Aquaporin 4 and its Relationship with Brain Astrocytomas – Literature Review

Abstract Background Aquaporins (AQPs) are a family of membrane proteins that regulate the osmotic permeability plasma membrane. There described in literature total 13 types mammals, each with different places expression. In addition to water, some AQPs allow passage glycerol and ammonia, being called Aquaglyceroproteins. central nervous system, 1 4 expressed, responsible for water regulation blood-brain barrier. These two believed participate pathophysiological process governs behavior various CNS diseases, such as trauma primary tumors. More particularly, there quite controversial data on expression AQP4 tumors its relationship disease progression treatment possibility. Objective This paper aims perform review function this compile what is subject raise new possible research hypotheses. Methods The PUBMED platform was used bibliographic survey using “Aquaporin 4,” “expression” “astrocytomas” keywords. Articles older than 2008 articles did not address astrocytomas were excluded. selected articles, following topics investigated: structure, brain tumor localization, peritumoral edema. Results Regarding structure location AQP4, presents isoforms AQP4: M1 M23. Both form clusters “orthogonal arrays - OAPs.” tissue, shows decrease formation OAPs an increase both isoforms, besides losing their polarity, diffusing through cytoplasmic As tumors, assists cell migration invasion, participating proliferation apoptosis. cerebral edema, knowledge. Studies have shown increased aggravates cytotoxic edema cells and, by assisting angiogenesis, indirectly assist vasogenic breaking Other studies, however, point protective mechanism combat occurs formation. Furthermore, therapeutic proposal which, inhibiting expression, rats glioblastoma. Discussion literature, difference histopathological between high low grade gliomas. However, common changes them. could then be factor severity or evolution low-grade high-grade Moreover, it yet perceive true VEGF Finally, can hypothesized since ratio normal tissue greater due either decreased M23 isoform M1. Conclusion Further studies needed understand physiology pathophysiology involving create effective proposals disease.