Abstract This study evaluated the effects of progesterone (P4) on LH pulse and surge secretion, and hypothalamic neuroendocrine differences between Bos indicus, Bos taurus, and crossbred heifers. Ovariectomized Brahman (n = 8), Hereford (n = 6), and Braford (F1; n = 7) heifers received estradiol (E2) implants to maintain low E2 concentrations. On d − 5, each heifer from the three genetic groups (Gen) was exposed to high P4 (HP4; two CIDRs for 5d), decreasing P4 (DP4; sequential CIDR removal from d − 1.5), and no P4 (NoP4) environments, creating a 3 × 3 crossover factorial design. Serial blood samples were collected for 8h on d − 0.5 (Pulse period) and for 6.5h on d0 (Surge period) following a GnRH challenge (100µg gonadorelin-acetate i.m.) to evaluate LH secretion. Subsequently, hypothalamic tissue was collected for dual-label immunofluorescence of kisspeptin and dynorphin in the arcuate nucleus. Circulating P4 differed among environments (P<0.01) but was not affected by Gen (P = 0.98), with no interaction. LH pulse frequency was reduced under HP4 and increased under DP4 compared to NoP4 (2.7±0.4, 6.7±0.5, and 5.0±0.6 pulses/8h; P<0.01), with no Gen effect (P=0.48). However, Bos indicus heifers exhibited lower LH pulse amplitude and peak than Bos taurus and crossbred (P<0.01). P4 environment did not affect GnRH-induced LH surge (P=0.96), but Bos taurus had greater surge than crossbred and Bos indicus (P<0.01). Additionally, Bos indicus had fewer kisspeptin- and dynorphin-immunopositive neurons in the arcuate nucleus. In conclusion, P4 suppressed LH pulse frequency without altering surge magnitude. Regardless of P4 environment, Bos indicus heifers exhibited reduced LH secretion and fewer kisspeptin/dynorphin neurons than Bos taurus.
Abstract Advances in oncology have significantly improved survival, particularly among children and adolescents with cancer. However, many anti-cancer treatments are gonadotoxic and pose a significant risk to future fertility with important psychosocial consequences for both patients and their families. Fertility preservation should therefore be addressed at diagnosis and prior to treatment initiation. Established strategies include embryo and mature oocyte preservation; however, these options are not feasible for pre-pubertal patients or for those requiring immediate chemotherapy. In such cases ovarian tissue cryopreservation with auto transplantation following remission represents the only available option. This approach can restore both endocrine and fertility. Once considered experimental, ovarian tissue cryopreservation is now considered an established technique, however, further optimization is required to improve efficacy and long-term outcomes, as well as to develop alternative strategies for utilizing tissue unsuitable for transplantation.
Abstract NAD+ is an important regulator of cellular physiological processes. However, in the culture environment, NAD+ levels are predicted to decrease below physiological requirements. Therefore, we examined the effects of the NAD+ precursor nicotinamide mononucleotide (NMN) on NAD+ levels and viability of mammalian fertilized ova. NAD+ levels decreased during in vitro culture, but this decrease was alleviated by NMN. NMN also increased the blastocyst formation rate and accelerated the developmental rate. Transcriptome analysis showed that NMN induced significant changes in the expression of genes involved in mitochondrial function in morula, and that NMN increased mitochondrial membrane potential, oxygen consumption rate and mitochondrial DNA copy number of morula while reducing reactive oxygen species levels. The addition of NMN to the embryo culture medium increased NAD+ levels in embryos, boosted mitochondrial function at the morula stage, and enhanced their ability to develop into blastocysts.
Abstract Male germ cell development begins with spermatogonial stem cell self-renewal and proceeds through meiosis and spermiogenesis, followed by epididymal maturation to generate mature sperm capable of motility and fertilisation. During this process, ATP demands and the physiological environment of germ cells change progressively. Therefore, ATP supply strategies are shaped by adaptation to stage-specific physiological constraints rather than by selection of pathways with the highest energetic efficiency. In the testes, metabolic pathways are remodelled in a stage-dependent manner in response to requirements for stemness and genome stability, changes in substrate availability associated with passage across the blood–testis barrier, energetic demands of meiosis, and extensive cellular reorganisation during spermiogenesis. Although sperm have limited transcriptional and translational capacities in the epididymis, their membrane properties, signalling systems, and metabolic functions mature through exposure to region-specific luminal environments and molecular transfer from the epididymal epithelium. In mature sperm, glycolysis and oxidative phosphorylation are spatially compartmentalised yet functionally coordinated, with their relative contributions adjusted in response to substrate availability, oxygen tension, and functional demand. Additional processes, including carbon recycling potentially mediated by gluconeogenesis-like reactions, may support ATP homeostasis under specific conditions. This review re-evaluates these findings within a unified framework in which physiological constraints define the metabolic pathways available at each developmental stage, thereby reshaping ATP supply strategies. Metabolic remodelling in the testes, maturation in the epididymis, and integration in mature sperm thus represent successive and interconnected processes that establish adaptive ATP supply throughout male germ cell development.
Abstract Preeclampsia (PE) is a major cause of maternal and perinatal morbidity and is increasingly recognized as a disorder involving immune dysregulation. However, reliable candidate biomarkers and key molecular alterations associated with PE remain unclear. We integrated multiple public placental transcriptomic datasets from patients with PE and normotensive controls. Weighted gene co-expression network analysis and eight machine-learning algorithms were used to identify stable immune-related candidate genes, followed by immune infiltration analysis, single-cell analysis, SHAP interpretation, and in silico gene knockout analysis. A six-gene logistic regression model was evaluated in the same merged placental dataset used for feature selection and explored in a small independent peripheral-blood cohort. Frequency-based integration across the eight algorithms identified a six-gene signature comprising ACSS3, F13A1, MCTP1, PTGFR, SLC16A10, and TNFRSF11A. The model showed apparent discrimination in the merged placental dataset (AUC = 0.869, 95% CI: 0.820–0.919) and exploratory cross-tissue discrimination in the peripheral-blood cohort (AUC = 0.860, 95% CI: 0.691–1.000). Immunohistochemical analysis of placental tissues from five women with PE and five normotensive controls showed lower protein abundance of all six candidates in PE, consistent with the bulk transcriptomic findings. Single-cell analysis indicated heterogeneous cell-type-dependent expression patterns, while in silico knockout analysis suggested potential macrophage-associated regulatory effects. Collectively, these exploratory findings identify a six-gene immune-related candidate signature associated with PE that requires validation in larger, prospectively collected cohorts before clinical application.
