Effects of metformin combined with Ge Xia Zhu Yu decoction on TLR4/NF-κB signaling pathway in rats with polycystic ovary and insulin resis-tance

AIM: To study the effect of metformin (Met) combinated with Ge Xia Zhu Yu decoction on Toll-like receptor-4 (TLR-4)/nuclear factor-κB (NF-κB) signaling pathway in the rats with polycystic ovary syndrome (PCOS) and insulin resistance induced by dehydroepiandrosterone, and to explore the mechanisms. METHODS: PCOS rats (after induced by dehydroepiandrosterone, n=110) were randomly divided into 3 groups:model group (30 rats), Met treatment group (40 rats) and Met combinated with Ge Xia Zhu Yu decoction treatment (combination) group (40 rats). The rats in model group were given the same volume of 0.9% sodium chloride daily by gavage. The rats in Met group were given Met (270 mg·kg^-1·d^-1) by gavage. The rats in combination group were given Met (270 mg·kg^-1·d^-1) and Ge Xia Zhu Yu decoction (34.5 mg·kg^-1·d^-1) by gavage. All rats were continuously intervened for 28 d. After the intervention, blood glucose[fasting plasma glucose (FPG) and 2-hour postprandial blood glucose (2hPBG)] was measured. The mRNA expression levels of follicular epithelial NF-κB, TLR-4 and oxidized low-density lipoprotein (ox-LDL) were detected by RT-PCR. The serum levels of inflammatory cytokines interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and C-reactive protein (CRP) were also detected by ELISA. RESULTS: After the intervention, FPG, 2hPBG, and serum levels of IL-6, TNF-α and CRP in Met group and combination group were lower than those in model group (P<0.05), and those in combination group were lower than those in Met group (P<0.05). Meanwhile, the mRNA expression levels of follicular epithelial NF-κB, TLR-4 and ox-LDL in Met group and combination group were lower than those in model group (P<0.05), and those in combination group were lower than those in Met group (P<0.05). CONCLUSION: Treatment with Met combined with Ge Xia Zhu Yu decoction improves insulin resistance in PCOS rats by decreasing the levels of inflammatory factors in serum and epithelial cells of ovary and inhibiting the expression of NF-κB, TLR-4 and ox-LDL in epithelial tissue of ovary.     

Effect of QHBJ decoction on ovarian cancer in female rats by dimethylphenyl allium

AIM: To investigate the effects of Qinghao-Biejia (QHBJ) decoction on ovarian cancer in female rats by dimethylphenyl allium. METHODS: Ovarian cancer female rat model was established by embedding medicine thread with dimethylphenyl allium in situ. After successful modeling, the rats were divided into model group with the same volume of normal saline, high dose group with QHBJ decoction at 3 g·kg^-1·d^-1, medium dose group with QHBJ decoction at 1.5 g·kg^-1·d^-1, low dose group with QHBJ decoction at 0.75 g·kg^-1·d^-1 and western medicine group with meloxicam at 4 mg·kg^-1·d^-1. After 6 weeks of administration, the tumor weight and tumor inhibition rate of ovartian tumor were measured.Expression of Bcl-2 and Bax proteins were detected by immunohistochemistry. The protein levels of AKT, p-AKT and BTAK were determined by Western blot. RESULTS: QHBJ decoction decreased the protein levels of Bcl-2, AKT, p-AKT and BTAK, increased the protein level of Bax,and reduced the tumor weight of ovarian tumor. The anti-tumor rate of ovarian tumors in each group showed a significant increase in a dose-dependent manner with QHBJ decoction (F=34.2, P=0.000 5). CONCLUSION: QHBJ decoction inhibits the proliferation of ovarian cancer cells induced by dimethylphenyl allium by regulating the balance of Bcl-2 protein and Bax protein, decreasing the protein levels of AKT, p-AKT and BTAK.     

