Caffeine mitigates ROS accumulation and attenuates motor neuron degeneration in the wobbler mouse model of amyotrophic lateral sclerosis.

Abstract

Background: Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease characterized by oxidative stress and progressive motor neuron degeneration. This study evaluates the potential neuroprotective effects of caffeine in the Wobbler mouse, an established model of ALS.

Methods: Wobbler mice received caffeine supplementation (60 mg/kg/day) via drinking water, and key parameters, including muscle strength, NAD metabolism, oxidative stress, and motor neuron morphology, were assessed at critical disease stages.

Results: Caffeine delayed motor performance decline, as observed in grip strength tests during the early symptomatic phase. Histological analyses revealed that significantly fewer motor neurons were lost in caffeine-treated mice at p41, despite no changes in soma morphology. Biochemical assays demonstrated that caffeine significantly reduced ROS levels and restored NAD levels to wildtype-like values, although NMNAT2 protein expression remained unaffected. The data suggest that caffeine mitigates oxidative stress through alternative pathways, potentially involving enhanced mitochondrial function and antioxidative defenses.

Conclusions: These findings highlight the potential of caffeine as a protective agent for delaying motor neuron degeneration in ALS. Future studies should explore optimal dosing strategies, combinatorial treatment approaches, and the underlying molecular mechanisms, to enable translation of these findings to human ALS patients.