The clinical significance of a myeloperoxidase (MPO) gene polymorphism and inducible nitric oxide synthase (iNOS) expression in cirrhotic patients with hepatopulmonary syndrome (HPS) was explored. Enrolled subjects we...The clinical significance of a myeloperoxidase (MPO) gene polymorphism and inducible nitric oxide synthase (iNOS) expression in cirrhotic patients with hepatopulmonary syndrome (HPS) was explored. Enrolled subjects were divided into three groups according to their disease/health conditions: the HPS group (cirrhotic patients with HPS; n=63), the non-HPS group (cirrhotic patients without HPS; n=182), and the control group (healthy subjects without liver disease; n=35). The distribution of the MPO-463 G/A genotype and its relationship with iNOS expression in a typical cell block from ascitic fluid were detected by immunohistochemistry and polymerase chain reaction-restricted fragment length polymorphism analysis (PCR-RFLP). In the HPS group, the partial pressure of oxygen in blood and ascitic fluid was significantly decreased (8.95±1.58 kPa and 6.81±0.95 kPa, respectively; both P<0.01), while the partial pressure of carbon dioxide significantly increased (4.62±0.20 kPa and 5.92±0.45 kPa, respectively; P<0.01). MPO and iNOS levels were significantly increased in the HPS group as compared with the non-HPS group. These increases were even more remarkable in ascitic fluid (41.36±11.62 and 13.23±4.81 μg/L; 10.27± 3.20 and 4.95±1.12 μg/L) than in blood (16.66±5.24 and 4.87±1.73 μg/L; 5.79±2.31 and 2.35±0.84 μg/L). The distribution of the MPO genotypes GG, GA, and AA were 76.2%, 22.2% and 1.6% in the HPS group, and 57.7%, 37.9% and 4.4% in the non-HPS group (P<0.05). The expression of iNOS was significantly higher in patients with the G alleles (G/G and G/A) (61.54%, 48/78) than in patients with A alleles (G/A and A/A) (38.46%, 30/78) (P<0.01). It was suggested that the expression levels of iNOS and MPO were correlated with HPS-induced hypoxemia. The MPO-463 G/A mutation might be a protective factor that prevents the development of HPS. The MPO might be involved in the regulation of iNOS expression. In humans, MPO pathways, the iNOS/NO system, and their interaction might have an impact on the occurrence and development of HPS.展开更多
BACKGROUND:Previous studies have shown that inducible nitric oxide synthase(iNOS) and cyclooxygenase 2(COX-2) participate in inflammatory immune responses and neuropathic pain following peripheral nerve injury.However...BACKGROUND:Previous studies have shown that inducible nitric oxide synthase(iNOS) and cyclooxygenase 2(COX-2) participate in inflammatory immune responses and neuropathic pain following peripheral nerve injury.However,few reports have addressed time-dependent expression of iNOS and COX-2 following peripheral nerve injury.OBJECTIVE:To investigate spatiotemporal expression of iNOS and COX-2 during early stage sciatic nerve crush injury.DESIGN,TIME AND SETTING:The randomized,controlled,animal experiment was performed at the Laboratory of Applied Anatomy,Department of Human Anatomy and Neurobiology,Central South University,China from September 2006 to September 2007.MATERIALS:Mouse anti-rat iNOS monoclonal antibody and goat anti-rat COX-2 monoclonal antibody(Transduction Laboratory,USA),as well as biotinylated rabbit anti-mouse IgG and biotinylated rabbit anti-goat IgG(Santa Cruz Biotechnology,USA) were used in the present study.METHODS:A total of 48 healthy,adult,Sprague Dawley rats were randomly assigned to three groups.In the model group(n = 32),crush injury to the right sciatic nerve was established using an artery clamp.The model group was further assigned to four subgroups according to survival time(6,12,24,and 72 hours),respectively(n = 8).Sham surgery(n = 8) and normal control(n = 8) groups were also established.MAIN OUTCOME MEASURES:iNOS and COX-2 expression was detected in the L4-6 spinal cord with immunohistochemistry.Gray values of iNOS-and COX-2-postive cells in the anterior horn and posterior horn of spinal cord,as well as quantification of iNOS-and COX-2-positive cells in the anterior horn of spinal cord,were measured.RESULTS:iNOS and COX-2 expression gradually increased in the anterior horn and posterior horn of the spinal cord on the damaged side over time from 6 hours following sciatic nerve injury(P < 0.05) and peaked at 72 hours.Simultaneously,the number of iNOS-and COX-2-positive cells similarly increased in the anterior horn of spinal cord on the damaged side(P < 0.05).CONCLUSION:iNOS and COX-2 expression increased in the spinal cord during early stage sciatic nerve crush,which suggested that iNOS and COX-2 participate in occurrence and development of inflammatory immune responses following peripheral nerve injury.展开更多
AIM: To clarify the role of inducible nitric oxide synthase(i NOS) in blood-retinal barrier(BRB) injury after acute high intraocular pressure(IOP) in rats.METHODS: Forty-two Sprague-Dawley(SD) rats were randomized int...AIM: To clarify the role of inducible nitric oxide synthase(i NOS) in blood-retinal barrier(BRB) injury after acute high intraocular pressure(IOP) in rats.METHODS: Forty-two Sprague-Dawley(SD) rats were randomized into 7 groups [control(Cont), 3, 6, 12, 24, 48, and 72 h, n=6]. Except Cont group, other groups’ retina tissue was obtained at corresponding time points after a model of acute high IOP have been established in rats. The expression of i NOS and tight junction protein zonula occludens(ZO)-1 was detected by Western blotting. Evans blue(EB;3%) was injected into the great saphenous vein to detect the leakage of EB by spectrophotometer. Nine rats were divided into Cont, 6 h, 12 h groups, the expression of i NOS was localized by immunofluorescence. In order to verify the role of i NOS in the damage to BRB, thirty-six rats were randomly divided into 4 groups [Cont, Cont+inhibitor(Inh), 6 h and 6 h+Inh, n=9]. After treatment with the i NOSspecific inhibitor 1400 W, the expression of i NOS and ZO-1 and the leakage of BRB were detected again.RESULTS: The immunofluorescence results showed that the expression of i NOS was observed in the Cont group and 6 h group, but not in the 12 h group. i NOS was mainly expressed in the retinal nerve fiber layer, ganglion cell layer and inner nuclear layer and that it did not colocalize with the retinal ganglion cell marker Neu N but was co-expressed with the vascular endothelial cell marker CD31. Western blotting showed that in the early period(3 h, 6 h) after acute high IOP, the expression of i NOS was upregulated, then the down-regulation of i NOS were tested in the follow-up timing spots. ZO-1 expression showed a continuous downregulation after 6 h. The quantitative results for EB showed that the amount of EB leakage began to increase at 3 h after acute high IOP. At 6 h, the leakage of EB was lower, but at 12 h, the leakage of EB was highest, after which it gradually recovered but remained higher than that in the Cont group. The expression of i NOS was down-regulated after 1400 W treatment. ZO-1 expression was not significantly changed in the Cont+Inh group and the 6 h group, and significantly down-regulated in the 6 h+Inh group, and the leakage of EB was significantly increased after 1400 W treatment.CONCLUSION: These results suggest that the upregulation of i NOS expression in the early stage after acute high IOP may have a protective effect on BRB injury.展开更多
