Breaking News
May 3, 2019 - Vaping and Smoking May Signal Greater Motivation to Quit
May 3, 2019 - Dementia looks different in brains of Hispanics
May 3, 2019 - Short-Staffed Nursing Homes See Drop In Medicare Ratings
May 3, 2019 - Study of teens with eating disorders explores how substance users differ from non-substance users
May 3, 2019 - Scientists develop new video game that may help in the study of Alzheimer’s
May 3, 2019 - Arc Bio introduces Galileo Pathogen Solution product line at ASM Clinical Virology Symposium
May 3, 2019 - Cornell University study uncovers relationship between starch digestion gene and gut bacteria
May 3, 2019 - How to Safely Use Glucose Meters and Test Strips for Diabetes
May 3, 2019 - Anti-inflammatory drugs ineffective for prevention of Alzheimer’s disease
May 3, 2019 - Study tracks Pennsylvania’s oil and gas waste-disposal practices
May 3, 2019 - Creating a better radiation diagnostic test for astronauts
May 3, 2019 - Vegans are often deficient in these four nutrients
May 3, 2019 - PPDC announces seed grants to develop medical devices for children
May 3, 2019 - Study maps out the frequency and impact of water polo head injuries
May 3, 2019 - Research on Reddit identifies risks associated with unproven treatments for opioid addiction
May 3, 2019 - Good smells may help ease tobacco cravings
May 3, 2019 - Medical financial hardship found to be very common among people in the United States
May 3, 2019 - Researchers develop multimodal system for personalized post-stroke rehabilitation
May 3, 2019 - Study shows significant mortality benefit with CABG over percutaneous coronary intervention
May 3, 2019 - Will gene-editing of human embryos ever be justifiable?
May 3, 2019 - FDA Approves Dengvaxia (dengue vaccine) for the Prevention of Dengue Disease in Endemic Regions
May 3, 2019 - Why Tonsillitis Keeps Coming Back
May 3, 2019 - Fighting the opioid epidemic with data
May 3, 2019 - Maggot sausages may soon be a reality
May 3, 2019 - Deletion of ATDC gene prevents development of pancreatic cancer in mice
May 2, 2019 - Targeted Therapy Promising for Rare Hematologic Cancer
May 2, 2019 - Alzheimer’s disease is a ‘double-prion disorder,’ study shows
May 2, 2019 - Reservoir bugs: How one bacterial menace makes its home in the human stomach
May 2, 2019 - Clinical, Admin Staff From Cardiology Get Sneak Peek at Epic
May 2, 2019 - Depression increases hospital use and mortality in children
May 2, 2019 - Vicon and NOC support CURE International to create first gait lab in Ethiopia
May 2, 2019 - Researchers use 3D printer to make paper organs
May 2, 2019 - Viral infection in utero associated with behavioral abnormalities in offspring
May 2, 2019 - U.S. Teen Opioid Deaths Soaring
May 2, 2019 - Opioid distribution data should be public
May 2, 2019 - In the Spotlight: “I’m learning every single day”
May 2, 2019 - 2019 Schaefer Scholars Announced
May 2, 2019 - Podcast: KHN’s ‘What The Health?’ Bye-Bye, ACA, And Hello ‘Medicare-For-All’?
May 2, 2019 - Study describes new viral molecular evasion mechanism used by cytomegalovirus
May 2, 2019 - SLU study suggests a more equitable way for Medicare reimbursement
May 2, 2019 - Scientists discover first gene involved in lower urinary tract obstruction
May 2, 2019 - Researchers identify 34 genes associated with increased risk of ovarian cancer
May 2, 2019 - Many low-income infants receive formula in the first few days of life, finds study
May 2, 2019 - Global study finds high success rate for hip and knee replacements
May 2, 2019 - Taking depression seriously: What is it?
May 2, 2019 - With Head Injuries Mounting, Will Cities Put Their Feet Down On E-Scooters?
May 2, 2019 - Scientists develop small fluorophores for tracking metabolites in living cells
May 2, 2019 - Study casts new light into how mothers’ and babies’ genes influence birth weight
May 2, 2019 - Researchers uncover new brain mechanisms regulating body weight
May 2, 2019 - Organ-on-chip systems offered to Asia-Pacific regions by Sydney’s AXT
May 2, 2019 - Adoption of new rules drops readmission penalties against safety net hospitals
May 2, 2019 - Kids and teens who consume zero-calorie sweetened beverages do not save calories
May 2, 2019 - Improved procedure for cancer-related erectile dysfunction
May 2, 2019 - Hormone may improve social behavior in autism
May 2, 2019 - Alzheimer’s disease may be caused by infectious proteins called prions
May 2, 2019 - Even Doctors Can’t Navigate Our ‘Broken Health Care System’
May 2, 2019 - Study looks at the impact on criminal persistence of head injuries
May 2, 2019 - Honey ‘as high in sugars as table sugar’
May 2, 2019 - Innovations to U.S. food system could help consumers in choosing healthy foods
May 2, 2019 - FDA Approves Mavyret (glecaprevir and pibrentasvir) as First Treatment for All Genotypes of Hepatitis C in Pediatric Patients
May 2, 2019 - Women underreport prevalence and intensity of their own snoring
May 2, 2019 - Concussion summit focuses on science behind brain injury
May 2, 2019 - Booker’s Argument For Environmental Justice Stays Within The Lines
May 2, 2019 - Cornell research explains increased metastatic cancer risk in diabetics
May 2, 2019 - Mount Sinai study provides fresh insights into cellular pathways that cause cancer
May 2, 2019 - Researchers to study link between prenatal pesticide exposures and childhood ADHD
May 2, 2019 - CoGEN Congress 2019: Speakers’ overviews
May 2, 2019 - A new strategy for managing diabetic macular edema in people with good vision
May 2, 2019 - Sagent Pharmaceuticals Issues Voluntary Nationwide Recall of Ketorolac Tromethamine Injection, USP, 60mg/2mL (30mg per mL) Due to Lack of Sterility Assurance
May 2, 2019 - Screen time associated with behavioral problems in preschoolers
May 2, 2019 - Hormone reduces social impairment in kids with autism | News Center
May 2, 2019 - Researchers synthesize peroxidase-mimicking nanozyme with low cost and superior catalytic activity
May 2, 2019 - Study results of a potential drug to treat Type 2 diabetes in children announced
May 2, 2019 - Multigene test helps doctors to make effective treatment decisions for breast cancer patients
May 2, 2019 - UNC School of Medicine initiative providing unique care to dementia patients
May 2, 2019 - Nestlé Health Science and VHP join forces to launch innovative COPES program for cancer patients
May 2, 2019 - Study examines how our brain generates consciousness and loses it during anesthesia
May 2, 2019 - Transition Support Program May Aid Young Adults With Type 1 Diabetes
May 2, 2019 - Study shows how neutrophils exacerbate atherosclerosis by inducing smooth muscle-cell death
May 2, 2019 - Research reveals complexity of how we make decisions
Research reveals link between immunity, diabetes

