To the extent possible under law, AOP-Wiki has waived all copyright and related or neighboring rights to KE:298
Key Event Title
|Level of Biological Organization|
Key Event Components
Key Event Overview
AOPs Including This Key Event
|AOP Name||Role of event in AOP||Point of Contact||Author Status||OECD Status|
|Developmental Vascular Toxicity||KeyEvent||Tom Knudsen (send email)||Open for citation & comment||EAGMST Under Review|
Key Event Description
Embryonic blood vessels form in a reproducible pattern that interfaces with other embryonic structures and tissues [Hogan et al. 2004]. Many human diseases, including stroke, retinopathy, and cancer, are associated with the vascular biology, including endothelial cells and pericytes that establish the blood-brain barrier and control cerebrovascular exchanges [Bautch and James, 2009; Eichmann and Thomas, 2013; Saili et al. 2017]. Functionally, blood vessel morphogenesis is critical for providing oxygen, nutrients and molecular signals to developing tissues [Maltepe et al. 1997; Vargesson, 2003; Chung and Ferrara, 2011; Eshkar-Oren et al. 2015]. The developing vascular network is shaped into a hierarchical system of arteries and veins, through progressive effects on blood vessel arborization (microvasculature) and pruning (angio-adaptation) [Jin et al. 2017]. The former is morpho-regulatory whereas the reshaping is influenced by regional changes in blood flow and local metabolic demands [Tran et al. 2007]. Evidence supports the ability of physiological parameters such as oxygen and glucose concentrations to affect the expression of genes critical for developmental angiogenesis [Maltepe and Simon, 1998]. Growth in tissue mass during organogenesis is thought to lead to the formation of hypoxic/nutrient-deprived cells. The subsequent activation of sensors such as HIF-1 [Xia et al. 2009; Oladipupo et al. 2011; Li et al. 2018] and ARNT [Maltepe et al. 1997; Abbott and Buckalew, 2000] that rapidly trans-activate the expression of genes such as VEGF that drive angiogenesis.
While mammalian embryos become sensitive to hypoxia during early organogenesis, the small size of zebrafish embryos renders this species less vulnerable to hypoxia than vertebrate counterparts; however, the genetic control of microvascular development is conserved among vertebrate species as evidenced by hypoxia-responsive signaling (HIF-1) via local oxygen-sensing gradients in the zebrafish, chick and mouse embryo [Hogan et al. 2004; Liu et al. 2017; Gerri et al. 2017]. The neural tube, for example, provides vascular patterning signals that direct formation of the perineural vascular plexus (PNVP) that encompasses the neural tube at mid-gestation [Hogan et al. 2004]. This process is temporally and spatially associated with Vegfa expression as the neural tube signal through VEGFR-2. Mesodermal VEGFR-2 expression is localized to the lateral portion of the somite and later to sclerotomal cells surrounding the neural tube under the positive control of BMP4 signaling and negative control by Noggin, a BMP4 antagonist [Nimmagadda et al. 2005]. Reciprocal signaling between VEGF-induced endothelial cells and neuroprogenitor cells enhanced formation of the brain neurovascular unit [Vissapragada et al. 2014]. In transgenic zebrafish embryos, the VEGFR-2 antagonist, Vatalanib produced a direct concentration-dependent progression of impaired intersegmental vessel (ISV) outgrowth in early embryos, increased rates of malformed hatched larva, and reduced survival in juvenile cohorts [Tal et al. 2014]. These data show that disruption in the early embryo has a lasting impact on advanced life stages.
