Adipose tissue abdominal

Insulin resistance occurs when the normal response to a given amount of insulin is reduced. Resistance of liver to the effects of insulin results in inadequate suppression of hepatic glucose production insulin resistance of skeletal muscle reduces the amount of glucose taken out of the circulation into skeletal muscle for storage and insulin resistance of adipose tissue results in impaired suppression of lipolysis and increased levels of free fatty acids. Therefore, insulin resistance is associated with a cluster of metabolic abnormalities including elevated blood glucose levels, abnormal blood lipid profile (dyslipidemia), hypertension, and increased expression of inflammatory markers (inflammation). Insulin resistance and this cluster of metabolic abnormalities is strongly associated with obesity, predominantly abdominal (visceral) obesity, and physical inactivity and increased risk for type 2 diabetes, cardiovascular and renal disease, as well as some forms of cancer. In addition to obesity, other situations in which insulin resistance occurs includes... 

Data for superficial adipose tissue are the means for six different depots, those for intermuscular adipose tissue are the mean for three different depots, and those for intra-abdominal adipose tissue are the mean for four different depots. The percentages are remarkably similar. 

Crandall DL, Busier DE, Novak TJ, Weber, Krai JG. Identification of estrogen receptor beta RNA in human breast and abdominal Subcutaneous adipose tissue, Biochem. Biophys. Res. Commun. 248, 523-526, 1998. 

Adipose tissue, which consists of adipocytes (fat cells) (Fig. 23-16), is amorphous and widely distributed in the body under the skin, around the deep blood vessels, and in the abdominal cavity. It typically makes up about 15% of the mass of a young adult human, with approximately 65% of this mass in the form of triacylglycerols. Adipocytes are metabolically very active, responding quickly to hormonal stimuli in a metabolic interplay with the liver, skeletal muscles, and the heart. 

Takami K, Takeda N, Nakashima K, Takami R, Hayashi M, Ozeki S, Yamada A, Kokubo Y, Sato M, Kawachi S, Sasaki A, Yasuda K. Effects of dietary treatment alone or diet with voglibose or glyburide on abdominal adipose tissue and metabolic abnormalities in patients with newly diagnosed type 2 diabetes. Diabetes Care 2002 25(4) 658-62. 

Fig. 20.5. Femoral nerve dissection. The motor and sensory branches of the femoral nerve are exposed. The mouse is supine and the right hip is shown (forceps are retracting the abdominal wall, A, P, M, L are anterior, posterior, medial, and lateral respectively, H is hamstring muscles). Some adipose tissue has been removed for clarity. The motor branch of the femoral nerve innervates the quadriceps (Q). The sensory branch becomes the saphenous nerve, which runs adjacent to the saphenous vein (Saph) on the medial side of the thigh. Dissecting the nerve where the tick marks provides a reasonable length of nerve to work with. Note the sensory branch sometimes runs as two fascicles and both should be taken to get reproducible counts. The scale bar is 2 mm. (Color figure is available online).

DEHP is lipophilic and tends to migrate into adipose deposits. Since it is cleared from these deposits slowly, analysis of fat tissues probably provides the best test for previous exposure to this plasticizer. Analysis of human abdominal adipose tissues from accident victims indicated that DEHP was present in these tissues at a concentration of 0.3-1.0 ppm (Mes et al. 1974). DEHP was also identified in 48% of the adipose tissue specimens from cadavers autopsied in 1982 as part of the Human Adipose Tissue Survey from the National Human Monitoring Program (EPA 1989b). Neither study contained data on DEHP exposure history of the subjects, however, and there is no information regarding correlation of adipose tissue concentrations with DEHP exposure concentration and duration. 

Rieserus, U., Berglund, L., and Vessby, B. 2001. Conjugated linoleic acid (CLA) reduced abdominal adipose tissue in obese middle-aged men with signs of metabohc syndrome, a randomized controlled trial. Int. J. Obesity, 25,1129-1135. 

Obesity, and particularly the accumulation of abdominal fat, creates an inflammatory milieu that is the key driver of insulin resistance and CVD (44 6). In the normal state, adipose tissue coordinately regulates the synthesis and secretion of peptides... 

Kekes-Szabo, T, Hunter, G. R., Nyikos, I., Williams, M., Blaudeau, T., and Snyder, S. (1996), Anthropometric equations for estimating abdominal adipose tissue distribution in women, fnt. J- OhesiYy 20, 753-758. 

D. Langin, C. Holm, and V. Large, The presence of a catalytically inactive form of hormone-sensitive lipase is associated with decreased lipolysis in abdominal subcutaneous adipose tissue of obese subjects. Diabetes, 2003, 52, 1417—1422. 

L. Enevoldsen, B. Stallknecht, (. Langfort, L. Petersen, C. Holm, T. Ploug, and H. Galbo, The effect of exercise training on hormone-sensitive lipase in rat intra-abdominal adipose tissue and muscle, J. Physiol., 2001, 536, 871-877. 

A BMI greater than 28 is an independent risk factor (3 times higher than the general population) for cardiovascular diseases (Chapter 20), diabetes mellitus type 2 (Chapter 22), and stroke. The prevalence of obesity-associated morbidity depends on the location of fat distribution in the body. Intra-abdominal or visceral fat deposits are associated with higher health risks than gluteofemoral adipose tissue fat accumulation. 

Adipose Tissue Androgens promote truncal-abdominal fat deposition and favor development of upper body obesity. In contrast to gluteofemoral (lower body) fat, upper body fat accumulation, particularly visceral fat, is characterized by an increase in fat cell size, increased lipoprotein lipase (LPL) activity, enhanced lipolysis, and reduced response to the antilipolytic effect of insulin. This explains why androgen-dominated states favor insulin resistance. 

The term visceral adipose tissue (VAT) refers to fat cells located within the abdominal cavity and includes omental, mesenteric, retroperitoneal, and perinephric adipose tissue. VAT has been shown to correlate with insuhn resistance and explain much of the variation in insuhn resistance seen in a population of African-Americans. Visceral adipose tissue represents 20% of fat in men and 6% of fat in women. This fat tissue has been shown to have a higher rate of lipolysis than subcutaneous fat, resulting in an increase in free fatty acid production. These fatty acids are released into the portal circulation and drain into the liver, where they stimulate the production of very-low-density lipoproteins and decrease insuhn sensitivity in peripheral tissues. VAT also produces a number of cytokines which cause insulin resistance. These factors drain into the portal circulation and reduce insulin sensitivity in peripheral tissues. ... 

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