Bioengineered in vitro Vascular Models for Applications in Interventional Radiology

2019 ◽  
Vol 24 (45) ◽  
pp. 5367-5374 ◽  
Author(s):  
Xiaoyun Li ◽  
Seyed M. Moosavi-Basri ◽  
Rahul Sheth ◽  
Xiaoying Wang ◽  
Yu S. Zhang

The role of endovascular interventions has progressed rapidly over the past several decades. While animal models have long-served as the mainstay for the advancement of this field, the use of in vitro models has become increasingly widely adopted with recent advances in engineering technologies. Here, we review the strategies, mainly including bioprinting and microfabrication, which allow for fabrication of biomimetic vascular models that will potentially serve to supplement the conventional animal models for convenient investigations of endovascular interventions. Besides normal blood vessels, those in diseased states, such as thrombosis, may also be modeled by integrating cues that simulate the microenvironment of vascular disorders. These novel engineering strategies for the development of biomimetic in vitro vascular structures will possibly enable unconventional means of studying complex endovascular intervention problems that are otherwise hard to address using existing models.

PPAR Research ◽  
2008 ◽  
Vol 2008 ◽  
pp. 1-13 ◽  
Author(s):  
Y. Lynn Wang ◽  
Qi Miao

The role of PPARγin tumorigenesis is controversial. In this article, we review and analyze literature from the past decade that highlights the potential proneoplastic activity of PPARγ. We discuss the following five aspects of the nuclear hormone receptor and its agonists: (1) relative expression of PPARγin human tumorversusnormal tissues; (2) receptor-dependent proneoplastic effects; (3) impact of PPARγand its agonists on tumors in animal models; (4) clinical trials of thiazolidinediones (TZDs) in human malignancies; (5) TZDs as chemopreventive agents in epidemiology studies. The focus is placed on the most relevantin vivoanimal models and human data.In vitrocell line studies are included only when the effects are shown to be dependent on the PPARγreceptor.


Physiology ◽  
1990 ◽  
Vol 5 (2) ◽  
pp. 75-79
Author(s):  
R Montesano ◽  
M Pepper ◽  
L Orci

Angiogenesis, the formation of new capillary blood vessels, plays a crucial role in a variety of physiological and pathological processes but until recently could only be studied in animal models. Newly developed in vitro models of angiogenesis provide an opportunity for experimental dissection of molecular mechanisms of neovascularization.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Elieser Hitoshi Watanabe ◽  
Fernando Morbeck Almeida Coelho ◽  
Hilton Leão Filho ◽  
Bruno Eduardo Pedroso Balbo ◽  
Precil Diego Miranda de Menezes Neves ◽  
...  

AbstractRenal angiomyolipomas hemorrhage is associated with their size and vascular constitution. The effects of sirolimus on different components of angiomyolipomas was analyzed in patients with tuberous sclerosis complex, sporadic lymphangioleiomyomatosis and multiple sporadic angiomyolipomas. Thirty angiomyolipomas from 14 patients treated with sirolimus were retrospectively evaluated. A Hounsfield-unit threshold was used to classify angiomyolipomas in fat-rich, fat-poor and intermediate-fat tumors, and to categorize tumor compartments in fat rich, fat poor, intermediate fat and highly vascularized. Diameter variations were measured to assess the effects on aneurysmatic/ectatic vascular formations. Volume reduction following treatment with sirolimus was higher in fat-poor than fat-rich angiomyolipomas. Tumor reduction was mainly determined by decrease of the fat-poor and highly-vascularized compartments while the volume of the fat-rich compartment increased. Broad liposubstitution was observed in some tumors. A median reduction of 100% (75 to 100) in the diameter of aneurysmatic/ectatic vascular structures was observed. Our study showed that sirolimus reduces the size of angiomyolipomas by decreasing primarily their highly-vascularized and fat-poor compartments. This effect is associated with a remarkable reduction of tumoral aneurysms/ectatic vessels, revealing the likely mechanism responsible for the risk-decreasing effect of mTOR inhibitors on angiomyolipoma bleeding. These findings support the role of mTOR in the development of angiomyolipoma blood vessels.


Cancers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1334
Author(s):  
Ye Liu ◽  
Zahra Mohri ◽  
Wissal Alsheikh ◽  
Umber Cheema

The development of biomimetic, human tissue models is recognized as being an important step for transitioning in vitro research findings to the native in vivo response. Oftentimes, 2D models lack the necessary complexity to truly recapitulate cellular responses. The introduction of physiological features into 3D models informs us of how each component feature alters specific cellular response. We conducted a systematic review of research papers where the focus was the introduction of key biomimetic features into in vitro models of cancer, including 3D culture and hypoxia. We analysed outcomes from these and compiled our findings into distinct groupings to ascertain which biomimetic parameters correlated with specific responses. We found a number of biomimetic features which primed cancer cells to respond in a manner which matched in vivo response.


