Journal News

From the journals: JLR

Clementine Adeyemi
By Clementine Adeyemi
Sept. 7, 2021

An oil check that might be key to brain health. A deletion that reveals more than meets the eye. What cholesterol does between cells. Read about papers on these topics recently published in the Journal of Lipid Research.
 

This oil check might be key to brain health

FTJ-JLR-9-7-21-445x603.jpg
Cristian Newman/Unsplash
One in five Americans over age 65 is predicted to suffer from neurodegenerative
diseases by 2030.

Chances are, you know someone affected by dementia — an umbrella of neurodegenerative conditions encompassing Alzheimer’s, Parkinson’s and other diseases that affect about 50 million people worldwide. Drugs developed to treat these conditions have been largely ineffective. However, a new study in the Journal of Lipid Research by Larry Spears and colleagues at Washington University in St. Louis links a lack of the lipid plasmalogen to the vascular abnormalities associated with these brain diseases.

Plasmalogens are the most common type of phospholipid in the tissues of the nervous system and help protect the brain against oxidative stress, which is known to cause progressive neurodegenerative conditions. Plasmalogens are produced by the endothelial cells that make up the blood–brain barrier, vital for the protection of the brain. Hence, these lipids play two key roles in protecting the brain and keeping it running smoothly.

The authors of this study genetically altered mice so their endothelial cells would have no PexRAP, an enzyme necessary for the synthesis of plasmalogen. Without PexRAP activity, circulating levels of plasmalogens decreased. This resulted in behavioral changes in the mutant mice and structural changes in their brains that are synonymous with neurodegeneration. The behavior changes included decreased physical activity, decreased attention to their environment and impaired spatial memory. Structurally, the number of neuroprotective glial cells increased, signaling a reaction by the nervous system as it sensed damage due to the lack of plasmalogens. In addition, the researchers saw a decrease in tyrosine hydroxylase activity, a consequence of neurodegeneration.

The authors concluded that plasmalogen decreases in the nervous system after vascular damage, leading to impaired brain health. Hence, checking on the levels of the brain’s oil, plasmalogen, could serve as an indicator of brain health.

 

Deletion reveals more than meets the eye

Sphingolipids more commonly are known by their precursor, the popular skincare ingredient ceramides. However, these lipids play a more critical role in a host of physiological processes such as programmed cell death and inflammatory cascades, yet researchers know little about their regulation.

A recent study in the Journal of Lipid Research by Christopher Green and colleagues at Virginia Commonwealth University highlights the complexity of regulating sphingolipid biosynthesis. The researchers investigated the role of the different functional forms of mammalian ORMDL, a protein that negatively regulates the activity of serine palmitoyltransferase complex, or SPT, the enzyme driving sphingolipid biosynthesis. Using a gene-editing tool, the authors developed stable, carcinogenic human lung cells with various functional forms of ORMDL to detect the unique roles of each form.

The results show how these various functional forms of ORMDL uniquely affect sphingolipid metabolism, such as by determining the production of certain sphingolipid groups or by increasing the levels of certain ceramide species over others. These effects have broad implications for the critical body functions, such as cell growth and motility, that require sphingolipids.

 

What cholesterol does between cells

Two hundred years after Robert Hooke discovered cells, scientists got curious about the invisible barriers surrounding animal cells. Almost 50 years later, researchers described the dual nature of the fluid mosaic model of the cell membrane as both hydrophobic and hydrophilic due to its lipid and protein components. Chief among the lipids is cholesterol.

Cholesterol allows for a firm yet permeable cell membrane and is involved in steroid production. Now, a new study in the Journal of Lipid Research by Pawanthi Buwaneka and colleagues at the University of Illinois at Chicago has uncovered additional roles in cell signaling for cholesterol, specifically in the inner layer of the double-layered membrane.

Based on their previous work spotlighting interactions between cholesterol in this layer and intracellular proteins, the researchers’ recent experiments using various cell types including fibroblasts and Leydig cells illustrate how these interactions precede cellular signaling. Using advanced imaging analysis, the authors show how the level of cholesterol in the inner layer is tightly regulated to control intracellular signaling processes. This new role of cholesterol as a signal propagator could have implications for studying cell physiology.

Clementine Adeyemi
Clementine Adeyemi

Clementine Adeyemi is a Ph.D. biomedical student at the University of Cincinnati. Outside the lab, she is passionate about outreach through organizations such as Empowering Female Minds in Stem to broaden who gets to do science.

Join the ASBMB Today mailing list

Sign up to get updates on articles, interviews and events.

Latest in Science

Science highlights or most popular articles

Finding the right research path
Interview

Finding the right research path

Sept. 16, 2021

Karen Bornfeldt, an associate editor for the Journal of Lipid Research, investigates how diabetes increases cardiovascular disease risk.

From the journals: JBC
Journal News

From the journals: JBC

Sept. 15, 2021

Antibody interactions that change cytotoxicity. An atlas for macrophage activation. Anti–Zika virus natural products. Read about papers on these and other topics.

Noboru Sueoka (1929 – 2021)
Retrospective

Noboru Sueoka (1929 – 2021)

Sept. 13, 2021

Sueoka made widely known contributions to our understanding of DNA replication. Indeed, he coined the term “origin of replication.”

From CRISPR to glowing proteins to optogenetics
Feature

From CRISPR to glowing proteins to optogenetics

Sept. 12, 2021

Three pioneering technologies have forever altered how researchers do their work and promise to revolutionize medicine, from correcting genetic disorders to treating degenerative brain diseases.

Lobsters hold the secret of a long, cancer-free life in their genes
News

Lobsters hold the secret of a long, cancer-free life in their genes

Sept. 11, 2021

More than a mere delicacy, the humble lobster could teach us a lot about healthy aging.

Personal chemistry: Proteomics tackles privacy concerns
Feature

Personal chemistry: Proteomics tackles privacy concerns

Sept. 9, 2021

Sharing raw data is an important norm for the proteomics community. But as clinical studies become more detailed, researchers may need to clamp down to protect patient privacy.