9 April 2007
School of Medicine, Keio University Tokyo, JAPAN
Prof. Keiichi Fukuda of the Department of Regenerative Medicine and Advanced Cardiac Therapeutics of Keio University School of Medicine has been researching cardiac and cardiomyocyte regeneration, which has been supported by the Program for Promotion of Fundamental Studies in Health Sciences of the National Institute of Biomedical Innovation. Controlling the sympathetic innervation is indispensable for cardiac regeneration, and research on development and regeneration of cardiac nerves are also being conducted. The studies by Fukuda and others show that Sema3a, a type of intravital protein, establishes cardiac sympathetic innervation patterning, and that Sema3a-deficient mice and transgenic mice with overexpression of Sema3a both demonstrated arrhythmia, such as venticular tachycardia, and sudden death. These findings lead to the conclusion that Sema3a controls arrhythmia through sympathetic innervation patterning, and that inappropriate cardiac Sema3a expression in human beings can cause developmental abnormality of sympathetic innervation and can lead to sudden death. These finding also show the importance of regenerating sympathetic innervation in regenerating the heart with regenerated cardiomyocyte.
Details of the new findings are described in the advance online publication of “Nature Medicine”. http://www.nature.com/nm/journal/vaop/ncurrent/full/nm1570.html
This research shows that Sema3a is the key in determining the density and patterning of cardiac sympathetic innervation, that the cause of unexplained sudden deaths may include cases of genetic defects of Sema3a, that abnormal development of cardiac sympathetic innervation patterning may cause arrhythmia, and that these unknown etiologic genes can be targets for future medical treatment.
Also when regenerating the heart with regenerated cardiomyocyte, which will be realized in the near future, it is necessary to consider tissue-engineering methods to regenerate sympathetic innervation as well.
Inquiries: Prof. Keiichi Fukuda, Department of Regenerative Medicine and Advanced Cardiac Therapeutics of Keio University School of Medicine
Tel: +81-3-5363-3874 Fax: +81-3-5363-3875
Email: [email protected]
