Effect of red beetroot juice on oxidative status and islet insulin release in adult male rats

• Published in: Diabetology and metabolic syndrome 2022-04, Vol.14 (1), p.58-58, Article 58
• Main Authors: Sayyar, Armin, Oladi, Mohammad, Hosseini, Mehran, Nakhaee, Samaneh, Ataie, Zomorrod, Farrokhfall, Khadijeh
• Format: Article
• Language: English
• Subjects: Animals; Antioxidants; Aorta; Aspartate; Aspartate transaminase; Beetroot; Bioavailability; Blood glucose; Blood pressure; Blood sugar; Carbohydrate metabolism; Diabetes; Drinking water; Ethylenediaminetetraacetic acid; Fruit juices; Glucose; Glucose metabolism; Glucose tolerance; Glucose tolerance tests; Heart; Hematology; Hypertension; Insulin; Insulin resistance; Insulin secretion; Islet insulin secretion; Lipid peroxidation; Lipids; Liver; Malondialdehyde; Medical research; Medicine, Experimental; Metabolic syndrome; Metabolites; Nitrates; Nitric oxide; Peroxidation; Physiological aspects; Secretion; Transaminase
• ISSN: 1758-5996; 1758-5996
• DOI: 10.1186/s13098-022-00830-z

Beetroot is rich in inorganic nitrate and it has been shown that inorganic nitrate has beneficial effects on metabolic syndrome. This study aims to investigate the effect of red beetroot juice (RBJ) on carbohydrate metabolism in adult insulin-resistant rats. Sixteen male Wistar rats (32 weeks old) were divided into two equal groups: control and RBJ. Treatment with drinking water (control) and 100% RBJ (RBJ) was lasted for 5 weeks. At the end of the 4th week the intraperitoneal glucose tolerance test was performed and at the end of the study period animals were sacrificed and blood and tissue (aorta, heart, and liver) samples were collected. Furthermore, pancreatic islets were isolated and their insulin secretion activity was investigated in different glycemic conditions. Compared to the control group, RBJ-treated rats showed lower blood glucose and insulin levels in the glucose tolerance test. Serum and tissue levels of nitric oxide in the RBJ group were significantly higher than those in the control group. The liver peroxidation and serum aspartate transaminase levels were significantly increased in the RBJ-treated animals compared to the control group. The islets of RBJ group exhibited lower insulin secretion, especially in 16.7 mM glucose concentration (supraphysiologic condition) than control group. RBJ consumption improves glucose metabolism in rats via increasing nitric oxide metabolites in an insulin-independent manner. However, future studies are needed to minimize the potential hepatic adverse consequences.