Search Results (1,107)

The African catfish (Clarias gariepinus) is an important aquaculture species in the Philippines, but it exhibits reproductive dysfunctions in captivity due to the absence of natural spawning cues and culture-induced stress. In hatcheries, sperm collection often requires sacrificing male breeders, limiting breeding program applications, and threatening genetic diversity. This study evaluated and optimized hormonal induction protocols to enhance spermiation and fertilization success in male C. gariepinus. Two experimental trials were conducted under controlled hatchery conditions. In Trial 1, human chorionic gonadotropin combined with a dopamine antagonist (hCG + DA; 5000 IU·kg⁻¹ BW + 5 mg·kg⁻¹ BW) and Ovaprim (1.0 mL·kg⁻¹ BW) significantly increased circulating testosterone and estradiol levels, spermiation index, and fertilization outcomes (embryo viability, hatching, and larval survival). In Trial 2, medium to low doses of hCG + DA (3000–5000 IU·kg⁻¹ BW + 5 mg·kg⁻¹ BW) and Ovaprim (0.75–1.0 mL·kg⁻¹ BW) yielded the best performance in terms of hormone levels, spermiation index, and fertilizing capabilities. The presence of a dopamine antagonist (DA) likely contributed to the efficacy of the treatments, since dopamine suppresses the secretion of gonadotropin-releasing hormone (dopaminergic inhibition), and DA counteracts this effect, increasing LH and FSH levels necessary for gametogenesis. Taken together, these results highlight the potential of optimized hormonal protocols to mitigate reproductive dysfunctions in male C. gariepinus in aquaculture settings. Further studies should refine dose combinations, assess the long-term health of broodstock, and evaluate cost-effectiveness to support sustainable broodstock management and genetic conservation. Full article

Background/Objectives: Early embryonic arrest during the cleavage stage (days 2–4) accounts for a substantial proportion of developmental failure in in vitro fertilization. This phenomenon remains poorly understood at the molecular level, even in chromosomally normal embryos identified by preimplantation genetic testing. This review aims to redefine cleavage-stage arrest from a passive energy deficit to a checkpoint-regulated endpoint caused by inadequate coordination among metabolism, transcriptome integrity, and stress-response pathways. Methods: We integrate evidence from long-read transcriptomics, metabolomics, epigenetics, and immunobiology relevant to pre-blastocyst development. These data are assembled into a unifying mechanistic framework and a clinically oriented stratification model, together with candidate multimodal readouts for early classification. Results: We propose a three-axis model linking: (i) metabolic–epigenetic insufficiency, including defective histone lactylation and impaired alpha-ketoglutarate-dependent DNA demethylation; (ii) isoform-level abnormalities, including intron retention and retrotransposon activation within a hidden transcriptomic landscape better resolved by long-read sequencing; and (iii) stress-related immune signaling, in which NLRP7 links alternative splicing and DNA-damage-response dysfunction with mitochondrial stress and p53-associated arrest. Within this framework, we distinguish three molecular arrest states: an early transition failure marked by defective maternal-to-embryonic reprogramming and severe splicing disruption; a metabolically quiescent state that may retain a limited rescue window; and a later stress-associated state characterized by senescence-like features, oxidative stress, and broad transcriptomic and genomic instability. Conclusions: Early embryo arrest should no longer be viewed as a nonspecific developmental failure, but as a mechanistically stratifiable condition with distinct metabolic, transcriptomic, and stress-associated trajectories. A diagnostic platform combining fluorescence lifetime imaging microscopy, long-read sequencing, and digital polymerase chain reaction may improve early mechanistic classification, help identify embryos with possible reversibility, and reduce uncertainty in embryo selection during in vitro fertilization. Full article

