Effects of high-intensity interval training and Acetyl-L-carnitine on spatial memory in male rat model of Parkinson's disease

Abstract

Parkinson's disease is a neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra region of the brain, resulting in memory impairment. Regular exercise has been shown to modulate oxidative stress, reduce brain damage, enhance hippocampal neurogenesis, and improve spatial memory. Acetyl-L-carnitine, known for its protective and antioxidant properties, can enhance brain function. This study aimed to investigate the combined effects of High-Intensity Interval Training (HIIT) and acetyl-L-carnitine supplementation on substantia nigra tissue in a rat model of Parkinson's disease induced by 6-hydroxydopamine. A total of 36 male rats, weighing 270±20 grams, were randomly divided into six equal groups: healthy control, surgical sham, parkinsonian (unilateral single injection of 6-hydroxydopamine in the substantia nigra at 12.5 µg/ml), parkinsonian receiving HIIT (8 weeks, 5 sessions per week), parkinsonian receiving acetyl-L-carnitine (100 mg/kg daily for 8 weeks by gavage), and parkinsonian receiving acetyl-L-carnitine + HIIT (similar regimen as groups 4 and 5). Spatial memory was evaluated using the Morris water maze test, and after euthanasia, brain tissue was collected to assess pathological changes in the hippocampus. Data were analyzed with a significance level of p<0.05, employing SPSS 23 software. Parkinson's disease induction resulted in reduced spatial memory indices (p<0.05). HIIT and acetyl-L-carnitine supplementation significantly improved spatial memory factors (p<0.05). Statistically, the combined HIIT and acetyl-L-carnitine treatment demonstrated the most substantial improvement in spatial memory indices. The pathological results were consistent with the results of spatial memory. This study suggests that concurrent HIIT and acetyl-L-carnitine treatment can enhance spatial memory and ameliorate pathological changes in the hippocampus of Parkinson's disease rats.

Keywords

• acetyl-l-carnitine
• high intensity interval training (hiit)
• parkinson's disease
• spatial memory.