to assess the cell cycle,the Annexin-V/PI method to evaluate apoptosis,and immunohistochemistry to detect proliferating cell nuclear antigen(PCNA). RESULTS:Compared with the control group,the viability of L-02 cells was improved in the 10,50,and 250μg/ml quipazine groups(P<0.05);the percentage of S-phase and PCNA-positive cells were increased in the 2,10,50,and 250μg/ml quipazine groups(P>0.05);and no difference in the percentage of apoptotic cells was found between the 50 μg/ml quipazine and control groups(P>0.05).CONCLUSION:Quipazine improves proliferation of a human hepatocyte strain in vitro,and this is not based on the inhibition of apoptosis.展开更多
Angiotensin II (Ang II) is a critical component of the reninangiotensin system that contributes to hypertension. Although platelets in blood from hypertensive subjects have an abnormal biological profile, it is unclea...Angiotensin II (Ang II) is a critical component of the reninangiotensin system that contributes to hypertension. Although platelets in blood from hypertensive subjects have an abnormal biological profile, it is unclear if circulating Ang II influences platelet aggregation or thrombus formation. One of the abnormalities presented to the platelets during hypertension is an elevated plasma concentration of serotonin (5-HT) caused by reduced 5-HT uptake secondary to loss of the 5-HT transporter (SERT) on the platelet plasma membrane. In the current study, we evaluated in vivo platelet function after 7 days of subcutaneous Ang II infusion to establish hypertension in mice and additionally assessed the biology of isolated platelets exposed to Ang II in vitro. The administration of Ang II elevated systolic blood pressure, but markers of platelet activation including P-selectin and PEJon/A staining were not changed. However, the aggregation response to collagen was reduced in isolated platelets from Ang II-infused mice, which also showed reduced 5-HT uptake by SERT. In vitro exposure of isolated platelets to Ang II also resulted in a loss of surface SERT associated with a reduced aggregation response to collagen. These abnormalities were reversed by increasing concentra tions of the Ang II receptor antagonist, valsartan. Interestingly, SERT KO mice failed to fully develop hypertension in response to Ang II infusion and isolated platelets from these animals were insensitive to the anti-aggregatory influence of Ang II. Thus, Ang II blunts the aggregation responses of platelets and the mechanism underlying this action may involve a loss of SERT on the platelet plasma membrane. The latter event depletes intracellular 5-HT in platelets, an event that is associated with reduced aggregation. The widespread use of antihypertensive drugs that target the renin-angiotensin system suggest the potential clinical utility of our findings and emphasize the importance of understanding the impact of Ang II on platelet function.展开更多
Previously, we reported that changes induced in autonomic neurotransmission in rats by Lactobacillus brevis SBC8803 may be mediated by serotonin 3 (5-HT3) receptors. In this study, we evaluated the effects of heat-kil...Previously, we reported that changes induced in autonomic neurotransmission in rats by Lactobacillus brevis SBC8803 may be mediated by serotonin 3 (5-HT3) receptors. In this study, we evaluated the effects of heat-killed L. brevis SBC8803 on serotonin (5-HT) releasing from intestinal cells. In the in vitro study, L. brevis SBC8803 stimulated 5-HT release from cultured rat endocrine RIN-14B cells (SBC8803 vs. sterile water;P in vivo study, 2 mg of heat-killed L. brevis SBC8803 was administered using a stomach sonde (feeding needle) to C57BL/6J mice. Analysis of plasma by ELISA showed gradually increase in 5-HT concentrations (0 min vs. 60 min;P ex vivo cultured intestinal loops composed of duodenum and part of the jejunum, from C3H/HeN and C57BL/6J male mice indicated that L. brevis SBC8803 effectively induced 5-HT release (SBC8803 vs. sterile water;P L. brevis SBC8803 may stimulate 5-HT release from mouse intestinal cells such as enterochromaffin cells.展开更多
