“If there is something wrong,” within the fat tissue, “it affects other places in the body,” said Yigar-Lotem.
Scientists also have long known that excess fat is associated with the risk of health conditions. However, one of the many aspects of obesity that has surprised scientists is that not all fat are the same.
Intestinal fat – fat cells that are close to internal organs in the abdomen – are associated with greater risk of various health problems than the fat under the skin, known as subcutaneous fat. For example, excess intestine fat comes with heart attacks, strokes, diabetes, insulin resistance and increased risk of liver disease. Studies also suggest that intestine fat is more “proinflammatory” than the subcutaneous fat, which can potentially contribute to the poor health associated with obesity.
To better understand what is happening inside the fat tissues, Yigar-Lotm and their colleagues prepared a “cell atlas” of adapocytes as part of the human cell atlas, a global project that is aimed at mapping all cells in the human body.
Researchers created this map using single-mapical RNA sequencing (SNRNA sequence), which measures the molecular cousin of DNA by looking at RNA, which genes are active and to what extent. RNA molecules serve as blueprints for protein, transporting instructions from DNA to its protein-building sites in the cell nucleus. By measuring RNA in the nuclei of cells extracted from fat tissue, the team raised clues about what each cell does inside the tissue.