Abstract:Aim To explore the mechanism of ginsenoside Rb1 inhibiting arsenic sulfide-induced toxicity of neurocyte pheochromocytoma cells (PC12). Methods PC12 cells were treated with 0,2.5,5, 0,5, 0,0 μmol/L arsenic sulfide. Cell damage was observed, and cell viability was measured by thiazole blue method. 5,0, 20 μmol/L ginsenoside Rb1 was added into PC12 cell culture medium damaged by arsenic sulfide, and its effect on cell proliferation was detected by sulforhodamine B assay, cell apoptosis was detected by flow cytometry, ATP content in cells was detected by ATP kit luciferase assay, and intracellular reactive oxygen species (ROS) content was detected by 2′,7′-dichlorotetrafluoroethane diacetate probe dyeing. Western blot was used to detect the protein expressions of protein kinase B (AKT), glycogen synthase kinase 3β (GSK-3β), nuclear factor of activated T cell (NFAT), cytochrome C (Cyt C), cysteine protease 3 (Caspase-3), B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein (Bax) in PC12 cells. Results The PC12 cells were damaged by different concentrations of arsenic sulfide, with the increase of the concentration and the prolongation of the action time, the cell damage became more serious; Arsenic sulfide could inhibit the proliferation of PC12 cells. Ginsenoside Rb1 had protective effect on PC12 cells damaged by arsenic sulfide and could effectively inhibit apoptosis of PC12 cells induced by arsenic sulfide. Arsenic sulfide could decrease ATP content and increase ROS content in PC12 cells, and ginsenoside Rb1 could increase ATP content, reduce ROS content and enhance cell metabolism. After arsenic sulfide stimulation, the protein expressions of p-AKT, p-GSK-3β, NFAT-c3, Bcl-2 and Cleaved Caspase-3 in PC12 cells was significantly decreased, the protein expressions of Caspase-3 and Bax was significantly increased, and the expression of Cyt C in mitochondria was significantly increased (P＜0.01). After ginsenoside Rb1 intervention, the protein expressions of p-AKT, p-GSK-3β, NFAT-c3, Bcl-2 and Cleaved Caspase-3 increased significantly, the protein expressions of Caspase-3 and Bax decreased significantly, and the expression of Cyt C in mitochondria decreased significantly (P＜0.01). Conclusion Ginsenoside Rb1 can inhibit arsenic sulfide-induced apoptosis of PC12 cells and protect neurons, which may be achieved by regulating AKT/GSK-3β/NFAT signaling pathway.

Abstract:Aim To investigate whether Rb1 could block tumor necrosis factor-α(TNF-α)induced inflammation in human umbilical vein endothelial cell(HUVEC). Methods HUVEC were treated with TNF-α(0.5 μg/L) and/or Rb1(15 mg/L) for 16 hours.The mRNA level of vascular cell adhesion molecule-1(VCAM-1) was determined by real-time PCR and flow cytometry,respectively.Human macrophage THP-1 labeled with a fluorescent dye(Calcein-AM) was used for the adhesion assay on HUVEC monolayer.Dihydroethidium(DHE) was used to demonstrate in situ levels of superoxide production.JC-1 dye was used to measure changes in mitochondrial membrane potential. Results TNF-α treatment significantly increased the mRNA expression of VCAM-1 in HUVEC,as compared to controls.Rb1 pretreatment blocked the TNF-α induced mRNA expression of VCAM-1,and also effectively blocked THP-1 adhesions.Furthermore,Rb1 reduces TNF-α induced increase of superoxide anion production and inhibits TNF-α induced decrease of mitochondrial membrane potential in HUVEC. Conclusion These data suggested that Rb1 might have potential therapeutic effects in controlling inflammation in vascular diseases.