To elucidate the mechanisms for reverse LV remodeling, we generated a conditional (doxycycline [dox] off) transgenic mouse tetracycline transactivating factor–TRAF2 (tTA-TRAF2) that develops a dilated heart failure (HF) phenotype upon expression of a proinflammatory transgene, TNF receptor–associated factor 2 (TRAF2), and complete normalization of LV structure and function when the transgene is suppressed. tTA-TRAF2 mice developed a significant increase in LV dimension with decreased contractile function, which was completely normalized in the tTA-TRAF2 mice fed dox for 4 weeks (tTA-TRAF2dox4W). Normalization of LV structure and function was accompanied by partial normalization (~60%) of gene expression associated with incident HF. Similar findings were observed in patients with dilated cardiomyopathy who underwent reverse LV remodeling following mechanical circulatory support. Persistence of the HF gene program was associated with an exaggerated hypertrophic response and increased mortality in tTA-TRAF2dox4W mice following transaortic constriction (TAC). These effects were no longer observed following TAC in tTA-TRAF2dox8W, wherein there was a more complete (88%) reversal of the incident HF genes. These results demonstrate that reverse LV remodeling is associated with improvements in cardiac myocyte biology; however, the persistence of the abnormal HF gene program may be maladaptive following perturbations in hemodynamic loading conditions.
Veli K. Topkara, Kari T. Chambers, Kai-Chien Yang, Huei-Ping Tzeng, Sarah Evans, Carla Weinheimer, Attila Kovacs, Jeffrey Robbins, Philip Barger, Douglas L. Mann
Usage data is cumulative from April 2023 through April 2024.
Usage | JCI | PMC |
---|---|---|
Text version | 353 | 61 |
60 | 43 | |
Figure | 126 | 16 |
Supplemental data | 10 | 2 |
Citation downloads | 15 | 0 |
Totals | 564 | 122 |
Total Views | 686 |
Usage information is collected from two different sources: this site (JCI) and Pubmed Central (PMC). JCI information (compiled daily) shows human readership based on methods we employ to screen out robotic usage. PMC information (aggregated monthly) is also similarly screened of robotic usage.
Various methods are used to distinguish robotic usage. For example, Google automatically scans articles to add to its search index and identifies itself as robotic; other services might not clearly identify themselves as robotic, or they are new or unknown as robotic. Because this activity can be misinterpreted as human readership, data may be re-processed periodically to reflect an improved understanding of robotic activity. Because of these factors, readers should consider usage information illustrative but subject to change.