scholarly journals The effect of absent blood flow on the zebrafish cerebral and trunk vasculature

2021 ◽  
Author(s):  
Elisabeth Kugler ◽  
Ryan Snodgrass ◽  
George Bowley ◽  
Karen Plant ◽  
Jovana Serbanovic-Canic ◽  
...  

The role of blood flow in vascular development is complex and context-dependent. In this study, we quantify the effect of the lack of blood flow on embryonic vascular development on two vascular beds, namely the cerebral and trunk vasculature in zebrafish. We perform this by analysing vascular topology, endothelial cell (EC) number, EC distribution, apoptosis, and inflammatory response in animals with normal blood flow or absent blood flow. We find that absent blood flow reduced vascular area and endothelial cell number significantly in both examined vascular beds, but the effect is more severe in the cerebral vasculature, and severity increases over time. Absent blood flow leads to an increase in non-EC-specific apoptosis without increasing tissue inflammation, as quantified by cerebral immune cell numbers and nitric oxide. Similarly, while stereotypic vascular patterning in the trunk is maintained, intra-cerebral vessels show altered patterning, which is likely to be due to vessels failing to initiate effective fusion and anastomosis rather than sprouting or path-seeking. In conclusion, blood flow is essential for cellular survival in both the trunk and cerebral vasculature, but particularly intra-cerebral vessels are affected by the lack of blood flow, suggesting that responses to blood flow differ between these two vascular beds.

2020 ◽  
Author(s):  
Elisabeth Kugler ◽  
Ryan Snodgrass ◽  
George Bowley ◽  
Karen Plant ◽  
Jovana Serbanovic-Canic ◽  
...  

AbstractThe role of blood flow is complex and context-dependent. In this study, we quantify the effect of the lack of blood flow on vascular development and compare its impact in two vascular beds, namely the cerebral and trunk vasculature, using zebrafish as preclinical model. We performed this by analysing vascular topology, endothelial cell number, apoptosis, and inflammatory response in animals with normal blood flow or absent blood flow. We find that absent blood flow reduced vascular area and endothelial cell number significantly in both examined vascular beds, but the effect is more severe in the cerebral vasculature. Similarly, while stereotypic vascular patterning in the trunk is maintained, intra-cerebral vessels show altered patterning. Absent blood flow lead to an increase in non-EC-specific apoptosis without increasing tissue inflammation, as quantified by cerebral immune cell numbers and nitric oxide. In conclusion, blood flow is essential for cellular survival in both the trunk and cerebral vasculature, but particularly intra-cerebral vessels are affected by the lack of blood flow, suggesting that responses to blood flow differ between these two vascular beds.Key pointsWe here use zebrafish as a model to quantitatively assess the impact of the lack of blood flow in development and compare its impact in two vascular beds, namely the cerebral to trunk vasculature.In both vascular beds, vascular growth and endothelial cell number are reduced by lack of blood flow, with increasing effect size from 2-5 days post fertilisation.Examination of vascular patterning shows that while stereotypic patterning in the trunk is preserved, the intra-cerebral vasculature patterning is altered.We found non-EC-specific cell death to be increased in both vascular beds, with a larger effect size in the brain, but that this cell death occurs without triggering tissue inflammation.


1982 ◽  
Vol 242 (5) ◽  
pp. R441-R446 ◽  
Author(s):  
A. L. Lopez de Pablo ◽  
M. C. Gonzalez ◽  
G. Dieguez ◽  
B. Gomez ◽  
S. Lluch

The effects on cerebral blood flow of alpha- or beta-adrenergic receptor stimulation of cerebral vessels were examined in 13 unanesthetized goats before and during hypercapnia produced by inhalation of 10% CO2 in air. This procedure increased the PCO2 from 34 to 52 and was accompanied by a fall in pH from 7.39 to 7.26. Electrical stimulation of the cervical sympathetic nerve and injections of norepinephrine and tyramine into the internal maxillary artery produced reductions in cerebral blood flow that were abolished or reduced in hypercapnia. The increase in cerebral blood flow in response to beta-adrenergic stimulation with isoproterenol was also reduced. Hypercapnia caused a similar depression of the constrictor and dilatory effects of the nonadrenergic drugs vasopressin and diazoxide. The results show a decreased response of cerebral vessels to adrenergic and nonadrenergic stimuli in hypercapnia. The findings do not suggest any difference between the refractoriness of cerebral vessels in hypercapnia and that described in other vascular beds.


2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 178-179
Author(s):  
S. Alehashemi ◽  
M. Garg ◽  
B. Sellers ◽  
A. De Jesus ◽  
A. Biancotto ◽  
...  

