Multiple symmetric lipomatosis (MSL) is an inherited disorder in which enlarging and unencapsulated lipomas symmetrically develop in the subcutaneous tissue of the neck, shoulders, mammary, and truncal regions. In some cases, it is associated with mitochondrial DNA abnormalities. The pathogenesis of MSL is completely unknown, although the fat deposits may be due to a neoplastic-like proliferation of functionally defective brown adipocytes. It has recently been demonstrated that the beta(3)-adrenergic receptor is the functionally relevant adrenergic receptor subtype in brown adipocytes and that its stimulation by noradrenaline (NA) modulates the expression of genes, such as uncoupling protein (UCP)-1 and inducible nitric oxide synthase (iNOS), involved in fat cell proliferation and differentiation. Furthermore, Trp64Arg mutation of the beta(3)-adrenoceptor has been implicated in lower NA activity in adipose tissues. The aim of this study was to investigate the molecular and functional characteristics of MSL adipocytes and to analyse the effects of nitric oxide (NO) on the proliferation/differentiation of MSL adipocytes in culture, and the relevance of putative noradrenergic deficit in the development of lipomas in MSL patients. Cultured MSL adipocytes were able to synthesize UCP-1 (the selective marker of brown adipocytes), but unlike that of normally functioning brown fat cells, the expression of the UCP-1 gene was not significantly induced by NA. NA is also defective in inducing iNOS gene expression, thus leading to reduced NO production and a consequent reduction in the anti-proliferative, adipogenic (mitochondrial biogenesis) effects of NA on MSL cells. Furthermore, the transcriptional peroxisome proliferator-activated receptor gamma co-activator-1 (PGC-1), which plays a key role in the sympathetic-stimulated mitochondrial biogenesis of brown adipocytes, is expressed but not induced by NA in MSL cells, as it is in brown adipocytes. The study did not find any association between beta(3)-adrenoceptor gene polymorphism and noradrenergic signalling defects in MSL subjects with or without mitochondrial DNA mutations.
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http://dx.doi.org/10.1002/path.1212 | DOI Listing |
Curr Obes Rep
January 2025
Maine Medical Center Research Institute, Maine Medical Center, 81 Research Drive, Scarborough, ME, 04074, USA.
Purpose Of Review: Bone marrow adipose tissue is a distinctive fat depot located within the skeleton, with the potential to influence both local and systemic metabolic processes. Although significant strides have been made in understanding bone marrow adipose tissue over the past decade, many questions remain regarding their precise lineage and functional roles.
Recent Findings: Recent studies have highlighted bone marrow adipose tissue's involvement in continuous cross-talk with other organs and systems, exerting both endocrine and paracrine functions that play a crucial role in metabolic homeostasis, skeletal remodeling, hematopoiesis, and the progression of bone metastases.
Zhejiang Da Xue Xue Bao Yi Xue Ban
January 2025
School of Life Science, Zhejiang Chinese Medical University, Hangzhou 310053, China.
Objectives: To investigate the effect of pachymic acid on brown/beige adipocyte differentiation and lipid metabolism in preadipocytes 3T3-L1 MBX.
Methods: The brown cocktail method was employed to induce 3T3-L1 MBX cells to differentiate into beige adipocytes. The impact of pachymic acid on the viability of 3T3-L1 MBX preadipocytes was evaluated using the CCK-8 assay.
Phytomedicine
December 2024
Department of Science in Korean Medicine, Graduate School, Kyung Hee University, 02447, Seoul, South Korea; Department of Pharmacology, College of Korean Medicine, Kyung Hee University, 02447, Seoul, South Korea; Kyung Hee Institute of Convergence Korean Medicine, Kyung Hee University, 02447, Seoul, South Korea. Electronic address:
Background: Beige adipocytes have physiological functions similar to brown adipocytes, which are available to increase energy expenditure through uncoupling protein 1 (UCP1) within mitochondria. Recently, many studies showed white adipocytes can undergo remodeling into beige adipocytes, called "browning", by increasing fusion and fission events referred to as mitochondrial dynamics.
Purpose: In this study, we aimed to investigate the browning effects of 4-hydroxybenzoic acid (4-HA), one of the major compounds of black raspberries.
Biomed Pharmacother
January 2025
Department of Physiology, Institute for Medical Sciences, Jeonbuk National University Medical School, Jeonju, Jeollabuk-do 54907, South Korea. Electronic address:
Compound K (CK), an active ingredient in ginseng, has anti-cancer, anti-inflammatory, and antioxidant properties. However, its effects on thermogenesis and mitochondrial dynamics in white adipose tissue (WAT) adipocytes are not well understood. This study explores CK's impact on thermogenesis and mitochondrial metabolism in cold-exposed mice and mouse stromal vascular fraction (SVF) cells.
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January 2025
Department of Radiology, C.J. Gorter MRI Center, Leiden University Medical Center, Leiden, The Netherlands.
Brown adipose tissue (BAT) is a metabolically highly active tissue that dissipates energy stored within its intracellular triglyceride droplets as heat. Others have previously utilized MRI to show that the fat fraction of human supraclavicular BAT (scBAT) decreases upon cold exposure, compared with baseline (i.e.
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