目的观察硫酸多糖聚甘古酯(SPMG)对HIV-1反式转录调节蛋白(Tat)刺激THP-1细胞释放具有神经毒性的炎症细胞因子如TNFα,IL-1β和IL-6的影响,并探讨其作用机制。方法用ELISA法检测SPMG对Tat刺激4h细胞上清液TNFα、刺激6h细胞上清液IL-1β和IL-6的影响;用Western blotting技术检测SPMG对PKCζ,PKCθ与PKCδ磷酸化影响。结果SPMG(50~100μg·mL^-1)显著抑制Tat诱导的TNFα,IL-1β与IL-6释放;Tat显著促进PKCζ,PKCθ和PKCδ的磷酸化,SPMG对PKCδ与PKCθ的磷酸化没有影响,但显著抑制PKCδ的磷酸化。结论SPMG可能通过抑制Tat对PKCδ活化,抑制炎症细胞因子TNFα,IL-6与IL-1β释放。
Aim To investigate the effects of sulfated polymannuroguluronate (SPMG), a novel candidate anti-AIDS drug in Phase II clinical trial, on Tat-induced release of proinflammatory cytokines (i. e. , TNFα, IL-1β and IL-6) and its related mechanism. Methods The effects of SPMG on Tat induced TNFα (4 h) , IL-1β and IL-6 (6 h) secretion in THP-1 cells were measured by ELISA. Western blotting analysis was used to study the effects of SPMG on Tat induced PKCζ, PKCθ and PKCδ phosphorylation. Results SPMG (50 to 100 μg·mL^-1) markedly suppressed TNFα, IL-1β and IL-6 secretion in Tat activated THP-1 cells. In THP-1 cells the phosphorylation levels of PKCζ, PKCθ and PKCδ significantly increased following Tat stimulation, and only PKCδ phosphorylation levels was inhibited by SPMG (50 to 100 μg·mL^-1). Conclusion SPMG suppresses the secretion of proinflammatory cytokines in THP-1 cells may be by inhibiting PKCδ activation.