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WEST LAFAYETTE, Ind. - Researchers have uncovered new evidence suggesting factors other than genes could cause obesity, finding that genetically identical cells store widely differing amounts of fat depending on subtle variations in how cells process insulin. Learning the precise mechanism responsible for fat storage in cells could lead to methods for controlling obesity. "Insights from our study also will be important for understanding the precise roles of insulin in obesity or Type II diabetes, and to the design of effective intervention strategies," said Ji-Xin Cheng, an assistant professor in Purdue University's Weldon School of Biomedical Engineering and Department of Chemistry. Findings indicate that the faster a cell processes insulin, the more fat it stores.

Conjugated linoleic acid promotes human adipocyte insulin resistance through NFkappaB-dependent cytokine production. Chung S, Brown JM, Provo JN, Hopkins R, McIntosh MK. J Biol Chem. 2005 Nov 18;280(46):38445-56. Epub 2005 Sep 9. PMID: 16155293 doi: 10.1074/jbc.M508159200 Collectively, these data demonstrate for the first time that trans-10, cis-12 CLA promotes NFkappaB activation and subsequent induction of IL-6, which are at least in part responsible for trans-10, cis-12 CLA-mediated suppression of peroxisome proliferator-activated receptor gamma target gene expression and insulin sensitivity in mature human adipocytes. In summary, our in vitro data demonstrate that a physiological level of trans-10, cis-12 CLA activates NFκB- and ERK1/2-dependent cytokine production, which together suppress PPARγ and Glut4 levels and lead to impaired glucose uptake. Studies are currently under way examining 1) how CLA regulates PPARγ and the expression of its target genes, 2) the specific signaling role of SV cells and adipocytes in mediating the TG-lowering actions of CLA, and 3) the CLA-induced, upstream signal that activates NFκB and ERK1/2.

"My goal is to gather the basic science and apply it to nutrition - NUTRIGENOMICS. What do I mean? How does what we eat signal our genes in the nucleus. By our food choices, we are sending different signals to our genes. High carbohydrate and high fructose intake signals it is summer time and winter is coming -- grow and store the energy (insulin). High fat, low carbohydrate diet with calorie restriction signals our genes that winter is here -- use the stored energy, repair the genes, and slow down growth (i.e. Sirt1/Foxo pathway). The Sirt1/FoxO1 pathway is important as it aids in repairing DNA. Damaged DNA can lead to uncontrolled cellular replication (i.e. cancers). The immune system (phagocytes) has a mechanism to remove old and unwanted cells called apoptosis (cellular death). "

A Role of DNA-PK for the Metabolic Gene Regulation in Response to Insulin Roger H.F. Wong, Inhwan Chang, Carolyn S.S. Hudak, Suzanne Hyun, Hiu-Yee Kwan, Hei Sook Sul Cell 20 March, 2009 Volume 136, Issue 6, p1056 doi:10.1016/j.cell.2008.12.040    

What is C-reactive protein (CRP)? It is a blood-borne protein that originates in the liver and serves as an index of the body's inflammatory state. It is triggered by yet another inflammatory signal molecule, interleukin-6. What triggers this cascade of inflammatory markers? Any inflammatory stimulus, such as being overweight, lack of exercise, vitamin D deficiency, viral illness no matter how trivial, any inflammatory disease like arthritis, small LDL, high triglycerides, poor diet rich in processed foods, resistance to insulin, any injury, incipient diabetes, hidden cancer, lack of education (no kidding), etc.

Vitamin D and calcium insufficiency-related chronic diseases: molecular and cellular pathophysiology. Peterlik M, Cross HS. Eur J Clin Nutr. 2009 Dec;63(12):1377-86. Epub 2009 Sep 2. PMID: 19724293 doi:10.1038/ejcn.2009.105 A compromised vitamin D status, characterized by low 25-hydroxyvitamin D (25-(OH)D) serum levels, and a nutritional calcium deficit are widely encountered in European and North American countries, independent of age or gender. Both conditions are linked to the pathogenesis of many degenerative, malignant, inflammatory and metabolic diseases. Studies on tissue-specific expression and activity of vitamin D metabolizing enzymes, 25-(OH)D-1alpha-hydroxylase and 25-(OH)D-24-hydroxylase, and of the extracellular calcium-sensing receptor (CaR) have led to the understanding of how, in non-renal tissues and cellular systems, locally produced 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) and extracellular Ca2+ act jointly as key regulators of cellular proliferation, differentiation and function. Impairment of cooperative signalling from the 1,25-(OH)2D3-activated vitamin D receptor (VDR) and from the CaR in vitamin D and calcium insufficiency causes cellular dysfunction in many organs and biological systems, and, therefore, increases the risk of diseases, particularly of osteoporosis, colorectal and breast cancer, inflammatory bowel disease, insulin-dependent diabetes mellitus type I, metabolic syndrome, diabetes mellitus type II, hypertension and cardiovascular disease. Understanding the underlying molecular and cellular processes provides a rationale for advocating adequate intake of vitamin D and calcium in all populations, thereby preventing many chronic diseases worldwide.

Researchers at the University of California, Berkeley, have identified a gene that plays a critical regulatory role in the process of converting dietary carbohydrates to fat. In a new study, they disabled this gene in mice, which consequently had lower levels of body fat than their normal counterparts, despite being fed the equivalent of an all-you-can-eat pasta buffet. The authors of the study, to be published in the March 20 issue of the journal Cell, say the gene, called DNA-PK, could potentially play a role in the prevention of obesity related to the over-consumption of high-carbohydrate foods, such as pasta, rice, soda and sugary snacks..