Regulation of Secreted Protein Acidic and Rich in Cysteine during Adipose Conversion and Adipose Tissue Hyperplasia*

Autor: Philippe Valet, Marie-Noëlle Monthouël-Kartmann, Isabelle Castan-Laurell, Emmanuel Van Obberghen, Jeremie Boucher, Sophie Tartare-Deckert, E. Helene Sage, Carine Chavey
Přispěvatelé: Institut National de la Santé et de la Recherche Médicale U145, IFR 50, Avenue de Valombrose, 06107 Nice Cédex 2, France
Jazyk: angličtina
Rok vydání: 2006
Předmět:
Zdroj: Obesity
Obesity, Wiley, 2006, 14 (11), pp.1890-1897. ⟨10.1038/oby.2006.220⟩
ISSN: 1930-7381
Popis: Objective: To explore the regulation of secreted protein acidic and rich in cysteine (SPARC) expression and its role in adipose tissue. Research Methods and Procedures: We studied the regulation of SPARC expression in transgenic mice expressing the human β3 and α2 adrenergic receptors on a murine β3 adrenergic receptor null background that became obese under a high-fat diet mainly as a result of adipose tissue hyperplasia. Furthermore, we analyzed its expression in human adipose tissue and its regulation during adipocyte differentiation. Results: SPARC protein in adipose tissue was increased in obese transgenic mice compared with control mice, indicating that SPARC expression was associated with adipose tissue hyperplasia. Both SPARC mRNA and protein were detected in human adipose tissue. Comparing adipocytes and vascular stroma, we found that SPARC expression was mainly associated with the adipocyte fraction. Consistent with this, SPARC transcript increased during differentiation of human primary preadipocytes. 3T3-L1 preadipocytes showed an increase in SPARC expression in differentiated cells but with biphasic expression during the process. After induction in committed cells, SPARC mRNA and protein levels declined as differentiation began and returned to elevated levels in fully differentiated adipocytes. Discussion: SPARC expression correlated with adipose tissue hyperplasia and adipogenesis. Therefore, SPARC seems to play a role in adipose tissue physiology as it is involved in growth and differentiation.
Databáze: OpenAIRE