Cardiovascular disease affects an estimated 86.3 million Americans according to the American Heart Association with heart failure (HF) as the most prevalent form. Nicholas T. Lam and associates of Melbourne, Australia recently highlighted nerve growth factor (NGF) as a means to attenuate heart failure’s lethal nature.
Heart failure is a condition in which the heart either cannot pump enough blood to the body with sufficient force or the heart cannot take in enough blood at one time. The cause of such happenings is a weakened heart due to loss of cardiomyocytes, heart muscle cells, in many cases. The heart has a weak regenerative response compared to most organs such as the skin or liver. It was hypothesized that NGF may promote cardiac regeneration by either stopping cardiomyocyte death or promoting proliferation, therefore, a zebrafish model was used to test.
Cardiac injury resulting in HF in zebrafish was induced using aristolochic acid (AA). AA treated zebrafish developed HF in 37.5% of cases resulting in death of 20.8% of the population compared to controls in which no HF or death was seen (P<0.001). Additionally, AA treated zebrafish showed a large drop in cardiomyocytes.
Following treatment with NGF, HF incidence was reduced by 50% and death by 65% (P<0.01). Further tests revealed NGF was decreasing heart failure by promoting cardiac regeneration via increased cardiomyocyte proliferation. Increased cardiomyocyte numbers may be the result of increased hormone secretion from the greater number of sustained nerves due to NGF. Further testing is necessary.
Because of the huge decrease in heart failure and subsequent death seen in zebrafish, NGF presents as a potential drug target to combat heart disease. If parallel mammalian pathways are found, these results may prove extremely useful as a means to decrease human heart failure.
Nicholas T. Lam, Peter D. Currie, Graham J. Lieschke, Nadia A. Rosenthal, David M. Kaye. 2012. Nerve Growth Factor Stimulates Cardiac Regeneration via Cardiomyocyte Proliferation in Experimental Heart Failure. PLoS ONE.