BACKGROUND Bacillus subtilis(B.subtilis),Enterococcus faecium(E.faecium),and Enterococcus faecalis(E.faecalis)are probiotics that are widely used in the clinical treatment of irritable bowel syndrome(IBS).Whether the ...BACKGROUND Bacillus subtilis(B.subtilis),Enterococcus faecium(E.faecium),and Enterococcus faecalis(E.faecalis)are probiotics that are widely used in the clinical treatment of irritable bowel syndrome(IBS).Whether the supernatants of these three probiotics can improve gastrointestinal sensation and movement by regulating the serotonin transporter(SERT)expression needs to be clarified.AIM To investigate whether B.subtilis,E.faecium,and E.faecalis supernatants can upregulate SERT expression in vitro and in vivo.METHODS Caco-2 and HT-29 cells were stimulated with probiotic culture supernatants for 12 and 24 h,respectively.A male Sprague-Dawley rat model of post-infectious irritable bowel syndrome(PI-IBS)was established and the rats were treated with phosphate-buffered saline(group A)and three probiotics culture supernatants(groups B,C,and D)for 4 wk.The levels of SERT were detected by quantitative PCR and western blotting.RESULTS The levels of SERT at post-treatment 12 and 24 h were significantly elevated in Caco-2 cells treated with B.subtilis supernatant compared with those in the control group(aP<0.05).Those levels were markedly upregulated in Caco-2 cells stimulated with E.faecium and E.faecalis supernatants at 24 h(aP<0.05).In addition,SERT expression in groups B,C,and D was significantly higher than that in group A in the 2nd wk(aP<0.05).Increased SERT expression was only found in group D in the 3rd wk(aP<0.05).However,there was no significant difference in SERT expression between the groups in the last week(P>0.05).CONCLUSION The supernatants of B.subtilis,E.faecium,and E.faecalis can upregulate SERT expression in intestinal epithelial cells and the intestinal tissues in the rat model of PI-IBS.展开更多
基金The Health Commission of Jinshan District,Shanghai,China,No.JSKJ-KTMS-2019-01The Youth Research Foundation of Jinshan Hospital of Fudan University,No.JYQN-JC-202101 and No.JYQN-JC-202216The Reserve Discipline Construction of Jinshan Hospital of Fudan University,No.HBXK-2021-2.
文摘BACKGROUND Serotonin receptor 2B(5-HT2B receptor)plays a critical role in many chronic pain conditions.The possible involvement of the 5-HT2B receptor in the altered gut sensation of irritable bowel syndrome with diarrhea(IBS-D)was investigated in the present study.AIM To investigate the possible involvement of 5-HT2B receptor in the altered gut sensation in rat model and patients with IBS-D.METHODS Rectosigmoid biopsies were collected from 18 patients with IBS-D and 10 patients with irritable bowel syndrome with constipation who fulfilled the Rome IV criteria and 15 healthy controls.The expression level of the 5-HT2B receptor in colon tissue was measured using an enzyme-linked immunosorbent assay and correlated with abdominal pain scores.The IBS-D rat model was induced by intracolonic instillation of acetic acid and wrap restraint.Alterations in visceral sensitivity and 5-HT2B receptor and transient receptor potential vanilloid type 1(TRPV1)expression were examined following 5-HT2B receptor antagonist adminis-tration.Changes in visceral sensitivity after administration of the TRPV1 antago-INTRODUCTION Irritable bowel syndrome(IBS)is a chronic functional bowel disorder characterized by recurrent abdominal pain with altered bowel habits that affects approximately 15%of the population worldwide[1].IBS significantly impacts the quality of life of patients.Although the pathogenesis of IBS is not completely understood,the role of abnormal visceral sensitivity in IBS has recently emerged[2,3].5-Hydroxytryptamine(5-HT)is known to play a key role in the physiological states of the gastrointestinal tract.Plasma 5-HT levels in IBS with diarrhea(IBS-D)patients were greater than those in healthy controls[4],suggesting a possible role of 5-HT in the pathogenesis of IBS-D.The serotonin receptor 2(5-HT2 receptor)family comprises three subtypes:5-HT2A,5-HT2B,and 5-HT2c.All 5-HT2 receptors exhibit 46%-50%overall sequence identity,and all of these receptors preferentially bind to Gq/11 to increase inositol phosphates and intracellular calcium mobilization[5].5-HT2B receptors are widely expressed throughout the gut,and experimental evidence suggests that the primary function of 5-HT2B receptors is to mediate contractile responses to 5-HT through its action on smooth muscle[6].The 5-HT2B receptor is localized to both neurons of the myenteric nerve plexus and smooth muscle in the human colon.The 5-HT2B receptor mediates 5-HT-evoked contraction of longitudinal smooth muscle[6].These findings suggest that the 5-HT2B receptor could play an important role in modulating colonic motility,which could affect sensory signaling in the gut.Other laboratories have shown that the 5-HT2B receptor participates in the development of mechanical and formalin-induced hyperalgesia[7,8].A 5-HT2B receptor antagonist reduced 2,4,6-trinitrobenzene sulfonic acid(TNBS)and stress-induced visceral hyperalgesia in rats[9,10].However,the role of the 5-HT2B receptor in IBS-D patients and in acetic acid-and wrap restraint-induced IBS-D rat models was not investigated.
