Protective action of saharian Anvillea radiata extracts against oxidative stress, inflammatory processes and diabetic neuropathy progression in high-fat-fed mice

Diabetic neuropathies are of the major and earliest complications in diabetes and are associated with reactive oxygen species (ROS) production and inflammation in neurons and glial cells. We recently reported the antioxidant and antidiabetic properties of water-soluble extracts of the traditional medicine Anvillea radiata Coss & Dur (AR). The present study investigated whether AR aqueous and n-butanol polyphenol-enriched extracts could afford protection against diabetic neuropathy. In the in vitro part of the study, antiglycative and ROS-producing enzymes inhibition capacities were demonstrated. In further experiments driven on AR-treated rat cell cultures, inflammation markers (TNFalpha, IL-6, IL-1)were measured in lipopolysaccharides-induced microglial cells and cytoprotection was evaluated on methylglyoxal-exposed astrocytes. In the in vivo part of the study, both extracts were given orally for 12 weeks at the dose of 75 mg/kg to high-fat-diet-C57BL/6J diabetic mice. Significant reduction of hyperglycemia and oxidative stress were observed, together with strong decrease of: i) thermal withdrawal latency (-30%) and T cells infiltration in sciatic nerve (-40%), ii) vasoconstriction, superoxide and protein carbonyls production in aortic rings, iii) myeloperoxidase and xanthine oxidase overactivation in plasma and kidney, iv) lipid peroxidation. Taken together, AR extracts may prove to be of therapeutic value in the management of diabetes complications