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Although low-intensity focused ultrasound (LiFUS) with microbubbles is used to temporally open the blood-brain barrier (BBB), the underlying mechanism is not fully understood. This study aimed to analyze BBB-related alterations in the brain microenvironment after LiFUS, with a focus on the involvement of the purinergic P2 × 7 receptor. Sprague-Dawley rats were sonicated with LiFUS at 0.3 MPa energy. The impact of LiFUS on the P2 × 7 receptor and inflammatory-related proteins, including NLRP3 and interleukin-1β, was analyzed through western blotting. The BBB-associated tight junction proteins, zonula occludens-1 (ZO-1) and occludin, were also analyzed. BBB permeability was assessed by quantifying the amount of Evans blue dye penetration using spectrophotometry. Furthermore, the safety of the sonication procedure was verified via terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and hematoxylin and eosin staining. Substantial increases in the P2 × 7 receptor and its downstream signaling were confirmed after sonicating the BBB with LiFUS for 1 h (p < 0.05). Conversely, for tight junction proteins, the lowest expression was observed at 1 h (p < 0.001). Both responses were normalized back to the original state over time. No evidence of brain damage was observed during the procedure. Furthermore, the P2 × 7 receptor antagonist-injected group showed reduced Evans blue dye penetration compared to that 1 h after FUS, indicating a mitigated impact of LiFUS on the BBB. Herein, we elucidate the underlying mechanism by which LiFUS affects the BBB, with a focus on the involvement of the P2 × 7 receptor. Our findings demonstrate that the extent of BBB opening varies upon the regulation of the P2 × 7 receptor. This study provides valuable insights into the mechanisms underlying BBB modulation through LiFUS, thereby laying the foundation for expanding its applications. [ABSTRACT FROM AUTHOR]

The rapid aging of the population worldwide presents a significant social and economic challenge, particularly due to osteoporotic fractures, primarily resulting from an imbalance between osteoclast-mediated bone resorption and osteoblast-mediated bone formation. While conventional therapies offer benefits, they also present limitations and a range of adverse effects. This study explores the protective impact of Neorhodomela munita ethanol extract (EN) on osteoporosis by modulating critical pathways in osteoclastogenesis and apoptosis. Raw264.7 cells and Saos-2 cells were used for in vitro osteoclast and osteoblast models, respectively. By utilizing various in vitro methods to detect osteoclast differentiation/activation and osteoblast death, it was demonstrated that the EN's potential to inhibit RANKL induced osteoclast formation and activation by targeting the MAPKs-NFATc1/c-Fos pathway and reducing H2O2-induced cell death through the downregulation of apoptotic signals. This study highlights the potential benefits of EN for osteoporosis and suggests that EN is a promising natural alternative to traditional treatments. [ABSTRACT FROM AUTHOR]

Adipose-derived mesenchymal stem cells (ASCs) have the potential to differentiate into bone, cartilage, fat, and neural cells and promote tissue regeneration and healing. It is known that they can have variable responses to hypoxic conditions. In the present study, we aimed to explore diverse changes in the cells and secretome of ASCs under a hypoxic environment over time and to present the possibility of ASCs as therapeutic agents from a different perspective. The expression differences of proteins between normoxic and hypoxic conditions (6, 12, or 24 h) were specifically investigated in human ASCs using 2-DE combined with MALDI-TOF MS analysis, and secreted proteins in ASC-derived conditioned media (ASC-derived CM) were examined by an adipokine array. In addition, genetic and/or proteomic interactions were assessed using a DAVID and miRNet functional annotation bioinformatics analysis. We found that 64 and 5 proteins were differentially expressed in hypoxic ASCs and in hypoxic ASC-derived CM, respectively. Moreover, 7 proteins among the 64 markedly changed spots in hypoxic ASCs were associated with bone-related diseases. We found that two proteins, cathepsin D (CTSD) and cathepsin L (CTSL), identified through an adipokine array independently exhibited significant efficacy in promoting osteocyte differentiation in bone-marrow-derived mesenchymal stem cells (BM-MSCs). This finding introduces a promising avenue for utilizing hypoxia-preconditioned ASC-derived CM as a potential therapeutic approach for bone-related diseases. [ABSTRACT FROM AUTHOR]

Neovessel formation is a complex process governed by the orchestrated action of multiple factors that regulate EC specification and dynamics within a growing vascular tree. These factors have been widely [...]