Oakmoss Exhibits Antihyperglycemic Activity in Streptozotocin-Induced Diabetic Rats

Aims: The study aimed to assess the antidiabetic effect of oakmoss. Background: Lichens species are dual organisms consisting of a mycobiont (Fungi) and a photoautotrophic partner (Algae). They are widely used in traditional medicine as a treatment for diabetes. Objective: This study was designed to assess the antihyperglycemic activity as well as the antihyperlipidemic capacity of oakmoss (Evernia prunastri (L.)) in normal and streptozotocin(STZ)- induced diabetic rats. Methods: This study has evaluated the effects of aqueous extract of oakmoss at a dose of 60 mg/kg on blood glucose levels and lipid profile in normal and STZ-induced diabetic rats. Histopathological examination of the liver, determination of glycogen content in liver and skeletal muscles (EDL and soleus), antioxidant activity, and phytochemical investigation were also performed. Results: Both single and repeated oral doses of oakmoss (60 mg/kg) significantly reduced blood glucose, triglycerides, and very-low-density lipoprotein (VLDL) levels in diabetic rats. Furthermore, repeated oral administration of oakmoss for 7 days ameliorated the liver function by increasing its glycogen content and improving its histological architecture in treated diabetic rats. In addition, the aqueous extract of oakmoss exhibited antioxidant activity and showed richness in certain phytochemicals, especially in phenolic acids and flavonoids. Conclusion: Oakmoss, a lichen species, exhibits a potential effect on improving hyperglycemia and hypertriglyceridemia in diabetic rats.