To the Editor: We read the article by Chihara N et al. entitled “mitochondrial DNA alterations in colorectal cancer cell lines” with great interest. In this article, authors aimed to find potential roles of mtDNA alterations in colorectal cancers. In order to show mtDNA alteration, they sequenced entire mtDNA of eleven human-derived colorectal carcinoma cell lines. Many point mutations were det...

background: mitochondria are autonomous cellular organelles that oversee a variety of functions such as metabolism, energy production, calcium buffering, and cell fate determination. most recently, mitochondrial dysfunction caused by mitochondrial mutations played important roles in the pathogenesis of asthma. however, the frequency of mitochondrial trna mutations in asthma is largely unknown. ...

Primary cardiomyopathy is an important cause of mortality in children and adults. Apart from inherited disorders of myocardial contractile and structural proteins, several defects of energy metabolism may cause cardiomyopathy. Most of the energy required for myocardial contraction is derived from aerobic metabolism. Faulty aerobic metabolism involving the heart may be due to defects of mitochon...

Mutations of thymidine kinase 2 (TK2), an essential component of the mitochondrial nucleotide salvage pathway, can give rise to mitochondrial DNA (mtDNA) depletion syndromes (MDS). These clinically heterogeneous disorders are characterized by severe reduction in mtDNA copy number in affected tissues and are associated with progressive myopathy, hepatopathy and/or encephalopathy, depending in pa...

We evaluated oxygen consumption rates in human cells cultured in the presence of a nucleoside analog reverse transcriptase inhibitor (NRTI) cocktail that inhibits mitochondrial DNA synthesis. We treated a proliferating human lymphocyte cell line and a primary culture of human adipose cells with antiretroviral drugs (AZT+ddC+d4T). The effects of these drugs on mitochondrial DNA (mtDNA) levels an...

Isolated Complex I (CI) deficiency, the most frequent cause of mitochondrial disease, is a clinically and genetically heterogeneous condition. Complex I is a giant multiheteromeric enzyme composed of seven ND subunits encoded by mitochondrial DNA (mtDNA) genes, and at least 38 subunits encoded by nuclear genes. To establish the contribution to human mitochondrial encephalopathy of ND versus nuc...

Altered metabolism is an important feature of many epileptic syndromes but has not been reported in Dravet syndrome (DS), a catastrophic childhood epilepsy associated with mutations in a voltage-activated sodium channel, Nav1.1 (SCN1A). To address this, we developed novel methodology to assess real-time changes in bioenergetics in zebrafish larvae between 4 and 6 d postfertilization (dpf). Base...

It has been confirmed that mitochondrial impairment may underlie both sporadic and familial Parkinson's disease (PD). Mitochondrial fission/fusion and biogenesis are key processes in regulating mitochondrial homeostasis. Therefore, we explored whether the protective effect of resveratrol in rotenone-induced neurotoxicity was associated with mitochondrial fission/fusion and biogenesis. The resul...

Pioglitazone (PG) is one of thiazolidinediones used for the treatment of type II diabetes mellitus. Some reports of its hepatotoxicity exist, but the mechanism of its hepatotoxicity is not well known. In the present study, the protective effect of some ATP suppliers are investigated against mitochondrial toxicity of PG in isolated rat mitochondria. Mitochondrial viability was investigated by MT...

In the chestnut blight fungus Cryphonectria parasitica, cytoplasmically transmissible hypovirulence phenotypes are elicited by debilitating mitochondrial DNA (mtDNA) mutations. In virus-free hypovirulent strains of C. parasitica from nature, the presence of a mitochondrial DNA element, named InC9, has been reported to cause similar disease syndromes. We have detected an additional mitochondrial...