title: The role of autophagy and lipolysis in survival of astrocytes under nutrient deprivation.
abstract: Astrocytes can survive nutrient deprivation (ND) for days. However, the pro-survival strategy of astrocytes under such a metabolic challenge is still not clear. In the present study, we examined the effects of inhibition of two potential steps in energy acquisition during ND: autophagy (using chloroquine) and lipolysis (using orlistat). The inhibition of autophagy did not show significant effects on cell viability until 8-9h of ND. From that point onwards, the number of dead cells gradually increased, reaching ∼60% between 10 and 12h of ND. In addition, early inhibition of autophagy made astrocytes more vulnerable to the latter ND. The inhibition of lipolysis decreased the viability of cells exposed to ND, but this appeared much later compared to the inhibition of autophagy. The application of orlistat prevented ND-related hyperpolarization of the mitochondrial membrane, and mitochondria became swollen. This study clearly shows that autophagy and lipolysis are essential for the survival of astrocytes under ND conditions, which might be related to their role as neuron-supporting cells.
authors.affiliation: Center for Laser Microscopy, Department of Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Studentski trg 3, P.O. Box 52, 11001 Belgrade, Serbia.
authors.forename: Andrej
authors.initials: A
authors.lastname: Korenić
authors.affiliation: Center for Laser Microscopy, Department of Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Studentski trg 3, P.O. Box 52, 11001 Belgrade, Serbia.
authors.forename: Pavle
authors.initials: P
authors.lastname: Andjus
authors.affiliation: Center for Laser Microscopy, Department of Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Studentski trg 3, P.O. Box 52, 11001 Belgrade, Serbia.
authors.forename: Lidija
authors.initials: L
authors.lastname: Radenović
authors.affiliation: Department of Life Sciences, Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11030 Belgrade, Serbia. Electronic address: redoxsci@gmail.com.
authors.forename: Ivan
authors.initials: I
authors.lastname: Spasojević
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D001343:Autophagy; D002470:Cell Survival; D002738:Chloroquine / Q000494:pharmacology; D003470:Culture Media; D004734:Energy Metabolism; D007783:Lactones / Q000494:pharmacology; D008049:Lipase / Q000037:antagonists & inhibitors; D008066:Lipolysis; D000077403:Orlistat; D061251:Primary Cell Culture; D016548:Prosencephalon / Q000166:cytology; D051381:Rats
chemical_list: D003470:Culture Media; D007783:Lactones; D002738:Chloroquine; D000077403:Orlistat; D008049:Lipase
keywords: Astrocytes; Autophagy; Lipolysis; Mitochondrial membrane potential; Nutrient deprivation