Effects of Infection with SARS-CoV-2 on the Male and Female Reproductive Systems: A Review.

Coronavirus Disease-2019 (COVID-19) is a rapidly spreading pandemic that began at the end of 2019. COVID-19 is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Reproductive health has always been one of the most important healthcare problems, and the impacts of COVID-19 on the reproductive systems have become an emerging topic. The effects of infection with SARS-CoV-2 on males are more harmful than on females. The outcomes of pregnancy also can show the condition of male and female reproductive system health. The vertical transmission of SARS-CoV-2 significantly affects pregnancy healthy. SARS-CoV-2, antibody, and other factors, such as the decline of lymphocyte counts, and increased erythrocyte sedimentation rate, C-reactive protein, and D-dimer levels, are evidence of SARS-CoV-2 vertical transmission. Angiotensin-converting enzyme 2 (ACE2) is regarded as a virus receptor in the reproductive system. The expression and activity of ACE2 are influenced by sex hormones, especially the male sex hormones. The strength of immunity is crucial to fighting off viral infection. Antibodies against SARS-CoV-2 show different expression in male and female patients, and the antibodies have been regarded as having potential applications in COVID-19 prevention and treatment. This review aims to present the current status of what is known about the involvement of the male and female reproductive systems, as well as the effects on pregnancy health, during infection with SARS-CoV-2, and discusses the implications for future fertility.

Associations Between Cytochrome P450 (CYP) Gene Single-Nucleotide Polymorphisms and Second-to-Fourth Digit Ratio in Chinese University Students.

BACKGROUND Cytochrome P450 (CYP) genes are necessary for the production or metabolism of fetal sex hormones during pregnancy. The second-to-fourth digit ratio (2D: 4D) is formed in the early stage of human fetal development and considered an indicator reflecting prenatal sex steroids levels. We explored the association between 2D: 4D and single-nucleotide polymorphisms (SNPs) of CYP. MATERIAL AND METHODS Correlation analysis between 2D: 4D and 8 SNPs, rs2687133 (CPY3A7), rs7173655 (CYP11A1), rs1004467, rs17115149, and rs2486758 (CYP17A1), and rs4646, rs2255192, rs4275794 (CYP19A1), was performed using data from 426 female and 412 male Chinese university students. SNP genotyping was conducted using PCR. Digit lengths were photographed and measured by image processing software. RESULTS rs2486758 (CYP17A1) correlated with left hand 2D: 4D in men (P=0.026), and rs1004467 (CYP17A1) correlated with right hand 2D: 4D in men (P=0.008) and the whole population (P=0.032). In men, allele G rs1004467 decreased right hand 2D: 4D, while allele C of rs2486758 increased left hand 2D: 4D. In women, left hand 2D: 4D was higher in genotypes with allele A of SNP rs4646 (CYP19A1) under the dominant genetic model; female DR-L was higher in genotypes with allele T of rs17115149 (CYP11A1). SNPs rs2687133 (CYP3A7) and rs1004467 (CYP17A1) were significantly correlated with right hand 2D: 4D (P=0.0107). CONCLUSIONS SNPs rs1004467 and rs2486758 of CYP17A1 are significant in the relationship between 2D: 4D and CYP gene polymorphisms under different conditions. SNP interactions between CYP genes probably impact 2D: 4D. The correlation between 2D: 4D and some sex hormone-related diseases may be due to the effect of CYP variants on the 2 phenotypes.

[Lycium barbarum polysaccharide reduces testicular spermatogenic injury in Immp2l－/－mice through GPX4 and AIF pathways].

