Inhibition of VCAM-1 expression on mouse vascular smooth muscle cells by lobastin via downregulation of p38, ERK 1/2 and NF-κB signaling pathways

Hepatocyte growth factor enhances the ability of dental pulp stem cells to ameliorate atherosclerosis in apolipoprotein E-knockout mice

BACKGROUND

Atherosclerosis (AS), a chronic inflammatory disease of blood vessels, is a major contributor to cardiovascular disease. Dental pulp stem cells (DPSCs) are capable of exerting immunomodulatory and anti-inflammatory effects by secreting cytokines and exosomes and are widely used to treat autoimmune and inflammation-related diseases. Hepatocyte growth factor (HGF) is a pleiotropic cytokine that plays a key role in many inflammatory and autoimmune diseases.

AIM

To modify DPSCs with HGF (DPSC-HGF) and evaluate the therapeutic effect of DPSC-HGF on AS using an apolipoprotein E-knockout (ApoE-/-) mouse model and an in vitro cellular model.

METHODS

ApoE-/- mice were fed with a high-fat diet (HFD) for 12 wk and injected with DPSC-HGF or Ad-Null modified DPSCs (DPSC-Null) through tail vein at weeks 4, 7, and 11, respectively, and the therapeutic efficacy and mechanisms were analyzed by histopathology, flow cytometry, lipid and glucose measurements, real-time reverse transcription polymerase chain reaction (RT-PCR), and enzyme-linked immunosorbent assay at the different time points of the experiment. An in vitro inflammatory cell model was established by using RAW264.7 cells and human aortic endothelial cells (HAOECs), and indirect co-cultured with supernatant of DPSC-Null (DPSC-Null-CM) or DPSC-HGF-CM, and the effect and mechanisms were analyzed by flow cytometry, RT-PCR and western blot. Nuclear factor-κB (NF-κB) activators and inhibitors were also used to validate the related signaling pathways.

RESULTS

DPSC-Null and DPSC-HGF treatments decreased the area of atherosclerotic plaques and reduced the expression of inflammatory factors, and the percentage of macrophages in the aorta, and DPSC-HGF treatment had more pronounced effects. DPSCs treatment had no effect on serum lipoprotein levels. The FACS results showed that DPSCs treatment reduced the percentages of monocytes, neutrophils, and M1 macrophages in the peripheral blood and spleen. DPSC-Null-CM and DPSC-HGF-CM reduced adhesion molecule expression in tumor necrosis factor-α stimulated HAOECs and regulated M1 polarization and inflammatory factor expression in lipopolysaccharide-induced RAW264.7 cells by inhibiting the NF-κB signaling pathway.

CONCLUSION

This study suggested that DPSC-HGF could more effectively ameliorate AS in ApoE-/- mice on a HFD, and could be of greater value in stem cell-based treatments for AS.

"Plug and Play" Functionalized Erythrocyte Nanoplatform for Target Atherosclerosis Management

For atherosclerosis (AS) management, a therapeutic drug intervention is the most widely used strategy. However, there are some problems such as low location specificity, high intake, and side effects. Nanomedicine can prolong the half-life of drug solubilization, reduce toxic and side effects, and improve the distribution of drug objects. Herein, to overcome the challenges, an erythrocyte-based "plug and play" nanoplatform was developed by incorporating the vascular cell adhesion molecule-1 (VCAM-1) targeting and the acid stimulus responsibility. After the function moieties conjugated with DSPE-PEG, the targeting peptide and the acid-sensitive prodrug were conveniently integrated into red blood cells' surface for enhancing target AS drug delivery and controlling local drug release. As a proof of principle, a plug and play nanoplatform with targeted drug delivery and acid-control drug release is demonstrated, achieving a marked therapeutic effect for AS.

SLC39A7 promotes malignant behaviors in glioma via the TNF-α-mediated NF-κB signaling pathway

Purpose: Several studies have indicated that SLC39A7 plays an important role in tumor progression; however, little is known about the function and mechanism of SLC39A7 in glioma. In this study, we aimed to explore the role of SLC39A7 in glioma development. Patients and methods: Bioinformatic analysis was used to predict the role of SLC39A7 in glioma. Cell viability and Edu assays were used to detect the proliferation of glioma cells. A transwell assay was used to measure the invasion and migration of glioma cells. Western blotting, qPCR and ELISA were used to detect the expression of all molecules. Results: SLC39A7 was found to be highly expressed in high-grade glioma patients with a poor prognosis. Our results indicated that SLC39A7 significantly promoted the proliferation, invasion and migration of glioma cells. Furthermore, SLC39A7 promoted tumorigenesis in orthotopic models. We determined that SLC39A7 promotes the malignant behaviors of glioma by activating the TNF-α-mediated NF-κB signaling pathway. Conclusion: Our study revealed that SLC39A7 promotes the proliferation, invasion and migration of glioma cells via the TNF-α-mediated NF-κB signaling pathway, which provides potential targets for glioma therapy.

