Stem cells can be stimulated to become fat-burning beige fat cells
The human body has three types of fat cells (adipocytes):
- A large number of the well-known white fat cells, which store fat and are responsible for obesity and cellulite and can contribute to type 2 diabetes
- A much smaller number of the recently discovered and less known brown fat cells, which actually burn fat, instead of storing it, and can help fight type 2 and diabetes
- An also small number of the very recently discovered and much less known beige fat cells, which are white fat cells that behave like brown fat cells
Contrary to the urban myth that we have a set number of fat cells throughout our lifetime, we constantly "lose" old fat cells and "gain" new fat cells (derived from stem cells), throughout our life.
Increasing the amount of fat-burning brown (or at least beige) adipocytes, at the expense of white adipocytes, is the holy grail of weight loss scientists. Until recently, brown and beige fat cells have been seen mainly in mice, but a new paper published this month has shown that human beige adipocytes can actually be derived from human stem cells taken from human adipose (fat) tissue.
The holy grail of fat loss - and cellulite
This is another significant step in the fight against obesity, as the researchers have managed to "instruct" stem cells to become beige fat cells by providing them with special growth factors. These beige fat cells are fully functional and do produce heat by actually burning fat!
The protein UCP1, the hallmark of heat production by fat, was also present in those cells. Furthermore, those cells readily produce heat after stimulation by noradrenaline, another typical brown/beige fat cell function.
In the next few years we expect this exciting field of biology to bear fruits with the discovery of drugs or natural substances that can significantly stimulate the conversion of white fat cells into beige adipocytes, which can help in the fight against obesity, diabetes type II and cellulite.
Already certain herbal extracts exist that do stimulate UCP1, but are either too stimulating for the nervous system (e.g. ephedrine) or not quite effective enough (e.g. fucoxanthin). The hope is that derivatives of those substances can be developed, or new substances can be found, that are much more effective and that can be used either orally (as a supplement) or locally (as an anti-cellulite cream ingredient).
- Paper: Thermogenic Activity of UCP1 in Human White Fat-Derived Beige Adipocytes.
- Abstract: "Heat-producing beige/brite (brown-in-white) adipocytes in white adipose tissue have the potential to suppress metabolic disease in mice and hold great promise for the treatment of obesity and type 2 diabetes in humans. Here, we demonstrate that human adipose-derived stromal/progenitor cells (hASCs) from sc white adipose tissue can be efficiently converted into beige adipocytes. Upon pharmacological activation of PPARγ, hASC-derived adipocytes activated beige fat-selective genes and a brown/beige fat-selective electron transport chain gene program. Importantly, hASC-derived beige fat cells displayed the bioenergetic characteristics of genuine brown fat cells, including a capacity for increased respiratory uncoupling in response to β-adrenergic agonists. Furthermore, knock-down experiments reveal that the thermogenic capacity of human beige fat cells was entirely dependent on the presence of uncoupling protein 1. In summary, this study reveals that hASCs can be readily differentiated into beige adipocytes that, upon activation, undergo uncoupling protein 1-dependent thermogenesis."