Pro-inflammatory role of cell-free mitochondrial DNA in cardiovascular diseases.

Cardiovascular disease (CVD) is a major cause of morbidity and mortality. Inflammation contributes to the pathogenesis and progression of CVD. Circulating cell-free mitochondrial DNA (ccf-mtDNA) is that mtDNA fragments are released outside the cell and into the circulation by cell necrosis and secretion. The levels of ccf-mtDNA are increased in CVD and associated risk conditions, including hypercholesterolemia, diabetes mellitus, and arterial hypertension. MtDNA containing unmethylated CpG dinucleotides and can trigger inflammation that aggravates tissue injury by activating toll-like receptor 9, inflammasomes, and the stimulator of interferon genes pathway. Here, we review the expanding field of ccf-mtDNA-mediated inflammation and its role in the progression of CVD.