Hypogonadism Associated with Cyp19a1 (Aromatase) Posttranscriptional Upregulation in Celf1 Knockout Mice

In-utero exposure to real-life environmental chemicals disrupts gene expression within the hypothalamo-pituitary-gonadal axis of prepubertal and adult rams

Environmental chemicals (ECs) have been associated with a broad range of disorders and diseases. Daily exposure to various ECs in the environment, or real-life exposure, has raised significant public health concerns. Utilizing the biosolids-treated pasture (BTP) sheep model, this study demonstrates that in-utero exposure to a real-life EC mixture disrupts hypothalamo-pituitary-gonadal (HPG) axis gene expression and reproductive traits in prepubertal (8-week-old, 8w) and adult (11-month-old) male sheep. Ewes were maintained on either BTP or pastures fertilized with inorganic fertilizer [control (C)] from approximately one month prior to insemination until around parturition. Thereafter, all animals were kept under control conditions. Effects on reproductive parameters including testosterone concentrations and the expression of key genes in the HPG axis were evaluated in eight-week-old and adult male offspring from both C and biosolids-exposed (B) groups. Results showed that, at 8w, relative to C (n = 11), B males (n = 11) had lower body weight, and altered testicular expression of HSD3B1, LHR and HSD17B3, BMP4, ABP, P27kip and CELF1. Principal component analysis (PCA) identified two 8w B subgroups, based on hypothalamic expression of GnRH, ESR1, and AR, and pituitary expression of KISSR. The two subgroups also exhibited different serum testosterone concentrations. The largest biosolids effects were observed in the hypothalamus of adult rams with NKB, ESR1, KISS1, AR, DLK1 and GNRH1 mRNA expression differing between B (n = 10) and C (n = 11) rams. Testicular steroidogenic enzymes CYP11A1 and HSD3B1 mRNA expression also differed between exposure groups. PCA identified two adult B subgroups, with BS1 (n = 6) displaying hypothalamic effects and BS2 (n = 4) both hypothalamic and testicular effects. The subgroups also differed in circulating testosterone concentrations. These findings demonstrate that exposure to a real-life EC mixture may predispose some males to infertility, by disrupting key functional HPG markers before puberty with consequent downstream effects on steroid hormones and spermatogenesis.

Multi-Omics Approaches Uncovered Critical mRNA-miRNA-lncRNA Networks Regulating Multiple Birth Traits in Goat Ovaries

The goat breeding industry on the Tibetan Plateau faces strong selection pressure to enhance fertility. Consequently, there is an urgent need to develop goat lines with higher fertility and adaptability. The ovary, as a key organ determining reproductive performance, is regulated by a complex transcriptional network involving numerous protein-coding and non-coding genes. However, the molecular mechanisms of the key mRNA-miRNA-lncRNA regulatory network in goat ovaries remain largely unknown. This study focused on the histology and differential mRNA/miRNA/lncRNA between Chuanzhong black goat (CBG, high productivity, multiple births) and Tibetan goat (TG, strong adaptability, single birth) ovaries. Histomorphological analysis showed that the medulla proportion in CBG ovaries was significantly reduced compared to TG. RNA-Seq and small RNA-Seq analysis identified 1218 differentially expressed (DE) mRNAs, 100 DE miRNAs, and 326 DE lncRNAs, which were mainly enriched in ovarian steroidogenesis, oocyte meiosis, biosynthesis of amino acids and protein digestion, and absorption signaling pathways. Additionally, five key mRNA-miRNA-lncRNA interaction networks regulating goat reproductive performance were identified, including TCL1B-novel68_mature-ENSCHIT00000010023, AKAP6-novel475_mature-ENSCHIT00000003176, GLI2-novel68_mature-XR_001919123.1, ITGB5-novel65_star-TCONS_00013850, and VWA2-novel71_mature-XR_001919911.1. Further analyses showed that these networks mainly affected ovarian function and reproductive performance by regulating biological processes such as germ cell development and oocyte development, which also affected the plateau adaptive capacity of the ovary by participating in the individual immune and metabolic capacities. In conclusion, we identified numerous mRNA-miRNA-lncRNA interaction networks involved in regulating ovarian function and reproductive performance in goats. This discovery offers new insights into the molecular breeding of Tibetan Plateau goats and provides a theoretical foundation for developing new goat lines with high reproductive capacity and strong adaptability to the plateau environment.

