Human Mesenteric Adipose Tissue Plays Unique Role Versus Subcutaneous and Omental Fat in Obesity Related Diabetes

Abstract

Background/Aims: Obesity is a common and rapidly growing health problem today. Obesity is characterized by the increase of body fat and an excess of total body fat and, in particular, visceral fat accumulation, is considered to be a risk factor for type 2 diabetes mellitus. To determine whether the malfunction of the mesenteric adipose tissue plays an important role in the diabetic related metabolic syndrome, in this study, lipolysis and gene expression in the subcutaneous, omental and mesenteric adipose tissue of the diabetic subjects were evaluated. Methods: Lipolysis and real time PCR were utilized to determine adipocyte function. Results: Basal adipose tissue glycerol release is higher in diabetics than that of the non diabetics in all three fat depots. Isoproterenol (ISO) significantly increases glycerol release in subcutaneous, omental and mesenteric adipose tissues of non diabetic subjects but it stimulated glycerol release was significantly impaired in all three fat depots of the diabetic subjects. Gene expression studies indicate that leptin, Peroxisome proliferator-activated receptor-gamma (PPAR-gamma), Fatty acid translocase (FAT/CD36) and 11β-hydroysteroid dehydrogenase (HSD) gene expression were significantly up regulated in the mesenteric adipose tissue of the diabetic patients. Conclusion: Human mesenteric adipose tissue in obese diabetic subjects has high basal glycerol release and impaired isoproterenol stimulated glycerol release. The obesity-related gene expressions in the mesenteric adipose tissue are up regulated, suggesting that the alterations of these genes in mesentery adipose depot may play a critical role in insulin resistance of type 2 diabetes and metabolic syndrome.

The pyloric caeca area is a major site for IgM+ and IgT+ B cell recruitment in response to oral vaccination in rainbow trout

“…Although the presence of immune cells in diverse adipose structures has been reported in humans and other mammalian models [31], the immune reactions and how their regulation occur in the various environments within the body have been only marginally appreciated in the past, despite the fact that there is a correlation between the presence of fatassociated lymphoid cells and inflammation in obesity [31]. Adipose tissue in mammals is generally separated into visceral and subcutaneous adipose tissue, being the visceral adipose tissue the one which is metabolically and immunologically more active [32]. In mammals, this visceral fat tissue refers to adipose within the peritoneal cavity, including depots such as the gonadal fat pad, the omentum, and the intestinal mesentery [33].…”

Fat Depot-Specific Differences in Angiogenic Growth Factor Gene Expression and Its Relation to Adipocyte Size in Cattle

“…In contrast, Higashiyama et al [19] showed that subcutaneous adipose tissue expressed higher levels of leptin mRNA than did omental adipose tissues in Wagyu steers. Both mesenteric and omental adipose tissues are classified as visceral fats, although Yang et al [47] showed that the expression of leptin mRNA in mesenteric adipose tissue was significantly higher than that of omental adipose tissue in humans. These results suggest that the expressional potency of leptin mRNA in mesenteric adipose tissue may be higher than that in omental adipose tissue.…”

Pathophysiology of Human Visceral Obesity: An Update

“…Although the number of cells from the stroma-vascular cell fraction that are committed to the adipocyte lineage appears to be quite similar among abdominal fat compartments, the number of macrophages expressing aP2 was found to be higher in omental than in subcutaneous fat cells, while being intermediate in the mesenteric fat depot (562). In diabetic subjects, CD36 and 11␤-HSD-1 expression were increased in mesenteric fat compared with subcutaneous and omental fat, suggesting that this depot may, indeed, play a role in the development of metabolic alterations (632). The activity of AMP kinase was found to be lower in both mesenteric and omental fat tissue compared with the subcutaneous depot of obese individuals, which was associated with increased expression of genes related to inflammation (185).…”

“…Cytosolic and microsomal triglyceride lipase activities were reported to be lower in mesenteric than in subcutaneous adipose tissue (388). Mesenteric fat was also shown to have higher basal lipolysis but blunted isoproterenol responsiveness compared with other depots in diabetic subjects (632). With regard to lipid uptake, in vivo data show that meal lipid uptake is similar in omental and mesenteric adipose tissue, suggesting that omental fat is representative of other visceral compartments for this particular parameter (236).…”