In vivo effect of vaginal seminal plasma application on the human endometrial transcriptome: a randomized controlled trial.

Studies in humans and animals suggest that seminal plasma, the acellular seminal fluid component, stimulates the endometrium to promote immune tolerance and facilitate implantation. We designed a randomized, double-blinded, placebo-controlled trial to investigate changes in the endometrial transcriptomic profile after vaginal application of seminal plasma. The study participants were randomized into two groups. Five women received a vaginal application of seminal plasma, and four received a placebo application with saline solution. The application was performed 2 days after HCG-triggered ovulation in an unstimulated cycle. After 5-8 days, an endometrial biopsy was collected to analyze differences in the endometrial transcriptomic profile using microarray analyses. A differential gene expression analysis and a gene set analysis were performed. The gene set enrichment analysis showed a positive enrichment of pathways associated with the immune response, cell viability, proliferation, and cellular movement. Moreover, pathways involved in implantation, embryo development, oocyte maturation, and angiogenesis were positively enriched. The differential gene expression analysis, after adjusting for multiple testing, showed no significantly differentially expressed genes between the two groups. A comparative analysis was also performed with similar studies conducted in other animals or in vitro using human endometrial cells. The comparative analysis showed that the effect of seminal plasma effect on the endometrium is similar in pigs, mice, and in vitro human endometrial cells. The present study provides evidence that seminal plasma might impact the endometrium during the implantation window, with potential to affect endometrial receptivity and embryo development.

Exercise Induction of Key Transcriptional Regulators of Metabolic Adaptation in Muscle Is Preserved in Type 2 Diabetes.

CONTEXT: Type 2 diabetes (T2D) is characterized by insulin resistance in skeletal muscle. Regular exercise improves insulin sensitivity, mitochondrial function, and energy metabolism. Thus, an impaired response to exercise may contribute to insulin resistance. OBJECTIVE: We hypothesized that key transcriptional regulators of metabolic adaptation to exercise show an attenuated response in skeletal muscle in T2D. DESIGN AND PATIENTS: Skeletal muscle biopsies were obtained from 13 patients with T2D and 14 age- and weight-matched controls before, immediately after 1 hour acute exercise (70% maximal pulmonary oxygen uptake), and 3 hours into recovery to examine mRNA expression of key transcription factors and downstream targets and activity of key upstream kinases underlying the metabolic adaptation to exercise. RESULTS: Acute exercise increased gene expression of the nuclear hormone receptor 4A (NR4A) subfamily (∼4- to 36-fold) and other key transcription factors, including ATF3, EGR1, JUNB, SIK1, PPARA, and PPARG (∼1.5- to 12-fold), but with no differences between groups. The expression of NR4A1 (approximately eightfold) and NR4A3 (∼75-fold) was further increased 3 hours into recovery, whereas most muscle transcripts sustained elevated or returned to basal levels, again with no differences between groups. Muscle expression of HKII and SLC2A4 and hexokinase II protein content were reduced in patients with T2D. The phosphorylation of p38 MAPK, Erk1/2, Ca2+/calmodulin-dependent kinase II, and cAMP-responsive element-binding protein was equally increased in response to exercise and/or recovery in both groups. CONCLUSION: Acute exercise elicits a pronounced and overall similar increase in expression of key transcription factors and activation of key upstream kinases involved in muscle metabolic adaptation to exercise in patients with T2D and weight-matched controls.

MESP1 knock-down in human iPSC attenuates early vascular progenitor cell differentiation after completed primitive streak specification.

