Adipogenesis

Adipogenesis is the process of cell differentiation by which pre-adipocytes become adipocytes (lipocytes, fat cells). Adipogenesis has been one of the most intensively studied models of cellular differentiation. Adipogenesis is the process of cell differentiation by which pre-adipocytes become adipocytes (lipocytes, fat cells). Adipogenesis has been one of the most intensively studied models of cellular differentiation. Adipocytes play a vital role in energy homeostasis and process the largest energy reserve as triglycerol in the body of animals. Adipocytes stay in a dynamic state, they start expanding when the energy intake is higher than the expenditure and undergo mobilization when the energy expenditure exceeds the intake. This process is highly regulated by counter regulatory hormones to which these cells are very sensitive. The hormone insulin promotes expansion whereas the counter hormones epinephrine, glucagon, and ACTH promote mobilization. Adipogenesis is a tightly regulated cellular differentiation process, in which the preadipocytes are transformed into differentiated adipocyte cells. Comparing with cells from other lineage, the in vitro differentiation of fat cells is authentic and recapitulates most of the characteristic feature of in vivo adipogenesis. The key features of differentiated adipocytes are morphological change, growth arrest, high expression of lipogenic genes and production of hormones like leptin, resistin (in the mouse, not in humans) and TNF-alpha. The transition of the fibroblast cells to mature adipocytes is one of the best characterized processes of cellular differentiation. Primary preadipose cells can be isolated from the stromal vascular fraction of adipose tissue; and when treated in cell culture with a combination of adipogenic effectors, they can differentiate into adipocytes. Products of endocrine system such as insulin, IGF-1, cAMP, glucocorticoid,and triiodothyronine effectively induce adipogenesis in preadipocytes.