Figure 1: The 21.5 kDa phosphorylated MBP (P-MBP) levels were closely related to the myelination status. Aging-induced demyelination and its improvement by different constituents of NYT were accompanied by the specific disappearance and reappearance of 21.5 kDa P-MBP protein, respectively. The levels of the 21.5-, 18.5-, 17- and 14-kDa isoforms (21.5, 18.5, 17 and 14) of total MBPs and P-MBP were quantified using an immunoblot analysis of isolated myelin sheaths. Because the basal levels of P-MBPs and MBPs fluctuate during aging, the quantitative ratio of the four isoforms was calculated for each age. The quantification and statistical analyses were performed as described in the ‘Materials and Methods’ section. Data represent the mean ± SEM (n = 3). *P < .005 versus untreated (3 months of water alone), #P < .05 versus untreated. a: Mixture A (Keihi, Onji, Shakuyaku Kazo, Chinpi); b: Mixture B (Keihi, Shakuyaku); c: Mixture C (Onji, Kanzo); d: Mixture D (Chinpi).