da Rocha Gustavo Henrique Oliveira, de Paula-Silva Marina, Broering Milena Fronza, Scharf Pablo Rhasan Dos Santos, Matsuyama Larissa Satiko Alcântara Sekimoto, Maria-Engler Silvya Stuchi, Farsky Sandra Helena Poliselli
Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil.
Front Pharmacol. 2020 Dec 21;11:591561. doi: 10.3389/fphar.2020.591561. eCollection 2020.
Ulcerative colitis and Crohn's disease are chronic inflammatory bowel diseases (IBDs) which burden health systems worldwide; available pharmacological therapies are limited and cost-intensive. Use of peroxisome proliferator activated-receptor γ (PPARγ) ligands for IBD treatment, while promising, lacks solid evidences to ensure its efficacy. Annexin A1 (AnxA1), a glucocorticoid-modulated anti-inflammatory protein, plays a key role on IBD control and is a potential biomarker of IBD progression. We here investigated whether effects of pioglitazone, a PPARγ ligand, rely on AnxA1 actions to modulate IBD inflammation. Experimental colitis was evoked by 2% dextran sodium sulfate (DSS) in AnxA1 knockout (AnxA1) or wild type (WT) C57BL/6 mice. Clinical and histological parameters were more severe for AnxA than WT mice, and 10 mg/kg pioglitazone treatment attenuated disease parameters in WT mice only. AnxA1 expression was increased in tissue sections of diseased WT mice, correlating positively with presence of CD68 macrophages. Metalloproteinase-9 (MMP-9) and inactive 33 kDa AnxA1 levels were increased in the colon of diseased WT mice, which were reduced by pioglitazone treatment. Cytokine secretion, reactive oxygen species generation and MMP-9 expression caused by lipopolysaccharide (LPS) treatment in AnxA1-expressing RAW 264.7 macrophages were reduced by pioglitazone treatment, effects not detected in AnxA1 knockdown macrophages LPS-mediated increase of AnxA1 cleaving in RAW 264.7 macrophages was also attenuated by pioglitazone treatment. Finally, pioglitazone treatment increased extracellular signal-regulated kinase (ERK) phosphorylation in AnxA1-expressing RAW 264.7 macrophages, but not in AnxA1-knockdown macrophages. Thus, our data highlight AnxA1 as a crucial factor for the therapeutic actions of pioglitazone on IBDs.
溃疡性结肠炎和克罗恩病是慢性炎症性肠病（IBD），给全球卫生系统带来负担；现有的药物治疗有限且成本高昂。使用过氧化物酶体增殖物激活受体γ（PPARγ）配体治疗IBD虽然前景广阔，但缺乏确凿证据来确保其疗效。膜联蛋白A1（AnxA1）是一种糖皮质激素调节的抗炎蛋白，在IBD控制中起关键作用，是IBD进展的潜在生物标志物。我们在此研究了PPARγ配体吡格列酮的作用是否依赖于AnxA1的作用来调节IBD炎症。在AnxA1基因敲除（AnxA1）或野生型（WT）C57BL/6小鼠中，用2%葡聚糖硫酸钠（DSS）诱发实验性结肠炎。AnxA小鼠的临床和组织学参数比WT小鼠更严重，10mg/kg吡格列酮治疗仅使WT小鼠的疾病参数减轻。患病WT小鼠组织切片中AnxA1表达增加，与CD68巨噬细胞的存在呈正相关。患病WT小鼠结肠中金属蛋白酶-9（MMP-9）和无活性的33kDa AnxA1水平升高，吡格列酮治疗可使其降低。吡格列酮治疗可降低表达AnxA1的RAW 264.7巨噬细胞中脂多糖（LPS）处理引起的细胞因子分泌、活性氧生成和MMP-9表达，在AnxA1敲低的巨噬细胞中未检测到这些作用。吡格列酮治疗还可减弱LPS介导的RAW 264.7巨噬细胞中AnxA1裂解的增加。最后，吡格列酮治疗增加了表达AnxA1的RAW 264.7巨噬细胞中细胞外信号调节激酶（ERK）的磷酸化，但在AnxA1敲低的巨噬细胞中未增加。因此，我们的数据突出了AnxA1是吡格列酮对IBD治疗作用的关键因素。
