OBJECTIVES: To study the mechanism mediating the protective effect of asiaticoside (AS) against myocardial ischemia-reperfusion injury (MIRI) in rats. METHODS: Fifty SD rats were randomized into sham-operated group, MIRI model group and AS treatment group. AS treatment was administered at low, moderate and high doses by daily gavage for 2 weeks before MIRI modeling (n=10). Serum levels of lactate dehydrogenase (LDH), creatine kinase isoenzyme (CK-MB), interleukin-18 (IL-18) and IL-1β, the volume of myocardial infarction and ischemia, and myocardial pathologies of the rats were determined or observed. The protein expression levels of NLRP3, ASC, caspase-1, GSDMD, GSDMD-N, IL-1β and IL-18 in the myocardial tissues were detected using Western blotting. The changes in the expression levels of these proteins were also detected in H9C2 cells with AS pretreatment prior to hypoxia-reoxygenation (H/R) injury. RESULTS: The rats models of MIRI exhibited significant myocardial infarction and ischemia with increased serum levels of LDH and CK-MB and myocardial expressions of NLRP3, ASC, caspase-1, GSDMD, GSDMD-N, IL-1β and IL-18. AS pretreatment effectively reduced myocardial infarction volume in the rat models and significantly reduced serum LDH and CK-MB levels and the protein levels in the myocardial tissue in a dose-dependent manner. In the H9C2 cell model of H/R injury, AS pretreatment significantly suppressed the elevation of the protein expressions of NLRP3, ASC, caspase-1, GSDMD, GSDMD-N, IL-1β and IL-18. Molecular docking studies showed that AS had a strong binding affinity with NLRP3. CONCLUSIONS Asiaticoside can alleviate MIRI in rats possibly by inhibiting NLRP3 inflammasome-mediated pyroptosis.
Animals ; Myocardial Reperfusion Injury/metabolism* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Pyroptosis/drug effects* ; Rats, Sprague-Dawley ; Rats ; Inflammasomes/metabolism* ; Triterpenes/pharmacology* ; Interleukin-18/metabolism* ; Male ; Interleukin-1beta/metabolism* ; Caspase 1/metabolism*

Objective To investigate whether activation of mitochondrial acetal dehydrogenase 2(ALDH2)alleviates hypoxic pulmonary hypertension by regulating the SIRT1/PGC-1α signaling pathway.Methods Thirty 8-week-old C57 BL/6 mice were randomized into control,hypoxia,and hypoxia+Alda-1(an ALDH2 activator)group(n=10),and the mice in the latter two groups,along with 10 ALDH2 knockout(ALDH2-/-)mice,were exposed to hypoxia(10%O2,90%N2)with or without daily intraperitoneal injection of Alda-1 for 4 weeks.The changes in right ventricular function and pressure(RVSP)of the mice were evaluated by echocardiography and right ventricular catheter test,and pulmonary artery pressure was estimated based on RVSP.Pulmonary vascular remodeling,right ventricular injury,myocardial α-SMA expression,distal pulmonary arteriole muscle normalization,right ventricular cross-sectional area,myocardial cell hypertrophy,and right cardiac hypertrophy index were assessed with HE staining,immunofluorescence staining and WGA staining,and the expressions of ALDH2,SIRT1,PGC-1α,P16INK4A and P21CIP1 were detected.In pulmonary artery smooth muscle cells with hypoxic exposure,the effect of Alda-1 and EX527 on cell senescence and protein expressions was evaluated using β-galactose staining and Western blotting.Results The wild-type mice with hypoxic exposure showed significantly increased RVSP,right ventricular free wall thickness and myocardial expressions of P16INK4A and P21CIP1,which were effectively lowered by treatment with Alda-1 but further increased in ALDH2-/-mice.In cultured pulmonary artery smooth muscle cells,hypoxic exposure significantly increased senescent cell percentage and cellular expressions of P16INK4A and P21CIP1,which were all lowered by treatment with Alda-1,but its effect was obviously attenuated by EX527 treatment.Conclusion ALDH2 alleviates hypoxia-induced senescence of pulmonary artery smooth muscle cells by upregulating the SIRT1/PGC-1α signaling pathway to alleviate pulmonary hypertension in mice.

