['Our aim is to explore the associations between mitochondrial DNA (mtDNA) content and basal plasma glucose, plasma glucose after oral glucose administration and oxidative stress in a Chinese population with different levels of glucose tolerance. We also aimed to investigate the effect of mtDNA content on basal and oral glucose-stimulated insulin secretion.', "Five hundred and fifty-six Chinese subjects underwent a 75-g, 2-h oral glucose tolerance test. Subjects with diabetes (n\u2009=\u2009159), pre-diabetes (n\u2009=\u2009197) and normal glucose tolerance (n\u2009=\u2009200) were screened. Blood lipid profile was assessed, and levels of the oxidative stress indicators superoxide dismutase, glutathione reductase (GR) and 8-oxo-2'-deoxyguanosine (8-oxo-dG) were measured. Levels of HbA", 'Peripheral blood mtDNA content was positively associated with DI'] Is reduced peripheral blood mtDNA content associated with impaired glucose-stimulated islet β cell function in a Chinese population with different degrees of glucose tolerance?