Adjei A A, Morioka T, Ameho C K, Yamauchi K, Kulkarni A D, Al-Mansouri H M, Kawajiri A, Yamamoto S
Department of Bacteriology, University of the Ryukyus, Okinawa, Japan.
Gut. 1996 Sep;39(3):428-33. doi: 10.1136/gut.39.3.428.
Growing evidence suggests that intestinal recovery from injury induced by radiation, endotoxin, and protein deficiency is improved by the ingestion of nucleosides and nucleotides.
This study examined the effect of dietary nucleosides and nucleotides supplementation on trinitrobenzene sulphonic acid induced colonic damage in experimental colitis.
Sprague-Dawley rats were randomised into two groups and fed nucleic acid free 20% casein diet (control) or this diet supplemented with 0.5% nucleoside-nucleotide mixture for four weeks. On the second week, colonic inflammation was induced in rats by intracolonic administration of 0.25 ml of 50% ethanol containing 25 mg of trinitrobenzene sulphonic acid. Additionally, other sets of rats were treated with 0.25 ml of 50% ethanol, 25 mg of trinitrobenzene sulphonic acid in 0.25 ml saline, or 0.25 ml of 0.9% saline.
After two weeks, colon weight, macroscopic and microscopic damage scores, were significantly greater (p < 0.05) in the nucleoside-nucleotide supplemented group compared with the non-supplemented control groups. The same variables seen in the trinitrobenzene sulphonic acid-ethanol group fed nucleoside-nucleotide free diet were greater (p < 0.05) than in the rest of the groups fed nucleoside-nucleotide free diet and treated with ethanol, trinitrobenzene sulphonic acid in saline, or saline. Histologically, segmental ulceration and inflammation associated with significantly increased infiltration of polymorphonuclear leucocytes, macrophages, lymphocytes, fibroblasts were observed in the supplemented group compared with the controls. In the nucleoside-nucleotide supplemented group the epithelial damage, mucosal erosion, oedema, and coagulative necrosis of the muscularis propria was more extensive in comparison to the non-supplemented control groups.
This study suggests that dietary nucleosides and nucleotides may aggravate colonic damage and inflammation in chemically induced experimental colitis in rats; and that nucleoside-nucleotide free diet combined with other pharmacological agents may offer a better response.
越来越多的证据表明，摄入核苷和核苷酸可促进肠道从辐射、内毒素和蛋白质缺乏所致损伤中恢复。
本研究探讨膳食补充核苷和核苷酸对三硝基苯磺酸诱导的实验性结肠炎结肠损伤的影响。
将Sprague-Dawley大鼠随机分为两组，分别喂食无核酸的20%酪蛋白饮食（对照组）或添加0.5%核苷-核苷酸混合物的该饮食，持续四周。在第二周，通过结肠内给予0.25 ml含25 mg三硝基苯磺酸的50%乙醇诱导大鼠结肠炎症。此外，其他几组大鼠分别接受0.25 ml 50%乙醇、0.25 ml盐水中含25 mg三硝基苯磺酸或0.25 ml 0.9%盐水处理。
两周后，补充核苷-核苷酸组的结肠重量、宏观和微观损伤评分显著高于未补充的对照组（p < 0.05）。喂食无核苷-核苷酸饮食的三硝基苯磺酸-乙醇组的相同变量高于喂食无核苷-核苷酸饮食并接受乙醇、盐水中三硝基苯磺酸或盐水处理的其他组（p < 0.05）。组织学上，与对照组相比，补充组观察到节段性溃疡和炎症，伴有多形核白细胞、巨噬细胞、淋巴细胞、成纤维细胞浸润显著增加。与未补充的对照组相比，补充核苷-核苷酸组的上皮损伤、黏膜糜烂、水肿和固有肌层凝固性坏死更广泛。
本研究表明，膳食核苷和核苷酸可能会加重化学诱导的大鼠实验性结肠炎的结肠损伤和炎症；无核苷-核苷酸饮食与其他药物联合使用可能会有更好的效果。