Effect of methylene blue on T-lymphocyte subsets and oxidative stress in rat thymus with paraquat poisoning

AIM: To illustrate the effect of methylene blue(MB) on T-lymphocyte subsets and oxidative stress of the thymus in rats with paraquat(PQ) poisoning.METHODS: Male SD rats(n=40) were randomly assigned to 4 groups: normal group, control group, low-dose(2 mg·kg^-1·d^-1) MB group and high-dose(4 mg·kg^-1·d^-1) MB group. After 72 h, the pathological morphological changes of the thymus were observed under microscope with HE staining. The SOD activity and MDA content were measured by colorimetry method. The expression of Bcl-2, Bax, CD4 and CD8 was determined by immunohistochemical method.RESULTS: In MB group, the thymus tissue showed good corticomedullary demarcation. MDA content decreased and SOD activity increased, indicating that the ability of antioxidation enhanced. Bcl-2 and Bax expression was down-regulated, Bcl-2/Bax ratio increased, and CD4 positive cells increased.CONCLUSION: MB protects against oxidative damage induced by PQ, and regulates the distribution of T-lymphocyte subsets in the cortex and medulla, thus relieving the persistent body damage.     

Renoprotective effect of L-carnitine on streptozotocin-induced diabetic nephropathy in rats

AIM: To investigate whether L-carnitine (LC) treatment confers renoprotection in a rat model of streptozotocin (STZ)-induced diabetic nephropathy (DN). METHODS: Diabetic animal model was established by intraperitoneal injection of STZ (65 mg/kg) in Sprague-Dawley rats. Diabetic rats were treated with LC (50 mg·kg^-1·d^-1 or 200 mg·kg^-1·d^-1 intravenously) daily for 12 weeks. The effects of LC on STZ-induced DN were evaluated by assessing renal function, urinary protein excretion, histopathological changes, macrophage infiltration, the expression of proinflammatory and prosclerotic cytokines, and the expression of nuclear factor-κB (NF-κB) and apoptosis-related gene. RESULTS: LC administration significantly decreased glomerulosclerosis, preserved the number of podocytes, and reduced macrophage infiltration. These changes were accompanied by improvements in urinary protein excretion and renal dysfunction. LC treatment suppressed the expression of proinflammatory and prosclerotic cytokines, and these changes were paralleled by significant attenuation of NF-κB and apoptosis-related gene expression. CONCLUSION: LC has a renoprotective effect against STZ-induced DN in rats.     

Effects of grape seed procyanidin on vascular remodeling in renovascular hypertensive rats

AIM: To study the effect of grape seed procyanidin (GSP) on vascular remodeling in renovascular hypertensive (RH) rats. METHODS: The RH rat model was established by two-kidney one-clip method. Two weeks after operation, 28 rats were selected according to the increased tail systolic pressure above 130 mmHg and randomly divided into 4 groups (n=7): RH model group, low GSP treatment group (50 mg·kg^-1·d^-1),high GSP treatment group (200 mg·kg^-1·d^-1) and captopril treatment group (30 mg·kg^-1·d^-1). Meanwhile, 7 rats with sham operation served as controls. Tail systolic pressure, medial thickness (MT), luminal diameter (LD), and the ratio of MT to LD in thoracic aortic wall were determined 6 weeks after treatment. Masson staining and ELISA were used to detect the content of collagen and angiotensin II (Ang II) in aortic tissues. The protein expression of tumor necrosis factor α (TNF-α) in abdominal aortic tissues was determined by Western blotting. RESULTS: Compared with control group, the tail systolic pressure, MT, MT/LD, the content of collagen and the protein expression of TNF-α in aorta were significantly increased in RH model group, but LD decreased. Treatment with GSP and captopril reduced the raised parameters, and increased the LD in RH model rats. These effects were more notable in high GSP treatment group, and equal to captopril treatment group. CONCLUSION: GSP treatment significantly decreases tail systolic pressure in RH rats, and effectively attenuates arterial vascular remodeling by decreasing the content of AngII and reducing the protein expression of TNF-α in aorta.     

Interventional effects of tongxinluo combined with atorvastatin and aspirin on adventitial inflammation in early stage of atherosclerosis

