Epidermal growth factor receptor inhibition prevents vascular calcifying extracellular vesicle biogenesis

Target analysis and identification of curcumin against vascular calcification

To investigate the mechanism of curcumin (CUR) on vascular calcification (VC), we screen for common targets of CUR and atherosclerosis and verify the targets genes in vivo and in vitro experiments. The common targets of CUR and AS were screened and obtained using different databases. These target genes were analyzed by GO and KEGG pathway enrichment analysis. PPI network analysis was performed and to analyze the key targets. A rat VC model was constructed and CUR was fed for three weeks. The changes of vascular structure and calcium salt deposition were observed in H&E and Von Kossa staining. Further, the expression of these target proteins was detected in the primary VSMCs of VC. The 31 common targets were obtained. GO functional enrichment analysis obtained 1284 terms and KEGG pathway enriched 66 pathways. The key genes were identified in the cytoHubba plugin. The molecular docking analysis showed that CUR bound strongly to EGFR, STAT3 and BCL2. The animal experiments showed the deposition calcium salt reduced by the CUR administration. These proteins BMP2, RUNX2, EGFR, STAT3 and BAX expression were upregulated in VC group and CUR attenuated the upregulated expression. The signal protein Akt and p65 expression increased in VC group and decreased in CUR group. We identified some common target genes of CUR and AS and identified these key genes. The anti-VC effect of CUR was associated with the inhibition of upregulation of EGFR, STAT3 and RUNX2 expression in VSMCs.

Freeze casting to engineer gradient porosity in hydroxyapatite-boron nitride nanotube composite scaffold for improved compressive strength and osteogenic potential

Graded porosity plays a crucial role in scaffolds for bone tissue engineering as it facilitates vital processes such as nutrient diffusion, cellular infiltration, and tissue integration. This paper explores the utilization of freeze casting (FC) as a technique to generate composite scaffolds comprising hydroxyapatite (HA) reinforced with 1D-boron nitride nanotubes (BNNTs) featuring graded porosity and improved compressive strength. Comparative studies were conducted using FC at room and sub-zero temperatures to assess the influence of temperature gradient and heat transfer rate on the production of gradient and aligned porosity in HA-BNNT composites. The FC process with a prolonged thermal gradient facilitated the creation of aligned pores in the HA-BNNT, exhibiting a wide distribution of 60% porosity ranging from 1 to 30 μm. Adding high strength 1 vol% BNNT reinforcement resulted in a remarkable 50% enhancement in compressive strength compared to the control sample. Osteoblasts seeded on the HA-BNNT substrate exhibited significantly higher alkaline phosphate activity, indicating accelerated mineralization compared to the control sample. Gradient porosity and wide pore distribution in the HA-BNNT scaffolds promoted osteogenic activities. Overall, the demonstrated FC processing technique and BNNT addition hold great potential for developing functional and biomimetic scaffolds that can effectively promote tissue regeneration, leading to improved clinical outcomes in bone tissue engineering applications.

Effect of chronic kidney disease induced calcification on peripheral vascular perfusion using near-infrared spectroscopic imaging

Low-cost techniques that can detect the presence of vascular calcification (VC) in chronic kidney disease (CKD) patients could improve clinical outcomes. In this study, we established a near-infrared spectroscopy-based imaging technique to determine changes in peripheral hemodynamics due to CKD-induced VC. Mice were fed a high-adenine diet with either normal or high levels of phosphate to induce CKD with and without VC, respectively. The mice tail was imaged to evaluate hemodynamic changes in response to occlusion. The rate of change in oxyhemoglobin in response to occlusion showed a statistically significant difference in the presence of VC in the mice.

Transcriptional impact of EGFR activation in human female vascular smooth muscle cells

Vascular smooth muscle cells (VSMC) are critical for the vascular tone, but they can also drive the development of vascular diseases when they lose their contractile phenotype and de-differentiate. Previous studies showed that the epidermal growth factor receptor (EGFR) of VSMC is critical for vascular health, but most of the underlying mechanisms by which VSMC-EGFR controls vascular fate have remained unknown. We combined RNA-sequencing and bioinformatics analysis to characterize the effect of EGFR-activation on the transcriptome of human primary VSMC (from different female donors) and to identify potentially affected cellular processes. Our results indicate that the activation of human VSMC-EGFR is sufficient to trigger a phenotypical switch toward a proliferative and inflammatory phenotype. The extent of this effect is nonetheless partly donor-dependent. Our hypothesis-generating study thus provides a first insight into mechanisms that could partly explain variable susceptibilities to vascular diseases in between individuals.