Effluents from industries, manufacturing companies, textile looms, and floodwater contaminate the surface water reservoirs. This endangers the quality of water for use by humans. Wastewater remediation is one of the ways to recycle the dirty water and make it suitable for use. Photocatalysis is the most common method for wastewater remediation, especially using Titanium dioxide (TiO₂) nanoparticles. However, chemical synthesis and direct addition of nanoparticles may cause toxicity to the flora and fauna present in the water body. To address this limitation, we have green-synthesized TiO₂ nanoparticles using a horticulture waste, Calendula officinalis dried flower extract and entrapped them in a natural polymer, chitosan (CTS-TiO₂-CO nanocomposite). The polymer entrapment ensures biocompatibility as well as reduced aggregation of nanoparticles. The synthesized CTS-TiO₂-CO nanocomposite was characterized using UV-visible spectrophotometry, dynamic light scattering, zeta potential, Fourier Transformed Infrared Spectroscopy (FTIR), X-ray diffractometry (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDAX) analysis. The absorption peak was found at 302 nm, and the hydrodynamic diameter at 490 nm. SEM images show flower-like morphology with 326 nm average particle diameter. The non-toxic dose of the nanoparticles was estimated by MTT assay and zebrafish embryo developmental studies. More than 82% fibroblast cells were viable after treatment with 100 μg/mL of CTS-TiO₂-CO nanocomposite. 85% embryos hatched after treatment with 50 μg/mL of CTS-TiO₂-CO nanocomposite. Further, the textile dye remediation assessment was done using the dye crystal violet, exhibiting 69.19% dye degradation after 4 h of sunlight exposure. Altogether, the results demonstrate that the CTS-TiO₂-CO nanocomposite was effective in the remediation of crystal violet without causing any toxicity up to a dose of 100 μg/mL. Full article

Female reproductive aging is associated with a progressive decline in oocyte competence and reduced success in assisted reproductive technologies. While chromosomal abnormalities, mitochondrial dysfunction, and DNA damage have been extensively studied, these mechanisms do not fully explain developmental arrest in chromosomally euploid embryos or the variability in embryo competence. Human oocytes enter a transcriptionally quiescent state during meiotic maturation and rely almost entirely on the regulated translation of stored maternal messenger RNAs to support fertilization and early embryonic development until zygotic genome activation. In this context, translational fidelity becomes a critical determinant of proteome integrity and cellular function. Age-related alterations affecting ribosomal RNA integrity, transfer RNA modification, aminoacylation accuracy, and translational regulatory networks may impair the precision, timing, and coordination of protein synthesis. These defects can disrupt essential processes such as spindle assembly, cytoskeletal organization, and early cleavage dynamics, ultimately compromising embryo viability despite chromosomal normality. In addition, the follicular microenvironment, including redox balance, metabolic support, and signaling pathways, plays a crucial upstream role in maintaining translational integrity. This review integrates mechanistic evidence from molecular, cellular, and developmental studies to propose that progressive decline in translational fidelity represents a fundamental and previously underrecognized driver of reproductive aging. Understanding translational control as a central regulator of oocyte competence may provide new insights into unexplained IVF failure and support the development of novel biomarkers and therapeutic strategies aimed at preserving reproductive potential. Full article

Background/Objectives: Dynamic remodeling of the zona pellucida (ZP) is a fundamental biochemical and structural process during human preimplantation development; however, its quantitative characterization and clinical relevance remain incompletely defined. The objective of this study was to evaluate dynamic ZP thinning as a functional marker of embryo developmental competence and to examine its relationship with follicular fluid (FF) biomarkers and clinical pregnancy. Methods: This prospective observational study included 47 IVF cycles performed at a single center, yielding 64 transferred blastocysts with complete time-lapse data. ZP thickness was measured from fertilization to 120 h post-fertilization using time-lapse imaging. Two quantitative parameters were derived: the relative thinning ratio (Δrel) and the linear thinning rate (slope). FF concentrations of growth differentiation factor 9 (GDF-9), hyaluronic acid (HA), and syndecan-4 (Syn4) were quantified by ELISA. Embryo-level associations with spontaneous blastocyst hatching were assessed using logistic regression and multivariate analyses, while patient-level models evaluated predictors of clinical pregnancy. Results: Embryos that underwent spontaneous hatching exhibited significantly greater Δrel than non-hatching embryos (p < 0.001). Δrel remained the strongest predictor of hatching in multivariable models (AUC = 0.91). Among FF biomarkers, only GDF-9 showed a positive association with spontaneous hatching. At the patient level, higher Δrel values of transferred embryos were associated with clinical pregnancy (OR 3.65, p = 0.009), whereas FF biomarkers and assisted hatching showed no significant association. Conclusions: Dynamic ZP thinning quantified by Δrel represents a promising indicator of embryo developmental competence. The concordance between embryo-level hatching behavior and patient-level clinical pregnancy suggests potential clinical relevance of ZP dynamics as an integrative embryological marker, warranting validation in larger cohorts. Full article