AIM: To investigate the effect of a treatment proposal, which consisted of tongxinluo, atorvastatin and aspirin, on adventitial inflammation of early atherosclerosis in rabbit carotid artery. METHODS: The atherosclerotic model was established in the rabbits with silicone collar, which was positioned around the carotid arterial adventitia+high-cholesterol diet. New Zealand rabbits (n=72) were randomly divided into 6 groups (n=12): control group, model group, tongxinluo group, atorvastatin group, aspirin group, and three-drug combination group. The rabbits in control group were fed with common foodstuffs, and the rabbits in all the other groups were fixed the right carotid arteries with the silicone tube, and were fed with fatty foodstuffs. The rabbits in tongxinluo group, atorvastatin group and aspirin group were given the suspension of tongxinluo supermicropowder (0.3 g·kg^-1·d^-1), atorvastatin (2.5 mg·kg^-1·d^-1) and aspirin (12 mg·kg^-1·d^-1) respectively,and the rabbits in three-drug combination group were given the suspension of tongxinluo supermicropowder (0.3 g·kg^-1·d^-1), atorvastatin (2.5 mg·kg^-1·d^-1) and aspirin (12 mg·kg^-1·d^-1) together. The rabbits in each group were fed with the corresponding medicines for 4 weeks. The tissue slices of carotid artery were observed under light microscope with HE staining. The change of blood lipid was detected by biochemical assay. The protein levels of MCP-1, IL-1β and IL-10 in the carotid arterial adventitia were detected by ELISA. The immunohistochemical staining was used to detect the protein expression of IL-8 around the carotid arterial adventitia.RESULTS: Compared with control group, the contents of TC, TG and LDL-C were significantly increased, and the content of IL-10 was significantly decreased in model group. The levels of TC, TG and LDL-C were significantly decreased in tongxinluo group and atorvastatin group compared with model group, no significant difference between tongxinluo group and atorvastatin group was observed. In the three-drug combination group, the levels of TC, TG and LDL-C were lower than those in atorvastatin group and tongxinluo group. Compared with control group, the contents of MCP-1 and IL-1β were significantly increased, and the content of IL-10 was significantly decreased in model group. Compared with model group, the contents of MCP-1 and IL-1β were decreased in tongxinluo group, atorvastatin group and aspirin group, no significant difference between the 3 groups was observed. The content of IL-10 was decreased in three-drug combination group, and the contents of TC, TG and LDL-C were lower than those in tongxinluo group, atorvastatin group and aspirin group. The content of IL-8 was decreased in tongxinluo group, atorvastatin group, aspirin group and three-drug combination group.CONCLUSION: The strategy of three-drug combination enhances the effect of regulating the lipid metabolism and inhibiting the adventitia inflammation. It plays an important role to intervene in the process of atherosclerosis.     

Effects of valsartan alone or in combination with benazepril on blood pressure and left ventricular hypertrophy in spontaneously hypertensive rats

AIM:To evaluate the effects of different doses of valsartan alone or with concomitant be-nazepril on blood pressure,left ventricular hypertrophy,RAASfunction and endoxi nlevel in spontaneously hy-pertensive rats(SHR).METHODS:Thirty SHR(fourteen-week-old,male)were divi ded into five groups(six rats in each group):SHR control group:fed with normal saline;benazepril group:fed with 1 mg·kg^-1·d^-1benazepril);low dose valsartan group:fed with 8 mg·kg^-1·d^-1valsartan;high dose valsartan group:fed with 24 mg·kg^-1·d^-1valsartan;combination drug therapy group:fed with valsartan(8 mg·kg^-1·d^-1)and benazepril(1 mg·kg^-1·d^-1),all for 8 weeks.WKY control group(n=6):fed with normal saline for 8 weeks.RESULTS:SBP,LVM/BW,TDMof SHR were remarkably lower than those of control after drug i n-tervene,and effect on SBP was most remarkable in high dose valsartan group and i nthe combi nation drug ther-apy group;effect on LVM/BW,TDM were most remarkable in combination drug therapy group.Renin activi-ties in plasma and myocardiumwere remarkably i ncreased in drug i ntervene groups.The levels of AngⅡi nplasma and myocardiumwere remarkably increased in two different dose of valsartan treati ng group,and thelarger dose of valsartan were,the higher levels of AngⅡin plasma and myocardium were;decreased in be-nazepril treati ng group and combination drug therapy group.Na⁺-K⁺-ATPase activities in myocardi umwere remarkably i ncreased and the level of endoxi n i n myocardium were remarkably decreased as SBP de-creased after drug intervene.CONCLUSION:Different dose of valsartan alone or combi ned with benazeprilcan decrease SBP of SHR,have the effect of inhibiti ng progression of ventricular hypertrophy.The effect ofcombination drug therapy group was most remarkable among five groups and can avoi d the si de effect of highAngⅡin plasma and myocardiumduri ng long-termuse of valsartan alone.     

