Abstract:
Cardiac fibrosis is a severe outcome of Chagas disease (CD), caused by the protozoan Trypanosoma cruzi. Clinical evidence revealed a correlation between fibrosis levels with impaired cardiac performance in CD patients. Therefore, we sought to analyze the effect of inhibitors of TGF-β (pirfenidone), p38-MAPK (losmapimod) and c-Jun (SP600125) on the modulation of collagen deposition in cardiac fibroblasts (CF) and in vivo models of T. cruzi chronic infection. Sirius Red/Fast Green dye was used to quantify both collagen expression and total protein amount, assessing cytotoxicity. The compounds were also used to treat C57/Bl6 mice chronically infected with T. cruzi, Brazil strain. We identified an anti-fibrotic effect in vitro for pirfenidone (TGF-β inhibitor, IC50 114.3 μM), losmapimod (p38 inhibitor, IC50 17.6 μM) and SP600125 (c-Jun inhibitor, IC50 3.9 μM). This effect was independent of CF proliferation since these compounds do not affect T. cruzi-induced host cell multiplication as measured by BrdU incorporation. Assays of chronic infection of mice with T. cruzi have shown a reduction in heart collagen by pirfenidone. These results propose a novel approach to fibrosis therapy in CD, with the prospect of repurposing pirfenidone to prevent the onset of ECM accumulation in the hearts of the patients.
摘要:
心脏纤维化是恰加斯病(CD)的严重结果,由原生动物克氏锥虫引起的。临床证据表明,CD患者的纤维化水平与心脏功能受损之间存在相关性。因此,我们试图分析TGF-β(吡非尼酮)抑制剂的作用,p38-MAPK(losmapimod)和c-Jun(SP600125)对心肌成纤维细胞(CF)胶原沉积的调控作用及其在克氏滴虫慢性感染体内模型中的作用.天狼星红/固绿染料用于量化胶原蛋白表达和总蛋白量,评估细胞毒性。这些化合物还用于治疗C57/Bl6小鼠,巴西应变。我们确定了吡非尼酮(TGF-β抑制剂,IC50114.3μM),洛斯马莫德(p38抑制剂,IC5017.6μM)和SP600125(c-Jun抑制剂,IC503.9μM)。这种作用与CF增殖无关,因为这些化合物不影响克氏毛虫诱导的宿主细胞增殖,如通过BrdU掺入所测量的。用T.cruzi对小鼠的慢性感染的测定显示,吡非尼酮减少了心脏胶原蛋白。这些结果提出了一种新的CD纤维化治疗方法,有可能重新利用吡非尼酮来预防ECM在患者心脏中的积累。