Three-dimensional (3D) organoid and co-culture models have emerged as transformative tools for studying human endometrial function, implantation, and placental development, overcoming key limitations of animal and two-dimensional in vitro systems. This review synthesises available information of recent advances in endometrial epithelial organoids (EEOs), trophoblast organoids (TBOs), and increasingly complex co-culture platforms incorporating stromal, vascular, and trophoblast compartments to model epithelial–stromal crosstalk, decidualisation, angiogenesis, and embryo implantation. Emerging developments include assembloid systems, synthetic and semi-synthetic extracellular matrices, and microfluidic organ-on-a-chip technologies that enable long-term culture, hormonal responsiveness, and patient-specific modelling. These approaches have recapitulated key features of the mid-secretory endometrium, placental villous architecture, trophoblast differentiation, and early implantation events while revealing disease-associated dysfunctions in conditions such as endometriosis, adenomyosis, polycystic ovarian syndrome, and endometrial cancer. Despite significant progress, current models remain limited by incomplete cellular diversity, polarity constraints, and challenges in fully modelling immune and vascular interactions. Collectively, emerging 3D organoid and co-culture systems provide physiologically relevant platforms to interrogate human reproductive biology, elucidate mechanisms underlying implantation failure and placental disease, and support the development of personalised therapeutic strategies to improve reproductive outcomes. Full article

NKAP (NF-kappa-B-activating protein) is a ubiquitously expressed nuclear protein involved in multiple biological processes. Males with missense NKAP mutations have been reported to present with marfanoid features and behavioral and musculoskeletal abnormalities. We have previously reported that a disruptive NKAP mutation resulted in extremely skewed X chromosome inactivation (XCI), leading to phenotypic manifestation of hemophilia A (HA) in a HA carrier. In this study, with the aim of exploring the phenotypic manifestations of deleterious NKAP mutations in males, as well as their involvement in the mechanism of XCI regulation in females, we generated NKAP mutant mice using CRISPR/Cas9 technology. Gait analysis studies conducted in male mice hemizygous for mutant NKAP by the CatWalk XT system revealed significant alterations in gait parameters, consistent with hypotonia reported in human mutant NKAP patients. By breeding mutant NKAP mice with HA mice, we generated a double heterozygous mutant NKAP/HA mouse model, i.e., female mice carrying mutant NKAP with a WT F8 copy on one X chromosome, and WT NKAP with a mutant F8 copy on the other X chromosome. XCI pattern analysis using methylation-sensitive restriction enzymes demonstrated that mutant NKAP/HA females exhibited significant XCI skewing of the X chromosome bearing the mutant NKAP copy. Furthermore, these females exhibited significantly reduced F8 mRNA levels and FVIII (factor VIII) antigen levels, as demonstrated by quantitative RT-PCR and ELISA, respectively. Murine embryonic fibroblasts (MEFs) derived from a hemizygous mutant NKAP embryo exhibited markedly reduced proliferation rate and increased senescence compared to WT NKAP MEFs, suggesting that XCI skewing induced by mutant NKAP results from secondary selection against cells with an active X chromosome bearing the mutant NKAP copy. Full article

