Blitek Agnieszka, Szymanska Magdalena
Institute of Animal Reproduction and Food Research of the Polish Academy of Sciences, Tuwima 10, 10-748, Olsztyn, Poland.
Institute of Animal Reproduction and Food Research of the Polish Academy of Sciences, Tuwima 10, 10-748, Olsztyn, Poland.
Theriogenology. 2019 Mar 15;127:88-101. doi: 10.1016/j.theriogenology.2019.01.002. Epub 2019 Jan 7.
Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear receptor family of ligand-dependent transcription factors. PPARs are important regulators of glucose and fatty acid metabolism, apoptosis, angiogenesis, cell proliferation and differentiation, and immune response. Their possible role in the female reproductive tract was demonstrated. In the present study, cultured luminal epithelial (LE) and stromal (ST) cells of the porcine endometrium were used to examine (1) the effect of conceptus exposed medium (CEM) on mRNA and protein expression and DNA binding activity of PPARA, PPARD, and PPARG isoforms, and (2) the effect of PPARA, PPARD, and PPARG agonists on the expression of selected genes, apoptosis, and cell proliferation. The addition of CEM stimulated PPARA expression and DNA binding activity of this isoform in LE and ST cells (P < 0.05). Increased expression of PPARD mRNA in the presence of CEM was detected in ST cells (P < 0.05), while the concentration of PPARG transcripts decreased in response to CEM in both cell types (P < 0.05). LE and ST cells of the pig endometrium possess PPARA, PPARD, and PPARG proteins, with clear nuclear staining visible predominately in ST cells. In LE cells, activation of PPARG with 15-deoxy-Δ12,14-prostaglandin(PG)J2 down-regulated the expression of genes encoding amino acid transporter 1 (SLC38A1), leukemia inhibitory factor (LIF) and enzymes involved in PG synthesis (P < 0.05). In ST cells, activation of PPARD isoform with both agonists used (L-165,041 and cPGI2) and PPARG isoform with 15-deoxy-Δ12,14-PGJ2 increased vascular endothelial growth factor A (VEGFA) mRNA expression (P < 0.05). Moreover, GW9578 (PPARA agonist) and 15-deoxy-Δ12,14-PGJ2 stimulated glucose transporter 1 (SLC2A1) gene expression in ST cells. 15-deoxy-Δ12,14-PGJ2 was also effective in up-regulation of the ratio of BAX/BCL2 mRNA expression and active caspase-3 concentration in ST cells (P < 0.05). Finally, GW9578 stimulated LE and ST cell proliferation, while rosiglitazone (PPARG agonist) increased the number of viable ST but not LE cells. In conclusion, this study demonstrated that conceptus products differentially modulate PPARs expression and activity in the porcine endometrium. Activation of PPARs may in turn affect nutrient transport, PG synthesis, angiogenesis, apoptosis, or cell proliferation in this tissue. Therefore, PPAR isoforms seem to play an important role in development and function of the porcine uterus.
过氧化物酶体增殖物激活受体（PPARs）是配体依赖性转录因子核受体家族的成员。PPARs是葡萄糖和脂肪酸代谢、细胞凋亡、血管生成、细胞增殖与分化以及免疫反应的重要调节因子。它们在女性生殖道中的可能作用已得到证实。在本研究中，使用猪子宫内膜的培养腔上皮（LE）细胞和基质（ST）细胞来检测：（1）孕体暴露培养基（CEM）对PPARA、PPARD和PPARG亚型的mRNA和蛋白表达以及DNA结合活性的影响；（2）PPARA、PPARD和PPARG激动剂对所选基因表达、细胞凋亡和细胞增殖的影响。添加CEM可刺激LE和ST细胞中该亚型的PPARA表达和DNA结合活性（P<0.05）。在ST细胞中检测到CEM存在时PPARD mRNA表达增加（P<0.05），而两种细胞类型中PPARG转录本的浓度均因CEM而降低（P<0.05）。猪子宫内膜的LE和ST细胞具有PPARA、PPARD和PPARG蛋白，细胞核染色明显，主要在ST细胞中可见。在LE细胞中，用15-脱氧-Δ12,14-前列腺素（PG）J2激活PPARG可下调编码氨基酸转运体1（SLC38A1）、白血病抑制因子（LIF）和参与PG合成的酶的基因表达（P<0.05）。在ST细胞中，使用的两种激动剂（L-165,041和cPGI2）激活PPARD亚型以及用15-脱氧-Δ12,14-PGJ2激活PPARG亚型均可增加血管内皮生长因子A（VEGFA）mRNA表达（P<0.05）。此外，GW9578（PPARA激动剂）和15-脱氧-Δ12,14-PGJ2可刺激ST细胞中葡萄糖转运体1（SLC2A1）基因表达。15-脱氧-Δ12,14-PGJ2在上调ST细胞中BAX/BCL2 mRNA表达比值和活性半胱天冬酶-3浓度方面也有效（P<0.05）。最后，GW9578刺激LE和ST细胞增殖，而罗格列酮（PPARG激动剂）增加了存活的ST细胞数量，但未增加LE细胞数量。总之，本研究表明孕体产物可差异调节猪子宫内膜中PPARs的表达和活性。PPARs的激活可能反过来影响该组织中的营养物质转运、PG合成、血管生成、细胞凋亡或细胞增殖。因此，PPAR亚型似乎在猪子宫的发育和功能中起重要作用。
