Grantee Spotlight Interview

Hiroshi Kumagai, PhD

Assistant Professor, University of Sothern California
Glenn Foundation for Medical Research and AFAR Grants for Junior Faculty - 2023

Hiroshi Kumagai

What inspired you to pursue aging research?

The realization that skeletal muscle has a crucial role in both mobility and overall health, combined with its relative under-addressed in the aging research field, inspired me to focus on aging muscle research. Sarcopenia-related muscle loss significantly impacts morbidity and mortality, yet its mechanisms and interventions remain well understudied. I'm driven to uncover the molecular intricacies of skeletal muscle aging, not only to understand the aging process but also to devise strategies that enhance muscle health, thereby improving the quality of life and longevity for the aging population.

In your view, what does AFAR mean to the field, and what does it mean, for you, to receive an AFAR grant now?

AFAR, is a pioneering organization that plays a pivotal role in advancing research dedicated to addressing the challenges and opportunities brought about by the aging process. Notably, AFAR also extends its support to international researchers without permanent residency. This inclusive approach is particularly valuable as it opens up research grant opportunities for those who often face limitations in eligibility. Receiving an AFAR grant at this early career stage is an honor and a validation of my commitment to unraveling the intricate complexities of skeletal muscle aging. This recognition underscores the significance of this research area and provides essential resources to expedite investigations into interventions that hold the potential to enhance the health and vitality of aging individuals on a global scale. Empowered by this grant, I am inspired to delve even deeper into my scientific pursuits, driving forward the progress toward a comprehensive understanding of skeletal muscle aging and its profound implications for healthspan.

What is exciting about your research’s potential impact?

Our research holds the potential to discover a novel microprotein responsible for inducing mitochondrial dysfunction and skeletal muscle disorders. This microprotein appears to be upregulated by both the aging process and physical inactivity, providing a potential explanation for the link between these factors and the development of mitochondrial dysfunction and skeletal muscle atrophy. Our current investigations are centered around developing methods to effectively inhibit this microprotein. Such inhibition could offer a promising therapeutic strategy for addressing conditions like sarcopenia and frailty.

How would you describe your research to a non-scientist?

Even though sarcopenia, which is the loss of muscle mass and strength, can lead to health problems and even death, right now the main ways to prevent it are just exercising and eating well. There aren't any medicines that work well for it. However, in our research, we found a new small-sized protein that seems to be linked to muscle loss/weakness. This protein amount is increased when people get older and don't move around much. This discovery might help explain why getting older and not staying active can cause sarcopenia. And if we can figure out how to stop this protein from working, it could be a really good way to help treat sarcopenia and could contribute to healthy aging.

Explore Dr. Kumagai's AFAR-supported research here

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