Gefitinib-coated balloon inhibits the excessive hyperplasia of intima after vascular injuries through PI3K/AKT pathway

Receptor Tyrosine Kinase: Still an Interesting Target to Inhibit the Proliferation of Vascular Smooth Muscle Cells

Vascular smooth muscle cells (VSMCs) proliferation is a critical event that contributes to the pathogenesis of vascular remodeling such as hypertension, restenosis, and pulmonary hypertension. Increasing evidences have revealed that VSMCs proliferation is associated with the activation of receptor tyrosine kinases (RTKs) by their ligands, including the insulin-like growth factor receptor (IGFR), fibroblast growth factor receptor (FGFR), epidermal growth factor receptor (EGFR), vascular endothelial growth factor receptor (VEGFR), and platelet-derived growth factor receptor (PDGFR). Moreover, some receptor tyrosinase inhibitors (TKIs) have been found and can prevent VSMCs proliferation to attenuate vascular remodeling. Therefore, this review will describe recent research progress on the role of RTKs and their inhibitors in controlling VSMCs proliferation, which helps to better understand the function of VSMCs proliferation in cardiovascular events and is beneficial for the prevention and treatment of vascular disease.

Intimal Hyperplasia of Arteriovenous Fistula

Intimal hyperplasia (IH), a crucial histopathological injury, forms the basis of vascular stenosis and thrombogenesis. In addition, it is common in maladies such as stenosis at the anastomosis of arteriovenous fistula and restenosis after angioplasty. Various cellular and noncellular components play critical parts in the advancement of IH. This article reviews the distinctive components of IH, such as endothelial dysfunction, multiplication, and movement of vascular smooth muscle cells. Finally, in addition to synthesis of large amounts of extracellular matrix and inflammatory responses, which have frequently been studied in recent years, we offer a premise for clinical treatment with vascular smooth muscle cells.

Preventive Effect and Mechanism of Crossostephium chinense Extract on Balloon Angioplasty-Induced Neointimal Hyperplasia

Balloon angioplasty-induced neointimal hyperplasia remains a clinical problem that must be resolved. The bioactivities of the Crossostephium chinense extract (CCE) have demonstrated potential in preventing the progression of restenosis. The present study evaluated whether CCE can suppress balloon angioplasty-induced neointima formation and elucidated its possible pharmacological mechanisms. A rat model of carotid arterial balloon angioplasty was established to evaluate the inhibitory effect of CCEs on neointimal hyperplasia. Two cell lines, A10 vascular smooth muscle cells (VSMCs) and RAW264.7 macrophages, were used to investigate the potential regulatory activities and pharmacological mechanisms of CCEs in cell proliferation and migration and in inflammation. Our in vitro results indicated that CCE3, the ethanolic extract of C. chinense, exerted the strongest growth inhibitory and antimigratory effects on VSMCs. CCE3 blocked the activation of focal adhesion kinase, platelet-derived growth factor receptor-β (PDGFRB), and its downstream molecules (AKT and mTOR) and reduced the expression of matrix metalloproteinase-2. In addition, our findings revealed that CCE3 significantly increased the expression of miRNA-132, an inhibitory regulator of inflammation and restenosis, and suppressed the expression of inflammation-related molecules (inducible nitric oxide synthase, cyclooxygenase-2, interleukin- (IL-) 1β, and IL-6). Our in vivo study results indicated that balloon injury-induced neointimal hyperplasia was inhibited by CCE3. CCE3 could reduce neointima formation in balloon-injured arteries, and this effect may be partially attributed to the CCE3-induced suppression of PDGFRB-mediated downstream pathways and inflammation-related molecules.

Hydroxysafflor Yellow A inhibits the viability and migration of vascular smooth muscle cells induced by serum from rats with chronic renal failure via inactivation of the PI3K/Akt signaling pathway

It has been reported that the viability and migration of vascular smooth muscle cells contributes to arteriovenous fistula stenosis. Hydroxysafflor Yellow A (HSYA) has been demonstrated to inhibit the viability and migration of VSMCs by regulating Akt signaling. The present study aimed to investigate the role of HSYA on the viability and migration of human umbilical vein smooth muscle cells (HUVSMCs) following stimulation using serum from rats with chronic renal failure (CRF), and to determine the effects of HSYA on PI3K/Akt signaling. Wistar rats were randomly divided into two groups, control and CRF groups. Serum from each group was collected to stimulate the HUVSMCs. Cell Counting Kit-8 and wound healing assays were performed to assess cell viability and migration, respectively. Flow cytometry analysis was performed to assess apoptosis, and western blot analysis was performed to detect protein expression levels of PI3K and Akt. Nitric oxide (NO) production was measured using the Nitrate/Nitrite assay kit. The results demonstrated that serum from CRF rats significantly enhanced cell viability, migration and apoptosis, the effects of which were reversed following treatment with HSYA. In addition, CRF serum decreased NO and endothelial NO synthase expression, whilst increasing the protein expression levels of PI3K and phosphorylated-Akt in HUVSMCs. Notably, treatment with HSYA markedly restored NO production and inactivated the PI3K/Akt signaling pathway. Furthermore, the PI3K/Akt inhibitor, AMG511, exerted similar effects to HSYA. Taken together, the results of the present study suggest that HSYA suppresses cell viability and migration in the presence of CRF serum by inactivating the PI3K/Akt signaling pathway.

The effect of endothelial progenitor cell transplantation on neointimal hyperplasia and reendothelialisation after balloon catheter injury in rat carotid arteries

Background

Reendothelialisation is the natural pathway that inhibits neointimal hyperplasia and in-stent restenosis. Circulating endothelial progenitor cells (EPCs) derived from bone marrow (BM) might contribute to endothelial repair. However, the temporal and spatial distributions of reendothelialisation and neointimal hyperplasia after EPC transplantation in injured arteries are currently unclear.

Methods

A carotid balloon injury (BI) model was established in Sprague-Dawley rats, and PKH26-labelled BM-derived EPCs were transplanted after BI. The carotid arteries were harvested on the first, fourth, seventh, and 14th day post-injury and analysed via light-sheet fluorescence microscopy and pathological staining (n = 3). EPC and human umbilical vein endothelial cell culture supernatants were collected, and blood samples were collected before and after transplantation. The paracrine effects of VEGF, IGF-1, and TGF-β1 in cell culture supernatants and serum were analysed by enzyme-linked immunosorbent assay (n = 4).

Results

Transplanted EPCs labelled with PKH26 were attached to the injured luminal surface the first day after BI. In the sham operation group, the transplanted EPCs did not adhere to the luminal surface. From the fourth day after BI, the mean fluorescence intensity of PKH26 decreased significantly. However, reendothelialisation and inhibition of neointimal hyperplasia were significantly promoted by transplanted EPCs. The degree of reendothelialisation of the EPC^7d and EPC^14d groups was higher than that of the BI^7d and BI^14d groups, and the difference in neointimal hyperplasia was observed between the EPC^14d and BI^14d groups. The number of endothelial cells on the luminal surface of the EPC^14d group was higher than that of the BI^14d group. The number of infiltrated macrophages in the injured artery decreased in the EPC transplanted groups.

Conclusions

Transplanted EPCs had chemotactic enrichment and attached to the injured arterial luminal surface. Although decreasing significantly after the fourth day at the site of injury after transplantation, transplanted EPCs could still promote reendothelialisation and inhibit neointimal hyperplasia. The underlying mechanism is through paracrine cytokines and not differentiation into mature endothelial cells.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02135-w.