Diabetes mellitus (DM) is a chronic, lifelong condition threatening human health. Rosmarinus officinalis oil (RO) could have a future role in DM therapy. This study evaluated the composition and antioxidative potential of RO. Antidiabetic traits of RO in streptozotocin (STZ)‐induced diabetic rats was also studied considering the ameliorative impact against embryogenesis defects using in vitro and in vivo biochemical, histological, and genetic assays. RO was investigated for fatty acids and bioactive compounds (tocols and total phenolic compounds), and antiradical potential against DPPH• radicals. The genetic effects were investigated using comet assay and DNA fragmentation test. DM was induced to albino rats by injecting 60 mg/kg of STZ, while RO (100 mg/kg b.w.) was administered. The pregnant animals were divided into four groups; control (C), RO‐treated (RO), diabetic (D), and combined diabetic with RO‐treated (D‐RO). The study was conducted for 180 days. In RO, the contents of polyunsaturated fatty acids, monounsaturated fatty acids, and saturated fatty acids were 42.3%, 41.7%, and 15.8%, respectively. The levels of α‐, β‐, γ‐, and δ‐tocopherols were 280, 20, 1,025, and 35 mg/100 g RO, respectively. RO contained 7.2 mg GAE/g of total phenolic compounds (TPC), while RO quenched 70% of DPPH• radicals. While glucose levels reached the highest in DM rats, treating STZ‐induced diabetic animals with RO‐resoluted serum glucose levels. RO reduced the highest levels of serum chemistry parameters were recorded in DM animals. Histological photographs of maternal and fetus liver exhibited degenerated hepatic cells and congestion central vein. Comet cells and DNA fragments were significantly decreased in D‐RO group comparing to the DM group. RO exhibited antidiabetic capabilities, and thus, it could be utilized as a functional ingredient in novel foods, nutraceuticals, and dietary supplements for diabetic patients.
Practical applications
RO is rich in bioactive phytochemicals (tocols and phenolic compounds) with antiradical and antihyperglycemic capabilities. Tocols and phenolics are active in radical scavenging of reactive nitrogen species (i.e., peroxynitrite and nitrogen dioxide), and in the prevention of DNA bases nitration. Our results demonstrated that RO could improve the disturbed metabolism of carbohydrate in STZ‐diabetic animals. The potential mode of action of bioactive compounds in RO most likely encompasses the intracellular pathway involved in glucose homeostasis or insulin signaling. In addition, the suppression of oxidative stress by phenolic compounds could provide to the antidiabetic impacts of RO. Our data supported that RO could be utilized to ameliorate DM. Protection with RO directed high protection of the maternal organs and offspring against the oxidative stress of diabetes due to the antihyperlipidemic effects and the antioxidant capabilities of RO.