Lambertini Carlotta, Zannoni Augusta, Romagnoli Noemi, Bombardi Cristiano, Morini Maria, Dondi Francesco, Bernardini Chiara, Forni Monica, Rinnovati Riccardo, Spadari Alessandro
Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy.
Front Vet Sci. 2020 Nov 27;7:589367. doi: 10.3389/fvets.2020.589367. eCollection 2020.
Large colon volvulus in horses is associated with a poor prognosis, especially when ischemic-reperfusion injury of the affected intestinal tract develops. Proteinase-activated receptor 2 (PAR) plays an important role in the pathogenesis of inflammation in the gastrointestinal tract. The aim of this study was to evaluate the distribution and expression of PAR in colonic pelvic flexure of horses spontaneously affected by large colon volvulus (CVH group). Eight horses admitted for severe abdominal colon volvolus and which underwent surgery were included. Colon samples were collected after enterotomy. Data previously obtained from healthy horses were used as a control group. Histologic evaluation was carried out to grade the severity of the colon lesions. Immunofluorescence, western blot and quantitative polymerase chain reaction (RT-qPCR) were carried out on colon samples to evaluate PAR expression. In addition, the transcriptional profile of cytokines and chemokines was evaluated using RT Profiler™ PCR Array Horse Cytokines & Chemokines. Three out of the eight patients were euthanised due to clinical deterioration. Immunostaining for PAR was observed in the enterocytes, intestinal glands and neurons of the submucosal and myenteric plexi. In the CVH horses, the expression of PAR mesenger RNA (mRNA) did not differ significantly from that of the healthy animals; western blots of the mucosa of the colon tracts showed a clear band of the expected molecular weight for PAR (~44 kDa) and a band smaller than the expected molecular weight for PAR (25kDa), suggesting its activation. The gene expressions for C-X-C motif ligand 1 (CXCL1); interleukin 8 (IL8), macrophage inflammatory protein 2 beta (MIP-2BETA) were upregulated in the colic horses as compared with the colons of the healthy horses. Therefore, in the present study, the expression and activation of PAR in the colons of horses in the presence of an inflammatory reaction like that occurring in those with spontaneous colon volvulus was confirmed.
马的大结肠扭转预后不良，尤其是在受影响的肠道发生缺血再灌注损伤时。蛋白酶激活受体2（PAR）在胃肠道炎症的发病机制中起重要作用。本研究的目的是评估PAR在自发发生大结肠扭转的马的结肠骨盆曲中的分布和表达（CVH组）。纳入了8匹因严重腹部结肠扭转入院并接受手术的马。在肠切开术后收集结肠样本。以前从健康马获得的数据用作对照组。进行组织学评估以对结肠病变的严重程度进行分级。对结肠样本进行免疫荧光、蛋白质印迹和定量聚合酶链反应（RT-qPCR）以评估PAR表达。此外，使用RT Profiler™ PCR Array Horse Cytokines & Chemokines评估细胞因子和趋化因子的转录谱。8例患者中有3例因临床恶化而实施安乐死。在肠上皮细胞、肠腺以及黏膜下和肌间神经丛的神经元中观察到PAR免疫染色。在CVH马中，PAR信使核糖核酸（mRNA）的表达与健康动物相比无显著差异；结肠黏膜的蛋白质印迹显示出一条PAR预期分子量（约44 kDa）的清晰条带和一条小于PAR预期分子量（25 kDa）的条带，表明其被激活。与健康马的结肠相比，绞痛马中C-X-C基序配体1（CXCL1）、白细胞介素8（IL8）、巨噬细胞炎性蛋白2β（MIP-2BETA）的基因表达上调。因此，在本研究中，证实了在存在像自发结肠扭转患者那样的炎症反应时马结肠中PAR的表达和激活。