Another key cell sensing activity is the recruitment of macrophage (microglia?) cells that secrete pro-angiogenic cytokines and proteases, remodeling the extracellular matrix (ECM) and providing survival and guidance cues to endothelial cells [Gerri et al. 2017]. Macrophages play crucial roles at each step of the angiogenic cycle, from sprouting to maturation and remodelling of the vascular plexus through angiopoietin-TIE2 signaling [Du Cheyne et al. 2020], which is known to synergize with the VEGF-pathway during developmental angiogenesis [Li et al. 2014]. A seminal study showed that loss of immature blood vessels is the primary cause of Thalidomide-induced teratogenesis in the chick embryo, where anti-angiogenic but not anti-inflammatory analogues of Thalidomide induced limb reduction defects. Outgrowth and remodeling of more mature blood vessels delayed, whereas newly formed angiogenic vessels were lost prior to limb dysmorphogenesis and altered patterns of gene expression [Therapontos et al. 2009; Vargesson, 2015]. Vascular insufficiency is likely important in human embryos where the window of vulnerability to Thalidomide-induced phocomelia precedes full establishment of the adult arterial pattern by the 8th week of gestation [Hootnick et al. 2016; Hootnick et al. 2017; Vargesson and Hootnick, 2017].
As such, a chemical’s potential to disrupt vascular patterning and/or remodeling during organogenesis can have profound effects on many systems, including: early limb development [Beedie et al. 2016a, 2016b, 2017 and 2020]; neurovascular development [Hogan et al. 2004; Hallene et al. 2006; Bautch and James, 2009; Eichman and Thomas, 2013; Vissapragada et al. 2014; Fiorentino et al. 2016; Uwamori et al. 2017; Huang, 2020]; and utero-placental development [Abbott and Buckalew, 2000; Douglas et al. 2009; Rutland et al. 2009; Chen, 2014; Araujo et al. 2021].
How It Is Measured or Detected
Complex functional assays such as the rat aortic explant assay, rat whole embryo culture, and the zebrafish embryotoxicity along with transcriptomic signatures provide a tiered approach to evaluate HTS signatures and their taxonomic implications for conserved pathways to prioritize further in vivo testing studies [Ellis-Hutchings et al. 2017].
Zebrafish reporter assays: Blood flow begins in the zebrafish embryo at ∼24 h postfertilization. Shortly after this, the angiogenic vessels that perfuse the trunk of the embryo (intersegmental vessels) sprout from the vasculogenic vessels [Tran et al. 2007]. These effects can be visualized in automated, quantitative screening assays using transgenic zebrafish expressing green fluorescent protein (GFP) under the control of the vascular endothelial growth factor receptor (VEGFR) Vegfr2 promoter that restricts reporter gene expression to developing blood vessels. Phenotypic readouts have been used to screen and validate anti-angiogenic compounds [Tran et al. 2007; Yano et al. 2012; Yozzo et al. 2013; Tal et al. 2014; McCollum et al. 2017]. Live-cell imaging has been used to quantitatively detect the trajectory dynamics of vascular patterning [Clendenon et al. 2013; Shirinfard et al. 2013] and confocal cell imaging has been used to develop a quantitative assay capable of detecting relatively subtle changes (~8%) in relative to controls during chemical exposure [Tal et al. 2017].
ToxCast: A study evaluated two anti-angiogenic agents, 5HPP-33, a synthetic Thalidomide analog [Noguchi et al. 2005] and TNP-470, a synthetic Fumagillan analog [Ingber et al. 1990] across the ToxCast HTS assay platform and anchored the results to complex in vitro functional assays: the rat aortic explant assay, rat whole embryo culture, and zebrafish embryotoxicity [Saili et al. 2019]. Both compounds disrupted angiogenesis and embryogenesis in the functional assays, with differences in potency and adverse effects. 5HPP-33 was embryolethal, whereas TNP-470 produced caudal defects at low concentrations [Ellis-Hutchings et al. 2017]. Anti-angiogenic modes of action are known for 5HPP-33, which blocks tubulin polymerization inhibition [Yeh et al. 2000; Inatsuki et al. 2005; Kizaki et al. 2008; Rashid et al. 2015); and TNP-470, a methionine aminopeptidase II (MetAP2) inhibition, through non-canonical Wnt inhibition of endothelial proliferation [Ingber et al. 1990]. Transcriptomic profiles of exposed embryos pathways unique to each and in common to both, strongest being the TP53 pathway [Saili et al. 2019]. In mouse, TNP-470 reduced fetal intraocular microvasculature and induced microphthalmia, either directly or via effects on placental morphology [Rutland et al. 2009].
