title: Dual effects of carnosine on energy metabolism of cultured cortical astrocytes under normal and ischemic conditions.
abstract: OBJECTIVE
  The aim of this study was to investigate the effects of carnosine on the bioenergetic profile of cultured cortical astrocytes under normal and ischemic conditions.
  
  
  METHODS
  The Seahorse Bioscience XF96 Extracellular Flux Analyzer was used to measure the oxygen consumption rates (OCRs) and extracellular acidification rates (ECARs) of cultured cortical astrocytes treated with and without carnosine under normal and ischemic conditions.
  
  
  RESULTS
  Under the normal growth condition, the basal OCRs and ECARs of astrocytes were 21.72±1.59 pmol/min/μg protein and 3.95±0.28 mpH/min/μg protein respectively. Mitochondrial respiration accounted for ~80% of the total cellular respiration and 85% of this coupled to ATP synthesis. Carnosine significantly reduced basal OCRs and ECARs and ATP-linked respiration, but it strikingly increased the spare respiratory capacity of astrocytes. The cellular ATP level in carnosine-treated astrocytes was reduced to ~42% of the control. However, under the ischemic condition, carnosine upregulated the mitochondrial respiratory and cellular ATP content of astrocytes exposed to 8h of oxygen-glucose deprivation (OGD) followed by 24 h of recovery under the normal growth condition.
  
  
  CONCLUSIONS
  Carnosine may be an endogenous regulator of astrocyte energy metabolism and a clinically safe therapeutic agent for promoting brain energy metabolism recovery after ischemia/reperfusion injury.
authors.affiliation: Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou 325035, China. Electronic address: yueshen-2002@163.com.
authors.forename: Yao
authors.initials: Y
authors.lastname: Shen
authors.affiliation: Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou 325035, China.
authors.forename: Yueyang
authors.initials: Y
authors.lastname: Tian
authors.affiliation: Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou 325035, China.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Yang
authors.affiliation: Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou 325035, China.
authors.forename: Xiaojie
authors.initials: X
authors.lastname: Shi
authors.affiliation: Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou 325035, China.
authors.forename: Li
authors.initials: L
authors.lastname: Ouyang
authors.affiliation: Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou 325035, China.
authors.forename: Jieqiong
authors.initials: J
authors.lastname: Gao
authors.affiliation: Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, College of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou 325035, China. Electronic address: jxlu313@163.com.
authors.forename: Jianxin
authors.initials: J
authors.lastname: Lu
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000166:cytology* / Q000378:metabolism*; D002545:Brain Ischemia / Q000378:metabolism*; D002336:Carnosine / Q000378:metabolism*; D002478:Cells, Cultured; D004734:Energy Metabolism; D010101:Oxygen Consumption; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D002336:Carnosine
keywords: Glycolysis; Mitochondrial respiration; Oxidative phosphorylation (OXPHOS); Oxygen–glucose deprivation (OGD)/recovery