Transcriptome profiling of Gastrocnemius from mice following supplementation with the combination of nicotinamide and pyridoxine (NAM/PN)

Nicotinamide and pyridoxine have been identified in an in vitro screening as potent modulators of Muscel Stem cell activity. To test the in vivo efficacy (of NAM/PN) on muscle regneration, we used a mouse model of muscle injury and regeneration. Transcriptomic analyses on whole muscles harvested 5 days after muscle injury were performed to better understand the effect of NAM/PN. Overall design: To induce a muscle injury (Day 0), cardiotoxin was injected into muscles from 1 leg. From Day 0, mice were daily treated by oral gavage either with NAM/PN or a matching placebo. At Day 5 after induction of muscle injury, mice were euthanized and muscle tissue were collected. Young and aged mice were used in this study. Gastrocnemius muscles from both legs (contralateral and injured) were used for transcriptomic analyses.

烟酰胺（Nicotinamide）与吡哆醇（pyridoxine）已通过体外筛选（in vitro screening）被鉴定为强效的肌肉干细胞（Muscle Stem Cell）活性调节剂。为验证NAM/PN对肌肉再生的体内功效（in vivo efficacy），我们采用了肌肉损伤与再生的小鼠模型。为更好地解析NAM/PN的作用效果，我们对肌肉损伤后5天收获的整块肌肉开展了转录组学分析（Transcriptomic analyses）。

整体实验设计：于第0天向小鼠单腿肌肉注射心脏毒素（cardiotoxin）以构建肌肉损伤模型；自第0天起，每日通过灌胃法（oral gavage）对小鼠分别给予NAM/PN或等量安慰剂。肌肉损伤诱导后第5天，对小鼠实施安乐死并收集肌肉组织。本研究同时使用了年轻小鼠与老年小鼠，取双侧下肢（健侧与损伤侧）的腓肠肌（Gastrocnemius muscles）组织进行转录组学分析。