Computational models: Critical pathways for developmental angiogenesis and potential disruptions have critical signal-response systems embedded in three types of receptors that play key roles in a number of morphoregulatory processes: receptor tyrosine kinases (e.g., growth factor-signaling), G-protein coupled receptors (e.g., chemokine signaling), and GPI-anchored receptors (e.g., uPAR system). Computational approaches have been used to predict vascular insufficiency for potential vascular disrupting chemicals (pVDCs) that are developmental toxicants or non-toxicants [Kleinstreuer et al. 2011; Knudsen and Kleinstreuer, 2011]. This has been applied to the ToxCast inventory to rank order over a thousand chemicals for validation testing [McCollum et al. 2017; Tal et al. 2017; Saili et al. 2019; Zurlinden et al. 2020].
Domain of Applicability
Complex functional assays such as the rat aortic explant assay (AEA), rat whole embryo culture (WEC), and the zebrafish embryotoxicity (ZET) along with transcriptomic signatures provide a tiered approach to evaluate HTS signatures and their taxonomic implications for conserved pathways to prioritize further in vivo testing studies [Ellis-Hutchings et al. 2017].
Abbott, B. D. and Buckalew, A. R. (2000). Placental defects in arnt-knockout conceptus correlate with localized decreases in vegf-r2, ang-1, and tie-2. Developmental dynamics : an official publication of the American Association of Anatomists 219, 526-538. doi:10.1002/1097-0177(2000)9999:9999<::AID-DVDY1080>3.0.CO;2-N. PMID:11084652
Araujo Júnior, E., Zamarian, A. C., Caetano, A. C. et al. (2021). Physiopathology of late-onset fetal growth restriction. Minerva obstetrics and gynecology 73, 392-408. doi:10.23736/S2724-606X.21.04771-7. PMID:33876907
Bautch, V. L. and James, J. M. (2009). Neurovascular development: The beginning of a beautiful friendship. Cell adhesion & migration 3, 199-204. doi:10.4161/cam.3.2.8397. PMID:19363295
Beedie, S. L., Mahony, C., Walker, H. M. et al. (2016). Shared mechanism of teratogenicity of anti-angiogenic drugs identified in the chicken embryo model. Scientific reports 6, 30038-30038. doi:10.1038/srep30038. PMID:27443489
Beedie, S. L., Rore, H. M., Barnett, S. et al. (2016). In vivo screening and discovery of novel candidate thalidomide analogs in the zebrafish embryo and chicken embryo model systems. Oncotarget 7, 33237-33245. doi:10.18632/oncotarget.8909. PMID:27120781
Beedie, S. L., Diamond, A. J., Fraga, L. R. et al. (2017). Vertebrate embryos as tools for anti-angiogenic drug screening and function. Reproductive toxicology (Elmsford, N.Y.) 70, 49-59. doi:10.1016/j.reprotox.2016.11.013. PMID:27888069
Beedie, S. L., Huang, P. A., Harris, E. M. et al. (2020). Role of cereblon in angiogenesis and in mediating the antiangiogenic activity of immunomodulatory drugs. FASEB journal : official publication of the Federation of American Societies for Experimental Biology 34, 11395-11404. doi:10.1096/fj.201903060RR. PMID:32677118
Chen, D. B. and Zheng, J. (2014). Regulation of placental angiogenesis. Microcirculation (New York, N.Y. : 1994) 21, 15-25. doi:10.1111/micc.12093. PMID:23981199
Chung, A. S. and Ferrara, N. (2011). Developmental and pathological angiogenesis. Annual review of cell and developmental biology 27, 563-584. doi:10.1146/annurev-cellbio-092910-154002. PMID:21756109