Pancreatic cancer is a common tumor of the digestive system.At present,the pathogenesis is still unclear,but current research on inducible nitric oxide synthase in relation to the pathogenesis of pancreatic malignant ...Pancreatic cancer is a common tumor of the digestive system.At present,the pathogenesis is still unclear,but current research on inducible nitric oxide synthase in relation to the pathogenesis of pancreatic malignant tumors is particularly extensive.Therefore,this article focuses on the research progress on inducible nitric oxide synthase in the pathogenesis of pancreatic cancer.展开更多
Background:Overexpression of inducible nitric oxide synthase(iNOS)has been reported in diabetic retinopathy(DR).The kinin B1 receptor(B1R)is also overexpressed in DR,and can stimulate iNOS via Gαi/ERK/MAPK pathway.We...Background:Overexpression of inducible nitric oxide synthase(iNOS)has been reported in diabetic retinopathy(DR).The kinin B1 receptor(B1R)is also overexpressed in DR,and can stimulate iNOS via Gαi/ERK/MAPK pathway.We previously showed that the topical administration of a B1R antagonist,LF22-0542,significantly reduces leukocyte infiltration,increased vascular permeability and overexpression of several inflammatory mediators,including iNOS in DR.Thus,the aim of this study was to determine whether the pro-inflammatory effects of B1R are attributed to oxidative stress caused by the activation of iNOS pathway in order to identify new therapeutic targets for the treatment of DR.iNOS and B1R being absent in the normal retina,their inhibition is unlikely to result in undesirable side effects.The approach will be no invasive by eye application of drops.Methods:Diabetes was induced in male Wistar rats(200-230 g)by a single intraperitoneal injection of streptozotocin(STZ,65 mg/kg b.w).One week later,rats were randomly divided into four groups(N=5)and treated for one week as follows:Gr 1:control rats treated with the selective iNOS inhibitor(1,400 W,0.06μM twice a day by eye-drops×7 days),Gr 2,STZ-diabetic rats treated with 1,400 W,Gr 3:control rats received a selective B1R agonist[Sar(D-Phe8)-des-Arg9-BK,100μg twice a week]by intravitreal injections(itrv)and treated with 1,400 W,Gr 4:STZ-diabetic rats+B1R agonist+1,400 W.At the end of treatment and two weeks post-STZ,three series of experiments were carried out to measure vascular permeability(by Evans blue dye method)and the expression of vasoactive and inflammatory mediators,including iNOS,VEGF-A,VEGF-R2,IL-1β,Cox-2,TNF-α,bradykinin 1 and 2 receptors and carboxypeptidase M/kininase 1(by Western Blotting and qRT-PCR).The nitrosative stress(nitrosylation of proteins)was also assessed by Western Blotting.One-way Anova test with Bonferroni post hoc was used for statistical analysis.Results:STZ-diabetic rats showed a significant increase in retinal vascular permeability(22.8μg/g Evans blue dye per g of fresh retinas,P=0.016)compared with control rats and control treated rats(17.2 and 16.8μg/g respectively).The injections of B1R agonist amplified the increase of vascular permeability which was normalized by the 1,400 W.The overexpression of inflammatory markers was also normalized by the 1,400 W in STZ-diabetic rats received or not the B1R agonist.Conclusions:These results support a contribution of iNOS in the deleterious effects of B1R in this model of diabetic retinopathy.Hence,iNOS inhibition by ocular application of 1,400 W may represent a promising and non-invasive therapeutic approach in the treatment of diabetic retinopathy.展开更多
Pancreatic cancer is a common tumor of the digestive system,at present,the pathogenesis is still unclear,but in the current research on the pathogenesis of pancreatic malignant tumors,the research on inducible nitric ...Pancreatic cancer is a common tumor of the digestive system,at present,the pathogenesis is still unclear,but in the current research on the pathogenesis of pancreatic malignant tumors,the research on inducible nitric oxide synthase is particularly extensive.Therefore,this article focuses on the research progress of inducible nitric oxide synthase in the pathogenesis of pancreatic cancer.This is a review.展开更多
AIM: To determine the expressions of inducible nitric oxide synthase (iNOS) and matrix metalloproteinase-9 (MMP-9)in hepatocellular carcinoma (HCC) and to investigate the relationship between iNOS and MMP-9 expression...AIM: To determine the expressions of inducible nitric oxide synthase (iNOS) and matrix metalloproteinase-9 (MMP-9)in hepatocellular carcinoma (HCC) and to investigate the relationship between iNOS and MMP-9 expression and their effects on angiogenesis and progression of HCC.METHODS: Tn this study, we examined iNOS, MMP-9,and CD34 expression in specimens surgically removed from 32 HCC patients and 7 normal liver tissues by immunohistochemical staining. Meanwhile, microvessel density (MVD) was determined as a marker of angiogenesis by counting CD34-positive cells.RESULTS: The positive rates of iNOS and MMP-9expression were 71.88% (23/32) and 78.13% (25/32) in HCC. MMP-g expression was significantly correlated with tumor size, capsule status, TNM stage, and risk of HCC recurrence (P= 0.032, P= 0.033, P= 0.007, and P= 0.001,respectively). There was also a significant relationship between iNOS expression and capsule status and risk of HCC recurrence (P = 0.04g and P = 0.004, respectively),but no correlation between iNOS expression and tumor size and TNM stage. There was a positive association between MVD and TNM stage and risk of HCC recurrence (P = 0.037 and P = 0.000, respectively). The count of MVD was significantly different in different iNOS and MMP-9 immunoreactivity groups (F= 17.713 and 17.097, P = 0.000 and P = 0.000, respectively). The examination of Spearman's rank correlation coefficient showed that there was a significant positive correlation between MVD and iNOS,MMP-9 immunoreactivity (r= 0.754 and 0.751, P= 0.000 and P=0.000, respectively). There was also a significant association between MMP-9 and iNOS expression in HCC (P = 0.010).CONCLUSION: Nitric oxide (NO) produced by iNOS could modulate MMP-9 production and therefore contribute to tumor cell angiogenesis and invasion and metastasis in HCC. The strong expression of iNOS and MMP-9 in HCC may be helpful in evaluating the recurrence of HCC,predicting poor prognosis. For patients with strong expression of MMP-9 and iNOS, the optimal treatment scheme needs to be selected.展开更多