基金the Natural Science Foundation of China(31902166,32030104).
文摘Background Serotonin is an important signaling molecule that regulates secretory and sensory functions in the gut.Gut microbiota has been demonstrated to affect serotonin synthesis in rodent models.However,how gut microbes regulate intestinal serotonin production in piglets remains vague.To investigate the relationship between microbiota and serotonin specifically in the colon,microbial composition and serotonin concentration were analyzed in ileum-cannulated piglets subjected to antibiotic infusion from the ileum when comparing with saline infusion.Microbes that correlated positively with serotonin production were isolated from piglet colon and were further used to investi-gate the regulation mechanisms on serotonin production in IPEC-J2 and a putative enterochromaffin cell line RIN-14B cells.Results Antibiotic infusion increased quantities of Lactobacillus amylovorus(LA)that positively correlated with increased serotonin concentrations in the colon,while no effects observed for Limosilactobacillus reuteri(LR).To understand how microbes regulate serotonin,representative strains of LA,LR,and Streptococcus alactolyticus(SA,enriched in feces from prior observation)were selected for cell culture studies.Compared to the control group,LA,LR and SA supernatants significantly up-regulated tryptophan hydroxylase 1(TPH1)expression and promoted serotonin production in IPEC-J2 cells,while in RIN-14B cells only LA exerted similar action.To investigate potential mechanisms mediated by microbe-derived molecules,microbial metabolites including lactate,acetate,glutamine,andγ-aminobutyric acid were selected for cell treatment based on computational and metabolite profiling in bacte-rial supernatant.Among these metabolites,acetate upregulated the expression of free fatty acid receptor 3 and TPH1 while downregulated indoleamine 2,3-dioxygenase 1.Similar effects were also recapitulated when treating the cells with AR420626,an agonist targeting free fatty acid receptor 3.Conclusions Overall,these results suggest that Lactobacillus amylovorus showed a positive correlation with sero-tonin production in the pig gut and exhibited a remarkable ability to regulate serotonin production in cell cultures.These findings provide evidence that microbial metabolites mediate the dialogue between microbes and host,which reveals a potential approach using microbial manipulation to regulate intestinal serotonin biosynthesis.
基金the National Natural Science Foundation of China(32270586,31825019,and 31801322)the Department of Science and Technology of Jiangsu Province(BM2022008-02 and BE2022336).
文摘In animals,serotonin is a neurotransmitter and mood regulator.In plants,serotonin functions in energy acquisition,tissue maintenance,delay of senescence,and response to biotic and abiotic stresses.In this study,we examined the effect of serotonin enrichment of rice endosperm on plant growth,endosperm development,and grain quality.To do so,TDCs and T5H were selected as targets for serotonin fortification.Overexpression of TDC1 or TDC3 increased serotonin accumulation relative to overexpression of T5H in rice grain.Transgenic lines of target genes driven by the Gt1 promoter showed better field performance than those driven by the Ubi promoter.Overexpression of T5H showed little effect on plant growth or grain physicochemical quality.In neuronal cell culture assays,serotonin induced neuroprotective action against apoptosis.Breeding of rice cultivars with high serotonin content may be beneficial for health and nutrition.
