Brain and retinal microglia in health and disease: An unrecognized target of the renin-angiotensin system

Abstract

Microglia are the resident immune cells within the brain and retina, commonly known as the macrophages of the central nervous system (CNS). Microglia survey the surrounding milieu to eliminate invading microbes, clear cellular debris and enforce programmed cell death by removing apoptotic cells. Complementary to their 'house-keeping' role, microglia are capable of releasing brain-derived neurotrophic factor (BDNF), as well as various anti-inflammatory cytokines that sustain and support neuronal survival. Although microglia are essential for maintaining a healthy CNS, paradoxically they may undergo phenotypic changes to influence numerous neurodegenerative disorders, including Parkinson's dis..