Nicotinamide Riboside Enhances Mitochondrial Bioenergetics and Dopaminergic Signaling in a Double-Hit Parkinson's Model
نيكوتيناميد ريبيوزايد يحسن الحيوية الميتوكوندرية والإشارات الدوبامينية في نموذج باركنسون مزدوج الضربة
Journal: Research square
University: unknown
Study Type: animal
Evidence Level: preliminary
Published:
⚠️ Warning: This is a preliminary study (animal/cell) and has not been proven in humans.
30-Second Summary
In a double-hit PD mouse model combining A53T α-synuclein overexpression with chronic benomyl exposure, nicotinamide riboside (NR) supplementation improved mitochondrial bioenergetics and dopaminergic signaling. Importantly, these effects occurred without changes in dopaminergic neuron survival.
1-Minute Summary
This preclinical study used a double-hit PD mouse model (A53T α-synuclein overexpression with benomyl exposure). NR supplementation in drinking water enhanced mitochondrial bioenergetics and dopaminergic signaling in the substantia nigra pars compacta. Notably, these functional improvements occurred without altering dopaminergic neuron survival. The findings provide preliminary evidence that NR may modulate neuronal function via mitochondrial pathways under PD-like stress, independent of neuron loss.
3-Minute Summary
Parkinson’s disease is characterized by progressive loss of substantia nigra pars compacta dopaminergic neurons and motor dysfunction, with mitochondrial failure and aging as critical contributors. Nicotinamide riboside (NR), a dietary NAD+ precursor, has been proposed to support cellular energy and mitochondrial health, but translational potential in PD remains uncertain. In this study, researchers used a double‑hit mouse model that combines A53T α‑synuclein overexpression in SNc DA neurons with chronic dietary exposure to benomyl, an environmental mitochondrial stressor. Mice received NR in drinking water throughout the study period. Motor behavior was tracked longitudinally, and analyses focused on mitochondrial bioenergetics within SNc DA neurons as well as measures of dopaminergic signaling. The results indicate that NR supplementation markedly enhances mitochondrial bioenergetics in the targeted neurons. Separately, NR treatment was associated with improved dopaminergic signaling, even though SNc dopaminergic neuron survival was not rescued by NR in this model. In other words, NR may confer functional improvement by boosting energy availability and signaling capacity without altering the underlying neuronal loss induced by the double hit. These findings suggest that metabolic interventions aimed at NAD+ metabolism and mitochondrial function may modulate neuronal physiology under PD‑like stress. However, translation to humans remains uncertain and work is needed to define dose and duration.
Full Analysis
This study sits at the intersection of PD pathophysiology and mitochondrial biology, employing a double-hit PD model to explore NR’s potential neurometabolic benefits. Strengths include a biologically relevant model that combines a genetic synucleinopathy (A53T α-synuclein) with chronic environmental mitochondrial stress (benomyl exposure), creating a convergence of factors that plausibly mimic aspects of PD risk. The continuous NR administration in drinking water provides a straightforward, translational delivery route. The focus on SNc dopaminergic neurons aligns with PD’s most clinically relevant cell population, and the assessment of mitochondrial bioenergetics alongside dopaminergic signaling addresses both cellular energy and network output. The key finding—NR enhances mitochondrial bioenergetics in SNc DA neurons and improves dopaminergic signaling without rescuing neuron survival—suggests functional benefits may be achieved via metabolic and signaling pathways independent of neuroprotection. Mechanistically, NR as an NAD+ precursor could boost mitochondrial respiration, sirtuin activity, and energy metabolism, thereby supporting neuronal function under stress. Limitations include the use of a single mouse model with a specific toxin and a defined genetic alteration, which may limit generalizability to idiopathic PD. The dosing regimen, duration, sex differences, and long-term safety of NR require further study. Translation to humans remains speculative, and clinical relevance will depend on replication across models and careful dose optimization.Health Implications
Preclinical findings suggest NR may support cellular energy and dopaminergic signaling in PD-like stress, but do not imply PD prevention or reversal in humans. If future trials confirm safety and reproducibility, NR could be considered as part of a broader approach to support mitochondrial health, alongside lifestyle measures. Readers should consult healthcare providers before using dietary supplements, especially when managing neurodegenerative risk.
Key Findings
- NR supplementation enhanced mitochondrial bioenergetics in SNc dopaminergic neurons.
- NR improved dopaminergic signaling independently of dopaminergic neuron survival.