Navigation Links
Joslin researchers uncover potential role of leptin in diabetes
Date:10/1/2007

BOSTONOctober 1, 2007A new Joslin-led study has shown that leptin, a hormone known mainly for regulating appetite control and energy metabolism, plays a major role in islet cell growth and insulin secretion. This finding opens up new avenues for studying leptin and its role in islet cell biology, which may lead to new treatments for diabetes. This study appears in the October 2007 issue of The Journal of Clinical Investigation.

Previous in vitro studies suggested that leptin receptors, which are found in tissues throughout the body including the pancreas as well as the brain, mediate leptin-induced inhibition of insulin secretion in islet cells, also known as beta cells. We wanted to further our understanding of leptin and its role in beta cells independent of its effects in the brain, said Rohit N. Kulkarni, M.D., Ph.D., principal investigator at Joslin Diabetes Center and Assistant Professor of Medicine at Harvard Medical School, who led this study. It is currently not known why obese individuals exhibit a high incidence of diabetes despite high levels of both insulin and leptin circulating in the bloodstream.

To understand the role of leptin in the islets, researchers developed a mouse model (known as a knock out or KO mouse) genetically engineered not to produce leptin receptors in the pancreas, while maintaining the receptors in the brain and the rest of the body. Researchers found that the mice lacking leptin receptors in the pancreas showed improved glucose tolerance and greater insulin secretion and beta cell growth. Since the normal function of leptin is to keep insulin levels from getting too high, the lack of leptin enhances insulin action in the beta cells and promotes insulin secretion, which was the result we expected, said Dr. Kulkarni.

In the second part of the study, the KO mice and a control group of mice with intact leptin receptors were placed on a high-fat diet. Although both the control and KO mice became obese, only the KO mice developed severe glucose intolerance and insulin resistance, a precursor to the development of diabetes. These novel results indicate that in the presence of obesity, the combination of insulin resistance in the beta cell and the lack of leptin signaling leads to poor beta cell growth and function leading to glucose intolerance. Interactions between leptin and insulin signaling in the beta cell need to be considered to understand the relationship between diabetes and obesity, said Dr. Kulkarni.

Obesity is a major risk factor for the development of type 2 diabetes, the most common form of the disease. Other risk factors are age (over 40) and a family history of diabetes, although today it is increasing prevalent in younger people, including adolescents. In type 2 diabetes, islet cells malfunction and the body is unable to compensate by growing more beta cells. By investigating the cellular mechanisms that affect islet cell development and growth, Joslin researchers hope to find better ways to prevent and treat the disease.

Follow-up studies will focus on examining the interactions between insulin and leptin signaling in beta cells and identifying the key proteins found in the pathways that regulate beta cell growth and activity. This could lead to the development of therapeutic drugs that manipulate these proteins to influence beta cell growth and function. Unraveling the role of leptin in the regulation of beta cell biology will be especially useful in understanding the mechanisms that contribute to beta cell growth with implications for the treatment of both type 1 and type 2 diabetes, said Dr. Kulkarni.


'/>"/>

Contact: Jenny Eriksen
jenny.eriksen@joslin.harvard.edu
617-732-2415
Joslin Diabetes Center
Source:Eurekalert

Related biology news :

1. Big hips, big belly? Its in your genes, Joslin-led study shows
2. Joslin discovers signs of residual islet cell function in people with long-term type 1 diabetes
3. Researchers discover way to make cells in the eye sensitive to light
4. Researchers find how protein allows insects to detect and respond to pheromones
5. Researchers Uncover Key Step In Manufacture of Memory Protein
6. NYU researchers simulate molecular biological clock
7. Researchers reveal the infectious impact of salmon farms on wild salmon
8. Researchers identify target for cancer drugs
9. Vital step in cellular migration described by UCSD medical researchers
10. ASU researchers finds novel chemistry at work to provide parrots vibrant red colors
11. UCSD researchers maintain stem cells without contaminated animal feeder layers
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:8/12/2020)... ... August 11, 2020 , ... Both Roche, based in Basel, ... license agreements with Housey Pharma’s HMI subsidiary to gain access to its core-enabling ... Research and Development spending in excess of US $10 billion. , Scientists at ...
(Date:8/5/2020)... ... 05, 2020 , ... Regenative Labs has received approval from the Centers for ... them the first Wharton’s jelly allografts to be assigned a Q code and be ... the first Wharton’s jelly allograft product to be recognized as a 361 HCT/P by ...
(Date:7/22/2020)... ... July 21, 2020 , ... USDM Life Sciences , ... announces a new solution to manage regulated workloads on Microsoft Azure. , Regulated ... stack complies with FDA and global regulations. USDM's new managed service for regulated ...
Breaking Biology News(10 mins):
(Date:7/18/2020)... ... July 17, 2020 , ... ... the life sciences and food industries, is pleased to announce that Charles Galea ... – Business Development. , Charles is an accomplished and results-driven sales executive with ...
(Date:7/10/2020)... ... July 09, 2020 , ... PathSensors Inc., ... has expanded the company’s exclusive license to include clinical applications for CANARY™ ... market, focusing initially on the SARS-CoV-2 biosensor. CANARY’s™ fast and highly ...
(Date:7/10/2020)... ... 09, 2020 , ... Sentien Biotechnologies, Inc., a clinical-stage biotechnology ... R. Nissenson, M.D., F.A.C.P., as its Chief Medical Officer. Dr. Nissenson will ... SBI-101. Dr. Nissenson serves as an Emeritus Professor of Medicine at the ...
(Date:7/7/2020)... ... July 06, 2020 , ... Bio-IT World has announced the ... Squibb, the University of Chicago, Massachusetts General Hospital, Mission: Cure, and the Pistoia ... program, highlighting outstanding examples of how technology innovations and strategic initiatives can be ...
Breaking Biology Technology: