1.Protection of Glycyl-L-Glutamine against myocardial ischemia-reperfusion injury in the isolated rat heart
Renbin QI ; Yi XIONG ; Daxiang LU ; Yanping WANG ; Yongmei FU
Chinese Journal of Pathophysiology 1989;0(05):-
AIM:To study the protection of Glycyl-L-Glutamine(Gly-Gln) against myocardial ischemia/reperfusion(I/R) injury in the isolated rat heart.METHODS:A model of myocardial ischemia-reperfusion injury was established with a Langendorff apparatus.Thirty male SD rats were randomly divided into four groups:control group,Gly-Gln group,I/R group and I/R+Gly-Gln group.Both I/R and I/R+Gly-Gln group were pre-perfused for 30 min,followed by 20 min ischemia and 40 min reperfusion.During reperfusion I/R+Gly-Gln group was perfused with Gly-Gln perfusate.Control group was kept perfused for 90 min.Gly-Gln group Gly-Gln perfusate was also kept perfused for 90 min.The left ventricular end-diastolic pressure(LVEDP),left ventricular developed pressure(LVDP),?dp/dtmax,heart rate(HR),monophasic action potentials(MAP) was measured during perfusion.The coronary effluent fluid was collected at different certain times.The activities of lactic dehydrogenase(LDH) and creatine kinase(CK) were determined.RESULTS:The isolated rat heart function decreased severely after 20 min ischemia and 40 min reperfusion(I/R):the LVEDP increased and the LVDP,?dp/dtmax decreased.But the LVEDP decreased and the LVDP,?dp/dtmax increased in I/R+Gly-Gln group compared with I/R group.Moreover,the activities of LDH and CK in the coronary effluent fluid decreased remarkably in I/R+Gly-Gln group compared with I/R group.CONCLUSION:Gly-Gln can play a protective role against myocardial I/R injury in isolated rat hearts via maintaining the left ventricular function and decreasing the release of LDH and CK.
2.Mechanisms underlying the protection of berberine against liver injury induced by lipopolysaccharide in mice
Meiai LI ; Huadong WANG ; Daxiang LU ; Yanping WANG ; Renbin QI
Chinese Journal of Pathophysiology 1989;0(05):-
AIM: To investigate the protective effects of berberine against liver injury induced by lipopolysaccharide in mice and the mechanisms underlying its protective effect.METHODS: The male mice were divided randomly into control,berberine group,LPS group and berberine treatment group.Mice were administered intragastrically with distilled water(0.01 mL/g) or(5 g/L) neutral sulfate berberine(0.01 mL/g) once a day for 5 days and injected intraperitoneally with normal saline or LPS(0.02(mL/g),28 mg/kg)at 1 h after gavage on day 5.Blood was collected for determining alanine aminotransferase(ALT) and aspartate aminotransferase(AST) activities,the content of tumor necrosis factors-?(TNF-?) at 10 h and 2 h after LPS or normal saline injection,respectively.Furthermore,the liver tissue was processed,and histological changes and ultrastructure in liver were observed with light and electron microscopy,malondialdehyde(MDA) content and superoxide dismutase(SOD) activity in liver were also detected.RESULTS: Both ALT and AST activities in serum in LPS group were higher than those in control and berberine treatment group.LPS increased the serum TNF-? content at 2 h after injection,which was reversed by berberine pretreatment.The histological examination showed that LPS caused severe hepatic cell edema,degeneration,apoptosis and even necrosis,and ultrastructure observation demonstrated that LPS induced mitochondrial swelling,condensation and margination of chromatin,irregular nuclear envelope in hepatocytes.The above pathological changes produced by LPS were attenuated by berberine pretreatment.Moreover,MDA contents in liver tissue were higher in LPS group than control and berberine treatment group,but there were no significant difference in SOD activity between berberine treatment and LPS group.CONCLUSION: Berberine has a protective effect on LPS-induced liver injury in mice,the mechanisms may be related to its decreasing the production of TNF-?,inhibiting lipid peroxidation and protecting mitochondria.
3.Effect of food intake on functional activities and biochemical index in mice
Qihao ZHANG ; Daxiang LU ; Yongmei FU ; Huadong WANG ; Renbin QI
Chinese Journal of Pathophysiology 1986;0(04):-
AIM: To study the effect of food intake on weight, memory, staying balance and power, and some biochemical indexes in mice. METHODS: In accordance with the average food intake everyday, the animals were divided into five groups: group A took the average food intake fully, group B took 75% of the average food intake, group C took 50% of the average food intake, group D took 25% of the average food intake, and group E did not take any food at all. The weights, memory, staying balance and power were recorded every three days, the biochemical index was recorded on the 10th day. RESULTS: On the 3rd day, the weight and staying balance and power of mice in group E decreased. On the 6th and 9th day, the weight of mice in group ABC increased. Compared with group B and C, the memory group A and D decreased. On the 10th day, the blood glucose concentratoin in of group D decreased, total cholesterol and triglyceride also decreased with the reduction of food intake. CONCLUSION: A food intake of 75%-50% in all helpes to keep a good body status and memory, decreases total cholesterol and triglyceride in blood.
