Navigation Links
Genes influence effectiveness of weight-loss drug
Date:9/30/2008

Bethesda, MD (Oct. 1, 2008) Obese patients with a specific genetic make-up lose more weight when taking the weight loss drug sibutramine and undergoing behavioral therapy compared to those without this genetic make-up, reports a new study in Gastroenterology, the official journal of the American Gastroenterological Association (AGA) Institute.

The obesity epidemic continues to be an increasingly global problem: an estimated 1.6 billion adults worldwide are overweight (body mass index [BMI]>25) and 400 million are obese (BMI>30). In addition, the incidences of diabetes and other debilitating diseases attributable to obesity continue to rise.

While there are numerous options for the treatment of obesity, this study examined sibutramine, a medication approved for the long-term treatment of obesity. The drug creates a feeling of fullness, prevents decline in metabolic rate associated with low calorie diets and causes weight loss, especially when combined with behavioral therapy. However, weight loss with the drug is highly variable. Therefore, a research team at the Mayo Clinic assessed the influence of specific markers of candidate genes controlling serotonergic and adrenergic mechanisms (α2A-receptor, 5-HTTLPR and GNβ3) on weight loss/body composition in response to sibutramine or placebo.

"We found significantly lower values for weight, BMI and proportion of body fat in patients taking sibutramine. The candidate gene variations provided useful markers of enhanced response to the drug," said Michael Camilleri, MD, AGAF, of the Mayo Clinic and lead author of the study. "Gene variations may help select obese patients who are more likely to experience improved outcome with this treatment. Since the different markers were present in almost 50 percent of patients, inclusion of screening for these genetic markers before prescribing the medication may even be cost-effective from a public health perspective."

In this randomized, double-blind, pharmacogenetic study, Dr. Camilleri and colleagues evaluated behavioral therapy and sibutramine (10 or 15 mg daily) or placebo for 12 weeks in 181 overweight or obese participants. They measured body weight, BMI, body composition, gastric emptying and genetic variation.

Study results showed that sibutramine at both doses, given in combination with behavioral therapy, caused significant weight loss (p = 0.009). The drug resulted in lower values for weight, BMI and proportion of body fat compared to placebo (p<0.01, p<0.001 and p=0.05, respectively). Weight loss at four weeks was a predictor of weight loss achieved at 12 weeks.

There was a statistically significant gene-by-dose interaction for GNβ3 genotype. This gene determines the function of G proteins, which are involved in translating the message from surface receptors that bind the transmitters serotonin and norepinephrine (e.g. of cells controlling appetite). Those surface receptors are indirectly influenced by sibutramine, which blocks the reuptake of the two transmitters. For each candidate gene, treatment effects were observed at 12 weeks (p<0.017) for all specific genotype variants. The research showed gene pairs (e.g. for GNβ3and α2A-receptor) resulted in greater sibutramine treatment effects on weight (both p<0.002). However, there was no evidence of synergism between combinations of two genotypes on the response to sibutramine therapy compared to the effect on weight loss associated with individual genotypes.

"Our results suggest the genetic make-up of patients could predispose their responsiveness to a drug. This could have important implications for the future of personalized molecular-based or individualized medicine," added Dr. Camilleri. As new and exciting research like this study continues into the causes, prevention and treatments for obesity, the role played by the GI tract is becoming more defined. This understanding has the potential to lead to novel endoscopic, pharmacological and nutritional therapies for obesity as well as changes in policies and societal practices related to obesity.


'/>"/>

Contact: Alissa Cruz
media@gastro.org
301-272-1603
American Gastroenterological Association
Source:Eurekalert

Related medicine news :

1. Genes affect weight loss drug effectiveness
2. UNC study: Parenting can override effect of genes in how babies respond to stress
3. Type 1 diabetes may result from good genes behaving badly
4. Nanomedical approach targets multiple cancer genes, shrinks tumors more effectively
5. Genesis Pharmaceuticals Received New Purchase Orders Worth $12 Million
6. The first autism disease genes
7. Neurogenesis in the adult brain: The association with stress and depression
8. Beyond PTEN: Alternate genes linked to breast, thyroid and kidney cancer predisposition
9. Researchers Find Genes That Influence West Nile Virus
10. ThermoGenesis Announces 10 New BioArchive(R) System Distributors
11. Genesis Pharmaceuticals Announces New Board Member and Forms Committees
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/25/2016)... ... 25, 2016 , ... As a lifelong Southern Californian, Dr. Omkar Marathe earned ... the David Geffen School of Medicine at UCLA. He trained in Internal Medicine at ... fellowship in hematology/oncology at the UCLA-Olive View-Cedars Sinai program where he had the opportunity ...
(Date:6/25/2016)... ... , ... On Friday, June 10, Van Mitchell, Secretary of the Maryland Department ... in recognition of their exemplary accomplishments in worksite health promotion. , The Wellness at ... Wellness Symposium at the BWI Marriott in Linthicum Heights. iHire was one of 42 ...
(Date:6/24/2016)... ... June 24, 2016 , ... A recent article published June 14 ... The article goes on to state that individuals are now more comfortable seeking to ... operations such as calf and cheek reduction. The Los Angeles area medical group, Beverly ...
(Date:6/24/2016)... ... June 24, 2016 , ... June 19, 2016 is ... associated with chronic pain and the benefits of holistic treatments, Serenity Recovery Center ... suffering with Sickle Cell Disease. , Sickle Cell Disease (SCD) is a disorder of ...
(Date:6/24/2016)... ... 2016 , ... The Pulmonary Hypertension Association (PHA) learned during ... two significant new grants to support its work to advance research and patient ... recognizing patients, medical professionals and scientists for their work in fighting pulmonary hypertension ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... 24, 2016  Global Blood Therapeutics, Inc. (GBT) (NASDAQ: ... novel therapeutics for the treatment of grievous blood-based ... closing of its previously announced underwritten public offering ... public offering price of $18.75 per share. All ... by GBT. GBT estimates net proceeds from the ...
(Date:6/24/2016)... DUBLIN , June 24, 2016 ... and Markets has announced the addition of the ... their offering. ... products and provides an updated review, including its applications ... covering the total market, which includes three main industries: ...
(Date:6/24/2016)... , June 24, 2016 The Academy ... of recommendations that would allow biopharmaceutical companies ... with entities that make formulary and coverage decisions, a ... "value" of new medicines. The recommendations address ... not appear on the drug label, a prohibition that ...
Breaking Medicine Technology: