中医的阳气与线粒体-白色脂肪VS褐色脂肪 Mitochondria, White Adipose Fat Vs Brown Adipose Fat
BAT-brown adipose fat:burn fat
BAT richest in newborns,
BAT distribution
Synthesis of BAT: stimulated by moderate cold exposure, vitamin A, vitamin D and sunshine?
Batokines~cytokines secreted by brown adipose fat
APRIL 28, 2020
People with brown fat may burn 15% more calories
by The Endocrine Society
Short-term cold exposure may help people with brown fat burn 15 percent more calories than those without, according to a small study published in the Endocrine Society's Journal of Clinical Endocrinology & Metabolism.
Unlike white fat, brown fat burns calories through fatty acid oxidation and heat production and is considered a promising target in the fight against the obesity epidemic. The biggest activator of brown fat is moderate cold exposure.
"This data improves our understanding of how brown fat works in humans," said the study's corresponding author, Florian W. Kiefer, M.D., Ph.D., of the Medical University of Vienna in Austria. "We found that individuals with active brown fat burned 20 more kilocalories than those without."
The researchers identified two groups using a PET scan—those with and without active brown fat. They analyzed brown fat function and energy expenditure in these individuals before and after short-term cold exposure finding that the group with active brown fat not only burned significantly more calories but had a healthier fatty acid blood profile.
"We have to study human brown fat in more detail to see if this organ can protect us against metabolic and cardiovascular disease," Kiefer said.People with brown fat may burn 15% more calories
https://medicalxpress.com/news/2020-04-people-brown-fat-calories.html
Vitamin A boosts fat burning in cold conditions
The conversion of white into brown adipose tissue is a promising target for obesity treatment
October 21, 2020
Source: Medical University of Vienna
A recent study conducted by a research team led by Florian Kiefer from MedUni Vienna's Division of Endocrinology and Metabolism shows that cold ambient temperatures increase vitamin A levels in humans and mice. This helps convert "bad" white adipose tissue into "good" brown adipose tissue which stimulates fat burning and heat generation. This "fat transformation" is usually accompanied by enhanced energy consumption and is therefore considered a promising approach for the development of novel obesity therapeutics. The study has now been published in the journal Molecular Metabolism.
In humans and mammals, at least two types of fatty depots can be discerned, white and brown adipose tissue. During obesity development, excess calories are mainly stored in white fat. In contrast, brown fat burns energy and thereby generates heat. More than 90% of the body fat depots in humans are white which are typically located at the abdomen, bottom, and upper thighs. Converting white into brown fat could be a new therapeutic option to combat weight gain and obesity.
A research group led by Florian Kiefer from the Division of Endocrinology and Metabolism, Department of Medicine III at MedUni Vienna demonstrated now that moderate application of cold increases the levels of vitamin A and its blood transporter, retinol-binding protein, in humans and mice. Most of the vitamin A reserves are stored in the liver and cold exposure seems to stimulate the redistribution of vitamin A towards the adipose tissue. The cold-induced increase in vitamin A led to a conversion of white fat into brown fat ("browning"), with a higher rate of fat burning.
When Kiefer and his team blocked the vitamin A transporter "retinol-binding protein" in mice by genetic manipulation, both the cold-mediated rise in vitamin A and the "browning" of the white fat were blunted: "As a consequence, fat oxidation and heat production were perturbed so that the mice were no longer able to protect themselves against the cold," explains Kiefer. In contrast, the addition of vitamin A to human white fat cells led to the expression of brown fat cell characteristics, with increased metabolic activity and energy consumption.
"Our results show that vitamin A plays an important role in the function of adipose tissue and affects global energy metabolism. However, this is not an argument for consuming large amounts of vitamin A supplements if not prescribed, because it is critical that vitamin A is transported to the right cells at the right time," explains the MedUni Vienna researcher. "We have discovered a new mechanism by which vitamin A regulates lipid combustion and heat generation in cold conditions. This could help us to develop new therapeutic interventions that exploit this specific mechanism."
