Mixed messages: transcription patterns in failing and recovering human myocardium

Circ Res. 2005 Mar 18;96(5):592-9. doi: 10.1161/01.RES.0000159390.03503.c3. Epub 2005 Feb 17.

Abstract

In previous studies, mechanical support of medically refractory hearts with a left ventricular assist device (LVAD) has induced regression of many morphological and functional abnormalities characteristic of failing human hearts. To identify transcriptional adaptations in failing and LVAD-supported hearts, we performed a comprehensive transcription analysis using the Affymetrix microarray platform and 199 human myocardial samples from nonfailing, failing, and LVAD-supported human hearts. We also used a novel analytical strategy that defines patterns of interest based on multiple intergroup comparisons. Although over 3088 transcripts exhibited significantly altered abundance in heart failure, most of these did not exhibit a consistent response to LVAD support based on our analysis. Of those 238 with a consistent response to LVAD support, more than 75% exhibited persistence or exacerbation of HF-associated transcriptional abnormalities whereas only 11%, 5%, and 2% exhibited partial recovery, normalization, and overcorrection responses, respectively. Even among genes implicated by previous reports of LVAD-associated myocardial improvements, partial or complete normalization of transcription did not predominate. The magnitude of differences in transcript abundance between nonfailing and failing hearts, and between failing an LVAD-supported hearts, tended to be low with changes greater than or equal to 2-fold infrequently observed. Our results indicate that morphological or functional myocardial improvements may occur without widespread normalization of pathological transcriptional patterns. These observations also suggest that many failure-associated transcriptional changes have only a limited role in regulating cardiac structure and function and may represent epiphenomena and/or nonspecific myocardial plasticity responses. Differences in mRNA localization, translation efficiency, and posttranslational protein modifications or interactions may be more pivotal in regulating myocardial structure and function.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3-Phosphoinositide-Dependent Protein Kinases
  • Convalescence
  • Female
  • Gene Expression Profiling
  • Gene Expression Regulation*
  • Heart Failure / etiology
  • Heart Failure / genetics*
  • Heart Failure / metabolism
  • Heart Failure / pathology
  • Heart Failure / surgery
  • Heart Failure / therapy
  • Heart Transplantation
  • Heart-Assist Devices*
  • Humans
  • Male
  • Middle Aged
  • Myocardium / metabolism*
  • Myocardium / pathology
  • Oligonucleotide Array Sequence Analysis
  • Protein Serine-Threonine Kinases / biosynthesis
  • Protein Serine-Threonine Kinases / genetics
  • RNA, Messenger / biosynthesis
  • RNA, Messenger / genetics
  • Repressor Proteins / biosynthesis
  • Repressor Proteins / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Suppressor of Cytokine Signaling 3 Protein
  • Suppressor of Cytokine Signaling Proteins
  • Transcription Factors / biosynthesis
  • Transcription Factors / genetics
  • Transcription, Genetic*
  • Ventricular Dysfunction, Left / complications
  • Ventricular Dysfunction, Left / therapy

Substances

  • RNA, Messenger
  • Repressor Proteins
  • SOCS3 protein, human
  • Suppressor of Cytokine Signaling 3 Protein
  • Suppressor of Cytokine Signaling Proteins
  • Transcription Factors
  • 3-Phosphoinositide-Dependent Protein Kinases
  • Protein Serine-Threonine Kinases