瞄准：与肠的损害在新生的老鼠调查神经元的氮的氧化物 synthase ( nNOS )和可诱导的氮的氧化物 synthase ( i NOS )的动态变化和角色并且定义引起坏死小肠结肠炎( NEC )是否在粘膜与氮的氧化物 synthase ( NOS )的层次被联系影响的肠...瞄准：与肠的损害在新生的老鼠调查神经元的氮的氧化物 synthase ( nNOS )和可诱导的氮的氧化物 synthase ( i NOS )的动态变化和角色并且定义引起坏死小肠结肠炎( NEC )是否在粘膜与氮的氧化物 synthase ( NOS )的层次被联系影响的肠织物。方法：Wistar 老鼠在年龄的不到 24 h 与 5 mg/kg 收到了腹膜内注射脂肪的多糖(LPS ) 。回肠纸巾为 NEC 的组织学的评估并且为 nNOS 和 i NOS 的大小在 1， 3， 6， 12 和 24 h 追随者 LPS 挑战被收集。在肠的损害的度和 NOS 的层次之间的关联是坚定的。结果：注射 LPS 的小狗在损害分数对控制显示出重要增加。nNOS 蛋白质和 mRNA 的表示在 LPS 注射以后被减少。在 nNOS 蛋白质和在 24 h 以内的中部的肠的损害的等级之间有否定重要关联。i NOS 蛋白质和 mRNA 的表示显著地在肠的损害的山峰被增加。结论：nNOS 和 i NOS 在导致 LPS 的肠的损害起不同作用。小心应该在 NEC 有关 NOS 禁止者的潜在的治疗学的使用被施加。展开更多
AIM: Nitric oxide (NO) has been implicated in the pathogenesis of liver cirrhosis. We have found inducible nitric oxide synthase (iNOS) can be induced in hepatocytes of cirrhotic liver. This study further investigated...AIM: Nitric oxide (NO) has been implicated in the pathogenesis of liver cirrhosis. We have found inducible nitric oxide synthase (iNOS) can be induced in hepatocytes of cirrhotic liver. This study further investigated the temporal expression and activity of hepatic iNOS in cirrhosis development.METHODS: Cirrhosis was induced in rats by chronic bile duct ligation (BDL). At different time points after the operation,samples were collected to examine NO concentration, liver function, and morphological changes. Hepatocytes were isolated for determination of iNOS mRNA, protein and enzymatic activity.RESULTS: Histological examination showed early cirrhosis 1-2 wk after BDL, with advanced cirrhosis at 3-4 wk.Bilirubin increased dramatically 3 d after BDL, but decreased by 47% on d 14. Three weeks after BDL, it elevated again. Systemic NO concentration did not increase significantly until 4 wk after BDL, when ascites developed.Hepatocyte iNOS mRNA expression was identified 3 d after BDL, and enhanced with time to 3 wk, but reduced thereafter. iNOS protein showed a similar pattern to mRNA expression. iNOS activity decreased from d 3 to d 7, but increased again thereafter till d 21.CONCLUSION: Hepatic iNOS can be induced in the early stage, which increases with time as cirrhosis develops. Its enzymatic activity is significantly correlated with protein expression and histological alterations of the liver, but not with systemic NO levels, nor with absolute values of liver function markers.展开更多
AIM: To examine the association of inducible nitric oxide synthase (iNOS) C150T polymorphism with gastric cancer, as well as with gastric atrophy and H pylori seropositivity. METHODS: A single nucleotide polymorphism ...AIM: To examine the association of inducible nitric oxide synthase (iNOS) C150T polymorphism with gastric cancer, as well as with gastric atrophy and H pylori seropositivity. METHODS: A single nucleotide polymorphism of iNOS C150T was examined for 454 Japanese health checkup examinees (126 males and 328 females) aged 35 to 85 years without a history of cancer and 202 gastric cancer patients (134 males and 68 females) aged 33 to 94 years with pathologically confirmed diagnosis of gastric adenocarcinoma. RESULTS: The iNOS C150T polymorphism was not associated with gastric atrophy or with H pylori seropositivity. The odds ratio (OR) of the C/T + T/T for gastric cancer was increased without statistical significance (OR=1.19, 95% confidence interval (CI): 0.68-2.08). In the differentiated subgroup (n = 113), however, the OR of the C/T genotype for gastric cancer was significant (OR = 2.02, 95% CI: 1.04-3.92) relative to the C/C genotype. In addition, considering the location of gastric cancer (n = 105), there were significant differences between the controls and non-cardia group with the OR of 2.13 (95% CI: 1.08-4.18) for C/T and 1.94 (95% CI: 1.00-3.78) for C/T + T/T. CONCLUSION: The iNOS C150T polymorphism is associated with the risk of H pylori-related gastric cancerin a Japanese population. This polymorphism may play an important role in increasing the risk of gastric cancer in Asian countires with the highest rates of gastric cancer.展开更多
Objective: To study the expression of the inducible nitric oxide synthase (iNOS) gene and the effects of tumor necrosis factor-α(TNF-a) and interferon-γ(IFN-g)on proliferation of the continuous cultured human colon ...Objective: To study the expression of the inducible nitric oxide synthase (iNOS) gene and the effects of tumor necrosis factor-α(TNF-a) and interferon-γ(IFN-g)on proliferation of the continuous cultured human colon cancer cell line CCL229. Methods: Using the molecular and biochemical techniques and electron microscopy to analyze the expression of iNOS, production of NO and growth characteristics of human colon cancer cells. Results: cytokine treatment can induce expression of the iNOS gene and production of nitric oxide was significantly higher after treatment of CCL229 cells with TNF-αor IFN-γ. Treatment with either cytokine or a combination of both significantly increased levels of Malondialdehyde (MDA) over control. Furthermore, cytokine treatment increased the proliferation inhibition rate as assessed in vitro and decreased the cell proliferation index on flow cytometry. Electron microscopy showed that cells treated with cytokines had fewer pseudopodia or cell processes than control cells and that cytokine treated cells had dilatation of the mitochondria and endoplasmic reticulum and dilated vesicular or tubular cisternae. Conclusion: Our findings indicate that TNF-α and IFN-γ induce the expression of iNOS gene in CCL229 cells, which increases the production of nitric oxide, inhibits proliferation, causes lipid peroxidation, and results in ultrastructural changes.展开更多
