In vitro and ex vivo anti-diabetic and anti-hyperglycemic properties of Zataria multiflora essential oil.

The underlying mechanism involved in the onset of many diseases such as diabetes is oxidative stress. Zataria multiflora has a very high antioxidant power that can be used in the antioxidant therapy of the diabetes symptom. The in vitro antioxidant and anti-diabetic capacity of Zataria multiflora essential oil (ZMEO) incorporated in dendrosome against glucose oxidation, lipid oxidation, protein oxidation, and protein glycation was analyzed. The ex vivo antioxidant capacity of dendrosomal ZMEO were explored against hyperglycemia (HG)-induced oxidative stress. Inhibition of oxidative stress markers; NADH oxidase (NOX), nuclear respiratory factor 2 (NRF2) and nuclear factor kappa B (NF-kB) were examined. Dendrosomal-ZMEO displayed low conductivity, low surface tension, low zeta-potential, nanoscale particle size and low viscosity that suggest dendrosomal-ZMEO could remain stable in biological fluids. FTIR spectra of dendrosomal-ZMEO indicated the non-covalent interactions between dendrosome and ZMEO and the entrapment of ZMEO droplets in the dendrosome network. Dendrosomal-ZMEO displayed good anti-glucose oxidation, anti-lipid peroxidation, anti-protein oxidation, and anti-protein glycation activity. Dendrosomal ZMEO strongly reduced intracellular hydrogen peroxide and NOX expression and activity in HG-treated macrophages while increased superoxide dismutase (SOD) and catalase (CAT) expression and activity in a synergistic manner. HG-treated murine macrophages showed an increased level of NF-kB expression while the decreased level of NRF2 expression compared to controls. The anti-diabetic activity of ZMEO by sequestering hydrogen peroxide and down-regulation of NOX activity is a recommended mechanism for diabetes and oxidative stress. The effect of ZMEO on decreasing NF-kB and increasing in NRF2, transcription factors involved in oxidative stress and hyperglycemia, may imply its clinical application.