Gong Q.,Chongqing Medical University |
Gong Q.,Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology |
Chen D.,Chinese Academy of Inspection and Quarantine |
Mu Z.,Chongqing Medical University |
Mu Z.,Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology
Food Analytical Methods | Year: 2016
A homogenous light-induced chemiluminescence immunoassay (AlphaLISA) method was established for the determination of residues of zearalanol and its analog zearalanone in muscle tissue samples. AlphaLISA is a bead-based proximity assay. When donor and acceptor beads proximity, a cascade of chemical reactions begin. The end result is a greatly amplified signal that contributes to the detection sensitivity down to the attomole level. Compared with other methods, the AlphaLISA has characteristics of homogeneity, being free of cleaning, high sensitivity. The method showed a linear relationship in the range of 0.01–4 ng/mL (R2 > 0.99); the sensitivity of the assay was 0.066 ng/mL. Cross-reactivity rate of zearalanol was 100 % and zearalanone was 82.1 %, and other compounds were not more than 40 %. The average recovery rates of Zearalanol at spiked levels of 1–4 ng/mL were 96.3 to 105.0 and 91.7 to 100.5 % for pork and bovine muscles; the intra-day precision ranged from 2.6 to 9.8 %, and the inter-day precision ranged from 8.7 to 17.5 %. These results indicated that the proposed method was successfully applied in the analysis of zearalanol and its analog zearalanone in muscle tissues. © 2016 Springer Science+Business Media New York
Liu Y.,Chongqing Medical University |
Liu Y.,Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology |
Zhang R.,Chongqing Medical University |
Zhang R.,Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology |
And 15 more authors.
International Journal of Biochemistry and Cell Biology | Year: 2014
It is known that excessive adipogenesis contributes to osteoporosis, suggesting that trans-differentiation of adipogenic committed preadipocytes into osteoblasts may be a potential therapeutical approach for osteoporosis. We explored whether bone morphogenic protein 9 (BMP9) could induce 3T3-L1 preadipocytes to trans-differentiate into osteoblasts. BMP9 effectively increased expression of osteogenic markers and promoted mineralization in preadipocytes. However, BMP9 also led to adipogenic differentiation of preadipocytes, as evidenced by increased lipid accumulation and up-regulation of adipogenic transcription factors. In order to regulate the switch between osetogenesis and adipogenesis, we evaluated the effect of all-trans retinoic acid (ATRA) on BMP9-induced differentiation of preadipocytes. We found that ATRA enhanced BMP9-induced osteogenic differentiation and blocked BMP9-induced adipogenic differentiation both in vitro and in vivo. Mechanistically, ATRA was shown to elevate BMP9 expression and activate BMP/Smad signaling. Additionally, BMP9 and ATRA exerted a synergistic effect on activation of Wnt/β-catenin signaling. Knockdown of β-catenin abolished the stimulatory effect of ATRA on BMP9-induced alkaline phosphatase activity and reversed the inhibitory effect of ATRA on BMP9-induced adipogenesis in preadipocytes. Furthermore, ATRA and BMP9 synergistically repressed glycogen synthase kinase 3β (GSK3β) activity and promoted Akt phosphorylation, and inhibited expression of phosphatase and tensin homologue deleted on chromosome 10 (PTEN) that antagonizes phosphatidylinositol-3-kinase (PI3K) function, suggesting that Wnt/β-catenin signaling was activated at least partly through PI3K/Akt/GSK3β pathway. Collectively, ATRA mediated BMP9-induced osteogenic or adipogenic differentiation of 3T3-L1 preadipocytes by BMP/Smad and Wnt/β-catenin signaling. The combination of BMP9 and ATRA may be explored as an effective therapeutic strategy for osteoporosis. © 2013 Elsevier Ltd.