Examining Various Aspects of Age-related Changes in Physiology in the Naked Mole-Rat
Dr. Rochelle Buffenstein of the Aging Animal Models and Longevity Assessment Core and her team have continued to examine various aspects of age-related changes in physiology in the naked mole-rat and within the past 5 years have discovered some significant breakthroughs.
- Bone quality
In this regard we have examined age-related changes in bone quality (Pinto et al., 2010) in a collaborative study undertaken with Karl Jepsen at the University of Michigan and Carl Terranova at CCNY. These bone data reveal that unlike mice naked mole-rats show extensive bone remodeling and are well able to maintain bone quality. We are currently discussing a new collaboration with Dr Kay Oyajobi (CSB, UTHSCSA) to examine the molecular mechanisms facilitating bone maintenance despite low sex steroid hormone levels.
- Cardiac Function
Using dobutamine echocardiography and pulsed wave Doppler, we have found that naked mole-rats, unlike all other mammals studied to date, well maintain cardiac function and cardiac reserve during aging (Grimes et al., 2012; Grimes et al., 2014). These studies were initiated as part of a collaboration with Dr. Merry Lindsey, Dr. Anil Reddy (Baylor), Dr Rick Lange (UTHSCSA)and H. Han (UTSA). To better delve into the mechanisms involved in sustained cardiac function we have recently forged collaborations with Dr Jean BoPassa (Physiology, UTHSCSA) to examine isolated cardiomyocyte responses and with Dr. Pieter de Tombe and Dr. Sakhtivel Saddayappan at Loyolla to examine the contractile machinery and single cell force transduction.
- Brain Aging
Astonishingly, despite high levels of oxidative damage in the various brain regions, naked mole-rats show no neuron loss or signs of plaques and tangles. Intriguingly, they also exhibit high levels of both beta amyloid and tau protein in the various brain regions (Edrey et al., 2013; Edrey et al., 2014), leading us to propose that these proteins may not be causally linked to neurodegenerative diseases but rather neuroprotective mechanisms employed to combat the various factors that lead to neurodegeneration. Components of these studies were done in collaboration with Dr Salvatore Oddo. If this were confirmed experimentally this too would be a significant paradigm shift for the field.