Nigella sativa L. oil ameliorates insulin resistance caused by dexamethasone treatment in male Wistar rats

Alli-oluwafuyi, Abdul-Musawwir; Amin, Abdulbasit; Abdulmajeed, Wahab Imam; Imam, Aminu; Niyi-odumosu, Faatihah; Abdulraheem, Haleemat; Gwadabe, Saadiyat; Biliaminu, Abayomi Sikiru

Abstract

Dexamethasone is an anti-inflammatory glucocorticoid that may alter glucose and lipid homeostasis
depending on the dose and/or duration of administration. Nigella sativa oil (NSO) can be used as
potential modulator of intermediary glucose and lipid metabolism. Herein, the authors evaluated the
dose-dependent effects of NSO (0.2 and 0.4 ml/kg body weight) supplementation on plasma glucose,
insulin and triglyceride concentration in rats treated with dexamethasone (1 mg/kg body weight) for 5
days. Adult male Wistar rats (150 to 200 g) were housed and treated in the animal holding facility of the
Faculty of Basic Medical Sciences, University of Ilorin, Ilorin. Animals were randomly distributed into 4
groups: control (normal saline, 1 ml/kg), DEX (dexamethasone 1 mg/kg), DEX + NSO 0.2 ml/kg and DEX+
NSO 0.4 ml/kg. All drugs were administered intraperitoneally. To assess insulin resistance, an insulin
tolerance test was performed in addition to fasting glucose and insulin measurements used in
calculating the homeostatic model assessment of insulin resistance index (HOMA-IR). Insulin-induced
glucose lowering was improved following NSO supplementation during the insulin tolerance test
(p<0.05). Likewise, there was a reduction in fasting hyperinsulinemia (50%; p<0.05) and HOMA-IR index.
Dexamethasone induced hypertriglyceridemia which was not significantly reduced following NSO
supplementation. Furthermore, NSO had no significant effect on liver alanine aminotransferase enzyme
activity in rats treated with dexamethasone. In conclusion, it is shown that 5 days therapy with
dexamethasone can be used as a model of insulin resistance and NSO supplementation for 5
consecutive days attenuates hyperglycemia and insulin resistance induced by dexamethasone
treatment

• Journal Article Type: Article
• Acceptance Date: Jan 13, 2017
• Online Publication Date: Mar 25, 2017
• Publication Date: 2017-03
• Deposit Date: Aug 18, 2022
• Publicly Available Date: Aug 19, 2022
• Journal: African Journal of Pharmacy and Pharmacology
• Electronic ISSN: 1996-0816
• Peer Reviewed: Peer Reviewed
• Volume: 11
• Issue: 11
• Article Number: 5EA640263744
• Pages: 144-151
• DOI: https://doi.org/10.5897/ajpp2016.4705
• Keywords: Pharmaceutical Science; Pharmacology
• Public URL: https://uwe-repository.worktribe.com/output/9887094
• Publisher URL: https://academicjournals.org/journal/AJPP/article-full-text-pdf/5EA640263744