Endothelin-1 stimulates suppressor of cytokine signaling-3 gene expression in adipocytes

Autor: Chun Hsiung Huang, Yung Hsi Kao, Low Tone Ho, Hsin Huei Chang, Ya Chu Tang, Chi Peng Wu, Yow Chii Kuo, Chi Wei Liu, Yao Ming Huang, Liang Yi Wu
Rok vydání: 2012
Předmět:
Zdroj: General and Comparative Endocrinology. 178:450-458
ISSN: 0016-6480
DOI: 10.1016/j.ygcen.2012.06.024
Popis: Endothelin (ET)-1 and suppressor of cytokine signaling (SOCS)-3 were respectively found to regulate energy metabolism and hormone signaling in fat cells. Although ET-1 can also regulate the expression of SOCS-3-stimulating hormones, it is still unknown whether ET-1 regulates SOCS-3 gene expression. This study investigated the pathways involved in ET-1's modulation of SOCS-3 gene expression in 3T3-L1 adipocytes. ET-1 upregulated SOCS-3 mRNA and protein expression in dose- and time-dependent manners. The concentration of ET-1 that increased SOCS-3 mRNA levels by 250-400% was ∼100nM with 2-4h of treatment. Treatment with actinomycin D prevented ET-1-stimulated SOCS-3 mRNA expression, suggesting that the effect of ET-1 requires new mRNA synthesis. Pretreatment with the ET type A receptor (ET(A)R) antagonist, BQ-610, but not the ET type B receptor (ET(B)R) antagonist, BQ-788, prevented the stimulatory effect of ET-1 on SOCS-3 gene expression. The specific inhibitors of either MEK1 (U-0126 and PD-98059), JAK (AG-490), JNK (SP-600125), or PI3K (LY-294002 and wortmannin) reduced ET-1-increased levels of SOCS-3 mRNA and respectively inhibited ET-1-stimulated activities of MEK1, JAK, JNK, and PI3K. These results imply that the ET(A)R, ERK, JAK, JNK, and PI3K are functionally necessary for ET-1's stimulation of SOCS-3 gene expression. Moreover, ET-1 was observed to upregulate expressions of SOCS-1, -2, -3, -4, -5, and -6 mRNAs, but not SOCS-7 or cytokine-inducible SH2-containing protein-1 mRNAs. This suggests that ET-1 selectively affects particular types of SOCS family members. Changes in SOCS gene expressions induced by ET-1 may help explain the mechanism by which ET-1 modulates hormone signaling of adipocytes.
Databáze: OpenAIRE