MESP1 is a key transcription factor in development of early cardiovascular tissue and it is required for induction of the cardiomyocyte (CM) gene expression program, but its role in vascular development is unclear. Here, we used inducible CRISPRi knock-down of MESP1 to analyze the molecular processes of the early differentiation stages of human induced pluripotent stem cells into mesoderm and subsequently vascular progenitor cells. We found that expression of the mesodermal marker, BRACHYURY (encoded by T) was unaffected in MESP1 knock-down cells as compared to wild type cells suggesting timely movement through the primitive streak whereas another mesodermal marker MIXL1 was slightly, but significantly decreased. In contrast, the expression of the vascular cell surface marker KDR was decreased and CD31 and CD34 expression were substantially reduced in MESP1 knock-down cells supporting inhibition or delay of vascular specification. In addition, mRNA microarray data revealed several other altered gene expressions including the EMT regulating transcription factors SNAI1 and TWIST1, which were both significantly decreased indicating that MESP1 knock-down cells are less likely to undergo EMT during vascular progenitor differentiation. Our study demonstrates that while leaving primitive streak markers unaffected, MESP1 expression is required for timely vascular progenitor specification. Thus, MESP1 expression is essential for the molecular features of early CM, EC and VSMC lineage specification.

Human induced pluripotent stem cell-derived vascular smooth muscle cells: differentiation and therapeutic potential.

Cardiovascular diseases remain the leading cause of death worldwide and current treatment strategies have limited effect of disease progression. It would be desirable to have better models to study developmental and pathological processes and model vascular diseases in laboratory settings. To this end, human induced pluripotent stem cells (hiPSCs) have generated great enthusiasm, and have been a driving force for development of novel strategies in drug discovery and regenerative cell-therapy for the last decade. Hence, investigating the mechanisms underlying the differentiation of hiPSCs into specialized cell types such as cardiomyocytes, endothelial cells, and vascular smooth muscle cells (VSMCs) may lead to a better understanding of developmental cardiovascular processes and potentiate progress of safe autologous regenerative therapies in pathological conditions. In this review, we summarize the latest trends on differentiation protocols of hiPSC-derived VSMCs and their potential application in vascular research and regenerative therapy.

CRISPR Interference Efficiently Induces Specific and Reversible Gene Silencing in Human iPSCs.

Developing technologies for efficient and scalable disruption of gene expression will provide powerful tools for studying gene function, developmental pathways, and disease mechanisms. Here, we develop clustered regularly interspaced short palindromic repeat interference (CRISPRi) to repress gene expression in human induced pluripotent stem cells (iPSCs). CRISPRi, in which a doxycycline-inducible deactivated Cas9 is fused to a KRAB repression domain, can specifically and reversibly inhibit gene expression in iPSCs and iPSC-derived cardiac progenitors, cardiomyocytes, and T lymphocytes. This gene repression system is tunable and has the potential to silence single alleles. Compared with CRISPR nuclease (CRISPRn), CRISPRi gene repression is more efficient and homogenous across cell populations. The CRISPRi system in iPSCs provides a powerful platform to perform genome-scale screens in a wide range of iPSC-derived cell types, dissect developmental pathways, and model disease.

The microRNA-132/212 family fine-tunes multiple targets in Angiotensin II signalling in cardiac fibroblasts.

INTRODUCTION: MicroRNAs (miRNAs) are emerging as key regulators of cardiovascular development and disease; however, the cardiac miRNA target molecules are not well understood. We and others have described the Angiotensin II (AngII)-induced miR-132/212 family as novel regulators of cardiovascular function including regulation of cardiac hypertrophy, heart failure and blood pressure possibly through AT1R signalling. However, the miR-132/212 targets in the heart remain unknown. MATERIALS AND METHODS: To understand the role of these miRNAs in cardiac signalling networks, we undertook comprehensive in silico and in vitro experiments to identify miR-132/212 molecular targets in primary rat cardiac fibroblasts. RESULTS: MiR-132/212 overexpression increased fibroblast cell size and mRNA arrays detected several hundred genes that were differentially expressed, including a wide panel of receptors, signalling molecules and transcription factors. Subsequent comprehensive in silico analysis identified 24 target genes, of which 22 genes were qPCR validated. We identified seven genes involved in AngII signalling pathways. CONCLUSION: We here report novel insight of an extensive network of molecular pathways that fine-tuned by miR-132/212, suggesting a role for this miRNA family as master signalling switches in cardiac fibroblasts. Our data underscore the potential for miRNA tools to manipulate a large array of molecules and thereby control biological function.

