Effects of chronic liver diseases on mitochondrial DNA transcription and replication in human liver

To evaluate the effects of chronic liver diseases on mitochondrial DNA (mtD NA) transcription and replication, nuclear respiratory factor-1 (NRF-1) mRN A, mitochondrial transcription factor A (mtTFA) mRNA, a RNA component of ri bonuclease (RNase) for mitochondrial RNA processing (MRP), mitochondrial cy tochrome b mRNA, and mtDNA were measured in normal, chronically viral-hepat itic and cirrhotic human livers. The mRNA levels of the regulatory factors for mitochondrial gene (NRF-1 and mtTFA) and cytochrome b were significantl y increased by chronic hepatitis (160, 280, and 175 %, respectively) compar ed with those in normal livers, but were not different between cirrhotic an d normal livers. On the other hand, concentrations of mtDNA and RNA compone nt of RNase MRP were not different among normal, chronically hepatitic, and cirrhotic livers. These results suggest that either persistent hepatitis v iral infection or repeated cell necrosis and regeneration in chronically he patitic liver may be associated with increase in mtDNA transcription.