Transgenic pig over-expressing leptin as a model for female infertility
Ontology highlight
ABSTRACT: Infertility is a growing global health concern affecting millions of couples worldwide. Both overweight and underweight individuals face reproductive issues, resulting in infertility. Due to small size and short life, mice are not necessarily suitable animal models for human infertility. While, pigs having large size, anatomical and physiological similarities with human are considered as more ideal animal model of human disease. Leptin is a well-known adipokine that serves as an endocrine signal between adiposity and fertility. However, the exact mechanisms underlying leptin's effects on reproductive function remain unclear. To shed light on this, our study focused on pigs genetically engineered to overexpress leptin. These leptin-overexpressing pigs exhibited several reproductive abnormalities, including reduced body weight and size, decreased back fat thickness, and displayed late onset of puberty, and irregular estrous behavior characterized by increased inter-estrous interval and more breeding attempts until pregnancy. This reproductive impairment in leptin pigs was followed by hormonal imbalances and altered steroidogenesis. Bulk RNA sequencing of the ovaries revealed neutrophilic infiltration followed by upregulation of inflammation related genes. To gain a deeper understanding of the cellular levels, we employed single-nucleus RNA sequencing (snRNA-seq), and found that leptin overexpression triggered immune response, suppressed follicle development and luteinization, imposing metabolism dysfunction and hormone imbalance in ovary. Further, trends of phenotypical infertility symptoms and endocrine changes in underweight female patients mirrored the alterations observed in our leptin pigs. These findings suggest that leptin-overexpressing pigs could serve as a valuable animal model for studying infertility and investigating potential therapeutic interventions.
Project description:With rapid economic and social development, people's living habits have changed dramatically. Long-term exposure to artificial light, shift work and staying up late have been found to seriously disrupt people's normal biological rhythms and impair female reproductive function, leading to increased rates of infertility and abortion. In this study, we established a mouse model of continuous light exposure to explore the effects of long-term environmental circadian disturbances on the reproductive endocrine function and related mechanisms in females. We found that continuous light exposure caused reproductive and endocrine metabolic abnormalities in female mice, including estrous cycle disorders, ovarian changes of increased unruptured luteinized cystic follicles, LH elevation and hyperandrogenism. Moreover, the circadian rhythm genes expression in follicular granulosa cells was disrupted, in particular the expression of Nr1d1 showed a significant increase at night. We further showed that the up-regulation of NR1D1 promoted the expression of mitochondrial biosynthesis protein PGC1α and lipid transport related proteins such as SLC27A6, CPT1α, etc, in granulosa cells, and activated the PTEN/PI3K/AKT signaling pathway, leading to premature luteinization of granulosa cells. In addition, the gap junctions between cumulus and oocytes were prematurely closed in COCs treated with NR1D1 agonist GSK4112, which impaired oocyte quality, resulting in reduced maturation, disordered spindle assembly and chromosome arrangement, mitochondrial dysfunction. In conclusion, the circadian clock protein NR1D1 plays an essential role in maintaining granulosa cell endocrine function and oocyte quality. The findings may provide fresh insights into how circadian rhythm disturbances caused by staying up late and continuous exposure to artificial light sources can damage female reproductive function.
Project description:Purpose: To find the difference between leptin-overexpressing and wt pig. Methods: Peripheral blood mononuclear cells (PBMCs) mRNA profiles of 6-month-old wild-type (WT) and leptin-overexpressing pig were generated by deep sequencing. Sequencing libraries were constructed according to the protocol for the Illumina TruSeq Sample preparation kit. Sequencing was performed on the Illumina X Ten sequencer. Library construction and sequencing were performed at the Genergy Biotech Co., Ltd. (Shanghai). Results: RNA-seq was performed to detect the transcriptomic changes in PBMCs in the transgenic leptin pigs. With 2-folds change and p<0.05 threshold, we found that 84 transcripts were upregulated, and 124 transcripts were downregulated in the transgenic leptin pigs. Conclusions: The leptin-overexpressing pigs exhibited remarkable resemblance to human SLE in multiple aspects of the disease.
