scholarly journals Establishment of a Bernard-Soulier syndrome model in zebrafish

Haematologica ◽  
2021 ◽  
Author(s):  
Qing Lin ◽  
Riyang Zhou ◽  
Panpan Meng ◽  
Liangliang Wu ◽  
Lian Yang ◽  
...  
Keyword(s):  
Animal Model ◽  
Strategy Development ◽  
Functional Assay ◽  
Bleeding Tendency ◽  
Zebrafish Model ◽  
Uncertain Significance ◽  
Clinical Drugs ◽  
Underlying Mechanisms ◽  
Bernard Soulier Syndrome

Platelets play an essential role in thrombosis and hemostasis. Abnormal hemostasis can cause spontaneous or severe post-traumatic bleeding. Bernard-Soulier syndrome (BSS) is a rare inherited bleeding disorder caused by a complete quantitative deficiency in the GPIb-IX-V complex. Multiple mutations in GP9 lead to the clinical manifestation of BSS. Understanding the roles and underlying mechanisms of GP9 in thrombopoiesis and establishing a proper animal model of BSS would be valuable to understand the disease pathogenesis and to improve its medical management. Here, by using CRISPR-Cas9 technology, we created a zebrafish gp9SMU15 mutant to model human BSS. Disruption of zebrafish gp9 led to thrombocytopenia and a high bleeding tendency, as well as an abnormal expansion of progenitor cells. The gp9SMU15 zebrafish can be used as a BSS animal model as GP9 roles in thrombocytopoiesis are highly conserved from zebrafish to mammals. Utilizing the BSS model, we verified the clinical GP9 mutations by in vivo functional assay and tested clinical drugs for increasing platelets. Thus, the inherited BSS zebrafish model could be of benefit for in vivo verification of patient-derived GP9 variants of uncertain significance and for potential BSS therapeutic strategy development.

scholarly journals Perturbations of BMP/TGF-β and VEGF/VEGFR signalling pathways in non-syndromic sporadic brain arteriovenous malformations (BAVM)

2018 ◽  
Vol 55 (10) ◽  
pp. 675-684 ◽  
Author(s):  
Kun Wang ◽  
Sen Zhao ◽  
Bowen Liu ◽  
Qianqian Zhang ◽  
Yaqi Li ◽  
...  
Keyword(s):  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Arteriovenous Malformations ◽  
Transforming Growth Factor ◽  
Transgenic Zebrafish ◽  
Zebrafish Model ◽  
Brain Arteriovenous Malformations ◽  
Pathogenic Variants ◽  
Uncertain Significance

BackgroundBrain arteriovenous malformations (BAVM) represent a congenital anomaly of the cerebral vessels with a prevalence of 10–18/100 000. BAVM is the leading aetiology of intracranial haemorrhage in children. Our objective was to identify gene variants potentially contributing to disease and to better define the molecular aetiology underlying non-syndromic sporadic BAVM.MethodsWe performed whole-exome trio sequencing of 100 unrelated families with a clinically uniform BAVM phenotype. Pathogenic variants were then studied in vivo using a transgenic zebrafish model.ResultsWe identified four pathogenic heterozygous variants in four patients, including one in the established BAVM-related gene, ENG, and three damaging variants in novel candidate genes: PITPNM3, SARS and LEMD3, which we then functionally validated in zebrafish. In addition, eight likely pathogenic heterozygous variants (TIMP3, SCUBE2, MAP4K4, CDH2, IL17RD, PREX2, ZFYVE16 and EGFR) were identified in eight patients, and 16 patients carried one or more variants of uncertain significance. Potential oligogenic inheritance (MAP4K4 with ENG, RASA1 with TIMP3 and SCUBE2 with ENG) was identified in three patients. Regulation of sma- and mad-related proteins (SMADs) (involved in bone morphogenic protein (BMP)/transforming growth factor beta (TGF-β) signalling) and vascular endothelial growth factor (VEGF)/vascular endotheliual growth factor recepter 2 (VEGFR2) binding and activity (affecting the VEGF signalling pathway) were the most significantly affected biological process involved in the pathogenesis of BAVM.ConclusionsOur study highlights the specific role of BMP/TGF-β and VEGF/VEGFR signalling in the aetiology of BAVM and the efficiency of intensive parallel sequencing in the challenging context of genetically heterogeneous paradigm.

