人参皂苷Rb1抗单纯疱疹病毒1型感染及保护神经的实验研究

目的 通过研究人参皂苷Rb1(GRb1)抑制单纯疱疹病毒1型(herpes simplex virus, HSV-1)感染导致人星形胶质瘤细胞(U251)凋亡异常及神经生长因子(NGF)mRNA的表达变化，探讨GRb1 抗HSV-1 感染从而保护神经的作用机制。方法 MTT比色法、流式细胞术检测GRb1对HSV-1感染致U251细胞凋亡异常的抑制作用;应用半定量RT-PCR检测不同处理组NGF mRNA的表达变化。结果 (1)MTT法显示400 μg/mL GRb1+HSV-1组在感染24、36、48 h的MTT值均高于HSV-1组 (P<0.05)；(2)形态学观察HSV-1组细胞感染36 h后出现细胞病变效应(CPE)，而400 μg/mL GRb1+HSV-1组细胞感染36 h后融合增多，但大部分细胞为正常形态；(3)流式细胞术显示： 400 μg/mL GRb1+HSV-1组凋亡率在感染24、36 h均低于HSV-1组 (P<0. 05)；(4)RT-PCR显示：400 μg/mL GRb1+HSV-1组GRb1组在加药后早期6～12 h NGF mRNA表达降低(P<0.05)，但在感染24、36、48 h 表达增高且明显高于HSV-1组(P<0.05)。结论 适当浓度的GRb1能抑制因HSV-1感染所致细胞凋亡的异常及NGF mRNA的表达变化。推测GRb1可能通过上调NGF mRNA的表达并抑制细胞凋亡，从而起到抗病毒、保护神经的作用。

Experimental Study of Ginsenoside Rb1 on Herpes Simplex Virus-1 Infection for Protecting Nerves

Objective To explore the action mechanism of ginsenoside Rb1(GRb1) on protecting herpes simplex virus-1(HSV-1) infected nerves by studying its inhibitory effects on abnormal changes of apoptosis and nerve growth factor(NGF) mRNA expression in HSV-1 infected human glioma cells U251.Methods The inhibitory effects of GRb1 on HSV-1 induced abnormal apoptosis of U251 cells were detected using MTT colorimetry and flow cytometry.The NGF mRNA expressions in different treatment groups were detected using semi-quantitative RT-PCR.Results(1) In 400 μg/mL GRb1+HSV-1 group,MTT value was higher than HSV-1 group at 24,36,and 48 h after infection(P<0.05).(2) Cytopathic effects(CPE) were observed in HSV-1 group at 36 h after infection.In 400 μg/mL GRb1+HSV-1 group merges increased at 36 h after infection,but most cells were in normal shapes.(3) Results of flow cytometry showed that the cell apoptosis rate was lower in 400 μg/mL GRb1+HSV-1 group than in the HSV-1 group at 24 and 36 h after infection(P<0.05).(4) Results of RT-PCR showed that in 400 μg/mL GRb1+HSV-1 group,NGF mRNA expressions decreased at 6-12 h after infection(P<0.05),but it increased at 24,36,and 48 h after infection,and was obviously higher than that in the HSV-1 group(P<0.05).Conclusions GRb1 at an appropriate concentration could inhibit abnormal cell apoptosis and changes of NGF mRNA expressions in HSV-1 infection.Therefore,we inferred that GRb1 could protect nerves possibly through up-regulating NGF mRNA expressions and inhibiting apoptosis.