AIM: Cydooxygenases (COX) are key enzymes for conversion of arachidonic acid to prostaglandins. Nitric oxide synthase (NOS) is the enzyme responsible for formation of nitric oxide.Both have constitutive and inducible ...AIM: Cydooxygenases (COX) are key enzymes for conversion of arachidonic acid to prostaglandins. Nitric oxide synthase (NOS) is the enzyme responsible for formation of nitric oxide.Both have constitutive and inducible isoforms. The inducible isoforms (iNOS and COX-2) are of great interest as regulators of tumor angiogenesis, tumorigenesis and inflammatory processes. This study was to clarify their role in pancreatic adenocarcinomas.METHODS: We investigated the immunohistochemical iNOS and COX-2 expression in 40 pancreatic ductal adenocarcinomas of different grade and stage. The results were compared with microvessel density and clinicopathological data.RESULTS: Twenty-one (52.5%) of the cases showed iNOS expression, 15 (37.5%) of the cases were positive for COX-2.The immunoreaction was heterogeneously distributed within the tumors. Staining intensity was different between the tumors. No correlation between iNOS and COX-2 expression was seen. There was no relationship with microvessel density.However, iNOS positive tumors developed more often distant metastases and the more malignant tumors showed a higher COX-2 expression. There was no correlation with other clinicopathological data.CONCLUSION: Approximately half of the cases expressed iNOS and COX-2. These two enzymes do not seem to be the key step in angiogenesis or carcinogenesis of pancreatic adenocarcinomas. Due to a low prevalence of COX-2 expression, chemoprevention of pancreatic carcinomas by COX-2 inhibitors can only achieve a limited success.展开更多
OBJECTIVE: To investigate the expression and the role of iNOS expression in hepaticischemia-reperfusion (L/R) injury.METHODS: Male Wistar rats were subjected to 30-minute hepatic ischemia, then iNOS protein andiNOS mR...OBJECTIVE: To investigate the expression and the role of iNOS expression in hepaticischemia-reperfusion (L/R) injury.METHODS: Male Wistar rats were subjected to 30-minute hepatic ischemia, then iNOS protein andiNOS mRNA expression in liver tissue was assessed by Western blot and RT-PCR analysis respectivelyat different time points after reperfusion. The effects of L-NAME (Nω-nitro-L-arginine methyl ester, anonselective NOS inhibitor) or AE-ITU (aminoethytl-isothiourea, a relative selective inhibitor of iNOS)treatment were also evaluated.RESULTS: High levels of iNOS protein and mRNA expression were detected in the liver tissue subjectedto I/R, but not in the sham-operated rats. iNOS protein and iNOS mRNA expression reached a maximumon the first day after reperfusion and decreased later. The levels of iNOS protein and iNOS mRNAdisappeared on 7th, 3rd day after reperfusion respectively. The high iNOS expression was correlated withhepatic dysfunction. L-NAME administration worsened hepatic dysfunction induced by hepatic I/R. Incontrast, AE-ITU administration showed mild protective effects against hepatic dysfunction induced byhepatic I/R.CONCLUSION: Ischemia-reperfusion may induce or up-regulate the expression of iNOS protein andiNOS mRNA, which is detrimental to hepatic I/R injury.展开更多
In this study,we examined the expression of inducible nitric oxide synthase(iNOS) and vascular endothelial growth factor(VEGF) by immunohistochemical staining in 76 tissue sections collected from bepa-tocellular carci...In this study,we examined the expression of inducible nitric oxide synthase(iNOS) and vascular endothelial growth factor(VEGF) by immunohistochemical staining in 76 tissue sections collected from bepa-tocellular carcinoma(HCC) patients undergoing hepatectomy.Microvascular density (MVD) was determined by counting endothelial cells immunostained using anti-CD34 antibody.We performed DNA-flow cytometric analyses to elucidate the impact of iNOS and VEGF expression on the cell cycle of HCC.Most of the HCC cells that invaded stroma were markedly immunostained by iNOS antibody.The iNOS stain intensity of the liv-er tissue close to the tumor edge was stronger than that of HCC tissue,and the strongest was the hepatocytes colser to the tumor tissue.However,iNOS expression in 10 normal hepatic samples was undetectable.VEGF positive expression ratio was 84.8% in iNOS positive expression cases,and the ratio was 35.3% in negative cases.There was significant correlation(P=0.000) between iNOS and VEGF expression.Moreover,iNOS expression was significantly associated with bcl-2 and MVD,but without p53 expression.DNA-flow cytometric analyses showed that combined expression of iNOS and VEGF had significant impact on the cell cycle in HCC.PI(Proliferating Index) and SPF(S-phase fraction)in the combined positive expression of iNOS and VEGF group was significantly higher than that in the combined negative group.The present findings suggested that iNOS expression was significantly associated with angiogenesis,bcl-2 and cell proliferation of HCC.展开更多
It is reported that inducible nitric oxide synthase (iNOS) plays an important role in rejection. This study was designed to observe the expression of iNOS in the transplanted liver tissues and the effect of aminoguani...It is reported that inducible nitric oxide synthase (iNOS) plays an important role in rejection. This study was designed to observe the expression of iNOS in the transplanted liver tissues and the effect of aminoguanidine (an inhibitor of iNOS) and FK506 (immunosuppression) on acute rejection after liver transplantation. METHODS:All rats were divided into four groups:homogeneous (LEW-LEW), acute rejection (BN-LEW), aminoguanidine (BN-LEW), and FK506 (BN-LEW). In the last two groups the drugs were used in heterogeneous rats after liver transplantation.The expression of iNOS in liver tissues of all groups was investigated immunohistochemically. RESULTS:In the acute rejection group, the expression of iNOS was extremely positive compared to the other three groups. The difference was statistically significant. CONCLUSIONS:During the process of acute rejection in rat orthotopic liver transplantation, the enhanced expression of iNOS correlates to the severity of rejection. Aminoguanidine and FK506 can inhibit the expression of iNOS and palliate acute rejection.展开更多
AIM:To investigate the effect of prednisolone,a synthetic glucocorticoid used in inflammatory diseases,on the growth of cultured osteosarcoma cells.METHODS:Two osteosarcoma cell lines with different degree of differen...AIM:To investigate the effect of prednisolone,a synthetic glucocorticoid used in inflammatory diseases,on the growth of cultured osteosarcoma cells.METHODS:Two osteosarcoma cell lines with different degree of differentiation were used.SaOS2 show a rather mature phenotype,while U2 OS are negative for almost all osteoblastic markers.The cells were exposed to different concentrations of prednisolone(1-9 μmol/L) with or without antioxidants or the inhibitor of inducible nitric oxide synthase(i NOS) l-N6-(iminoethyl)-lysine-HCl(L-NIL).Cell growth was assessed by counting viable cells.The production of nitric oxide(NO) was measured in the conditioned media by the Griess method.The production of reactive oxygen species was quantified using 2'-7'-dichlorofluorescein diacetate.Western blot with specific antibodies against NOSs was performed on cell extracts.RESULTS:Prednisolone inhibited SaOS2 cell growth in a dose dependent manner.No significant effects were observed in U2OS.The inhibition of SaOS2 growth is not due to oxidative stress,because antioxidants do not rescue cell proliferation.Since high concentrations of NO inhibit bone formation,we also measured NO and found it induced in SaOS2,but not in U2 OS,exposed to prednisolone,because of the upregulation of i NOS as detected by western blot.Therefore,we treated SaOS2 with prednisolone in the presence or in the absence of L-NIL.L-NIL prevented NO release induced by prednisolone at all the concentrations apart from 9 μmol/L.At the same concentrations,we found that L-NIL rescued SaOS2 growth after exposure to prednisolone.In U2 OS cells,prednisolone did not induce NO production nor affected cell growth.All together,these data indicate that a link exists between increased amounts of NO and growth inhibition in response to prednisolone in SaOS2.CONCLUSION:Prednisolone inhibited SaOS2 proliferation by increasing the release of NO through the upregulation of i NOS,while no effect was exerted on U2OS.展开更多
