Fig. 6: sLZIP regulates the crosstalk between OBs and OCs by inducing coupling factors.
a–d, BMMs isolated from WT and sLZIP TG mice were seeded into 12-well culture plates at a density of 1.5 × 105 cells/well and cultured for 7 days in α-MEM containing 50 ng/ml RANKL and 30 ng/ml M-CSF, then mRNA expression levels were determined via qRT‒PCR analysis with β-actin used as an internal control (a); protein expression levels were determined using western blotting (b); SPHK1 activity was determined in 30 μg of cell lysate (c) and S1P levels were analyzed via an ELISA kit (d). e, ADS cells derived from WT mice were exposed to differentiated OC-CM from WT and sLZIP TG mice. Protein expression levels were determined using western blotting. f, ADS cells were cultured with OC-CM from TG or JTE-013 cells (0, 1 or 2 μM) for 24 h. Protein levels were detected using western blotting. β-Actin was used as an internal control. g, ADS cells derived from WT and sLZIP TG mice were seeded into 12-well culture plates at a density of 8 × 104 cells/well and differentiated into OBs for 3 days. The mRNA expression level was determined via qRT‒PCR analysis. All experiments were repeated three times independently. Error bars show the mean ± s.e.m. *P < 0.05, **P < 0.01 and ***P < 0.001 (unpaired, two-tailed Student’s t-test).