Effect of salvianolic acid B on vasodilatory function,NF-κB activation and inflammatory cytokine expression in diabetic rats

AIM: To investigate the ameliorative effect of salvianolic acid B on vasodilatory function in diabetic rats and the possible mechanisms. METHODS: SD rats (n=40) were fed on high-sugar and high-fat diet for 4 weeks, followed by a single intraperitoneal injection of streptozotocin (40 mg/kg). The rats with random blood glucose level over 16.7 mmol/L were considered diabetic and randomly allocated to 3 groups, namely model group, low dose (80 mg·kg^-1·d^-1) of salvianolic acid B group and high dose (160 mg·kg^-1·d^-1) of salvianolic acid B group. The rats in salvianolic acid B groups were intragastrically administered with corresponding doses of salvianolic acid B for 6 weeks. Vasodilatory function was measured as endothelium-dependent and-independent vasodilation of the aortic rings. The primary histopathological changes of aorta were observed by HE staining. Serum levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and C-reactive protein (CRP) were measured by ELISA. The levels of total antioxidant capacity, malondialdehyde (MDA) and nitric oxide (NO) in aortic tissues were evaluated by colorimetric assays. The protein levels of intercellular adhesion molecule-1 (ICAM-1) and monocyte chemotactic protein-1 (MCP-1), and the activation of nuclear factor-κB (NF-κB) were determined by Western blot. RESULTS: Treatment with salvianolic acid B evidently ameliorated endothelium-dependent diastolic function and pathological changes of aorta in diabetic rats (P<0.05 or P<0.01). Supplementation with salvianolic acid B resulted in significant increases in NO content and total antioxidant capacity in aortic tissues, accompanied by marked decreases in the level of MDA in aorta tissues and the serum levels of IL-6, TNF-α and CRP (P<0.05 or P<0.01). Salvianolic acid B markedly down-regulated NF-κB p65 nuclear translocation and protein expression of ICAM-1 and MCP-1 in aorta tissues (P<0.05 or P<0.01). CONCLUSION: Salvianolic acid B effectively ameliorates endothelium-dependent diastolic function of aorta in diabetic rats, which might be attributed to suppression of NF-κB activation and subsequent expression of inflammatory cytokines. The beneficial effect of salvianolic acid B on vascular endothelium might be derived from its antioxidant capacity.     

Effect of chelerythrine on TGF-β/Smads signaling pathway in mouse livers with hepatic fibrosis

AIM:To investigate the anti-hepatic fibrosis effect of chelerythrine on mice and the regulation of transforming growth factor-β (TGF-β)/Smads signaling pathway. METHODS:C57BL/6N mice (n=50) were randomly divided into control group, model group and chelerythrine groups (10 mg·kg^-1·d^-1, 20 mg·kg^-1·d^-1 and 40 mg·kg^-1·d^-1, ig). The mouse model of hepatic fibrosis was established by intraperitoneal injection of carbon tetrachloride (CCl₄) in combination with the olive oil for 8 weeks. At the 5th week, different doses of chelerythrine was used to treat hepatic fibrosis in the mice. At the 14th week, hepatic index was detected. Histopathological changes and the degree of hepatic fibrosis were observed by hematoxylin-eosin staining and Van Gieson staining. The serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and hyaluronic acid (HA), and hepatic hydroxyproline (Hyp) content were assayed by spectrophotometry and ELISA. The mRNA expression of TGF-β₁, Smad3, Smad4 and Smad7 in the liver was detected by RT-qPCR, and the protein expression of TGF-β₁, Smad4 and Smad7 was determined by Western blot. RESULTS:The degree of hepatic fibrosis changed markedly in model group compared with control group. The hepatic index, the serum levels of ALT and AST, and the contents of HA and Hyp were significantly increased (P<0.05). The mRNA expression of TGF-β₁, Smad3 and Smad4 was significantly up-regulated, while the mRNA expression of Smad7 was significantly down-regulated (P<0.05). The protein expression of TGF-β₁ and Smad4 was significantly up-regulated, while the protein expression of Smad7 was significantly down-regulated (P<0.05). Compared with model group, the changes of the above indexes in chelerythrine groups were inhibited. CONCLUSION:Chelerythrine protects the mouse liver from CCl₄-induced fibrogenesis injury by regulating TGF-β/Smads signaling pathway.     

