Glaucoma is a group of ocular diseases that cause irreversible blindness. It is characterized by multifactorial degeneration of the optic nerve axons and retinal ganglion cells (RGCs), resulting in the loss of vision. Major components of glaucoma pathogenesis include glia-driven neuroinflammation and impairment of mitochondrial dynamics and bioenergetics, leading to retinal neurodegeneration. In this review article, we summarize current evidence for the emerging role of apolipoprotein A-I binding protein (AIBP) as an important anti-inflammatory and neuroprotective factor in the retina. Due to its association with toll-like receptor 4 (TLR4), extracellular AIBP selectively removes excess cholesterol from the plasma membrane of inflammatory and activated cells. This results in the reduced expression of TLR4-associated, cholesterol-rich lipid rafts and the inhibition of downstream inflammatory signaling. Intracellular AIBP is localized to mitochondria and modulates mitophagy through the ubiquitination of mitofusins 1 and 2. Importantly, elevated intraocular pressure induces AIBP deficiency in mouse models and in human glaucomatous retina. AIBP deficiency leads to the activation of TLR4 in Müller glia, triggering mitochondrial dysfunction in both RGCs and Müller glia, and compromising visual function in a mouse model. Conversely, restoring AIBP expression in the retina reduces neuroinflammation, prevents RGCs death, and protects visual function. These results provide new insight into the mechanism of AIBP function in the retina and suggest a therapeutic potential for restoring retinal AIBP expression in the treatment of glaucoma.

A-Kinase anchoring protein 1 (AKAP1) is a multifunctional mitochondrial scaffold protein that regulates mitochondrial dynamics, bioenergetics, and calcium homeostasis by anchoring several proteins, including protein kinase A, to the outer mitochondrial membrane. Glaucoma is a complex, multifactorial disease characterized by a slow and progressive degeneration of the optic nerve and retinal ganglion cells (RGCs), ultimately resulting in vision loss. Impairment of the mitochondrial network and function is linked to glaucomatous neurodegeneration. Loss of AKAP1 induces dynamin-related protein 1 dephosphorylation-mediated mitochondrial fragmentation and loss of RGCs. Elevated intraocular pressure triggers a significant reduction in AKAP1 protein expression in the glaucomatous retina. Amplification of AKAP1 expression protects RGCs from oxidative stress. Hence, modulation of AKAP1 could be considered a potential therapeutic target for neuroprotective intervention in glaucoma and other mitochondria-associated optic neuropathies. This review covers the current research on the role of AKAP1 in the maintenance of mitochondrial dynamics, bioenergetics, and mitophagy in RGCs and provides a scientific basis to identify and develop new therapeutic strategies that could protect RGCs and their axons in glaucoma.

Glaucoma is a group of ocular diseases that causes irreversible blindness worldwide and is characterized by a multifactorial degeneration of optic nerve and retinal ganglion cells (RGCs), leading to vision loss. One of the significant risk factors in glaucoma pathogenesis is glia-driven neuroinflammation. Impairment of mitochondrial dynamics and bioenergetics is associated with glaucomatous neurodegeneration and is linked to neuroinflammation. Apolipoprotein A-I binding protein (AIBP) binds to toll-like receptor 4 (TLR4) and facilitates the removal of excess cholesterol from the plasma membrane in activated cells, suggesting the regulation of cholesterol-driven inflammation by inhibiting the TLR4-associated lipid rafts. AIBP is localized in mitochondria and regulates mitophagy by ubiquitination of mitofusin 1 and 2. We observed elevated intraocular pressure-induced AIBP deficiency in glaucomatous neurodegeneration. We also observed that AIBP deficiency activated TLR4 in Müller glia, triggered mitochondrial dysfunction in both RGCs and Müller glia and impaired visual function. In mouse models of glaucoma, AIBP treatment protects RGCs by reducing inflammatory responses. Here, our review focuses on investigating the role of AIBP in the retina and examining the underlying mechanism by which AIBP contributes to the pathogenesis of glaucoma, aiming to provide new insight into the therapeutic potential for the treatment of glaucoma.