Neuroprotective effects of dexpanthenol on streptozotocin-induced neuronal damage in rats.

AIM Although the most common age-related neurodegenerative disease defined by memory loss is Alzheimer's disease (AD), only symptomatic therapies are present. A complex pathway for the AD pathogenesis that includes an increase in inflammation has recently been suggested. Since in previous animal experiments dexpanthenol has anti-inflammatory and neuroprotective activities, effects and role of dexpanthenol in an intracerebroventricular (ICV)-streptozotocin (STZ) induced sporadic-AD(memory impairment) animal model have been examined. DESIGN AND METHODS In total, 18 adult sprague-dawley rats were classified into 3 groups; control (n = 6), STZ + Saline (n = 6) and STZ + Dexpanthenol (n = 6). Twelve AD-induced rats through STZ-injection (3 mg/kg) into both lateral ventricles via stereotaxy were separated into two groups five days after STZ administration: one of these groups was treated with dexpanthenol (1000 mg/kg/day, i.p.) for 3 weeks and the other with saline. A passive avoidance learning (PAL) test was used after treatment, followed by brain tissue extraction in all subjects. Brain levels of tumor necrosis factor-alpha (TNF-α) and choline acetyl transferase (ChAT) were measured and Cresyl violet staining was used to count neurons in cornu ammonis-1 (CA1) and cornu ammonis-3 (CA3). RESULTS It was observed that ICV-STZ significantly shortened PAL latency, increased levels of TNF-α in brain, decreased activity of ChAT in brain, and number of hippocampal neurons. However, dexpanthenol significantly reduced all of those STZ-induced harmful effects. CONCLUSION Dexpanthenol significantly prevented the memory deficit induced by ICV-STZ through mitigating neuronal loss in hippocampus, cholinergic deficiency and neuroinflammation in rats. These findings suggest that dexpanthenol may be beneficial for treating memory impairment.