Elevated endogenous estrogens stimulate human uterine artery endothelial cell (hUAEC) hydrogen sulfide (H₂S) production by selectively upregulating the expression of H₂S synthesizing enzyme cystathionine β-synthase (CBS), but the underlying mechanisms are underdetermined. We hypothesized that CBS transcription mediates estrogen-stimulated pregnancy-dependent hUAEC H₂S production. Estradiol-17β (E₂β) stimulated CBS but not cystathionine γ-lyase (CSE) expression in pregnant human uterine artery ex vivo, which was attenuated by the estrogen receptor (ER) antagonist ICI 182,780. E₂β stimulated CBS mRNA/protein and H₂S production in primary hUAEC from nonpregnant and pregnant women, but with greater responses in pregnant state; all were blocked by ICI 182,780. Human CBS promoter contains multiple estrogen-responsive elements (EREs), including one ERE preferentially binding ERα (αERE) and three EREs preferentially binding ERβ (βERE), and one full ERE (α/βERE) and one half ERE (½α/βERE) binding both ERα and ERβ. Luciferase assays using reporter genes driven by human CBS promoter with a series of 5′-deletions identified the α/βEREs binding both ERα and ERβ (α/βERE and ½α/βERE) to be important for baseline and E₂β-stimulated CBS promoter activation. E₂β stimulated ERα/ERβ heterodimerization by recruiting ERα to α/βEREs and βERE, and ERβ to βERE, α/βEREs, and αERE. ERα or ERβ agonist alone trans-activated CBS promoter, stimulated CBS mRNA/protein and H₂S production to levels comparable to that of E₂β-stimulated, while ERα or ERβ antagonist alone abrogated E₂β-stimulated responses. E₂β did not change human CSE promoter activity and CSE mRNA/protein in hUAEC. Altogether, estrogen-stimulated pregnancy-dependent hUAEC H₂S production occurs by selectively upregulating CBS expression via ERα/ERβ-directed gene transcription.

_{升高的内源性雌激素通过选择性上调H 2} S合成酶胱硫醚β-合酶(CBS)的表达来刺激人子宫动脉内皮细胞(hUAEC)产生硫化氢(H _{2 S)，但其潜在机制尚不清楚。}我们假设CBS转录介导雌激素刺激的妊娠依赖性 hUAEC H ₂ S 产生。雌二醇-17β (E _{2 β) 刺激离体妊娠人子宫}动脉中的 CBS，但不刺激胱硫醚 γ-裂解酶 (CSE) 的表达，雌激素受体 (ER) 拮抗剂 ICI 182,780 可减弱这种表达。E ₂ β刺激非妊娠和妊娠女性原代hUAEC中CBS mRNA/蛋白和H _{2 S的产生，但在妊娠状态下反应更大；}全部被 ICI 182,780 屏蔽。人CBS启动子含有多种雌激素反应元件（ERE），包括1个优先结合ERα（αERE）的ERE和3个优先结合ERβ（βERE）的ERE，以及1个全ERE（α/βERE）和1个半ERE（½α/βERE）结合 ERα 和 ERβ。使用由具有一系列 5'-缺失的人类 CBS 启动子驱动的报告基因进行荧光素酶测定，确定结合 ERα 和 ERβ 的 α/βERE（α/βERE 和 ½α/βERE）对于基线和 E 2 β 刺激的CBS_启动子非常重要激活。E ₂ β 通过将 ERα 募集到 α/βERE 和 βERE，以及将 ERβ 募集到 βERE、α/βERE 和 αERE 来刺激 ERα/ERβ 异二聚化。单独的ERα或ERβ激动剂反式激活CBS启动子，刺激CBS mRNA/蛋白和H _{2 S产生至与E 2} β刺激的水平相当的水平，而单独的ERα或ERβ拮抗剂消除E ₂ β刺激的反应。E ₂ β不改变hUAEC中的人CSE启动子活性和CSE mRNA/蛋白质。总而言之，雌激素刺激的妊娠依赖性 hUAEC H ₂ S 产生是通过 ERα/ERβ 指导的基因转录选择性上调 CBS 表达而发生的。