Bromodomains in Human-Immunodeficiency Virus-Associated Neurocognitive Disorders: A Model of Ferroptosis-Induced Neurodegeneration

Abstract

Graphical AbstractBoth HIV-1 and cART alter the lysosomes, increasing intracellular iron and the risk of ferroptosis. Dysfunctional lysosomes release the ferroptosis drivers iron, Ca2+ and cathepsin B (catB), promoting neuronal and oligodendrocyte loss, reflected in the white and gray matter pathology. The host responds to lysosomal damage by activating an epigenetic axis comprised of bromodomain 4 (BRD4) and microRNA-29 family (miR-29) that promptly suppresses lysosomal function, lowering ferritinophagy. As there is an inverse relationship between miR-29 and BRD4, HIV-1 inhibition of miR-29, upregulates BRD4, blocking ferritinophagy. The BRD4/miR-29 system also inhibits iron regulatory protein-2 (IRP-2) and augments cystine/glutamate antiporter xCT (SLC7A11), lowering the odds of ferroptosis.