Palak Ewelina, Ponikwicka-Tyszko Donata, Pulawska-Moon Kamila, Sztachelska Maria, Milewska Gabriela, Modzelewska Beata, Kleszczewski Tomasz, Koivukoski Maria L, Bernaczyk Piotr, Hady Hady Razak, Gołaszewski Piotr, Lupinska Aleksandra N, Kulikowski Marek, Lemancewicz Adam, Huhtaniemi Ilpo T, Wolczynski Slawomir, Rahman Nafis A
Department of Biology and Pathology of Human Reproduction, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn, 10-748, Poland.
Institute of Biomedicine, Research Centre for Integrative Physiology and Pharmacology, University of Turku, Turku, 20520, Finland.
Mol Med. 2024 Dec 4;30(1):241. doi: 10.1186/s10020-024-01015-2.
Extragonadal follicle-stimulating hormone receptor (FSHR) expression at low levels has been shown in several normal and tumor tissues, including myometrium and adipose tissue. FSH-FSHR signaling in the myometrium has been suggested to regulate uterine contractile activity and the timing of labor. In contrast, FSH-FSHR has been linked to the activation of brown/beige fat thermogenesis in adipose tissue. The issue of extragonadal FSHR expression and its functionality remains contentious within the scientific community, as contradictory findings necessitate further independent and critical analyses. Hereby, we re-investigated the FSHR expression and its functionality in normal non-pregnant (M-NP) and pregnant (N-P) human myometrium, as well as in human visceral (VAT) and subcutaneous (SCAT) adipose tissue (AT).
FSHR expression at mRNA (real-time qPCR, RNAscope in situ hybridization) and protein (immunohistochemical staining) levels in adipose tissue, myometrium, and adipocytes were evaluated. Myometrium and adipocytes were treated with recombinant (rh)FSH to study its effects on functional pathways. Myometrium contractile activity was measured using a force transducer with digital output and the DASYLab software unit. Cyclic adenosine monophosphate (cAMP) production by myometrium explants and adipocytes was measured using a cAMP ELISA Kit. The activation of the AKT pathway in myometrium and adipocytes was analyzed by Western blot analysis.
Contrary to previous observations, we found no expression of FSHR at either mRNA or protein levels in M-NP, N-P, VAT, and SCAT. Treatment with recombinant human FSH (rhFSH) showed no effect on cAMP production or phosphorylation of AKT in M-NP, N-P, as well as in VAT and SCAT. rhFSH treatment did not influence contractile activity in M-NP, N-P.
These findings suggest that the FSHR signaling pathway does not regulate myometrial contractility during pregnancy. Additionally, the absence of FSHR expression in both VAT and SCAT implied that FSHR does not play a role in the functional signaling pathways in adipose tissues. In conclusion, our findings contradict earlier data on the involvement of FSH-FSHR signaling in regulating myometrial contractility near term, as well as in adipose tissue function.
在包括子宫肌层和脂肪组织在内的多种正常组织和肿瘤组织中，已发现性腺外促卵泡激素受体（FSHR）呈低水平表达。子宫肌层中的FSH-FSHR信号传导被认为可调节子宫收缩活动和分娩时间。相比之下，FSH-FSHR与脂肪组织中棕色/米色脂肪产热的激活有关。由于相互矛盾的研究结果需要进一步独立和严谨的分析，性腺外FSHR表达及其功能问题在科学界仍存在争议。在此，我们重新研究了FSHR在正常非妊娠（M-NP）和妊娠（N-P）人子宫肌层以及人内脏（VAT）和皮下（SCAT）脂肪组织（AT）中的表达及其功能。
评估了脂肪组织、子宫肌层和脂肪细胞中FSHR在mRNA（实时定量PCR、RNAscope原位杂交）和蛋白质（免疫组织化学染色）水平的表达。用重组（rh）FSH处理子宫肌层和脂肪细胞，以研究其对功能途径的影响。使用带有数字输出的力传感器和DASYLab软件单元测量子宫肌层的收缩活动。使用cAMP ELISA试剂盒测量子宫肌层外植体和脂肪细胞中环状单磷酸腺苷（cAMP）的产生。通过蛋白质印迹分析子宫肌层和脂肪细胞中AKT途径的激活情况。
与先前的观察结果相反，我们发现在M-NP、N-P、VAT和SCAT中，FSHR在mRNA或蛋白质水平均无表达。用重组人FSH（rhFSH）处理对M-NP、N-P以及VAT和SCAT中的cAMP产生或AKT磷酸化均无影响。rhFSH处理不影响M-NP、N-P中的收缩活动。
这些发现表明，FSHR信号通路在妊娠期间不调节子宫肌层的收缩性。此外，VAT和SCAT中均不存在FSHR表达，这意味着FSHR在脂肪组织的功能信号通路中不起作用。总之，我们的发现与早期关于FSH-FSHR信号传导参与调节足月子宫肌层收缩性以及脂肪组织功能的数据相矛盾。