Population structure and selection signal analysis of indigenous sheep from the southern edge of the Taklamakan Desert

Analyzing the genetic diversity and selection characteristics of sheep (Ovis aries) holds significant value in understanding their environmental adaptability, enhancing breeding efficiency, and achieving effective conservation and rational utilization of genetic resources. In this study, we utilized Illumina Ovine SNP 50 K BeadChip data from four indigenous sheep breeds from the southern margin of the Taklamakan Desert (Duolang sheep: n = 36, Hetian sheep: n = 74, Kunlun sheep: n = 27, Qira black sheep: n = 178) and three foreign meat sheep breeds (Poll Dorset sheep: n = 105, Suffolk sheep: n = 153, Texel sheep: n = 150) to investigate the population structure, genetic diversity, and genomic signals of positive selection within the indigenous sheep. According to the Principal component analysis (PCA), the Neighbor-Joining tree (NJ tree), and Admixture, we revealed distinct clustering patterns of these seven sheep breeds based on their geographical distribution. Then used Cross Population Extended Haplotype Homozygosity (XP-EHH), Fixation Index (FST), and Integrated Haplotype Score (iHS), we identified a collective set of 32 overlapping genes under positive selection across four indigenous sheep breeds. These genes are associated with wool follicle development and wool traits, desert environmental adaptability, disease resistance, reproduction, and high-altitude adaptability. This study reveals the population structure and genomic selection characteristics in the extreme desert environments of native sheep breeds from the southern edge of the Taklimakan Desert, providing new insights into the conservation and sustainable use of indigenous sheep genetic resources in extreme environments. Additionally, these findings offer valuable genetic resources for sheep and other mammals to adapt to global climate change.

Molecular Mechanism of Circ_0088300-BOLL Interaction Regulating Mitochondrial Metabolic Reprogramming and Involved in Gastric Cancer Growth and Metastasis

This study aims to investigate the effect and molecular mechanism of the interaction between circRNA circ_0088300 and the RNA binding protein (RBP) BOLL on the growth and metastasis of gastric cancer. A prognostic risk model was established by screening differentially expressed RBP genes from the TCGA database, and BOLL was identified as a critical RBP. Gene Set Enrichment analysis (GSEA) showed that BOLL was associated with mitochondrial function. The upregulation fold change of circ_0088300 was the highest in the GSE93541 data set, and the RPISeq database confirmed its binding relationship with BOLL. In vitro experiments showed that BOLL regulates mitochondrial metabolism and cancer cell function and circ_0088300 upregulates the expression level of BOLL. In vivo experiments demonstrated that knocking down circ_0088300 can inhibit tumor growth and metastasis, whereas overexpression of BOLL can reverse this effect. In conclusion, we have reached a preliminary conclusion that upregulation of BOLL by circ_0088300 promotes gastric cancer growth and metastasis by promoting mitochondrial metabolic reprogramming.

Role of CYP19A1 Loci (rs28757157 and rs3751591) with Ischemic Stroke Risk in the Chinese Han Population

Introduction

Ischemic stroke (IS) is a multifactorial and polygenic disease, which is affected by genetic factors. In this study, we explored the role of CYP19A1 single nucleotide polymorphisms (SNPs) in IS in the Chinese population.

Methods

1302 subjects (651 controls and 651 cases) were recruited in this case-control study. Four candidate SNPs (rs28757157 C/T, rs3751592 C/T, rs3751591 G/A, rs59429575 C/T) of CYP19A1 were selected by the 1000 genomes project database. The association between CYP19A1 SNPs and IS risk was assessed using logistic regression analysis with odds ratio (OR) and 95% confidence intervals (CIs). False-positive report probability (FPRP) analysis further verified the positive results. The interaction of SNP-SNP was analyzed by multi-factor dimensionality reduction (MDR) to predict is risk.