Effect of rhynchophylline on TGF-β1/Smad pathway for processing ventricular remodeling in spontaneously hypertensive rats

AIM: To investigate the effect of rhynchophylline (Rhy) on blood pressure, cardiac hypertrophy and myocardial fibrosis in spontaneously hypertensive rats (SHR). METHODS: Spontaneously hypertensive rats were randomly divided into model group, high dose (10 mg·kg^-1·d^-1) and low dose (2.5 mg·kg^-1·d^-1) group of rhynchophylline, captopril group (17.5 mg·kg^-1·d^-1). Wistar-Kyoto rats were used as normal control. Respectively, systolic blood pressure was measured by tail cuff every 2 weeks. After 10 weeks, heart weight index and left ventricular weight index were calculated. The myocardial hydroxyproline and plasma angiotensin Ⅱ were detected. Moreover, basic myocardial histopathological changes and myocardial collagen fibres were observed by HE staining and Masson staining, respectively. The protein expression of TGF-β₁ and Smad3 in the myocardium was measured by the methods of immunohistochemistry and Western blot. RESULTS: Compared with SHR model group, Rhy significantly reduced blood pressure (P<0.05), the levels of HYP in the myocardium (P<0.05) and the levels of AngⅡ in the plasma (P<0.01). The pathological damages of the myocardial tissues and collagen deposition were attenuated. The protein expression of TGF-β₁ and Smad3 was significantly reduced by the treatment with Rhy (P<0.01). CONCLUSION: Rhynchophylline reduces blood pressure and adjusts to improve ventricular remodeling of SHR. The mechanism may be involved in the TGF-β₁/Smad pathway and reducing AngⅡ content.     

Effects of butylphthalide on atherosclerosis lesion and VCAM-1 expression in aortic wall of ApoE-/- mice

AIM: To observe the protective effects of butylphthalide on atherosclerosis lesion and vascular cell adhesion molecular-1 (VCAM-1) expression in the aortic wall of ApoE^-/- mice, and to explore the possible mechanism underlying these beneficial effects.METHODS: Male ApoE^-/- mice at 6 weeks of age (n=90) were randomly divided into 3 groups. Thirty ApoE^-/- mice fed with high-fat diet and treated with saline simultaneously were defined as model group. Thirty ApoE^-/- mice fed with high-fat diet and treated with butylphthalide (100 and 200 mg·kg^-1·d^-1) were defined as treatment groups. Thirty wild-type C57BL/6J mice treated with saline were defined as control group. Fifteen mice in each group were sacrificed both at the ages of 18 and 30 weeks. The body weight, food intake and water intake were monitored weekly through the experiment. The lipid profiles were determined both at 18 and 30 weeks of age. Aortic roots were stained with hematoxylin and eosin for pathological examination. Serum ox-LDL, CRP, TNF-α and IL-6 were examined by ELISA. The expression of VCAM-1 at mRNA and protein levels was determinate by real-time PCR and Western blot in the thoracic aortas. RESULTS: Compared with control group, at 18 and 30 weeks of age, the body weight, serum lipid profiles and inflammatory factors were increased, while the atherosclerotic plaques were raised. The mRNA and protein levels of VCAM-1 were up-regulated. However, serum lipid levels in butylphthalide treatment groups (both at doses of 100 and 200 mg·kg^-1·d^-1) were decreased significantly. Serum ox-LDL, CRP, TNF-α and IL-6 were also decreased by butylphthalide treatment. Furthermore, atherosclerotic plaque areas in the aortic roots were reduced by butylphthalide treatment. In addition, the expression of VCAM-1 at mRNA and protein levels in the thoracic aortas was down-regulated by butylphthalide treatment.CONCLUSION: Butylphthalide delays the occurrence of high-fat diet-induced atherosclerosis and down-regulates the expression of VCAM-1 in the ApoE^-/- mice, which may be due to its alleviative effects on hyperlipidemia and inflammation.     

Experimental study on pathogenesis of salt-induced hypertension

AIM:To reveal the pathogenesis of salt-induced hypertension.METHODS:Forty male SD rats were divided into five groups, which received on same chow but different drink. Control(NC)group: deionized water; High salt(HS)group: 1.5% NaCl solution; L-arginine(HS+Arg)group: L-arginine(4 g·kg^-1·d^-1)in 1.5% NaCl solution; Enalapril (HS+En) group: enalapril (30 mg·kg^-1·d^-1) in 1.5% NaCl solution; Terazozin(HS+Ter)group: terazozin(4 mg·kg^-1·d^-1)in 1.5% NaCl solution. At the end of 8 weeks, rats were anesthetized with pentobarbital sodium. Blood pressure(BP)were recorded and blood were drawn from inferior vena cava and kidneys, adrenals were removed. NO(x),ET and AngII, Na^＋-K^＋-ATPase and proscillaridin-like compound(PLC)were assayed.RESULTS:BP, PLC and ET in plasma and AngII in adrenal were increased, NO(x)and AngII in plasma and kidney were decreased in HS group compared with NC group.CONCLUSION:High salt intake may induce hypertension in SD rats. In addition to the Na^＋-K^＋-ATPase activity was inhibited by increased sodium-pump inhibitors, NO release decrease may also play an important role in the pathogenesis of hypertension.     

