The researchers report evidence in people and mice, linking low adiponectin levels to insulin resistance and reductions in the number of "cellular power plants" called mitochondria in skeletal muscle. The findings suggest that therapies designed to boost the adiponectin signal might prove beneficial for the treatment of insulin resistance and diabetes, they said.
"We have discovered a skeletal muscle pathway by which adiponectin increases mitochondrial number and function and exerts antidiabetic effects," said lead author Anthony Civitarese from Pennington Biomedical Research Center in Baton Rouge, Louisiana.
Mitochondria utilize nutrient components, including fats and carbohydrates, to generate usable energy. The number of mitochondria therefore influences the way that muscles function. For example, people who exercise regularly have more mitochondria in their muscles than do those who are sedentary.
Earlier studies found that obese individuals and those with type 2 diabetes have reduced adiponectin concentrations, the researchers said. The new study examined the effects of that reduced adiponectin on skeletal muscle.
The researchers first examined children whose parents had type 2 diabetes and those with no family history of the disease. Muscle taken from individuals prone to diabetes was insulin resistant and had lower than normal concentrations of mitochondrial enzymes, suggesting some dysfunction, they found. The level of adiponectin also correlated with the estimated number of mitochondria in the muscle samples.
Further study of adiponectin-deficient mice similarly found that the animals were resistant to insulin and exhibited deficits in mitochondria in their skeletal muscles.
Finally, the researchers showed that adiponectin treatment of human muscle tissue in culture sparked the production of mitochondria. The treatment also limited the production of harmful free radicals, or reactive oxygen species, a sign that the mitochondria were operating more efficiently.
The current findings, together with earlier studies that showed that adiponectin increases glucose uptake from the blood stream, suggest that the hormone might have therapeutic potential for those with insulin resistance or type 2 diabetes, Civitarese said.
However, adiponectin itself is difficult to produce in the quantities that would be required for a drug, he added.
"It may be that a mimetic drug that acts like adiponectin might prove beneficial," he said.
Heidi Hardman | EurekAlert!
During HIV infection, antibody can block B cells from fighting pathogens
14.08.2018 | NIH/National Institute of Allergy and Infectious Diseases
First study on physical properties of giant cancer cells may inform new treatments
14.08.2018 | Brown University
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur
What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...
The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.
Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...
08.08.2018 | Event News
27.07.2018 | Event News
25.07.2018 | Event News
14.08.2018 | Information Technology
14.08.2018 | Life Sciences
14.08.2018 | Life Sciences