Transgenic Expression of A Venous Malformation Related Mutation, TIE2-R849W, Significantly Induces Multiple Malformations of Zebrafish

Bisphenol S induces cardiovascular toxicity by disturbing the development of the common cardinal vein and myocardial contractility in zebrafish embryos

Bisphenol S (BPS) has been widely used as a substitute for bisphenol A in industrial manufacturing. However, the safety of BPS is controversial, and the mechanism by which BPS exerts cardiovascular toxicity remains unclear. In this study, zebrafish embryos, including wild-type zebrafish and transgenic (flk1:eGFP), (gata1:DsRed) and (cmlc2:eGFP) zebrafish at 2 h postfertilization (hpf), were exposed to BPS at concentrations of 1, 10 and 100 μg/L for 24, 48 and 72 h, respectively. The data showed that BPS accelerated the expansion of the common cardinal vein and inhibited lumen formation between 24 hpf and 72 hpf. Moreover, low-dose BPS disturbed cardiac muscle contraction by breaking the calcium balance in cardiac muscle cells according to the RNA-seq results. As a consequence, increased heart rate and irregular blood circulation were observed in the BPS treatment groups. This result suggested that BPS at environmental relevant concentrations caused cardiovascular toxicity during the development of zebrafish embryos, possibly being an important inducer of cardiovascular injury later in life. These findings provide insight into the rational and safe application of BPS.

Cerebral cavernous malformations do not fall in the spectrum of PIK3CA-related overgrowth

Somatic gain-of-function (GOF) mutations in phosphatidylinositol-4, 5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), the catalytic subunit of phosphoinositide 3-kinase (PI3K), have been recently discovered in cerebral cavernous malformations (CCMs), raising the possibility that the activation of PI3K pathways is a possible universal regulator of vascular morphogenesis. However, there have been contradicting data presented among various groups and studies. To enhance the current understanding of vascular anomalies, it is essential to explore this possible relationship between altered PI3K signalling pathways and its influence on the pathogenesis of CCMs. GOF PIK3CA-mutants have been linked to overgrowth syndromes, allowing this group of disorders, resulting from somatic activating mutations in PIK3CA, to be collectively named as PIK3CA-related overgrowth spectrum disorders. This paper reviews and attempts to conceptualise the relationships and differences among clinical presentations, genotypic and phenotypic correlations and possible coexistence of PIK3CA and CCM mutations/phenotypes in CCM lesions. Finally, we present a model reflecting our hypothetical understanding of CCM pathogenesis based on a systematic review and conceptualisation of data obtained from other studies.

Application of zebrafish in the study of craniomaxillofacial developmental anomalies

Craniomaxillofacial developmental anomalies are one of the most prevalent congenital defects worldwide and could result from any disruption of normal development processes, which is generally influenced by interactions between genes and the environment. Currently, with the advances in genetic screening strategies, an increasing number of novel variants and their roles in orofacial diseases have been explored. Zebrafish is recognized as a powerful animal model, and its homologous genes and similar oral structure and development process provide an ideal platform for studying the contributions of genetic and environmental factors to human craniofacial malformations. Here, we reviewed zebrafish models for the study of craniomaxillofacial developmental anomalies, such as human nonsyndromic cleft lip with or without an affected palate and jaw and tooth developmental anomalies. Due to its potential for gene expression and regulation research, zebrafish may provide new perspectives for understanding craniomaxillofacial diseaseand its treatment.

A Xenograft Model for Venous Malformation

Xenograft models allow for an in vivo approach to monitor cellular functions within the context of a host microenvironment. Here we describe a protocol to generate a xenograft model of venous malformation (VM) based on the use of human umbilical vein endothelial cells (HUVEC) expressing a constitutive active form of the endothelial tyrosine kinase receptor TEK (TIE2 p.L914F) or patient-derived EC containing TIE2 and/or PIK3CA gene mutations. Hyperactive somatic TIE2 and PIK3CA mutations are a common hallmark of VM in patient lesions. The EC are injected subcutaneously on the back of athymic nude mice to generate ectatic vascular channels and recapitulate histopathological features of VM patient tissue histology. Lesion plugs with TIE2/PIK3CA-mutant EC are visibly vascularized within 7-9 days of subcutaneous injection, making this a great tool to study venous malformation.

High-throughput transcriptional profiling combined with angiogenesis antibody array analysis in an orbital venous malformation cohort

Orbital venous malformations (OVMs) are the most common benign orbital vascular disorders in adults and are characterized as enlarging encapsulated vascular neoplasms. These painless lesions grow slowly and become symptomatic with proptosis or visual disturbance. However, the pathogenic mechanism and diagnostic markers of OVMs remain poorly understood. To identify potential pathways involved in OVM formation, a cDNA microarray analysis was conducted with OVM samples and normal vascular tissues. These data were deposited in the National Omics Data Encyclopedia (NODE) database (accession number: OER033009). These pathway expression data were further confirmed by reverse transcription qPCR (RT-qPCR) in an OVM cohort. To explore the diagnostic markers in OVM, an angiogenesis antibody array was analyzed. The altered factors were further validated by enzyme-linked immunosorbent assay (ELISA) in the OVM cohort. Transcriptome screening revealed upregulated autophagy and VEGF pathways and downregulated Hippo, Wnt, hedgehog and vascular smooth muscle contraction signaling pathways in OVM samples. Furthermore, plasma EGF (p < 0.001) and Leptin (p < 0.01) levels were significantly elevated in OVM patients. Here, for the first time, we revealed the transcriptional background and plasma diagnostic markers in OVM, providing a novel understanding of OVM pathogenesis and facilitating the early diagnosis of OVM.

Monitoring antiangiogenesis of bevacizumab in zebrafish

Bevacizumab, which is a humanized anti-VEGF antibody, has been successfully applied in clinics since 2004. Bevacizumab in combination with chemotherapy showed high safety and has been applied to solid tumors. However, studies on the insight into the mechanism about the antiangiogenesis activity of bevacizumab were mostly done on mice models, and so there are no visual and intuitive models to observe the process of antiangiogenesis. Here, we first used a zebrafish model to investigate the angiogenesis suppressing behavior of bevacizumab. Our results showed that bevacizumab inhibited formation of zebrafish subintestinal veins, which mimics the process of tumor angiogenesis in vivo. Meanwhile, bevacizumab caused specific vasculature formation defects in subintestinal veins but not in the trunk. Our study also indicated that bevacizumab could inhibit zebrafish retinal angiogenesis with therapeutic potential.