Estradiol-17ß regulates proliferation and apoptosis of sheep endometrial epithelial cells by regulating the relative abundance of YAP1.

Yes-associated protein 1 (YAP1) transcription regulator of the Hippo protein kinase pathway, serves as a key regulator of tissue growth and organ size by regulating cell proliferation and apoptosis. Effects of YAP1 on proliferation and apoptosis of sheep endometrial epithelial cells (EEC) as a result of estradiol-17ß (E2) treatment, however, remain unclear. In the present study, the abundance of YAP1 protein in the uterine horn was greater than that in the uterine body or cervix. The YAP1 protein was primarily localized in the endometrial luminal and glandular epithelial cells of the uterine horn of ewes on day 2 of the estrous cycle. Compared with control samples, there was a lesser abundance of YAP1 mRNA transcript that was associated with a lesser proliferation and greater apoptosis of EEC. There were also lesser concentrations of epidermal growth factor and insulin-like growth factor 1 in the spent culture medium when there was a lesser abundance of YAP1 mRNA in EEC compared with those in the control group. When there was a greater abundance of YAP1 mRNA transcript, there were greater concentrations of epidermal growth factor and insulin-like growth factor 1 in the spent media. Furthermore, with estradiol-17ß treatment the abundance of YAP1 mRNA transcript was similar to that of the control samples. Taken together, estradiol-17ß may function as an essential regulator of EEC proliferation and apoptosis by modulation of concentrations of YAP1 protein in the sheep uterus. These results indicate there are molecular mechanisms of estradiol-17ß and YAP1 in EEC proliferation and apoptosis of ewes.

Effect of PPARGC1A on the development and metabolism of early rabbit embryos in vitro.

Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PPARGC1A) is a central regulator of mitochondrial biogenesis and metabolism, and its expression is closely related to embryo development. To gain insights into the possible mechanisms of PPARGC1A during early embryogenesis, the development potential, mitochondrial biogenesis, and the culture medium metabolomics of embryos were evaluated when PPARGC1A overexpressed or suppressed in rabbit zygotes. Results showed that different PPARGC1A levels in rabbit zygotes could affect blastocyst percentage, and the expressions of mitochondrial biogenesis and metabolic-related genes, as well as the glutathione and adenosine triphosphate levels during early embryo development. In addition, compared with the controls, 12 and 10 different metabolites involved in carbohydrate, amino acid, and fatty acid metabolism were screened in the 5 day's spent culture medium of PPARGC1A overexpressed and suppressed embryos by gas chromatography-mass spectrometer, respectively. Consistent with these metabolite changes, the transcriptions of genes encoding glucose transporters and fatty acid biosynthetic proteins in the embryos from different groups were regulated by PPARGC1A during rabbit embryo development. Taken together, these data provide evidence that PPARGC1A may regulate early rabbit embryo development through mitochondrial biogenesis and metabolism.

Suppression of miR-1197-3p attenuates H2O2-induced apoptosis of goat luteinized granulosa cells via targeting PPARGC1A.

Peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PPARGC1A) acts as a powerful coactivator of many transcriptional factors that relate to granulosa cell (GC) apoptosis. In this study, the miRNAs mediating goat follicular atresia and luteinized granulosa cell (LGC) apoptosis induced by hydrogen peroxide (H2O2) via PPARGC1A were investigated. Our results showed that miR-1197-3p targeted PPARGC1A was predicted by bioinformatics algorithm and verified by luciferase reporter assay. In addition, miR-1197-3p promoted goat LGC apoptosis via PPARGC1A through mitochondrial-dependent apoptosis pathway, and these effects could be restored by PPARGC1A overexpression. Moreover, H2O2-induced LGC apoptosis significantly upregulated miR-1197-3p expression and downregulated PPARGC1A level. Pretreatment of miR-1197-3p inhibitor alleviated LGC apoptosis induced by 400 µM H2O2 for 12 h, and preserved the mitochondrial membrane potential by increasing PPARGC1A expression. In conclusion, miR-1197-3p might act as an essential regulator of goat LGC apoptosis potentially via the mitochondrial-dependent apoptosis pathway by targeting PPARGC1A.

Expression of Hippo signaling pathway components in Hu sheep male reproductive tract and spermatozoa.

Hippo signaling pathway is essential for tissue development and homeostasis, while its specific role in male reproductive tract development is still unclear. The objective of this study is to elucidate the localization and expressions of key Hippo pathway components (MST1/2, LATS1/2 and YAP1) in male reproductive tract (testis, epididymis, and ductus deferens) of prepubertal (3-month-old) and postpubertal (9-month-old) Hu sheep, as well as in the cauda epididymal and ejaculated spermatozoa. Results showed that the Hippo pathway proteins were diversely localized in male reproductive tract portions, and most of their expression levels increased during sheep testicular maturation. In addition, these Hippo components were mainly localized and highly expressed in ejaculated spermatozoa compared with cauda epididymal spermatozoa. In ejaculated spermatozoa, LATS1 was localized in the acrosomal head region, and LATS2 and YAP1 were expressed in the midpiece part. Taken together, the presence of Hippo signaling cascade in the pubertal development of male reproductive tract and spermatogenesis of Hu sheep, provides new insights on the function of these components in the process of male sexual maturation, capacitation and fertilization.

Molecular cloning and expression of 17ß-hydroxysteroid dehydrogenase type 2 gene in Hu sheep.

17ß-Hydroxysteroid dehydrogenase type 2 (17ß-HSD2) catalyzes the NADP+-dependent oxidation of the most potent estrogen 17ß-estradiol into the weak estrogen estrone, and the conversion of testosterone to androstenedione. It has been reported that 17ß-HSD2 was expressed in many tissues in human, rats, however, the full-length sequence of 17ß-HSD2 gene and its expression in ewe were still unknown. In this study, we cloned the full-length cDNA sequence and investigated mRNA differential expression in 28 tissues of 12 adult Hu-Sheep which were fed with high- and low- dietary intake. The 1,317 bp full-length cDNA sequence was first cloned. The coding region was 1,167 bp in length, and the monomer was estimated to contain 389 amino acid residues. It shares high AA sequence identity with that of bos Taurus (96.13 %), sus scrofa (77.06 %), canis lupus familiaris (70.44 %), Callithrix jacchus (65.72 %), Nomascus leucogenys (65.46 %), pan troglodytes (65.21 %), human (64.69 %), mus musculus (58.35 %), and a comparatively lower identity to danio rerio (37.85 %). 17ß-HSD2 gene was high expressed in gastrointestinal (GI) tract, liver, but weakly expressed in other tissues. No detected expression was examined in lung. 17ß-HSD2 gene expression was significantly difference in rumen, omasum, duodenum, cecum, hypophysis after high- and low- dietary intake. Results from the present study suggested that 17ß-HSD2 plays a crucial role in almost all tissues protecting against excessive levels of active steroid hormone, and GI tract maybe an important steroid hormone metabolizing organ in Hu-Sheep. This present study is the first to provide the primary foundation for further insight into this ovine gene.