Department of Microbiology & Immunology and Internal Medicine/Gastroenterology and McGuire Veterans Affairs Medical Center, Virginia Commonwealth University, Richmond, Virginia, United States of America.
PLoS One. 2010 Feb 9;5(2):e9069. doi: 10.1371/journal.pone.0009069.
HIV protease inhibitor (PI)-induced inflammatory response plays an important role in HIV PI-associated dyslipidemia and cardiovascular complications. This study examined the effect of berberine, a traditional herb medicine, on HIV PI-induced inflammatory response and further investigated the underlying cellular/molecular mechanisms in macrophages.
Cultured mouse J774A.1 macrophages and primary mouse macrophages were used in this study. The expression of TNF-alpha and IL-6 were detected by real-time RT-PCR and ELISA. Activations of ER stress and ERK signaling pathways were determined by Western blot analysis. Immunofluorescent staining was used to determine the intracellular localization of RNA binding protein HuR. RNA-pull down assay was used to determine the association of HuR with endogenous TNF-alpha and IL-6. Berberine significantly inhibited HIV PI-induced TNF-alpha and IL-6 expression by modulating ER stress signaling pathways and subsequent ERK activation, in turn preventing the accumulation of the RNA binding protein HuR in cytosol and inhibiting the binding of HuR to the 3'-UTRs of TNF-alpha and IL-6 in macrophages.
Inhibition of ER stress represents a key mechanism by which berberine prevents HIV PI-induced inflammatory response. Our findings provide a new insight into the molecular mechanisms of berberine and show the potential application of berberine as a complimentary therapeutic agent for HIV infection.
HIV 蛋白酶抑制剂（PI）诱导的炎症反应在 HIV PI 相关血脂异常和心血管并发症中起着重要作用。本研究探讨了黄连素（一种传统草药）对 HIV PI 诱导的炎症反应的影响，并进一步研究了其在巨噬细胞中的潜在细胞/分子机制。
本研究使用了培养的小鼠 J774A.1 巨噬细胞和原代小鼠巨噬细胞。通过实时 RT-PCR 和 ELISA 检测 TNF-α和 IL-6 的表达。通过 Western blot 分析测定内质网应激和 ERK 信号通路的激活。免疫荧光染色用于确定 RNA 结合蛋白 HuR 的细胞内定位。RNA 下拉实验用于确定 HuR 与内源性 TNF-α和 IL-6 的结合。黄连素通过调节内质网应激信号通路和随后的 ERK 激活，显著抑制 HIV PI 诱导的 TNF-α和 IL-6 表达，从而阻止 RNA 结合蛋白 HuR 在细胞质中的积累，并抑制 HuR 与 TNF-α和 IL-6 的 3'-UTR 的结合。
抑制内质网应激代表了黄连素预防 HIV PI 诱导的炎症反应的关键机制。我们的研究结果为黄连素的分子机制提供了新的见解，并显示了黄连素作为 HIV 感染辅助治疗剂的潜在应用。
