Role of extrathyroidal TSHR expression in adipocyte differentiation and its association with obesity
Open Access
- 29 January 2012
- journal article
- research article
- Published by Springer Science and Business Media LLC in Lipids in Health and Disease
- Vol. 11 (1), 17
- https://doi.org/10.1186/1476-511x-11-17
Abstract
Background: Obesity is known to be associated with higher risks of cardiovascular disease, metabolic syndrome, and diabetes mellitus. Thyroid-stimulating hormone (TSHR) is the receptor for thyroid-stimulating hormone (TSH, or thyrotropin), the key regulator of thyroid functions. The expression of TSHR, once considered to be limited to thyrocytes, has been so far detected in many extrathyroidal tissues including liver and fat. Previous studies have shown that TSHR expression is upregulated when preadipocytes differentiate into mature adipocytes, suggestive of a possible role of TSHR in adipogenesis. However, it remains unclear whether TSHR expression in adipocytes is implicated in the pathogenesis of obesity.Methods: In the present study, TSHR expression in adipose tissues from both mice and human was analyzed, and its association with obesity was evaluated.Results: We here showed that TSHR expression was increased at both mRNA and protein levels when 3T3-L1 preadipocytes were induced to differentiate. Knockdown of TSHR blocked the adipocyte differentiation of 3T3-L1 preadipocytes as evaluated by Oil-red-O staining for lipid accumulation and by RT-PCR analyses of PPAR-γ and ALBP mRNA expression. We generated obesity mice (C57/BL6) by high-fat diet feeding and found that the TSHR protein expression in visceral adipose tissues from obesity mice was significantly higher in comparison with the non-obesity control mice (P< 0.05). Finally, the TSHR expression in adipose tissues was determined in 120 patients. The results showed that TSHR expression in subcutaneous adipose tissue is correlated with BMI (body mass index).Conclusion: Taken together, these results suggested that TSHR is an important regulator of adipocyte differentiation. Dysregulated expression of TSHR in adipose tissues is associated with obesity, which may involve a mechanism of excess adipogenesis.Keywords
This publication has 28 references indexed in Scilit:
- A stimulatory TSH receptor antibody enhances adipogenesis via phosphoinositide 3-kinase activation in orbital preadipocytes from patients with Graves' ophthalmopathyJournal of Molecular Endocrinology, 2011
- High fat diet-induced obesity leads to proinflammatory response associated with higher expression of NOD2 proteinNutrition Research and Practice, 2011
- Expression of eotaxin in 3T3-L1 adipocytes and the effects of weight loss in high-fat diet induced obese miceNutrition Research and Practice, 2011
- Epigenetic regulation of adipocyte differentiation and adipogenesisJournal of Zhejiang University-SCIENCE B, 2010
- Presence of thyrotropin receptor in hepatocytes: not a case of illegitimate transcriptionJournal of Cellular and Molecular Medicine, 2009
- Studies in Mice Deficient for the Autoimmune Regulator (Aire) and Transgenic for the Thyrotropin Receptor Reveal a Role for Aire in Tolerance for Thyroid AutoantigensEndocrinology, 2009
- TSH stimulates adipogenesis in mouse embryonic stem cellsJournal of Endocrinology, 2007
- Biological Effects of Thyrotropin Receptor Activation on Human Orbital PreadipocytesPublished by Association for Research in Vision and Ophthalmology (ARVO) ,2006
- Effect of BMI and age on adipose tissue cellularity and differentiation capacity in womenInternational Journal of Obesity, 2003
- Functional Expression of Thyrotropin Receptor in Differentiated 3T3-L1 Cells: A Possible Model Cell Line of Extrathyroidal Expression of Thyrotropin ReceptorBiochemical and Biophysical Research Communications, 1996