文摘<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:""><span style="font-family:Verdana;"> It is not well analyzed whether there are differences in plasma levels of tryptophan (TRP) metabolites between healthy control people (HC) and patients of major monopolar depression (MMD). </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> Ultra high-speed </span></span><span style="font-family:""><span style="font-family:Verdana;">liquid chromatography/mass spectrometry has been used for the simultaneous determination of plasma levels of tryptophan metabolites in depressive </span><span><span style="font-family:Verdana;">patients. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> There are no significant differences between plasma levels of TRP between HC and MMD. Plasma levels of TRP of HC are higher in young men, young women, old men, and old women in this order. Serotonin (5-HT) levels are higher in MMD than HC. Plasma levels of 5-HIAA of HC are also higher than those of patients of MMD. Plasma levels of kynurenine (KYN) of healthy old men and old women are higher than those of young men and old women. Plasma levels of KYN are higher in old women and young men of MMD than those of HC. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> Plasma levels of 5-HT are higher in patients of MMD than those of HC, which may suggest that use of drugs inhibiting the 5-HT transportation may increase plasma levels of 5-HT in MMD.
文摘BACKGROUND Serotonin syndrome(SS)is an underdiagnosed drug-induced clinical syndrome resulting from the excess intrasynaptic concentration of serotonin.Very limited information is available about chronic SS.AIM To evaluate the epidemiological,clinical,and other aspects of the insidious onset SS.METHODS We retrospectively evaluated 14 consecutive adult patients(>18 years)who had complaints for more than 6 wk at the time of consultation and met the Hunter criteria for SS.RESULTS The mean age was 41.1 years(range:21-61 years),with a male preponderance(64%).Although tremors were observed in all patients,this was a presenting complaint in only 43%of patients.Generalized body pain,insomnia,and restlessness were common presenting features(50%each).Other common clinical features were stiffness of the limbs(43%),diaphoresis(43%),gait disturbances(36%),bowel disturbances(36%),dizziness(29%),sexual dysfunctions(21%),incoordination(14%),and fatigue(14%)The mean duration of symptoms before the diagnosis of SS was 13.5±5.8 wk(range:6-24 wk).Amitriptyline was the most common drug(n=6,43%),followed by tramadol(n=5,36%)and sodium valproate(n=5,36%).All patients received cyproheptadine,a 5-hydroxytryptamine2A antagonist,as treatment and noted an excellent response CONCLUSION This study represents the largest study on chronic SS.We suggest that patients receiving serotonergic drugs should be physically examined for the presence of SS upon the development of new symptoms.
基金Supported by the National Natural Science Foundation of China,No.81300272,No.81470796,No.81570489 and No.81570478the Tianjin Research Program of Application Foundation and Advanced Technology of China,No.15JCZDJC36600
文摘Serotonin(5-HT) and the serotonin transporter(SERT) have earned a tremendous amount of attention regarding the pathogenesis of irritable bowel syndrome(IBS). Considering that enteric 5-HT is responsible for the secretion, motility and perception of the bowel, the involvement of altered enteric 5-HT metabolism in the pathogenesis of IBS has been elucidated. Higher 5-HT availability is commonly associated with depressed SERT mR NA in patients with IBS compared with healthy controls. The expression difference of SERT between IBS patients and healthy controls might suggest that SERT plays an essential role in IBS pathogenesis, and SERT was expected to be a novel therapeutic target for IBS. Progress in this area has begun to illuminate the complex regulatory mechanisms of SERT in the etiology of IBS. In this article, current insights regarding the regulation of SERT in IBS are provided, including aspects of SERT gene polymorphisms, microR NAs, immunity and inflammation, gut microbiota, growth factors, among others. Potential SERT-directed therapies for IBS are also described. The potential regulators of SERT are of clinical importance and are important for better understanding IBS pathophysiology and therapeutic strategies.
