Mitochondrial abnormalities are well-known to cause cognitive decline. However, the underlying molecular basis of mitochondria-associated neuronal and synaptic dysfunction in the diabetic brain remains unclear. Here, using a mitochondrial single channel patch clamp and cyclophilin D (CypD)-deficient mice (Ppif -/-) with streptozotocin (STZ)-induced diabetes, we observed an increase in the probability of Ca2+-induced mitochondrial permeability transition pore (mPTP) opening in brain mitochondria of diabetic mice, which was further confirmed by mitochondrial swelling and cytochrome c release induced by Ca2+ overload. Diabetes-induced elevation of CypD triggers enhancement of F1F0 ATP synthase-CypD interaction, which in turn leads to mPTP opening. Indeed, in patients with diabetes, cognitive function was negatively correlated with brain CypD protein levels. Notably, blockade of the F1F0 ATP synthase–CypD interaction by CypD ablation protected against diabetes -induced mPTP opening, ATP synthesis deficits, oxidative stress and mitochondria dysfunction. Furthermore, the absence of CypD alleviated deficits in synaptic plasticity, and learning and memory in diabetic mice. Thus, blockade of ATP synthase interaction with CypD provides a promising new target for therapeutic intervention in diabetic encephalopathy.
- Received May 4, 2016.
- Accepted August 4, 2016.
- © 2016 by the American Diabetes Association.