Project description:The product of the Bmal1 locus is an essential component of the circadian clock that plays important roles in various aspects of reproductive biology,and when disrupted results in infertility. In an effort to establish the identity of the tissue specific clock that is responsible for this infertility, we used the steroidogenic factor-1 (Sf1) promoter to drive Cre-mediated recombination and genetically delete Bmal1 within cells of the reproductive axis. We show that Bmal1 within the reproductive axis of females is essential for normal fertility through its role in maintaining implantation, but is not required for normal estrous cycling. At the root of this biology appears to be a defect in the ovaries, including regulation of ovarian lipid biosynthetic or metabolic processes and their roles in maintaining progesterone synthesis. This conclusion is based upon three observations. First, that deletion of Bmal1 within the reproductive axis reducesleads to affected transcripts in steroidogenic pathways for the LH receptor , and lowers progesterone levels. Second, that progesterone supplementation of these conditional mutants rescues implantation. Third, transplantation of wild type ovaries into Bmal1 reproductive axis mutants rescues fertility. Our study demonstrates the significance of ovarian Bmal1 as an overriding influence in experimental models of infertility. A time series was performed in time-mated C57Bl/6J mice to identiy oscillating transcripts. During the peak and trough of the majority of transcripts (ZT0 and ZT12) samples from Bmal1fx/fx Sf1Cre mice and control litermates as well and global Bmal1 nulls were also analyzed. The tissue types (ovary, pituitary) are not comparable.
Project description:FecB (also known as BMPR1B) is a crucial gene in sheep reproduction, which has a mutation (A746G) that was found to increase the ovulation rate and litter size. The FecB mutation is associated with reproductive endocrinology, such mutation can control external estrous characteristics and affect follicle-stimulating hormone during the estrous cycle. Previous researches showed that the FecB mutation can regulate the transcriptomic profiles in the reproductive-related tissues including hypothalamus, pituitary, and ovary during the estrous cycle of Small Tailed Han sheep (STH). However, little research has been reported on the correlation between FecB mutation and the estrous cycle in STH sheep oviduct. To investigate the coding and non-coding transcriptomic profiles involved in the estrous cycle and FecB in the sheep oviduct, RNA sequencing was performed to analyze the transcriptomic profiles of mRNAs and long non-coding RNAs (lncRNAs) in the oviduct during the estrous cycle of STH sheep with mutant (FecBBB) and wild-type (FecB++) genotypes. In total, 21,863 lncRNAs and 43,674 mRNAs were screened.Together, our results can provide novel insights into the oviductal transcriptomic function against a FecB mutation background in sheep reproduction.
Project description:The product of the Bmal1 locus is an essential component of the circadian clock that plays important roles in various aspects of reproductive biology,and when disrupted results in infertility. In an effort to establish the identity of the tissue specific clock that is responsible for this infertility, we used the steroidogenic factor-1 (Sf1) promoter to drive Cre-mediated recombination and genetically delete Bmal1 within cells of the reproductive axis. We show that Bmal1 within the reproductive axis of females is essential for normal fertility through its role in maintaining implantation, but is not required for normal estrous cycling. At the root of this biology appears to be a defect in the ovaries, including regulation of ovarian lipid biosynthetic or metabolic processes and their roles in maintaining progesterone synthesis. This conclusion is based upon three observations. First, that deletion of Bmal1 within the reproductive axis reducesleads to affected transcripts in steroidogenic pathways for the LH receptor , and lowers progesterone levels. Second, that progesterone supplementation of these conditional mutants rescues implantation. Third, transplantation of wild type ovaries into Bmal1 reproductive axis mutants rescues fertility. Our study demonstrates the significance of ovarian Bmal1 as an overriding influence in experimental models of infertility.