scholarly journals Interpreting TMEM67 missense variants of uncertain significance (VUS) in an animal model

2021 ◽  
Author(s):  
Karen I Lange ◽  
Sunayna Best ◽  
Sofia Tsiropoulou ◽  
Ian Berry ◽  
Colin A Johnson ◽  
...  
Keyword(s):  
Animal Model ◽  
Molecular Genetic ◽  
Genetic Diagnosis ◽  
Knock Out ◽  
Variants Of Uncertain Significance ◽  
C Elegans ◽  
In Vivo Animal Model ◽  
Uncertain Significance

Purpose: A molecular genetic diagnosis is essential for accurate counselling and management of patients with ciliopathies. Uncharacterized missense alleles are often classified as variants of uncertain significance (VUS) and are not clinically useful. In this study, we explore the use of a tractable animal model (C. elegans) for in vivo interpretation of missense VUS alleles of TMEM67, a gene frequently mutated as a cause of ciliopathies. Methods: CRISPR/Cas9 gene editing was used to generate homozygous worm strains carrying TMEM67 patient variants. Quantitative phenotypic assays (dye filling, roaming, chemotaxis) assessed cilia structure and function. Results were validated by genetic complementation assays in a human TMEM67 knock-out hTERT-RPE1 cell line. Results: Quantitative assays in C. elegans distinguished between known benign (Asp359Glu, Thr360Ala) and pathogenic (Glu361Ter, Gln376Pro) variants. Analysis of seven missense VUS alleles predicted two benign (Cys173Arg, Thr176Ile) and four pathogenic variants (Cys170Tyr, His782Arg, Gly786Glu, His790Arg). Results from one VUS (Gly979Arg) were inconclusive in worms, but additional in vitro validation suggested it was likely benign. Conclusion: Efficient genome editing and quantitative functional assays in C. elegans make it a tractable in vivo animal model that allows stratification and rapid, cost-effective interpretation of ciliopathy-associated missense VUS alleles.

scholarly journals Zebrafish-Based Screening Models for the Identification of Anti-Metastatic Drugs

Molecules ◽  
2020 ◽  
Vol 25 (10) ◽  
pp. 2407
Author(s):  
Joji Nakayama ◽  
Hideki Makinoshima
Keyword(s):  
Animal Model ◽  
Drug Discovery ◽  
Cancer Cells ◽  
High Throughput Screening ◽  
Metastatic Tumor ◽  
Tumor Formation ◽  
Zebrafish Model ◽  
Step Process ◽  
Physiological Relevance

Metastasis, a leading contributor to the morbidity of cancer patients, occurs through a multi-step process: invasion, intravasation, extravasation, colonization, and metastatic tumor formation. Each process is not only promoted by cancer cells themselves but is also affected by their microenvironment. Given this complexity, drug discovery for anti-metastatic drugs must consider the interaction between cancer cells and their microenvironments. The zebrafish is a suitable vertebrate animal model for in vivo high-throughput screening studies with physiological relevance to humans. This review covers the zebrafish model used to identify anti-metastatic drugs.

scholarly journals Clofazimine: A Promising Inhibitor of Rabies Virus

2021 ◽  
Vol 12 ◽  
Author(s):  
Jiajing Wu ◽  
Shouchun Cao ◽  
Shan Lei ◽  
Qiang Liu ◽  
Yinghong Li ◽  
...  
Keyword(s):  
Rabies Virus ◽  
High Throughput Screening ◽  
Survival Rates ◽  
Positive Control ◽  
Post Exposure Prophylaxis ◽  
Antiviral Therapies ◽  
Clinical Drugs ◽  
Underlying Mechanisms ◽  
Exposure Prophylaxis

