PMP22 and Charcot-Marie-Tooth disease type 1A: By modulating the activity of signaling proteins acting upstream of the Pmp22 gene, ascorbic acid, a specific antioxidant, had an inhibitory effect on adenylate cyclase activity and reduced the production of intracellular cAMP, improving motor function in a CMT1A rat model, but its clinical efficacy is not obvious [3,73].