【Abstract】ObjectiveTo investigate the protective effect of melatonin on renal injury induced by bile duct ligation in rats. MethodsSixtyfour rats were randomly divided into four experimental groups (n=16 rats per group): the control group (CN), sham operative group (SO), bile duct ligation group (BDL) and bile duct ligation melatonin treatment group (BDL+Mel). Obstructive jaundice was induced by common bile duct ligation. Plasma level of nitric oxide (NO), total bilirubin (TB), direct bilirubin (DB), alanine aminotransferase (ALT), aspartate aminotransferase (AST), urea nitrogen (BUN) and creatinine (Cr) were measured 4 d and 8 d after operation. NO and inducible nitric oxide synthase (iNOS) in renal tissue were detected at the same time point, too. Histopathological changes of kidneys were examined by HE staining. ResultsIn BDL group, the plasma levels of NO, TB, DB, ALT, AST, BUN and Cr were higher than those of SO group (P＜0.01）, and the level of NO and activities of iNOS in renal tissue were significantly increased (P＜0.01）. However, in BDL+Mel group, the plasma levels of NO, ALT, AST, BUN and Cr were lower than those of the BDL group (P＜0.01）, and the level of NO and activities of iNOS in renal tissue were significantly suppressed (P＜0.01）; histopathological changes of kidneys were improved.ConclusionAugmentation of iNOS activities and increasing of NO production in local tissue contributed to renal injury induced by bile duct ligation, and the mode of melatonin’s protective actions, at least in part, relates to interference with no pathways.
【Abstract】Objective To investigate the expression of inducible nitric oxide synthase (iNOS) and p53 protein in hepatocellular carcinoma (HCC) and their relationship with angiogenesis. Methods Immunohistochemical method and image analysis technique were used to detect the expression of iNOS and p53 protein in tumor tissue sections of 59 HCC patients. Microvessel density (MVD) was counted by immunohistochemical staining with anti-CD34 antibody.Results ①The expression rates of iNOS and p53 were 81.4%(48/59), 64.4%(38/59) in HCC patients, respectively. The expression intensities of iNOS and p53 were 5 635±1 287, 3 352±873 in HCC patients, respectively. ②MVD was 32.5±2.73 in the tumor tissue of HCC patients. ③The expression of iNOS was correlated with the expression of p53 and MVD in HCC patients (P＜0.05); The expression of p53 was also correlated with the MVD in HCC patients (P＜0.05). Conclusion iNOS and p53 are highly expressed in HCC and may play a key role in angiogenesis of HCC.
Objective Observing the expressions of inducible nitric oxide synthase （iNOS） and endothelial nitric oxide synthase （eNOS） mRNA in lung tissues of rats with acute necrotizing pancreatitis （ANP） to explore the role of NOS in ANP associated-lung injury. Methods Forty Wistar rats were assigned into ANP group (n=30) and sham-operation group (SO group, n=10). ANP model was induced by retrograde injection of 5% sodium taurocholate into the bili-pancreatic duct. Pathological changes of the lung tissue were observed under light microscope at 3 h, 6 h and 12 h after the ANP-model operation, and the expressions of iNOS mRNA and eNOS mRNA in lung tissue were assayed by RT-PCR. Results Different degrees of pathological changes of the lung tissue, such as hyperemia, edema, inflammatory cells infiltration, hemorrhage and necrosis, were found in the ANP group. The pathologic injury scores of lung tissue in ANP group were higher than that in SO group (Plt;0.05), and gradually increased with the duration extension of ANP (Plt;0.05). Compared with the SO group, the expressions of iNOS and eNOS mRNA in ANP group were all higher at 3 h, 6 h, and 12 h (Plt;0.05). Conclusions The overexpressions of iNOS and eNOS mRNA may play important roles in lung injury of ANP. This provides us a theory basis that lung injury of ANP could be relieved by inhibiting the expressions of iNOS and eNOS mRNA.