基金Supported by Innovation Program of the Shanghai Municipal Education Commission,No.12YZ065National Natural Science Foundation of China,No.81072786,No.81473630 and No.81202665+2 种基金Longhua Medical Project,No.D-09High level Project of the University of Educational Commission of Shanghai,China,No.2008GSP19Shanghai Leading Academic Discipline Project,No.J50305
文摘AIM:To determine the molecular mechanisms of Shugan decoction(SGD) in the regulation of colonic motility and visceral hyperalgesia(VHL) in irritable bowel syndrome(IBS).METHODS:The chemical compounds contained in SGD were measured by high-performance liquid chromatography.A rat model of IBS was induced by chronic water avoidance stress(WAS).The number of fecal pellets was counted after WAS and the pain pressure threshold was measured by colorectal distension.Morphological changes in colonic mucosa were detected by hematoxylin-eosin staining.The contents of tumor necrosis factor(TNF)-αin colonic tissue and calcitonin-gene-related peptide(CGRP)in serum were measured by ELISA.The protein expression of serotonin[5-hydroxytryptamide(5-HT)],serotonin transporter(SERT),chromogranin A(Cg A)and CGRP incolon tissue was measured by immunohistochemistry.RESULTS:SGD inhibited colonic motility dysfunction and VHL in rats with IBS.Blockers of transient receptor potential(TRP)vanilloid 1(TRPV1)(Ruthenium Red)and TRP ankyrin-1(TRPA1)(HC-030031)and activator of protease-activated receptor(PAR)4 increased the pain pressure threshold,whereas activators of PAR2and TRPV4 decreased the pain pressure threshold in rats with IBS.The effect of SGD on pain pressure threshold in these rats was abolished by activators of TRPV1(capsaicin),TRPV4(RN1747),TRPA1(Polygodial)and PAR2(AC55541).In addition,CGRP levels in serum and colonic tissue were both increased in these rats.TNF-αlevel in colonic tissue was also significantly upregulated.However,the levels of 5-HT,SERT and Cg A in colonic tissue were decreased.All these pathological changes in rats with IBS were attenuated by SGD.CONCLUSION:SGD alleviated VHL and attenuated colon motility in IBS,partly by regulating TRPV1,TRPV4,TRPA1,PAR2,5-HT,Cg A and SERT,and reducing CGRP and TNF-αlevel.
基金the National Natural Science Foundation of China,No.81570489
文摘AIM To evaluate the effect of Lactobacillus rhamnosus GG supernatant(LGG-s) on the expression of serotonin transporter(SERT) in rats with post-infectious irritable bowel syndrome(PI-IBS).METHODS Campylobacter jejuni 81-176(1010 CFU/m L) was used to induce intestinal infection to develop a PI-IBS model. After evaluation of the post-infectious phase by biochemical tests, Dn A agarose gel electrophoresis, abdominal withdrawal reflex(AWR) test, and the intestinal motility test, four PI-IBS groups received different concentrations of LGG-s for 4 wk. The treatments were maintained for 1.0, 2.0, 3.0 or 4.0 wk during the experiment, and the colons and brains were removed for later use each week. SERT m Rn A and protein levels were detected by real-time PCR and Western blot, respectively.RESULTS The levels of SERT m Rn A and protein in intestinal tissue were higher in rats treated with LGG-s than in control rats and PI-IBS rats gavaged with PBS during the whole study. Undiluted LGG-s up-regulated SERT m Rn A level by 2.67 times compared with the control group by week 2, and SERT m Rn A expression kept increasing later. Double-diluted LGG-s was similar to undiluted-LGG-s, resulting in high levels of SERT m Rn A. Triple-diluted LGG-s up-regulated SERT m Rn A expression level by 6.9-times compared with the control group, but SERT m Rn A expression decreased rapidly at the end of the second week. At the first week, SERT protein levels were basically comparable in rats treated with undiluted LGG-s, double-diluted LGG-s, and triplediluted LGG-s, which were higher than those in the control group and PBS-treated PI-IBS group. SERT protein levels in the intestine were also comparable in rats treated with undiluted LGG-s, double-diluted LGG-s, and triple-diluted LGG-s by the second and third weeks. SERT m Rn A and protein levels in the brain had no statistical difference in the groups during the experiment.CONCLUSION LGG-s can up-regulate SERT m Rn A and protein levels in intestinal tissue but has no influence in brain tissue in rats with PI-IBS.
