Briefly, mutations in the mitochondria-coded MT-ND1 gene, an important composition of respiratory complex I, is closely associated with energy metabolic impairment to influence balance of succinate and alpha-ketoglutarate, which leads to the abnormal citric acid cycle metabolites (succinate and alpha-ketoglutarate) to be responsible for HIF1alpha stabilization in pituitary adenomas (44). Here, HIF1A is linked to pituitary gland adenoma.