title: High dietary taurine inhibits myocardial apoptosis during an atherogenic diet: association with increased myocardial HSP70 and HSF-1 but not caspase 3.
abstract: OBJECTIVE
  Apoptosis is a major cause of myocyte death, and taurine is anti-apoptotic. Heat shock protein 70 (HSP70) (which is regulated by heat shock factor-HSF-1) is also anti-apoptotic, and caspase 3 stimulates the apoptotic pathway. This study investigated whether taurine affects atherogenic diet-induced myocardial apoptosis, and whether HSP70, HSF-1 and caspase 3 are involved.
  
  
  METHODS
  New Zealand white rabbits were divided into 3 groups for 4 weeks according to their diet. Group 1 (control) was fed a normal rabbit diet; Group 2 (MC) received a normal rabbit diet with 1% methionine plus 0.5% cholesterol. Group 3 received MC diet + 2.5% taurine (MCT).
  
  
  RESULTS
  The atherogenic diet did not affect myocardial HSP70 or HSF-1 protein, but increased myocardial apoptotic nuclei to 40% (p < 0.01) versus 7% in con and 12% in MCT (p < 0.01). However, in MCT, myocardial HSP70 expression increased by 42.7% versus con and MC (p = 0.016), HSF-1 by 12% versus con and MC (p < 0.05), and total nuclei count increased by 37% versus MC (p < 0.05). Caspase 3 subunits remained unchanged in all groups, and HSP70 was increased approximately twofold in endothelial layer of arterioles (p = 0.01).
  
  
  CONCLUSIONS
  This study shows that taurine could reduce myocardial apoptotic nuclei and thus confer myocardial cytoprotection via stimulating myocardial HSP70 via HSF-1 and caspase 3-independent mechanisms.
authors.affiliation: Department of Medicine, Austin Health, University of Melbourne, Melbourne, VIC, Australia.
authors.forename: M
authors.initials: M
authors.lastname: Setyarani
authors.forename: A
authors.initials: A
authors.lastname: Zinellu
authors.forename: C
authors.initials: C
authors.lastname: Carru
authors.forename: A
authors.initials: A
authors.lastname: Zulli
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000627:therapeutic use; D017209:Apoptosis; D001160:Arterioles / Q000201:enzymology / Q000378:metabolism / Q000473:pathology; D050197:Atherosclerosis / Q000209:etiology / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D002316:Cardiotonic Agents / Q000627:therapeutic use; D053148:Caspase 3 / Q000378:metabolism; D003331:Coronary Vessels / Q000201:enzymology / Q000378:metabolism / Q000473:pathology; D004268:DNA-Binding Proteins / Q000819:agonists* / Q000378:metabolism; D004036:Diet, Atherogenic / Q000009:adverse effects; D019587:Dietary Supplements; D004730:Endothelium, Vascular / Q000201:enzymology / Q000378:metabolism / Q000473:pathology; D018840:HSP70 Heat-Shock Proteins / Q000819:agonists* / Q000378:metabolism; D000076249:Heat Shock Transcription Factors; D007150:Immunohistochemistry; D008297:Male; D009206:Myocardium / Q000201:enzymology / Q000378:metabolism* / Q000473:pathology; D018384:Oxidative Stress; D011817:Rabbits; D011897:Random Allocation; D013654:Taurine / Q000627:therapeutic use*; D014157:Transcription Factors / Q000819:agonists* / Q000378:metabolism
chemical_list: D000975:Antioxidants; D002316:Cardiotonic Agents; D004268:DNA-Binding Proteins; D018840:HSP70 Heat-Shock Proteins; D000076249:Heat Shock Transcription Factors; D014157:Transcription Factors; D013654:Taurine; D053148:Caspase 3