Kanak Mazhar A, Shahbazov Rauf, Yoshimatsu Gumpei, Levy Marlon F, Lawrence Michael C, Naziruddin Bashoo
Institute of Biomedical Studies, Baylor University, Waco, TX, USA.
Department of Surgery, Transplantation Division, Virginia Commonwealth University, Richmond, VA, USA.
J Gastroenterol. 2017 Mar;52(3):352-365. doi: 10.1007/s00535-016-1238-5. Epub 2016 Jul 14.
The underlying molecular mechanism that leads to development of chronic pancreatitis remains elusive. The aim of this study is to understand the downstream inflammatory signaling involved in progression of chronic pancreatitis, and to use withaferin A (WA), a small molecule inhibitor of nuclear factor κB (NFκB), to prevent progression of chronic pancreatitis.
Two different protocols were used to induce pancreatitis in mice: standard and stringent administration of cerulein. The severity of pancreatitis was assessed by means of pancreatic histology and serum amylase levels. Immunohistochemistry and flow-cytometric analysis was performed to visualize immune cell infiltration into the pancreas. Real-time PCR and Western blot were used to analyze the downstream signaling mechanism involved in the development of chronic pancreatitis.
The severity of cerulein-induced pancreatitis was reduced significantly by WA, used as either preventive or curative treatment. Immune cell infiltration into the pancreas and acinar cell death were efficiently reduced by WA treatment. Expression of proinflammatory and proapoptotic genes regulated by NFκB activation was increased by cerulein treatment, and WA suppressed these genes significantly. Sustained endoplasmic reticulum stress activation by cerulein administration was reduced. NLRP3 inflammasome activation in cerulein-induced pancreatitis was identified, and this was also potently blocked by WA. The human pancreatitis tissue gene signature correlated with the mouse model.
Our data provide evidence for the role of NFκB in the pathogenesis of chronic pancreatitis, and strongly suggest that WA could be used as a potential therapeutic drug to alleviate some forms of chronic pancreatitis.
导致慢性胰腺炎发生的潜在分子机制仍不清楚。本研究的目的是了解慢性胰腺炎进展过程中涉及的下游炎症信号，并使用核因子κB（NFκB）的小分子抑制剂牛膝甾酮A（WA）来预防慢性胰腺炎的进展。
采用两种不同方案在小鼠中诱导胰腺炎：标准剂量和严格剂量的雨蛙素给药。通过胰腺组织学和血清淀粉酶水平评估胰腺炎的严重程度。进行免疫组织化学和流式细胞术分析以观察免疫细胞浸润到胰腺中的情况。采用实时聚合酶链反应（PCR）和蛋白质免疫印迹法分析慢性胰腺炎发生过程中涉及的下游信号传导机制。
无论是作为预防性还是治疗性用药，WA均可显著减轻雨蛙素诱导的胰腺炎的严重程度。WA治疗有效减少了免疫细胞浸润到胰腺以及腺泡细胞死亡的情况。雨蛙素治疗可增加由NFκB激活调节的促炎和促凋亡基因的表达，而WA可显著抑制这些基因。雨蛙素给药引起的内质网应激持续激活得到减轻。在雨蛙素诱导的胰腺炎中发现了NLRP3炎性小体激活，而WA也能有效阻断这种激活。人类胰腺炎组织基因特征与小鼠模型相关。
我们的数据为NFκB在慢性胰腺炎发病机制中的作用提供了证据，并强烈表明WA可作为一种潜在的治疗药物来缓解某些形式的慢性胰腺炎。
