Voluntary wheel running combined with low-dose lithium supplementation improves novel object recognition in male DBA/2 J mdx mice.

BACKGROUND: Duchenne muscular dystrophy (DMD) is a severe neuromuscular disorder caused by a mutation to the dystrophin gene. Cognitive dysfunction is a lesser-known symptom of DMD; however, approximately one-third of patients experience it. Though the mechanisms underlying these dysfunctions are unknown, research points towards an Alzheimer's disease (AD)-like pathology in clinical and preclinical work. In a recent study, we previously demonstrated that inhibiting glycogen synthase kinase 3 (GSK3) through a combination of low-dose lithium supplementation and voluntary wheel running (VWR) improved muscle quality and function in the mdx mouse model of DMD. Interestingly, both VWR and GSK3 inhibition with lithium can exert neuroprotective effects against Alzheimer's pathology; however, whether this treatment can also benefit cognitive function in mdx mice remains unknown.

METHODS: Here, we conducted a brief follow-up study to determine whether inhibiting GSK3 with a combination of low-dose lithium supplementation and VWR would enhance novel object recognition in mdx mice, while also investigating potential mechanisms, including beta-secretase activity, Tau phosphorylation, and sarco(endo)plasmic reticulum calcium ATPase (SERCA) activity.

RESULTS: Our findings show that lithium and VWR treatment, on average, improved novel object recognition in mdx mice-a result that may be linked to enhanced SERCA activity within the hippocampus but not to any changes in beta-secretase activity or tau phosphorylation.

CONCLUSION: Taken together, these data point to the potential benefits of Li and VWR on cognitive function in mdx mice, highlighting the need for future research aimed at teasing out the potential mechanisms.