With an almost 100% mortality rate, rabies virus (RABV) infection is a global concern. Limited post-exposure prophylaxis and lack of an effective treatment necessitate novel antiviral therapies against RABV. Here, using a high-throughput screening (HTS) method developed in our lab, 11 candidates with anti-RABV activity were identified from a library of 767 clinical drugs. Clofazimine (CFZ), an anti-leprosy drug, displayed an EC50 of 2.28 μM, and SI over 967 against RABV. Investigations into the underlying mechanisms revealed that CFZ targeted viral membrane fusion at the early stages of virus replication. Moreover, CFZ and Clofazimine salicylates (CFZS) exhibited elevated survival rates in vivo, compared with the positive control T-705. Thus, this study revealed CFZ as a promising drug against RABV infection.

scholarly journals Remediation of ABCG5-Linked Macrothrombocytopenia With Ezetimibe Therapy

2021 ◽  
Vol 12 ◽  
Author(s):  
Libin Deng ◽  
Jingsong Xu ◽  
Wei Chen ◽  
Shicheng Guo ◽  
Robert D. Steiner ◽  
...  
Keyword(s):  
Compound Heterozygous ◽  
Bleeding Tendency ◽  
Platelet Size ◽  
Ezetimibe Treatment ◽  
Large Platelet ◽  
Uncertain Significance ◽  
Complete Blood Counts

To investigate refractory hypercholesterolemia, a female patient and relatives were subjected to whole-genome sequencing. The proband was found to have compound heterozygous substitutions p. Arg446Gln and c.1118+3G>T in ABCG5, one of two genes causing sitosterolemia. When tracing these variants in the full pedigree, all maternally related heterozygotes for the intronic ABCG5 variant exhibited large platelets (over 30 fl), which segregated in an autosomal dominant manner, consistent with macrothrombocytopenia, or large platelet syndrome which may be associated with a bleeding tendency. In vitro cell-line and in vivo rat model experiments supported a pathogenic role for the variant and the macrothrombocytopenia was recapitulated in heterozygous rats and human cell lines exhibiting that single variant. Ezetimibe treatment successfully ameliorated all the symptoms of the proband with sitosterolemia and resolved the macrothrombocytopenia of the treated heterozygote relatives. Subsequently, in follow up these observations, platelet size, and size distribution were measured in 1,180 individuals; 30 were found to be clinically abnormal, three of which carried a single known pathogenic ABCG5 variant (p.Arg446Ter) and two individuals carried novel ABCG5 variants of uncertain significance. In this study, we discovered that identification of large platelets and therefore a possible macrothrombocytopenia diagnosis could easily be inadvertently missed in clinical practice due to variable instrument settings. These findings suggest that ABCG5 heterozygosity may cause macrothrombocytopenia, that Ezetimibe treatment may resolve macrothrombocytopenia in such individuals, and that increased attention to platelet size on complete blood counts can aid in the identification of candidates for ABCG5 genetic testing who might benefit from Ezetimibe treatment.

scholarly journals Variation in wall shear stress in channel networks of zebrafish models

2017 ◽  
Vol 14 (127) ◽  
pp. 20160900 ◽  
Author(s):  
Woorak Choi ◽  
Hye Mi Kim ◽  
Sungho Park ◽  
Eunseop Yeom ◽  
Junsang Doh ◽  
...  
Keyword(s):  
Animal Model ◽  
Shear Stress ◽  
Wall Shear Stress ◽  
Blood Vessels ◽  
Equivalent Circuit Model ◽  
Zebrafish Model ◽  
Typical Application ◽  
Wall Shear

Physiological functions of vascular endothelial cells (ECs) vary depending on wall shear stress (WSS) magnitude, and the functional change affects the pathologies of various cardiovascular systems. Several in vitro and in vivo models have been used to investigate the functions of ECs under different WSS conditions. However, these models have technical limitations in precisely mimicking the physiological environments of ECs and monitoring temporal variations of ECs in detail. Although zebrafish ( Danio rerio ) has several strategies to overcome these technical limitations, zebrafish cannot be used as a perfect animal model because applying various WSS conditions on blood vessels of zebrafish is difficult. This study proposes a new zebrafish model in which various WSS can be applied to the caudal vein. The WSS magnitude is controlled by blocking some parts of blood-vessel networks. The accuracy and reproducibility of the proposed method are validated using an equivalent circuit model of blood vessels in zebrafish. The proposed method is applied to lipopolysaccharide (LPS)-stimulated zebrafish as a typical application. The proposed zebrafish model can be used as an in vivo animal model to investigate the relationship between WSS and EC physiology or WSS-induced cardiovascular diseases.

