Lipid Transport in Brown Adipocyte Thermogenesis

Abstract

Non-shivering thermogenesis is an energy demanding process that primarily occurs in brown and beige adipose tissue. Beyond regulating body temperature, these thermogenic adipocytes regulate systemic glucose and lipid homeostasis. Historically, research on thermogenic adipocytes has focused on glycolytic metabolism due to the discovery of active brown adipose tissue in adult humans through glucose uptake imaging. The importance of lipids in non-shivering thermogenesis has more recently been appreciated. Uptake of circulating lipids into thermogenic adipocytes is necessary for body temperature regulation and whole-body lipid homeostasis. A wide array of circulating lipids contribute to thermogenic potential including free fatty acids, triglycerides, and acylcarnitines. This review will summarize the mechanisms and regulation of lipid uptake into brown adipose tissue including protein-mediated uptake, lipoprotein lipase activity, endocytosis, vesicle packaging, and lipid chaperones. We will also address existing gaps in knowledge for cold induced lipid uptake into thermogenic adipose tissue.

Molecular and Physiological Effects of Browning Agents on White Adipocytes from Bone Marrow Mesenchymal Stromal Cells

“…To gain more insight into these processes, we grew white adipocytes in media supplemented with a single nutrient (fatty acid or glucose) and then evaluated mitochondrial oxygen consumption, since it is well-known that thermogenic adipocytes (brown and beige cells) manage lipid and glucose homeostasis in order to modulate body temperature. Heat production, or thermogenesis, is a powerful energetic mechanism, and brown adipocytes need a fast and accessible power source, represented principally by glucose and/or free fatty acids [ 33 , 34 ]. Our results were consistent with the findings reported in the literature: in the presence of glucose, we observed an increase in mitochondrial oxygen consumption, primarily after treatment with GW, SID, and IRI ( Figure 4 B).…”

Okra (Abelmoschus esculentus L. Moench) prevents obesity by reducing lipid accumulation and increasing white adipose browning in high-fat diet-fed mice

“…42,43 The lipolysis of TG to liberate FFAs and glycerol is necessary for WAT browning, and the released FFAs can be oxidized in mitochondria to generate heat. 44 Complete lipolysis requires a series of lipases and is regulated by PKA. 45 In the present study, we found that OKC induces the phosphorylation of PKA and increases the expression of the lipolytic enzymes ATGL, p-HSL, and MGL, which results in less TG storage in WAT.…”

Antibodies Regulate Dual-Function Enzyme IYD to Induce Functional Synergy between Metabolism and Thermogenesis

“…These thermogenic adipocytes are considered to have unique developmental origins, bioenergetics, and physiological functions. Thermogenic adipocytes use lipid and glucose to regulate body temperature [ 21 , 22 ]. Consistent with previous studies, our results support that H3 Ab induces stem cells to differentiate into brown adipocyte-like cells, and these cells contribute to increased production of heat energy and core body temperature via non-shivering thermogenesis at room temperature.…”