Related Experiment Video
Updated: May 31, 2026

Quantitative Determination of De Novo Fatty Acid Synthesis in Brown Adipose Tissue Using Deuterium Oxide
Published on: May 12, 2023
Microsomal triglyceride transfer protein restricts steroid production in Leydig cells by regulating SREBP2
Atrayee Chattopadhyay1, Munichandra Babu Tirumalasetty1, Thomas Palaia1
1Department of Foundations of Medicine, NYU Grossman Long Island School of Medicine, Mineola, NY, USA.
Abstract:
Testicular Leydig cells produce testosterone. Decreases in serum testosterone reduce bone density, muscle mass, and sexual functions, and increase obesity and cardiovascular disease. Microsomal triglyceride transfer protein (MTP) is critical for lipoprotein secretion by the liver and intestine. MTP is expressed in the Leydig cells of human and mouse testes, but its function is unknown. MTP inhibition, knockdown, and gene ablation in mouse Leydig cells significantly increased steroid secretion after stimulation with cyclic AMP. MTP deficiency enhanced the expression of cholesterol metabolism genes, luteinizing hormone receptor, and steroid biosynthesis genes. Furthermore, MTP deficiency enhanced the expression and activity of SREBP2. ATAC sequencing revealed enhanced binding of SREBP2 to the promoters of genes in cholesterol metabolism and steroid biosynthesis pathways. SREBP2 knockdown in MTP-deficient cells significantly attenuated the cholesterol and progesterone biosynthesis pathways. These studies show that MTP regulates cholesterol and sex hormone production by modulating SREBP2 activity.
Related Concept Videos
Regulation of Nuclear Protein Sorting
Smooth Endoplasmic Reticulum
The ER provides optimal conditions for synthesizing steroid hormones and lipids, such as phospholipids and triglycerides. Traditionally, lipid metabolism was considered to be a smooth ER function. However, there is no direct evidence to prove that rough ER is completely excluded from lipid...
Cholesterol: Significance and Regulation
Considering cholesterol and...
Overview of Fatty Acid Metabolism
Fatty acids are catabolized in a process called beta-oxidation, which takes place in the matrix of the mitochondria and converts their fatty acid chains into two-carbon units of acetyl groups. The acetyl...
Transducer Mechanism: Nuclear Receptors
About 48 different soluble family members of nuclear receptors are identified that can be divided into two main classes:
Lipid-Lowering Drugs: Statins and Miscellaneous Agents
