Molecular characterization of follicle stimulating hormone receptor (FSHR) gene in the Indian river buffalo (Bubalus bubalis)

Effect of heat exposure on prostaglandin production and expression of COX-2, PGES, PGFS, ITGAV and LGALS15 mRNAs in endometrial epithelial cells of buffalo (Bubalus bubalis)

BACKGROUND

Early embryonic mortality is one of the major intriguing factors of reproductive failure that causes considerable challenge to the mammalian cell biologists. Heat stress is the major factor responsible for reduced fertility in farm animals. The present study aimed to investigate the influence of heat stress on prostaglandin production and the expression of key genes, including COX-2, PGES, PGFS, ITGAV and LGALS15, in buffalo endometrial epithelial cells.

METHODS AND RESULTS

Buffalo genitalia containing ovaries with corpus luteum (CL) were collected immediately post-slaughter. The stages of the estrous cycle were determined based on macroscopic observations of the ovaries. Uterine lumens of the mid-luteal phase (days 6-10 of the estrous cycle) were washed and treated with trypsin to isolate epithelial cells, which were then cultured at control temperature (38.5 °C for 24 h) or exposed to elevated temperatures [38.5 °C for 6 h, 40.5 °C for 18 h; Heat Stressed (HS)]. The supernatant and endometrial epithelial cells were collected at various time points (0, 3, 6, 12, and 24 h) from both the control and treatment groups. Although heat stress (40.5 °C) significantly (P < 0.05) increased COX-2, PGES, and PGFS transcripts in epithelial cells but it did not affect the in vitro production of PGF2α and PGE2. The expression of ITGAV and LGALS15 mRNAs in endometrial epithelial cells remained unaltered under elevated temperature conditions.

CONCLUSION

It can be concluded that elevated temperature did not directly modulate prostaglandin production but, it promoted the expression of COX-2, PGES and PGFS mRNA in buffalo endometrial epithelial cells.

Cilia, Centrosomes and Skeletal Muscle

Primary cilia are non-motile, cell cycle-associated organelles that can be found on most vertebrate cell types. Comprised of microtubule bundles organised into an axoneme and anchored by a mature centriole or basal body, primary cilia are dynamic signalling platforms that are intimately involved in cellular responses to their extracellular milieu. Defects in ciliogenesis or dysfunction in cilia signalling underlie a host of developmental disorders collectively referred to as ciliopathies, reinforcing important roles for cilia in human health. Whilst primary cilia have long been recognised to be present in striated muscle, their role in muscle is not well understood. However, recent studies indicate important contributions, particularly in skeletal muscle, that have to date remained underappreciated. Here, we explore recent revelations that the sensory and signalling functions of cilia on muscle progenitors regulate cell cycle progression, trigger differentiation and maintain a commitment to myogenesis. Cilia disassembly is initiated during myoblast fusion. However, the remnants of primary cilia persist in multi-nucleated myotubes, and we discuss their potential role in late-stage differentiation and myofiber formation. Reciprocal interactions between cilia and the extracellular matrix (ECM) microenvironment described for other tissues may also inform on parallel interactions in skeletal muscle. We also discuss emerging evidence that cilia on fibroblasts/fibro-adipogenic progenitors and myofibroblasts may influence cell fate in both a cell autonomous and non-autonomous manner with critical consequences for skeletal muscle ageing and repair in response to injury and disease. This review addresses the enigmatic but emerging role of primary cilia in satellite cells in myoblasts and myofibers during myogenesis, as well as the wider tissue microenvironment required for skeletal muscle formation and homeostasis.

Cloning and expression analysis of the follicle-stimulating hormone receptor (FSHR) gene in the reproductive axis of female yaks (Bos grunniens)

Follicle-stimulating hormone receptor (FSHR) plays a central role in promoting follicle maturation through the follicle-stimulating hormone (FSH)-mediated cAMP pathway in animals. The objectives of the present study were to clone the FSHR gene of yaks (Bos grunniens) and compare differences in FSHR mRNA expression in the reproductive axis between yaks and cattle. Hypothalamus, anterior pituitary, oviduct, ovary, and uterus tissue samples were collected from adult female yaks (n = 5) and cattle (n = 5) during the follicular phase. Using reverse transcriptase-polymerase chain reaction (RT-PCR), we found that the FSHR coding region of the yak is 2088 bp and encodes 695 amino acids. Its amino acid sequence showed 99.38%-72.22% similarity to the homologous genes of cattle, goats, sheep, cats, donkeys, horses, humans, chickens, monkeys, mice, rats, and wild boar. Real-time PCR analysis revealed that the FSHR gene was expressed in all tissues examined. Expression of the FSHR gene in the yak was higher in the uterus than other tissues (P < 0.05) but, in cattle, was higher in the ovary than other tissues (P < 0.05). The FSHR gene expression level in the cattle ovary was significantly higher than that in the yak ovary (P < 0.01). These results indicate that the FSHR gene is relatively conserved in the course of animal evolution. The variation in sequence and expression level of FSHR between the two species might be associated with the difference in their reproduction.

