Gene expression profile in obesity and type 2 diabetes mellitus.

Obesity is an important component of metabolic syndrome X and predisposes to the development of type 2 diabetes mellitus. The incidence of obesity, type 2 diabetes mellitus and metabolic syndrome X is increasing, and the cause(s) for this increasing incidence is not clear. Although genetics could play an important role in the higher prevalence of these diseases, it is not clear how genetic factors interact with environmental and dietary factors to increase their incidence. We performed gene expression profile in subjects with obesity and type 2 diabetes mellitus with and without family history of these diseases. It was noted that genes involved in carbohydrate, lipid and amino acid metabolism pathways, glycan of biosynthesis, metabolism of cofactors and vitamin pathways, ubiquitin mediated proteolysis, signal transduction pathways, neuroactive ligand-receptor interaction, nervous system pathways, neurodegenerative disorders pathways are upregulated in obesity compared to healthy subjects. In contrast genes involved in cell adhesion molecules, cytokine-cytokine receptor interaction, insulin signaling and immune system pathways are downregulated in obese. Genes involved in signal transduction, regulation of actin cytoskeleton, antigen processing and presentation, complement and coagulation cascades, axon guidance and neurodegenerative disorders pathways are upregulated in subjects with type 2 diabetes with family history of diabetes compared to those who are diabetic but with no family history. Genes involved in oxidative phosphorylation, immune, nervous system, and metabolic disorders pathways are upregulated in those with diabetes with family history of diabetes compared to those with diabetes but with no family history. In contrast, genes involved in lipid and amino acid pathways, ubiquitin mediated proteolysis, signal transduction, insulin signaling and PPAR signaling pathways are downregulated in subjects with diabetes with family history of diabetes. It was noted that genes involved in inflammatory pathway are differentially expressed both in obesity and type 2 diabetes. These results suggest that genes concerned with carbohydrate, lipid and amino acid metabolic pathways, neuronal function and inflammation play a significant role in the pathobiology of obesity and type 2 diabetes.

Elevated butyrylcholinesterase and acetylcholinesterase may predict the development of type 2 diabetes mellitus and Alzheimer's disease.

Plasma levels of C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and lipid peroxides are elevated and concentrations of endothelial nitric oxide (eNO) decreased in type 2 diabetes mellitus and Alzheimer's disease. This suggests that both these diseases are low-grade systemic inflammatory conditions and are closely associated with each other. Recent studies revealed that plasma and tissue concentrations of enzymes butyrylcholinesterase and acetylcholinesterase are elevated in type 2 diabetes and Alzheimer's disease. Acetylcholine has anti-inflammatory actions. Hence, elevated butyrylcholinesterase and acetylcholinesterase concentrations will lead to a decrease in the levels of acetylcholine that could trigger the onset of low-grade systemic inflammation seen in type 2 diabetes and Alzheimer's disease. In view of this, we propose that butyrylcholinesterase and acetylcholinesterase will not only serve as therapeutic targets but also may serve as markers to predict the development of type 2 diabetes mellitus and Alzheimer's disease.