Effect of rosuvastatin combined with irbesartan on remodeling of myocardial hypertrophy in rats

AIM: To evaluate the effect of rosuvastatin combined with irbesartan on the remodeling of myocardial hypertrophy in the rats. METHODS: Male SD rats(n=50) were randomly divided into control group, model group, rosuvastatin group, irbesartan group and combination group. The model of myocardial hypertrophy was established by subcutaneous injection of isoproterenol at dose of 2.5 mg/kg for 14 d. From the first day of modeling, the rats in control group and model group received intragastrical saline, and the rats in rosuvastatin group, irbesartan group and combination group were treated with rosuvastatin(4 mg·kg^-1·d^-1), irbesartan(15 mg·kg^-1·d^-1) and rosuvastatin(4 mg·kg^-1·d^-1)+ irbesartan(15 mg·kg^-1·d^-1), respectively. The interventions continued for 4 weeks. After the interventions, the cardiac mass index and left ventricular mass index of the SD rats were measured. Besides, the degree of myocardial hypertrophy was observed with HE staining. The mRNA expression of hypertrophy-related factors, such as ANF, β-MHC and AT1R was determined by RT-PCR, and the protein expression of AT1R was determined by Western blot. RESULTS: Compared with control group, the cardiac mass index, left ventricular mass index, as well as the mRNA expression of ANF and β-MHC in model group were significantly increased(P<0.05). Compared with model group, the above factors in rosuvastatin group and irbesartan group were decreased(P<0.05), and the factors in combination group were lower than those in rosuvastatin group and irbesartan group(P<0.05). In addition, the expression of AT1R at mRNA and protein levels in rosuvastatin group and irbesartan group was lower than that in model group(P<0.05), while the expression AT1R at mRNA and protein levels in combination group was lower than that in rosuvastatin group and irbesartan group(P<0.05). CONCLUSION: Rosuvastatin and irbesartan are equally effective drugs to resist the formation of myocardial hypertrophy by decreasing the expression of AT1R. Moreover, combination of the 2 drugs is more effective to improve the degree of myocardial hypertrophy than the 2 drugs alone.     

Rebamipide repairs injury of small intestinal epithelial barrier induced by aspirin in mice

AIM: To investigate whether rebamipide repairs the small intestinal epithelial barrier in aspirin-induced small intestinal injury (SⅡ) in mice and its mechanism.METHODS: Small intestinal injury was induced by aspirin (200 mg·kg^-1·d^-1 for 5 d) in BALB/c mice. Based on the treatment with aspirin and/or rebamipide (320 mg·kg^-1·d^-1), the mice were divided into 4 groups (n=18 in each group). The living mice in each group (n=6) were sacrificed via cervical dislocation method at day 0, day 5, and day 10. The structure and function of intestinal barrier and the levels of the signaling pathway factors were measured by transmission electron microscopy, immunohistochemistry, qPCR, and Western blot.RESULTS: Tight junctions between intestinal epithelial cells improved significantly after reba-mipide treatment. The expression of ZO-1 and occludin in the injured small intestine showed a gradually increasing trend after rebamipide administration (P<0.05). There was a decreased trend of D-lactate level in rebamipide-treated SⅡ mice (P<0.05). The expression of cyolooxygenase-2 (COX-2), β-catenin, and c-Myc, and prostaglandin E₂ concentration in small intestinal tissues were significantly increased in rebamipide treatment group (P<0.05). However, down-regulated COX-1 expression in the SⅡ mice was sustained at a low level after rebamipide administration.CONCLUSION: Rebami-pide repairs the injury of small intestinal mucosa and improves the structure and function of small intestinal barrier in aspirin-induced SⅡ mice by up-regulating the expression of COX-2.     