Douglas, N. C., Tang, H., Gomez, R. et al. (2009). Vascular endothelial growth factor receptor 2 (vegfr-2) functions to promote uterine decidual angiogenesis during early pregnancy in the mouse. Endocrinology 150, 3845-3854. doi:10.1210/en.2008-1207. PMID:19406950
Du Cheyne, C., Tay, H. and De Spiegelaere, W. (2020). The complex tie between macrophages and angiogenesis. Anatomia, histologia, embryologia 49, 585-596. doi:10.1111/ahe.12518. PMID:31774212
Eichmann, A. and Thomas, J. L. (2013). Molecular parallels between neural and vascular development. Cold Spring Harbor perspectives in medicine 3, a006551-a006551. doi:10.1101/cshperspect.a006551. PMID:23024177
Ellis-Hutchings, R. G., Settivari, R. S., McCoy, A. T. et al. (2017). Embryonic vascular disruption adverse outcomes: Linking high throughput signaling signatures with functional consequences. Reproductive toxicology (Elmsford, N.Y.) 70, 82-96. doi:10.1016/j.reprotox.2017.05.005. PMID:28527947
Eshkar-Oren, I., Krief, S., Ferrara, N. et al. (2015). Vascular patterning regulates interdigital cell death by a ros-mediated mechanism. Development (Cambridge, England) 142, 672-680. doi:10.1242/dev.120279. PMID:25617432
Fiorentino, M., Sapone, A., Senger, S. et al. (2016). Blood-brain barrier and intestinal epithelial barrier alterations in autism spectrum disorders. Molecular autism 7, 49-49. doi:10.1186/s13229-016-0110-z. PMID:27957319
Gerri, C., Marín-Juez, R., Marass, M. et al. (2017). Hif-1a regulates macrophage-endothelial interactions during blood vessel development in zebrafish. Nature communications 8, 15492-15492. doi:10.1038/ncomms15492. PMID:28524872
Hallene, K. L., Oby, E., Lee, B. J. et al. (2006). Prenatal exposure to thalidomide, altered vasculogenesis, and cns malformations. Neuroscience 142, 267-283. doi:10.1016/j.neuroscience.2006.06.017. PMID:16859833
Hogan, K. A., Ambler, C. A., Chapman, D. L. et al. (2004). The neural tube patterns vessels developmentally using the vegf signaling pathway. Development (Cambridge, England) 131, 1503-1513. doi:10.1242/dev.01039. PMID:14998923
Hootnick, D. R., DeSesso, J. M. and Vargesson, N. (2016). Congenital embryonic arterial and skeletal dysgeneses. Radiographics : a review publication of the Radiological Society of North America, Inc 36, 1257-1257. doi:10.1148/rg.2016150243. PMID:27399246
Hootnick, D. R., Vargesson, N. and Birch, J. (2017). Regarding a limb with pffd, fibular dimelia and mirror foot deformity. Journal of pediatric orthopedics. Part B 26, 589-589. doi:10.1097/BPB.0000000000000490. PMID:28945698
Huang, H. (2020). Pericyte-endothelial interactions in the retinal microvasculature. International journal of molecular sciences 21, doi:10.3390/ijms21197413. PMID:33049983
Inatsuki, S., Noguchi, T., Miyachi, H. et al. (2005). Tubulin-polymerization inhibitors derived from thalidomide. Bioorganic & medicinal chemistry letters 15, 321-325. doi:10.1016/j.bmcl.2004.10.072. PMID:15603947
Ingber, D., Fujita, T., Kishimoto, S. et al. (1990). Synthetic analogues of fumagillin that inhibit angiogenesis and suppress tumour growth. Nature 348, 555-557. doi:10.1038/348555a0. PMID:1701033
Jin, D., Zhu, D., Fang, Y. et al. (2017). Vegfa signaling regulates diverse artery/vein formation in vertebrate vasculatures. Journal of genetics and genomics = Yi chuan xue bao 44, 483-492. doi:10.1016/j.jgg.2017.07.005. PMID:29037991
Kizaki, M. and Hashimoto, Y. (2008). New tubulin polymerization inhibitor derived from thalidomide: Implications for anti-myeloma therapy. Current medicinal chemistry 15, 754-765. doi:10.2174/092986708783955473. PMID:18393844