Background: Heterocycle compounds with acridine, quinoline, indole, and pyridine nuclei are potentially active for anticancer activity since they can promote inhibition of vital enzymes, decreasing cell survival after binding to biomolecules. However, unspecific biological interactions can result in unwanted effects, which should be defined during the synthesis and proposition of new molecules. Thus, the objective of this study was to investigate the biological and teratogenic effects of four nitrogen heterocycles proposed for anticancer therapy. Methods: Four 2-cyano-N-phenylacrylamine type derivatives containing acridine (3a), quinoline (3b), indole (3c), and pyridine (3d) nuclei were synthesized and characterized. They were evaluated for their ability to interact with DNA, physicochemical and pharmacokinetic predictions, in vitro and in silico methodologies, besides in vitro inhibition of the Topoisomerase IIα enzyme, antiproliferative activity in tumor and non-tumor cells, hemolytic activity with human erythrocytes, and in vivo toxicological studies with zebrafish embryos. Results: UV–vis absorption studies with ssDNA revealed different spectroscopic effects, with binding constants (Kb) ranging from 1.41 × 10⁵ to 6.46 × 10⁴ M⁻¹. The fluorescence quenching constant (Ksv) with ethidium bromide (EB) varied between 0.53 and 0.67 × 10³ M⁻¹. The compounds intercalated into DNA base pairs, a mechanism confirmed by molecular docking, with 3b (quinoline) showing the most substantial interaction. All derivatives exhibited antitopoisomerase IIα activity at 100 μM and were cytotoxic against MCF-7 and T47-D breast tumor cells, particularly against the more aggressive T47-D lineage. No hemolytic activity was observed in human erythrocytes. In vivo assays in zebrafish embryos showed no toxicological or cardiotoxic effects. However, all compounds altered superoxide dismutase (SOD) and catalase (CAT) enzymatic activity, requiring further studies on reactive oxygen species (ROS) generation to assess potential adverse effects. Furthermore, significant results were observed in the physicochemical and pharmacokinetic parameters of the synthesized compounds. Conclusions: The findings highlight the quinoline derivative (3b) as the most promising nitrogen heterocycle due to its antiproliferative activity and biomolecular interactions without adverse effects in zebrafish embryos, distinguishing it from clinically available agents. Full article

Oxidative stress (OS) and sperm DNA fragmentation (SDF) are complementary contributors to male infertility. OS characterizes a compromised seminal redox status, whereas SDF quantifies downstream genomic damage. Human sperm are highly susceptible to redox damage due to lipid-rich membranes and disrupted post-meiotic DNA-repair capacity. Excess reactive oxygen species (ROS) can cause lipid peroxidation, oxidative base lesions, and DNA strand breaks that impair fertilization, embryo development, and pregnancy outcomes. This review explains how OS promotes genomic instability and summarizes the main laboratory assays that assess redox status and SDF in semen. These include direct ROS chemiluminescence assay, oxidation–reduction potential, total antioxidant capacity/ferric reducing antioxidant power, and lipid peroxidation biomarkers, alongside SDF platforms (Sperm Chromatin Structure Assay, terminal deoxynucleotidyl transferase dUTP nick-end labeling, alkaline/neutral Comet, and sperm chromatin dispersion). Additionally, guideline-aligned indications are highlighted to clarify the conditions for testing OS and SDF. OS testing is most relevant in men with leukocytospermia or suspected genital tract infection or inflammation, including dysbiosis; in cases of major modifiable exposures such as smoking or heat; and for early monitoring after treatment. SDF testing is particularly informative in couples with recurrent pregnancy loss and in unexplained infertility with normal semen parameters. Combined OS and SDF testing is recommended in clinical varicocele, repeated in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) failure, poor embryo development, and follow-up after targeted therapy. Management centers on treating infection and inflammation, improving lifestyle and environmental factors, considering varicocelectomy when indicated, using targeted antioxidant therapy in men with documented OS, and selectively applying sperm selection technologies or testicular sperm for ICSI when SDF remains high. Priorities include assay standardization, etiologic attribution of DNA damage, and trials testing OS/SDF-guided pathways with live birth as the primary endpoint. When used selectively and in the appropriate context, OS and SDF testing can help refine diagnosis, improve counseling, and help personalize care of infertile couples. Full article

