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
New studies on fat cell filling, history of biochemistry, and ketogenic diet

New studies on fat cell filling, history of biochemistry, and ketogenic diet

Brown tissue whitening causes cell death, inflammation

There’s more than one type of fat cell. Besides the white fat that stores triglycerides in lipid droplets in preparation for lean times later, mammals also have heat-generating brown fat, which acts more like a radiator than a storage closet. Brown fat cells are smaller, with more abundant mitochondria than white fat cells, and they hold a lot fewer lipids. In many models of obesity, brown adipose tissue converts to white tissue, with changes in the morphology and function of the cells.

In a recent paper in the Journal of Lipid Research, Petra Kotzbeck, Antonio Giordano and colleagues investigated what happens to brown fat cells after whitening. The researchers, based at the University of Graz, Austria, and the University of Ancona, Italy, found that whitened brown adipocytes enlarged by addition of lipids were more likely to die than white adipocytes of a comparable size. Whitened adipose tissue also had more macrophages, presumably there to clean up the dead cells, and more inflammation under way. The vulnerability of whitened brown adipocytes may explain why gaining fat in the abdomen, where most whitened brown fat is located, is worse for your health than gaining subcutaneous fat.
DOI: 10.1194/jlr.M079665

Syntaxin 17 promotes lipid droplet formation

Cells store energy in lipid droplets, and many such droplets are made in the liver, which plays an important role in coordinating fat metabolism. As new lipid droplets form within the endoplasmic reticulum, acyl coA synthetase 3, or ACSL3, is indispensable for helping them mature. ACSL3 turns free fatty acids into the neutral lipids that fill the lipid droplet.

In a recent article in the Journal of Lipid Research, Hana Kimura and colleagues studying droplet synthesis at Tokyo University of Pharmacy and Life Sciences in Japan report that the binding and scaffolding protein Stx17 is required to move ACSL3 to the nascent lipid droplet at mitochondria-associated membranes within the ER. This new role may explain why Stx17 is abundantly expressed in the liver and adipocytes.
DOI: 10.1194/jlr.M081679

Diet regulates a metabolite, but not in the brain

Ketogenic diets, which reduce carbohydrate intake and prompt the body to rely on fat-derived ketone bodies instead, are a popular treatment for epilepsy and thought to have neuroprotective effects on some other diseases. Mild caloric restriction is also believed to protect neurons. Researchers aren’t sure of the exact molecular mechanism of these diets, but Svenja Heischmann and colleagues at the University of Colorado in Denver have taken a step toward characterizing their effect on the brain.

In a study reported in the Journal of Lipid Research, researchers conducted a metabolomics analysis of both the plasma and brain tissue of mice eating normal or ketogenic chow. They subdivided each diet group into mice eating their fill or eating a restricted amount of chow. The researchers found that, in the bloodstream, kynurenine metabolism changed dramatically. Kynurenine, made from the amino acid tryptophan, can be converted into vitamin B3 or several other metabolites with effects on neurons. However, in the brain, the level of kynurenine changed relatively little.

The research suggests that, while tryptophan degradation is a target of the ketogenic diet, changes in plasma metabolism may not always cross the blood-brain barrier. The researchers intend to explore other metabolic changes in future publications.
DOI: 10.1194/jlr.M079251

Series brings the history of lipid science to light

Since 2013, the Journal of Lipid Research has been running a series of thematic reviews about what organizer Alfred H. Merrill Jr. originally dubbed the “Living History of Lipids.”

In his introduction to the series, Merrill described his motivation for starting the collection this way: “Much of what we know about lipids, and might be inclined to assume was easy to discover, arose from incredibly hard work, cleverly designed experiments, astonishing coincidences, and, sometimes, colossal accidents. This series of thematic reviews is intended to give glimpses into these stories. The authors will try to present the events and personalities as living histories where, when possible, readers will have a sense of stepping back in time.”

Thus far, the series has covered the lipid hypothesis of atherosclerosis, eight decades of bile acid chemistry, the discovery of essential fatty acids, what ApoE knockout and -in mice have taught us about atherogenesis, and early studies of arachidonic acid.

The latest installment, the sixth in the series, by Jean E. Vance of the University of Alberta, was published this spring. It is about the discovery, chemistry and biochemistry of two ubiquitous phosphoglycerolipids — phosphatidylserine and phosphatidylethanolamine.

PS and PE, as they’re known for short, captured Vance’s interest back when she was a postdoctoral researcher at the University of California, San Diego, working in the lab of Daniel Steinberg. (Steinberg, by the way, wrote the first installment of the “Living History” series.).

“My interest in what I felt were the rather neglected phospholipids, PS and PE, arose from some of my preliminary data suggesting that phospholipids could be compartmentalized into distinct pools in cells, perhaps due to specific inter-organelle lipid trafficking events,” Vance recalled. “(M)y research evolved into studying the biosynthesis, cell biology and functions of PS and PE in mammalian cells. Consequently, a major focus of my research was to understand the mechanism by which PS is transported from its site of synthesis in an ER domain — mitochondria-associated membranes, or MAM — to mitochondria for decarboxylation to PE.

Tagged with:

About author

Related Articles