Antidiabetic Efficacy of Diosmetin-Loaded Phytosomes in STZ-Induced Diabetic Rats

Abstract

Diabetes mellitus is a long-standing metabolic disorder characterized by hyperglycemia and disturbed carbohydrate, lipid, and protein metabolism due to impaired insulin secretion or peripheral insulin resistance. A flavonoid, diosmetin, possesses excellent biological activities but is limited in clinical use because it has poor aqueous solubility, low permeability, and significant first-pass metabolism, which leads to low oral bioavailability. To overcome these limitations, a phytosomatically formulated diosmetin was designed to maximize its bioavailability and antidiabetic effects. The current research involves the successful loading of diosmetin (DS) into a phytosomal entity by the formation of bond between the soya phosphatidylcholine and diosmetin in various molar ratios. Successfully prepared DS phytosomes through complexation with phospholipids and they were characterized by physicochemical, chromatography, spectroscopy, differential scanning calorimetry (DSC), and nuclear magnetic resonance (NMR) studies. In vivo studies using streptozotocin which induced diabetes in albino rats, and compared the results against pure DS alone. The antidiabetic potential of DS phytosomes evaluated by an in vivo study revealed a significant decrease in the levels of blood glucose in the DS phytosomes-treated group as compared to plain DS. The above-mentioned results showed that the antidiabetic potency of DS was enhanced in phytosomes as compared to DS.

This research points to phytosomal encapsulation as a powerful approach to enhance the solubility, bioavailability and therapeutic interest of diosmetin and presents a worthy method for the improvement in pharmacokinetics in other poorly soluble flavonoids.