Scientists from Harvard University, Boston and Rutgers University, New Jersey were also involved in the study. The study was funded by the Austrian Science Fund (FWF), the Vienna Science and Technology Fund (WWTF) and the research fund of the Austrian Diabetes Society.Vitamin A boosts fat burning in cold conditions: The conversion of white into brown adipose tissue is a promising target for obesity treatment -- ScienceDaily
https://www.sciencedaily.com/releases/2020/10/201021112318.htm
Myocardin-Related Transcription Factor A Regulates Conversion of Progenitors to Beige Adipocytes
1
Department of Biochemistry, Boston University School of Medicine, Boston, MA 02118, USA
Highlights
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BMP7 induces brown adipogenesis in mesenchymal stem cells
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BMP7 inhibits ROCK and promotes F- to G-actin conversion
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Overexpression of MRTFA or SRF inhibits brown adipogenesis
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Loss of MRTFA promotes browning and resistance to obesity
Summary
Adipose tissue is an essential regulator of metabolic homeostasis. In contrast with white adipose tissue, which stores excess energy in the form of triglycerides, brown adipose tissue is thermogenic, dissipating energy as heat via the unique expression of the mitochondrial uncoupling protein UCP1. A subset of UCP1+ adipocytes develops within white adipose tissue in response to physiological stimuli; however, the developmental origin of these “brite” or “beige” adipocytes is unclear. Here, we report the identification of a BMP7-ROCK signaling axis regulating beige adipocyte formation via control of the G-actin-regulated transcriptional coactivator myocardin-related transcription factor A, MRTFA. White adipose tissue from MRTFA–/– mice contains more multilocular adipocytes and expresses enhanced levels of brown-selective proteins, including UCP1. MRTFA–/– mice also show improved metabolic profiles and protection from diet-induced obesity and insulin resistance. Our study hence unravels a central pathway driving the development of physiologically functional beige adipocytes.心肌相关转录因子A调节祖细胞向米黄色脂肪细胞的转化。
1个
波士顿大学医学院生物化学系，美国马萨诸塞州波士顿02118
强调
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BMP7在间充质干细胞中诱导褐色脂肪形成
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BMP7抑制ROCK并促进F-向G-肌动蛋白转化
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MRTFA或SRF的过表达抑制褐色脂肪形成
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MRTFA的丢失会促进褐变和抵抗肥胖
概要
脂肪组织是代谢稳态的重要调节剂。与以甘油三酸酯形式存储多余能量的白色脂肪组织相反，棕色脂肪组织是热源性的，通过线粒体解偶联蛋白UCP1的独特表达将能量作为热量散发。 UCP1 +脂肪细胞的一个子集在白色脂肪组织内响应生理刺激而发育。然而，这些“ brite”或“ beige”脂肪细胞的发育起源尚不清楚。在这里，我们报告通过控制G肌动蛋白调节转录共激活因子心肌相关转录因子A，MRTFA的调控米色脂肪细胞形成的BMP7-ROCK信号轴的鉴定。来自MRTFA-/-小鼠的白色脂肪组织含有更多的多眼脂肪细胞，并表达增强水平的棕色选择蛋白，包括UCP1。 MRTFA – / –小鼠还显示出改善的代谢特征，并免受饮食诱发的肥胖和胰岛素抵抗。因此，我们的研究揭示了驱动生理功能米色脂肪细胞发展的主要途径。
心肌相关转录因子A调节祖细胞向米黄色脂肪细胞的转化-Myocardin-Related Transcription Factor A Regulates Conversion of Progenitors to Beige Adipocytes - ScienceDirect
https://www.sciencedirect.com/science/article/pii/S009286741401575X
Bone Morphogenetic Protein 7 - an overview | ScienceDirect ...
https://www.sciencedirect.com/topics/biochemistry...
Bone morphogenetic protein (BMP)-7 is an important promoter of osteoblast differentiation that is produced primarily by the kidneys, so that levels are reduced in CKD. This growth factor is necessary for the differentiation of preosteoblasts into mature osteoblasts.
Bone morphogenetic protein 7 (BMP7) belongs to the TGF-β family and is secreted from normal BM stromal cells and several studies have demonstrated its effect on dormancy of cancer cells, including CSCs (Gao et al., 2017). From: Advances in Cancer Research, 2019
Bone Morphogenetic Protein 7 - an overview | ScienceDirect ...
www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/bone-morphogenetic-protein-7
www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/bo