Ju Mei,†,‡,∥ Nelson L. C. Leung,†,‡,∥ Ryan T. K. Kwok,†,‡ Jacky W. Y. Lam,†,‡ and Ben Zhong Tang*,†,‡,§ †HKUST-Shenzhen Research Institute, Hi-Tech Park, Nanshan, Shenzhen 518057, China ‡Department of Chemistry, HKUST Jockey Club Institute for Advanced Study, Institute of Molecular Functional Materials, Division of Biomedical Engineering, State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China Guangdong Innovative Research Team, SCUT-HKUST Joint Research Laboratory, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China

Aggregation-Induced Emission: Together We Shine, United We Soar!

Cannon, Barbara, and Jan Nedergaard. Brown Adipose Tissue: Function and Physiological Significance. Physiol Rev 84: 277–359, 2004; 10.1152/physrev.00015.2003.—The function of brown adipose tissue i...

Brown Adipose Tissue: Function and Physiological Significance

### A. Overview

Extracellular purines (adenosine, ADP, and ATP) and pyrimidines (UDP and UTP) are important signaling molecules that mediate diverse biological effects via cell-surface receptors termed purine receptors. In this review particular emphasis is placed on the discrepancy between the

/pdf/receptors-for-purines-and-pyrimidines-56f78tnpew.pdf

Receptors for Purines and Pyrimidines

The intracellular storage and utilization of lipids are critical to maintain cellular energy homeostasis. During nutrient deprivation, cellular lipids stored as triglycerides in lipid droplets are hydrolysed into fatty acids for energy. A second cellular response to starvation is the induction of autophagy, which delivers intracellular proteins and organelles sequestered in double-membrane vesicles (autophagosomes) to lysosomes for degradation and use as an energy source. Lipolysis and autophagy share similarities in regulation and function but are not known to be interrelated. Here we show a previously unknown function for autophagy in regulating intracellular lipid stores (macrolipophagy). Lipid droplets and autophagic components associated during nutrient deprivation, and inhibition of autophagy in cultured hepatocytes and mouse liver increased triglyceride storage in lipid droplets. This study identifies a critical function for autophagy in lipid metabolism that could have important implications for human diseases with lipid over-accumulation such as those that comprise the metabolic syndrome.

/pdf/autophagy-regulates-lipid-metabolism-578j5d1d3j.pdf

Autophagy regulates lipid metabolism

The neurohypophysial peptide oxytocin (OT) and OT-like hormones facilitate reproduction in all vertebrates at several levels. The major site of OT gene expression is the magnocellular neurons of the hypothalamic paraventricular and supraoptic nuclei. In response to a variety of stimuli such as suckling, parturition, or certain kinds of stress, the processed OT peptide is released from the posterior pituitary into the systemic circulation. Such stimuli also lead to an intranuclear release of OT. Moreover, oxytocinergic neurons display widespread projections throughout the central nervous system. However, OT is also synthesized in peripheral tissues, e.g., uterus, placenta, amnion, corpus luteum, testis, and heart. The OT receptor is a typical class I G protein-coupled receptor that is primarily coupled via Gq proteins to phospholipase C-β. The high-affinity receptor state requires both Mg2+ and cholesterol, which probably function as allosteric modulators. The agonist-binding region of the receptor has bee...

The Oxytocin Receptor System: Structure, Function, and Regulation

http://www.weizmann.ac.il/Biological_Regulation/YoramSalomon/YS-1971-2008pdfs/1974-SalLonRod.pdf

A Highly Sensitive Adenylate Cyclase Assay

Cell surface adenosine receptors mediate either stimulation or inhibition of adenylate cyclase activity [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1], and the receptors that mediate these different responses can be discriminated with selected adenosine analogs. 5'-N-Ethylcarboxamide-adenosine is a more potent agonist at stimulatory receptors (Ra) than is N6-phenylisopropyladenosine, whereas the reverse potency order is seen with inhibitory receptors (Ri). The potency of adenosine is intermediate between the potencies of these two analogs. The relative potencies of adenosine receptor agonists are maintained in physiological responses in intact cells, such as steroidogenesis and inhibition of lipolysis. As with adrenergic receptors, subclasses of adenosine receptors differ functionally and pharmacologically.

https://www.pnas.org/content/pnas/77/5/2551.full.pdf

Subclasses of external adenosine receptors

http://www.jbc.org/content/266/17/11341.full.pdf

Perilipin, a major hormonally regulated adipocyte-specific phosphoprotein associated with the periphery of lipid storage droplets.

Perilipin coats the lipid droplets of adipocytes and is thought to have a role in regulating triacylglycerol hydrolysis. To study the role of perilipin in vivo, we have created a perilipin knockout mouse. Perilipin null (peri−/−) and wild-type (peri+/+) mice consume equal amounts of food, but the adipose tissue mass in the null animals is reduced to ≈30% of that in wild-type animals. Isolated adipocytes of perilipin null mice exhibit elevated basal lipolysis because of the loss of the protective function of perilipin. They also exhibit dramatically attenuated stimulated lipolytic activity, indicating that perilipin is required for maximal lipolytic activity. Plasma leptin concentrations in null animals were greater than expected for the reduced adipose mass. The peri−/− animals have a greater lean body mass and increased metabolic rate but they also show an increased tendency to develop glucose intolerance and peripheral insulin resistance. When fed a high-fat diet, the perilipin null animals are resistant to diet-induced obesity but not to glucose intolerance. The data reveal a major role for perilipin in adipose lipid metabolism and suggest perilipin as a potential target for attacking problems associated with obesity.

https://www.pnas.org/content/pnas/98/11/6494.full.pdf

Constantine Londos

Papers

A Highly Sensitive Adenylate Cyclase Assay

Subclasses of external adenosine receptors

Perilipin, a major hormonally regulated adipocyte-specific phosphoprotein associated with the periphery of lipid storage droplets.

Perilipin ablation results in a lean mouse with aberrant adipocyte lipolysis, enhanced leptin production, and resistance to diet-induced obesity

Adipose differentiation-related protein is an ubiquitously expressed lipid storage droplet-associated protein.