Kleinstreuer, N. C., Judson, R. S., Reif, D. M. et al. (2011). Environmental impact on vascular development predicted by high-throughput screening. Environmental health perspectives 119, 1596-1603. doi:10.1289/ehp.1103412. PMID:21788198
Knudsen, T. B. and Kleinstreuer, N. C. (2011). Disruption of embryonic vascular development in predictive toxicology. Birth defects research. Part C, Embryo today : reviews 93, 312-323. doi:10.1002/bdrc.20223. PMID:22271680
Li, S., Hsu, C. W., Sakamuru, S. et al. (2018). Identification of angiogenesis inhibitors using a co-culture cell model in a high-content and high-throughput screening platform. SLAS technology 23, 217-225. doi:10.1177/2472630317729792. PMID:28922619
Li, W., Chen, J., Deng, M. et al. (2014). The zebrafish tie2 signaling controls tip cell behaviors and acts synergistically with vegf pathway in developmental angiogenesis. Acta biochimica et biophysica Sinica 46, 641-646. doi:10.1093/abbs/gmu055. PMID:25001479
Liu, H., Yang, Q., Radhakrishnan, K. et al. (2009). Role of vegf and tissue hypoxia in patterning of neural and vascular cells recruited to the embryonic heart. Developmental dynamics : an official publication of the American Association of Anatomists 238, 2760-2769. doi:10.1002/dvdy.22103. PMID:19842184
Maltepe, E., Schmidt, J. V., Baunoch, D. et al. (1997). Abnormal angiogenesis and responses to glucose and oxygen deprivation in mice lacking the protein arnt. Nature 386, 403-407. doi:10.1038/386403a0. PMID:9121557
Maltepe, E. and Simon, M. C. (1998). Oxygen, genes, and development: An analysis of the role of hypoxic gene regulation during murine vascular development. Journal of molecular medicine (Berlin, Germany) 76, 391-401. doi:10.1007/s001090050231. PMID:9625296
McCollum, C. W., Conde-Vancells, J., Hans, C. et al. (2017). Identification of vascular disruptor compounds by analysis in zebrafish embryos and mouse embryonic endothelial cells. Reproductive toxicology (Elmsford, N.Y.) 70, 60-69. doi:10.1016/j.reprotox.2016.11.005. PMID:27838387
Nimmagadda, S., Geetha Loganathan, P., Huang, R. et al. (2005). Bmp4 and noggin control embryonic blood vessel formation by antagonistic regulation of vegfr-2 (quek1) expression. Developmental biology 280, 100-110. doi:10.1016/j.ydbio.2005.01.005. PMID:15766751
Noguchi, T., Fujimoto, H., Sano, H. et al. (2005). Angiogenesis inhibitors derived from thalidomide. Bioorganic & medicinal chemistry letters 15, 5509-5513. doi:10.1016/j.bmcl.2005.08.086. PMID:16183272
Oladipupo, S., Hu, S., Kovalski, J. et al. (2011). Vegf is essential for hypoxia-inducible factor-mediated neovascularization but dispensable for endothelial sprouting. Proceedings of the National Academy of Sciences of the United States of America 108, 13264-13269. doi:10.1073/pnas.1101321108. PMID:21784979
Rashid, A., Kuppa, A., Kunwar, A. et al. (2015). Thalidomide (5hpp-33) suppresses microtubule dynamics and depolymerizes the microtubule network by binding at the vinblastine binding site on tubulin. Biochemistry 54, 2149-2159. doi:10.1021/bi501429j. PMID:25747795
Rutland, C. S., Jiang, K., Soff, G. A. et al. (2009). Maternal administration of anti-angiogenic agents, tnp-470 and angiostatin4.5, induces fetal microphthalmia. Molecular vision 15, 1260-1269. PMID:19572040
Saili, K. S., Zurlinden, T. J., Schwab, A. J. et al. (2017). Blood-brain barrier development: Systems modeling and predictive toxicology. Birth defects research 109, 1680-1710. doi:10.1002/bdr2.1180. PMID:29251840
