Aging and a sedentary lifestyle lead to changes in skeletal muscle and the vasculature that result in insulin resistance and an increased risk for developing type 2 diabetes mellitus. This places older adults at substantially greater risk for diabetes-associated cardiovascular disease, microvascular complications, and impaired angiogenesis. My research examines the mechanisms by which exercise training improves the treatment and prevention of type 2 diabetes and the abnormalities in skeletal muscle and the vasculature that are associated with insulin resistance.
My current studies examine:
- Mechanisms underlying reduced skeletal muscle capillarization and endothelial dysfunction in obesity and insulin resistance;
- Age- and deconditioning-mediated changes in endothelial progenitor cells (EPC) in aging and insulin resistance; and
- The effects of aerobic exercise training on EPC number and function, as well as downstream effects on angiogenesis, vasoreactivity, and insulin sensitivity.
I am currently the recipient of a NIH Paul B. Beeson Patient-Oriented Career Development Award in Aging entitled "Effects of Aerobic Exercise on EPCs and Vascular Dysfunction in Aging and Type 2 Diabetes". I also direct a subcontract on a NIH R21 grant entitled "Potential Role of Endothelial Progenitors Cells in Cardiovascular Risk", and I am a recipient of the 2007 New Investigator Research Award from The Obesity Society.
Caldwell, K.J., Prior, S.J., M. Kampmann, L. Zhao, S. McEvoy, B.K. Lal. Upper body exercise increases lower extremity venous blood flow in deep vein thrombosis. Journal of Vascular Surgery. In press.
Prior, S.J., N.T. Jenkins, J. Brandauer, E.P. Weiss, J.M. Hagberg. Aerobic exercise training increases circulating IGFBP-1 concentration, but does not attenuate the reduction in circulating IGFBP-1 after a high-fat meal. Metabolism 61:310-316, 2012. PMCID:3227769.
Prior, S.J. Anti-hypertensive therapy and insulin sensitivity: regulation through the microcirculation? Hypertension Research 35:20-22, 2012. PMCID: 3380277.
Jenkins N.T., R.Q. Landers, S.R. Thakkar, X. Fan, M.D. Brown, Prior, S.J., E.E. Spangenburg, J.M. Hagberg. Prior Endurance Exercise Prevents Postprandial Lipemia-Induced Increases in Reactive Oxygen Species in Circulating CD31+ Cells. Journal of Physiology. 589:5539-5553, 2011. PMCID: 3240890.
Jenkins N.T., R.Q. Landers, Prior, S.J., N. Soni, E.E. Spangenburg, J.M. Hagberg. Effects of acute and chronic endurance exercise on intracellular nitric oxide and superoxide in circulating CD34+ and CD34- cells of endurance-trained and sedentary men. Journal of Applied Physiology 111:929-937, 2011.
Ryan, A.S., F.M. Ivey, S. Prior, G. Li, C.E. Hafer-Macko. Skeletal muscle hypertrophy and muscle myostatin reduction after resistive training in stroke survivors. Stroke 42:416-20, 2011. PMCID: 3026882.
Prior, S.J., A.P. Goldberg, A.S. Ryan. ADRB2 haplotype is associated with glucose tolerance and insulin sensitivity in obese postmenopausal women. Obesity 19:396-401, 2011. PMCID: 3056391.
Prior, S.J., M.J. McKenzie, L.J. Joseph, F.M. Ivey, R.F. Macko, C.E. Hafer-Macko, A.S. Ryan. Reduced skeletal muscle capillarization and glucose intolerance. Microcirculation 16:203-12, 2009. PMCID: 2990692
Ryan, A.S., R.F. Macko, F. Ivey, M. Peters, Prior, S.J., L.J. Joseph, C.E. Hafer-Macko. Plasma adiponectin levels are associated with insulin sensitivity in stroke survivors. Journal of Stroke and Cerebrovascular Diseases 18:214-220, 2009. PMCID: 2747076
McKenzie, M.J., S. Yu, Prior, S.J., R.F. Macko, C.E. Hafer-Macko. Hemi-paretic stroke alters vastus lateralis myosin heavy chain profiles between the paretic and non-paretic muscles. Research in Sports Medicine 17:17-27, 2009. PMCID: 2846402
Prior, S.J., S.M. Roth, X. Wang, C. Kammerer, I. Miljkovic-Gacic, C.H. Bunker, V.W. Wheeler, A.L. Patrick, J.M. Zmuda. Genetic and environmental influences on skeletal muscle phenotypes as a function of age and sex in large, multi-generational families of African Heritage. Journal of Applied Physiology 103:1121-7, 2007. *Received Editorial Focus. PMCID: 2811418
Prior, S.J., L.J.O. Joseph, J. Brandauer, L.I. Katzel, J.M. Hagberg, A.S. Ryan. Reduction in mid-thigh low-density muscle with aerobic exercise training and weight loss impacts glucose tolerance in older men. Journal of Clinical Endocrinology and Metabolism 92:880-886, 2007.
Prior, S.J., J.M. Hagberg, C.M. Paton, M.D. Brown, J.C. McLenithan, S.M. Roth. DNA sequence variation in the promoter region of the VEGF gene impacts VEGF gene expression and maximal oxygen consumption. American Journal of Physiology: Heart and Circulatory Physiology 290: H1848-1855, 2006.
Obesisan, T.O., C. Leeuwenburgh, R.E. Ferrell, D.A. Phares, J.A. McKenzie, Prior, S.J., J.M. Hagberg. C reactive protein genotype affects exercise training-induced changes in insulin sensitivity. Metabolism 55:453-460, 2006. PMCID: PMC2643021
Obesisan, T.O., C. Leeuwenburgh, T. Phillips, R.E. Ferrell, D.A. Phares, Prior, S.J., J.M. Hagberg. C-reactive protein genotypes affect baseline, but not exercise training-induced changes in, C-reactive protein levels. Arteriosclerosis, Thrombosis, and Vascular Biology 24:1874-1879, 2004. PMCID: PMC2643022
Prior, S.J., J.M. Hagberg, D.A. Phares, M.D. Brown, L. Fairfull, R.E. Ferrell, S.M. Roth. Sequence variation in hypoxia-inducible factor 1Î± (HIF1A): Association with maximal oxygen consumption. Physiological Genomics 15: 20-26, 2003.