Objective To investigate whether activation of mitochondrial acetal dehydrogenase 2(ALDH2)alleviates hypoxic pulmonary hypertension by regulating the SIRT1/PGC-1α signaling pathway.Methods Thirty 8-week-old C57 BL/6 mice were randomized into control,hypoxia,and hypoxia+Alda-1(an ALDH2 activator)group(n=10),and the mice in the latter two groups,along with 10 ALDH2 knockout(ALDH2-/-)mice,were exposed to hypoxia(10%O2,90%N2)with or without daily intraperitoneal injection of Alda-1 for 4 weeks.The changes in right ventricular function and pressure(RVSP)of the mice were evaluated by echocardiography and right ventricular catheter test,and pulmonary artery pressure was estimated based on RVSP.Pulmonary vascular remodeling,right ventricular injury,myocardial α-SMA expression,distal pulmonary arteriole muscle normalization,right ventricular cross-sectional area,myocardial cell hypertrophy,and right cardiac hypertrophy index were assessed with HE staining,immunofluorescence staining and WGA staining,and the expressions of ALDH2,SIRT1,PGC-1α,P16INK4A and P21CIP1 were detected.In pulmonary artery smooth muscle cells with hypoxic exposure,the effect of Alda-1 and EX527 on cell senescence and protein expressions was evaluated using β-galactose staining and Western blotting.Results The wild-type mice with hypoxic exposure showed significantly increased RVSP,right ventricular free wall thickness and myocardial expressions of P16INK4A and P21CIP1,which were effectively lowered by treatment with Alda-1 but further increased in ALDH2-/-mice.In cultured pulmonary artery smooth muscle cells,hypoxic exposure significantly increased senescent cell percentage and cellular expressions of P16INK4A and P21CIP1,which were all lowered by treatment with Alda-1,but its effect was obviously attenuated by EX527 treatment.Conclusion ALDH2 alleviates hypoxia-induced senescence of pulmonary artery smooth muscle cells by upregulating the SIRT1/PGC-1α signaling pathway to alleviate pulmonary hypertension in mice.

Objective To study the effect of nerve growth factor(NGF)in survival of super-length random flap.Methods The experiment employed the animal model of random flap in Wistar's rat back,applied 66.7 μg NGF locally in trial group's flap at the first day after operation with auto-control.The survival proportion,skin temperature and survival rate of random flap were observed,and the blood flow,the blood flow velocity,the blood flow volume change of random flap were measured by the laser and photic-conduct fiber means in differ time.Results The survival proportion(7.12±1.54)cm2 and survival rate(92±5)%of random flap of trial group was obviously higher(P＜0.05)than those in control group[(5.23±0.19)cm2,(69±5)%]after pedicle division.The blood flow,the blood flow velocity,the blood flow volume and skin temperature in the midge and at the end of random flap in the trial group were obviously higher than those in control group 1 day after operation(P＜0.05),and the blood flow velocity in the pedicle of random flap in the trial group was increased markedly(P＜0.05).The blood flow volume and skin temperature in the pedicle of random flap in the trial group were higher than those in control group 3 days after operation(P＜0.05).The survival of randomflapinthetrial groupwere very significantly increased than those in control group 7 days after operation(P＜0.01).Conclusion NGF can increase flap's blood flow,blood flow velocity and blood flow volume,enhancing survival of the big-proportioned and super-length random flap.

Objective To examine the chracteristics of distribution of the FGF R before and after the flap transplantation and the influence of exogenic bFGF on the distribution of FGF R. Method Caudally based random skin flaps were raised on the backs of Wistar rats,bFGF was instilled under flaps after closure.An immunohistochemical techniques stanining method was used. Results FGF receptors distributes in the stratum basal of epidermis,the vascular endothelial cells in the dermis and hypodermis,the fibroblasts and the epithelial cells of the hair follicle and the sweat gland.In compared with preoperation,the quantity of increased gradually from the 1st day to the fifth day after operation,and the peak value is on the fifth day,it then recovered to the pre operation level on the serventh day.After applying the exogenic bFGF,the positive immunoreactive cells in the experimental group,increased remarkably from the Ist day to the 3rd day after operation in contrast with the control group.The peak value is on the 3rd day which was two days earlier than that of the control group and the peak value of the experimental group is remarkably higher than that of the control group.Conclusion\ FGF R distributes in the stratum basal of epidermis,the vascular endothelial cells in the dermis and hypodermis,the fibroblasts,and the epithelial cells of the hair follicle and the sweat gland.In compaired with pre operation,the quantity of the positive immunoreactive cells of FGF R were increased gradually from the Ist day to fifth day after operation,and the peak value is on the fifth day.After applying the exogenic bFGF,the positive immunoreactive cells of FGF receptors were increased.\;[