Dunaliella salina Attenuates Diabetic Neuropathy Induced by STZ in Rats: Involvement of Thioredoxin.

Diabetic neuropathy (DN) is a widespread disabling disorder including peripheral nerves' damage. The aim of the current study was to estimate the potential ameliorative effect of Dunaliella salina (D. salina) on DN and the involvement of the thioredoxin. Diabetes was induced by streptozotocin (STZ; 50 mg/kg; i.p). Glimepiride (0.5 mg/kg) or D. salina powder (100 or 200 mg/kg) were given orally, after 2 days of STZ injection for 4 weeks. Glucose, total antioxidant capacity (TAC), superoxide dismutase (SOD), and catalase (CAT) serum levels as well as brain contents of thioredoxin (Trx), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) were measured with the histopathological study. STZ-induced DN resulted in a significant (P < 0.05) rise in glucose blood level and brain contents of TNF-α and IL-6 and produced a reduction in serum TAC, SOD, CAT, and brain Trx levels with irregular islets of Langerhans cells and loss of brain Purkinje cells. Treatment with glimepiride or both doses of D. salina alleviated these biochemical and histological parameters as compared to the STZ group. D. salina has a neurotherapeutic effect against DN via its inhibitory effect on inflammatory mediators and oxidative stress molecules with its upregulation of Trx activity.