Study identifies enzyme that protects cells from toxic fat

August 1, 2017, Harvard T.H. Chan School of Public Health

A new study from Harvard T.H. Chan School of Public Health and Howard Hughes Medical Institute sheds light on how a key fat-producing enzyme helps protect cells from a toxic form of fat.

The new finding contributes to a fuller understanding of the fundamental biology that underlies common metabolic diseases related to obesity, such as type 2 diabetes, , and heart failure, and could lead to new insights on how to better treat such diseases.

The study will be published online August 1, 2017 in Cell Metabolism.

"We are excited about these findings—they solve a mystery and show how fat synthesis protects cells from dysfunction and ," said Robert Farese, Jr., professor of genetics and complex diseases at Harvard Chan School.

Lead author of the study was Harvard Chan research fellow Chandramohan Chitraju.

The researchers looked at what happens to (a type of fat) in cells during lipolysis, the through which the triglycerides are broken down into and transported for energy use to other tissues in the body. For decades, scientists have wondered why some triglycerides, after being broken down into fatty acids, wind up back in the cells in the form of triglycerides—a process known as "re-esterification."

By examining cell processes both in mice and in human cells, the researchers found out why: Re-esterification helps protect a key cell organelle called the endoplasmic reticulum (ER). The ER helps make cellular products such as proteins and lipids and it can be damaged by fatty acids—but not by triglycerides. The researchers also found that an enzyme called DGAT1 (diacylglycerol acyltransferase) is crucial to the re-esterification process, acting as a sort of cell police officer to ensure that toxic fatty acids stay away from the ER.

"To better understand what happens when are overwhelmed with fat during obesity, we first have to understand how the system normally deals with fluctuations in lipids," said Tobias Walther, professor of genetics and complex diseases at Harvard Chan and co-senior author of the study. "Our findings will hopefully spark new ideas on how to prevent the health consequences of obesity."

Explore further: Researchers make a case for free fatty acids

More information: "Triglyceride Synthesis by DGAT1 Protects Adipocytes from Lipid-Induced ER Stress during Lipolysis," Cell Metabolism (2017). DOI: 10.1016/j.cmet.2017.07.012

Related Stories

Researchers make a case for free fatty acids

October 22, 2013

The current global epidemic of obesity-linked diabetes and its associated consequences -cardiovascular, neurological and renal diseases - is a growing public health problem for which therapeutic options are limited.

Saturated fatty acids might directly damage heart

April 27, 2015

Olive oil is universally considered a much healthier alternative to meat fat. Plant-derived oils (such as olive oil, canola oil, and vegetable oil) largely consist of unsaturated fatty acids, whereas animal fat is richer ...

Unveiling the nasty action of trans-fatty acids in blood

May 18, 2017

Tohoku University researchers have found that trans-fatty acids promote cell death in a more direct manner than previously thought, leading to the development of atherosclerosis, a major cause of heart attacks and strokes.

The biology of fats in the body

April 29, 2013

When you have your cholesterol checked, the doctor typically gives you levels of three fats found in the blood: LDL, HDL and triglycerides. But did you know your body contains thousands of other types of fats, or lipids?

New way of visualizing fatty acids inside cells

February 3, 2017

International researchers, including those from Osaka University, developed a new method to image intracellular fatty acids at a single cell level. They treated cells with fatty acids containing a single bromine atom and ...

Recommended for you

Nanoscale Lamb wave-driven motors in nonliquid environments

March 19, 2019

Light driven movement is challenging in nonliquid environments as micro-sized objects can experience strong dry adhesion to contact surfaces and resist movement. In a recent study, Jinsheng Lu and co-workers at the College ...

OSIRIS-REx reveals asteroid Bennu has big surprises

March 19, 2019

A NASA spacecraft that will return a sample of a near-Earth asteroid named Bennu to Earth in 2023 made the first-ever close-up observations of particle plumes erupting from an asteroid's surface. Bennu also revealed itself ...

The powerful meteor that no one saw (except satellites)

March 19, 2019

At precisely 11:48 am on December 18, 2018, a large space rock heading straight for Earth at a speed of 19 miles per second exploded into a vast ball of fire as it entered the atmosphere, 15.9 miles above the Bering Sea.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.