con NR si intende il nicotinamide riboside, una forma di vit. B3 già studiata e dalle incredibili proprietà. E' tanto promettente che 5 premi nobel hanno recentemente reclamizzato un integratore anti-invecchiamento negli USA chiamato Elysium e basato proprio su questa sostanza. in pratica incrementa selettivamente il NAD+ un co-fattore coinvolto nel metabolismo, nel differenziamento e nel controllo della stabilità genomica (attraverso l'azione indiretta sulle sirtuine). Nel topo inverte (si badi, non si parla di prevenzione né di mantenimento ma di inversione) l'invecchiamento del sistema muscolo-scheletrico. Ebbene secondo un recente articolo apparso su Science preverrbbe anche l'incanutimento. eccovi i riferimenti:
H. Zhang et al. NAD+ repletion improves mitochondrial and stem cell function and enhances life span in micce#65532;, Science (2016)
NR attenuates senescence of neural stem cells and melanocyte stem cells and increases mouse lifespan. Aging is accompanied by a decline in the number and function of neural stem cells (NSCs) (23) and melanocyte stem cells (McSCs) (41). Therefore, to examine the generalized importance of NAD+ homeostasis in somatic SCs, we assessed the effect of NR in NSCs from aged mice. NR increased proliferation as shown by 5-ethynyl-2-deoxyuridine (EdU) and antigen Ki-67 (Ki67) staining, and induced neurogenesis indicated by doublecortin (DCX) staining, in both the subventricular zone (SVZ) (Fig. 6, A to D) and the dentate gyrus (DG) of the hippocampus (fig. S6, A to D) in aged mice. Nicotinamide mononucleotide (NMN), another NAD+ precursor, also has beneficial effects in aged neural stem cells (23).
Similarly, NR rescued the decline of McSCs in hair follicles of aged mice, as reflected by increases in mast/stem cell growth factor receptor Kit (c-KIT) and short transient receptor potential channel 2 (TRP2), known McSCs markers, in NR-treated aged mice (Fig. 6, E and F). NR treatment of C57BL/6J mice slightly increased lifespan (chow diet, mean 829 ± 12.0; NR, mean 868 ± 12.4 days, p = 0.034) (Fig. 6G). The beneficial effect of NR on survival was further confirmed by Cox proportional hazards analysis (Fig. 6H). Although the lifespan benefit is small, it was obtained with the NR treatment commencing late in life at 24 months. This argues that aging, in part, may stem from the dysregulation of general SC NAD+ homeostasis.