Saili, K. S., Franzosa, J. A., Baker, N. C. et al. (2019). Systems modeling of developmental vascular toxicity. Current opinion in toxicology 15, 55-63. doi:10.1016/j.cotox.2019.04.004. PMID:32030360
Tal, T., Kilty, C., Smith, A. et al. (2017). Screening for angiogenic inhibitors in zebrafish to evaluate a predictive model for developmental vascular toxicity. Reproductive toxicology (Elmsford, N.Y.) 70, 70-81. doi:10.1016/j.reprotox.2016.12.004. PMID:28007540
Tal, T. L., McCollum, C. W., Harris, P. S. et al. (2014). Immediate and long-term consequences of vascular toxicity during zebrafish development. Reproductive toxicology (Elmsford, N.Y.) 48, 51-61. doi:10.1016/j.reprotox.2014.05.014. PMID:24907688
Therapontos, C., Erskine, L., Gardner, E. R. et al. (2009). Thalidomide induces limb defects by preventing angiogenic outgrowth during early limb formation. Proceedings of the National Academy of Sciences of the United States of America 106, 8573-8578. doi:10.1073/pnas.0901505106. PMID:19433787
Tran, T. C., Sneed, B., Haider, J. et al. (2007). Automated, quantitative screening assay for antiangiogenic compounds using transgenic zebrafish. Cancer research 67, 11386-11392. doi:10.1158/0008-5472.CAN-07-3126. PMID:18056466
Uwamori, H., Higuchi, T., Arai, K. et al. (2017). Integration of neurogenesis and angiogenesis models for constructing a neurovascular tissue. Scientific reports 7, 17349-17349. doi:10.1038/s41598-017-17411-0. PMID:29229920
Vargesson, N. (2003). Vascularization of the developing chick limb bud: Role of the tgfbeta signalling pathway. Journal of anatomy 202, 93-103. doi:10.1046/j.1469-7580.2003.00133.x. PMID:12587924
Vargesson, N. (2015). Thalidomide-induced teratogenesis: History and mechanisms. Birth defects research. Part C, Embryo today : reviews 105, 140-156. doi:10.1002/bdrc.21096. PMID:26043938
Vissapragada, R., Contreras, M. A., da Silva, C. G. et al. (2014). Bidirectional crosstalk between periventricular endothelial cells and neural progenitor cells promotes the formation of a neurovascular unit. Brain research 1565, 44425-44425. doi:10.1016/j.brainres.2014.03.018. PMID:24675025
Xia, M., Bi, K., Huang, R. et al. (2009). Identification of small molecule compounds that inhibit the hif-1 signaling pathway. Molecular cancer 8, 117-117. doi:10.1186/1476-4598-8-117. PMID:20003191
Yano, S., Matsumori, Y., Ikuta, K. et al. (2006). Current status and perspective of angiogenesis and antivascular therapeutic strategy: Non-small cell lung cancer. Int J Clin Oncol 11, 73-81. doi:10.1007/s10147-006-0568-3. PMID:16622742
Yeh, J. R., Mohan, R. and Crews, C. M. (2000). The antiangiogenic agent tnp-470 requires p53 and p21cip/waf for endothelial cell growth arrest. Proceedings of the National Academy of Sciences of the United States of America 97, 12782-12787. doi:10.1073/pnas.97.23.12782. PMID:11070090
Yozzo, K. L., Isales, G. M., Raftery, T. D. et al. (2013). High-content screening assay for identification of chemicals impacting cardiovascular function in zebrafish embryos. Environmental science & technology 47, 11302-11310. doi:10.1021/es403360y. PMID:24015875
Zurlinden, T. J., Saili, K. S., Baker, N. C. et al. (2020). A cross-platform approach to characterize and screen potential neurovascular unit toxicants. Reproductive toxicology (Elmsford, N.Y.) 96, 300-315. doi:10.1016/j.reprotox.2020.06.010. PMID:32590145