Born and raised in California, Dr. Adams attended FresnoStateUniversity where he earned a B.A. in Biology and a Minor in Chemistry. His interest in comparative physiology led to an M.S. in Marine Sciences at UC, Santa Cruz, where he worked in the lab of Dr. Dan Costa to study metabolic and renal adaptations associated with natural long-term fasting in seals. In the group of Dr. Jack Odle at the University of Illinois, his Ph.D. research in Nutritional Sciences explored the regulation of intracellular fatty acid trafficking and combustion in the neonatal piglet model. This work helped highlight the importance of hydrolysis of acetyl-CoA (e.g., acetogenesis) as a common biochemical fate of lipids in the cell. During an NSF/NATO Postdoctoral Fellowship with Dr. Fausto G. Hegardt at the University of Barcelona, he investigated the molecular regulation of ketone body production through investigations of postnatal gene expression of the key ketogenic enzyme mitochondrial hydroxymethylglutaryl-CoA synthase (HMG-CoA synthase).As a postdoctoral investigator with Dr. J. Denis McGarry at UT Southwestern Medical School in Dallas, Dr. Adams evaluated the potential role of carnitine palmitoyltransferase (CPT) in male reproductive function through analysis of expression and activity levels in developing germ cells, and he built a variety of CPT adenoviral delivery tools used to study fatty acid metabolism in muscle and liver. Prior to joining the WHNRC, Dr. Adams worked in the biotechnology and pharmaceutical research arena for over seven years, focusing on molecular and biochemical events associated with tissue thermogenesis and energy expenditure.Research included studies of unique mitochondrial uncoupling proteins (UCPs) and carrier proteins implicated in mitochondrial metabolism, characterization of genes and metabolic pathways involved in brown adipose tissue (BAT) heat production and nutrient utilization, and evaluation of food intake physiology through exploration of the activities of gut hormones such as peptide YY (PYY) and ghrelin.His recent work builds upon this background to better understand the physiological networks that shape metabolic status.
The laboratory of Dr. Adams investigates the etiology of obesity and associated disorders such as diabetes, determines how specific foods and food components modify these parameters, and searches for molecular biomarkers reflective of a healthy or disordered metabolism.Current Research areas include:
·Interrelationships between fat tissue, metabolic status, and the peripheral nervous system--Interestingly, there are a number of proteins uniquely co-expressed in both peripheral nerves and fat cells, suggestive of shared function and potential cross-talk between fat and afferent neural circuits relaying information to the brain.Studies are underway to test how expression of these unusual “fat-neuron” genes impact and are influenced by obesity and specific metabolite and hormone cues.
·Identification of New Markers of Diabetes--Unfortunately, most people at risk of developing type 2 diabetes mellitus are not identified early enough to thwart disease through nutritional or other interventions.The lab is leading a collaborative effort involving scientists at the WHNRC, UC Davis, the University of Alabama at Birmingham, the University of Ottawa, and CaseWestern ReserveUniversity to identify hundreds of metabolites and small molecules in biofluids such as blood plasma to unmask patterns indicative of insulin resistance and poor blood glucose control.Efforts also focus on muscle-specific metabolites that correlate with markers of blood glucose homeostasis and that reflect fat metabolism.
·Obesity- and Diabetes-Associated Inflammation in Fat Tissue and Effects of Specific Foods and Metabolites to Modulate Inflammation and Metabolic Profiles--Obesity is a major risk factor for development of metabolic disease, and it is now believed that inflammation is at the heart of this phenomenon.Type 2 diabetes is also in part a disease of increased inflammation.One line of research examines how obesity and diet correlate with fat tissue infiltration of macrophages.Other work is determining whether certain metabolites that accumulate in the blood of type 2 diabetics evoke a pro-inflammatory response associated with insulin resistance.
·The team has identified two cellular proteins that share the unusual property of abundant co-expression in fat cells and in neurons involved with signaling information from peripheral tissues to the brain.Such a pattern suggests that these otherwise quite different biological systems share important functional attributes.The genes encoding these proteins are responsive to the critical metabolic regulator PPAR, potentially highlighting a mechanism by which metabolic status can be sensed by or alter activities in peripheral nerves.
·Working with groups from the WHNRC, UC Davis, the University of Ottawa, the University of Alabama Birmingham, and Case Western Reserve University, metabolite patterns indicative of poor blood sugar control have been identified by leveraging the emerging field of metabolomics.These studies have shown that in type 2 diabetics, there are increased plasma concentrations of certain acylcarnitines and amino acid moieties that reflect inefficient fatty acid ß-oxidation (“fat burning”) and abnormal amino acid catabolism.The latter may impact the primary energy-generating process in the cell, the tricarboxylic acid cycle.
·Inflammation in fat tissue is an important contributor to poor metabolic health, but the specific nutrients and foods that can impact immune cell (macrophage, e.g.) infiltration into adipose tissue remains unclear.The lab has identified a new marker of macrophage infiltration in fat, termed CD11d, and has found evidence that the degree of macrophage infiltration tracks body weight gain differences in lean-to-obese mice.The latter provides evidence that as energy storage requirements increase, macrophage activities in fat likely play a normal, non-pathological role in adipose tissue remodeling.Further, studies using dairy protein/carbohydrate in a high fat obesity-promoting diet showed that dairy components thwart obesity and adipose inflammation--this indicates that specific diet factors can have a profound effect on these processes.
Selected Articles & Patent Applications
1.A.P. Thomas, T.N. Dunn, P.J. Oort, M. Grino, and S.H. Adams.Inflammatory phenotyping identifies CD11d as a gene markedly induced in white adipose tissue in obesity.J. Nutr., in press.