HOME HELP SUBSCRIBE ARCHIVE SEARCH TABLE OF CONTENTS FEEDBACK EDITORIAL BOARD ABOUT DOC NEWS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

Services Email this article to a friend Similar articles in this journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Search for Related Content Social Bookmarking                What's this?

Metabolic Risk Tied to Fat Location

COMSTOCK/JUPITER IMAGES

The study, reported in the September issue of Journal of Clinical Investigation, indicates that obese mice that store excess energy solely in visceral adipose tissues—and keep fats from infiltrating the liver and muscle because of genetic modification they've undergone—can retain insulin sensitivity and other metabolic indicators within a normal range.

Through genetic engineering, the mice were missing leptin—an appetite- regulating hormone the adipose tissue secretes—and were overexpressing adiponectin—a protein hormone fat cells release to regulate metabolism of lipids and glucose. Most obese people have low levels of adiponectin and high levels of leptin, to which their body becomes increasingly desensitized. Although the mice in this study over-ate and became obese, they did not develop type 2 diabetes. In fact, the mice had better glucose control and serum triglycerides than their unmodified counterparts.

According to investigators, the modified mice stored excess energy in fat tissue instead of in the liver, heart, and muscle. Researchers propose that adiponectin appears to signal the body that it is starving, so that fats are not deposited in muscle and organs and instead are stored in adipose tissue.

The observation may explain why some obese people don't develop type 2 diabetes, while some of those with a body mass index (BMI) closer to normal have insulin insensitivity. The measurement of body fat may not be an adequate gauge of general metabolic health, the researchers conclude.

Kim JY, van de Wall E, Laplante M, et al.: Obesity-associated improvements in metabolic profile through expansion of adipose tissue. J Clin Invest 117: 2621–2637, 2007.[Medline]

CiteULike    Del.icio.us    Digg    Reddit    Technorati    What's this?

Services Email this article to a friend Similar articles in this journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Search for Related Content Social Bookmarking                What's this?