Maternal metabolism affects endometrial expression of oxidative stress and FOXL2 genes in cattle

Impact of carob (Ceratonia siliqua L.) pulp inclusion and warm season on gastrointestinal morphological parameters, immune-redox defences and coccidiosis in concentrate-fed light lambs

This study aimed to evaluate the effects of dietary carob (Ceratonia siliqua L.) pulp and warm season on gastrointestinal morphological parameters, immune-redox defences and coccidiosis in concentrate-fed light lambs. Weaned lambs were assigned to one of three concentrate-based diets: C0 (without carob pulp), C15 (150 g/kg of carob pulp) and C30 (300 g/kg of carob pulp) from 40 to 80 days of age in two consecutive cold and warm batches. Blood samples were collected at Day 80 to determine the metabolic status. Rectal faeces were sampled at Days 50, 65 and 80 to determine consistency and oocyst count per gram. Inclusion of carob pulp in lamb diets did not affect lamb growth but reduced coccidia oocyst excretion, improved faecal consistency and gastrointestinal morphological parameters, enhancing the ruminal thickness of the papilla living strata and reducing the darkness of the epithelium colour. Moreover, carob condensed tannins in the lambs' diet enhanced the expression of antioxidant SOD2 in rumen, while down-regulated NRF2, SOD1, CAT and PPARG in ileum. There was no interaction between the treatments and season in the evaluated variables. Lambs from the warm season exhibited reduced growth performance, altered ruminal epithelium, lower circulating iron levels, increased protein concentrations and higher coccidiosis susceptibility. In addition, regulatory immune and antioxidant mechanisms to counterbalance reactive oxygen species production in gastrointestinal tissues were evident. Dietary inclusion of carob pulp (150 and 300 g/kg) in lamb diets improved gastrointestinal health and homeostasis but did not ameliorate the deleterious effects of warm season.

Characterization of Beta-Lactam Resistance Genes and Virulence Factors Associated with Multidrug-Resistant Klebsiella pneumoniae Isolated from Patients at Major Hospitals in Trinidad, West Indies

Accurate species identification and antibiotic resistance profiling are essential for the effective management of infections caused by bacterial pathogens. In this study, 373 clinical isolates of K. pneumoniae from major hospitals in Trinidad, West Indies, were characterized for resistance against beta-lactam antibiotics and the presence of genes encoding important virulence factors. Most of the isolates showed extended spectrum β-lactamase (ESBL) activity but few also displayed carbapenemase or 'ESBL + carbapenemase' activities. Polymerase chain reaction analysis revealed the presence of genes for ESBL subtypes bla_TEM, bla_SHV, and bla_CTX-M that were dominant in isolates with the ESBL phenotype as well as those that did not show ESBL or carbapenemase activities. The carbapenem resistance gene, bla_KPC, and the metallo-β-lactamase (MBL) gene, bla_NDM-1, were also detected in some of the isolates. Multiple virulence genes were also detected, but the fimH-uge was the most common combination found among the local isolates. The findings of this study represent the first comprehensive study on the prevalence of ESBL, KPC and MBL genes and virulence profiling in antibiotic-resistant K. pneumoniae in Trinidad. Furthermore, the occurrence of multiple resistant phenotypes and gene combinations were revealed, though at low prevalence rates. This work emphasizes the need to implement molecular-based techniques in diagnostic workflows for rapid and accurate species identification and profiling of resistance and virulence genes in K. pneumoniae in Trinidad and Tobago.

Screening and validation of reference genes for qRT-PCR of bovine skeletal muscle-derived satellite cells

The accuracy of sixteen commonly used internal reference genes was assessed in skeletal muscle-derived satellite cells of Qinchuan cattle at different stages of proliferation and induction of differentiation to determine the most suitable ones. Quantitative real-time PCR and three commonly used algorithmic programs, GeNorm, NormFinder and BestKeeper, were used to evaluate the stability of expression of the candidate internal reference genes (GAPDH, ACTB, PPIA, LRP10, HPRT1, YWHAZ, B2M, TBP, EIF3K , RPS9, UXT, 18S rRNA, RPLP0, MARVELD, EMD and RPS15A) in skeletal muscle-derived satellite cells at 0, 12, 24, 36 and 48 h of growth and after differentiation for 0, 2, 4, 6 and 8 days. The expression of two satellite cell marker genes, CCNA2 and MYF5, was used for validation analysis. The results of the software analyses showed that GAPDH and RPS15A were the most stable reference gene combinations during in vitro proliferation of bovine skeletal muscle-derived satellite cells, RPS15A and RPS9 were the most stable reference gene combinations during in vitro induction of differentiation of the cells, and PPIA was the least stable reference gene during proliferation and differentiation and was not recommended. This study lays the foundation for the selection of reference genes for qRT-PCR during the proliferation and induction of differentiation of bovine skeletal muscle-derived satellite cells.