Effect of leonurine on expression of miR-1 in rats with myocardial fibrosis induced by isoproterenol

AIM: To investigate effect of leonurine on the expression of microRNA-1 (miR-1) in rats with myocardial fibrosis induced by isoproterenol (ISO). METHODS: SD rats (n=10) were used as normal control group, and 80 rats were given ISO by intraperitoneal injection daily for 2 weeks to establish the model of myocardial fibrosis. The model rats were randomly divided into 5 groups:model group, low-dose (7.5 mg·kg^-1·d^-1) leonurine group, middle-dose (15 mg·kg^-1·d^-1) leonurine group, high-dose (30 mg·kg^-1·d^-1) leonurine group and p38 mitogen-activated protein kinase (p38 MAPK) inhibitor (0.3 mg·kg^-1·d^-1) group. After the treatment for 2 weeks, the ultrastructure of left ventricular myocardial tissues was observed under electron microscope. Masson staining was used to detect collagen fibrosis, and the expression of collagen I and collagen Ⅲ was determined by the method of immunohistochemistry. The contents of endothelin-1 (ET-1) and angiotensin Ⅱ (Ang Ⅱ) were measured by ELISA. The expression of miR-1 and ET-1 mRNA was detected by real-time PCR, and the protein expression of p38 MAPK, β-myosin heavy chain (MHC) and α-MHC was determined by Western blot. RESULTS: Compared with model group, the ultrastructure of left ventricular myocardial tissues in high-dose leonurine group was attenuated, and the expression of miR-1 and the protein expression of α-MHC in left ventricular myocardial tissues of high-dose leonurine group were increased (P<0.05). Collagen volume fraction, collagen I, collagen Ⅲ, the ratio of collagen Ⅰ/collagen Ⅲ, the contents of ET-1 and Ang Ⅱ, the mRNA expression of ET-1, and the protein expression of p38 MAPK and β-MHC in high-dose leonurine group were lower than those in model group (P<0.05). CONCLUSION: Leonurine attenuates myocardial fibrosis in the rats induced by ISO, and it is potentially associated with affecting the expression of miR-1, and inhibiting ET-1/p38 MAPK signaling pathway.     

Role of bradykinin in the therapeutic effect of enalapril on left ventricular hypertrophy and cardiac function after myocardial infarction in rats

AIM:To investigate the influences of bradykinin(BK)on left ventricular hypertrophy and cardiac function in angiotensin-converting enzyme inhibitor(ACEI) therapy in rats after myocardial infarction.METHODS:The effects of enalapril (500 μg·kg^-1·d^-1), enalapril (500 μg·kg^-1·d^-1)with BKB₂ receptor antagonist (Hoe-140 500 μg·kg^-1·d^-1), losartan(3 mg·kg^-1·d^-1) on left ventricular end-diastolic pressure (LVEDP), maximum positive left ventricular pressure change (+dp/dt_max) and LVW/BW as well as V(m)n of noinfarcted area were examined after 4 weeks treatment in rats after myocardial infarction.RESULTS:The values of LVEDP, LVW/BW and V(m)n of three treatment groups were higher than that of untreated MI group (P＜0.05),but the +dp/dt_max of three treatment groups were not significantly different compared with the untreated MI group. In addition, no significant difference in MAP was observed among the three treatment groups, but the LVW/BW and V(m)n of enalapril+Hoe-140-treated group were higher than that of enalapril-treated group (P＜0.05) .CONCLUSION:Enalapril can prevent left ventricular hypertrophy and improve cardiac function independent of blood pressure after myocardial infarction, which is partly due to the inhibition of BK degradation.     

Effects of flavonoids isolated from Scutellaria stem and leaf on expression of NMDAR and VEGF in chronic cerebral ischemia rats

AIM: To study the effects of flavonoids isolated from Scutellaria stem and leaf (SSF) on the expression of N-methyl-D-aspartate receptor (NMDAR) and vascular endothelial growth factor (VEGF) in chronic cerebral ischemia rats. METHODS: The model of chronic cerebral ischemia was established by bilateral carotid artery occlusion for 2 months in female SD rats. The effects of SSF on mRNA expression of NMDAR in hippocampus and VEGF in cerebral cortex were evaluated by the method of RT-PCR. RESULTS: Compared with the sham group, the expression of NMDAR1, NMDAR2A and NMDAR2B in hippocampus and VEGF in cerebral cortex were significantly increased (P<0.01). However, the cerebral ischemia rats daily and orally administered with SSF at doses of 17.5 mg·kg^-1·d^-1, 35 mg·kg^-1·d^-1 and 70 mg·kg^-1·d^-1 for 38 days appeared that the mRNA expression of NMDAR1, NMDAR2A and NMDAR2B in hippocampus was obviously reduced (P<0.05), and the mRNA content of VEGF in the cortex (P<0.05) was increased. CONCLUSION: SSF decreases the expression of NMDAR in hippocampus, increases the expression of VEGF in cerebral cortex of cerebral ischemia rats, suggesting that the neuroprotective effect of SSF may be exerted by influencing the production of NMDAR and VEGF in the brain.     

