Peng Yanhua, Sigua Celia A, Karsonovich Cynthia, Murr Michel M
Department of Surgery, James A. Haley Veterans Affairs Medical Center, University of South Florida Health Sciences Center, C/O Tampa General Hospital, Tampa, FL 33601, USA.
J Gastrointest Surg. 2007 Dec;11(12):1712-21. doi: 10.1007/s11605-007-0314-9. Epub 2007 Sep 25.
Kupffer cells play an important role in sepsis-mediated liver injury. We tested the hypothesis that PKC-zeta plays a critical role in Kupffer cell apoptosis during sepsis.
Sepsis was induced in rats by cecal ligation and puncture (CLP); 12 h later, livers were assayed for PKC-zeta, IKKalpha, IKKbeta, IKKgamma, NF-kappaB, Fas/FasL, Caspase-3, and DNA fragmentation. Kupffer cells from control rats were infected with AdPKC-zeta DN to inhibit PKC-zeta, or transfected with pCMVPKC-zeta to overexpress PKC-zeta, and then treated with lipopolysaccharide (LPS). Cellular extracts were assayed for PKC-zeta, IKKalpha, IKKbeta, IKKgamma, NF-kappaB, Fas/FasL, Caspase-3, and DNA fragmentation.
During sepsis, PKC-zeta localized in cells positive for the macrophage marker (F4/80). CLP upregulated PKC-zeta protein and activity, IKKbeta, IKKgamma, NF-kappaB, Fas/FasL, Caspase-3, and increased DNA fragmentation in rat livers (all p<0.001). AdPKC-zeta DN attenuated the LPS-induced upregulation of PKC-zeta activity, IKKbeta, IKKgamma, NF-kappaB, Fas/FasL, Caspase-3, and DNA fragmentation in Kupffer cells (all p<0.001), whereas overexpression of PKC-zeta augmented LPS-induced upregulation of IKKbeta, IKKgamma, NF-kappaB, Caspase-3, and DNA fragmentation (p<0.001).
PKC-zeta plays an important role in sepsis-induced apoptosis of Kupffer cells via activation of NF-kappaB and Fas/FasL. Manipulating the response of Kupffer cells to cellular stress may have important therapeutic implications.
库普弗细胞在脓毒症介导的肝损伤中起重要作用。我们检验了蛋白激酶C-ζ（PKC-ζ）在脓毒症期间库普弗细胞凋亡中起关键作用这一假说。
通过盲肠结扎和穿刺（CLP）诱导大鼠发生脓毒症；12小时后，检测肝脏中的PKC-ζ、IKKα、IKKβ、IKKγ、核因子κB（NF-κB）、Fas/Fas配体（FasL）、半胱天冬酶-3（Caspase-3）以及DNA片段化情况。用腺病毒介导的PKC-ζ显性负性突变体（AdPKC-ζ DN）感染对照大鼠的库普弗细胞以抑制PKC-ζ，或用pCMV-PKC-ζ转染以过表达PKC-ζ，然后用脂多糖（LPS）处理。检测细胞提取物中的PKC-ζ、IKKα、IKKβ、IKKγ、NF-κB、Fas/FasL、Caspase-3以及DNA片段化情况。
在脓毒症期间，PKC-ζ定位于巨噬细胞标志物（F4/80）阳性的细胞中。CLP上调了大鼠肝脏中PKC-ζ蛋白和活性、IKKβ、IKKγ、NF-κB、Fas/FasL、Caspase-3，并增加了DNA片段化（均p<0.001）。AdPKC-ζ DN减弱了LPS诱导的库普弗细胞中PKC-ζ活性、IKKβ、IKKγ、NF-κB、Fas/FasL、Caspase-3以及DNA片段化的上调（均p<0.001），而PKC-ζ的过表达增强了LPS诱导的IKKβ、IKKγ、NF-κB、Caspase-3以及DNA片段化的上调（p<0.001）。
PKC-ζ通过激活NF-κB和Fas/FasL在脓毒症诱导的库普弗细胞凋亡中起重要作用。调控库普弗细胞对细胞应激的反应可能具有重要的治疗意义。
