Hydroxytyrosol attenuates peripheral neuropathy in streptozotocin-induced diabetes in rats.

Peripheral neuropathy is one of the most frequent and severe complications of diabetes. Hydroxytyrosol (HT), the major antioxidant polyphenolic compound of olive oil, has been investigated as a new potential treatment to counteract the progression of peripheral diabetic neuropathy in rats. An established model of streptozotocin-induced diabetes has been used. After confirmation of hyperglycemia, diabetic and nondiabetic animals were randomized to receive either a low dose or a high dose of HT, or the corresponding vehicle, for 6 weeks. At the end of the 6-week period of treatment, HT blunted plasma thiobarbituric acid-reactive substances increase (p < 0.05) and significantly reduced nerve conduction velocity (p < 0.05) and thermal nociception impairment in diabetic rats (p < 0.05). Sciatic nerve Na(+), K(+)-ATPase activity reduction was also abolished by HT (p < 0.05). The present study provides evidence of the therapeutic potential of the natural substance hydroxytyrosol in the early stage of diabetic neuropathy.