The present study detected distribution and expression of nerve growth factor and inducible nitric oxide synthase in the mesencephalon and diencephalon, as well as visual- and auditory-related nervous tissues, in a ma...The present study detected distribution and expression of nerve growth factor and inducible nitric oxide synthase in the mesencephalon and diencephalon, as well as visual- and auditory-related nervous tissues, in a macaque model of type 2 diabetes using immunohistochemistry. Results showed that nerve growth factor expression decreased, but inducible nitric oxide synthase expression increased, in the mesencephalon and diencephalon, as well as visual- and auditory- related nervous tissues. These results suggested that nerve growth factor and inducible nitric oxide synthase play an important role in regulating the development of diabetic visual- and auditory-related diseases.展开更多
基金supported by a grant from Heilongjiang Provincial Science and Technology Breakthrough Project Foundation (No. GB07C32506)
文摘The clinical significance of a myeloperoxidase (MPO) gene polymorphism and inducible nitric oxide synthase (iNOS) expression in cirrhotic patients with hepatopulmonary syndrome (HPS) was explored. Enrolled subjects were divided into three groups according to their disease/health conditions: the HPS group (cirrhotic patients with HPS; n=63), the non-HPS group (cirrhotic patients without HPS; n=182), and the control group (healthy subjects without liver disease; n=35). The distribution of the MPO-463 G/A genotype and its relationship with iNOS expression in a typical cell block from ascitic fluid were detected by immunohistochemistry and polymerase chain reaction-restricted fragment length polymorphism analysis (PCR-RFLP). In the HPS group, the partial pressure of oxygen in blood and ascitic fluid was significantly decreased (8.95±1.58 kPa and 6.81±0.95 kPa, respectively; both P<0.01), while the partial pressure of carbon dioxide significantly increased (4.62±0.20 kPa and 5.92±0.45 kPa, respectively; P<0.01). MPO and iNOS levels were significantly increased in the HPS group as compared with the non-HPS group. These increases were even more remarkable in ascitic fluid (41.36±11.62 and 13.23±4.81 μg/L; 10.27± 3.20 and 4.95±1.12 μg/L) than in blood (16.66±5.24 and 4.87±1.73 μg/L; 5.79±2.31 and 2.35±0.84 μg/L). The distribution of the MPO genotypes GG, GA, and AA were 76.2%, 22.2% and 1.6% in the HPS group, and 57.7%, 37.9% and 4.4% in the non-HPS group (P<0.05). The expression of iNOS was significantly higher in patients with the G alleles (G/G and G/A) (61.54%, 48/78) than in patients with A alleles (G/A and A/A) (38.46%, 30/78) (P<0.01). It was suggested that the expression levels of iNOS and MPO were correlated with HPS-induced hypoxemia. The MPO-463 G/A mutation might be a protective factor that prevents the development of HPS. The MPO might be involved in the regulation of iNOS expression. In humans, MPO pathways, the iNOS/NO system, and their interaction might have an impact on the occurrence and development of HPS.
基金the National Natural Science Foundation of China,No. 30860290the Scientific Research Foundation of Department of Health of Hunan Province of China,No. C2007038+2 种基金the Scientific Research Program of Department of Education of Hunan Province,No. 08C816the Nanometer Specific Foundation of Shanghai of China,No. 1052nm05800the Doctor Innovation Foundation of Medical College of Shanghai Jiao Tong University of China,No. BXJ201043
文摘BACKGROUND:Previous studies have shown that inducible nitric oxide synthase(iNOS) and cyclooxygenase 2(COX-2) participate in inflammatory immune responses and neuropathic pain following peripheral nerve injury.However,few reports have addressed time-dependent expression of iNOS and COX-2 following peripheral nerve injury.OBJECTIVE:To investigate spatiotemporal expression of iNOS and COX-2 during early stage sciatic nerve crush injury.DESIGN,TIME AND SETTING:The randomized,controlled,animal experiment was performed at the Laboratory of Applied Anatomy,Department of Human Anatomy and Neurobiology,Central South University,China from September 2006 to September 2007.MATERIALS:Mouse anti-rat iNOS monoclonal antibody and goat anti-rat COX-2 monoclonal antibody(Transduction Laboratory,USA),as well as biotinylated rabbit anti-mouse IgG and biotinylated rabbit anti-goat IgG(Santa Cruz Biotechnology,USA) were used in the present study.METHODS:A total of 48 healthy,adult,Sprague Dawley rats were randomly assigned to three groups.In the model group(n = 32),crush injury to the right sciatic nerve was established using an artery clamp.The model group was further assigned to four subgroups according to survival time(6,12,24,and 72 hours),respectively(n = 8).Sham surgery(n = 8) and normal control(n = 8) groups were also established.MAIN OUTCOME MEASURES:iNOS and COX-2 expression was detected in the L4-6 spinal cord with immunohistochemistry.Gray values of iNOS-and COX-2-postive cells in the anterior horn and posterior horn of spinal cord,as well as quantification of iNOS-and COX-2-positive cells in the anterior horn of spinal cord,were measured.RESULTS:iNOS and COX-2 expression gradually increased in the anterior horn and posterior horn of the spinal cord on the damaged side over time from 6 hours following sciatic nerve injury(P < 0.05) and peaked at 72 hours.Simultaneously,the number of iNOS-and COX-2-positive cells similarly increased in the anterior horn of spinal cord on the damaged side(P < 0.05).CONCLUSION:iNOS and COX-2 expression increased in the spinal cord during early stage sciatic nerve crush,which suggested that iNOS and COX-2 participate in occurrence and development of inflammatory immune responses following peripheral nerve injury.
