Association of gene polymorphisms of estrogen receptor, follicle-stimulating hormone β and leptin with follicular cysts in Large White sows

Alterations of Cortisol and Melatonin Production by the Theca Interna Cells of Porcine Cystic Ovarian Follicles

Simple Summary

The mechanism of follicular cyst formation is largely unknown but changes in follicular composition are known to be involved. In particular, there is abnormal hormone secretion in cystic follicles. Here, we found there was disruption of hormone secretion in the fluid of cystic follicles in sows. The glucocorticoid receptor was highly expressed, and the melatonin receptor was weakly expressed in cystic follicles compared with control follicles. Thus, secretion of steroid hormones in cystic follicles is disrupted and disturbances in signaling via cortisol and melatonin are involved in the development of follicular cysts in sows.

Abstract

(1) Background: Cortisol and melatonin (MT) act in regulating follicular development. We hypothesized that abnormal levels of cortisol, MT, and steroids in theca interna cells might be involved in the development of follicular cysts in sows. (2) Methods: To test this hypothesis, we measured the mRNA levels of enzymes involved in steroid hormone synthesis, the glucocorticoid receptor (GR), and melatonin receptors (MTRs) in theca interna cells of cystic and normal porcine follicles. (3) Results: The concentrations of estradiol, progesterone, and cortisol were greater in cystic follicles than in control ones (p = 0.034, p = 0.020, p = 0.000), but the concentration of MT was significantly lower (p = 0.045). The levels of GR, 11β-HSD1, and 11β-HSD2 were higher in cystic follicles than in control l follicles. MT types 1 and 2 were significantly lower in cystic follicles (p < 0.05). The mRNA expression levels of genes encoding the steroid hormone synthesis enzymes, steroidogenic acute regulatory protein (StAR), recombinant cytochrome P45011A1 (CYP11A1), and 3β-hydroxysteroid dehydrogenase (3β-HSD) in theca interna cells of cystic follicles were significantly higher than in control follicles. Thus, there was disruption of hormone secretion in the fluid of cystic follicles in sows. (4) Conclusions: The levels of steroid hormones, cortisol and MT are disrupted in porcine cystic follicles.

Morphological changes in mouse ovary due to hormonal hypersecretion and matrix metalloproteinase -2 activity

We analyzed whether aberrant gonadotropin secretion affects the morphological remodeling of murine ovarian tissues facilitated by activated matrix metalloproteinase (MMP) enzymes. Six mice were intraperitoneally injected with 5 IU of pregnant mare serum gonadotropin (PMSG) or human chorionic gonadotropin (HCG) every two days after estrus synchronization. Morphology and expression of various MMPs were assessed following the successful induction of hormonal secretion in these tissues. HCG treatment, but not PMSG treatment, resulted in the expanded production of granulose second follicular cells. In addition, the number of developing follicular cells in the HCG group increased compared with that in the PMSG group. Ovarian diameters were also very small in the PMSG group. Immunohistochemistry revealed decreased MMP-2 protein activity in the HCG group and increased MMP-2 activity in the PMSG group. Activity was particularly high in theca and granulose cells of the PMSG group, but only partial activity was observed in the theca cells of the HCG group. Vascular endothelial growth factor activity was increased in both the external and internal theca cell walls in the PMSG group while the HCG group showed high overall expression of this protein in the internal theca cells. These data indicate that follicular cell activity and remodeling of the ovaries differ based on the type of secretory hormone signals they receive. Inappropriate gonadotropin secretion may induce functional changes in the ovaries, and follicular remodeling may be facilitated by the activity of various MMPs.

