College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
Cells. 2023 May 15;12(10):1393. doi: 10.3390/cells12101393.
Adiponectin (APN) is an essential adipokine for a variety of reproductive processes. To investigate the role of APN in goat corpora lutea (CLs), CLs and sera from different luteal phases were collected for analysis. The results showed that the APN structure and content had no significant divergence in different luteal phases both in CLs and sera; however, high molecular weight APN was dominant in serum, while low molecular weight APN was more present in CLs. The luteal expression of both AdipoR1/2 and T-cadherin (T-Ca) increased on D11 and 17. APN and its receptors (AdipoR1/2 and T-Ca) were mainly expressed in goat luteal steroidogenic cells. The steroidogenesis and APN structure in pregnant CLs had a similar model as in the mid-cycle CLs. To further explore the effects and mechanisms of APN in CLs, steroidogenic cells from pregnant CLs were isolated to detect the AMPK-mediated pathway by the activation of APN (AdipoRon) and knockdown of APN receptors. The results revealed that P-AMPK in goat luteal cells increased after incubation with APN (1 μg/mL) or AdipoRon (25 μM) for 1 h, and progesterone (P4) and steroidogenic proteins levels (STAR/CYP11A1/HSD3B) decreased after 24 h. APN did not affect the steroidogenic protein expression when cells were pretreated with Compound C or SiAMPK. APN increased P-AMPK and reduced the CYP11A1 expression and P4 levels when cells were pretreated with SiAdipoR1 or SiT-Ca, while APN failed to affect P-AMPK, the CYP11A1 expression or the P4 levels when pretreated with SiAdipoR2. Therefore, the different structural forms of APN in CLs and sera may possess distinct functions; APN might regulate luteal steroidogenesis through AdipoR2 which is most likely dependent on AMPK.
脂联素（APN）是多种生殖过程中必不可少的脂肪细胞因子。为了研究 APN 在山羊黄体（CL）中的作用，收集了不同黄体期的 CL 和血清进行分析。结果表明，CL 和血清中不同黄体期的 APN 结构和含量没有明显差异；然而，高分子量 APN 在血清中占优势，而低分子量 APN 在 CL 中更为常见。AdipoR1/2 和 T-钙黏蛋白（T-Ca）在 D11 和 17 时黄体表达增加。APN 及其受体（AdipoR1/2 和 T-Ca）主要在山羊黄体甾体生成细胞中表达。妊娠 CL 中的甾体生成和 APN 结构与中期 CL 中的相似。为了进一步探讨 APN 在 CL 中的作用和机制，从妊娠 CL 中分离出甾体生成细胞，通过 APN（AdipoRon）的激活和 APN 受体的敲低来检测 AMPK 介导的途径。结果表明，在孵育 1 小时后，山羊黄体细胞中的 P-AMPK 在加入 APN（1 μg/mL）或 AdipoRon（25 μM）后增加，而在 24 小时后，孕酮（P4）和甾体生成蛋白水平（STAR/CYP11A1/HSD3B）降低。当细胞用 Compound C 或 SiAMPK 预处理时，APN 不影响甾体生成蛋白的表达。当细胞用 SiAdipoR1 或 SiT-Ca 预处理时，APN 增加 P-AMPK，降低 CYP11A1 表达和 P4 水平，而当用 SiAdipoR2 预处理时，APN 不能影响 P-AMPK、CYP11A1 表达或 P4 水平。因此，CL 和血清中 APN 的不同结构形式可能具有不同的功能；APN 可能通过 AdipoR2 调节黄体甾体生成，而 AdipoR2 可能依赖于 AMPK。