文摘Given the failure to develop disease-modifying therapies for Alzheimer’s disease(AD),strategies aiming at preventing or delaying the onset of the disease are being prioritized.While the debate regarding whether depression is an etiological risk factor or a prodrome of AD rages on,a key determining factor may be the timing of depression onset in older adults.There is increasing evidence that untreated early-onset depression is a risk factor and that late-onset depression may be a catalyst of cognitive decline.Data from animal studies have shown a beneficial impact of selective serotonin reuptake inhibitors on pathophysiological biomarkers of AD including amyloid burden,tau deposits and neurogenesis.In humans,studies focusing on subjects with a prior history of depression also showed a delay in the onset of AD in those treated with most selective serotonin reuptake inhibitors.Paroxetine,which has strong anticholinergic properties,was associated with increased mortality and mixed effects on amyloid and tau deposits in mice,as well as increased odds of developing AD in humans.Although most of the data regarding selective serotonin reuptake inhibitors is promising,findings should be interpreted cautiously because of notable methodological heterogeneity between studies.There is thus a need to conduct large scale randomized controlled trials with long follow up periods to clarify the dose-effect relationship of specific serotonergic antidepressants on AD prevention.
基金Supported by the National Key Technology Support Program during “12th Five-Year Plan”period of China,No.2014BAI08B00the Leapforward Development Program for Beijing Biopharmaceutical Industry(G20),No. Z171100001717008.
文摘BACKGROUND Visceral hypersensitivity and psychological performance are the main pathophysiological mechanisms of irritable bowel syndrome(IBS).Previous studies have found that cholecystokinin(CCK)can enhance colon movement and that serotonin transporter(SERT)is a transmembrane transport protein with high affinity for 5-hydroxytryptamine,which can rapidly reuptake 5-hydroxytryptamine and then regulate its action time and intensity.We speculate that SERT and CCK might play a role in the pathogenesis of diarrheapredominant IBS(IBS-D)by affecting visceral sensitivity and the brain-gut axis.AIM To determine SERT and CCK levels in IBS-D patients diagnosed using Rome IV criteria and to analyze their associations with abdominal pain,visceral hypersensitivity and psychological performance.METHODS This study collected data from 40 patients with IBS-D at the China-Japan Friendship Hospital from September 2017 to April 2018 and 18 healthy controls.The severity of abdominal pain,visceral sensitivity and psychological performance were evaluated in IBS-D patients and healthy controls,the levels of SERT and CCK in plasma and colonic mucosa were evaluated,and the correlations between them were analyzed.RESULTS There were significant differences in the initial sensation threshold(31.00±8.41 mL vs 52.22±8.09 mL,P<0.001),defecating sensation threshold(51.75±13.57 mL vs 89.44±8.73 mL,P<0.001)and maximum tolerable threshold(97.25±23.64 mL vs 171.11±20.83 mL,P<0.001)between the two groups.IBS-D patients had more severe anxiety(7.78±2.62 vs 2.89±1.02,P<0.001)and depressive(6.38±2.43 vs 2.06±0.73,P<0.001)symptoms than healthy controls.Significant differences were also found in mucosal CCK(2.29±0.30 vs 1.66±0.17,P<0.001)and SERT(1.90±0.51 vs 3.03±0.23,P<0.001)between the two groups.There was a significant positive correlation between pain scores and mucosal CCK(r=0.96,0.93,0.94,P<0.001).Significant negative correlations between anxiety(r=-0.98;P<0.001),depression(r=-0.99;P<0.001),pain evaluation(r=-0.96,-0.93,-0.95,P<0.001)and mucosal SERT were observed.CONCLUSION IBS-D patients had psychosomatic disorders and visceral hypersensitivity.SERT and CCK might be involved in the pathogenesis of IBS-D by regulating the braingut axis and affecting visceral sensitivity.This provides a new potential method for identifying a more specific and effective therapeutic target.