基金Supported by the National Natural Science(No.81660217)National College Students Innovation and Entrepreneurship Training Program Project (No.201911810004)。
文摘AIM: To clarify the role of inducible nitric oxide synthase(i NOS) in blood-retinal barrier(BRB) injury after acute high intraocular pressure(IOP) in rats.METHODS: Forty-two Sprague-Dawley(SD) rats were randomized into 7 groups [control(Cont), 3, 6, 12, 24, 48, and 72 h, n=6]. Except Cont group, other groups’ retina tissue was obtained at corresponding time points after a model of acute high IOP have been established in rats. The expression of i NOS and tight junction protein zonula occludens(ZO)-1 was detected by Western blotting. Evans blue(EB;3%) was injected into the great saphenous vein to detect the leakage of EB by spectrophotometer. Nine rats were divided into Cont, 6 h, 12 h groups, the expression of i NOS was localized by immunofluorescence. In order to verify the role of i NOS in the damage to BRB, thirty-six rats were randomly divided into 4 groups [Cont, Cont+inhibitor(Inh), 6 h and 6 h+Inh, n=9]. After treatment with the i NOSspecific inhibitor 1400 W, the expression of i NOS and ZO-1 and the leakage of BRB were detected again.RESULTS: The immunofluorescence results showed that the expression of i NOS was observed in the Cont group and 6 h group, but not in the 12 h group. i NOS was mainly expressed in the retinal nerve fiber layer, ganglion cell layer and inner nuclear layer and that it did not colocalize with the retinal ganglion cell marker Neu N but was co-expressed with the vascular endothelial cell marker CD31. Western blotting showed that in the early period(3 h, 6 h) after acute high IOP, the expression of i NOS was upregulated, then the down-regulation of i NOS were tested in the follow-up timing spots. ZO-1 expression showed a continuous downregulation after 6 h. The quantitative results for EB showed that the amount of EB leakage began to increase at 3 h after acute high IOP. At 6 h, the leakage of EB was lower, but at 12 h, the leakage of EB was highest, after which it gradually recovered but remained higher than that in the Cont group. The expression of i NOS was down-regulated after 1400 W treatment. ZO-1 expression was not significantly changed in the Cont+Inh group and the 6 h group, and significantly down-regulated in the 6 h+Inh group, and the leakage of EB was significantly increased after 1400 W treatment.CONCLUSION: These results suggest that the upregulation of i NOS expression in the early stage after acute high IOP may have a protective effect on BRB injury.
文摘Pancreatic cancer is a common tumor of the digestive system.At present,the pathogenesis is still unclear,but current research on inducible nitric oxide synthase in relation to the pathogenesis of pancreatic malignant tumors is particularly extensive.Therefore,this article focuses on the research progress on inducible nitric oxide synthase in the pathogenesis of pancreatic cancer.
文摘Background:Overexpression of inducible nitric oxide synthase(iNOS)has been reported in diabetic retinopathy(DR).The kinin B1 receptor(B1R)is also overexpressed in DR,and can stimulate iNOS via Gαi/ERK/MAPK pathway.We previously showed that the topical administration of a B1R antagonist,LF22-0542,significantly reduces leukocyte infiltration,increased vascular permeability and overexpression of several inflammatory mediators,including iNOS in DR.Thus,the aim of this study was to determine whether the pro-inflammatory effects of B1R are attributed to oxidative stress caused by the activation of iNOS pathway in order to identify new therapeutic targets for the treatment of DR.iNOS and B1R being absent in the normal retina,their inhibition is unlikely to result in undesirable side effects.The approach will be no invasive by eye application of drops.Methods:Diabetes was induced in male Wistar rats(200-230 g)by a single intraperitoneal injection of streptozotocin(STZ,65 mg/kg b.w).One week later,rats were randomly divided into four groups(N=5)and treated for one week as follows:Gr 1:control rats treated with the selective iNOS inhibitor(1,400 W,0.06μM twice a day by eye-drops×7 days),Gr 2,STZ-diabetic rats treated with 1,400 W,Gr 3:control rats received a selective B1R agonist[Sar(D-Phe8)-des-Arg9-BK,100μg twice a week]by intravitreal injections(itrv)and treated with 1,400 W,Gr 4:STZ-diabetic rats+B1R agonist+1,400 W.At the end of treatment and two weeks post-STZ,three series of experiments were carried out to measure vascular permeability(by Evans blue dye method)and the expression of vasoactive and inflammatory mediators,including iNOS,VEGF-A,VEGF-R2,IL-1β,Cox-2,TNF-α,bradykinin 1 and 2 receptors and carboxypeptidase M/kininase 1(by Western Blotting and qRT-PCR).The nitrosative stress(nitrosylation of proteins)was also assessed by Western Blotting.One-way Anova test with Bonferroni post hoc was used for statistical analysis.Results:STZ-diabetic rats showed a significant increase in retinal vascular permeability(22.8μg/g Evans blue dye per g of fresh retinas,P=0.016)compared with control rats and control treated rats(17.2 and 16.8μg/g respectively).The injections of B1R agonist amplified the increase of vascular permeability which was normalized by the 1,400 W.The overexpression of inflammatory markers was also normalized by the 1,400 W in STZ-diabetic rats received or not the B1R agonist.Conclusions:These results support a contribution of iNOS in the deleterious effects of B1R in this model of diabetic retinopathy.Hence,iNOS inhibition by ocular application of 1,400 W may represent a promising and non-invasive therapeutic approach in the treatment of diabetic retinopathy.
文摘Pancreatic cancer is a common tumor of the digestive system,at present,the pathogenesis is still unclear,but in the current research on the pathogenesis of pancreatic malignant tumors,the research on inducible nitric oxide synthase is particularly extensive.Therefore,this article focuses on the research progress of inducible nitric oxide synthase in the pathogenesis of pancreatic cancer.This is a review.
文摘AIM: To determine the expressions of inducible nitric oxide synthase (iNOS) and matrix metalloproteinase-9 (MMP-9)in hepatocellular carcinoma (HCC) and to investigate the relationship between iNOS and MMP-9 expression and their effects on angiogenesis and progression of HCC.METHODS: Tn this study, we examined iNOS, MMP-9,and CD34 expression in specimens surgically removed from 32 HCC patients and 7 normal liver tissues by immunohistochemical staining. Meanwhile, microvessel density (MVD) was determined as a marker of angiogenesis by counting CD34-positive cells.RESULTS: The positive rates of iNOS and MMP-9expression were 71.88% (23/32) and 78.13% (25/32) in HCC. MMP-g expression was significantly correlated with tumor size, capsule status, TNM stage, and risk of HCC recurrence (P= 0.032, P= 0.033, P= 0.007, and P= 0.001,respectively). There was also a significant relationship between iNOS expression and capsule status and risk of HCC recurrence (P = 0.04g and P = 0.004, respectively),but no correlation between iNOS expression and tumor size and TNM stage. There was a positive association between MVD and TNM stage and risk of HCC recurrence (P = 0.037 and P = 0.000, respectively). The count of MVD was significantly different in different iNOS and MMP-9 immunoreactivity groups (F= 17.713 and 17.097, P = 0.000 and P = 0.000, respectively). The examination of Spearman's rank correlation coefficient showed that there was a significant positive correlation between MVD and iNOS,MMP-9 immunoreactivity (r= 0.754 and 0.751, P= 0.000 and P=0.000, respectively). There was also a significant association between MMP-9 and iNOS expression in HCC (P = 0.010).CONCLUSION: Nitric oxide (NO) produced by iNOS could modulate MMP-9 production and therefore contribute to tumor cell angiogenesis and invasion and metastasis in HCC. The strong expression of iNOS and MMP-9 in HCC may be helpful in evaluating the recurrence of HCC,predicting poor prognosis. For patients with strong expression of MMP-9 and iNOS, the optimal treatment scheme needs to be selected.
