Regenerative Neurogenesis After Ischemic Stroke Promoted by Nicotinamide Phosphoribosyltransferase–Nicotinamide Adenine Dinucleotide Cascade

Background and Purpose—Nicotinamide adenine dinucleotide (NAD) is a ubiquitous fundamental metabolite. Nicotinamide phosphoribosyltransferase (Nampt) is the rate-limiting enzyme for mammalian NAD salvage synthesis and has been shown to protect against acute ischemic stroke. In this study, we investigated the role of Nampt–NAD cascade in brain regeneration after ischemic stroke. Methods—Nampt transgenic (Nampt-Tg) mice and H247A mutant enzymatic-dead Nampt transgenic (ΔNampt-Tg) mice were subjected with experimental cerebral ischemia by middle cerebral artery occlusion. Activation of neural stem cells, neurogenesis, and neurological function recovery were measured. Besides, nicotinamide mononucleotide and NAD, two chemical enzymatic product of Nampt, were administrated in vivo and in vitro. Results—Compared with wild-type mice, Nampt-Tg mice showed enhanced number of neural stem cells, improved neural functional recovery, increased survival rate, and accelerated body weight gain after middle cerebral arter...