Fig. 5

Fig. 5 Bmp8a activates Smad2/3 signaling to inhibit adipocyte differentiation in 3T3-L1 cells.

a–d Representative western blot analysis and quantification of changes in p-Smad1/5/8, p-Smad2/3, p-ERK1/2, p-p38 MAPK, and p-JNK expression in LV-bmp8a cells (a, b) or LV-Bmp8a cells (c, d). Protein expression levels were quantified using ImageJ software and normalized to the amount of total protein (n = 3). e, f Representative Oil Red O staining photographs of LV-bmp8a and LV-Bmp8a 3T3-L1 cells were induced to adipogenic in the presence of DMH1 or TP0427736 HCL, dimethylsulfoxide (DMSO) as a vehicle and subjected to OD₄₉₂ quantifications (n = 3). Scale bar = 20 µm. g Schematic diagram of BMP8 mediated signal transduction. BMP8 can activate Smad1/5/8 signal transduction through the receptor complex formed by type I receptor ALK2, ALK3, or ALK6 and type II receptor ACVR2A or BMPR2. Meanwhile, BMP8 can also activate Smad2/3 signal transduction through the receptor complex formed by type I receptors ALK4 or ALK5 and type II receptors ACVR2A, ACVR2B, or TGFBR2. h Non-expression of mouse Alk6 gene in 3T3-L1 cells (n = 3). i The qPCR quantification of the type I receptor (Alk2, Alk3, Alk4, Alk5, Alk7) and type II receptor (Acvr2a, Acvr2b, Bmpr2, Tgrβr2) transcripts expressed in 3T3-L1 cells (n = 3). j, k Quantification of the activity of BRE-driven luciferase reporters with pCMV-bmp8a (j) or pCMV-Bmp8a (k) cotransfected with pCMV-Alk2, pCMV-Alk3, pCMV-Bmpr2, pCMV-Acrv2a, respectively (n = 3). Renilla luciferase was used as the internal control. l, m Quantification of the activity of CAGA-driven luciferase reporters with pCMV-bmp8a (l) or pCMV-Bmp8a (m) cotransfected with pCMV-Alk2, pCMV-Alk3, pCMV-Bmpr2, and pCMV-Acrv2a, respectively (n = 3). Renilla luciferase was used as the internal control. Data were representative of at least three independent experiments. Data were analyzed by One-way ANOVA and presented as mean ± SD (ns not significant, *p < 0.05, **p < 0.01, ***p < 0.001).