Research reveals link between immunity, diabetes

Credit: CC0 Public Domain

When it comes to diet-induced obesity, your immune system is not always your friend.

Adipose (fatty) tissue is infiltrated by white blood cells that have been linked to the development of inflammation, insulin resistance and type 2 diabetes. How this happens is complicated and under intense investigation by researchers around the world.

Now, from a study in mice fed a high-fat diet, Vanderbilt researchers report that a type of immune cell called the CD8+ T cell is activated in fatty tissue by isolevuglandins (isoLGs), chemical products of fatty acid oxidation.

Part of the body’s immune defense system, CD8+ cells attack bacteria, viruses and unhealthy cells including cancer cells. But in fat they also contribute to inflammation, which is thought to block insulin’s ability to remove glucose from the blood. Insulin “resistance,” in turn, can lead to type 2 diabetes.

“This study is important because it enhances our understanding of the immune system and how it contributes to insulin resistance in the setting of obesity,” said the paper’s first author, Wyatt McDonnell, a graduate student in the Department of Pathology, Microbiology and Immunology at Vanderbilt University School of Medicine.

The findings, reported last week in the journal Diabetes, suggest that drugs could be developed to prevent or reverse insulin resistance by targeting isoLGs or CD8+ cells in fatty tissue, added the paper’s corresponding author, Arion Kennedy, Ph.D., a former Vanderbilt faculty member now at North Carolina State University in Raleigh.

The current study was made possible by Kennedy, co-author Alyssa Hasty, Ph.D., and colleagues who showed in earlier work that CD8+ cells can be isolated from adipose tissue. Hasty is the Cornelius Vanderbilt Chair and professor in the Department of Molecular Physiology and Biophysics.

CD8+ T cells contain unique and highly variable “barcodes” that enable them to recognize their targets. Using sophisticated cell sorting and gene-sequencing technology provided through the Vanderbilt Flow Cytometry Shared Resource and VANTAGE (Vanderbilt Technologies for Advanced Genomics), the researchers sequenced the barcode of each CD8+ cell isolated from fat.

This part of the research and the computational analysis was led by McDonnell, who worked with co-author and VANTAGE Scientific Director Simon Mallal, MBBS, the Major E.B. Stahlman Professor of Infectious Diseases and Inflammation.

The researchers found that the barcode changed under conditions of diet-induced obesity. “This led us to discover that isoLGs—a type of modified protein made by cells experiencing stress and injury from oxygen free radicals—are elevated in the fat,” McDonnell said, and that CD8+ cells are activated by them.

“This study is the first to show that the accumulation of CD8+ cells in fat during obesity is not a random process,” said co-author John Koethe, MD, MSCI, assistant professor of Medicine at Vanderbilt.

Koethe said the findings are relevant for patients with HIV disease who also have elevated levels of CD8+ cells in fat and are at high risk of developing diabetes. Last year he received a five-year, $3.6 million grant from the National Institutes of Health (NIH) to better understand and find a solution to this problem.

Studies conducted by co-author Annet Kirabo, Ph.D., MSc, assistant professor in the Division of Clinical Pharmacology, and colleagues also have linked IsoLGs to the development of high blood pressure and vascular disease.

This suggests a conserved pathway by which the immune system “misbehaves” in hypertension, diabetes and obesity. “It also means we could potentially intervene in these settings by quieting down the immune system or by lowering the oxidative stress on cells in the fat,” McDonnell said.


Explore further:
Gamma-Delta T cells may play a role in insulin resistance and type 2 diabetes

More information:
Wyatt J. McDonnell et al. High CD8 T Cell Receptor Clonality and Altered CDR3 Properties are Associated with Elevated Isolevuglandins in Adipose Tissue During Diet-Induced Obesity, Diabetes (2018). DOI: 10.2337/db18-0040

Journal reference:
Diabetes

Provided by:
Vanderbilt University

Tagged with:

About author

Related Articles