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Objective:
Stress can lead to various changes in the gastrointestinal tract of rats. The present study was designed to compare the effect of palm vitamin E (PVE) and α-tocopherol (α-TF) supplementations on the gastric parameters important in maintaining gastric mucosal integrity in rats exposed to water immersion restraint stress (WRS). These parameters include gastric acidity, plasma gastrin level, gastric prostaglandin E2 (PGE2), and gastric lesions.Materials and Methods:
Sixty male Sprague-Dawley rats (200-250 g) were divided into three equal groups: a control group, which received a normal rat diet (RC), and two treatment groups, receiving oral supplementation of either PVE or α-TF at 60 mg/kg body weight for 28 days. Each group was further divided into two groups: the nonstress and stress groups. The stress groups were subjected to 3.5 h of WRS once at the end of the treatment period. Blood samples were then taken to measure the gastrin level, after which the rats were killed. Gastric juice was collected for measurement of gastric acidity and gastric tissue was taken for measurement of gastric mucosal lesions and PGE2.Results:
Exposure to stress resulted in the production of gastric lesions. PVE and α-TF lowered the lesion indices as compared to the stress control group. Stress reduced gastric acidity but pretreatment with PVE and α-TF prevented this reduction. The gastrin levels in the stress group were lower as compared to that in the nonstress control. However, following treatment with PVE and α-TF, gastrin levels increased and approached the normal level. There was also a significant reduction in the gastric PGE2 content with stress exposure, but this reduction was blocked with treatment with both PVE and α-TF.Conclusion:
In conclusion, WRS leads to a reduction in the gastric acidity, gastrin level, and gastric PGE2 level and there is increased formation of gastric lesions. Supplementation with either PVE or α-TF reduces the formation of gastric lesions, possibly by blocking the changes in the gastric acidity, gastrin, and gastric PGE2 induced by stress. No significant difference between PVE and α-TF was observed. 相似文献Methods: In a randomized double-blind placebo-controlled clinical trial, 46 patients with RA were assigned to one of two groups; patients in the probiotic group received a daily capsule containing 108 colony forming units (CFUs) of Lactobacillus casei 01 (L. casei 01), while those in the placebo group took identical capsules containing maltodextrin, for 8 weeks. In the baseline and at the end of the study, anxiety, physical activity levels, and dietary intakes were assessed. Anthropometric parameters, serum malondialdehyde (MDA), total antioxidant capacity (TAC), erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activities were measured.
Results: There was no significant difference between the two groups for demographic characteristics, anthropometric parameters, physical activity, anxiety levels, or dietary intakes, throughout the course of the study. No significant within- and between-group differences were observed for MDA, TAC, or CAT. SOD activity decreased only in the probiotic group and GPx activity decreased in both study groups (p < 0.05); however, no significant between-group difference was found for these enzymes activities at the end of the study (p > 0.05).
Conclusion: No significant effect of L. casei 01 supplementation was observed on the oxidative status of patients with RA, compared to placebo. 相似文献