Objective To study the effects of L-arginine （L-Arg） on cell proliferation, inducible nitric oxide synthase (iNOS) expression and cell cycle in human colon carcinoma cell line LS174 through nitric oxide (NO) pathway. Methods LS174 cells were cultured in medium with L-Arg at different concentrations for different times. MTT method was employed to evaluate the level of the cell proliferation. The production of NO in culture supernatants of LS174 cell was detected with enzyme reduction of nitrate. The distribution of the cell cycle was detected with the flow cytometry (FCM). The expression level of iNOS in the cells was determined by Western blot and SP immunocytochemical staining method. Results The growth of LS174 was promoted by the L-Arg at low concentration (0.125 mmol/L) and inhibited at high concentrations (0.5， 2， 8 and 32 mmol/L). The level of NO was increased with the increasing concentration of L-Arg in culture medium. To compare with the control group, the ratio of cells at S phase was increased after 48 hours’ treatments with high concentrations (0.5, 2, 8 and 32 mmol/L) of L-Arg (P＜0.05, P＜0.01); while there was no obvious difference after treatments with low concentration (0.125 mmol/L) of L-Arg (Pgt;0.05). With the increase of the concentration of L-Arg, the expression of iNOS was increased as compared with control group. The higher the concentration of L-Arg was, the better the effect. Conclusion L-Arg can induce the expression of iNOS resulting in increase the production of nitric oxide (NO). Low concentration of L-Arg can promote the growth of LS174 cells, while high concentration ones can inhibit growth and proliferation. The high concentration of L-Arg could induce S phase arrestion in the cell cycle.
Objective To investigate the effect of inducible nitric oxide synthase (iNOS) inhibitor aminoguanidine on pancreas islets cultured with cytokines TNF-α and IL-1β in rats. Methods Islets isolated from Wistar rats were purified and cultured. According to whether cytokines TNF-α, IL-1β and aminoguanidine were added into the medium respectively or not, islets were divided into 4 groups: cultured with islet only was taken as blank control group, cultured with TNF-α+IL-1β as cytokine group, cultured with aminoguanidine as aminoguanidine group, and cultured with TNF-α+IL-1β and aminoguanidine as aminoguanidine+cytokine group. NO level in culture medium and iNOS activity in islets tissue (Test Kit), apoptosis (TUNEL method) and viability of islets cell (acridine orange/ethidium bromide stain), and the function of islets (insulin release test) were measured. Results Compared with blank control group, the activity of iNOS in islet tissue and level of NO in culture medium increased, and the mass mortality and apoptosis appeared in islet cells, while insulin secretion decreased in cytokine group (P＜0.01). Compared with cytokine group, the activity of iNOS 〔（3.17±0.51） U/ml vs. （38.93±4.72） U/ml〕 and level of NO 〔（50.5±10.4） μmol/L vs. （313.0±35.4） μmol/L〕 decreased, the survival 〔（72.73±3.14）% vs. （57.07±5.07）%〕 increased and the apoptosis rate 〔（20.11±8.48）% vs. （41.17±6.87）%〕 decreased, the insulin secretion (secretion index: 3.50±0.27 vs. 1.96±0.19) improved； There were all significant differences in 2 groups (P＜0.01). Conclusion The iNOS inhibitor aminoguanidine could prevent the islet from the damage of iNOS/NO, alleviate the impairment of cytokines to islets, and ameliorate the survival and function of islets.
