Hongyun Lu1, Xiaofeng Li2, Panwei Mu2, Baiying Qian3, Wei Jiang2, Longyi Zeng4. 1. Department of Endocrinology & Metabolism, the Third Affiliated Hospital of Sun Yat-sen University, Guangdong, Guangzhou 510630, China; Department of Endocrinology & Metabolism, the Fifth Affiliated Hospital of Sun Yat-sen University, Guangdong, Zhuhai 519000, China. 2. Department of Endocrinology & Metabolism, the Third Affiliated Hospital of Sun Yat-sen University, Guangdong, Guangzhou 510630, China. 3. Department of Nephrology, the Fifth Affiliated Hospital of Sun Yat-sen University, Guangdong, Zhuhai 519000, China. 4. Department of Endocrinology & Metabolism, the Third Affiliated Hospital of Sun Yat-sen University, Guangdong, Guangzhou 510630, China. Electronic address: ly_zeng@yeah.net.
Abstract
OBJECTIVE: Dickkopf-1, a newly recognized antagonist for canonical Wnt signaling, is secreted in the early stage of human adipose-derived stem cells (ASCs) adipogenic differentiation. This study was aimed to investigate whether human recombinant DKK-1 (rhDKK-1) could affect the differentiation and metabolism as well as adipocytokines secretion in primary cultured human ASCs. METHODS: Human ASCs were isolated from omental adipose tissue and induced to adipogenic differentiation in the absence or presence of Wnt signaling antagonist rhDKK-1 and agonist SB216763, respectively. mRNA and protein expression profiles of adipogenic factors during the differentiation process were analyzed using quantitative RT-PCR and Western blotting. Adipocytokines secretion levels in the culture medium were measured by ELISA method. RESULTS: Our results showed that DKK-1 was already expressed during the early stage of adipogenesis and reached the peak on the 9th day. Exogenous rhDKK-1 exposure accelerated the differentiation by up-regulating PPAR-γ and C/EBP-α, down-regulating Wnt3a, Wnt10b and β-catenin, without affecting non-canonical Wnt signaling marker (Wnt5a). In addition, rhDKK-1 treatment increased the secretion of leptin, RBP4, TNF-α and adiponectin during differentiation. rhDKK-1 treatment also significantly increased the intracellular accumulation of lipids and lipolysis. Thus, Wnt signal pathway agonist SB216763 down-regulated DKK-1 transcriptional and secretion levels during adipogenic process. CONCLUSIONS: Our results suggest that rhDKK-1 could promote ASCs differentiation and increase adipocytokines secretion via canonical Wnt signaling pathway.
OBJECTIVE:Dickkopf-1, a newly recognized antagonist for canonical Wnt signaling, is secreted in the early stage of human adipose-derived stem cells (ASCs) adipogenic differentiation. This study was aimed to investigate whether human recombinant DKK-1 (rhDKK-1) could affect the differentiation and metabolism as well as adipocytokines secretion in primary cultured human ASCs. METHODS:Human ASCs were isolated from omental adipose tissue and induced to adipogenic differentiation in the absence or presence of Wnt signaling antagonist rhDKK-1 and agonist SB216763, respectively. mRNA and protein expression profiles of adipogenic factors during the differentiation process were analyzed using quantitative RT-PCR and Western blotting. Adipocytokines secretion levels in the culture medium were measured by ELISA method. RESULTS: Our results showed that DKK-1 was already expressed during the early stage of adipogenesis and reached the peak on the 9th day. Exogenous rhDKK-1 exposure accelerated the differentiation by up-regulating PPAR-γ and C/EBP-α, down-regulating Wnt3a, Wnt10b and β-catenin, without affecting non-canonical Wnt signaling marker (Wnt5a). In addition, rhDKK-1 treatment increased the secretion of leptin, RBP4, TNF-α and adiponectin during differentiation. rhDKK-1 treatment also significantly increased the intracellular accumulation of lipids and lipolysis. Thus, Wnt signal pathway agonist SB216763 down-regulated DKK-1 transcriptional and secretion levels during adipogenic process. CONCLUSIONS: Our results suggest that rhDKK-1 could promote ASCs differentiation and increase adipocytokines secretion via canonical Wnt signaling pathway.
Authors: M Chiarito; L Piacente; N Chaoul; P Pontrelli; G D'Amato; A Grandone; G Russo; M E Street; M G Wasniewska; G Brunetti; M F Faienza Journal: J Endocrinol Invest Date: 2022-03-02 Impact factor: 5.467