Effects of Nicotinamide Mononucleotide (NMN) on Kidney Function
NMN supplementation may have both protective and potentially harmful effects on kidney function, with evidence suggesting age-dependent responses that require careful consideration before use.
Potential Beneficial Effects of NMN on Kidneys
NMN administration has demonstrated protective effects against renal interstitial fibrosis following acute kidney injury (AKI) by reducing tubular cell DNA damage, cellular senescence, and inflammation in experimental models 1
NMN may help repair kidney damage by boosting nicotinamide adenine dinucleotide (NAD+) levels, which are important for DNA repair mechanisms and metabolic function in renal tubular cells 1, 2
In human proximal tubular cells, NMN has shown the ability to reduce hydrogen peroxide and hypoxia-induced DNA damage and subsequent cellular senescence 1
The reduced form of NMN (NMNH) has demonstrated even more potent effects in increasing NAD+ levels and accelerating repair in renal tubular epithelial cells following hypoxia/reoxygenation injury 2
Potential Risks and Age-Dependent Concerns
Recent research indicates that NMN supplementation may have age-dependent effects on kidney function, with potentially harmful effects in older individuals 3
In aged mice (26-month-old), but not young mice, NMN supplementation (300 mg/kg/day) increased expression of genetic markers of inflammation (IL-1-beta and Ccl2) and tubular injury (Kim-1) 3
NMN-treated aged mice showed higher circulating levels of uremic toxins compared to either aged controls or young NMN-treated mice, suggesting that pre-existing mitochondrial dysfunction in aged kidneys may make them susceptible to inflammatory responses with NMN supplementation 3
Clinical Safety Data in Humans
Clinical trials have demonstrated that oral administration of NMN at 250 mg/day for 12 weeks in healthy subjects caused no abnormalities in physiological and laboratory tests, with no obvious adverse effects observed 4
Intravenous administration of NMN in healthy volunteers did not negatively affect metabolic markers in the kidneys, liver, heart, or pancreas, suggesting safety in this limited context 5
NMN administration significantly increased blood NAD+ levels and reduced blood triglyceride levels in healthy individuals, which could potentially benefit metabolic health 5
Considerations for Kidney Health and Protein Intake
For individuals with chronic kidney disease (CKD), the American Diabetes Association recommends reducing protein intake to 0.8-1.0 g/kg body weight/day in earlier stages of CKD and to 0.8 g/kg body weight/day in later stages to improve measures of renal function 6
Medical nutrition therapy that favorably affects cardiovascular risk factors may also have beneficial effects on microvascular complications including nephropathy 6
In individuals with diabetes and microalbuminuria, reducing protein intake has been associated with slowing the decline in renal function 6
Recommendations for NMN Use Considering Kidney Health
Individuals with pre-existing kidney disease should exercise caution when considering NMN supplementation, particularly older adults, due to potential age-dependent inflammatory responses 3
Those considering NMN supplementation should have baseline kidney function testing and regular monitoring if they choose to use this supplement, especially if they have risk factors for kidney disease 6
The safety profile of NMN appears better in younger, healthy individuals compared to older populations with potential mitochondrial dysfunction 3
If using NMN supplements, starting with lower doses and monitoring for any changes in kidney function would be a prudent approach 4, 5
Conclusion
While NMN shows promise for kidney protection in certain contexts, particularly in acute kidney injury models, the age-dependent effects raise concerns about its use in older populations. The contrasting effects between young and aged kidneys highlight the need for personalized approaches to NAD+ precursor supplementation based on age and pre-existing kidney function.
Human Medical Consultant Note: The evidence regarding NMN's effects on kidneys is still emerging, with animal studies showing both protective and potentially harmful effects depending on age and pre-existing conditions. More clinical research is needed to establish definitive guidelines for NMN use in different populations, particularly those with kidney disease or advanced age.