Not All Fat Is Equal

It has been unclear why fat cells, which appear so similar, are associated with such different health outcomes," says author Professor Katherine Samaras, Head of the Clinical Obesity, Nutrition and Adipose Biology lab at Garvan and endocrinologist at St Vincent's Hospital Sydney. "Now we start to understand that the different fat cells are wired differently right from the start." In their study, the researchers isolated the fat-storing cells from visceral and subcutaneous fat biopsies from three individuals. The team compared the fat cells' epigenomes, the chemical tags attached to DNA that control how genes are read, and their transcriptomes, the genetic output of the cell. By creating a comprehensive genomic map, the researchers discovered a number of fundamental epigenetic differences linked to changed genetic output, between the cells in subcutaneous and visceral fat. Further, the team discovered these differences arise early in cell development, and are likely present in the precursor cells from which fat cells arise. This finding indicates that despite the fat cells' similar appearance, fat cells become 'hard-wired' early to be harmful or non-harmful. "When compared with other cell types in the body, visceral and subcutaneous fat cells are very similar to each other in their function," says lead author Dr Stephen Bradford. "Our analysis revealed epigenetic differences that may control different genes being turned on in subcutaneous and visceral fat cells that could contribute to their different properties and health effects." "This comprehensive study demonstrated that the epigenome can provide an unprecedented view into the differences of cells that seem apparently very similar," says co-senior author Dr Peter Molloy from the CSIRO. "We believe that such analyses will provide us with further crucial insight not only into the development of fat, but also for other cell types in future." Reference: Bradford et al. 2019. Methylome and transcriptome maps of human visceral and subcutaneous adipocytes reveal key epigenetic differences at developmental genes. Scientific Reports. DOI: https://doi.org/10.1038/s41598-019-45777-w. https://www.technologynetworks.com/genomics/news/not-all-fat-is-equal-321549?utm_campaign=NEWSLETTER_TN_Breaking%20Science%20News&utm_source=hs_email&utm_medium=email&utm_content=74454458&_hsenc=p2ANqtz-9wgcbWW_DCqgsrPqEihxn3tJwEkDgTleyrSYNYdhn9ZvtB4NG3VmeViOx5YeRDfQ32n8POTnIGDAInYR7ZNmhrIp2dbg&_hsmi=74454458