Frank Aaron P, Palmer Biff F, Clegg Deborah J
Biomedical Research Division, Diabetes and Obesity Research Institute, Department of Biomedical Science, Cedars-Sinai Medical Center, Los Angeles, CA, United States.
Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, United States.
Physiol Behav. 2018 Apr 1;187:24-31. doi: 10.1016/j.physbeh.2017.09.026. Epub 2017 Oct 6.
Obesity and its associated co-morbidities are worldwide public health concerns. Obesity is characterized by excessive adipose tissue accumulation; however, it is important to recognize that human and rodent adipose tissues are made up of several distinct adipose tissue sub-types. White adipose tissue (WAT) is considered the prototypical fat cell, due to its capacity and capability to store large amounts of lipid. In contrast, brown adipose tissue (BAT) oxidizes substrates to generate heat. BAT contains more mitochondria than WAT and express uncoupling protein-1 (UCP1), which mediates BAT thermogenesis. A third sub-type of adipose tissue, Brown-in-white (BRITE)/beige adipocytes arise from WAT upon adrenergic stimulation and resembles BAT functionally. The energy burning feature of BAT/beige cells, combined with evidence of an inverse-correlation between BAT/beige adipose tissue and obesity have given rise to the hypothesis that obesity may be linked to BAT/beige 'malfunction'. Females have more BAT and perhaps an enhanced capacity to beige their adipose tissue when compared to males. Multiple signal pathways are capable of activating BAT thermogenesis and beiging of WAT; here, we discuss the potential role of estrogens in enhancing and mediating these factors to enhance adipose tissue thermogenesis.
肥胖及其相关的合并症是全球公共卫生关注的问题。肥胖的特征是脂肪组织过度积累；然而，必须认识到人类和啮齿动物的脂肪组织由几种不同的脂肪组织亚型组成。白色脂肪组织（WAT）因其储存大量脂质的能力而被认为是典型的脂肪细胞。相比之下，棕色脂肪组织（BAT）氧化底物以产生热量。BAT比WAT含有更多的线粒体，并表达解偶联蛋白-1（UCP1），该蛋白介导BAT产热。第三种脂肪组织亚型，即白色脂肪组织中的棕色脂肪细胞（BRITE）/米色脂肪细胞，在肾上腺素能刺激下由WAT产生，在功能上类似于BAT。BAT/米色细胞的能量燃烧特性，以及BAT/米色脂肪组织与肥胖之间负相关的证据，引发了肥胖可能与BAT/米色脂肪组织“功能障碍”有关的假说。与男性相比，女性拥有更多的BAT，并且可能具有更强的将其脂肪组织米色化的能力。多种信号通路能够激活BAT产热和WAT米色化；在此，我们讨论雌激素在增强和介导这些因素以促进脂肪组织产热方面的潜在作用。
