A crucial role of caldesmon in vascular development in vivo.
ABSTRACT We explored the in vivo effects of knockdown of caldesmon on vascular development in zebrafish.
We investigated the effects of caldesmon knockdown on the vascular development in a zebrafish model with special attention for the trunk and head vessels including the aortic arches. We examined the developing fishes at various time points. The vascular abnormalities observed in the caldesmon morphants were morphologically and functionally characterized in detail in fixed and living embryos. The knockdown of caldesmon caused serious defects in vasculogenesis and angiogenesis in zebrafish morphants, and the vascular integrity and blood circulation were concomitantly impaired.
The data provide the first functional assessment of the role of caldesmon in vascular development in vivo, indicating that this molecule plays a crucial role in vasculogenesis and angiogenesis in vivo. Interfering with caldesmon opens new therapeutic avenues for anti-angiogenesis in cancer and ischaemic cardiovascular disease.
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ABSTRACT: Trimethyltin chloride (TMT) is an organotin contaminant, widely detected in aqueous environments, posing potential human and environmental risks. In this study, we utilized the zebrafish model to investigate the impact of transient TMT exposure on developmental progression, angiogenesis, and cardiovascular development. Embryos were waterborne exposed to a wide TMT concentration range from 8 to 96 h post fertilization (hpf). The TMT concentration that led to mortality in 50% of the embryos (LC50) at 96 hpf was 8.2 μM; malformations in 50% of the embryos (EC50) was 2.8 μM. The predominant response observed in surviving embryos was pericardial edema. Additionally, using the Tg (fli1a: EGFP) y1 transgenic zebrafish line to non-invasively monitor vascular development, TMT exposure led to distinct disarrangements in the vascular system. The most susceptible developmental stage to TMT exposure was between 48 and 72 hpf. High density whole genome microarrays were used to identify the early transcriptional changes following TMT exposure from 48 to 60 hpf or 72 hpf. In total, 459 transcripts were differentially expressed at least 2-fold (P < 0.05) by TMT compared to control. Using Ingenuity Pathway Analysis (IPA) tools, it was revealed that the transcripts misregulated by TMT exposure were clustered in numerous categories including metabolic and cardiovascular disease, cellular function, cell death, molecular transport, and physiological development. In situ localization of highly elevated transcripts revealed intense staining of ADP-ribosylation factors arf3 and arf5 in the head, trunk, and tail regions. When arf5 expression was blocked by morpholinos, the zebrafish did not display the prototypical TMT-induced vascular deficits, indicating that the induction of arf5 was necessary for TMT-induced vascular toxicity.Toxicology 12/2012; 302(s 2–3):129–139. · 4.02 Impact Factor
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ABSTRACT: There are various zebrafish models with cardiovascular defects which adequately mimic the impaired circulation and tissue perfusion of various human cardiovascular diseases. Zebrafish embryos/larvae are optically transparent, and the systemic blood circulation can be recorded by using a microscope with video imaging. We detected a series of circulatory defects in our caldesmon and glucose transport 1 knockdown zebrafish models, including arteriovenous (AV) shunting, collateral circulation, AV fusion, vessel bifurcation, reduced or depleted regional perfusion, sinus venous (SV) rupture, and more. The quick detection by simple video imaging of various pathological states of the blood circulation in the living zebrafish embryos/larvae is non-invasive and cost-effective. The method is suitable for large scale screening of altered blood circulation in various zebrafish models with impaired cardiovascular development. This is a powerful approach of live digital data communication in biomedical research and teaching.08/2013;
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ABSTRACT: Glioblastoma (GB) displays diffusely infiltrative growth patterns. Dispersive cells escape surgical resection and contribute to tumor recurrence within a few centimeters of the resection cavity in 90% of cases. We know that the non-neoplastic stromal compartment, in addition to infiltrative tumor cells, plays an active role in tumor recurrence. We isolated a new stromal cell population from the histologically normal surgical margins of GB by computer-guided stereotaxic biopsies and primary culture. These GB-associated stromal cells (GASCs) share phenotypic and functional properties with the cancer-associated fibroblasts (CAFs) described in the stroma of carcinomas. In particular, GASCs have tumor-promoting effects on glioma cells in vitro and in vivo. Here, we describe a quantitative proteomic analysis using iTRAQ labeling and mass spectrometry to compare GASCs with control stromal cells derived from non-GB peripheral brain tissues. A total of 1077 proteins were quantified and 67 proteins were found to differ between GASCs and control stromal cells. Several proteins changed in GASCs are related to a highly motile myofibroblast phenotype, and to wound healing and angiogenesis. The results for several selected proteins were validated by western blotting or flow cytometry. Furthermore, the effect of GASCs on angiogenesis was confirmed with the orthotopic U87MG glioma model. In conclusion, GASCs, isolated from GB histologically normal surgical margins and found mostly near blood vessels are a vascular niche constituent establishing a permissive environment facilitating angiogenesis and possibly colonization of recurrence-initiating cells. We identify various proteins as being expressed in GASCs: some of these proteins may serve as prognostic factors for GB and/or targets for anti-glioma treatment.The Journal of Pathology 01/2014; · 7.59 Impact Factor