Assessing human embryo quality is a critical step in in vitro fertilization (IVF), yet traditional manual grading remains subjective and physically limited by the shallow depth-of-field in conventional microscopy. This study develops a novel “soft optical sensor” architecture that transforms standard optical microscopy into an automated, high-precision instrument for embryo quality assessment. The proposed system integrates two key computational innovations: (1) a multi-focal image fusion module that reconstructs lost morphological details from Z-stack focal planes, effectively creating a 3D-aware representation from 2D inputs; and (2) a retrieval-augmented generation (RAG) framework coupled with a Swin Transformer to provide both high-accuracy classification and explainable clinical rationales. Validated on a large-scale clinical dataset of 102,308 images (prior to augmentation), the system achieves a diagnostic accuracy of 94.11%. This performance surpasses standard single-plane analysis methods by 9.43%, demonstrating the critical importance of fusing multi-focal data. Furthermore, the RAG module successfully grounds model predictions in standard ESHRE consensus guidelines, generating natural language explanations. The results demonstrate that this soft sensor approach significantly reduces inter-observer variability and offers a robust tool for standardized morphological assessment, though prospective validation against live birth outcomes remains essential for clinical adoption. Full article

Background/Objectives: The attention of world science has been focused on human umbilical cord blood cell (hUCB) products for the treatment of various human diseases. The prospects for using hUCB stem from the availability of the material, non-invasive collection procedure, low immunogenicity, multipotency and non-tumorigenicity. But information about the acute toxicity, reproductive and developmental toxicity of hUCB mononuclear cells (MNCs) remains insufficient. Thus, the aim of this study is to assess the reproductive and developmental toxicity of human umbilical cord blood mononuclear cells on Wistar rats. Methods: In the fertility and early embryonic development study, human umbilical cord blood mononuclear cells (hUCB-MNCs) were administered at dose levels of 4.28 × 10⁸ cells/kg and 8.57 × 10⁸ cells/kg to male and female rats during the pre-mating, mating and gestation period. In the embryo–fetal development study, the pregnant female rats also received hUC-MNCs at doses of 4.28 × 10⁸ cells/kg and 8.57 × 10⁸ cells/kg. Results: In gestational data, including fertility rate, pregnancy rate, corpora lutea and implantation sites counts, dead and absorption fetuses’ number, body weight and craniocaudal size of fetuses, anomalies in fetal development showed no statistically significant changes in 4.28 × 10⁸ cells/kg (low dose) and 8.57 × 10⁸ cells/kg (high dose) dose groups of hUCB-MNCs to negative control group. External, visceral and skeletal examination of the fetuses in all experimental groups also showed no changes. Embryo–fetal development study in low and high groups of hUCB-MNCs application also showed no changes in the negative control group. Conclusions: This reproductive and developmental toxicity study demonstrates that hUCB-MNCs administered intravenously at doses up to 8.57 × 10⁸ cells/kg do not cause adverse effects on fertility, embryo–fetal development, or postnatal offspring viability in Wistar rats. The absence of reproductive toxicity is mechanistically attributable to three intrinsic properties of hUCB-MNCs: their low immunogenicity, which prevents maternal immune activation; the protective function of the intact placental barrier; and their transient, paracrine-dominant mode of action, which limits exposure duration. Full article

Human preimplantation embryo arrest (PREMBA) represents a significant clinical hurdle in assisted reproductive technology (ART), in which approximately 10% of in vitro fertilized (IVF) embryos arrest at the cleavage stages. Whole-exome sequencing (WES) studies have discovered numerous genetic mutations associated with preimplantation embryo arrest. These mutations often disrupt critical biological milestones such as maternal mRNA clearance (BTG4, ZFP36L2, ZAR1), subcortical maternal complex (TLE6, PADI6, OOEP, NLRP2, NLRP5, NLRP7, KHDC3L), DNA double-strand break formation and homologous recombination (REC114, TOP6BL, MEI1, MEI4, TRIP13), spindle assembly (TUBB8 and TUBA4A) and cell cycle and checkpoints (FBXO43, MOS, CHEK1, TRIP13, CDC20), as well as nuclear transport and translational regulation (KPNA7, DDOST). However, the cause of most clinical cases remains genetically unexplained. Studies investigating these unexplained arrests have uncovered widespread multi-omics abnormalities, including transcriptional arrest, DNA hypermethylation, higher chromatin accessibility, aberrant histone modification, chromosomal aneuploidy and senescent-like states. This review provides a comprehensive overview of the molecular mechanisms underlying PREMBA, categorized into those that are attributable to known genetic mutations and those with unexplained reasons. Full article