基金supported by grants from the Natural Science Foundation of Shandong Province of China(ZR2011HM023 to GYL)the “11th Five-Year Plan”,National Supporting Program(2007BAI17B02 to GYL)+5 种基金the Science and Technology Project of Higher Education of Shandong Province of China(J10LF01 to GYL)a grant from Medical Science and Technology Development Project of Shandong Province of China(2011HZ011 to GYL)the China Postdoctoral Science Foundation of China(2012M 520585 to CJZ)the Fund of Tianjin Health Bureau of China(2014KR02 to CJZ)the Foundation of Hainan Li Ou Pharmaceutical Co.,Ltd.the Foundation of Xuzhou Enhua Pharmaceutical Co.,Ltd. of China
文摘Previous studies suggest that serotonin(5-HT) might interact with brain-derived neurotrophic factor(BDNF) during the stress response.However,the relationship between 5-HT and BDNF expression under purely psychological stress is unclear.In this study,one hour before psychological stress exposure,the 5-HT1 A receptor agonist 8-OH-DPAT or antagonist MDL73005,or the 5-HT2 A receptor agonist DOI or antagonist ketanserin were administered to rats exposed to psychological stress.Immunohistochemistry and in situ hybridization revealed that after psychological stress,with the exception of the ventral tegmental area,BDNF protein and m RNA expression levels were higher in the 5-HT1 A and the 5-HT2 A receptor agonist groups compared with the solvent control no-stress or psychological stress group in the CA1 and CA3 of the hippocampus,prefrontal cortex,central amygdaloid nucleus,dorsomedial hypothalamic nucleus,dentate gyrus,shell of the nucleus accumbens and the midbrain periaqueductal gray.There was no significant difference between the two agonist groups.In contrast,after stress exposure,BDNF protein and m RNA expression levels were lower in the 5-HT1 A and 5-HT2 A receptor antagonist groups than in the solvent control non-stress group,with the exception of the ventral tegmental area.Our findings suggest that 5-HT regulates BDNF expression in a rat model of acute psychological stress.
基金the German Research Foundation(DFG)grant GA 654/14-1 to OG.
文摘The neuromodulatory transmitter serotonin(5-hydroxytryptamine,5-HT)is synthesized by neurons located in the brainstem,which project more or less densely to the entire central nervous system(Charnay and Leger,2010).Serotonin regulates a variety of physiological functions,including food intake,reward,reproduction,sleep-wake cycle,memory,cognition,emotion,and mood(Charnay and Leger,2010).
基金supported by a grant from the Foundation of School of Medicine of Xi'an Jiaotong University,China(No.2007 YK.2)
文摘BACKGROUND:Liver disease is commonly seen in the clinic and its pathological characteristic is combined hepatocellular death and apoptosis.Promoting hepatocyte regeneration is one of the main methods of treating liver disease.Serotonin(5-HT)is an important compound which participates in various life process,and 95%of it is carried by platelets in the blood.A recent finding showed that platelet-derived serotonin is the key factor in liver regeneration,which fails without serotonin.This study aimed to investigate the effects of quipazine,a selective 5-HT receptor agonist,on proliferation and apoptosis in the human hepatocyte strain L-02. METHODS:L-02 cells were cultured in medium with 5-HT and quipazine,and samples were collected at 24,48,and 72 hours.The methyl thiazolyl tetrazolium(MTT)method was used to test viability,flow cytometry to assess the cell cycle,the Annexin-V/PI method to evaluate apoptosis,and immunohistochemistry to detect proliferating cell nuclear antigen(PCNA). RESULTS:Compared with the control group,the viability of L-02 cells was improved in the 10,50,and 250μg/ml quipazine groups(P<0.05);the percentage of S-phase and PCNA-positive cells were increased in the 2,10,50,and 250μg/ml quipazine groups(P>0.05);and no difference in the percentage of apoptotic cells was found between the 50 μg/ml quipazine and control groups(P>0.05).CONCLUSION:Quipazine improves proliferation of a human hepatocyte strain in vitro,and this is not based on the inhibition of apoptosis.
