NMN, vascular function and oxidative stress in aged mice

A study of blood vessels in aged mice

This article discusses research into whether NMN supplementation could affect age-associated vascular dysfunction and oxidative stress in mice. The proposed mechanism involved NAD+ availability and the activity of the NAD+-dependent enzyme SIRT1.

The research concerns an animal model. It does not establish that an NMN supplement reverses vascular aging or prevents cardiovascular disease in people.

Why NAD+ and SIRT1 were investigated

Blood-vessel function depends in part on the endothelium, the layer of cells lining the vessel. Excess oxidative stress can interfere with nitric-oxide signaling and contribute to impaired vessel dilation. Changes in the structural proteins of large arteries can also affect their stiffness.

Earlier research connected SIRT1 with aspects of vascular function and some of the responses observed during calorie restriction. This provided a rationale for investigating an NAD+ precursor as a way to influence related mechanisms in an experimental setting.

What the investigators reported

The cited study reported that NMN supplementation improved measures of vascular function in aged mice and reduced vascular oxidative stress. The archive also discusses changes in NAD+ availability, antioxidant-related activity and SIRT1 activity as possible parts of that response.

These findings describe measured outcomes under the conditions of the experiment. They should not be expanded into a claim that every organ becomes younger, that all age-associated disorders are prevented, or that a manufacturing specification guarantees a similar result.

Calorie restriction as a research comparison

Studies of calorie restriction have helped researchers investigate biological processes associated with aging. However, observing some overlapping pathways does not make NMN supplementation equivalent to calorie restriction or exercise. It also does not provide a basis for recommending a restrictive diet to an individual reader.

The practical question raised by the research is whether interventions targeting these pathways could eventually be evaluated for relevant clinical outcomes. That requires appropriately designed human studies, including assessments of benefits, adverse effects and duration of use.

What this paper does not show

The article's central evidence is from mice. Improvement in an experimental vascular measurement is not the same as a reduction in heart attacks, strokes or mortality in people. The study was not a clinical trial of a finished GAAH product.

Cited paper: Nicotinamide mononucleotide supplementation reverses vascular dysfunction and oxidative stress with aging in mice. DOI: 10.1111/acel.12461.