Vitamin B-Complex Mitigates Sub-Chronic Methamphetamine-Induced Oxidative Stress and Neurobehavioral Deficits in Adolescent Wistar Rats

Abstract

Methamphetamine (METH) abuse is a growing public health concern, particularly among Nigerian youths, where it is often consumed for its stimulant and euphoric effects but is associated with severe neurotoxic and psychiatric consequences. This study evaluated the neuroprotective potential of vitamin B-complex against METH-induced cerebellar and cerebral toxicity in adolescent male Wistar rats. Fifty-eight rats weighing 115–128 grams were used, with 28 employed for toxicity testing and 30 randomized into six experimental groups (n = 5). Group A (Negative Control) and received feed and distilled water only. Group B received 8 mg/kg of methamphetamine. Group C and D received 50 mg/kg and 100mg/kg of vitamin B-complex respectively. Group E received a co-administration of 8 mg/kg methamphetamine and 50 mg/kg of vitamin B-complex, while Group F received a co-administration of 8 mg/kg of methamphetamine and 100 mg/kg of vitamin B-complex. Treatments were administered orally for 28 days. Neurobehavioral evaluations (Morris water maze and hanging wire test) were conducted during days 24–28 to capture sub-chronic functional outcomes. At termination, animals were anesthetized, brains harvested, and tissues processed for biochemical and histological analysis. Results showed that METH-treated rats exhibited significant (p < 0.05) weight loss, prolonged escape latencies, impaired motor strength, increased lipid peroxidation, and reduced antioxidant markers (SOD, GSH), with histology revealing neuronal degeneration. In contrast, vitamin B-complex supplementation, alone or co-administered with METH, improved body weight, enhanced behavioral performance, normalized oxidative stress indices, and preserved cerebellar and cerebral histoarchitecture. These findings suggest that vitamin B-complex offers significant protection against METH-induced neurotoxicity, supporting its potential as an adjunctive therapeutic strategy for substance-related neurological disorders.