文摘Angiotensin II (Ang II) is a critical component of the reninangiotensin system that contributes to hypertension. Although platelets in blood from hypertensive subjects have an abnormal biological profile, it is unclear if circulating Ang II influences platelet aggregation or thrombus formation. One of the abnormalities presented to the platelets during hypertension is an elevated plasma concentration of serotonin (5-HT) caused by reduced 5-HT uptake secondary to loss of the 5-HT transporter (SERT) on the platelet plasma membrane. In the current study, we evaluated in vivo platelet function after 7 days of subcutaneous Ang II infusion to establish hypertension in mice and additionally assessed the biology of isolated platelets exposed to Ang II in vitro. The administration of Ang II elevated systolic blood pressure, but markers of platelet activation including P-selectin and PEJon/A staining were not changed. However, the aggregation response to collagen was reduced in isolated platelets from Ang II-infused mice, which also showed reduced 5-HT uptake by SERT. In vitro exposure of isolated platelets to Ang II also resulted in a loss of surface SERT associated with a reduced aggregation response to collagen. These abnormalities were reversed by increasing concentra tions of the Ang II receptor antagonist, valsartan. Interestingly, SERT KO mice failed to fully develop hypertension in response to Ang II infusion and isolated platelets from these animals were insensitive to the anti-aggregatory influence of Ang II. Thus, Ang II blunts the aggregation responses of platelets and the mechanism underlying this action may involve a loss of SERT on the platelet plasma membrane. The latter event depletes intracellular 5-HT in platelets, an event that is associated with reduced aggregation. The widespread use of antihypertensive drugs that target the renin-angiotensin system suggest the potential clinical utility of our findings and emphasize the importance of understanding the impact of Ang II on platelet function.
文摘Previously, we reported that changes induced in autonomic neurotransmission in rats by Lactobacillus brevis SBC8803 may be mediated by serotonin 3 (5-HT3) receptors. In this study, we evaluated the effects of heat-killed L. brevis SBC8803 on serotonin (5-HT) releasing from intestinal cells. In the in vitro study, L. brevis SBC8803 stimulated 5-HT release from cultured rat endocrine RIN-14B cells (SBC8803 vs. sterile water;P in vivo study, 2 mg of heat-killed L. brevis SBC8803 was administered using a stomach sonde (feeding needle) to C57BL/6J mice. Analysis of plasma by ELISA showed gradually increase in 5-HT concentrations (0 min vs. 60 min;P ex vivo cultured intestinal loops composed of duodenum and part of the jejunum, from C3H/HeN and C57BL/6J male mice indicated that L. brevis SBC8803 effectively induced 5-HT release (SBC8803 vs. sterile water;P L. brevis SBC8803 may stimulate 5-HT release from mouse intestinal cells such as enterochromaffin cells.
基金Supported by the National Natural Science Foundation of China,No.81570489and the Youth Project of National Natural Science Foundation of China,No.81900487.
文摘BACKGROUND Bacillus subtilis(B.subtilis),Enterococcus faecium(E.faecium),and Enterococcus faecalis(E.faecalis)are probiotics that are widely used in the clinical treatment of irritable bowel syndrome(IBS).Whether the supernatants of these three probiotics can improve gastrointestinal sensation and movement by regulating the serotonin transporter(SERT)expression needs to be clarified.AIM To investigate whether B.subtilis,E.faecium,and E.faecalis supernatants can upregulate SERT expression in vitro and in vivo.METHODS Caco-2 and HT-29 cells were stimulated with probiotic culture supernatants for 12 and 24 h,respectively.A male Sprague-Dawley rat model of post-infectious irritable bowel syndrome(PI-IBS)was established and the rats were treated with phosphate-buffered saline(group A)and three probiotics culture supernatants(groups B,C,and D)for 4 wk.The levels of SERT were detected by quantitative PCR and western blotting.RESULTS The levels of SERT at post-treatment 12 and 24 h were significantly elevated in Caco-2 cells treated with B.subtilis supernatant compared with those in the control group(aP<0.05).Those levels were markedly upregulated in Caco-2 cells stimulated with E.faecium and E.faecalis supernatants at 24 h(aP<0.05).In addition,SERT expression in groups B,C,and D was significantly higher than that in group A in the 2nd wk(aP<0.05).Increased SERT expression was only found in group D in the 3rd wk(aP<0.05).However,there was no significant difference in SERT expression between the groups in the last week(P>0.05).CONCLUSION The supernatants of B.subtilis,E.faecium,and E.faecalis can upregulate SERT expression in intestinal epithelial cells and the intestinal tissues in the rat model of PI-IBS.