文摘瞄准：与肠的损害在新生的老鼠调查神经元的氮的氧化物 synthase ( nNOS )和可诱导的氮的氧化物 synthase ( i NOS )的动态变化和角色并且定义引起坏死小肠结肠炎( NEC )是否在粘膜与氮的氧化物 synthase ( NOS )的层次被联系影响的肠织物。方法：Wistar 老鼠在年龄的不到 24 h 与 5 mg/kg 收到了腹膜内注射脂肪的多糖(LPS ) 。回肠纸巾为 NEC 的组织学的评估并且为 nNOS 和 i NOS 的大小在 1， 3， 6， 12 和 24 h 追随者 LPS 挑战被收集。在肠的损害的度和 NOS 的层次之间的关联是坚定的。结果：注射 LPS 的小狗在损害分数对控制显示出重要增加。nNOS 蛋白质和 mRNA 的表示在 LPS 注射以后被减少。在 nNOS 蛋白质和在 24 h 以内的中部的肠的损害的等级之间有否定重要关联。i NOS 蛋白质和 mRNA 的表示显著地在肠的损害的山峰被增加。结论：nNOS 和 i NOS 在导致 LPS 的肠的损害起不同作用。小心应该在 NEC 有关 NOS 禁止者的潜在的治疗学的使用被施加。
文摘AIM: Nitric oxide (NO) has been implicated in the pathogenesis of liver cirrhosis. We have found inducible nitric oxide synthase (iNOS) can be induced in hepatocytes of cirrhotic liver. This study further investigated the temporal expression and activity of hepatic iNOS in cirrhosis development.METHODS: Cirrhosis was induced in rats by chronic bile duct ligation (BDL). At different time points after the operation,samples were collected to examine NO concentration, liver function, and morphological changes. Hepatocytes were isolated for determination of iNOS mRNA, protein and enzymatic activity.RESULTS: Histological examination showed early cirrhosis 1-2 wk after BDL, with advanced cirrhosis at 3-4 wk.Bilirubin increased dramatically 3 d after BDL, but decreased by 47% on d 14. Three weeks after BDL, it elevated again. Systemic NO concentration did not increase significantly until 4 wk after BDL, when ascites developed.Hepatocyte iNOS mRNA expression was identified 3 d after BDL, and enhanced with time to 3 wk, but reduced thereafter. iNOS protein showed a similar pattern to mRNA expression. iNOS activity decreased from d 3 to d 7, but increased again thereafter till d 21.CONCLUSION: Hepatic iNOS can be induced in the early stage, which increases with time as cirrhosis develops. Its enzymatic activity is significantly correlated with protein expression and histological alterations of the liver, but not with systemic NO levels, nor with absolute values of liver function markers.
基金Supported by a Grant-in-Aid for Scientific Research on Special Priority Areas of Cancer from the Japanese Ministry of Education, Culture, Sports, Science and Technology
文摘AIM: To examine the association of inducible nitric oxide synthase (iNOS) C150T polymorphism with gastric cancer, as well as with gastric atrophy and H pylori seropositivity. METHODS: A single nucleotide polymorphism of iNOS C150T was examined for 454 Japanese health checkup examinees (126 males and 328 females) aged 35 to 85 years without a history of cancer and 202 gastric cancer patients (134 males and 68 females) aged 33 to 94 years with pathologically confirmed diagnosis of gastric adenocarcinoma. RESULTS: The iNOS C150T polymorphism was not associated with gastric atrophy or with H pylori seropositivity. The odds ratio (OR) of the C/T + T/T for gastric cancer was increased without statistical significance (OR=1.19, 95% confidence interval (CI): 0.68-2.08). In the differentiated subgroup (n = 113), however, the OR of the C/T genotype for gastric cancer was significant (OR = 2.02, 95% CI: 1.04-3.92) relative to the C/C genotype. In addition, considering the location of gastric cancer (n = 105), there were significant differences between the controls and non-cardia group with the OR of 2.13 (95% CI: 1.08-4.18) for C/T and 1.94 (95% CI: 1.00-3.78) for C/T + T/T. CONCLUSION: The iNOS C150T polymorphism is associated with the risk of H pylori-related gastric cancerin a Japanese population. This polymorphism may play an important role in increasing the risk of gastric cancer in Asian countires with the highest rates of gastric cancer.
基金This work was supported by a grant from the Scientific Research Foundation of Ministry of Public Health of PR China (No. 96-1-204).
文摘Objective: To study the expression of the inducible nitric oxide synthase (iNOS) gene and the effects of tumor necrosis factor-α(TNF-a) and interferon-γ(IFN-g)on proliferation of the continuous cultured human colon cancer cell line CCL229. Methods: Using the molecular and biochemical techniques and electron microscopy to analyze the expression of iNOS, production of NO and growth characteristics of human colon cancer cells. Results: cytokine treatment can induce expression of the iNOS gene and production of nitric oxide was significantly higher after treatment of CCL229 cells with TNF-αor IFN-γ. Treatment with either cytokine or a combination of both significantly increased levels of Malondialdehyde (MDA) over control. Furthermore, cytokine treatment increased the proliferation inhibition rate as assessed in vitro and decreased the cell proliferation index on flow cytometry. Electron microscopy showed that cells treated with cytokines had fewer pseudopodia or cell processes than control cells and that cytokine treated cells had dilatation of the mitochondria and endoplasmic reticulum and dilated vesicular or tubular cisternae. Conclusion: Our findings indicate that TNF-α and IFN-γ induce the expression of iNOS gene in CCL229 cells, which increases the production of nitric oxide, inhibits proliferation, causes lipid peroxidation, and results in ultrastructural changes.
文摘AIM: Cydooxygenases (COX) are key enzymes for conversion of arachidonic acid to prostaglandins. Nitric oxide synthase (NOS) is the enzyme responsible for formation of nitric oxide.Both have constitutive and inducible isoforms. The inducible isoforms (iNOS and COX-2) are of great interest as regulators of tumor angiogenesis, tumorigenesis and inflammatory processes. This study was to clarify their role in pancreatic adenocarcinomas.METHODS: We investigated the immunohistochemical iNOS and COX-2 expression in 40 pancreatic ductal adenocarcinomas of different grade and stage. The results were compared with microvessel density and clinicopathological data.RESULTS: Twenty-one (52.5%) of the cases showed iNOS expression, 15 (37.5%) of the cases were positive for COX-2.The immunoreaction was heterogeneously distributed within the tumors. Staining intensity was different between the tumors. No correlation between iNOS and COX-2 expression was seen. There was no relationship with microvessel density.However, iNOS positive tumors developed more often distant metastases and the more malignant tumors showed a higher COX-2 expression. There was no correlation with other clinicopathological data.CONCLUSION: Approximately half of the cases expressed iNOS and COX-2. These two enzymes do not seem to be the key step in angiogenesis or carcinogenesis of pancreatic adenocarcinomas. Due to a low prevalence of COX-2 expression, chemoprevention of pancreatic carcinomas by COX-2 inhibitors can only achieve a limited success.