OBJECTIVE: To investigate the protective effect of Lycium barbarum polysaccharide (LBP) against testicular spermatogenic injury in mice with oxidative stress (OS) and its mechanism. METHODS: A unique OS model was made in 1.5-month-old mice with mitochondrial inner membrane-like peptide-2 mutation (Immp2l－/－), which were fed with water (the negative control group) or LBP in water at the concentration of 20 mg/kg (the LBP intervention group), and wild-type Immp2l＋/＋ mice used as normal controls and fed with water only. Then all the mice were sacrificed at 13 months old and the testis tissue harvested for observation of pathological changes by HE staining, measurement of routine semen parameters, and detection of the apoptosis of spermatogenic cells by TUNEL and the expression levels of glutathione peroxidase 4 (GPX4) and apoptosis-inducing factor (AIF) by immunohistochemistry and Western blot. RESULTS: Thinned testicular cortex was observed in the negative controls, with evident vacuolar degeneration and reduced numbers of germ cells and elongated spermatids in the lumen of the seminiferous tubules, but all these pathological changes were improved and the germ cells at different levels orderly arranged in the LBP intervention group. Compared with the normal controls, the mice in the negative control group showed dramatically reduced sperm count (ï¼»72.89 ± 8.28ï¼½ vs ï¼»20.78 ± 1.45ï¼½ ×106, P<0.01) and the percentages of progressively motile sperm (PMS) (ï¼»58.62 ± 6.15ï¼½% vs ï¼»18.37 ± 2.67ï¼½%, P<0.01) and morphologically normal sperm (MNS) (ï¼»65.81 ± 7.69ï¼½% vs ï¼»20.33 ± 3.17ï¼½%, P<0.01) and increased apoptosis of spermatogenic cells (ï¼»1.45 ± 0.43ï¼½% vs ï¼»7.14 ± 0.78ï¼½%, P<0.01). LBP intervention, however, significantly increased the sperm count (ï¼»45.25 ± 3.39ï¼½ ×106, P<0.05), PMS (ï¼»36.34 ± 4.56ï¼½%, P<0.05) and MNS (ï¼»38.72 ± 3.63ï¼½%, P<0.05) and decreased the apoptosis of spermatogenic cells (ï¼»2.28 ± 0.07ï¼½%, P<0.01). The mice in the LBP intervention group, in comparison with the negative controls, exhibited remarkably up-regulated expression of GPX4 (2.75 ± 0.48 vs 1.43 ± 0.17, P<0.05) and down-regulated expression of AIF (2.43 ± 0.15 vs 1.35 ± 0.51, P<0.05). CONCLUSIONS: Lycium barbarum polysaccharide at 20 mg/kg can reduce testicular spermatogenic injury in Immp2l－/－ mice with oxidative stress through GPX4 and AIF pathways.

The Association of Partial Azoospermia Factor C Deletions and Male Infertility in Northwestern China.

BACKGROUND: Male infertility is a major health issue worldwide. Y chromosome microdeletions are well-characterized genetic causes of male infertility. The association of partial AZFc deletions (gr/gr, b2/b3, and b1/b3) with male infertility is not well confirmed in diverse populations. The purpose of the present study was to investigate the frequency of partial AZFc deletions and their association with male infertility in a population from Northwestern China. METHODS: Multiplex polymerase chain reaction was used to detect partial AZFc deletions in 228 infertile patients. We analyzed 141 cases of azoospermia (AS), 87 cases of oligozoospermia (OS), and 200 fertile controls. RESULTS: Our data showed that the frequency of a b2/b3 deletion in infertile men, men with AS, men with OS, and controls was 3.51, 2.13, 5.75, and 0.00%, respectively. The frequency of this deletion was significantly different between the infertile group and the control group (3.51 vs. 0.00%, respectively, p = 0.021) and between the OS group and the control group (5.75 vs. 0.00%, respectively, p = 0.003). The frequency of a gr/gr deletion in each group was 11.84, 9.22, 16.09, and 7.50%, respectively. The frequency of a gr/gr deletion was significantly different between the OS group and the control group (16.09 vs. 7.50%, respectively, p = 0.026) but not between the infertile group and the control group (11.84 vs. 7.50%, p = 0.132) or the AS group and the control group (9.22 vs. 7.50%, p = 0.569). The frequency of a b1/b3 deletion was 0.44, 0.71, 0.00, and 3.00%, respectively. For this deletion, there was no significant difference between the infertile (0.44 vs. 3.00%, p = 0.089), AS (0.71 vs. 3.00%, p = 0.276), and OS groups (0.00 vs. 3.00%, p = 0.236) and the control group. CONCLUSIONS: Our results suggest that the b2/b3 deletion might be associated with male infertility and that the gr/gr deletion might be associated with spermatogenic failure in men with OS in Northwestern China (Ningxia).

The association of four SNPs in DNA mismatch repair genes with idiopathic male infertility in northwest China.