scholarly journals MITO-Luc/GFP zebrafish model to assess spatial and temporal evolution of cell proliferation in vivo

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Luisa de Latouliere ◽  
Isabella Manni ◽  
Laura Ferrari ◽  
Federica Pisati ◽  
Maria Grazia Totaro ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Animal Model ◽  
Temporal Evolution ◽  
Luciferase Activity ◽  
Luciferase Expression ◽  
Transgenic Zebrafish ◽  
X Rays ◽  
Adult Zebrafish ◽  
Zebrafish Model

AbstractWe developed a novel reporter transgenic zebrafish model called MITO-Luc/GFP zebrafish in which GFP and luciferase expression are under the control of the master regulator of proliferation NF-Y. In MITO-Luc/GFP zebrafish it is possible to visualize cell proliferation in vivo by fluorescence and bioluminescence. In this animal model, GFP and luciferase expression occur in early living embryos, becoming tissue specific in juvenile and adult zebrafish. By in vitro and ex vivo experiments we demonstrate that luciferase activity in adult animals occurs in intestine, kidney and gonads, where detectable proliferating cells are located. Further, by time lapse experiments in live embryos, we observed a wave of GFP positive cells following fin clip. In adult zebrafish, in addition to a bright bioluminescence signal on the regenerating tail, an early unexpected signal coming from the kidney occurs indicating not only a fin cell proliferation, but also a systemic response to tissue damage. Finally, we observed that luciferase activity was inhibited by anti-proliferative interventions, i.e. 5FU, cell cycle inhibitors and X-Rays. In conclusion, MITO-Luc/GFP zebrafish is a novel animal model that may be crucial to assess the spatial and temporal evolution of cell proliferation in vivo.

scholarly journals Generation of a double binary transgenic zebrafish model to study myeloid gene regulation in response to melanocyte transformation

2017 ◽  
Author(s):  
Amy Kenyon ◽  
Daria Gavriouchkina ◽  
Giorgio Napolitani ◽  
Vincenzo Cerundolo ◽  
Tatjana Sauka-Spengler
Keyword(s):  
Immune Response ◽  
Cancer Cells ◽  
Cell Transformation ◽  
Transcriptional Profiling ◽  
Cathepsin L ◽  
Transgenic Zebrafish ◽  
Zebrafish Model ◽  
Galectin 3 ◽  
Underlying Mechanisms

ABSTRACTA complex network of inflammation succeeds somatic cell transformation and malignant disease. Immune cells and their associated molecules are responsible for detecting and eliminating cancer cells as they establish themselves as the precursors of a tumour. By the time a patient has a detectable solid tumour, cancer cells have escaped the initial immune response mechanisms. To date, no model exists for studying the underlying mechanisms that govern the initial phase of the immune response when transformed cells become precursors of cancer. Here we describe the development of a double binary zebrafish model designed for exploring regulatory programming of the myeloid cells as they respond to oncogenic transformed melanocytes. A hormone-inducible binary system allows for temporal control of different Ras-oncogenes (NRasK61Q, HRasG12V, KRasG12V) expression in melanocytes, enabling analysis of melanocyte transformation and melanoma initiation. This model was coupled to binary cell-specific biotagging models allowing in vivo biotinylation and subsequent isolation of macrophage or neutrophil nuclei for regulatory profiling of their active transcriptomes. Nuclear transcriptional profiling of neutrophils, performed for the first time as they respond to the earliest precursors of melanoma in vivo, revealed an intricate landscape of regulatory factors that may promote progression to melanoma including fgf1, fgf6, cathepsin H, cathepsin L, galectin 1 and galectin 3. The model presented here provides a powerful platform to study the myeloid response to the earliest precursors of melanoma.Summary StatementWe present an innovative double binary zebrafish model for exploring the underlying regulatory mechanisms that govern the myeloid response mechanisms at the onset of melanoma.

