Department of Pathology, Xijing Hospital, Fourth Military Medical University, 15 Changle Western Road, 710032, Xi'an, People's Republic of China.
Nephrol Dial Transplant. 2010 Jul;25(7):2125-33. doi: 10.1093/ndt/gfp737. Epub 2010 Jan 29.
The pathogenesis of hepatitis B virus (HBV)-associated glomerulonephritis (HBVGN) is generally believed to be immune complex deposition. However, the presence of HBV-DNA and -RNA in HBVGN renal tissues suggested a direct virally induced injury. We previously showed that nuclear factor kappaB (NF-kappaB) was activated in HBVGN renal tissues, especially in tubular cells. We therefore investigated the role of NF-kappaB in tubular epithelial cells with HBV infection.
Nuclear translocation of NF-kappaB and alpha subunit of NF-kappaB inhibitor (IkappaBalpha) phosphorylation were assessed by immunodetection following transfection of HK-2 cells with mhbs(t167) and/or hbx. Electrophoretic mobility shift assays (EMSA) and dual luciferase reporter assays (DLR) were used to further examine NF-kappaB activation following transfection. Hochest 33258 and NF-kappaB/terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) double staining were used to detect apoptosis and the correlation between NF-kappaB activation and apoptosis. Protein kinase C (PKC) assay and ERK phosphorylation were assayed for a possible mechanism of NF-kappaB activation.
Cells transfected with mhbs(t167) and/or hbx increased NF-kappaB nuclear translocation, phosphor-IkappaBalpha, kappaB-DNA binding activity, kappaB-dependent transcription and apoptotic index compared to controls (P < 0.05). The nuclear distribution of NF-kappaB strongly correlated to cellular apoptosis. PKC activity and phosphor-ERK were also increased (P < 0.05) during the NF-kappaB activation process. However, all above parameters were diminished after pyrrolidine dithiocarbamate (PDTC)-incubation, a NF-kappaB inhibitor (P < 0.05).
MHBs(t167)/HBx-induced NF-kappaB activation via the PKC/ERK pathway in renal tubular cells undergoing apoptosis may be involved in virally induced pathogenesis.
乙型肝炎病毒（HBV）相关性肾小球肾炎（HBVGN）的发病机制一般认为是免疫复合物沉积。然而，HBVGN 肾组织中存在 HBV-DNA 和 -RNA 表明存在直接的病毒诱导损伤。我们之前的研究表明，核因子 kappaB（NF-kappaB）在 HBVGN 肾组织中被激活，尤其是在肾小管细胞中。因此，我们研究了 HBV 感染肾小管上皮细胞中 NF-kappaB 的作用。
通过转染 HK-2 细胞 mhbs(t167)和/或 hbx 后，通过免疫检测评估 NF-kappaB 的核易位和 NF-kappaB 抑制剂（IkappaBalpha）磷酸化。电泳迁移率变动分析（EMSA）和双荧光素酶报告基因分析（DLR）用于进一步检测转染后 NF-kappaB 的激活。Hochest 33258 和 NF-kappaB/末端脱氧核苷酸转移酶 dUTP 缺口末端标记（TUNEL）双重染色用于检测凋亡和 NF-kappaB 激活与凋亡之间的相关性。蛋白激酶 C（PKC）测定和 ERK 磷酸化用于研究 NF-kappaB 激活的可能机制。
转染 mhbs(t167)和/或 hbx 的细胞与对照组相比，NF-kappaB 核易位、磷酸化 IkappaBalpha、kappaB-DNA 结合活性、kappaB 依赖性转录和凋亡指数均增加（P < 0.05）。NF-kappaB 的核分布与细胞凋亡强烈相关。PKC 活性和 phosphor-ERK 也在 NF-kappaB 激活过程中增加（P < 0.05）。然而，在用 NF-kappaB 抑制剂吡咯烷二硫代氨基甲酸盐（PDTC）孵育后，所有上述参数均降低（P < 0.05）。
HBV 诱导的肾小管细胞凋亡中，MHBs(t167)/HBx 通过 PKC/ERK 通路诱导 NF-kappaB 激活，可能参与病毒诱导的发病机制。