DNA mismatch repair (MMR) plays a critical role in the maintenance of genetic integrity. The failure of MMR in sperm DNA was found in male infertility. However, its aetiology in idiopathic male infertility (IMI) remains unknown. The present study was to investigate whether the four SNPs (rs26279 in MSH3, rs1800734 and rs4647269 in MLH1 and rs175080 in MLH3) in MMR genes were associated with IMI or not. The interactions of the SNPs were also performed to clarify its genetic aetiology. In the present study, 209 clinically diagnosed IMI men and 201 fertile men were recruited. Four SNPs were genotyped by DNA sequencing. It was the first time to investigate the association between rs26279 in MSH3 and IMI. The genotype frequency distribution of rs26279 (A>G) in MSH3 was found to be significantly different between IMI and control (p < 0.05), as well as azoospermia. The rs1800734 and rs4647269 in MLH1 were found to be significantly different between severe oligozoospermia and control groups (p < 0.05). However, rs175080 in MLH3 was not significantly different between IMI and control (p > 0.05). Multifactor dimensionality reduction (MDR) for detecting interactions showed that there were no interactions among the four SNPs on IMI.

Luteinizing Hormone Receptor Mutation (LHRN316S) Causes Abnormal Follicular Development Revealed by Follicle Single-Cell Analysis and CRISPR/Cas9.

Abnormal interaction between granulosa cells and oocytes causes disordered development of ovarian follicles. However, the interactions between oocytes and cumulus granulosa cells (CGs), oocytes and mural granulosa cells (MGs), and CGs and MGs remain to be fully explored. Using single-cell RNA-sequencing (scRNA-seq), we determined the transcriptional profiles of oocytes, CGs and MGs in antral follicles. Analysis of scRNA-seq data revealed that CGs may regulate follicular development through the BMP15-KITL-KIT-PI3K-ARF6 pathway with elevated expression of luteinizing hormone receptor (LHR). Because internalization of the LHR is regulated by Arf6, we constructed LHRN316S mice by CRISPR/Cas9 to further explore mechanisms of follicular development and novel treatment strategies for female infertility. Ovaries of LHRN316S mice exhibited reduced numbers of corpora lutea and ovulation. The LHRN316S mice had a reduced rate of oocyte maturation in vitro and decreased serum progesterone levels. Mating LHRN316S female mice with ICR wild type male mice revealed that the infertility rate of LHRN316S mice was 21.4% (3/14). Litter sizes from LHRN316S mice were smaller than those from control wild type female mice. The oocytes from LHRN316S mice had an increased rate of maturation in vitro after progesterone administration in vitro. Furthermore, progesterone treated LHRN316S mice produced offspring numbers per litter equivalent to WT mice. These findings provide key insights into cellular interactions in ovarian follicles and provide important clues for infertility treatment.

Engineering Female Germline Stem Cells with Exocytotic Polymer Dots.

Germline stem cells (GSCs) are the only cell population capable of passing genetic information to offspring, making them attractive targets in reproductive biology and fertility research. However, it is generally more difficult to introduce exogenous biomolecules into GSCs than other cell types, impeding the exploration and manipulation of these cells for biomedical purposes. Herein, semiconductor polymer dots (Pdots)-based nanocomplex Pdot-siRNA is developed and achieves effective knockdown of target genes in female germline stem cells (FGSCs). Advantage of high fluorescence brightness of Pdots is taken for comprehensive investigation of their cellular uptake, intracellular trafficking, and exocytosis in FGSCs. Importantly, Pdots show excellent biocompatibility and minimally disturb the differentiation of FGSCs. Intracellular Pdots escape from the lysosomes and undergo active exocytosis, which makes them ideal nanocarriers for bioactive cargos. Moreover, Pdot-siRNA can penetrate into 3D ovarian organoids derived from FGSCs and down-regulate the expression levels of target genes. This study investigates the interface between a type of theranostic nanoparticles and FGSCs for the first time and sheds light on the manipulation and medical application of FGSCs.

Serum- and Feeder-Free Culture of Juvenile Monkey Female Germline Stem Cells and Testosterone Regulation of their Self-Renewal.

Female germline stem cells (FGSCs) have been found in mouse, rat, pig, sheep and human ovaries. However, there is no information on the isolation or long-term culture of FGSCs from non-human primates. Here, we identified the presence of FGSCs in the ovaries of juvenile (3-4-year-old) cynomolgus monkeys using DDX4 and Ki67 double immunofluorescence. Then, a long-term serum- and cell feeder-free culture system for these FGSCs was used to establish a cell line, and its biological characteristics were analyzed. We found that testosterone promoted self-renewal of the cells. This study confirmed for the first time the presence of FGSCs in the ovary of non-human primates. This culture system and cell line will be of great significance for research in medicine and reproductive biology.