Drug-induced Intestinal Mucosal Injury / 胃肠病学

Drug-induced intestinal mucosal injury is a commonly seen adverse event with the exposure to various drugs. During the course of drug therapy, when exacerbation of primary gastrointestinal disease or new onset of gastro-intestinal symptoms occurs, drug-induced injury should be considered. Patients should be evaluated by gastrointestinal endoscopy for confirming the diagnosis. In this article, the etiologic and pathogenic factors, as well as the diagnostic and therapeutic approaches of four commonly seen drug-induced intestinal mucosal injuries, which were caused by nonsteroidal anti-inflammatory drugs, chemotherapeutic agents, immune checkpoint inhibitors and antibiotics were reviewed.

Effects of antagonistic peptides binding specifically with first and second extracellular loops of CCR5 on colitis rats induced by TNBS / 中国病理生理杂志

AIM:To study the effects of antagonistic peptides binding specifically with the first and second extracellular loops (ECL1 and ECL2) of C-C chemokine receptor 5 (CCR5) on the colitis rats induced by trinitrobenzenesulfonic acid (TNBS) and the mechanisms.METHODS:The colitis model of SD rats was induced by TNBS (100 mg/kg).The effects of 2 antagonistic peptides at different doses (ECL1:25, 35 and 45 mg/kg;ECL2:15, 25 and 35 mg/kg) on the model rats including the changes of disease activity index (DAI), colon macroscopic damage index (CMDI) and histological grading were observed.The mRNA and protein expression levels of TNF-α and COX-2 in the colonic mucosa were detected by real-time PCR and Western blot, respectively.RESULTS:Compared with model group, the changes of DAI, CMDI and histopathological injury of the rats treated with ECL2 antagonistic peptide HY at an appropriate dose were significantly reduced (P<0.05), and the protein and mRNA expression levels of TNF-α and COX-2 were significantly decreased (P<0.05).However, the effects of ECL1 antagonistic peptide GH on all scores and the expression levels of TNF-α and COX-2 were not obvious.CONCLUSION:ECL2 antagonistic peptide HY relieves TNBS-induced colitis in SD rats via down-regulating the expressions of TNF-α and COX-2 in the colonic mucosa, while the effect of ECL1 antagonist peptide GH was not obvious.

Correlation of CCR5 expression with β-arrestin 2 expression in colonic mucosa of patients with inflammatory bowel disease / 中国病理生理杂志

AIM:To analyze the expression of CCR5 and correlation with the expression ofβ-arrestin 2 in the intestinal mucosa of the patients with inflammatory bowel disease ( IBD) , so as to study the role of CCR5 andβ-arrestin 2 in the pathogenesis of IBD.METHODS:Paraffin sections of the colonic mucosa were prepared from 53 patients with active IBD, 26 patients with remissive IBD and 30 healthy people.Immunohistochemical EnVision two-step method was used to test the expression of CCR5 andβ-arrestin 2 in the biopsic intestinal mucosa.RESULTS:The positive rate, strongly posi-tive rate and immunohistochemical score of CCR5 expression in active IBD were significantly higher than those in normal controls or remissive IBD (P<0.05).No correlation of CCR5 expression with clinical severity, lesion distribution, and endoscopic grade in active IBD was observed.The expression ofβ-arrestin 2 was significantly lower in active IBD than that in the remissive IBD and normal controls, and there was a negative correlation ofβ-arrestin 2 expression with CCR5 expres-sion (P<0.05).CONCLUSION:The expression of CCR5 is higher, and expression ofβ-arrestin 2 is lower, and there is a negative correlation of expression of CCR5 with expression ofβ-arrestin 2 in intestinal mucosa of the active IBD.

Panning and identification of antagonistic active peptides specifically bin-ding to the first and second extracellular membrane loops of rat CCR5 by technique of phage display peptide library / 中国病理生理杂志

[ ABSTRACT] AIM: To pan the active peptides which specifically bound to the first and second extracellular membrane loops of rat CC chemokine receptor 5 ( CCR5 ) .METHODS: The technique of phage display peptide library was used and binding ability of the peptides was identified.The amino acid sequences of the first and second extracellular loops of rat CCR5 were searched in the protein database and chemically synthesized corresponding linear peptides were used as targets in the biopanning.After 3 to 4 rounds of screening with Ph.D.TM-7 Phage Display Peptide Library were per-formed, the specific phages were collected and primarily identified by ELISA.RESULTS:The sequences of the peptides displayed on the selected phages were GHWKVWL and HYIDFRW, both of them exhibited positive in phage binding ELISA and the binding to phages and targets were concentration dependent and saturable.CONCLUSION:Two antagonis-tic active peptides specifically binding to CCR5 were successfully obtained by the technique of phage display peptide librar-y, and the binding ability to the first and second extracellular membrane loops of rat CCR5 were proved in vitro.