MiR-31 and miR-143 affect steroid hormone synthesis and inhibit cell apoptosis in bovine granulosa cells through FSHR

The regulatory role of microRNAs (miRNAs) has been explored in ovarian cells, and the effects of miRNAs on gonadal development, apoptosis, ovulation, and steroid production have been reported. In this study, we analyzed the effects of follicle stimulating hormone (FSH) on miR-31 and miR-143 expression levels in bovine granulosa cells (GCs). Our results demonstrated that the FSH receptor (FSHR) is a common target gene of miR-31 and miR-143 in bovine GCs. We further analyzed the roles of miR-31 and miR-143 in bovine GCs by transfecting miR-31 and miR-143 mimics and inhibitors. The Western blot and RT-PCR results showed that miR-31 and miR-143 reduced the mRNA and protein expression levels of FSHR. Moreover, miR-31 overexpression decreased the secretion of progesterone (P4), and miR-143 overexpression decreased both the synthesis of P4 and the secretion of estrogen (E2). In contrast, miR-31 inhibition increased the secretion of progesterone (P4), and miR-143 inhibition increased both the synthesis of P4 and the secretion of E2. Finally, we analyzed the possible effects of miR-31 and miR-143 on bovine GC apoptosis. The results showed that transfection with miR-31 and miR-143 mimics promoted GC apoptosis and that miR-143 and miR-31 inhibition reduced the rate of apoptosis in bovine GCs. Taken together, our results indicate that miR-31 and miR-143 decrease steroid hormone synthesis and inhibit bovine GC apoptosis by targeting FSHR.

Effects of growth differentiation factor-9 and FSH on in vitro development, viability and mRNA expression in bovine preantral follicles

The present study investigated the role of growth differentiation factor (GDF)-9 and FSH, alone or in combination, on the growth, viability and mRNA expression of FSH receptor, proliferating cell nuclear antigen (PCNA) and proteoglycan-related factors (i.e. hyaluronan synthase (HAS) 1, HAS2, versican, perlecan) in bovine secondary follicles before and after in vitro culture. After 12 days culture, sequential FSH (100 ng mL–1 from Days 0 to 6 and 500 ng mL–1 from Days 7 to 12) increased follicular diameter and resulted in increased antrum formation (P < 0.05). Alone, 200 ng mL–1 GDF-9 significantly reduced HAS1 mRNA levels, but increased versican and perlecan mRNA levels in whole follicles, which included the oocyte, theca and granulosa cells. Together, FSH and GDF-9 increased HAS2 and versican (VCAN) mRNA levels, but decreased PCNA mRNA expression, compared with levels in follicles cultured in α-minimum essential medium supplemented with 3.0 mg mL–1 bovine serum albumin, 10 µg mL–1 insulin, 5.5 µg mL–1 transferrin, 5 ng mL–1 selenium, 2 mM glutamine, 2 mM hypoxanthine and 50 μg mL–1 ascorbic acid (α-MEM+). Comparisons of uncultured (0.2 mm) and α-MEM+ cultured follicles revealed that HAS1 mRNA expression was higher, whereas VCAN expression was lower, in cultured follicles (P < 0.05). Expression of HAS1, VCAN and perlecan (HSPG2) was higher in cultured than in vivo-grown (0.3 mm) follicles. In conclusion, FSH and/or GDF-9 promote follicular growth and antrum formation. Moreover, GDF-9 stimulates expression of versican and perlecan and interacts positively with FSH to increase HAS2 expression.

Evaluating the role of the FSH receptor gene Thr307-Ala and Asn680-Ser polymorphisms in male infertility and their association with semen quality and reproductive hormones

OBJECTIVE

To determine whether Thr(307)-Asn(680) and Ala(307)-Ser(680) polymorphisms of the follicle-stimulating hormone receptor (FSH-R) gene are associated with male infertility, semen quality, and reproductive hormones.

PATIENTS AND METHODS

The FSH-R polymorphisms at codons 680 and 307 were analysed by restriction-fragment-length polymorphism (RFLP) in 172 infertile men and in an equal number of age-matched healthy fertile men. Genotyping of the FSH-R gene was performed using the polymerase chain reaction RFLP technique. All of the participants underwent semen analysis, and reproductive hormones were also measured.

RESULTS

Allelic frequencies were 29.7% serine (Ser) and 70.3% asparagine (Asn) for fertile men (the control group), and 33.1% Ser and 66.9% Asn for infertile men (P > 0.05). The FSH-R genotype at position 680 was 49.4% (Asn/Asn), 41.9% (Asn/Ser), and 8.7% (Ser/Ser) in the control group and 40.1% (Asn/Asn), 46.5% (Asn/Ser), and 13.4% (Ser/Ser) in infertile men, respectively (P > 0.05, chi-squared test). Allelic frequencies were 33.1% alanine (Ala) and 66.9% threonine (Thr) for the control group, and 37.8% Ala and 62.2% Thr for the infertile men. The frequencies of genotypes at position 307 were 45.5% Thr/Thr, 43% Thr/Ala, and 11.6% Ala/Ala for the control group and 36.1% Thr/Thr, 52.3% Thr/Ala, and 11.6% Ala/Ala for infertile men. No significant association between codon 680 and codon 307 genotypes and infertility was observed (P = 0.076 and P = 0.073, respectively). The odds ratio (OR) values indicated that individuals with the Thr/Thr + Asn/Ser combined genotypes had a > 50% decreased risk for developing infertility (OR = 0.44; 95% confidence interval [CI]: 0.22-0.77; P = 0.006). The patients with heterozygous Thr/Ala + Asn/Ser combined genotype were 2.65 times more susceptible to infertility than the control group (OR = 2.65; 95% CI: 1.74-3.82; P = 0.0053). The FSH-R codon 680 and codon 307 genotypes did not result in different serum FSH levels either in men with normal spermatogenesis (the control group) or in men with oligoasthenoteratozoospermia (infertile men). We did not observe any significant association of FSH-R genotype frequencies with any of the sperm characteristics analysed in either group.

CONCLUSIONS

No significant correlation between serum FSH levels and semen characteristics, or fertility status and FSH-R gene polymorphisms was found. The combination of heterozygous Thr/Ala + Asn/Ser genotypes increases the risk for male infertility.