Luteinizing hormone-induced Akt phosphorylation and androgen production are modulated by MAP Kinase in bovine theca cells.
Luteinizing hormone-induced Akt phosphorylation and androgen production are modulated by MAP Kinase in bovine theca cells.
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DOI：
10.1186/1757-2215-2-17
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发表时间：
2009-11-16
影响因子：
4
通讯作者：
Kotsuji F
中科院分区：
文献类型：
--
作者：
Fukuda S;Orisaka M;Tajima K;Hattori K;Kotsuji F
卵泡膜细胞通过为颗粒细胞雌激素的合成提供芳香化雄激素，在控制卵巢类固醇合成中起重要作用。虽然已经确定卵泡膜细胞的类固醇生成活性主要受LH调节，但调节卵泡膜增殖和/或类固醇生成的细胞内信号转导机制仍然不清楚。在这项研究中，我们研究了LH是否以及如何控制PI 3 K/Akt信号通路和牛卵泡膜细胞雄激素的产生。我们还探讨了LH诱导的PI 3 K/Akt激活是否与其他信号通路（即PKA和MAPK）有关。从牛小窦卵泡中分离卵巢卵泡膜细胞，并与LH孵育不同的时间。Western blotting检测卵泡膜细胞中磷酸化Akt和总Akt含量。使用EIA测定用过的培养基中的雄烯二酮水平。半定量RT-PCR分析卵泡膜细胞中CYP 17 A1和星星的mRNA水平。为了检查Akt活性是否参与卵泡膜细胞雄激素的产生，还将PI 3 K抑制剂渥曼青霉素和LY 294002添加到细胞中。Akt是组成型表达的，但在培养的牛卵泡膜细胞中通过暴露于LH而逐渐磷酸化。LH显着增加牛卵泡膜细胞中的雄烯二酮的生产，而除了渥曼青霉素和LY 294002显着降低LH诱导的雄烯二酮的生产。LH显著增加卵泡膜细胞中CYP 17 A1 mRNA水平，而加入LY 294002显著降低LH诱导的CYP 17 A1表达。LH和PI 3 K抑制剂均不改变卵泡膜细胞中星星的mRNA水平。虽然H89（PKA的选择性抑制剂）不影响LH介导的Akt变化，但U 0126（有效的MEK抑制剂）抑制LH诱导的Akt磷酸化，CYP 17 A1表达和卵泡膜细胞中雄激素的产生。这些结果表明，LH通过激活PI 3 K/Akt途径刺激卵泡膜细胞中CYP 17 mRNA表达和雄激素产生。LH诱导的牛卵泡膜细胞Akt磷酸化和雄激素的产生受MAPK信号的调节。
Theca cells play an important role in controlling ovarian steroidogenesis by providing aromatizable androgens for granulosa cell estrogen biosynthesis. Although it is well established that the steroidogenic activity of theca cells is mainly regulated by LH, the intracellular signal transduction mechanisms that regulate thecal proliferation and/or steroidogenesis remain obscure. In this study, we examined whether and how LH controls the PI3K/Akt signaling pathway and androgen production in bovine theca cells. We also explored whether this LH-induced PI3K/Akt activation is modulated with other signaling pathways (i.e. PKA and MAPK). Ovarian theca cells were isolated from bovine small antral follicles and were incubated with LH for various durations. Phospho-Akt and total-Akt content in the cultured theca cells were examined using Western blotting. Androstenedione levels in the spent media were determined using EIA. Semi-quantitative RT-PCR analyses were conducted to analyze the mRNA levels of CYP17A1 and StAR in the theca cells. To examine whether Akt activity is involved in theca cell androgen production, the PI3K inhibitors wortmannin and LY294002 were also added to the cells. Akt is constitutively expressed, but is gradually phosphorylated in cultured bovine theca cells through exposure to LH. LH significantly increased androstenedione production in bovine theca cells, whereas addition of the wortmannin and LY294002 significantly decreased LH-induced androstenedione production. LH significantly increased CYP17A1 mRNA level in theca cells, whereas addition of LY294002 significantly decreased LH-induced CYP17A1 expression. Neither LH nor PI3K inhibitors alter the mRNA levels of StAR in theca cells. Although H89 (a selective inhibitor of PKA) does not affect LH-mediated changes in Akt, U0126 (a potent MEK inhibitor) suppressed LH-induced Akt phosphorylation, CYP17A1 expression, and androgen production in theca cells. These results indicate that LH stimulates CYP17 mRNA expression and androgen production in theca cells via activation of the PI3K/Akt pathway. The LH-induced Akt phosphorylation and androgen production are modulated by the MAPK signaling in bovine theca cells.
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影响因子：
56.9
作者：
Kawasaki, H;Springett, GM;Graybiel, AM
通讯作者：
Graybiel, AM
影响因子：
4
作者：
Ryan KE;Glister C;Lonergan P;Martin F;Knight PG;Evans AC
通讯作者：
Evans AC
影响因子：
4.8
作者：
Carvalho, CRO;Carvalheira, JBC;Saad, MJA
通讯作者：
Saad, MJA
影响因子：
4.8
作者：
Cass, LA;Meinkoth, JL
通讯作者：
Meinkoth, JL
影响因子：
5.3
作者：
Dremier, S;Pohl, V;Maenhaut, C
通讯作者：
Maenhaut, C