核桃低聚肽润肠通便功能作用

Effect of walnut oligopeptides on intestine-moistening and constipationrelieving in mice: an experimental research

目的探讨核桃低聚肽的润肠通便功能及机制,为核桃低聚肽应用于便秘治疗提供依据。方法成年雄性ICR小鼠随机分为6组:对照组、模型组、乳清蛋白组(440mg/kg)和3个核桃低聚肽组(220、440、880mg/kg),连续灌胃7d。以盐酸洛哌丁胺建立便秘模型,测定小鼠小肠的墨汁推进率,排出首粒黑便时间、3h/6h内排便粒数、粪便重量,小鼠血清P物质、血管活性肠肽、胃肠激素内毒素(ET)、生长抑素(SS)、胃动素(MTL)、胃泌素含量;苏木素-伊红染色观察小鼠小肠绒毛病理改变。结果与乳清蛋白组比较,高剂量核桃低聚肽组小鼠小肠墨汁推进率明显增加[(0.69±0.10)vs.(0.92±0.14)]、首粒黑便排出时间缩短[(272.60±24.83)vs.(241.50±29.88)min],6h内粪便粒数和粪便重量增加[排便粒数:(5.00±1.41)vs.(6.80±1.75)粒、排便重量:(0.06±0.02)vs.(0.12±0.03)g];与乳清蛋白组比较,高剂量核桃低聚肽组小鼠血清中ET、胃动素含量明显升高,生长抑素水平明显下降。结论核桃低聚肽具有润肠通便功能,其机制可能与核桃低聚肽促进小鼠血清中胃肠激素内毒素、胃动素表达,抑制生长抑素表达有关。

Objective To evaluate intestine-moistening and constipation-relieving effects of walnut (Juglans regia) oligopeptides in mice and to provide evidences for application of walnut oligopeptides in treatment of constipation. Methods Mice constipation model was established with gastric gavage of loperamide hydrochloride at dosages of 5 and 10 mg/kg body weight. Totally 120 ICR adult male mice were randomly assigned into two subgroups for observations of ink propulsion in small intestine and defecation after experiment and then the mice of each subgroup were randomly divided into a control group (with saline), a model group (with saline), a whey protein group (440 mg/kg bw), and 3 walnut oligopeptides groups (220, 440, and 880 mg/kg bw). All the treatments were performed by gastric gavage once a day continuously for 7 days. Sixteen hours after the last treatment, all the mice were gavaged with loperamide hydrochloride except for those of the control group and 30 minutes later with ink. The propulsion rate of ink in small intestine and the time for the first black fences granule discharge, the number, weight and water content of black feces granules were determined;the serum concentrations of substance P, vasoactive intestinal peptide, endothelin (ET), somatostatin (SS), motilin (MLT), gastrin were detected;and the length of small intestinal villus was measured. Results Compared with those of the whey protein group, the propulsion rate of ink in small intestine was significantly increased (0.92 ± 0.14 vs. 0.69 ± 0.10);the time for the first black feaces discharge was shortened (241.50 ± 29.88 vs. 272.60 ± 24.83 minutes);and the number and weight of feces granules were increased (number: 6.80 + 1.75 vs. 5.00 + 1.41;weight: 0.12 + 0.03 vs. 0.06 + 0.02 gram) in high dose walnut oligopeptides group. Futhermore, the serum concentration of ET and MTL were significantly increased, while the level of SS was significantly decreased in comparison with those of the whey protein group. Conclusion Walnut oligopeptides could promote intestine-moistening and constipation-relieving in mice and the mechanism of the effect may be related to upregulated serum expression of endotoxin, motilin and down-regulated expression of somatostatin.