基金This study was supported partly by the Grant-In-Aid for Scientific Research from the Ministry of Education, Science and Culture of Japan (No. 11470334) to M.Takeda.
文摘OBJECTIVE: To investigate the expression and the role of iNOS expression in hepaticischemia-reperfusion (L/R) injury.METHODS: Male Wistar rats were subjected to 30-minute hepatic ischemia, then iNOS protein andiNOS mRNA expression in liver tissue was assessed by Western blot and RT-PCR analysis respectivelyat different time points after reperfusion. The effects of L-NAME (Nω-nitro-L-arginine methyl ester, anonselective NOS inhibitor) or AE-ITU (aminoethytl-isothiourea, a relative selective inhibitor of iNOS)treatment were also evaluated.RESULTS: High levels of iNOS protein and mRNA expression were detected in the liver tissue subjectedto I/R, but not in the sham-operated rats. iNOS protein and iNOS mRNA expression reached a maximumon the first day after reperfusion and decreased later. The levels of iNOS protein and iNOS mRNAdisappeared on 7th, 3rd day after reperfusion respectively. The high iNOS expression was correlated withhepatic dysfunction. L-NAME administration worsened hepatic dysfunction induced by hepatic I/R. Incontrast, AE-ITU administration showed mild protective effects against hepatic dysfunction induced byhepatic I/R.CONCLUSION: Ischemia-reperfusion may induce or up-regulate the expression of iNOS protein andiNOS mRNA, which is detrimental to hepatic I/R injury.
文摘In this study,we examined the expression of inducible nitric oxide synthase(iNOS) and vascular endothelial growth factor(VEGF) by immunohistochemical staining in 76 tissue sections collected from bepa-tocellular carcinoma(HCC) patients undergoing hepatectomy.Microvascular density (MVD) was determined by counting endothelial cells immunostained using anti-CD34 antibody.We performed DNA-flow cytometric analyses to elucidate the impact of iNOS and VEGF expression on the cell cycle of HCC.Most of the HCC cells that invaded stroma were markedly immunostained by iNOS antibody.The iNOS stain intensity of the liv-er tissue close to the tumor edge was stronger than that of HCC tissue,and the strongest was the hepatocytes colser to the tumor tissue.However,iNOS expression in 10 normal hepatic samples was undetectable.VEGF positive expression ratio was 84.8% in iNOS positive expression cases,and the ratio was 35.3% in negative cases.There was significant correlation(P=0.000) between iNOS and VEGF expression.Moreover,iNOS expression was significantly associated with bcl-2 and MVD,but without p53 expression.DNA-flow cytometric analyses showed that combined expression of iNOS and VEGF had significant impact on the cell cycle in HCC.PI(Proliferating Index) and SPF(S-phase fraction)in the combined positive expression of iNOS and VEGF group was significantly higher than that in the combined negative group.The present findings suggested that iNOS expression was significantly associated with angiogenesis,bcl-2 and cell proliferation of HCC.
文摘It is reported that inducible nitric oxide synthase (iNOS) plays an important role in rejection. This study was designed to observe the expression of iNOS in the transplanted liver tissues and the effect of aminoguanidine (an inhibitor of iNOS) and FK506 (immunosuppression) on acute rejection after liver transplantation. METHODS:All rats were divided into four groups:homogeneous (LEW-LEW), acute rejection (BN-LEW), aminoguanidine (BN-LEW), and FK506 (BN-LEW). In the last two groups the drugs were used in heterogeneous rats after liver transplantation.The expression of iNOS in liver tissues of all groups was investigated immunohistochemically. RESULTS:In the acute rejection group, the expression of iNOS was extremely positive compared to the other three groups. The difference was statistically significant. CONCLUSIONS:During the process of acute rejection in rat orthotopic liver transplantation, the enhanced expression of iNOS correlates to the severity of rejection. Aminoguanidine and FK506 can inhibit the expression of iNOS and palliate acute rejection.
文摘AIM:To investigate the effect of prednisolone,a synthetic glucocorticoid used in inflammatory diseases,on the growth of cultured osteosarcoma cells.METHODS:Two osteosarcoma cell lines with different degree of differentiation were used.SaOS2 show a rather mature phenotype,while U2 OS are negative for almost all osteoblastic markers.The cells were exposed to different concentrations of prednisolone(1-9 μmol/L) with or without antioxidants or the inhibitor of inducible nitric oxide synthase(i NOS) l-N6-(iminoethyl)-lysine-HCl(L-NIL).Cell growth was assessed by counting viable cells.The production of nitric oxide(NO) was measured in the conditioned media by the Griess method.The production of reactive oxygen species was quantified using 2'-7'-dichlorofluorescein diacetate.Western blot with specific antibodies against NOSs was performed on cell extracts.RESULTS:Prednisolone inhibited SaOS2 cell growth in a dose dependent manner.No significant effects were observed in U2OS.The inhibition of SaOS2 growth is not due to oxidative stress,because antioxidants do not rescue cell proliferation.Since high concentrations of NO inhibit bone formation,we also measured NO and found it induced in SaOS2,but not in U2 OS,exposed to prednisolone,because of the upregulation of i NOS as detected by western blot.Therefore,we treated SaOS2 with prednisolone in the presence or in the absence of L-NIL.L-NIL prevented NO release induced by prednisolone at all the concentrations apart from 9 μmol/L.At the same concentrations,we found that L-NIL rescued SaOS2 growth after exposure to prednisolone.In U2 OS cells,prednisolone did not induce NO production nor affected cell growth.All together,these data indicate that a link exists between increased amounts of NO and growth inhibition in response to prednisolone in SaOS2.CONCLUSION:Prednisolone inhibited SaOS2 proliferation by increasing the release of NO through the upregulation of i NOS,while no effect was exerted on U2OS.
基金supported by the Program for Changjiang Scholars and Innovative Research Teaming University, No. IRT0848Sichuan Province International Technology Cooperation and Communication Research Programs, No. 2010HH0013+2 种基金Sichuan Province Basic Research Program, No. 2011JY0054the National Key Research Program of China, No. 2011ZX09301-001, 2011ZX09307-301-3Science and Technology Support Programs of Sichuan Province, No. 2011JO0040, 2011ZO0034
文摘The present study detected distribution and expression of nerve growth factor and inducible nitric oxide synthase in the mesencephalon and diencephalon, as well as visual- and auditory-related nervous tissues, in a macaque model of type 2 diabetes using immunohistochemistry. Results showed that nerve growth factor expression decreased, but inducible nitric oxide synthase expression increased, in the mesencephalon and diencephalon, as well as visual- and auditory- related nervous tissues. These results suggested that nerve growth factor and inducible nitric oxide synthase play an important role in regulating the development of diabetic visual- and auditory-related diseases.
