Clinical Nutrition Research Centre (CNRC), Singapore Institute for Clinical Sciences (SICS), Agency for Science, Technology and Research (A*STAR) and National University Health System, Singapore.
Department of Nuclear Medicine, First Hospital of Shanxi Medical University, China; Molecular Imaging Precision Medicine Collaborative Innovation Center, Shanxi Medical University, China.
Diabetes Metab. 2017 Oct;43(5):401-410. doi: 10.1016/j.diabet.2017.03.008. Epub 2017 Apr 25.
Body weight gain results from a chronic excess of energy intake over energy expenditure. Accentuating endogenous energy expenditure has been accorded considerable attention ever since the presence of brown adipose tissue (BAT) in adult humans was recognized, given that BAT is known to increase energy expenditure via thermogenesis. Besides classic BAT, significant strides in our understanding of inducible brown adipocytes have been made regarding its development and function. While it is ideal to study BAT histologically, its relatively inaccessible anatomical locations and the inherent risks associated with biopsy preclude invasive techniques to evaluate BAT on a routine basis. Thus, there has been a surge in interest to employ non-invasive methods to examine BAT. The gold standard of non-invasive detection of BAT activation is F-fluorodeoxyglucose positron emission tomography (PET) with computed tomography (CT). However, a major limitation of PET/CT as a tool for human BAT studies is the clinically significant doses of ionizing radiation. More recently, several other imaging methods, including single-photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), infrared thermography (IRT)/thermal imaging and contrast ultrasonography (US) have been developed in hopes that they would allow non-invasive, quantitative measures of BAT mass and activity with lower costs. This review focuses on such methods to detect human BAT activation and white adipose tissue (WAT) browning to prompt the establishment of BAT-centric strategies for augmenting energy expenditure and combatting obesity. Clinical validation of these methods will most likely expand the scope and flexibility of future BAT studies.
体重增加是由于能量摄入长期超过能量消耗所致。自从在成年人体内发现棕色脂肪组织（BAT）以来，人们一直非常关注内源性能量消耗的增加，因为已知 BAT 通过产热来增加能量消耗。除了经典的 BAT，人们对诱导性棕色脂肪细胞的发育和功能的理解也取得了重大进展。虽然从组织学上研究 BAT 是理想的，但由于其相对难以接近的解剖位置以及与活检相关的固有风险，限制了侵入性技术来常规评估 BAT。因此，人们对采用非侵入性方法来检查 BAT 产生了浓厚的兴趣。非侵入性检测 BAT 激活的金标准是 F-氟脱氧葡萄糖正电子发射断层扫描（PET）与计算机断层扫描（CT）相结合。然而，PET/CT 作为人类 BAT 研究工具的一个主要局限性是电离辐射的临床显著剂量。最近，还开发了其他几种成像方法，包括单光子发射计算机断层扫描（SPECT）、磁共振成像（MRI）、红外热成像（IRT）/热成像和对比超声（US），希望它们能够允许非侵入性、定量测量 BAT 质量和活性，同时降低成本。本综述重点介绍了这些检测人类 BAT 激活和白色脂肪组织（WAT）褐变的方法，以促使建立以 BAT 为中心的策略来增加能量消耗和对抗肥胖。这些方法的临床验证极有可能扩大未来 BAT 研究的范围和灵活性。