The presence of an embryo affects day 14 uterine transcriptome depending on the nutritional status in sheep. b. Immune system and uterine remodeling

Transcriptomics and bioinformatics were used to investigate the potential interactions of undernutrition and the presence of the conceptus at the time of maternal recognition of pregnancy on uterine immune system and remodeling. Adult Rasa Aragonesa ewes were allocated to one of two planes of nutrition for 28 days: maintenance energy intake (control; 5 cyclic, 6 pregnant ewes) providing 7.8 MJ of metabolisable energy and 0.5 maintenance intake (undernourished; 6 cyclic, 7 pregnant ewes) providing 3.9 MJ of metabolisable energy per ewe. Uterine gene expression was measured using Agilent 15 K Sheep Microarray chip on day 14 of estrus or pregnancy. Functional bioinformatics analyses were performed using PANTHER (Protein ANalysis THrough Evolutionary Relationships) Classification System. Pregnancy affected the expression of 18 genes in both control and undernourished ewes, underscoring the relevance for embryo-maternal interactions. Immune system evidenced by classical interferon stimulated genes were activated in control and -in a lesser extent-in undernourished pregnant vs cyclic ewes. Genes involved in uterine remodeling such as protein metabolism were also upregulated with the presence of an embryo in control and undernourished ewes. However, relevant genes for the adaptation of the uterus to the embryo were differentially expressed between pregnant vs cyclic ewes both in control and undernourished groups. Undernutrition alone led to an overall weak activation of immune system pathways both in cyclic and pregnant ewes. Data revealed that cellular and immune adaptations of the uterus to pregnancy are dependent on the nutritional status.

Identification of reliable reference genes for expression studies in maternal reproductive tissues and foetal tissues of pregnant cows

The relationship between the conceptus and the maternal uterine environment is crucial for the successful establishment and maintenance of pregnancy in cattle. Gene expression analysis of the conceptus and maternal reproductive tissues is a favourable method to assess the embryonic maternal interaction. The reliability of the commonly used method reverse transcription-quantitative polymerase chain reaction (RT-qPCR) depends on proper normalization to stable reference genes (RGs). The objective of this study was to determine the expression stability of 10 potential RGs in maternal reproductive tissues and foetal tissues, and to analyse the effect of RG selection on the calculation of the relative expression of target genes. The expression stability of 10 potential RGs was analysed in eight different tissues from three pregnant dairy cows. Three programs-GeNorm, NormFinder and Bestkeeper-were used to identify the best RGs. According to all three programs, the most stable RG was CNOT11, whereas the least stable RGs were GAPDH and HPRT1. GeNorm analysis showed that a combination of five RGs (SDHA, PPIA, CNOT11, RPS9 and RPL19) was necessary for appropriate data normalization. However, NormFinder analysis indicated that the combination of CNOT11 and PPIA was the most suitable. When target genes were normalized to these RGs, the relative expression of the Radical S-adenosyl methionine domain containing 2 gene was not affected by the choice of RGs, whereas a large difference was observed in the expression profile of the Nuclear erythroid2-related factor 2 gene between the most stable and least stable RGs. The results indicate that careful selection of RGs is crucial under different conditions, especially for target genes with relatively small fold changes. Furthermore, the results provide useful information for the selection of RGs for evaluating genes affecting bovine reproduction.

Challenges in studying preimplantation embryo-maternal interaction in cattle

A comprehensive understanding of the complex embryo-maternal interactions during the preimplantation period requires the analysis of the very early stages of pregnancy encompassing early embryonic development, maternal recognition and the events leading to implantation. Despite the fact that embryo development until blastocyst stage is somewhat autonomous (i.e., does not require contact with the maternal reproductive tract and can be successfully recapitulated in vitro), many studies on ruminant embryo production have focused on the fundamental question of why: (i) only 30%-40% of immature oocytes develop to the blastocyst stage and (ii) the quality of such blastocysts continually lags behind that of blastocysts produced in vivo. Clear evidence indicates that in vitro culture conditions are far from optimal with deficiencies being manifested in short- and long-term effects on the embryo. Thus, enhanced knowledge of mechanisms controlling embryo-maternal interactions would allow the design of novel strategies to improve in vitro embryo conditions and reproductive outcomes in cattle.

