[Mutation of mitochondrial DNA in patients with non-alcoholic steatohepatitis]

When the numbers of mutations per 1,000 bases of mitochondrial DNA were compared among three groups of Al-Hep, NASH and FL, there were significantly more mutations in ND1 and COII of Al-Hep and NASH than in FL. When details of the base mutation were investigated by group, the transition type of mutation between T:A and C:G occurred in control and coding regions. In FLS and FLS-ob mice, mutations in the D-loop and coding regions of mitochondrial DNA were investigated by sequencing analysis. The average number of mutations per clone in each region was more than 5-fold higher in FLS-ob than in FLS. In addition, the mutations were mostly transition-type mutations. These data indicate that nitric oxide plays an important role in mitochondrial DNA mutations.