Results

In the research, CYP19A1 loci (rs28757157 and rs3751591) were associated with the occurrence of IS. The two variants conferred an increased susceptibility to IS in the subjects aged over 60 years old, smokers and drinkers. Rs28757157 was related to the risk of IS in females, non-smokers and subjects with BMI less than 24, while rs59429575 was related to the risk of IS in males and subjects with BMI greater than 24.

Conclusion

The study revealed that there is a significant association between CYP19A1 loci (rs28757157 and rs3751591) and IS risk in the Chinese Han population, providing a theoretical basis for further exploring its specific role in the pathogenesis of IS.

CELF1 represses Doublesex1 expression via its 5' UTR in the crustacean Daphnia magna

In sex determination of the crustacean Daphnia magna, male-specific expression of DM-domain transcription factor Doublesex1 (Dsx1) orchestrates the male developmental program triggered by environmental stimuli. We previously identified the CELF1 ortholog as a candidate of proteins associated with the 5' UTR of the Dsx1α isoform. Here we report the CELF1-dependent suppression of Dsx1 expression in D. magna. During embryogenesis, CELF1 expression was not sexually dimorphic. Silencing of CELF1 led to the activation of Dsx1 expression both in female and male embryos. Overexpression of CELF1 in male embryos resulted in a reduction of Dsx1 expression. By these manipulations of CELF1 expression, the Dsx1 transcript level was not significantly changed. To investigate whether the CELF1 controls Dsx1 expression via its 5' UTR, we injected the GFP reporter mRNA having intact Dsx1α 5' UTR or mutated one lacking the GU-rich element (GRE) that is known as a binding site of the CELF1 ortholog. We found that deletion of the GRE significantly increased the reporter gene expression. These results indicate that CELF1 suppresses Dsx1 expression both in females and males, possibly at the post-transcriptional level. We speculate that CELF1 may avoid unintended Dsx1 expression and generation of sexual ambiguity by setting a threshold of Dsx1 expression.

Multi Species Analyses Reveal Testicular T3 Metabolism and Signalling as a Target of Environmental Pesticides

Thyroid hormones (THs) regulate many biological processes in vertebrates, including reproduction. Testicular somatic and germ cells are equipped with the arrays of enzymes (deiodinases), transporters, and receptors necessary to locally maintain the optimal level of THs and their signalling, needed for their functions and spermatogenesis. Pesticides, as chlorpyrifos (CPF) and ethylene thiourea (ETU), impair the function of thyroid and testis, affecting male fertility. However, their ability to disarrange testicular T3 (t-T3) metabolism and signalling is poorly considered. Here, a multi-species analysis involving zebrafish and mouse suggests the damage of t-T3 metabolism and signalling as a mechanism of gonadic toxicity of low-doses CPF and ETU. Indeed, the developmental exposure to both compounds reduces Dio2 transcript in both models, as well as in ex-vivo cultures of murine seminiferous tubules, and it is linked to alteration of steroidogenesis and germ cell differentiation. A major impact on spermatogonia was confirmed molecularly by the expression of their markers and morphologically evidenced in zebrafish. The results reveal that in the adopted models, exposure to both pesticides alters the t-T3 metabolism and signalling, affecting the reproductive capability. Our data, together with previous reports suggest zebrafish as an evaluable model in assessing the action of compounds impairing locally T3 signalling.

A Testis-Specific Long Noncoding RNA, Start, Is a Regulator of Steroidogenesis in Mouse Leydig Cells

