乙肝病毒X蛋白通过激活JAK2/STAT3信号通路调节肾小管上皮细胞凋亡

HBx modulates apoptosis by activating JAK2 /STAT3 signaling pathway in human renal proximal tubular epithelial cells

目的:观察乙肝病毒X蛋白(HBx)对肾小管上皮细胞凋亡的作用,并探讨其在乙型病毒肝炎相关性肾炎(HBVGN)发病中的分子机制。方法:将构建好的HBx真核表达载体pcDNA3.1(+)-HBx转染至体外培养的人肾近曲小管上皮细胞(HK-2细胞)中。Western blotting法检测转染后目的蛋白的表达及JAK2/STAT3信号通路的活化。细胞免疫荧光检测STAT3及p-STAT3表达水平。CCK-8法检测细胞增殖活性。Hoechst 33342染色观察细胞的形态学改变。透射电镜观察细胞的超微结构及凋亡。Annexin V/PI双染流式细胞术检测细胞凋亡率。结果:转染目的基因HBx后,p-JAK2及p-STAT3表达水平均显著增加;同时,细胞增殖明显受抑。透射电镜、Hoechst 33342染色及Annexin V/PI双染流式细胞术检测发现HBx促进HK-2细胞凋亡。AG490(JAK2/STAT3信号通路阻断剂)孵育后能够部分阻断JAK2/STAT3信号通路,减少HBx所致细胞凋亡。结论:HBx通过激活JAK2/STAT3信号通路导致肾小管上皮细胞凋亡,可能参与了HBV直接损伤肾组织的致病机制。

AIM： To investigate the correlation of hepatitis B virus X protein （HBx） with renal tubular epithelialcell apoptosis in hepatitis B virus-associated glomerulonephritis （HBVGN） and the possible signaling mechanism. METHODS： The activation of JAK2/STAT3 signal pathway and the expression of apoptosis -related proteins in humankindey proximal tubular epithelial cells （HK-2 cells） were determined by Western blotting after transfection with HBx eukaryoticexpression vector.The cell proliferation was observed by CCK-8 assay.The cell apoptosis was analyzed by the imagingof HO33342 staining, transmission electron microscopy and flow cytometry with Annexin V /PI double staining.RESULTS：After transfection of the target gene HBx, the expression levels of both p-JAK2 and p-STAT3 were significantly increased.At the same time, the cell proliferation was obviously inhibited, and the apoptotic rate was increased.After incubationwith AG490, the JAK2/STAT3 signal pathway was partially blocked, and the cell apoptosis induced by HBx was reduced. CONCLUSION： HBx up-regulates the activation of JAK2/STAT3 signal pathway to induce renal tubular epithelialcell apoptosis, which is possibly involved in the pathogenic mechanism that HBV directly damages nephridial tissue .