VCAM-1-targeted and PPARδ-agonist-loaded nanomicelles enhanced suppressing effects on apoptosis and migration of oxidized low-density lipoprotein-induced vascular smooth muscle cells

Purpose: Nanomicelles (NMs) have been widely used for various biomedical applications due to its unique physiochemical properties. The present study aims to investigate the effects of vascular cell adhesion molecule-1 (VCAM-1)-targeted and peroxisome proliferator-activated receptor δ (PPARδ) agonist (GW0742)-loaded NMs on apoptosis and migration in oxidized low-density lipoprotein (ox-LDL)-induced human aortic vascular smooth muscle cells (HAVSMCs).

Methods: The GW0742-loaded NMs (M-GW) and VCAM-1-targeted NMs loaded with GW0742 (TM-GW) were prepared, and then the morphologies and the size distribution of M-GM and TM-GM were observed by transmission electron microscopy (TEM) and dynamic light scattering (DLS), respectively. In vitro drug release assay of M-GM and TM-GM were performed as well. Next, HAVSMCs were cultured in medium containing ox-LDL to mimic atherosclerotic environment, and the effects of free GW0742, M-GM and TM-GM on endocytosis, cell migration and apoptosis, as well as the expression of VCAM-1, and proteins associated with migration and apoptosis were measured in HAVSMCs treated with ox-LDL.

Results: M-GM and TM-GM were successfully prepared. VCAM-1 was overexpressed in HAVSMCs treated with ox-LDL, and TM-GM had a strong targeting ability to HAVSMCs treated with ox-LDL compared with M-GM. In addition, compared with free GW0742, both M-GM and TM-GM significantly diminished cell apoptosis and migration in HAVSMCs treated with ox-LDL.

Conclusions: TM-GM had a superior suppressing effect on apoptosis and migration of ox-LDL-induced HAVSMCs.

Cell adhesion molecule-mediated therapeutic strategies in atherosclerosis: From a biological basis and molecular mechanism to drug delivery nanosystems

Atherosclerosis (AS), characterized by pathological constriction of blood vessels due to chronic low-grade inflammation and lipid deposition, is a leading cause of human morbidity and mortality worldwide. Cell adhesion molecules (CAMs) have the ability to regulate the inflammatory response and endothelial function, as well as potentially driving plaque rupture, which all contribute to the progression of AS. Moreover, recent advances in the development of clinical agents in the cardiovascular field are based on CAMs, which show promising results in the fight against AS. Here, we review the current literature on mechanisms by which CAMs regulate atherosclerotic progression from the earliest induction of inflammation to plaques formation. In particular, we focused on therapeutic strategies based on CAMs inhibitors that prevent leukocyte from migrating to endothelium, including high-affinity antibodies and antagonists, nonspecific traditional medicinal formulas and lipid lowering drugs. The CAMs-based drug delivery nanosystem and the available data on the more reasonable and effective clinical application of CAMs inhibitors have been emphasized, raising hope for further progress in the field of AS therapy.

Adventitial Collagen Crosslink Reduces Intimal Hyperplasia in a Rabbit Arteriovenous Graft Model

BACKGROUND

Intimal hyperplasia (IH) is the initial lesion of vein graft failure after coronary artery bypass grafting. The weak venous wall is likely one of the primary reasons for IH after exposure to the arterial environment. We investigate whether adventitial collagen cross-link by glutaraldehyde (GA) reinforces the venous wall and then reduces IH.

MATERIALS AND METHODS

Adventitial collagen cross-link by 0.3% GA was performed on the rabbit jugular veins. The degree of cross-link was accessed by tensile test. The jugular vein with or without cross-link was implanted into the carotid artery of rabbit. Vein dilatation at the immediate anastomosis and pathological remodeling of vein graft after 4 wk was assessed.

RESULTS

Tensile test indicated that the mechanical property of 3-min cross-linked veins more closely resembled that of the carotid artery. In rabbit arteriovenous graft models, 3-min adventitial collagen cross-link limited overdistension (diameter: 3.24 mm versus 4.65 mm, P < 0.01) at the immediate anastomosis and reduced IH (intima thickness: 78.83 μm versus 140.19 μm, P < 0.01) of vein grafts 4 wk after implantation in the cross-link group as compared with the graft group (without cross-link). Compared with the cross-link group, the expression of proliferating cell nuclear antigen and vascular cell adhesion molecule-1 increased significantly at both the mRNA and protein levels within the graft group (P < 0.01), but the expression of smooth muscle-22α decreased significantly (P < 0.01).

CONCLUSIONS

Adventitial collagen cross-link by GA increased the vessel stiffness and remarkably reduced IH in a rabbit arteriovenous graft model.