scholarly journals Developing Tadpole Xenopus laevis as a Comparative Animal Model to Study Mycobacterium abscessus Pathogenicity

2021 ◽  
Vol 22 (2) ◽  
pp. 806
Author(s):  
Arianna Lopez ◽  
Carolyn Shoen ◽  
Michael Cynamon ◽  
Dionysia Dimitrakopoulou ◽  
Matthieu Paiola ◽  
...  
Keyword(s):  
Animal Model ◽  
Xenopus Laevis ◽  
Pulmonary Infection ◽  
Bacterial Load ◽  
Mycobacterium Abscessus ◽  
Zebrafish Model ◽  
Experimental Organism ◽  
Immunocompetent Mice ◽  
Significant Mortality

Mycobacterium abscessus (Mab) is an emerging, nontuberculosis mycobacterium (NTM) that infects humans. Mab has two morphotypes, smooth (S) and rough (R), related to the production of glycopeptidolipid (GPL), that differ in pathogenesis. To further understand the pathogenicity of these morphotypes in vivo, the amphibian Xenopus laevis was used as an alternative animal model. Mab infections have been previously modeled in zebrafish embryos and mice, but Mab are cleared early from immunocompetent mice, preventing the study of chronic infection, and the zebrafish model cannot be used to model a pulmonary infection and T cell involvement. Here, we show that X. laevis tadpoles, which have lungs and T cells, can be used as a complementary model for persistent Mab infection and pathogenesis. Intraperitoneal (IP) inoculation of S and R Mab morphotypes disseminated to tadpole tissues including liver and lungs, persisting for up to 40 days without significant mortality. Furthermore, the R morphotype was more persistent, maintaining a higher bacterial load at 40 days postinoculation. In contrast, the intracardiac (IC) inoculation with S Mab induced significantly greater mortality than inoculation with the R Mab form. These data suggest that X. laevis tadpoles can serve as a useful comparative experimental organism to investigate pathogenesis and host resistance to M. abscessus.

scholarly journals Baicalein 5,6-Dimethyl Ether Prevents Memory Deficits in the Scopolamine Zebrafish Model by Regulating Cholinergic and Antioxidant Systems

Plants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1245
Author(s):  
Ion Brinza ◽  
Iriny M. Ayoub ◽  
Omayma A. Eldahshan ◽  
Lucian Hritcu
Keyword(s):  
Oxidative Stress ◽  
Dimethyl Ether ◽  
Exploratory Behavior ◽  
Memory Performance ◽  
Memory Deficits ◽  
Antioxidant Systems ◽  
Zebrafish Model ◽  
Brain Oxidative Stress ◽  
Underlying Mechanisms

Baicalein 5,6-dimethyl ether, a bioactive flavonoid isolated for the first time from Alnus rugosa, was explored for its capability to relieve memory deficits and decrease oxidative stress. We examined the neuropharmacological effects of baicalein 5,6-dimethyl ether on scopolamine (Sco)-induced zebrafish (Danio rerio) anxiety, amnesia, and brain oxidative stress and attempted to elucidate the underlying mechanisms. Anxiety-like behavior, exploratory behavior, and memory performance were measured using novel tank-diving test (NTT), Y-maze, and novel object recognition (NOR) tests. For 10 days, baicalein 5,6-dimethyl ether (1, 3, and 5 µg/L) was administered through immersion, whereas Sco (100 μM) was delivered 30 min before behavioral tests. Treatment with baicalein 5,6-dimethyl ether reduced anxiety and memory impairment, and increased exploratory behavior in specific tests, along with significant protection from neuronal oxidative stress in the brain tissue of Sco-treated zebrafish. Antioxidant and anti-acetylcholinesterase (AChE) activities of baicalein 5,6-dimethyl ether in the Sco-induced zebrafish were further confirmed using in vivo assays. In Sco-treated zebrafish, baicalein 5,6-dimethyl ether regulated cholinergic function by inhibiting AChE activity. Baicalein 5,6-dimethyl ether may be a promising candidate compound for treating anxiety and amnesia by restoring cholinergic activity and reducing brain oxidative stress, according to our findings.

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