Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UCLA scientists discover hormone may spur dramatic weight loss

23.07.2002

The only known adults in the world who possess a rare genetic mutation that prevents their bodies from producing leptin may open the door to a new way of fighting fat. After injections with leptin -- a human hormone linked to appetite control -- the adults’ dramatic weight loss suggests that leptin offers significant promise for treating obesity.

Dr. Julio Licinio, professor of medicine at the David Geffen School of Medicine at UCLA, flew three cousins -- two women and one man -- from a tiny village in Turkey to UCLA Medical Center last September for clinical research treatment with leptin. Ranging in age from the late 20s to 40, all of the cousins were severely obese and one was still prepubescent.

"We hypothesized that leptin deficiency may lead to obesity and, in some cases, delay sexual and psychological maturity," explained Licinio, also a professor of psychiatry and biobehavioral sciences at the UCLA Neuropsychiatric Institute. "Although this is a small study, it produced striking results."

Ten months after the study began, the three adults have lost half of their body weight -- more than 150 pounds each. But the leptin therapy resulted in dramatic outcomes beyond their weight loss, including physiological and personality changes.

After receiving leptin injections, the prepubescent adult began experiencing a wide range of physiological changes associated with adolescence and rapidly reached sexual maturity. In addition, UCLA researchers observed neurological growth in all three participants.

"At the end of the study, we measured the subjects’ brains with MRI and discovered that the organs had expanded a small but significant amount," Licinio said. "While the relevance of this outcome is currently unclear, it poses the first known instance of brain growth in adults."

Earlier research conducted on laboratory animals born without the ability to make leptin showed that they possessed brains 30 percent smaller than their normal counterparts. Until now, however, scientists had never studied the effect of leptin deficiency and replacement in humans.

The cousins’ dispositions also altered. Within two weeks of leptin therapy, they grew noticeably more assertive and independent.

"The subjects’ personality changes suggest that there is a relationship between fat and how we feel," Licinio said. "We plan to explore leptin’s link to mood disorders in the future."

Manufactured in the fat cells, leptin plays three important roles in the human body. First, the hormone signals fullness, controls the appetite and tells the brain to stop eating. Second, it is triggered by puberty and regulates sexual development. And third, it helps the immune system fight off diseases -- a critical weapon in staving off childhood diseases.

According to Licinio, science originally considered leptin a gold mine for weight control. Later, however, researchers discovered that obese people produced too much of the hormone and their bodies simply stopped responding to its appetite cues.

In rare cases, though, some people -- like the adults in Licinio’s study -- become obese because they manufacture too little leptin. Licinio decided to study the cousins in order to better understand the role that leptin plays in normal human biology.

The only side effect of the leptin replacement therapy was a minor rash at the injection site that lasted briefly in one patient.

Licinio is a member of the Brain Research Institute, director of the UCLA Pharmacogenetics and Pharmacogenomics Research Group, and founding editor-in-chief for The Pharmacogenomics Journal and Molecular Psychiatry.

The UCLA study was funded by the National Institute of Diabetes, Digestive and Kidney Diseases and the National Center for Research Resources. Licinio’s colleagues at the UCLA Neuropsychiatric Institute included Dr. Ma-Li Wong, Dr. Edythe London, Dr. Sinan Caglayan, and Dr. Bulent Yildez. Licinio also collaborated with Dr. Metin Ozata at the Gulhane School of Medicine in Turkey.

The Thousand Oaks-based pharmaceutical firm Amgen supplied the UCLA researchers with complimentary leptin for the duration of the study and paid $7,500 to Licinio for patient recruitment.

Future UCLA projects will explore the interactions of leptin and other hormones in the elderly, how leptin replacement influences the human endocrine system, and the effect of a single mutation in one of the two genes that encode for human leptin.

Elaine Schmidt | EurekAlert

More articles from Health and Medicine:

nachricht A whole-body approach to understanding chemosensory cells
13.12.2017 | Tokyo Institute of Technology

nachricht Research reveals how diabetes in pregnancy affects baby's heart
13.12.2017 | University of California - Los Angeles Health Sciences

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

A whole-body approach to understanding chemosensory cells

13.12.2017 | Health and Medicine

Water without windows: Capturing water vapor inside an electron microscope

13.12.2017 | Physics and Astronomy

Cellular Self-Digestion Process Triggers Autoimmune Disease

13.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>