Background:Systemic Autoinflammatory diseases present with sterile inflammation. NOMID (Neonatal-Onset Multisystem Inflammatory Disease) is caused by gain-of-function mutations inNLRP3and excess IL-1 production, presents with fever, neutrophilic dermatosis, aseptic meningitis, hearing loss and eye inflammation; CANDLE (Chronic Atypical Neutrophilic Dermatosis, Lipodystrophy and Elevated Temperature) is caused by loss-of-function mutations in proteasome genes that lead to type-1 interferon signaling, characterized by fever, panniculitis, lipodystrophy, cytopenia, systemic and pulmonary hypertension and basal ganglia calcification. IL-1 blockers are approved for NOMID and JAK-inhibitors show efficacy in CANDLE treatment.Objectives:We used proteomic analysis to compare differentially expressed proteins in active NOMID and CANDLE compared to healthy controls before and after treatment, and whole blood bulk RNA seq to identify the immune cell signatures.Methods:Serum samples from active NOMID (n=12) and CANDLE (n=7) before and after treatment (table 1) and age matched healthy controls (HC) (n=7) were profiled using the SomaLogic platform (n=1125 proteins). Differentially expressed proteins in NOMID and CANDLE were ranked after non-parametric tests for unpaired (NOMIDp<0.05, CANDLE,p<0.1) and paired (p<0.05) analysis and assessed by enriched Gene Ontology pathways and network visualization. Whole blood RNA seq was performed (NOMID=7, CANDLE=7, Controls =5) and RPKM values were used to assess immune cells signatures.Table 1.Patient’s characteristicsNOMIDN=12, Male =6CANDLEN=7, Male =6AgeMedian (range)12 (2, 28)16 (3, 20)Ethnicity%White (Hispanic)80 (20)100 (30)GeneticsNLRP3mutation(2 Somatic, 10 Germline)mutations in proteasome component genes(1 digenic, 6 Homozygous/compound Heterozygous)Before treatmentAfter treatmentBefore treatmentAfter treatmentCRPMedian (range) mg/L52 (16-110)5 (0-23)5 (0-101)1 (0-4)IFN scoremedian (range)0NA328 (211-1135)3 (0-548)Results:Compared to control, 205 proteins (127 upregulated, 78 downregulated) were significantly different at baseline in NOMID, compared to 163 proteins (101 upregulated, and 62 downregulated) in CANDLE. 134 dysregulated proteins (85 upregulated, 49 downregulated) overlapped in NOMID and CANDLE (Figure 1). Pathway analysis identified neutrophil and monocyte chemotaxis signature in both NOMID and CANDLE. NOMID patients had neutrophilia and active neutrophils. CANDLE patients exhibited active neutrophils in whole blood RNA. Endothelial cell activation was the most prominent non-hematopoietic signature and suggest distinct endothelial cell dysregulation in NOMID and CANDLE. In NOMID, the signature included neutrophil transmigration (SELE) endothelial cell motility in response to angiogenesis (HGF, VEGF), while in CANDLE the endothelial signatures included extracellular matrix protein deposition (COL8A) suggesting increased vascular stiffness. CANDLE patients had higher expression of Renin, 4 out of 7 had hypertension, NOMID patients did not have hypertension. Treatment with anakinra and baricitinib normalized 143 and 142 of dysregulated proteins in NOMID and CANDLE respectively.Conclusion:Differentially expressed proteins in NOMID and CANDLE are consistent with innate immune cell activation. Distinct endothelial cell signatures in NOMID and CANDLE may provide mechanistic insight into differences in vascular phenotypes. Treatment with anakinra and Baricitinib in NOMID and CANDLE leaves 30% and 13% of the dysregulated proteins unchanged.Acknowledgments:This work was supported by Intramural Research atNational Institute of Allergy Immunology and Infectious Diseases of National Institutes of Health, Bethesda, Maryland, the Center of Human Immunology and was approved by the IRB.Disclosure of Interests:None declared


2021 ◽  
pp. 1-9
Author(s):  
Rima Dardik ◽  
Ophira Salomon

Intracranial hemorrhage (ICH) associated with fetal/neonatal alloimmune thrombocytopenia (FNAIT) is attributed mainly to endothelial damage caused by binding of maternal anti-HPA-1a antibodies to the αvβ3 integrin on endothelial cells (ECs). We examined the effect of anti-HPA-1a antibodies on EC function using 2 EC lines from different vascular beds, HMVEC of dermal origin and hCMEC/D3 of cerebral origin. Anti-HPA-1a sera significantly increased apoptosis in both HMVEC and hCMEC/D3 cells and permeability in hCMEC/D3 cells only. This increase in both apoptosis and permeability was significantly inhibited by a monoclonal anti-β3 antibody (SZ21) binding to the HPA-1a epitope. Our results indicate that (1) maternal anti-HPA-1a antibodies impair EC function by increasing apoptosis and permeability and (2) ECs from different vascular beds vary in their susceptibility to pathological effects elicited by maternal anti-HPA-1a antibodies on EC permeability. Examination of maternal anti-HPA-1a antibodies for their effect on EC permeability may predict potential ICH associated with FNAIT.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Simon Chewchuk ◽  
Sanzida Jahan ◽  
David Lohnes

AbstractThe intestinal epithelium is a unique tissue, serving both as a barrier against pathogens and to conduct the end digestion and adsorption of nutrients. As regards the former, the intestinal epithelium contains a diverse repertoire of immune cells, including a variety of resident lymphocytes, macrophages and dendritic cells. These cells serve a number of roles including mitigation of infection and to stimulate regeneration in response to damage. The transcription factor Cdx2, and to a lesser extent Cdx1, plays essential roles in intestinal homeostasis, and acts as a context-dependent tumour suppressor in colorectal cancer. Deletion of Cdx2 from the murine intestinal epithelium leads to macrophage infiltration resulting in a chronic inflammatory response. However the mechanisms by which Cdx2 loss evokes this response are poorly understood. To better understand this relationship, we used a conditional mouse model lacking all intestinal Cdx function to identify potential target genes which may contribute to this inflammatory phenotype. One such candidate encodes the histocompatability complex protein H2-T3, which functions to regulate intestinal iCD8α lymphocyte activity. We found that Cdx2 occupies the H3-T3 promoter in vivo and directly regulates its expression via a Cdx response element. Loss of Cdx function leads to a rapid and pronounced attenuation of H2-T3, followed by a decrease in iCD8α cell number, an increase in macrophage infiltration and activation of pro-inflammatory cascades. These findings suggest a previously unrecognized role for Cdx in intestinal homeostasis through H2-T3-dependent regulation of iCD8α cells.


3 Biotech ◽  
2021 ◽  
Vol 11 (11) ◽  
Author(s):  
Xiaohan Yang ◽  
Xinyue Shen ◽  
Zhujun Li ◽  
Wencai Li ◽  
Ying Liu

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