Body Fat in Obese May Be Toxic

Insulin resistance and chronic inflammation lead to diabetes and heart disease

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Some obese patients develop conditions such as heart disease and diabetes, while others manage to avoid such chronic diseases. That may be because all obesity is not the same.

UC Davis Health System researchers examined the body fat of people with metabolic syndrome, a condition characterized by high blood pressure, high- fasting blood-sugar levels, excess abdominal fat and abnormal cholesterol levels. They discovered the fat cells released biomarkers linked to insulin resistance and chronic inflammation, which can lead to diabetes and heart disease.

"Lose weight and exercise to avoid metabolic syndrome."

Ishwarlal Jialal, senior author and UC Davis professor of endocrinology, diabetes and metabolism, said the study showed that not all obesity is the same, and that some body fat may actually be toxic.  He said they have shown that the dysfunction in the fat of those with metabolic syndrome is a high risk condition for the obese. The study is the first to identify fat as a contributing source of biomarkers in those with metabolic syndrome.

Researchers took biopsies of fat from the buttocks of 65 patients. Of those, 39 were newly diagnosed with metabolic syndrome and 26 were obese. They also took measurements including waist circumference and body mass index, and tests including fasting glucose to estimate insulin resistance and blood pressure.

Investigators measured 11 biomarkers for diabetes and cardiovascular disease, and then counted the number of macrophages in the fat tissue. Macrophages are immune cells that form structures around fat cells that have outgrown their blood supply and died. Their presence indicates inflammatory response found in heart disease.

Jialal said the data suggested intrinsic defects in body fat. In addition it was found that endothelial prognitor cells, which line blood vessels and are used as a gauge of heart health, are relevant to an increased risk of developing diabetes and heart disease.

Metabolic syndrome can be reversed through exercise and weight loss, but other treatment may be needed. Jialal added that researchers need to address the dysfunction of fat cells, using existing or novel drug therapies to block the production of damaging biomarkers.

"Once people have cardiovascular disease or diabetes, it's too late and far more expensive given the complications that ensue. Metabolic syndrome is the antecedent. This is where we need to intervene,"  Jialal said.

The research was published in the Journal of Clinical Endocrinology & Metabolism.

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Review Date: 
August 29, 2011
Last Updated:
August 31, 2011