4.Effects of several harmful factors on expression of glycine receptor α1 subunit in neonatal rat myocardial cells
Chutian CHEN ; Daxiang LU ; Renbin QI ; Huadong WANG
Chinese Journal of Pathophysiology 2015;(11):2005-2008
AIM:To study the expression of glycine receptorα1 subunit in neonatal rat myocardial cells and to investigate the effect of lipopolysaccharide (LPS), hypoxia/reoxygenation, isoproterenol (ISO) and high concentration of glucose (HG) on the expression of glycine receptorα1 subunit in the neonatal rat myocardial cells.METHODS:Neonatal rat myocardial cells were cultured in vitro.The expression of glycine receptorα1 subunit was detected by Western blotting. The neonatal rat myocardial cells were treated with LPS (20 mg/L), ISO (100 μmol/L) or high concentration of glucose (25 mmol/L) for 24 h, or were exposed to hypoxia for 3 h followed by reoxygenation for 3 h.Subsequently, the cell viabil-ity was measured by CCK-8 assay, and the expression of glycine receptorα1 subunit was determined by Western blotting. RESULTS:The expression of glycine receptor α1 subunit in the neonatal rat myocardial cells was positively detectable by Western blotting.Compared with control group, no significant difference of the cell viability ( P>0.05) in LPS group, ISO group, hypoxia/reoxygenation group and HG group was observed.The expression of glycine receptor α1 subunit was in-creased (P<0.01) in LPS group, ISO group and hypoxia/reoxygenatio group, but decreased (P<0.01) in HG group. CONCLUSION:Glycine receptorα1 subunit exists in the neonatal rat myocardial cells.A certain concentration of LPS or ISO, or hypoxia/reoxygenation for a certain period upregulate the expression of glycine receptorα1 subunit, but HG down-regulates the expression of glycine receptor α1 subunit in cultured neonatal rat myocardial cells.
5.Berberine inhibits enterocyte apoptosis in septic mice
Hongmei LI ; Yun XING ; Xiangxu TANG ; Duomeng YANG ; Huadong WANG ; Xiuxiu Lü ; Renbin QI ; Daxiang LU
Chinese Journal of Pathophysiology 2016;32(9):1660-1665
AIM: To observe the effects of berberine (Ber) on enterocyte apoptosis in septic mice and its pos-sible mechanism.METHODS: Male C57BL/6 mice (8 ~10 weeks old) were randomly divided into sham group, cecal ligation and puncture (CLP) group, CLP +Ber group and sham +Ber group.The mice in CLP group underwent CLP ope-ration, and the mice in sham groups suffered a similar operation except the ligation and puncture.After the sham or CLP operation, the mice were administered intragastrically with distilled water or berberine (50 mg/kg) within 2 h.After 20 h, the mice were killed with excess pentobarbital sodium and the ileum tissues were removed.The histological changes of the intestine were observed and the enterocyte apoptosis was examined by determining the protein level of cleaved caspase-3. Furthermore, mitochondrial Bax, cytoplasm cytochrome C (Cyt C) and the total proteins of Bcl-2, Fas, FasL and Fas-as-sociated protein with death domain (FADD) were examined by Western blot.The mRNA expression of tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DBH) was measured by real-time PCR.RESULTS: The extensive ileum injuries, including remarkably increased leukocytes and necrosis of intestinal villus were observed 20 h after CLP.In CLP group, the protein levels of cleaved caspase-3, cytoplasm Cyt C, as well as Fas, FasL were significantly increased, but the Bcl-2 level was decreased.Bax translocation into mitochondria was promoted.However, FADD was not changed significantly.The mRNA expression of TH and DBH was also increased sharply in CLP group.On the contrary, treatment with berberine made a considerable alleviating alteration in the ileum of the septic mice.CONCLUSION: Treatment with berberine pro-vides protective effects on intestinal injury in septic mice by reducing enterocyte apoptosis, and its possible mechanism may be involved in the inhibition of the endogenous and exogenous apoptosis pathways.
6.Effect of Glycine on endotoxin induce myocardial cell injury of isolated rat heart
Renbin QI ; Daxiang LU ; Huadong WANG ; Hua ZHOU ; Haihua WANG ; Chujie LI
Chinese Pharmacological Bulletin 1986;0(06):-
Aim To observe the protective effect of glycine from myocardial cell injury of the isolated rat heart induced by endotoxin. Methods 21 male SD rats,weghting(250?30)g,were randomly divided into three groups:control group(n=7),endotoxin group(n=7),glycine/endotoxin group(n=7).Heart were isolated from the rats and perfused on Langendorff apparatus with Krebs-Henseleit(KH)buffer(Saturation 95%+5% CO_2)at a constant pressure(8.33 kPa)and temperture(37℃). The activities of lactate dehydrogenase(LDH),creatine kinase(CK),superoxide dismutase(SOD) and the level of malondialdehyde (MDA) of efflux from coronary artery, monophasic action potential(MAP)were determined at the certain time(0,20,50,80 min). Results Monophasic action potential were markedly improved in Gly/ET group. Glycine can attenuate the release of LDH,CK from myocardial cell. The activity of SOD and the level of MDA were close to control group. Conclusion Glycine can protect myocardial cells of the isolated rat heart from the damage induced by endotoxin.
