There have been several reported studies on the distribution and/or toxicity of nanosilica particles. However, the influence of these particles on blood vessels through which they are distributed is poorly understood. Hence, we investigated the effects of nano- and micromaterials on blood vessel shrinkage and relaxation. Nanosilica particles with diameters of 70 nm (nSP70) were used as the nanomaterial, and particles of 300 and 1000 nm (nSP300 and mSP1000, respectively) were used as micromaterials. A rat thoracic aorta was used as the test blood vessel. The nano- and micromaterials had no effect on vessel shrinkage. Of the nano- and micromaterials tested, only nSP70 strongly evoked vascular relaxation. Vascular relaxation evoked by nSP70 was almost completely inhibited by the phosphoinositide 3-kinase (PI3K) inhibitor wortmannin. In addition, the selective nitric oxide synthesis inhibitor NG-nitro-l-arginine methyl ester, which inhibits endothelial nitric oxide synthase (eNOS) downstream of PI3K signaling, inhibited vascular relaxation evoked by nSP70. In an analysis using bovine aortic endothelial cells (bAECs), nSP70 phosphorylated protein kinase B (AKT) and eNOS acted downstream of PI3K signaling. PI3K inhibition by wortmannin reduced AKT and eNOS phosphorylation. These results demonstrated that 70-nm amorphous nanosilica particles evoked vascular relaxation through PI3K/Akt/eNOS signaling. Moreover, it was suggested that nanomaterials, in general, control or disrupt vascular function by activating a known signal cascade.

Download full-text PDF

Source
http://dx.doi.org/10.1111/fcp.12206DOI Listing

Publication Analysis

Top Keywords

vascular relaxation
20
nanosilica particles
16
nano- micromaterials
12
amorphous nanosilica
8
relaxation pi3k/akt/enos
8
pi3k/akt/enos signaling
8
blood vessel
8
vessel shrinkage
8
evoked vascular
8
relaxation evoked
8

Similar Publications

Establishing a standardized murine orthotopic intra-rectal model for the study of colorectal adenocarcinoma.

J Gastrointest Oncol

December 2024

Medical Physics Unit, Department of Oncology, Faculty of Medicine, McGill University, Montreal, QC, Canada.

Background: Orthotopic models offer a more accurate representation of colorectal cancer (CRC) compared to subcutaneous models. Despite promising results from the reported intra-rectal models, establishing a standardized method for CRC research remains challenging due to model variability, hindering comprehensive studies on CRC pathogenesis and treatment modalities, such as brachytherapy. This study aimed to establish a standardized workflow for an orthotopic intra-rectal animal model to induce the growth of colorectal adenocarcinoma in male and female mice.

View Article and Find Full Text PDF

Stay connected: The myoendothelial junction proteins in vascular function and dysfunction.

Vascul Pharmacol

January 2025

Department of Clinical and Biological Sciences, University of Torino, Regione Gonzole 10, 10043 Orbassano, Italy. Electronic address:

The appropriate regulation of peripheral vascular tone is crucial for maintaining tissue perfusion. Myoendothelial junctions (MEJs), specialized connections between endothelial cells and vascular smooth muscle cells, are primarily located in peripheral resistance vessels. Therefore, these junctions, with their key membrane proteins, play a pivotal role in the physiological control of relaxation-contraction coupling in resistance arterioles, mainly mediated through endothelium-derived hyperpolarization (EDH).

View Article and Find Full Text PDF

Primary-lobe-based trilobed and quadrilobed flaps for reconstruction of nasal tip skin defects.

JPRAS Open

March 2025

Department of Plastic and Craniofacial Surgery, MITERA Hospital, Hellenic Healthcare Group (HHG), 6 Erithrou Stavrou str., 151 23 Maroussi, Attica, Greece.

Background: Despite a variety of principles proposed for drawing trilobed and quadrilobed flaps for the reconstruction of nasal skin defects, the application of these principles in a detailed and reliable way remains questionable.

Methods: We present a novel method for drawing trilobed and quadrilobed flaps to cover nasal tip skin defects. The method is based on the use of templates corresponding to four trilobed flaps with overall angles of 60°, 70°, 80°, and 90°, and two quadrilobed flaps with angles of 90° and 105°.

View Article and Find Full Text PDF

Heart failure is a prevalent global health issue. Heart failure with preserved ejection fraction (HFpEF), which already represents half of all heart cases worldwide, is projected to further increase, driven by aging populations and rising cardiovascular risk factors. Effective therapies for HFpEF remain limited, particularly due to its pathophysiological heterogeneity and incomplete understanding of underlying pathomechanisms and implications.

View Article and Find Full Text PDF

Klebsiella pneumoniae-derived extracellular vesicles impair endothelial function by inhibiting SIRT1.

Cell Commun Signal

January 2025

Beijing An Zhen Hospital, Capital Medical University, The Key Laboratory of Remodeling Cardiovascular Diseases, Ministry of Education; Collaborative Innovation Center for Cardiovascular Disorders, Beijing Institute of Heart Lung and Blood Vessel Disease, Beijing, 100029, China.

Background: The potential role of Klebsiella pneumoniae (K.pn) in hypertension development has been emphasized, although the specific mechanisms have not been well understood. Bacterial extracellular vesicles (BEVs) released by Gram-negative bacteria modulate host cell functions by delivering bacterial components to host cells.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!