Mitochondrial membrane permeability transition pore (mPTP)

The mitochondrial membrane permeability transition pore (mPTP) is a high-conductance, non-selective channel that forms in the inner mitochondrial membrane under conditions of cellular stress, such as calcium overload or oxidative damage. Its opening leads to the dissipation of the mitochondrial membrane potential, swelling of the mitochondrial matrix, and the release of pro-apoptotic factors like cytochrome c, ultimately triggering cell death via apoptosis or necrosis. While its exact molecular composition remains a subject of debate, Cyclophilin D is widely recognized as a key regulatory protein that facilitates pore opening. The mPTP is a critical therapeutic target in conditions characterized by excessive cell death, particularly ischemia-reperfusion injury in the heart and brain, as well as various neurodegenerative disorders. Pharmacological inhibition of the mPTP, primarily through the targeting of Cyclophilin D with drugs like Cyclosporine A or its non-immunosuppressive derivatives, aims to preserve mitochondrial integrity and improve cell survival during pathological insults.

Other names

Mitochondrial permeability transition poreMPTPPTPMitochondrial megachannelPermeability transition pore complex

Inhibition of pore opening by binding to regulatory components like Cyclophilin D, or stabilization of the closed state to prevent mitochondrial swelling and cytochrome c release.