SRC-1 Gene Variants Linked To Human Obesity

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From The Baylor College of Medicine…..

BaylorCollegeMaintaining a healthy body weight is no simple matter. A better understanding of how the body regulates appetite could help tip the scale toward the healthy side. Contributing toward this goal, a team led by researchers at Baylor College of Medicine and the University of Cambridge reports in the journal Nature Communications that the gene SRC-1 affects body weight control by regulating the function of neurons in the hypothalamus – the appetite center of the brain.

Mice lacking the SRC-1 gene eat more and become obese. SRC-1 also seems to be involved in regulating human body weight. The researchers identified in severely obese children 15 rare SRC-1 genetic variants that disrupt its function. When mice were genetically engineered to express one of these variants, the animals ate more and gained weight.

“The protein called steroid receptor coactivator-1 (SRC-1) is known to participate in the regulation of body weight, but its precise role is not clear,” said co-corresponding author Dr. Yong Xu, associate professor of pediatrics and of molecular and cellular biology and a researcher at the USDA/ARS Children’s Nutrition Research Center at Baylor College of Medicine and Texas Children’s Hospital. “Here we explored the role of SRC-1 in the hypothalamus, a brain area that regulates appetite.”

The researchers discovered that SRC-1 is highly expressed in the hypothalamus of mice, specifically in neurons that express the Pomc gene. Pomc neurons are known to regulate appetite and body weight.

Further experiments showed that SRC-1 is involved in regulating the expression of Pomc gene in these cells. When Xu and his colleagues deleted the SRC-1 gene in Pomc neurons, the cells expressed less Pomc and the mice ate more and became obese.

The researchers also explored whether SRC-1 also would play a role in regulating human body weight.

“We had identified a group of severely obese children carrying rare genetic variants in the SRC-1 gene,” said co-corresponding author Dr. I. Sadaf Farooqi, professor of metabolism and medicine in the Department of Clinical Biochemistry at the University of Cambridge and Wellcome Trust Principal Research Fellow.

Working together, Xu, Sadaf Farooqi and their colleagues found that many of the SRC-1 variants in the obese children produced dysfunctional proteins that disrupted the normal function of SRC-1. On the other hand, SRC-1 variants in healthy individuals did not disrupt SRC-1 function.

saladheartsmallFurthermore, mice genetically engineered to express one of the human SRC-1 genetic variants found in obese children ate more and gained weight. This is the first report of SRC-1 playing a role in the hypothalamus in the context of body weight control.

“By providing evidence that bridges basic and genetic animal studies and human genetic data, we have made the case that SRC-1 is an important regulator of body weight,” Xu said.

Other contributors to this work include Yongjie Yang, Agatha A. van der Klaauw, Liangru Zhu, Tessa M. Cacciottolo, Yanlin He, Lukas K.J. Stadler, Chunmei Wang, Pingwen Xu, Kenji Saito, Antentor Hinton Jr, Xiaofeng Yan, Julia M. Keogh, Elana Henning, Matthew C. Banton, Audrey E. Hendricks, Elena G. Bochukova, Vanisha Mistry, Katherine L. Lawler, Lan Liao, Jianming Xu, Stephen O’Rahilly, Qingchun Tong, UK10K consortium, Inês Barroso and Bert W. O’Malley. The authors are affiliated with one or more of the following institutions: Baylor College of Medicine; University of Cambridge Metabolic Research Laboratories; Wellcome Trust-MRC Institute of Metabolic Science; Huazhong University of Sciences & Technology, China; Wellcome Sanger Institute, Cambridge; University of Colorado – Denver and University of Texas Health Science Center at Houston.

For a complete list of the sources of financial support for this project, visit this link.

 

The Success Of New Gene Therapy For Heart Patients

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What is your opinion about this article from PRWeb written by Bel Marra Health?

heartBel Marra Health, who offers high-quality, specially formulated vitamins and nutritional supplements, has reported on new research that has shown the success of the first ever biological pacemaker that could put an end to invasive surgeries.

Bel Marra Health, who offers high-quality, specially formulated vitamins and nutritional supplements, has reported on new research that has shown the success of the first ever biological pacemaker that could put an end to invasive surgeries.

As Bel Marra Health reports in its article, (http://www.belmarrahealth.com/heart-health/heart-patients-to-live-longer-thanks-to-new-gene-therapy/), the study was conducted by Los Angeles’ Cedars-Sinai Heart Institute and published in Science Translational Medicine in July. For this study, 12 pigs with heart block – a condition where the electrical signal is slowed or disrupted as it moves through the heart – were injected with either the single gene, called TBX18, to reprogram cells, or a fluorescent green protein acting as a placebo.

The patch of peppercorn-sized cells acted as a pacemaker for a two-week period, performing the function of a conventional one. During this same period, cardiologists looked at the average heart rate of the pigs in the morning when they ate and at night when they slept.

They found that the gene therapy was fast-acting, reprogramming enough muscle cells to effectively regulate heart rate within 24 to 48 hours. After eight days of testing, the average heart rate was much higher in the pigs that received the therapy than ones that did not.

This “biological pacemaker,” as it’s been dubbed by researchers, could be useful for certain patients, such as those who develop infections from electronic pacemakers and need to have the devices temporarily removed, or fetuses with life-threatening heart disorders who cannot have an electronic pacemaker implanted.

Spokesperson for Bel Marra Health, Dr. Victor Marchione, says, “Since the early 1960s, pacemakers have been widely available, and they’ve constantly improved, becoming more safe and sophisticated.”

Conventional pacemakers are electronic, implanted into the chest to control an abnormal heartbeat. Electronic pacemakers restore regular function to slowing and arrhythmic hearts by using electricity to stimulate heartbeats. That’s a function usually performed by a cluster of thousands of cardiac cells that tell the heart to pump at a regular rate.

These mechanisms are lifesaving for many people with abnormal or slow heart rhythms. But they require an invasive surgery to be installed. So scientists have been waiting for the day when an implant is no longer needed by patients.

Of course, the applications of this new research are still a long way off. And the benefits of a pacemaker usually outweigh the risks. Still, pig hearts are similar to human hearts in their size and the way they work, so there’s good reason to think that the new findings could translate to humans.

(SOURCE: Y.-F. Hu, et al., Biological pacemaker created by minimally invasive somatic reprogramming in pigs with complete heart block. Science Translational Medicine, 2014; 6 (245): 245ra94 doi: 10.1126/scitranslmed.3008681)

Bel Marra Health is the maker of Heart Rescue a high-quality nutritional supplement to help support and maintain heart health. All ingredients are backed with scientific evidence. Every product is tested for safety, quality and purity at every stage of the manufacturing process.

Furthermore, Bel Marra Health products are produced only in Health Canada approved facilities, going the extra mile to ensure that our health-conscious customers are getting top-quality products. For more information on Bel Marra Health visit http://www.belmarrahealth.com or call 1-866-531-0466.

– Courtesy of PRWeb