Amelioration of Insulin Resistance in Rats Treated with Rice Bran Oil

Abstract

Background: insulin resistance (IR) is a pathological condition characterized by inadequate peripheral tissue metabolic response to circulating insulin. It plays pathophysiological role in type 2 diabetes mellitus (T2DM). High dosage of fructose in the diet (60 g/100 g diet) may induce insulin resistance accompanied by deleterious metabolic consequences including hyperglycemia and hyperinsulinemia. Rice bran oil (RBO), is a rich source of antioxidants especially γ-oryzanol, αtocopherols and tocotrienols which contribute to high oxidative stability, longer shelf life than other edible oils and high antioxidant property against free radicals. The present work was undertaken to study if the addition of rice bran oil in rat's diets ameliorate the insulin resistance. Materials and methods: to achieve this target, plasma fasting glucose, serum insulin and calculated HOMA-IR, which assesse the presence of insulin resistance, was evaluated. Serum lipid profile (cholesterol, triglycerides, high-density lipoprotein-cholesterol (HDL) and low-density lipoproteincholesterol (LDL) was also evaluated. In addition, the oxidative stress was assessed through hepatic malondialdehyd (MDA) as an oxidative biomarker and the antioxidant enzyme superoxide dismutase (SOD) was also estimated. Results: RBO ameliorated HOMA-IR, oxidative biomarker (MDA) and increased SOD activity. Conclusion: high fructose diet induced oxidative stress which lead to insulin resistance, this was ameliorated by addition of RBO.

Rice bran oil ameliorates hepatic insulin resistance by improving insulin signaling in fructose fed-rats

“…Diminishes in insulin level along with the reduction in glucose and HOMA-IR suggest that RBO acts as a hypoglycemic agent through improving insulin action rather than insulin secretion. These results agree with those of Abd elbast et al [11] and Abd El-Wahab et al [5], who recorded that addition of RBO to high fructose diet-fed rats, improves insulin resistance. The appreciable amount of oleic acid and tocotrienols in RBO may be the causes of glucose reduction and insulin sensitivity in rats fed HFD containing RBO [30,31].…”

“…These bioactive compounds reduce oxidative stress which causes many diseases such as diabetes, cancers, and neurodegenerative diseases [10]. Several studies have demonstrated that RBO possesses hypoglycemic activity [5,11] since chronic exposure to hyperglycemia may induce dysregulation of gene expression that converges on impaired insulin secretion and increased apoptosis [12].…”

Rice Bran Oil Improves Insulin Resistance by Affecting the Expression of Antioxidants and Lipid‐Regulatory Genes

“…Rice bran oil (RBO) is characterized by its mild flavor, high smoke point, and long shelf stability, in addition to its high content of linoleic and oleic fatty acids and natural antioxidants such as γ-oryzanol, phytosterols, tocopherols, and tocotrienols (Friedman, 2013;Liang et al, 2014). RBO was reported as a lipid-lowering agent (Abd Elbast, Rashed, Mohamed, Ahmed, & Ahmed, 2016;Berger et al, 2005), which protects against diabetes mellitus (Posuwan et al, 2013), cancers (Shih et al, 2011), brain aging, and neurodegenerative diseases (Stephanie et al, 2013) due to its antioxidant content.…”