Weight loss has become an eternal topic, both men and women are eager to get rid of the body fat. Obesity not only makes you say goodbye to beauty and self-confidence and turn into a melancholy fat, but also invites diabetes, high blood pressure, high blood pressure and other rich diseases. But fat is not always our enemy, it also has good and bad.
”Good fat” and “bad fat”
Early studies found that there are two types of fat in the human body, which are divided into white fat (White Adipose) and brown fat (Brown Adipose) according to their color, structure, function and other differences.
White fat can be regarded as a store of energy, the cell form is single-room structure, large volume of single-room structure helps to store excess energy in the form of triglycerides, once too much energy accumulation and too little consumption, white fat will be a lot of accumulation, especially in the thighs, waist, buttocks fat accumulation is particularly obvious, thus causing obesity.
Brown fat cells are multi-room structure, which contains a large number of mitochondria and capillary network, so the fat appears brown. In addition, the mitochondria of brown adipocytes contain an uncoupling protein (UCP1), which facilitates the conversion of energy from glucose and fatty acids into heat.
In newborns, brown fat is mainly located at the scapula and helps maintain body temperature. As the body ages, brown fat decreases. Eventually, only a small number of brown fat cells remain in the body, located in the neck, whose main function is to absorb energy and release it as heat, thus regulating the body’s energy balance and preventing obesity. Therefore, brown fat is rightly regarded as “good fat”, while white fat is regarded as “bad fat”.
The third type of fat
In recent years, careful scientists have discovered that in cold environments, in addition to increased thermogenesis of brown fat tissue in the body, enhanced thermogenic activity and expression of UCP-1 also occur in subcutaneous white fat, which led to the discovery of a third type of fat in addition to white fat and brown fat – Beige Adipose.
Beige adipose coexists with white adipose in the human body, and its thermogenic gene UCP-1 has a strong induction capacity similar to that of brown adipose, but is differentiated from white adipose precursor cells, so scientists regard beige adipose as a product of browning of white adipose.
The structure of beige adipocytes is between brown adipocytes and white adipocytes, with a multi-compartmental structure, containing a large number of small oil droplets and a higher number of mitochondria than white adipocytes but lower than brown adipocytes. Beige fat has many advantages, if we can artificially regulate the browning of white fat and appropriately transform some tired white fat, it is of great significance for the balance of human energy metabolism. Therefore, beige fat is also rightfully a “good fat”.
Obesity inhibits the production of beige fat
The amount of beige fat in the body of adults varies from person to person, and obese people are the ones who need beige fat to consume excess energy. However, studies have shown that obese people have less beige fat in their bodies than normal people. What exactly is the connection between obesity and the production of beige fat?
For this question, we must first clarify that adipose tissue is an endocrine organ besides storing energy, which can secrete a variety of cytokines and participate in nutrition and immune regulation. The occurrence of obesity is often accompanied by the abnormal secretion of white adipocytes. In obese people, the expression of pro-inflammatory factors is higher than that of anti-inflammatory factors in large white adipocytes, which leads to the accumulation of inflammatory cells in adipose tissue, resulting in a long-term chronic inflammatory response. Therefore, the idea that the occurrence of obesity must be accompanied by a long-term chronic inflammatory response in white adipose tissue has been recognized by a wide range of scholars. This long-term chronic inflammatory environment will inhibit the browning of white fat, thus preventing the formation of beige fat and further reducing its own energy consumption, eventually forming a vicious circle.
Getting the “bad fats” out of the way
After we fully understand the characteristics and differences between “good fats” and “bad fats”, we can make a bold hypothesis: if we convert some of the “bad fats” in our body into “Good fat” can regulate the body’s energy balance, you can have a long-lasting slim body. Scientific research has proven that it is perfectly feasible to convert “bad fats” to good fats. A variety of hormones in living organisms, such as norepinephrine, estrogen, glucocorticoids, can participate in the regulation of white fat browning, but due to the complex mechanism of action of these hormones, it is not easy to control and has a lot of side effects, are not suitable for transformation into weight loss products. However, the discovery of “irisin” has brought a new light to this field.
Bruce Spiegelman, a professor of cell biology at Harvard Medical School, cracked the mechanism of exercise for weight loss and found that exercise can promote muscle expression of peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), and the increase of PGC-1α can induce the release of a muscle called “irisin “irisin, a muscle-activated factor secreted by skeletal muscle, is released into the blood during exercise and acts on white adipocytes to induce white fat browning by stimulating intracellular peroxisome proliferator-activated receptor alpha (PPAR-α).
Animal experiments demonstrated that an appropriate increase of irisin in circulating blood improved obesity and glucose metabolic balance in mice, suggesting that irisin-induced white fat browning facilitates the balance of energy metabolism and has a therapeutic effect on obesity. In addition, the safety of irisin has been initially recognized in animal experiments, and no significant side effects and complications were found in mice with appropriately elevated levels of irisin in circulating blood.
Currently, scientists are studying in depth the mechanism of irisin to promote the browning of white fat, and when the mystery of irisin is completely uncovered in the future, the treatment of obesity is expected to lose weight by injecting or taking irisin orally.
The “good fat” can also be transplanted?
In the future, if you want to lose weight, you can get an injection of irisin. This idea is indeed very attractive, but this kind of fast food injection always makes people bored. According to the researchers’ calculations, brown fat can consume the same amount of energy as white fat in one year. It follows that a very small amount of brown adipose tissue can improve the body’s energy metabolic balance. Thus, some bold scientists came up with the idea of transplanting brown fat.
It was found that brown adipose stem cells extracted from brown adipose tissue could stably form brown fat under the induction of in vitro lipogenic medium, but this idea was difficult to promote due to the small amount of brown fat and the difficulty of obtaining it. Therefore, some scholars began to use the in vitro 3D culture mode of composite biological scaffolds of stem cells extracted from white adipose tissue to construct brown adipose tissue under the induction of material biomechanics or chemical elements of culture medium. When the in vitro constructed brown adipose tissue is implanted into obese mice, tissue resorption will occur in the early stage, and a small amount of tissue will be preserved in the host for a long time after 3 months, and the weight of the host will be gradually reduced and eventually stabilized after transplantation. In addition, there is a significant therapeutic effect on mice with II diabetes and glucose metabolism disorders.
This technology is still in the experimental stage and has a long way to go for clinical application. Firstly, white fat stem cells are not homologous with brown fat stem cells, and the purity of brown fat constructed from white fat stem cells is often not ideal; secondly, the absorption rate of the grafts and their stability after long-term preservation need to be improved.
Whether it is to make “bad fat” from good, or transplant “good fat”, these two technologies are the gospel of the majority of fat people. I believe that with the progress of science and technology, in the near future, the way to lose weight is no longer limited to the gym desperately, starving at the dinner table, beauty hospital liposuction, may be injected Iris or transplant brown fat, open the whole body weight loss mode.