发酵麦麸多糖对氧化应激大鼠脾脏的保护作用研究

Protective Effects of Fermented Wheat Bran Polysaccharides against Oxidative Stress Induced by Diquat of Spleen in Weaned Rats

本试验旨在研究发酵麦麸多糖(fermented wheat bran polysaccharides,FWBPs)的体外抗氧化能力,并探究其对敌草快诱导的大鼠脾脏氧化应激是否有缓解作用。体外试验测定还原力、DPPH自由基及羟基自由基清除率。体内试验选取断奶雄性大鼠48只,按照随机分组原则,分为正常对照组(生理盐水)、氧化应激模型组(生理盐水)、 FWBPs低剂量组(100 mg/kg BW)、 FWBPs中剂量组(200 mg/kg BW)、 FWBPs高剂量组(400 mg/kg BW)和阳性对照组(100 mg/kg BW VC),每组8只,持续灌胃14 d。最后一次灌胃2 h后,除正常对照组外,其它五组腹腔注射敌草快(0.1 mmol/kg BW)建立氧化应激模型。24 h后屠宰,采集脾脏组织,测定脾脏组织抗氧化相关指标,利用RT-PCR技术分析抗氧化相关基因的m RNA表达量。结果表明:4 mg/mL FWBPs对DPPH自由基及羟基自由基的饱和清除率分别为92.35%和33.30%;敌草快攻毒会显著降低大鼠脾脏谷胱甘肽过氧化物酶(Glutathione peroxidase,GSH-Px)活力(P<0.05),显著增加总抗氧化能力(Total antioxitant capacity,T-AOC)、谷氨酸-半胱氨酸连接酶调节亚基(Glutamate cysteine ligase modifiersubunit,GCLM)的m RNA表达水平及8-羟基脱氧鸟苷(8-hydroxy deoxyguanosine,8-OHdG)的含量(P<0.05)。与氧化应激模型组相比,低、中剂量组大鼠脾脏中GSH-Px活性显著增加(P<0.05);低剂量组大鼠脾脏中谷胱甘肽(Glutathione,GSH)含量显著增加(P<0.05);中剂量组大鼠脾脏中醌氧化还原酶1(NAD(P)-Hquinoneoxidoreductase 1,NQO1)和核因子E2相关因子2(Nuclear factor E2-related factor 2,Nrf2)的mRNA表达量显著增加(P<0.05);而中、高剂量组和阳性对照组中8-OHdG含量显著降低(P<0.05)。FWBPs有较强的抗氧化能力,并可缓解大鼠脾脏组织氧化应激。

This study was conducted to measure antioxidant capacity of fermented wheat bran polysaccharides(FWBPs) in vitro and its antioxidative potential against diquat-induced oxidative stress of spleen of rats. The reducing power, DPPH radical and hydroxyl radical scavenging rate of FWBPs were determined. Forty-eight healthy weaned Wistar rats were randomly assigned to six groups with 8 rats in each group. The rats in low dose group, middle dose group and high dose group were orally treated with FWBPs at 100, 200 and 400 mg/kg BW, respectively, in positive control group were orally treated with vitamin C at 100 mg/kg BW, in normal group and toxic group were orally treated with equal volume saline for 14 days. After the last gavage for 2 hours, except the normal control group, the other five groups were intraperitoneally injected with diquat(0.1 mmol/kg BW) to establish the oxidative stress model. After challenged 24 h, the spleen tissues were collected to measure antioxidant indices by ELISA kits. The mRNA expression of antioxidant related genes was determined using RT-PCR. The results showed that the saturation scavenging rates of FWBPs to DPPH radical and hydroxylradical reached 92.35% and 33.30%, respectively. Diquat treatment significantly decreased the activities of glutathione peroxidase(GSH-Px)(P<0.05), while increased total antioxidative capacity(T-AOC), 8-hydroxy deoxyguanosine(8-OHdG) contents, and the mRNA expression of glutamate cysteine ligase modifiersubunit(GCLM) in the spleen tissues of rats(P<0.05). Under the oxidative stress, the activities of GSH-Px increased in the low and middle dose group(P<0.05);the glutathione(GSH) contents increased in the low dose group(P<0.05);the mRNA expression of NAD(P)-Hquinoneoxidoreductase 1(NQO1) and nuclear factor E2-related factor 2(Nrf2) increased in the middle dose group(P<0.05);while 8-OHdG contents decreased in the middle, high dose group and positive group(P<0.05). In summary, FWBPs exerted strong antioxidant effect against oxidative stress induced by diquat of spleen in rats.