Three-dimensional (3D) cell culture models provide physiologically relevant systems that mimic the native endometrial environment better than 2D models and offer reliable platforms to study embryo implantation and maternal–embryo interactions. One widely used 3D culture model is the generation of spheroids. However, standardized and reproducible methods for generating uniform spheroids from trophoblast and endometrial stromal cells are limited. In this study, we established and validated a robust protocol for spheroid formation using human trophoblast (HTR8/SVneo, JEG3) and endometrial stromal (St-T1b, tHESC) cell lines. The protocol was further extended to generate spheroids from decidualized tHESC, representing a novel approach that closely reflects the receptive endometrial environment. Key parameters, including cell concentration and methyl cellulose supplementation, were optimized to produce compact and homogeneous spheroids. Spheroid formation was monitored at defined intervals (0, 8, 24, 32, and 48 h), and decidualized spheroids were assessed up to 72 h. Long-term cryopreservation over 11 months demonstrated high post-thaw viability across all spheroid types, as confirmed by Calcein-AM staining. This standardized workflow provides a reliable 3D model incorporating hormonally primed stromal cells and offers a practical platform to investigate the mechanisms underlying normal and trophoblast invasion in vitro. Full article

Embryo implantation presents a cell biological paradox: contact formation between the trophoblast of the blastocyst and the epithelial lining of the endometrium contradicts typical epithelial cell behaviour, as does the subsequent invasion needed for placenta formation in most species (including the human). Explaining this conundrum became a challenge for investigation since its recognition about 40 years ago and it receives increasing interest because implantation failure appears to be a major cause for low success in assisted reproduction. The present article reviews the main findings that have directed attention of researchers on epithelial cell polarity and on the theoretical concept of epithelial–mesenchymal transition (EMT). Apart from trophoblast attachment competence, a special focus is on endometrial receptivity. Comparison with epithelial fusion processes (EFPs) in development and with tumour cell invasion has been and is still considered helpful in order to take advantage of the progress made in those fields. Concerning the mechanisms involved, it must be emphasized that trophoblast and uterine luminal epithelium (ULE) do not undergo a complete switch to a mesenchymal programme (do not undergo a complete EMT) but make use of partial changes in the epithelial programme. The large number of data accumulated recently should allow us to now make progress in identifying what these partial programme changes are exactly and how they are regulated; also, they may offer chances for obtaining deeper insights into the regulation of implantation. Full article

The rhesus macaque is one of the closest evolutionary relatives to humans, making the study of alternative splicing (AS) during its early embryonic development highly valuable for understanding human embryogenesis and related diseases. However, systematic studies in this context remain limited. Here, a comprehensive bioinformatic analysis of AS was performed using RNA-seq data spanning early rhesus macaque embryogenesis. We identified multiple previously unannotated zygotic genome activation (ZGA) genes, thereby refining the rhesus macaque ZGA gene repertoire. The landscape of AS and differential AS events (DASEs) across early stages was characterized, revealing dynamic and stage-specific regulation, with a marked increase in AS events from the 8-cell to morula stages. In addition, weighted gene co-expression network analysis identified 35 key splicing factors (SFs) involved in regulating early rhesus macaque embryonic development. Finally, we calculated the correlation between differentially expressed SFs and DASEs during the ZGA process, and identified potential regulatory relationships between several SFs (TRA2B, IGF2BP1, HNRNPAB, and MATR3) and specific DASEs. Collectively, this study provides the first systematic analysis of AS dynamics and regulation in early rhesus macaque embryogenesis, highlighting its critical role in development and offering a valuable reference for understanding AS in early human embryos. Full article