morin and Chronic-Disease

Hyperglycemia associated ER stress has been found as a critical contributor in the pathogenesis of type 2 diabetes mellitus. However, reports regarding molecular mechanisms involved are limited. This study was aimed to identify the role of ER stress in regulating hepatic glucose metabolism and its link with oxidative stress. Further, this study explores the novel role of Morin, a flavonol, in modulating ER stress in STZ/nicotinamide induced type 2 diabetic male Wistar rats. Results demonstrate that hyperglycemia induced ER stress in rats and significantly lowered the expression of glucose transporter proteins resulting in impaired glucose metabolism during diabetes. Morin was found to downregulate PERK-eIF2α-ATF4 pathway by interacting with PERK protein as confirmed through pull-down assay. Additionally, Morin maintained the reducing environment in ER and enhanced PDI activity compared to diabetic rats. Morin prevented cell death by suppressing the expression of PERK dependent pro-apoptotic proteins including ATF4 and CHOP. Findings from this study affirm the role of ER stress in hyperglycemia induced gluco-metabolic aberrations and liver injury as confirmed by ISRIB, a standard chemical ER stress inhibitor. Notably, Morin promoted deactivation of UPR sensors and upregulated PDI activity endorsing its anti-ER stress potential which may allow the development of new therapeutic avenues to target hyperglycemic hepatotoxicity.

Topics: Activating Transcription Factor 4; Animals; Antioxidants; Apoptosis; Chronic Disease; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Down-Regulation; eIF-2 Kinase; Endoplasmic Reticulum Stress; Flavonoids; Hyperglycemia; Liver Diseases; Male; Rats; Rats, Wistar; Streptozocin

Morin, a bioflavonoid with antioxidant properties, shows intestinal anti-inflammatory activity in the acute phase of the trinitrobenzenesulphonic acid model of rat colitis.. To assess the anti-inflammatory activity of morin in the chronic stages of trinitrobenzenesulphonic acid-induced rat colitis.. Rats were rendered colitic by a single colonic instillation of 30 mg of the hapten trinitrobenzenesulphonic acid dissolved in 0.25 mL of 50% ethanol. A group of colitic animals was given morin orally at doses of 25 mg/kg daily. Animals were sacrificed every week for 4 weeks. Colonic damage was evaluated macroscopically and microscopically. Different biochemical markers of colonic inflammation were also assayed, including myeloperoxidase activity, leukotriene B4 and interleukin-1beta synthesis, glutathione and malonyldialdehyde levels and nitric oxide synthase activity.. The administration of morin facilitated tissue recovery during the 4 weeks following colonic insult with trinitrobenzenesulphonic acid, as demonstrated macroscopically and microscopically, as well as biochemically by a reduction in myeloperoxidase activity. The intestinal anti-inflammatory effect of morin was accompanied by a significant reduction in colonic leukotriene B4 and interleukin-1beta levels, improvement in colonic oxidative stress and inhibition of colonic nitric oxide synthase activity.. Morin exerts a beneficial anti-inflammatory effect in the chronic phase of trinitrobenzenesulphonic acid-induced rat colitis through the down-regulation of some of the mediators involved in the intestinal inflammatory response, including free radicals, cytokines, leukotriene B4 and nitric oxide.

Topics: Administration, Oral; Animals; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Chronic Disease; Colitis; Disease Models, Animal; Female; Flavonoids; Interleukin-1; Intestinal Mucosa; Leukotriene B4; Nitric Oxide; Nitric Oxide Synthase; Peroxidase; Rats; Rats, Wistar; Trinitrobenzenesulfonic Acid