Table 1.

The alterations of cell-free circulating and urinary mtDNA and their correlations with acute kidney injury and chronic kidney diseases.

Disease category	Biomarker	Alteration	Disease correlation	Refs
AKI	Circulating mtDNA	Not significantly changed	Not significantly correlated with inflammation and renal injury	[16, 75, 77]
	Urinary mtDNA	Increased	Correlated positively with renal injury, negatively with eGFR and intrarenal mtDNA level	[74–77]
Nondiabetic CKD	Urinary mtDNA	Increased	Correlated positively with renal injury and eGFR decline	[88–90]
DKD	Circulating mtDNA	Decreased	Correlated negatively with inflammation and renal injury	[111]
	Urinary mtDNA	Increased	Correlated positively with inflammation and interstitial fibrosis, negatively with renal function	[108, 111]

Note: AKI, acute kidney injury; CKD, chronic kidney disease; DKD, diabetic kidney disease; eGFR, estimated glomerular filtration rate.