Zhu Ye, Wei Junxiu, Yang Xin, Zhu Wei
Department of Obstetrics and Gynecology, Peking University People's Hospital, Beijing, China.
Department of Reproductive Medicine, Affiliated Hospital of Hebei University, Baoding, China.
Front Pharmacol. 2025 Jan 28;16:1496393. doi: 10.3389/fphar.2025.1496393. eCollection 2025.
This study aimed to investigate the underlying mechanisms involved in the cardioprotective effects of dehydroepiandrosterone (DHEA) on endoplasmic reticulum stress (ERS) -mediated apoptosis in human vascular smooth muscle cells (HVSMCs) and human umbilical vein endothelial cells (HUVECs).
Various concentrations of Dithiothreitol (DTT) were used to induce ERS-mediated apoptosis. DHEA was utilized to inhibit the apoptotic effects of DTT, while estrogen receptor (ER) antagonists ICI 182,780 and G15, the androgen receptor (AR) antagonist flutamide and the aromatase inhibitor letrozole were used to identify the receptors activated during DHEA treatment in HVSMCs and HUVECs. Flow cytometry assessed the apoptotic rate, and Western blotting analysis evaluated the expression levels of ERS-related proteins GRP78 and PERK, and the apoptotic protein marker CHOP. Furthermore, the primary receptor signaling pathways were identified using signaling pathway blockers: LY294002 (PI3K blocker), SP600125 (JNK blocker), and U0126 (ERK1/2 blocker).
In the DTT pretreatment group (0.8 mmol/L, for 8 h), the expressions of GRP78 and CHOP were significantly up regulated, indicating that an optimal ERS model was successfully established. Additionally, 10-4 mmol/L DHEA significantly inhibited the DTT-induced upregulation of GRP78 and CHOP. The results also demonstrated that the apoptotic rate in the DTT group was increased, while DHEA significantly reduced this rate. The addition of ER antagonists ICI 182,780 and G15 to HVSMCs reversed the effects of DHEA; however, the aromatase inhibitor letrozole and the AR antagonist flutamide did not reverse this effect. Notably, the use of the JNK inhibitor SP600125, the PI3K inhibitor LY294002, and the ERK1/2 inhibitor U0126 antagonized the protective effects of DHEA, with SP600125 showing the most significant impact on both HVSMCs and HUVECs.
Our study has identified a novel mechanism underlying the cardioprotective effects of DHEA. Specifically, DHEA may mitigate ERS-induced cell apoptosis by activating estrogen receptors ERα, ERβ, and GPER via the activated JNK pathway.
本研究旨在探讨脱氢表雄酮（DHEA）对人血管平滑肌细胞（HVSMCs）和人脐静脉内皮细胞（HUVECs）内质网应激（ERS）介导的凋亡产生心脏保护作用的潜在机制。
使用不同浓度的二硫苏糖醇（DTT）诱导ERS介导的凋亡。利用DHEA抑制DTT的凋亡作用，同时使用雌激素受体（ER）拮抗剂ICI 182,780和G15、雄激素受体（AR）拮抗剂氟他胺以及芳香化酶抑制剂来曲唑，以确定HVSMCs和HUVECs在DHEA处理过程中激活的受体。流式细胞术评估凋亡率，蛋白质免疫印迹分析评估ERS相关蛋白GRP78和PERK以及凋亡蛋白标志物CHOP的表达水平。此外，使用信号通路阻滞剂LY294002（PI3K阻滞剂）、SP600125（JNK阻滞剂）和U0126（ERK1/2阻滞剂）确定主要受体信号通路。
在DTT预处理组（0.8 mmol/L，处理8小时）中，GRP78和CHOP的表达显著上调，表明成功建立了最佳的ERS模型。此外，10-4 mmol/L DHEA显著抑制了DTT诱导的GRP78和CHOP上调。结果还表明，DTT组的凋亡率增加，而DHEA显著降低了该比率。向HVSMCs中添加ER拮抗剂ICI 182,780和G15可逆转DHEA的作用；然而，芳香化酶抑制剂来曲唑和AR拮抗剂氟他胺并未逆转此作用。值得注意的是，使用JNK抑制剂SP600125、PI3K抑制剂LY294002和ERK1/2抑制剂U0126可拮抗DHEA的保护作用，其中SP600125对HVSMCs和HUVECs的影响最为显著。
我们的研究确定了DHEA心脏保护作用的一种新机制。具体而言，DHEA可能通过激活JNK途径激活雌激素受体ERα、ERβ和GPER，从而减轻ERS诱导的细胞凋亡。
