Targeted drug delivery to mammalian mitochondria in living cells

Mitochondrial dysfunction causes or contributes to a large number of human disorders including neuromuscular and neurodegenerative diseases, diabetes, ischaemia-reperfusion injury and cancer. Increasing efforts are being made towards mitochondria-directed pharmacological intervention, leading to the emergence of 'mitochondrial medicine' as a new field of biomedical research. The identification of new molecular mitochondrial drug targets in combination with the development of methods for selectively delivering biologically active molecules to the site of mitochondria will eventually launch new therapies for the treatment of mitochondria-related diseases, based either on the selective protection, repair or eradication of cells. This review discusses the need for the development of mitochondria-specific drug and DNA delivery systems, and evaluates the currently employed strategies for mitochondrial drug targeting, including some of their potential therapeutic applications.