The testis expresses many long noncoding RNAs (lncRNAs), but their functions and overview of lncRNA variety are not well understood. The mouse Prss/Tessp locus contains six serine protease genes and two lncRNAs that have been suggested to play important roles in spermatogenesis. Here, we found a novel testis-specific lncRNA, Start (Steroidogenesis activating lncRNA in testis), in this locus. Start is 1822 nucleotides in length and was found to be localized mostly in the cytosol of germ cells and Leydig cells, although nuclear localization was also observed. Start-knockout (KO) mice generated by the CRISPR/Cas9 system were fertile and showed no morphological abnormality in adults. However, in adult Start-KO testes, RNA-seq and qRT-PCR analyses revealed an increase in the expression of steroidogenic genes such as Star and Hsd3b1, while ELISA analysis revealed that the testosterone levels in serum and testis were significantly low. Interestingly, at 8 days postpartum, both steroidogenic gene expression and testosterone level were decreased in Start-KO mice. Since overexpression of Start in two Leydig-derived cell lines resulted in elevation of the expression of steroidogenic genes including Star and Hsd3b1, Start is likely to be involved in their upregulation. The increase in expression of steroidogenic genes in adult Start-KO testes might be caused by a secondary effect via the androgen receptor autocrine pathway or the hypothalamus-pituitary-gonadal axis. Additionally, we observed a reduced number of Leydig cells at 8 days postpartum. Collectively, our results strongly suggest that Start is a regulator of steroidogenesis in Leydig cells. The current study provides an insight into the overall picture of the function of testis lncRNAs.

Effect of shell as natural testosterone boosters in Sprague Dawley rats

Aim:

This study aimed to evaluate the effect of shell supplementation on the regulation of male reproduction in rats

Materials and Methods:

The zinc (Zn) level of shell from blood clam (Anadara granosa), green mussel (Perna viridis), and conch shell (Telescopium telescopium) was analyzed. The highest Zn content shell was fed to male Sprague Dawley rats for 0, 9, 30, and 50 days at the dose of either 0.09 mg/200 g BW or 0.18 mg/200 g BW. To determine the testosterone levels, blood was collected through the infraorbitalis sinus just before the rat was sacrificed. Testicular and brain were also collected for Cyp19 aromatase receptor analysis.

Results:

The Zn level in the shell of blood clam, green mussel, and conch shell 61.55 mg/kg, 2.78 mg/kg, and 3.93 mg/kg, respectively. The testosterone level of T1 group receiving 0.18 mg/200 g BW for 0, 9, 30, and 50 days was 1.42±0.59, 2.15±1.58, 2.98±2.53, and 8.11±2.03 ng/mL, respectively. The testosterone level of T2 group receiving 0.09 mg/200 g BW for 0, 9, 30, and 50 days was 2.50±0.32, 1.25±0.60, 3.87±3.27, and 3.54±0.23 ng/mL, respectively. The T3 group receiving Na-CMC showed the level of testosterone at days 0, 9, 30, and 50 days was 0.77±0.22, 1.99±1.65, 4.12±0.07, and 2.19±1.30 ng/mL, respectively. Finally, the T4 group receiving Zn showed testosterone levels at days 0, 9, 30, and 50 days was 0.51±0.58, 2.24±3.16, 4.58±1.97, and 2.89±0.20 ng/mL, respectively. There was a significant difference (p<0.05) between the T1 group compared to the other groups. However, the absence of expression of Cyp19 aromatase both in Leydig cells and the brain indicated no conversion of testosterone to estradiol. To add, this finding showed the potential use of the shell to boost the testosterone level in male rats.

Conclusion:

Shell acted as an aromatase blocker to boost the testosterone level in male rats. This also indicates its promising application in birds to manipulate the quality of song and feather.

A novel evolutionary conserved mechanism of RNA stability regulates synexpression of primordial germ cell-specific genes prior to the sex-determination stage in medaka

Dmrt1 is a highly conserved transcription factor, which is critically involved in regulation of gonad development of vertebrates. In medaka, a duplicate of dmrt1-acting as master sex-determining gene-has a tightly timely and spatially controlled gonadal expression pattern. In addition to transcriptional regulation, a sequence motif in the 3' UTR (D3U-box) mediates transcript stability of dmrt1 mRNAs from medaka and other vertebrates. We show here that in medaka, two RNA-binding proteins with antagonizing properties target this D3U-box, promoting either RNA stabilization in germ cells or degradation in the soma. The D3U-box is also conserved in other germ-cell transcripts, making them responsive to the same RNA binding proteins. The evolutionary conservation of the D3U-box motif within dmrt1 genes of metazoans-together with preserved expression patterns of the targeting RNA binding proteins in subsets of germ cells-suggest that this new mechanism for controlling RNA stability is not restricted to fishes but might also apply to other vertebrates.