ObjectiveTo investigate the effect of Curcumin combined with Rhodiola on rats with severe acute pancreatitis (SAP) associated renal injury and explore the possible mechanisms. MethodsA total of 24 rats were randomly divided into SAP with renal injury group (SAP group, n=8), Curcumin group (n=8), Curcumin combined with Rhodiola group (n=8).The SAP group was given 1.5 mL saline through intragastric administration before operation while the Curcumin group was fed with same amount of Curcumin diluent.The Curcumin combined with Rhodiola group was given 1.5 mL Curcumin diluent through intragastric administration and 6 g/kg Rhodiola diluent through intraperitoneal injection before operation.The pancreas and pancreatic tail-segment was dissociated and the head of pancreas were occluded in rats to make the model, blood vessel forceps was loosed after three hours.All the rats were sacrificed at 18 h after modeling.The levels of serum amylase, creatinine, blood urea nitrogen were detected and pathological changes of pancreas and the left kidney were observed under the light microscope.The cell apoptosis was analyzed using TUNEL staining.The serum levels of interleukin (IL)-1β, IL-6, and IL-10 among the three groups were detected by enzyme-linked immunosorbent assay.The expression of inducible nitric oxide synthase (iNOS) mRNA in the right kidney was detected by real-time polymerase chain reaction.The superoxide dismutase (SOD) activity of the renal tissue was determined by hydroxylamine method. ResultsCompared with the SAP group, the levels of serum amylase, creatinine, blood urea nitrogen, IL-1β, IL-6, the cell apoptosis index, and the expression of iNOS mRNA were significantly decreased, the serum level of IL-10 and the activity of SOD were significantly increased (P < 0.05), the pancreas and the kidney damaged more slightly in the Curcumin group and Curcumin combined with Rhodiola group.Compared with the Curcumin group, the above situations were more better in the Curcumin combined with Rhodiola group. ConclusionsCurcumin combined with Rhodiola has a better protective effect on SAP associated renal injury.It might be through inhibiting the expressions of IL-1β, IL-6, stimulating the expression of IL-10, down-regulating the expression of iNOS mRNA, and improving the activity of SOD.It could reduce the cell apoptosis and necrosis of the kidney and improve the ability of the kidney to tolerate hypoxia.
ObjectiveTo investigate the effects of curcumin on expression of iNOS mRNA, study the protective and therapeutic effects on rats with severe acute panceratitis associated renal injury, and explore the possible mechanisms. MethodsA total of 24 rats were randomly divided into control group (n=8), severe acute panceratitis with renal injury group (injury group, n=8), and curcumin-treated group (treated group, n=8).The rats of control group and injury group were given 1.5 mL saline through intragastric administration at 3 h before operation, while the rats of treated group were fed with same amount of curcumin diluent at 3 h before operation.The rats of injury group and treated group with pancreatic head clamping method to establish the model of severe acute pancreatitis.At 12 h after modeling, rats in control group and injury group were perfused with 1.5 mL saline, and rats in treated group were intragastrically administrated to the same volume of curcumin diluent.All the rats were sacrificed at 18 h after modeling.The levels of serum amylase, creatinine, and blood urea nitrogen were detected and pathological chang of pancreas and the left kidney were observed under light microscope.The renal cell apoptosis were analyzed using TUNEL staining in three groups.The serum levels of interleukin-1β(IL-1β), interleukin-6 (IL-6), and interleukin-10 (IL-10) in three groups were detected by enzyme-linked immunosorbert assay (ELISA).The expressions of inducible nitric oxide synthase (iNOS) mRNA in the right kidney were detected with realtime polymerase chain reaction (RT-PCR) in three groups. ResultsCompared with the control group, the levels of serum amylase, creatinine, blood urea nitrogen, IL-1β, IL-6, and IL-10, the cell apoptosis and the expressions of iNOS mRNA in injury group and treated group were significantly increased (P < 0.05).In the treated group, the level of IL-10 was higher than the injury group (P < 0.05), and the difference of other indexes were lower than the injury group (P < 0.05). ConclusionsCurcumin has a better protective effect on severe acute pancreatitis associated renal injury.It may be through inhibited the expressions of IL-1βand IL-6, stimulated the expression of IL-10, and down-regulation of iNOS mRNA expression to reduce the generation of oxygen free radicals and NO damage to cell and reducing the cell apoptosis and necrosis of kidney.