Modulatory effect of concomitant administration of sitagliptin and vitamin E on inflammatory biomarkers in rats fed with high fat diet: role of adiponectin

High-fat diet-induced memory impairment and anxiety-like behavior in rats attenuated by peel extract of Ananas comosus fruit via atheroprotective, antioxidant and anti-inflammatory actions

BACKGROUND

Pineapple peel is a waste component of pineapple with valuable source of metabolites as phytoactive compounds in ameliorating metabolic-related disorders. This study investigated the atheroprotective and neuroprotective effects of peel extract of Ananas comosus fruit (PEAC) in normal diet (ND) and high-fat diet (HFD) fed rats.

METHODS

Male Wistar rats were fed ND or HFD for 9 weeks, and beginning from the 6th week animals were also orally treated with PEAC (200 mg/kg). Memory performance was assessed using Y-maze test (YMT) and novel object recognition test (NORT) while anxiolytic-like effect was assessed on the elevated plus maze (EPM). Serum cholesterol, triglycerides and HDL-C were determined, while LDL-C and atherogenic risk calculated. Serum and brain tissue malondialdehyde, reduced glutathione, catalase were determined. Brain acetylcholinesterase activity and interleukin-6 level were also determined.

RESULTS

PEAC significantly attenuated HFD-induced reduction in correct alternation in YMT, and discrimination index in NORT. Also, PEAC demonstrated anxiolytic-like activity in EPM test. PEAC significantly improved lipid profile and decreased risk of atherogenicity in ND and HFD-fed rats. In addition, PEAC improves serum and brain antioxidant status by decreasing malondialdehyde and increasing GSH and catalase. PEAC significantly impaired HFD-induced brain acetylcholinesterase activity and IL-6 levels.

CONCLUSION

These findings suggest that peel extract of Ananas comosus fruit may protect against diet-induced behavioral disturbances via atheroprotective, antioxidants and anti-inflammatory activities.

Intestinal Alkaline Phosphatase Combined with Voluntary Physical Activity Alleviates Experimental Colitis in Obese Mice. Involvement of Oxidative Stress, Myokines, Adipokines and Proinflammatory Biomarkers

Intestinal alkaline phosphatase (IAP) is an essential mucosal defense factor involved in the process of maintenance of gut homeostasis. We determined the effect of moderate exercise (voluntary wheel running) with or without treatment with IAP on the course of experimental murine 2,4,6-trinitrobenzenesulfonic acid (TNBS) colitis by assessing disease activity index (DAI), colonic blood flow (CBF), plasma myokine irisin levels and the colonic and adipose tissue expression of proinflammatory cytokines, markers of oxidative stress (SOD2, GPx) and adipokines in mice fed a standard diet (SD) or high-fat diet (HFD). Macroscopic and microscopic colitis in sedentary SD mice was accompanied by a significant decrease in CBF, and a significant increase in the colonic expression of tumor necrosis factor-alpha (TNF-α), IL-6, IL-1β and leptin mRNAs and decrease in the mRNA expression of adiponectin. These effects were aggravated in sedentary HFD mice but reduced in exercising animals, potentiated by concomitant treatment with IAP, especially in obese mice. Exercising HFD mice demonstrated a substantial increase in the mRNA for adiponectin and a decrease in mRNA leptin expression in intestinal mucosa and mesenteric fat as compared to sedentary animals. The expression of SOD2 and GPx mRNAs was significantly decreased in adipose tissue in HFD mice, but these effects were reversed in exercising mice with IAP administration. Our study shows for the first time that the combination of voluntary exercise and oral IAP treatment synergistically favored healing of intestinal inflammation, strengthened the antioxidant defense and ameliorated the course of experimental colitis; thus, IAP may represent a novel adjuvant therapy to alleviate inflammatory bowel disease (IBD) in humans.