Fine-tuned adaptation of embryo-endometrium pairs at implantation revealed by transcriptome analyses in Bos taurus

Interactions between embryo and endometrium at implantation are critical for the progression of pregnancy. These reciprocal actions involve exchange of paracrine signals that govern implantation and placentation. However, it remains unknown how these interactions between the conceptus and the endometrium are coordinated at the level of an individual pregnancy. Under the hypothesis that gene expression in endometrium is dependent on gene expression of extraembryonic tissues and genes expressed in extraembryonic tissues are dependent of genes expressed in the endometrium, we performed an integrative analysis of transcriptome profiles of paired extraembryonic tissue and endometria obtained from cattle (Bos taurus) pregnancies initiated by artificial insemination. We quantified strong dependence (|r| > 0.95, empirical false discovery rate [eFDR] < 0.01) in transcript abundance of genes expressed in the extraembryonic tissues and genes expressed in the endometrium. The profiles of connectivity revealed distinct coexpression patterns of extraembryonic tissues with caruncular and intercaruncular areas of the endometrium. Notably, a subset of highly coexpressed genes between extraembryonic tissue (n = 229) and caruncular areas of the endometrium (n = 218, r > 0.9999, eFDR < 0.001) revealed a blueprint of gene expression specific to each pregnancy. Gene ontology analyses of genes coexpressed between extraembryonic tissue and endometrium revealed significantly enriched modules with critical contribution for implantation and placentation, including “in utero embryonic development,” “placenta development,” and “regulation of transcription.” Coexpressing modules were remarkably specific to caruncular or intercaruncular areas of the endometrium. The quantitative association between genes expressed in extraembryonic tissue and endometrium emphasize a coordinated communication between these two entities in mammals. We provide evidence that implantation in mammalian pregnancy relies on the ability of the extraembryonic tissue and the endometrium to develop a fine-tuned adaptive response characteristic of each pregnancy.

An integrative analysis of interactions between conceptus and endometrium, in cattle, reveals complex regulatory networks operating at the time of implantation, highlighting the unique transcriptional blueprint of conceptus-maternal communication

Implantation in mammals requires a complex crosstalk between the conceptus (the embryo and associated membranes) and the uterus. An imbalanced regulation of the factors contributing to these interactions has negative impacts on the attachment of the fetus, the progression of the pregnancy, and the progeny. Focusing on paired conceptus–endometrium analyses of individual pregnancies in cows, we have determined that communication at implantation encompasses synchronized genome-wide coregulation of genes. Gene regulatory interactions between one conceptus and the surrounding maternal tissue vary between endometrial regions containing or lacking glands. Our data reveal new insights, to our knowledge, on the coordination of molecular mechanisms that contribute to implantation and pregnancy establishment in mammals. We conclude that the biological response of the endometrium is embryo-specific, a phenomenon that deserves further investigation in the context of assisted reproductive technologies.

Rsad2 is necessary for mouse dendritic cell maturation via the IRF7-mediated signaling pathway

Dendritic cells (DCs) are the most potent professional antigen presenting cells and inducers of T cell-mediated immunity. However, few specific markers of mature DCs (mDC) have been reported. A previous microarray analysis revealed expression of mDC-specific genes and identified Rsad2 (radical S-adenosyl methionine domain containing 2) as a candidate specific marker for DC maturation. Mouse bone marrow-derived DCs were transfected with Rsad2 siRNA and examined by flow cytometry, ELISA, western, and confocal microscopy. C57BL/6 mice received intravenously B16F10 cells to establish a pulmonary metastasis model. Tumor-bearing mice then received subcutaneously two injections of mDCs or Rsad2 knockdown DCs. The cytotoxic T lymphocyte (CTL) population was examined from splenocytes of DC-vaccinated mice by flow cytometry. Rsad2 was induced at high levels in LPS-stimulated mDCs and mDC function was markedly attenuated under conditions of Rsad2 knockdown. Moreover, Rsad2 was necessary for mDC maturation via the IRF7-mediated signaling pathway. The importance of Rsad2 was confirmed in an Rsad2 knockdown lung metastasis mouse model in which mDCs lost their antitumor efficacy. Data on the CTL population further supported the results as above. Taken together, Rsad2 was an obvious and specific marker necessary for DC maturation and these findings will be clearly helpful for further understanding of DC biology.