Department Of Pharmacology

Permanent URI for this communityhttps://kr.cup.edu.in/handle/32116/108

Browse

Author: search.filters.author.Tikoo, Kulbhushan

Search Results

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    L-Methionine supplementation attenuates high-fat fructose diet-induced non-alcoholic steatohepatitis by modulating lipid metabolism, fibrosis, and inflammation in rats
    (Royal Society of Chemistry, 2022-03-31T00:00:00) Navik, Umashanker; Sheth, Vaibhav G.; Sharma, Nisha; Tikoo, Kulbhushan
    Recently, the protective effects of a methionine-rich diet on hepatic oxidative stress and fibrosis have been suggested but not adequately studied. We, therefore, hypothesized that l-methionine supplementation would ameliorate the progression of hepatic injury in a diet-induced non-alcoholic steatohepatitis (NASH) model and aimed to investigate the underlying mechanism. NASH was developed in male Sprague Dawley rats by feeding them with a high-fat-fructose diet (HFFrD) for 10 weeks. The results demonstrated that l-methionine supplementation to NASH rats for 16 weeks improved the glycemic, lipid, and liver function profiles in NASH rats. Histological analysis of liver tissue revealed a remarkable improvement in the three classical lesions of NASH: steatosis, inflammation, and ballooning. Besides, l-methionine supplementation ameliorated the HFFrD-induced enhanced lipogenesis and lipid peroxidation. An anti-inflammatory effect of l-methionine was also observed through the inhibition of the release of proinflammatory cytokines. Furthermore, the hepatic SIRT1/AMPK signaling pathway was associated with the beneficial effects of l-methionine. This study demonstrates that l-methionine supplementation in HFFrD-fed rats improves their liver pathology via regulation of lipogenesis, inflammation, and the SIRT1/AMPK pathway, thus encouraging its clinical evaluation for the treatment of NASH. � 2022 The Royal Society of Chemistry.
  • No Thumbnail Available
    Item
    L-Methionine prevents ?-cell damage by modulating the expression of Arx, MafA and regulation of FOXO1 in type 1 diabetic rats
    (Elsevier GmbH, 2021-12-03T00:00:00) Navik, Umashanker; Rawat, Kajal; Tikoo, Kulbhushan
    L-Methionine (L-Met) is an essential sulphur-containing amino acid having a vital role in various key cellular processes. Here we investigated the effect of L-Met on streptozotocin-induced ?-cell damage model of diabetes mellitus in Sprague Dawley rats. At the end of study biochemical parameters, immunoblotting, qRT-PCR and ChIP-qPCR are performed. L-Met was administered orally (250 and 500 mg/kg/day) to diabetic animals for 8 weeks improved plasma glucose and insulin levels. Pancreas immunohistochemistry showed significant increase in insulin expression, decrease in glucagon and Bax expression. Interestingly, L-Met inhibited the expression of Arx; upregulated MafA and FOXO1 which play a critical role in the maintenance of ?-cell identity. Our data also showed a decrease in H3K27me3 and an increase in H3K4me3 (�bivalent domain� alteration) in diabetic rats and these recovered by L-Met. Furthermore, the chromatin-immunoprecipitation assay showed a decreased enrichment of H3K27me3 on the promoter of the FOXO1 gene in diabetic rats and L-Met prevents this decrease. Our results showed the first evidence of the involvement of H3K27me3 in regulating the expression of the FOXO1 gene and the prevention of ?-cell injury by L-Met treatment. In conclusion, we report the involvement of L-Met in the modulation of ?-cell identity marker (Arx), ?-cell identity marker (MafA) and regulation of FOXO1 by histone methylation marks for the first time. We are of the opinion that this employed as a novel therapeutic approach for mitigating diabetes-induced ?-cell death. � 2021 Elsevier GmbH
  • No Thumbnail Available
    Item
    Methionine as a double-edged sword in health and disease: Current perspective and future challenges
    (Elsevier Ireland Ltd, 2021-10-25T00:00:00) Navik, Umashanker; Sheth, Vaibhav G.; Khurana, Amit; Jawalekar, Snehal Sainath; Allawadhi, Prince; Gaddam, Ravinder Reddy; Bhatti, Jasvinder Singh; Tikoo, Kulbhushan
    Methionine is one of the essential amino acids and plays a vital role in various cellular processes. Reports advocate that methionine restriction and supplementation provide promising outcomes, and its regulation is critical for maintaining a healthy life. Dietary methionine restriction in houseflies and rodents has been proven to extend lifespan. Contrary to these findings, long-term dietary restriction of methionine leads to adverse events such as bone-related disorders, stunted growth, and hyperhomocysteinemia. Conversely, dietary supplementation of methionine improves hepatic steatosis, insulin resistance, inflammation, fibrosis, and bone health. However, a high level of methionine intake shows adverse effects such as hyperhomocysteinemia, reduced body weight, and increased cholesterol levels. Therefore, dietary methionine in a safe dose could have medicinal values. Hence, this review is aimed to provide a snapshot of the dietary role and regulation of methionine in the modulation of health and age-related diseases. � 2021 Elsevier B.V.