Future possibilities in glaucoma therapy

Glaucoma is a group of eye diseases causing irreversible optic nerve damage. This review presents 4 elements of future glaucoma treatment strategies: baroprotection, vasoprotection, neuroprotection and gene therapy. New baroprotection includes compounds that alter the actin cytoskeleton (rho-kinase inhibitors, latrunculin, cytochalasin), new drugs that enhance aqueous outflow via the trabecular meshwork (statins, steroid antagonists) and via the uveoscleral route (EP2 agonists, 5-HT2 agonists), as well as new classes of components that suppress aqueous humor formation (cannabinoids). Vasoprotection includes blocking reperfusion injury (NOS-2 inhibitors, endothelin blockers, MMP-9 inhibitors). Concerning neuroprotection antiamyloids antibodies, erythropoietin and caspase inhibitors are discussed. Gene therapy may target various effectors: the trabecular meshwork (cytoskeleton regulatory proteins, miocyllin, MMPs), the ciliary body epithelium (genes modifying aqueous humor production, neuropeptides), the ciliary body cells (MMPs, genes of local PGs biosynthesis, ciliary muscle relaxants), the retinal ganglion cells (neurotrophin genes, anti-apoptotic genes), Müller cells (neurotrophins, GLAST) and conjunctiva (gene of chloramphenicol acetyltransferase, inhibitor p21). Experimental studies on the graft mesenchymal stem cells and mature retinal cells to replace the dead retinal ganglion cells are advanced. Immunotherapy, offering a vaccination, providing protection against loss of retinal ganglion cells, has been investigated.