Effect of N-acetylcysteine on intimal hyperplasia and endothelial proliferation in rabbit carotid artery anastomosis

Colloidal-fibrillar composite gels demonstrate structural reinforcement, secondary fibrillar alignment, and improved vascular healing outcomes

Many biological tissues contain colloids within a fibrillar structure. Here, we develop and characterize colloidal-fibrillar scaffolds through examination of the effects of relative colloid and fiber ratios within a fibrin-based model system composed of fibrin-based nanoparticles (FBNs) within a natural fibrin scaffold. At lower concentrations, FBNs primarily integrate into the fibrillar fibrin matrix, strengthening it. At high concentrations, colloid-colloid interactions dominate and FBNs primarily form a highly aligned secondary structure that does not strengthen the fibrillar matrix. At intermediate concentrations, both reinforcement of the fibrin matrix and colloid-colloid interactions are observed. Our characterization of this colloidal-fibrillar system provides insight into new avenues for wound healing biomaterial development. Using structural and mechanical results, we developed a biomimetic surgical sealant. When applied to a vascular healing model, FBN gel resulted in improved vessel healing. This colloidal-fibrillar composite can greatly improve healing outcomes and should be applied to other tissues.

The effect of bovine serum albumin-glutaraldehyde and polyethylene glycol polymer on neointimal hyperplasia in rabbit carotid artery anastomosis

OBJECTIVE

Since the systemic drugs have been used to reduce the hyperplasic response in the tunica intima, the periadventitial local drug applications to the vascular wall have gained more popularity. In this study, we investigated the effect of bovine serum albumin-glutaraldehyde and polyethylene glycol polymer on neointimal hyperplasia in rabbit carotid artery anastomosis to explore the effects of these two different agents.

METHODS

21 New Zealand male rabbits were randomly divided into three groups. The carotid artery transection and anastomosis was performed onthe control group. The bovine serum albumin-glutaraldehyde and the polyethylene glycol polymer were applied locally on the other two groups seperatley after transection and anastomosis of the carotid arteries. At the end of 28-day follow-up, the histological and the immunohistochemical results related to neointimal hyperplasia were compared.

RESULTS

The glue residues were detected in the BSA-glutaraldehyde group, but in the PEG polymer group there was no glue residue. The intima thickness and the intima/media thickness ratio in the control group was significantly higher (p<0.05) than the other groups. These values did not differ significantly between the BSA-glutaraldehyde group and the PEG polymer group (p>0.05). The lumen diameter and the area in the control group were significantly higher (p < 0.05) than the BSA-glutaraldehyde group. These values between the control group and the PEG polymer group did not differ significantly (p>0.05). aSMA-positive staining score in the Control group was found to be significantly lower (p < 0.05) than the BSA-glutaraldehyde and PEG polymer group and the VEGF-positive staining score in the control group was found to be significantly higher (p < 0.05) than the BSA-glutaraldehyde and the PEG polymer group.

CONCLUSIONS

Although the both agents have positive results on neointimal hyperplasia, it would be favorable to use polyethylene glycol polymer, since it does not seem to affect the lumen area and the lumen diameter of the vessel.

The diagnostic value of circulating miR-532-5p in patients with asymptomatic carotid artery stenosis and its predictive significance for the occurrence of cerebral ischaemic events

Introduction

Circulating microRNAs (miRNAs) are widely identified as promising and novel biomarkers for the diagnosis of human diseases. This study investigated the clinical value of miR-532-5p for asymptomatic carotid artery stenosis (CAS) patients and detected its predictive value for the occurrence of future cerebral ischaemic events (CIE).

Material and methods

Serum expression of miR-532-5p was measured using qRT-PCR. A receiver operating characteristic (ROC) analysis was performed to evaluate the diagnostic value of miR-532-5p in asymptomatic CAS patients, and the area under the curve (AUC) was calculated. The predictive value of miR-532-5p for the occurrence of CIE was evaluated by using Kaplan-Meier methods and Cox regression analysis.

Results

Serum expression of miR-532-5p was identified to be significantly decreased in CAS patients compared with healthy controls. The ROC curve with an AUC of 0.903 indicated high diagnostic accuracy of serum miR-532-5p expression in asymptomatic CAS patients. As Kaplan-Meier analysis results suggested, more CIE events were observed in cases with low miR-532-5p expression. Low miR-532-5p and high degree of carotid stenosis were independent factors for the occurrence of CIE in asymptomatic CAS patients.

Conclusions

The study suggests the potential clinical value of miR-532-5p for the early diagnosis of asymptomatic CAS patients. MiR-532-5p might have predictive value for the risk of future CIE in asymptomatic CAS patients.