Mechanism of smoking-induced insulin resistance elucidated

September 17, 2012
Mechanism of smoking-induced insulin resistance elucidated
Smoking-induced insulin resistance, which improves with smoking cessation, may be due to activation of mammalian target of rapamycin, according to a study published online Sept. 10 in Diabetes.

(HealthDay)—Smoking-induced insulin resistance, which improves with smoking cessation, may be due to activation of mammalian target of rapamycin (mTOR), according to a study published online Sept. 10 in Diabetes.

To investigate the mechanism of smoking-induced insulin resistance, Bryan C. Bergman, Ph.D., from the University of Colorado Denver, and colleagues studied in 12 healthy sedentary nonsmokers and 10 smokers.

The researchers found that the smokers were less sensitive to insulin, but sensitivity improved after they stopped smoking for one or two weeks. The improvement was associated with normalized phosphorylation of insulin receptor substrate-1 (IRS-1) at serine 636. Treatment of muscle cells with nicotine reduced insulin sensitivity and was associated with increased phosphorylation of IRS-1 at serine 636. One of the two possible pathways known to stimulate IRS-1 phosphorylation, mTOR, was stimulated by nicotine; mTOR also prevented IRS-1 phosphorylation during and normalized insulin sensitivity when inhibited.

"These data indicate nicotine induces in skeletal muscle by activating mTOR," Bergman and colleagues conclude. "Therapeutic agents designed to oppose skeletal muscle mTOR activation may prove a novel strategy for individuals who are at increased risk of diabetes and cardiovascular disease because they cannot stop smoking or are exposed to secondhand smoke."

Explore further: Improving obesity-induced insulin sensitivity

More information: Abstract
Full Text (subscription or payment may be required)

Related Stories

Improving obesity-induced insulin sensitivity

June 1, 2012
In recent years, a growing body of evidence has linked inflammation to the development of insulin resistance. In insulin resistance, the hormone insulin is less effective in promoting glucose uptake from the bloodstream into ...

Fewer mitochondria in offspring of parents with diabetes

March 26, 2012
(HealthDay) -- Normal-weight, insulin-resistant individuals whose parents have type 2 diabetes have fewer mitochondria in their muscles due to lower expression of lipoprotein lipase (LPL), according to a study published in ...

Insulin resistance cut-off established from clamp data

April 23, 2012
(HealthDay) -- Cut-offs for predicting insulin resistance based on hyperinsulinemic-euglycemic clamp data and routinely measured clinical and biochemical variables have been determined, according to a study published online ...

Recommended for you

Personalized blood sugar goals can save diabetes patients thousands

December 11, 2017
A cost analysis by researchers at the University of Chicago Medicine shows treatment plans that set individualized blood sugar goals for diabetes patients, tailored to their age and health history, can save $13,546 in health ...

Kidney disease increases risk of diabetes, study shows

December 11, 2017
Diabetes is known to increase a person's risk of kidney disease. Now, a new study from Washington University School of Medicine in St. Louis suggests that the converse also is true: Kidney dysfunction increases the risk of ...

Type 2 diabetes is not for life

December 5, 2017
Almost half of the patients with Type 2 diabetes supported by their GPs on a weight loss programme were able to reverse their diabetes in a year, a study has found.

Skipping breakfast disrupts 'clock genes' that regulate body weight

November 30, 2017
Irregular eating habits such as skipping breakfast are often associated with obesity, type 2 diabetes, hypertension and cardiovascular disease, but the precise impact of meal times on the body's internal clock has been less ...

Type 2 diabetes has hepatic origins

November 28, 2017
Affecting as many as 650 million people worldwide, obesity has become one of the most serious global health issues. Among its detrimental effects, it increases the risk of developing metabolic conditions, and primarily type ...

Critical link between obesity and diabetes has been identified

November 28, 2017
UT Southwestern researchers have identified a major mechanism by which obesity causes type 2 diabetes, which is a common complication of being overweight that afflicts more than 30 million Americans and over 400 million ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.