The 14q32 microRNA-487b targets the antiapoptotic insulin receptor substrate 1 in hypertension-induced remodeling of the aorta.

OBJECTIVES: To study the role of microRNAs in hypertension-induced vascular pathology before the onset of symptoms of severe cardiovascular disease. BACKGROUND: MicroRNAs play a crucial role in cardiovascular disease. However, microRNAs are often studied in full-blown cardiovascular disease models, not during development of cardiovascular pathology. METHODS: Angiotensin II was infused into healthy adult rats, inducing chronic hypertension, and microRNA expression profiles were obtained. The most prominently regulated microRNA, miR-487b, was further investigated, using primary cultures of rat aortic and human umbilical cord arterial cells. RESULTS: MiR-487b is predicted to target insulin receptor substrate 1 (IRS1). IRS1 plays an important role in both insulin signaling and cell proliferation and survival. IRS1 mRNA and protein levels were downregulated in aortae of hypertensive rats. MiR-487b binds directly to both rat and human IRS1 3'UTR and inhibits reporter gene expression in vitro. In primary rat and human arterial adventitial fibroblasts, inhibition of miR-487b leads to upregulation of IRS1 expression. Upregulation of miR-487b had the opposite effect, confirming direct targeting of IRS1 by miR-487b.Immunohistochemistry of aortic cross sections and rt/qPCR analyses of the separate aortic wall layers showed that both IRS1 and miR-487b were present mainly in the adventitia and less or not at all in the intima and tunica media. IRS1 expression in adventitial fibroblasts was predominantly nuclear and nuclear IRS1 is known to have antiapoptotic effects. Indeed, inhibition of miR-487b protected adventitial fibroblasts, and also medial smooth muscle cells, against serum starvation-induced apoptosis and increased cell survival. CONCLUSIONS: Angiotensin II-induced hypertension leads to upregulation of miR-487b, which targets IRS1. Via downregulation of IRS1, miR-487b can contribute to cell death and loss of adventitial and medial integrity during hypertension-induced vascular pathology.

Angiotensin II regulates microRNA-132/-212 in hypertensive rats and humans.

MicroRNAs (miRNAs), a group of small non-coding RNAs that fine tune translation of multiple target mRNAs, are emerging as key regulators in cardiovascular development and disease. MiRNAs are involved in cardiac hypertrophy, heart failure and remodeling following cardiac infarction; however, miRNAs involved in hypertension have not been thoroughly investigated. We have recently reported that specific miRNAs play an integral role in Angiotensin II receptor (AT1R) signaling, especially after activation of the Gαq signaling pathway. Since AT1R blockers are widely used to treat hypertension, we undertook a detailed analysis of potential miRNAs involved in Angiotensin II (AngII) mediated hypertension in rats and hypertensive patients, using miRNA microarray and qPCR analysis. The miR-132 and miR-212 are highly increased in the heart, aortic wall and kidney of rats with hypertension (159 ± 12 mm Hg) and cardiac hypertrophy following chronic AngII infusion. In addition, activation of the endothelin receptor, another Gαq coupled receptor, also increased miR-132 and miR-212. We sought to extend these observations using human samples by reasoning that AT1R blockers may decrease miR-132 and miR-212. We analyzed tissue samples of mammary artery obtained from surplus arterial tissue after coronary bypass operations. Indeed, we found a decrease in expression levels of miR-132 and miR-212 in human arteries from bypass-operated patients treated with AT1R blockers, whereas treatment with ß-blockers had no effect. Taken together, these data suggest that miR-132 and miR-212 are involved in AngII induced hypertension, providing a new perspective in hypertensive disease mechanisms.