BRCA1 is a gene normally expressed in the cells of breast and other tissue that helps repair damaged DNA or destroy cells if DNA cannot be repaired. BRCA1 mutations increase the risk of breast and ovarian cancers in women. Now a new study from researchers at the University of Maryland School of Public Health as published in the Journal of Lipid Research finds that the gene plays a critical role in the normal metabolic function of skeletal muscle.
Researchers led by Dr. Espen Spangenburg, associate professor of kinesiology, have identified that the BRCA1 protein is expressed in the skeletal muscle of humans. Additionally, the BRCA1 gene plays a key role in fat storage, insulin response, and mitochondrial function in skeletal muscle cells. Because of the normal function of the gene, BRCA1 mutations may increase the risk of metabolic diseases.
Explains Dr. Spangenburg:
“Our findings suggest that certain mutations in the BRCA1 gene may put people at increased risk for metabolic diseases like obesity and type 2 diabetes. Without BRCA1, muscle cells store excess fat and start to look diabetic. We believe that the significance of the BRCA1 gene goes well beyond breast cancer risk.”
The researchers of the present study are the first to find evidence that the BRCA1 protein exists in human skeletal muscle since the discovery of BRCA1 in 1994. The researchers additionally found that the protein produced by the BRCA 1 gene binds with a protein known to play an important role in the metabolism of fat in muscle cells, the Acetyl-CoA carboxylase or ACC. After exercise, the BRCA 1 protein binds to and deactivates ACC, encouraging the utilization of fatty acids by the muscle.
More importantly, mutations in the BRCA1 gene resulted in increased lipid storage, decreased insulin signaling, reduced mitochondrial function, and increased oxidative stress, all of which are risk factors for metabolic diseases such as obesity, type 2 diabetes, and cardiovascular disease.
Concludes Dr. Spangenburg, “Our findings make it clear that BRCA1 plays a protective role against the development of metabolic disease. This gene needs to be there, and should be considered a target to consider in the treatment of type 2 diabetes and/or obesity.”
References
BRCA 1 Breast Cancer Gene Plays a Protective Role Against the Development of Metabolic Disease: http://www.medicalnewstoday.com/releases/273971.php
BRCA1 Is a Novel Regulator of Metabolic Function in Skeletal Muscle: http://www.jlr.org/content/early/2014/02/24/jlr.M043851.abstract
Image Credits
Woman with BRCA1 Breast Cancer Gene: http://www.freeimages.com/photo/1404437