Effects of metformin on pressure overload-induced cardiac hypertrophy in rats

AIM: To study the effects of metformin on the pressure overload-induced cardiac hypertrophy in rats. METHODS: Transverse aortic constriction (TAC) model of rat was made through laparotomy. One week after TAC surgery, the rats were randomly divided into 5 groups (n=8 in each group) and were administered with the corresponding drugs orally every day for 8 weeks: sham group (sham surgery, administered with 2 mL distilled water); TAC group (TAC rats, administered with 2 mL distilled water); metformin (MET) group (TAC rats, administered with MET at dose of 300 mg·kg^-1·d^-1); MN group [TAC rats, administered with MET at dose of 300 mg·kg^-1·d^-1 plus NOS inhibitor, N^G-nitro-L-arginine methyl ester (L-NAME) 50 mg·kg^-1·d^-1] and L-NAME group (TAC rats, administered with L-NAME at dose of 50 mg·kg^-1·d^-1). After treated for 8 weeks, the echocardiography, hemodynamics, the ratio of heart weight to body weight (HW/BW) and histological examination of the heart were performed. The levels of myocardial AMP-activated protein kinase subunit α (AMPKα), p-AMPKα Thr172, endothelial nitric oxide synthase (eNOS) and p-eNOS Ser1177 were detected by Western blotting. Plasma and myocardial nitric oxide (NO) were detected biochemically. RESULTS: After 8 weeks treatment, the wall thickness of left ventricle, the heart weight/body weight ratio (HW/BW), and the left ventricular myocardial perivascular fibrosis and myocardial interstitial fibrosis of the animals in TAC group were significantly increased as compared to those in sham rats. Treatment with MET for 8 weeks significantly attenuated left ventricular hypertrophy and improved cardiac function in TAC rats. These effects of MET were mostly abolished by L-NAME. Molecular biology and biochemical testing revealed that the levels of left ventricular myocardial p-AMPKα Thr172 and p-eNOS Ser1177, as well as the levels of myocardial and serum NO were significantly increased in MET group. CONCLUSION: Long-term MET treatment significantly inhibits the cardiac hypertrophy and the myocardial fibrosis and improves the cardiac functions in pressure-overload rats. The anti-hypertrophic effects of MET may be mediated via activation of AMPK-eNOS signaling pathway.     

Effects of ginsenoside Rh1 on expression of inflammatory factors in mouse asthma model

AIM: To observe the effects of ginsenoside Rh1 on the levels of inflammatory factors in serum and bronchoalveolar lavage fluid (BALF), and the pathological changes of the lung tissues in an experimentally induced mouse asthma model. METHODS: Male BALB/c mice (n=40) were divided into 4 groups:normal control group, asthma mo-del group, and low-dose (40 mg·kg^-1·d^-1) and high-dose (80 mg·kg^-1·d^-1) ginsenoside Rh1 groups. The bronchial asthma mouse model was established by the method of ovalbumin induction and excitation, and during the excitation period, the mice were daily treated with ginsenoside Rh1 for 2 weeks. At 24 h after the final dose of ginsenoside Rh1, the mice were sacrificed. The number of eosinophils (EOS) and the concentrations of interleukin (IL)-4, IL-5 and interferon (IFN)-γ in BALF were determined. The levels of IgG and IgE in serum were measured, and the expression of transforming growth factor (TGF)-β1 and the pathological changes in lung tissues were evaluated. RESULTS: Ginsenoside Rh1 inhibited the increases in the number of EOS and the concentrations of IL-4, IL-5, IFN-γ and IgE, reversed the increased expression of TGF-β1, and improved the pathological changes of the lung tissues in asthmatic mice. CONCLUSION: Ginsenoside Rh1 improves the immuno-inflammatory profile and pathological changes in the experimentally induced mouse asthma model, implying its potential therapeutic effect on asthma.