Research reveals why our cells make more cholesterol and fat after a big meal

September 12, 2017

While cholesterol and fat are well known dietary risk factors, they are actually produced by every cell in the body and are essential for growth and metabolism. New research led by Dr. Xiaohui Zha reveals how two proteins called mTORC1 and SREBP-2 control this process together. SREBP-2 senses fat and cholesterol in the cell and turns on their production when they are low. mTORC1, on the other hand, boosts their production when it senses that the cell has a lot of energy, like after a big meal. Dr. Zha discovered that mTORC1 does this by hiding fat and cholesterol from the SREBP-2 sensor, thereby “tricking” the cell into making cholesterol and fat unnecessarily. This study, published in PNAS, could lead to new treatments for people with obesity and diabetes, for example by targeting an overactive mTORC1 to prevent excess production of fat and cholesterol.

Authors: Walaa Eid, Kristin Dauner, Kevin C. Courtney, AnneMarie Gagnon, Robin J. Parks, Alexander Sorisky, and Xiaohui Zha

Funders: This study was supported by the Canadian Institutes of Health Research. Research at The Ottawa Hospital is also supported by generous donations from the community.

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