Long noncoding RNAs regulated spermatogenesis in varicocele-induced spermatogenic dysfunction

Neonatal vitamin A supplementation improves sheep fertility potential

This study aimed to explore the effects of neonatal vitamin A (VA) supplementation on testis development and spermatogenesis. A total of 32 newborn lambs were intramuscularly injected with corn oil (control group) or corn oil + 2500 IU/kg BW VA (VA group). They were slaughtered and sampled at 3 weeks and 8 months of age to analyze spermatogenesis, cell proliferation, hormone secretion, antioxidant status of the testis, and adult sheep sperm parameters. Compared with the control group, the expression of spermatogonial differentiation-related genes in VA group was up-regulated (P < 0.05). Testis weight, seminiferous tubule diameter, number of spermatogonium and spermatocyte, and sperm density increased significantly in VA group at 8 months of age (P < 0.05). Neonatal VA injection upregulated the expression of the cell proliferation marker PCNA and cell cycle-related genes in the testis (P < 0.05). VA increased the concentrations of testosterone (T), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) in the serum and upregulated steroidogenesis-related genes in the testis (P < 0.05). The antioxidant levels in the VA group were maintained at high levels. The total antioxidant capacity (T-AOC), antioxidant enzyme content and antioxidant-related genes were increased in the testis (P < 0.05). Furthermore, neonatal VA injection activated retinoic acid (RA) signaling to maintain the blood-testosterone barrier (BTB) in the testis of 3-week-old sheep. AMP-activated protein kinase (AMPK) and protein kinase B (AKT) signaling were also modulated in the sheep testis (P < 0.05). Taken together, VA supplementation in newborn rams promotes testis development and spermatogenesis to improve fertility.

Impacts of non-coding RNAs in the pathogenesis of varicocele

Two classes of non-coding RNAs, namely lncRNAs and miRNAs have been reported to be involved in the pathogenesis of varicocele. MIR210HG, MLLT4-AS1, gadd7, and SLC7A11-AS1 are among lncRNAs whose expression has been changed in patients with varicocele in association with the sperm quality. Animal studies have also suggested contribution of NONRATG001060, NONRATG002949, NONRATG013271, NONRATG027523 and NONRATG023747 lncRNAs in this pathology. Meanwhile, expression of some miRNAs, such as miR-210-3p, miR-21, miR-34a, miR-122a, miR-181a, miR-34c and miR-192a has been altered in this condition. Some of these transcripts have the potential to predict the sperm quality. We summarize the impacts of lncRNAs and miRNAs in the pathogenesis of varicocele.

Is Parthanatos Involved in Varicocele?

Varicoceles (VCs) have received widespread attention as a primary factor affecting male fertility and a pathological condition that may lead to decreased sperm count and motility in patients. Many studies have shown that an imbalance of local antioxidant balance exists in patients with VC, leading to an obvious increase in the content of reactive oxygen species (ROS) and may cause reductive stress. Excessive ROS may aggravate spermatogenesis dysfunction and affect male fertility. Poly(ADP-ribose) polymerase (PARP) is an enzyme associated with DNA repair in eukaryotic cells, can be activated by DNA fragments with structural damage, and has been considered a DNA damage receptor in DNA damage repair and apoptosis. We built a rat model of VC and an oxidative damage model of a spermatocyte-derived cell line (GC-2 cells) induced by hydrogen peroxide to study the role of PARP1 in VC. Differentially expressed genes (DEGs) were obtained by RNA sequencing in the testes of VC rats. Analysis of DEGs revealed some genes with significantly altered expression, which were validated in rat and cell models. Immunofluorescence, real-time quantitative PCR analysis, Western blot, and flow cytometry were used to analyze the changes between the control group and the VC or hydrogen peroxide group. Overall, we found that PARP1 protein expression increased in VC rats and in the hydrogen peroxide-induced oxidative stress model of GC-2 cells. Parthanatos may be one of the factors leading to reduced reproductive capacity in VC patients. Our study provides novel insights into the mechanisms of male infertility induced by oxidative stress and provides a new therapeutic target for VC.

Transcriptome sequencing reveals differences between leydig cells and sertoli cells of yak

In this study, we detected the expression of mRNAs, lncRNAs, and miRNAs in primary cultured leydig cells (LCs) and sertoli cells (SCs) of yak by RNA sequencing technology. A total of 84 differently expression mRNAs (DEmRNAs) (LCs vs. SCs: 15 up and 69 down), 172 differently expression lncRNAs (DElncRNAs) (LCs vs. SCs: 36 up and 136 down), and 90 differently expression miRNAs (DEmiRNAs) (LCs vs. SCs: 72 up and 18 down) were obtained between the two types of cells. GO enrichment and KEGG analysis indicated that the differential expression genes (DEGs) were more enriched in the regulation of actin cytoskeleton, Rap1/MAPK signaling pathway, steroid biosynthesis, focal adhesion, and pathways associated with metabolism. Targeted regulation relationship pairs of 3β-HSD and MSTRG.54630.1, CNTLN and MSTRG.19058.1, BRCA2 and MSTRG.28299.4, CA2 and novel-miR-148, and ceRNA network of LAMC3-MSTRG.68870.1- bta-miR-7862/novel-miR-151/novel-miR-148 were constructed by Cytoscape software. In conclusion, the differences between LCs and SCs were mainly reflected in steroid hormone synthesis, cell proliferation and metabolism, and blood-testicular barrier (BTB) dynamic regulation, and 3β-HSD, CNTLN, BRCA2, CA2, and LAMC3 may be the key factors causing these differences, which may be regulated by ncRNAs. This study provides a basic direction for exploring the differential regulation of LCs and SCs by ncRNAs.

New Roles for EVs, miRNA and lncRNA in Bovine Embryo Implantation

The sine qua non of new life is fertilization. However, approximately 50% of fertilized eggs/blastocysts in cattle and up to 75% of those from human assisted reproductive procedures fail during the first 3 to 4 weeks of pregnancy, including peri-implantation periods. In these periods, blastocyst hatching and implantation to the maternal endometrium proceeds, during which physiological events such as epithelial-mesenchymal transition (EMT) and trophoblast cell fusion occur. Quite recently, extracellular vesicles (EVs) with micro RNAs (miRNAs) and long non-coding RNAs (lncRNAs) have been found to play a pivotal role for the establishment of the proper uterine environment required for peri-implantation processes to proceed. New findings of EVs, miRNA, and lncRNAs will be described and discussed to elucidate their connections with conceptus implantation to the maternal endometrium.