发酵麸皮多糖对大鼠空肠组织抗氧化能力、形态结构和紧密连接蛋白表达的影响

目的：研究发酵麸皮多糖对断奶大鼠空肠组织抗氧化能力、形态结构和紧密连接蛋白表达的影响。方法：将40 只雄性断奶Wistar大鼠随机分为5 组，包括对照组、VC组及发酵麸皮多糖低、中、高剂量组（每天分别灌服生理盐水、100 mg/kg mb VC及20、40、80 mg/kg mb发酵麸皮多糖，灌胃剂量均为0.4 mL），实验期为21 d。检测大鼠空肠组织中总抗氧化能力（total antioxitant capacity，T-AOC），过氧化氢酶（catalase，CAT）、超氧化物歧化酶（superoxide dismutase，SOD）、谷胱甘肽过氧化物酶（glutathione peroxidase，GSH-Px）活力以及谷胱甘肽（glutathione，GSH）、8-羟基脱氧鸟苷（8-hydroxy deoxyguanosine，8-OHdG）含量；采用苏木素-伊红染色法分析大鼠空肠测定绒毛高度和隐窝深度，计算绒毛高度与隐窝深度的比值；并采用实时荧光定量聚合酶链反应法测定空肠Claudin-1、Occludin和ZO-1 3 种紧密连接蛋白的mRNA表达量。结果：与对照组相比，灌胃40 mg/kg mb发酵麸皮多糖能显著提高断奶大鼠空肠组织中T-AOC、CAT、SOD和GSH-Px活力以及GSH含量（P＜0.05），显著降低8-OHdG含量（P＜0.05）；提高空肠绒毛高度和绒毛高度/隐窝深度，降低隐窝深度；提高Claudin-1、Occludin和ZO-1 3 种紧密连接蛋白的mRNA表达量。结论：发酵麸皮多糖可以改善断奶大鼠空肠抗氧化能力和形态结构，提高紧密连接蛋白的表达，起到保护肠道健康的作用。

Effects of Fermented Wheat Bran Polysaccharides on Antioxidant Capacity,Morphological Structure and Tight Junction Protein Expression in Rat Jejunum

This study was conducted to investigate the effects of oral supplementation with fermented wheat bran polysaccharides (FWBPs) on antioxidant capacity, morphological structure and tight junction protein expression in the jejunum of weaned rat pups. Forty healthy weaned Wistar rats with similar body mass were randomly assigned to five groups, including control (saline), VC (positive control, 100 mg/kg mb), and low-, medium- and high-dose FWBPs groups (20、40、80 mg/kg mb in a dosage of 0.4 mL). The experimental duration was 21 days. The total antioxidative capacity (T-AOC), catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities, and glutathione (GSH) and 8-hydroxydeoxyguanosine (8-OHdG) contents in jejunum were measured. Histopathological examination with hematoxylin and eosin (HE) staining was used to analyze villus height and crypt depth, and the ratio of villus height to crypt depth was calculated. The mRNA expression of the tight junction proteins Claudin-1, Occludin and zonula occludens-1 were determined using quantitative real-time polymerase chain reaction (qPCR). The results showed that oral administration of FWBPs at 40 mg/kg mb significantly improved T-AOC, CAT, SOD and GSH-Px activities and GSH content in jejunum (P < 0.05), and significantly decreased the content of 8-OHdG (P < 0.05). FWBPs increased the villus height and decreased crypt depth, thus resulting in increased villus height/crypt depth ratio. The mRNA expression of the tight junction proteins in the jejunum was significantly up-regulated in the FWBPs groups. In summary, fermented wheat bran polysaccharides can improve the antioxidant capacity and jejunal morphology and promote the expression of itght junction proteins, thereby preserving intestinal health in weaned rats.