Poster, Podium & Video Sessions
Presentation Authors: M. Raj Rajasekaran*, Johnny Fu, My-Uyen (Lilly) Nguyen, Valmik Bhargava, San Diego, CA
Introduction: Previous studies show an age-related increase in the prevalence of urinary incontinence (UI) (10-15% in adults and ~30% % in older population >70 years). Age-related degenerative changes to urethral sphincter muscles are recognized as the most common cause for UI in the geriatric population. Recently, Wntβ catenin signaling pathway is recognized as the major molecular pathway involved in age-related skeletal muscle fibrosis. We tested the hypothesis that increased urethral sphincter fibrosis during advanced aging is mediated by a novel Wnt-β catenin signaling pathways.
Methods: We used a rabbit model to establish time course of age-related urethral sphincter muscle complex dysfunction and for further evaluation of molecular mechanisms of muscle dysfunction /fibrosis in rabbits. We employed (n=3) young (6-9 months), middle age (>12 months) and old rabbits (>30 months) and harvested mid-urethra (for rhabdosphincter) samples to evaluate protein and mRNA levels of markers of fibrosis using Western blot (protein) /qPCR (mRNA) studies respectively.
Results: Our rabbit studies confirmed age-related changes in alterations in closure pressure as well as in protein/mRNA levels of markers of fibrosis (β-catenin, collagen-I, and TGF-β etc; Fig A-C). These observations confirm our hypothesis that age-related increase in fibrogenic proteins mediated via Wntβ catenin signaling pathways may contribute to sphincter muscle dysfunction.
Conclusions: Our physiological and molecular studies are consistent with our hypothesis that age-related increase in fibrogenic proteins contribute to sphincter muscle function. Targeting Wnt signaling pathway may be beneficial in preventing sphincter muscle fibrosis.
Source Of Funding: VA Rehabilitation Research Merit Award
Dr. Rajasekaran, PhD, is a Research Pharmacologist at San Diego Veterans Hospital and an Associate Professor of Surgery at the University of California San Diego Medical Center, San Diego, California, USA.
Dr. Rajasekaran received his PhD from the University of Madras, Department of Pharmacology, India. He has focused his research on stem cell biology, tissue regeneration, incontinence and reproductive toxicology. His current areas of research include development of animal models for urinary and fecal incontinence, stem therapy for urological disorders, mechanism of age-related male sexual dysfunction.
As an accomplished Pharmacology Scientist for over 25 years, Dr. Rajasekaran has received national and international recognition for research. This includes prestigious awards, such as, the Uvnas prize for best publication in Immunopharmacology, and a national scholar award from the American Urological Association. During this time, he has made numerous contributions to Pharmacological research, beginning with establishment of the first in-vitro cell culture model in the year 2000, followed by stem cell research in this area. These models have brought in substantial funding from the drug industry. As an academic researcher, he has also served as principal/co-investigator of US- federal and industry funded contract projects working with Medicinova Inc, Myogen Inc, Acetlion Pharmaceuticals, Vivus Inc, cook Urological and Pharmacia & Upjohn. This has led to IND submissions with the FDA and clinical trials.
Dr. Rajasekaran. has authored over 60 articles in these areas, which have been published in journals including American Journal of Physiology, The Journal of Urology, Urology, the Journal of Andrology, and the International Journal of Andrology. His abstracts have been presented at meetings of the American Urological Association (AUA) and the International Society of Andrology on many topics, including stem cell applications for genito-urinary disorders.
Saturday, May 13
3:30 PM – 5:30 PM
Saturday, May 13
3:30 PM – 5:30 PM
Monday, May 15
1:00 PM – 3:00 PM