Project description:In pigs, the peri-implantation period is recognized as determinant of successful reproduction, and it is controlled by neuroendocrinal interactions among signals originating from the female hypothalamic-pituitary-ovarian axis, uterus, and developing embryo. The transcriptomic activity of the pituitary gland may influence reproductive processes occurring in pigs during the peri-implantation period. The aim of this study was to determine alternations in gene expression in the porcine pituitary gland during the peri-implantation period (days 15-16 of pregnancy) in comparison with that during the respective days of the estrous cycle using a microarray approach.
Project description:The knowledge regarding the reproductive-status-related changes occurring within the transcriptome of the porcine pituitary is limited. This study aimed to compare pituitary gland gene expression profiles of pigs during the maternal recognition of pregnancy period (days 12-13 of pregnancy) with pigs during the respective days of the estrous cycle using a microarray approach. Analysis indicated 482 differentially expressed genes (DEGs) with a FC ≥ 1.5 (p < 0.05) in the pituitary of pregnant vs. estrous-cyclic pigs. Among them, 68 were up-regulated and 414 were down-regulated. The evaluated DEGs were annotated to 39 gene ontology (GO) biological processes terms, 13 GO cellular components terms, and 10 GO molecular function terms. Among the evaluated DEGs were selected genes coding for proteins potentially involved in the regulation of early pregnancy in pigs and used for gene interaction analysis and validation of microarray results. Analysis of the relationships among DEGs during maternal recognition of pregnancy showed that some of them are connected with, i.e., TGFβ signaling pathway, follicle-stimulating hormone, prolactin, and growth hormone synthesis or activity, adipocytokines responsivity, angiogenesis, immune response, prostaglandin synthesis and inter-pituitary cell to cell interactions. The findings expand the knowledge regarding the molecular mechanisms appearing in the pituitary in pigs during the maternal recognition period of pregnancy.
Project description:While numerous examples of male reproductive disorders have been reported in vertebrates, invertebrate’s organisms have been considerably less studied, despite their ecological importance. The aim of this study is to investigate male infertility in the amphipod Gammarus fossarum, a sentinel species in freshwater risk assessment. Thus in laboratory, we exposed male gammarids to different concentrations of three different xenobiotics: cadmium, and two potent arthropods endocrine-disruptor chemicals, methoxyfenozide and pyriproxyfen. Afterward, we investigated alterations of reproductive health by sperm quality markers and proteomes dynamics on the male reproductive tissue by nanoLC-MS/MS for evidencing proteins modulated by toxic exposure.
Project description:The product of the Bmal1 locus is an essential component of the circadian clock that plays important roles in various aspects of reproductive biology, and its disruption results in infertility. In an effort to identify the identity of the tissue specific clock that is responsible for this infertility, we used the steroidogenic factor-1 (Sf1) promoter to drive Cre-mediated recombination and genetically delete Bmal1 within cells of the reproductive axis. We show that Bmal1 within the reproductive axis of females is essential for normal fertility through its role in maintaining implantation, but is not required for normal estrous cycling. At the root of this biology appears to be a defect in the regulation of ovarian steroidogenic acute regulator (StAR) and its role in maintaining progesterone synthesis. This conclusion is based upon three observations. First, that deletion of Bmal1 within the reproductive axis leads to lower levels of StAR mRNA, and lower progesterone levels. Second, that progesterone supplementation of these conditional mutants rescues implantation. Third, transplantation of wild type ovaries into Bmal1 reproductive axis mutants results in 100% fertility. Our study suggests that ovarian Bmal1 is an essential peripheral clock governing implantation and fertility in female mice.
Project description:Obesity is accompanied by multiple known health risks and increased morbidity, and the prevalence of obesity continues to rise. Fertility in males of reproductive age is affected by the endocrine abnormalities and comorbidities associated with obesity, which has become a primary cause of male infertility. Single-cell RNA sequencing (scRNA-seq) of testes in obese individuals has not been done, so we chose to use this technique to study the mechanism of infertility in an obese mouse model.