Dr. Brynn H. Voy
Assistant Professor

Education

Professional Interest: Adipose Tissue, Obesity, Adipokine, Genomics and
Gene Networks

Adipose tissue is no longer considered as a mere warehouse for storage of excess energy as triglycerides due to the discovery of its role as an endocrine tissue.  Adipocytes synthesize and secrete a wide variety of functionally diverse molecules collectively referred to as adipokines.  Adipokines act as messengers to many other physiological systems, creating a means through which adipose tissue not only stores excess energy but contributes to the regulation of other physiological pathways, including the immune, cardiovascular and reproductive systems.  Further, a number of adipokines participate in maintenance of energy balance, enabling adipose tissue to contribute to its own regulation.  Control of adipose endocrine function is tightly intertwined with energy storage, to the extent that both excess gain and loss of adipose tissue mass disrupt normal adipokine profiles and in turn negatively impact reproduction, immune function and other systems regulated by adipokines.

The driving concept behind much of the research being conducted by Dr. Voy’s laboratory is that disorders that accompany shifts in adipose mass – either toward obesity or excessive leanness – are in part driven by disruptions in the endocrine function of adipose tissue.  This concept positions adipokines as potential targets for interventions – e.g., diet, pharmaceuticals, management practices, selective breeding – to improve production and efficiency (in food animals) and alleviate obesity-associated disorders (in both food animals and humans).  Dr. Voy’s research uses a combination of gene expression profiling, physiological measurements, metabolomics, and computational and statistical analyses to build a systems level view of how adipokines contribute to the consequences of disturbed energy balance. A number of projects in this area are ongoing or planned:

1. Determining how nutrient availability and insulin signaling alter adipokine profiles in domestic chickens (collaboration with Dr. Jean Simon, INRA).
2. Characterizing the adipokine profiles of dairy cows as they relate to energy balance and fertility.
3. Uncoupling the genetic control of fatness from heritable regulation of adipokine levels using panels of mouse recombinant inbred strains.
4. Defining the impact of organic pollutants such as bisphenol A on adipose tissue development and the endocrine function of adipose tissue.

In addition, Dr. Voy is also conducting research that addresses the impact of low dose ionizing radiation on immune function.  Low dose radiation is an environmental stressor – much like heat stress – that elevates levels of free radicals and challenges the organism to cope with oxidative stress.  Her lab has shown that exposure of mice to a single dose of low level (10cGy) ionizing radiation activates neutrophils, which could have important implications for subsequent ability to respond to an immune challenge.  Her laboratory is currently integrating transcriptomic data with immunological phenotypes and measures of neutrophil function to uncover pathways through which the organism adapts to radiation exposure. While more relevant to humans, these same pathways may also be important in adaptation to heat stress and other environmental challenges that alter immune function in production animals.

Select Publications:

• Chesler EJ, Miller DR, Branstetter LR, Galloway LD, Jackson BL, Philip VM, Voy BH, Culiat CT, Threadgill DW, Williams RW, Churchill GA, Johnson DK, Manly KF. The Collaborative Cross at Oak Ridge National Laboratory: developing a powerful resource for systems genetics. Mamm. Genome, 19(6): 382-9, 2008.
• Voy BH, Scharff JA, Perkins AD, Saxton AM, Borate B, Chesler EJ, Branstetter LK, Langston MA. Extracting gene networks for low dose radiation using graph theoretical algorithms. PLoS Comp Bio, 21:e89, 2006. 
• Kim S, Bejnood MS, Quignard-Boulange A, Massiera F, Teboul M, Ailhaud G, Naima Moustaid-Moussa N, Voy BH. The adipose renin-angiotensin system modulates systemic insulin sensitivity and activates the intrarenal renin-angiotensin system.  J. Biomed. Biotechnol, 5:27012, 2006.
• Jones BH, Standridge MK, Moustaid N.  Angiotensin II increases lipogenesis in 3T3-L1 and human adipose cells.  Endocrinology 138: 1512-1519, 1997.