Association of RBP-4 gene polymorphisms with follicular cysts in large white sows

Follicular cysts, which is a common infertility disease, can cause financial losses in pig breeding programmes. The pathogenesis and mechanisms of the formation of follicular cysts are not understood clearly. In our previous study, the concentration of retinol-binding protein 4 (RBP-4) in the follicular fluid (FF) of the ovary with follicular cysts was found to be significantly higher than that of normal ovary, thereby suggesting that RBP-4 may be a candidate biomarker for porcine follicular cysts. To study the association of RBP-4 and follicular cysts further, we detected the polymorphisms of the RBP-4 gene and the presence of follicular cysts by PCR-Restriction fragment length polymorphism (RFLP) assay. In this study, we screened the mutations of RBP-4 gene in 79 sows with follicular cysts and 100 normal sows without cysts. Results showed that +249-63G>C polymorphisms were significantly associated with follicular cysts, and sows with CC genotype in RBP-4 gene had a high risk of developing follicular cysts. Hence, our findings further proved that RBP-4 may be a novel biomarker for follicular cysts, which may be valuable for the diagnosis of follicular cysts and molecular breeding of pigs.

Protective effect of oestrogen receptor α-PvuII transition against idiopathic male infertility: a case-control study and meta-analysis

RESEARCH QUESTION

Is there any genetic association between oestrogen receptor alpha [ERα]-PvuII polymorphism and idiopathic male infertility?

DESIGN

A total of 226 infertile and 213 fertile men participated in the present case-control study. ERα-PvuII genotyping was performed using the polymerase chain reaction-restriction fragment length polymorphism [PCR-RFLP] method. Meta-analysis was also performed by pooling data collected from seven other eligible studies identified by searches of PubMed, Embase, Google Scholar, and Science Direct databases. Summary odds ratios were estimated by fixed- or random-effects models. The molecular effects of ERα-PvuII polymorphism were evaluated by bioinformatics tools.

RESULTS

A significant protective association was reported between ERα-PvuII and male infertility in the homozygote model [OR=0.54, 95%CI=0.3-0.98, p=0.042]. Also, a similar association was observed in asthenozoospermia subgroup [OR=0.4, 95%CI=0.18-0.9, p=0.025]. Meta-analysis also revealed that the ER-PvuII polymorphism was significantly associated with the decreased risk of male infertility in the heterozygote co-dominant model [OR=0.80, 95%CI=0.64-0.99, p=0.042]. Moreover, similar protective results were reported in stratified analyses in Caucasian subgroup in the dominant genetic model [OR=0.66, 95%CI=0.45-0.96, p=0.029] and in the heterozygote co-dominant model [OR=0.62, 95%CI=0.41-0.93, p=0.021]. A significant association was also found in studies with sample size of less than 400 subjects in heterozygote co-dominant model [OR=0.69, 95%CI=0.50-0.95, p=0.023]. The bioinformatics data indicated that ER-PvuII polymorphism could significantly affect RNA structure of ERα [p=0.004].

CONCLUSION

The ERα-PvuII polymorphism could be considered as a possible protective factor against male infertility.

Genetic effect and combined genotype effect of ESR, FSHβ, CTNNAL1 and miR-27a loci on litter size in a Large White population

To select new Large White line with high number of piglets born, genotypes of estrogen receptor (ESR), the follicle stimulating hormone β subunit (FSHβ), catenin alpha like 1 (CTNNAL1) and miR-27a were tested in 472 Large White sows. The associations of different genotypes with litter size traits were also studied. The results showed ESR^BB and FSHβ^BB sows produced 0.41-1.49 more pigs per litter (p < .05) for total number born (TNB) and number born alive (NBA) than did other corresponding genotypes. TNB of CTNNAL1^CG sows is 0.50 more pigs per litter (p < .05) than that of CTNNAL1^GG sows with the dominance effect of 0.25 pigs per litter (p < .05). miR-27a^BB sows had a less estimated breeding value (EBV) to TNB and had a more number of mummified pigs (NM) than did miR-27a^AA or miR-27a^AB sows (p < .05). Therefore, ESR^B, FSHβ^B, CTNNAL1^G, miR-27a^A allele was favorable for litter size traits. Furthermore, combined genetic effect analysis showed ESR^AAFSHβ^BB, ESR^AACTNNAL1^CG, ESR^AAmiR-27a^AA, FSHβ^BBCTNNAL1^CC, FSHβ^BBmiR-27a^AA and CTNNAL1^CG miR-27a^AB was the favorable combined genotype for litter size traits. These results identified favorable alleles and genotypes for litter size traits and suggested a potential selection scheme for litter size in Large White pigs.