2020 ◽  
Vol 134 (8) ◽  
pp. 1001-1025 ◽  
Author(s):  
Sonya Frazier ◽  
Martin W. McBride ◽  
Helen Mulvana ◽  
Delyth Graham

Abstract Placental microRNAs (miRNAs) regulate the placental transcriptome and play a pathological role in preeclampsia (PE), a hypertensive disorder of pregnancy. Three PE rodent model studies explored the role of placental miRNAs, miR-210, miR-126, and miR-148/152 respectively, by examining expression of the miRNAs, their inducers, and potential gene targets. This review evaluates the role of miR-210, miR-126, and miR-148/152 in PE by comparing findings from the three rodent model studies with in vitro studies, other animal models, and preeclamptic patients to provide comprehensive insight into genetic components and pathological processes in the placenta contributing to PE. The majority of studies demonstrate miR-210 is upregulated in PE in part driven by HIF-1α and NF-κBp50, stimulated by hypoxia and/or immune-mediated processes. Elevated miR-210 may contribute to PE via inhibiting anti-inflammatory Th2-cytokines. Studies report an up- and downregulation of miR-126, arguably reflecting differences in expression between cell types and its multifunctional capacity. MiR-126 may play a pro-angiogenic role by mediating the PI3K-Akt pathway. Most studies report miR-148/152 family members are upregulated in PE. Evidence suggests they may inhibit DNA methylation of genes involved in metabolic and inflammatory pathways. Given the genetic heterogeneity of PE, it is unlikely that a single placental miRNA is a suitable therapeutic target for all patients. Investigating miRNAs in PE subtypes in patients and animal models may represent a more appropriate approach going forward. Developing methods for targeting placental miRNAs and specific placental cell types remains crucial for research seeking to target placental miRNAs as a novel treatment for PE.


2021 ◽  
Vol 12 ◽  
Author(s):  
Ellen Menkhorst ◽  
Nandor Gabor Than ◽  
Udo Jeschke ◽  
Gabriela Barrientos ◽  
Laszlo Szereday ◽  
...  

Lectin-glycan interactions, in particular those mediated by the galectin family, regulate many processes required for a successful pregnancy. Over the past decades, increasing evidence gathered from in vitro and in vivo experiments indicate that members of the galectin family specifically bind to both intracellular and membrane bound carbohydrate ligands regulating angiogenesis, immune-cell adaptations required to tolerate the fetal semi-allograft and mammalian embryogenesis. Therefore, galectins play important roles in fetal development and placentation contributing to maternal and fetal health. This review discusses the expression and role of galectins during the course of pregnancy, with an emphasis on maternal immune adaptions and galectin-glycan interactions uncovered in the recent years. In addition, we summarize the galectin fingerprints associated with pathological gestation with particular focus on preeclampsia.


2017 ◽  
Vol 121 (suppl_1) ◽  
Author(s):  
Olan Jackson-Weaver ◽  
Jian Wu ◽  
Yongchao Gou ◽  
Yibu Chen ◽  
Meng Li ◽  
...  

Rationale: Epicardial epithelial-to-mesenchymal trasition (EMT) is a vital process in embryonic heart development. During EMT, epicardial cells acquire migratory and invasive properties, and differentiate into new cell types, including cardiac fibroblasts and coronary smooth muscle cells. Non-histone protein methylation is an emerging modulator of cell signaling. We have recently established a role for protein arginine methyltransferase-1 (PRMT1) in TGF-β-induced EMT in cultured cells. Objective: To determine the role of PRMT1 in epicardial EMT. Methods and Results: We investigated the role of PRMT1 in epicardial EMT in mouse epicardial cells. Embryonic day 9.5 (E9.5) tamoxifen administration of WT1-Cre ERT ;PRMT1 fl/fl ;ROSA-YFP fl/fl mouse embryos was used to delete PRMT1 in the epicardium. Epicardial PRMT1 deletion led to reduced epicardial migration into the myocardium, a thinner compact myocardial layer, and dilated coronary blood vessels at E15.5. Using the epicardial cell line MEC1, we found that PRMT1 siRNA prevented the increase in mesenchymal proteins Slug and Fibronectin and the decrease in epithelial protein E-Cadherin during TGF-β treatment-induced EMT. PRMT1 siRNA also reduced the migration and invasion of MEC1 cells. We further identified that PRMT1 siRNA also increased the expression of p53, a key regulator of the Slug degradation pathway. PRMT1 siRNA increases p53 expression by decreasing p53 degradation, and shifted p53 localization to the cytoplasm. In vitro methylation assays further demonstrated that PRMT1 methylates p53. Knockdown of p53 increased Slug levels and enhanced EMT, establishing p53 as a regulator of epicardial EMT through controlling Slug expression. Furthermore, RNAseq experiments in MEC1 cells demonstrated that 40% (545/1,351) of TGF-β-induced transcriptional changes were prevented by PRMT1 siRNA. Furthermore, when p53 and PRMT1 were simultaneously knocked down, TGF-β induced transcriptional control of 37% (201/545) of these PRMT1-dependent genes was restored. Conclusions: The PRMT1-p53-Slug pathway is necessary for epicardial EMT in cultured MEC1 cells as well as in the epicardium in vivo . Epicardial PRMT1 is required for the development of compact myocardium and coronary blood vessels.


1993 ◽  
Vol 16 (5_suppl) ◽  
pp. 8-12 ◽  
Author(s):  
A.M. Vannucchi ◽  
A. Bosi ◽  
A. Grossi ◽  
S. Guidi ◽  
R. Saccardi ◽  
...  

The issue of the role of erythropoietin (Epo) in the erythroid reconstitution after bone marrow transplantation (BMT) has been addressed in several recent studies. A defective Epo production in response to anemia has been shown to occur in patients undergoing allogeneic BMT unlike in most of those subjected to an autologous rescue. The factors involved in the inadeguate Epo production in BMT are discussed, with particular attention to the role of the immunosuppressive drug cyclosporin-A, which has been shown to inhibit Epo production in both in vivo and in vitro models. The observation of defective Epo production eventually led to the development of clinical trials of recombinant human Epo (rhEpo) administration in BMT patients; the aims of these studies were to stimulate erythroid engraftment, hence reducing blood transfusion exposure. Although the number of patients studied up to now is relatively small, a benefit from rhEpo administration in terms of accelerated erythroid engraftment seems very likely, and it may also be associated with decreased transfusional needs in most treated patients. However, further studies are needed to better define indications, dosages and schedules of rhEpo in BMT patients.


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