7.Protection of maFGF against anoxia/reperfusion injury in isolated rat hearts
Yan LI ; Jing LI ; Xiaokun LI ; Daxiang LU ; Renbin QI ; Ying GUAN ; Yongmei FU
Chinese Journal of Pathophysiology 1989;0(05):-
AIM: To investigate the protective effects and mechanisms of modified acidic fibroblast growth factor (maFGF) in anoxic reperfusion of rat hearts. METHODS: Using Langendorff apparatus, we established the model of anoxia/reperfusion of isolated hearts to compare the protective effects of maFGF and acidic fibroblast growth factor (aFGF). The changes of left ventricle development pressure (LVDP) and maximal rates of rise of ventricular pressure(dp/dt_~max ), maximal rates of decline of ventricular pressure (dp/dt_~min ) were determined, changes of LDH and MDA levels,SOD activity in efflux from coronary artery were also detected at different time point. RESULTS: Pretreatment with maFGF and aFGF produced a similar protective effect on myocardium during anoxia /reperfusion, including promoting obviously heart functional recovery after myocardial anoxia/reperfusion and reversing changes of LDH, MDA contents and SOD activity induced by anoxic/reperfusion. CONCLUSION: maFGF has a protective effect on anoxia/reperfusion heart, and the mechanism of this effect may be related to suppression of lipid peroxidation.
8.Effect of glycine on body weight and lipid metabolism in mice
Jing LIU ; Daxiang LU ; Huadong WANG ; Renbin QI ; Yongmei FU ; Yanping WANG
Chinese Journal of Pathophysiology 1989;0(06):-
AIM: To study the effect of glycine on body weight and lipid metabolism in mice. METHODS: Mice were randomly divided into four groups, control, high-fat diet group (HF), glycine group (Gly), and glycine treatment group (Gly+HF). The mice were fed with normal diet and high-fat diet for 12 days, respectively, and then were treated with glycine solution by intraperitoneal injection. Finally, the serum was collected to measure serum lipid, epididymal fat-pads, pararenal fat-pads and abdominal fat-pads were taken out to weight. Moreover, pathologic changes in liver were observed. RESULTS: The body weight of HF group was obviously lower than that in control; the body weight and adipose tissue content of Gly group were obviously lower than those in control; the body weight and adipose tissue content of Gly+HF group were obviously lower than those in HF group; the levels of TC and TG in Gly group were obviously lower than those in control; there was no statistical difference in serum lipid between Gly+HF and HF groups. In addition, marked hepatic steatosis in HF group, and slight hepatic steatosis in Gly+HF group were found. CONCLUSION: Gly can decrease the body weight and adipose tissue content and serum lipid in normal diet and high-fat diet mice, and it also can prevent hepatic steatosis.
9.Harmful factors affect glycine receptor ?_1 subunit mRNA expression in the neonatal rat cardiomyocytes
Chutian CHEN ; Daxiang LU ; Renbin QI ; Huadong WANG ; Yongmei FU ; Yanping WANG
Chinese Journal of Pathophysiology 1989;0(05):-
0.05).The expression of glycine receptor ?1 subunit mRNA was increased(P
10.Preliminary mechanism of senegenin against H/R-induced apoptosis of primary cortical neurons
Yandong ZHAO ; Panhong LIU ; Xuemin LI ; Fan LU ; Huadong WANG ; Daxiang LU ; Renbin QI
Chinese Journal of Pathophysiology 2014;(7):1166-1171
AIM:To explore the preliminary mechanism of senegenin ( Sen) on inhibiting hypoxia/reoxygenation ( H/R)-induced apoptosis of primary cortical neurons .METHODS:The cultured cortical neurons were randomly divided in-to normal group (control group), model group (H/R group), Sen+H/R group and Sen group.Flow cytometry was used to evaluate the effect of Sen on H/R-induced cell apoptosis .The protein levels of JNK , p-JNK, c-Jun, p-c-Jun, Bcl-2 and Bax were assessed by Western blotting .RESULTS:The apoptotic rate in H/R group was obviously higher than that in control group (P<0.05), while the apoptotic rate in Sen +H/R group was obviously lower than that in H/R group (P<0.05), suggesting that the model of apoptosis was established successfully .The results of Western blotting showed that Sen increased the expression of JNK and c-Jun, inhibited the phosphorylation of JNK and c-Jun (P<0.05), increased the protein level of Bcl-2 and inhibited the protein level of Bax in H/R treated primary cortical neurons (P<0.05).CONCLUSION:Sen has a protective effect against H/R-induced neuronal apoptosis by increasing the expression of JNK and c-Jun, inhibiting the phosphorylation of JNK and c-Jun, increasing the protein level of Bcl-2 and decreasing the protein level of Bax .