RESEARCH INTERESTS
The Houser laboratory was established in 1979. The initial focus was on those processes that determine the electrical and contractile properties of the normal ventricular cardiac myocyte and the defects in those processes that lead to electrical instability (arrhythmias and sudden death) and poor cardiac pump performance (congestive heart failure (HF)). The Houser laboratory is arguably one of the first translational cardiac disease labs in the world.
Early cardiac cell physiology studies documented that Ca2+ regulation in hypertrophic heart disease is abnormal. The lab was one of the first to show that Ca2+ uptake and release from the sarcoplasmic reticulum (SR) is abnormal in failing cardiac myocytes and this abnormality remains a major therapeutic HF target. Early studies also showed that the development of HF involves a lengthening of the cardiac action potential duration (QT interval) to explain the link between pathological cardiac hypertrophy and arrhythmogenic sudden death.
The early basic studies in the lab were the first to document Ca2+-induced SR Ca2+ release as the sole mechanism underlying excitation-contraction coupling in adult mammalian heart cells.
The science in the lab evolved to studies that explored the idea that activation of Ca2+ dependent signaling pathways (mainly through CAMKII) regulate Ca2+ handling proteins in diseased myocytes. We developed techniques in live cells to track Ca2+ dependent activation of NFAT and we characterized the associated alterations in cell function. These studies were performed in collaboration with Dr. Jeffrey Molkentin at the University of Cincinnati.
The field began to realize that ischemic heart disease was a disease of cardiac myocyte death and the reason for progressive declines in cardiac function was primarily the result of the loss of cardiac myocytes coupled with the inability of surviving myocytes to proliferate. Therefore, we studied the mechanisms of myocyte death and explored the idea that new myocytes could be generated by activation of a “cardiac stem cell”. We identified a novel cortical bone stem cell that could reduce damage of the heart after myocardial infarction. These cells appeared to have some ability to generate new myocytes, but their primary mechanism of cardiac repair was via regulation of the post MI immune response.
We have worked with Dr. Walter Koch to developing therapies to prevent and reverse heart damage and we have been on a quest to prevent and repair damage to the heart cells. The goals were to improve the lives of patients with heart disease. Research breakthroughs like these could mean that we are just steps away from dramatically changing the way that heart disease is treated. Watch this video to understand what we are trying to accomplish.
The next decades of studies by multiple students and fellows explored many novel aspects of cardiac adaptation to disease stress. One area of research involved defining mechanisms of cardiac myocyte dysfunction using explanted human hearts. These studies were done with Ken Margulies, now at Penn. Many important studies were published but the one I will mention showed that when heart failure patients are supported with a ventricular assist devise their cardiac myocytes, with very poor structure and function, recover. These studies documented the incredible plasticity of the human heart cells. These studies also showed that the primary reason for HF was the death of myocytes and the subsequent adverse remodeling of surviving cells that were overworked.
Dr. Houser is now an Emeritus Professor. His commitment to science and discovery has not changed. He continues to help guide some research projects. A recent example is a study with a former fellow, Dr. Wei Wang, that uses a novel approach to induce damaged myocytes to complete the cell cycle to form new myocytes.
Dr. Houser has been a volunteer for the American Heart Association since 1979. He has served on numerous committees, the Board, and as the volunteer President in 2016-2017. He continues to serve as an AHA volunteer Award Recipient - 62nd Annual AHA Philadelphia Heart Ball
Dr. Houser was given the Edward S. Cooper M.D. Award at the American Heart Association (AHA) Philadelphia Heart Ball on February 9, 2019. The award honors "a physician, researcher or medical professional whose many outstanding contributions to the Philadelphia community exemplify the best of humankind." Dr. Houser has a long association with the AHA. This video may help explain much of his career at Temple and the reasons for his passion for scientific discovery and the translation of new knowledge into therapies that improve lives.
EDUCATION, TRAINING & CREDENTIALS
- Postdoctoral Fellowship, Cardiology, Lewis Katz School of Medicine at Temple University
- PhD, Physiology, Lewis Katz School of Medicine at Temple University
- BA, Biology and Chemistry, Eastern College
PUBLICATIONS