Thyroid-Stimulating Hormone Inhibits Insulin Receptor Substrate-1 Expression and Tyrosyl Phosphorylation in 3T3-L1 Adipocytes by Increasing NF-κB DNA-Binding Activity

Figure 3

Factors that affect TNF-α secretion from 3T3-L1 adipocytes. (a) Pretreatment of cells with the PKA inhibitor H89 (10 μM) for 15 minutes before treatment with 1 mIU/ml bovine TSH decreased TNF-α levels. (b) Pretreatment with the nuclear NF-κB inhibitor BAY 11-7082 (5 μM) reduced TSH-stimulated TNF-α production. These results suggested that H89 and BAY 11-7082 inhibited the effect of TSH on TNF-α secretion. The data demonstrated that TSH stimulated 3T3-L1 adipocytes to secrete TNF-α via the cAMP-PKA pathway. The data are presented as the () ().

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