title: Monocyte-specific Bcl-2 expression attenuates inflammation and heart failure in monocyte chemoattractant protein-1 (MCP-1)-induced cardiomyopathy.
abstract: OBJECTIVE
  Infiltrating inflammatory cells within the myocardium have been shown to be apoptotic, but the significance of apoptotic inflammatory cells to the development of cardiomyopathy remains undefined. Transgenic mice with cardiac-specific expression of MCP-1 exhibit extensive apoptosis of infiltrating mononuclear cells and develop heart failure. Here, we tested the hypothesis that in vivo selective inhibition of apoptosis of infiltrating mononuclear cells would preserve cardiac structure and function and improve survival in this murine model.
  
  
  METHODS
  Mice with cardiac-specific expression of MCP-1 and monocyte-specific expression of Bcl-2 were generated by cross-breeding MCP-1 transgenic mice with hMRP8-Bcl-2 mice that over-express Bcl-2 in the monocytes. Structural and functional parameters and the inflammatory response of the heart were evaluated and compared between the wild-type and transgenic mice.
  
  
  RESULTS
  Expression of Bcl-2 in monocytes results in superior preservation of myocardial structure, cardiac function and a significant prolongation of survival of MCP-1 transgenic mice. The beneficial effects of monocyte-specific Bcl-2 expression are associated with inhibition of apoptosis of infiltrating mononuclear cells, normalization of circulating C-reactive protein levels, attenuation of cellular infiltrates, macrophage activation and production of proinflammatory cytokines, tumor necrosis factor (TNF-alpha), interleukin (IL)-1 beta and IL-6 in the hearts.
  
  
  CONCLUSIONS
  These results demonstrate that apoptosis of infiltrating mononuclear cells plays a detrimental role in the development of heart failure in this murine model, suggesting that modulation of apoptosis of infiltrating mononuclear cells may be of clinical benefit in heart failure.
authors.affiliation: Biomolecular Science Center and Department of Molecular Biology and Microbiology, Burnett College of Biomedical Science, University of Central Florida, FL 32816, USA. jniu@mail.ucf.edu
authors.forename: Jianli
authors.initials: J
authors.lastname: Niu
authors.forename: Asim
authors.initials: A
authors.lastname: Azfer
authors.forename: Pappachan E
authors.initials: PE
authors.lastname: Kolattukudy
mesh_terms: D000818:Animals; D017209:Apoptosis; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis; D018932:Chemokine CCL2 / Q000235:genetics / Q000378:metabolism*; D002634:Chemotaxis, Leukocyte; D004452:Echocardiography; D015870:Gene Expression; D006333:Heart Failure / Q000276:immunology* / Q000378:metabolism; D007150:Immunohistochemistry / Q000379:methods; D020287:In Situ Nick-End Labeling; D053583:Interleukin-1beta / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D008214:Lymphocytes / Q000378:metabolism* / Q000473:pathology; D008262:Macrophage Activation; D051379:Mice; D008817:Mice, Mutant Strains; D008822:Mice, Transgenic; D009206:Myocardium / Q000378:metabolism* / Q000473:pathology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016019:Survival Analysis; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
chemical_list: D015415:Biomarkers; D018932:Chemokine CCL2; D053583:Interleukin-1beta; D015850:Interleukin-6; D019253:Proto-Oncogene Proteins c-bcl-2; D014409:Tumor Necrosis Factor-alpha; D002097:C-Reactive Protein