Maija Vaittinen1, Marjukka Kolehmainen1, Mikael Rydén2, Matti Eskelinen3, Martin Wabitsch4, Jussi Pihlajamäki1,5, Matti Uusitupa1,6, Leena Pulkkinen1. 1. Department of Clinical Nutrition, University of Eastern Finland, Institute of Public Health and Clinical Nutrition, Kuopio, Finland. 2. Department of Medicine (H7), Karolinska Institute, Karolinska University Hospital, Huddinge, Stockholm, Sweden. 3. Department of Surgery, Kuopio University Hospital, Kuopio, Finland. 4. Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, University of Ulm, Ulm, Germany. 5. Departments of Medicine and Clinical Nutrition, Obesity Center, Kuopio University Hospital, Kuopio, Finland. 6. Research Unit, Kuopio University Hospital, Kuopio, Finland.
Abstract
OBJECTIVE: Low-grade inflammation is involved in adipose tissue (AT) and extracellular matrix (ECM) remodeling and induces deposition of ECM proteins in AT. We have previously shown that MFAP5 (microfibrillar-associated protein 5) expression decreases in AT after weight loss. The aim of this study was to investigate MFAP5 localization in human AT and gene expression in adipocytes and the role of MFAP5 in adipocyte metabolism and inflammation. METHODS: MFAP5 protein localization and gene expression were studied with immunohistochemistry and quantitative reverse transcriptase PCR (RT-qPCR) in human subcutaneous AT and cultured Simpson-Golabi-Behmel syndrome (SGBS) adipocytes, respectively. The effect of MFAP5 knock-down by siRNA on gene expression and insulin action was examined with RT-qPCR, western blot, and insulin-stimulated glucose uptake. The effect of different cytokines on MFAP5 gene and protein expression was investigated in cultured human SGBS preadipocytes. RESULTS: MFAP5 protein was highly expressed in AT, and gene expression decreased during adipocyte differentiation in SGBS cells. Treatment of preadipocytes with TNFα and TGFβ1 increased MFAP5 gene and protein expression. Furthermore, MFAP5 knock-down decreased the expression of genes involved in inflammation. CONCLUSIONS: Our results demonstrate that factors involving low-grade inflammation modulate MFAP5 expression and that the modified expression of MFAP5 may further regulate AT inflammation.
OBJECTIVE: Low-grade inflammation is involved in adipose tissue (AT) and extracellular matrix (ECM) remodeling and induces deposition of ECM proteins in AT. We have previously shown that MFAP5 (microfibrillar-associated protein 5) expression decreases in AT after weight loss. The aim of this study was to investigate MFAP5 localization in human AT and gene expression in adipocytes and the role of MFAP5 in adipocyte metabolism and inflammation. METHODS:MFAP5 protein localization and gene expression were studied with immunohistochemistry and quantitative reverse transcriptase PCR (RT-qPCR) in human subcutaneous AT and cultured Simpson-Golabi-Behmel syndrome (SGBS) adipocytes, respectively. The effect of MFAP5 knock-down by siRNA on gene expression and insulin action was examined with RT-qPCR, western blot, and insulin-stimulated glucose uptake. The effect of different cytokines on MFAP5 gene and protein expression was investigated in cultured human SGBS preadipocytes. RESULTS:MFAP5 protein was highly expressed in AT, and gene expression decreased during adipocyte differentiation in SGBS cells. Treatment of preadipocytes with TNFα and TGFβ1 increased MFAP5 gene and protein expression. Furthermore, MFAP5 knock-down decreased the expression of genes involved in inflammation. CONCLUSIONS: Our results demonstrate that factors involving low-grade inflammation modulate MFAP5 expression and that the modified expression of MFAP5 may further regulate AT inflammation.
Authors: Adeline Divoux; Katalin Sandor; Dora Bojcsuk; Fanchao Yi; Meghan E Hopf; Joshua S Smith; Balint L Balint; Timothy F Osborne; Steven R Smith Journal: J Endocr Soc Date: 2020-04-08
Authors: Liang-Yu Lin; Sunny Chun Chang; Jim O'Hearn; Simon T Hui; Marcus Seldin; Pritha Gupta; Galyna Bondar; Mario Deng; Raimo Jauhiainen; Johanna Kuusisto; Markku Laakso; Janet S Sinsheimer; Arjun Deb; Christoph Rau; Shuxun Ren; Yibin Wang; Aldons J Lusis; Jessica J Wang; Adriana Huertas-Vazquez Journal: G3 (Bethesda) Date: 2018-11-06 Impact factor: 3.154