Ginseng Saponin Rg1 Ischemic Limb Angiogenesis Research Promote Diabetes Mice

Objective: To induce mouse model of diabete and unilateral hindlimb ischemia.Methods: Mice were injected intraperitoneally with50mg/kg body weight ofStreptozotocin（STZ）dissolved in citrate buffer (pH4.5) for5days. One week afterthe fifth injection, diabetes was confirmed by fasting glucose levels equal to or higherthan11.1mM. Vein blood glucose concentrations were measured using glucoseoxidase method. Mice were intraperitoneally anesthetized with pentobarbital sodium(50mg/kg) and the common femoral vein and femoral nerve were dissected free ofthe artery. Two ligations were performed in the right common femoral artery proximalto the origin of the profunda femoris artery. The common femoral artery was thentransected between the ligation sites.Results: One week after the fifth injection, all male C57BL/6J mice developeddiabetes and fasting glucose levels higher than11.1mM maintain during theexperiment. All C57BL/6J mice were successfully induced to unilateral hindlimbischemia model.Conclusion: STZ is a simple, practicable and reliable agent to induce diabeteswith a high achievement ratio. Femoral artery ligation provides for a simpler model ofischemic tissue. Moreover, advantages of this model are the ease of access to thefemoral artery and low mortality rate. The mouse hindlimb ischemia preparation is agood model of peripheral arterial disease (PAD). Objective: To investigate the effects of Rg1treatment on blood glucose and bodyweight.Methods: STZ-DM mice were randomly divided into the following two groupsfor intraperitoneal treatment: Rg1-treated group (10mg/kg/day) and saline-treatedgroup (saline, volume0.1ml). Nondiabetic mice were randomly divided intosaline-treated control group (saline, volume0.1ml) and Rg1-treated control group (10mg/kg/day). Mice were fasted for18h (from6p.m. to1p.m.), Animal tail vein bloodglucose concentrations and fasting weight were measured1week after STZadministration as well as both1week and4weeks after Rg1treatment. Time courseeffect analysis: To further explore the time course effect of Rg1treatment on glucoselevel, after1week of Rg1or saline treatment, STZ-DM mice were fasted for6h(from8a.m. to2p.m.), and then received Rg1(10mg/kg) or saline(0.1ml)intraperitoneal injection. The blood glucose levels at the time point of0,30,60,120,180minute were measured, respectively.Results: The fasting body weight were lower two weeks after STZ treatmentcompared with saline-treated mice. Interestingly, Rg1administration for4weekscorrected the STZ-induced body weight loss. Fasting blood glucose levels werehigher one week after STZ treatment compared with saline-treated mice. There wasno significant difference of baseline fasting glucose levels between the saline-treateddiabetic group and Rg1-treated diabetic group. Likewise, when detected both1weekand4weeks after Rg1treatment, the fasting glucose levels were still similar betweenthe two groups. The time course effect of Rg1treatment on glucose level indicatedthat there was no significant change compared with0h in Rg1-treated diabetic group.Conclusion: Rg1administration for4weeks corrected the STZ-induced bodyweight loss. However, Rg1did not possess anti-diabetic activity. Objective: To investigate whether Rg1could improve angiogenesis in ischemichindlimb of diabetic mice in vivo.Methods: STZ-DM mice were randomly divided into the following two groupsfor intraperitoneal treatment: Rg1-treated group (10mg/kg/day) and saline-treatedgroup (saline, volume0.1ml). Nondiabetic mice were randomly divided intosaline-treated control group (saline, volume0.1ml) and Rg1-treated control group (10mg/kg/day). Rg1treatment was started8days before surgical induction of unilaterallimb ischemia and maintained after operation for3weeks. Unilateral hindlimbischemia was created in all groups. After3weeks of operation, laser Dopplerperfusion imaging was performed to assess the superficial blood flow of both feet. At21days after surgery, ischemic muscle was harvested for CD31, TUNEL and VEGFimmunohistological assessments and for eNOS, phospho-eNOS and VEGF proteindetection using western blot and ELISA assay, respectively.Results: The prevalence of toe necrosis occurred in Rg1-treated diabetic mice waslower compared with saline-treated diabetic group. After Rg1treatment, the ischemicfoot perfusion was improved in both diabetic and non-diabetic control mice, asdocumented by laser Doppler. Moreover, Rg1treatment could also significantlyactivate eNOS phosphorylation, increase the expression level of VEGF protein, andinhibit cell apoptosis in ischemic tissues.Conclusion: Diabetes impairs endogenous neovascularization of ischemic tissues.Notably, Rg1can promote angiogenesis and blood reperfusion recovery in bothdiabetic and non-diabetic control mice. Rg1may be used as a novel useful adjunctivedrug for the therapy of PAD in DM.