title: Exercises in hot and humid environment caused liver injury in a rat model.
abstract: OBJECTIVE
  To investigate injury pattern during intense exercises in hot and humid environment particularly on liver in a rat exertional heat stroke model.
  
  
  METHODS
  We randomly divided 30 rats into a control group (CG), a normal temperature (25±2°C, 60%±5% humidity) exercise group (NTEG) and a high temperature and high humidity (35±2°C, 80%±10% humidity) exercising group (HTEG), each comprising 10 animals. The NTEG and HTEG rats were forced to run in a treadmill for 1 hour maximum at 20 rpm. We analyzed liver cells of all three groups with JC-1 dye and flow cytometry for apoptosis rates in addition to liver tissue 8 - hydroxy deoxyguanosine (8 - OhdG) and blood serum IL-6, tumor necrosis factor alpha (TNF-α), alanine aminotransferase ALT, aspartate amino transferase (AST), serum creatinine (CREA), blood urea nitrogen (BUN), lactate dehydrogenase (LDH), creatine phosphate kinase (CK) concentrations.
  
  
  RESULTS
  Compared with NTEG rats, beside reduced exercise tolerance (60±5 vs. 15±3 minutes) (p = 0.002) the 8-OhdG liver tissue concentrations were significantly higher (p = 0.040) in the HTEG rats. The HTEG developed more organ tissue damage and cellular fragmentations of liver cells. In both exercise groups TNF-α and IL-6 serum concentrations were enhanced significantly (p<0.001) being highest in the HTEG animals. Serum ALT, AST, LDH, CREA, BUN and CK concentrations were significantly enhance in both exercise groups.
  
  
  CONCLUSIONS
  In our exertional heat stroke rat model, we found tissue damage particularly in livers during exercises in hot and humid environment that was related to inflammation, oxidative stress and apoptosis.
authors.affiliation: Department of Hepatobiliary Medicine, Fuzhou PLA General Hospital, Fuzhou Fujian, China.
authors.forename: DongLiang
authors.initials: D
authors.lastname: Li
authors.affiliation: Department of Hepatobiliary Medicine, Fuzhou PLA General Hospital, Fuzhou Fujian, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Hepatobiliary Medicine, Fuzhou PLA General Hospital, Fuzhou Fujian, China.
authors.forename: Bang
authors.initials: B
authors.lastname: Liu
authors.affiliation: Department of Hepatobiliary Medicine, Fuzhou PLA General Hospital, Fuzhou Fujian, China.
authors.forename: YuZheng
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Hepatobiliary Medicine, Fuzhou PLA General Hospital, Fuzhou Fujian, China.
authors.forename: ZhiYu
authors.initials: Z
authors.lastname: Zeng
authors.affiliation: Department of Hepatobiliary Medicine, Fuzhou PLA General Hospital, Fuzhou Fujian, China.
authors.forename: LingLing
authors.initials: L
authors.lastname: Lu
authors.affiliation: Department of Pathology, Fuzhou PLA General Hospital, Fuzhou, Fujian, China.
authors.forename: ZhiYong
authors.initials: Z
authors.lastname: Zheng
authors.affiliation: Department of Hepatobiliary Medicine, Fuzhou PLA General Hospital, Fuzhou Fujian, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Li
authors.affiliation: Clinical laboratory, No.476 hospital of PLA Fujian, Fuzhou, Fujian, China.
authors.forename: ZongFu
authors.initials: Z
authors.lastname: Zheng
mesh_terms: D000818:Animals; D017209:Apoptosis; D004195:Disease Models, Animal; D018882:Heat Stress Disorders / Q000097:blood / Q000473:pathology; D006358:Hot Temperature / Q000009:adverse effects*; D006813:Humidity / Q000009:adverse effects*; D007249:Inflammation / Q000097:blood / Q000473:pathology; D008099:Liver / Q000293:injuries / Q000378:metabolism / Q000473:pathology; D008297:Male; D018384:Oxidative Stress; D010805:Physical Conditioning, Animal / Q000009:adverse effects*; D051381:Rats; D017207:Rats, Sprague-Dawley