Professor and Head David Bernlohr

This group is involved in two main areas of research that use MSI resources.

• Adipose Biology and Obesity Linked Insulin Resistance: A major research study in the laboratory focuses on the metabolic relationships between obesity and insulin action. This laboratory specifically examines cytoplasmic fatty acid binding proteins and their role(s) in mediating fatty acid metabolism in adipocytes and macrophages, particularly leukotriene synthesis. Using a combination of biochemical, biophysical and molecular methodologies, the laboratory studies the synthesis of inflammatory lipids in macrophages and other cells. Importantly, animal models either null or transgenic for fatty acid binding proteins reveal that intracellular lipid metabolism control the synthesis and secretion of adipose-derived cytokines (adipokines) linked to glucose and lipid metabolism in muscle and liver. Using a drug discovery approach, small molecule inhibitors of FABPs have been identified that exhibit anti-inflammatory properties in macrophages. Such studies provide a framework for the analysis of obesity-linked insulin resistance.
• Oxidative Stress, Mitochondrial Function, and Senescence: Plasma membrane lipids undergo chemical and enzymatic peroxidation leading to the generation of a,b-unsaturated aldehydes such as 4-hydorxynonenal. Such reactive lipids form chemical cross links with proteins and DNA and are implicated in oxidative diseases such as psoriasis, aging, macular degeneration and type 2 diabetes. Moreover, such protein modification, termed carbonylation, leads to system-wide changes in cellular function including mitochondrial respiration and signal transduction. In this project, the Bernlohr laboratory examines antioxidant defense systems operable in adipose tissue and their regulation by pro-inflammatory cytokines. Importantly, loss of antioxidant defenses in type 2 diabetes leads to increased protein carbonylation and decreased mitochondrial function. This increase in carbonylation leads to the development of senescence which may underlie many of the biochemical events linked to insulin resistance and lead to new insight in age and nutrient-dependent diseases.