Vascular inflammation plays an important role in the pathogenesis and the development of cardiovascular diseases such as arteriosclerosis and restenosis, and the dysfunction of endothelial cells (ECs) may result in the activation of monocytes and other inflammatory cells. ECs exhibit an elongated morphology in the straight part of arteries but a cobblestone shape near the pro-atherogenic region such as branch bifurcation. Although the effects of hemodynamic forces on ECs have been widely studied, it is not clear whether the EC morphology affects its own function and thus the inflammatory response of monocytes. Here we showed that elongated ECs cultured on poly-(dimethyl siloxane) membrane surface with microgrooves significantly suppressed the activation of the monocytes in co-culture, in comparison to ECs with a cobblestone shape. The transfer of EC-conditioned medium to monocytes had the same effect, suggesting that soluble factors were involved in EC-monocyte communication. Further investigation demonstrated that elongated ECs upregulated the expression of anti-inflammatory microRNAs, especially miR-10a. Moreover, miR-10a was found in the extracellular vesicles (EVs) released by ECs and transferred to monocytes, and the inhibition of EV secretion from ECs repressed the upregulation of miR-10a. Consistently, the inhibition of miR-10a expression in ECs reduced their anti-inflammatory effect on monocytes. These results reveal that the EC morphology can regulate inflammatory response through EVs, which provides a basis for the design and the optimization of biomaterials for vascular tissue engineering.
Endothelial cell (EC) morphology can be regulated by the micro/nano topography in engineered vascular grafts and by hemodynamic forces in the native blood vessels. However, how EC morphology affects miRNA and thus EC functions is not well understood. In this study, we addressed this question by using human umbilical vein endothelial cells (HUVECs) cultured on microgrooves as a model. HUVECs were grown on either microgrooved (with 10 μm width/spacing and 3 μm depth) or smooth surfaces. HUVECs on microgrooved surface had elongated and bipolar morphology, while HUVECs on smooth surface showed cobble stone shape or non-polar morphology. EdU staining indicated that HUVECs with elongated morphology had lower proliferation rate compared to their counterpart cultured on smooth surface. Quantitative PCR analysis demonstrated that the expression of the specific microRNAs (miR-10a, miR-19a, miR-221) that targeted proliferation-related genes was all up-regulated. Consistently, the mRNA levels of their respective target genes, mitogen-activated protein kinase kinase kinase 7, Cyclin D1 and c-kit were significantly reduced by a fold change of 0.12 ± 0.01 (p < 0.01), 0.70 ± 0.23 (p < 0.05) and 0.76 ± 0.21 (p < 0.05). Other miRNAs such as miR-126 and miR-181a were up-regulated as well, leading to the repression of their targets vascular cell adhesion molecule-1 and prospero homeobox-1. Our results suggested that microgrooved surface may regulate microRNA levels and thus EC functions. These results provide insight into the modulation of EC functions by microtopographic cues, and will facilitate the rational design of microstructured materials for cell and tissue engineering.
A chemosensor derived from R6G was prepared and introduced to polyamide (PA). The as‐prepared PA showed high sensitivity to some heavy metal ions. Both the color and the fluorescence changed immediately after the addition of heavy metal ions.
Biochemical factors can play an important role in regulating gene expression in human umbilical vein endothelial cells (HUVECs), yet the role of biophysical factors during this process is unknown. Here, we show that physical cues, in the form of parallel microgrooves on the surface of cell adhesive substrates, can change the morphology of HUVECs as well as specific microRNA expression. Cells cultured on microgrooved poly (dimethyl siloxane) (PDMS) surface exhibited a more elongated morphology relative to those cultured on flat surfaces, and favored outgrowth along the axis of groove alignment. The level of microRNAs in the cell was screened by miRNA microchip and verified by qRT-PCR. The result showed that around 26 mi-croRNAs have been modified significantly, among which miR-21 level was dramatically elevated. Western-blotting analysis demonstrated that PTEN, a target of miR-21, was up-regulated in HUVECs with elongated morphology. Cell apoptosis level was significantly decreased, with was associated with the increasing of miR-21 level. These results suggested that biophysical factors can directly modify HUVECs morphology, thus induce miR-21 expression in HUVECs and its downstream biological functions such as decreasing apoptosis. This study provided evidence that surface microtopology should also be considered in designing biomaterials in tissue engineering application.
Aim: Periodontitis is caused by chronic gingival inflammation and affects a large population in the world. Although guided tissue regeneration (GTR) therapy has been proven to be an effective treatment, the deficiency in the symmetrical design of all the GTR membrane in the market leaves large space for improvement. Therefore, we designed a novel asymmetrical bi-layer PLA/gelatin composite membrane for treating periodontitis. Methods: The PLA side was fabricated by electrospinning with metronidazole (MNA) pre-mixed with the PLA solution. The gelatin side containing bioglass (BG) 45S5 was fabricated with freeze-drying process and cross-linked with PLA membrane. The bio-compatibility of the membrane was evaluated in vitro using NIH3T3 cells. The releasing of MNA was measured by spectrophotometer. The bioactivity of the membrane was evaluated by hydroxyapatite (HA) deposit and determined by FTIR spectrometer. The ionic concentration of Ca 2+ and 2 4 SiO − was measured by ICPOES.The expression of the osteogenesis makers was determined by qRT-PCR. Results: The bi-layer PLA/gelatin composite membrane is biocompatible and bioactive. The releasing of MNA can rapidly reach the anti-bacterial effective concentration. Interestingly, the incorporation of MNA modulated the degradation rate of PLA scaffold to meet the requirement of tissue regeneration. Meanwhile, the embedding of the BG powder in the gelatin porous layer provided a favorable Ca 2+ and 2 4SiO − ion environment for the regeneration of the alveolar bone tissue. Conclusions: Taken together, this bi-layer GTR membrane is closer to the physiological structure of the periodontal. The addition of MNA and BG makes it more powerful in treating periodontitis. Moreover, this research provides an example of biomimetic design in fabricating biomaterial for clinical applications.
Vascular inflammation is an important process which contributes to the pathogenesis of many cardiovascular diseases, such as atherosclerosis. MicroRNAs (miRNAs) have been revealed as novel regulators of vascular inflammation. Prior researches had shown that alterations in gene expression of human umbilical vein endothelial cells (HUVECs) associated with topographic cues. Here, we showed that poly (dimethyl siloxane) (PDMS) substrate of 10 μm width and 3 μm depth parallel microgrooves on the surface could significantly upregulate the expression of anti-inflammatory microRNAs, miR-146a and miR-181b. In addition, the results also showed that TRAF6 and importin-α3, target of miR-146a and miR-181b, respectively, were both down-regulated (P < 0.05 and P < 0.001, respectively). The expression levels of the inflammation related proteins were all significantly decreased, including VCAM-1 (P < 0.05), ICAM-1 (P < 0.001), E-selectin (P < 0.001), and MCP-1 (P < 0.05). The adhesion of the mononuclear cell line, THP-1, was significantly decreased (P < 0.05). The results revealed that morphology modified HUVEC can modulate miR-146a and miR-181b and their downstream biological functions such as decreasing inflammation, suggesting that surface microtopology may affect vascular inflammation in the setting of cardiovascular disease. These interesting findings will facilitate the optimal design of microstructured materials in tissue engineering.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.