YY1 promotes IL-6 expression in LPS-stimulated BV2 microglial cells by interacting with p65 to promote transcriptional activation of IL-6

Neuroinflammation plays a critical role in the process of neurodegenerative disorders, during which microglia, the principal resident immune cells in the central nervous system, are activated and produce proinflammatory mediators. Yin-Yang 1 (YY1), a multi-functional transcription factor, is widely expressed in cells of the immune system and participate in various cellular processes. However, whether YY1 is involved in the process of neuroinflammation is still unknown. In the present study, we found that YY1 was progressively up-regulated in BV2 microglial cells stimulated with lipopolysaccharide (LPS), which was dependent on the transactivation function of nuclear factor kappa B (NF-κB). Furthermore, YY1 knockdown notably inhibited LPS-induced the activation of NF-κB signaling and interleukin-6 (IL-6) expression in BV-2 cells, but not mitogen-activated protein kinase (MAPK) signaling. Moreover, YY1 strengthened p65 binding to IL-6 promoter by interacting with p65 but decreased H3K27ac modification on IL-6 promoter, eventually increasing IL-6 transcription. Taken together, these results for the first time uncover the regulatory mechanism of YY1 on IL-6 expression during neuroinflammation responses and provide new lights into neuroinflammation.

A Novel Urotensin II Receptor Antagonist, KR-36996 Inhibits Smooth Muscle Proliferation through ERK/ROS Pathway

Urotensin II (UII) is a mitogenic and hypertrophic agent that can induce the proliferation of vascular cells. UII inhibition has been considered as beneficial strategy for atherosclerosis and restenosis. However, currently there is no therapeutics clinically available for atherosclerosis or restenosis. In this study, we evaluated the effects of a newly synthesized UII receptor (UT) antagonist, KR-36996, on the proliferation of SMCs in vitro and neointima formation in vivo in comparison with GSK-1440115, a known potent UT antagonist. In primary human aortic SMCs (HASMCs), UII (50 nM) induced proliferation was significantly inhibited by KR-36996 at 1, 10, and 100 nM which showed greater potency (IC₅₀: 3.5 nM) than GSK-1440115 (IC₅₀: 82.3 nM). UII-induced proliferation of HASMC cells was inhibited by U0126, an ERK1/2 inhibitor, but not by SP600125 (inhibitor of JNK) or SB202190 (inhibitor of p38 MAPK). UII increased the phosphorylation level of ERK1/2. Such increase was significantly inhibited by KR-36996. UII-induced proliferation was also inhibited by trolox, a scavenger for reactive oxygen species (ROS). UII-induced ROS generation was also decreased by KR-36996 treatment. In a carotid artery ligation mouse model, intimal thickening was dramatically suppressed by oral treatment with KR-36996 (30 mg/kg) which showed better efficacy than GSK-1440115. These results suggest that KR-36996 is a better candidate than GSK-1440115 in preventing vascular proliferation in the pathogenesis of atherosclerosis and restenosis.

Dibenzofurans and Pseudodepsidones from the Lichen Stereocaulon paschale Collected in Northern Quebec

Chemical investigation of the methanol extract of the lichen Stereocaulon paschale collected in Nunavik, Canada, led to the isolation and identification of two new dibenzofurans (1 and 3) and 11 known lichen metabolites. The structures of the new compounds were established by analysis of 1D and 2D NMR spectroscopic and high-resolution mass spectrometric data. Herein, the first isolation of ascomatic acid dibenzofuran derivatives (1-3) from a whole lichen organism is reported. In addition, some of the isolated metabolites showed antibacterial activity against the oral pathogens Porphyromonas gingivalis and Streptococcus mutans.

Local application of paeonol prevents early restenosis: a study with a rabbit vein graft model

BACKGROUND

Neointimal hyperplasia, which is caused by dysfunction of vascular smooth muscle cells and vascular endothelial cells (VECs), is a foundation for later development of vein grafted occlusion. This study investigates whether neointimal hyperplasia could be prevented by the application of paeonol, a phenolic compound having functions of anti-inflammatory, anti-oxidant, and anti-proliferative.

METHODS

Autologous jugular veins, which engrafted to carotid arteries in rabbits, were enveloped with paeonol or left untreated. After 0, 2, and 3 wk, vein grafts were respectively harvested. Proliferating cell nuclear antigen, vascular cell adhesion molecule l (VCAM-1), and intercellular cell adhesion molecule 1 were assessed with immunohistochemistry and Western blot. VECs apoptosis was also detected with terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling assay.

RESULTS

Paeonol treatment reduced early neointimal hyperplasia by 42%-46% (P < 0.001) and early medial hyperplasia by 18%-22% (P < 0.001) compared with the controls. Immunohistochemical and Western blot results show a significant downregulation of proliferating cell nuclear antigen (P < 0.001) and VCAM-1 (P < 0.001) in paeonol treatment group in the second and third weeks. Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling analysis discovered that VECs apoptosis was also reduced by the paeonol treatment in the second and third weeks (P < 0.001).

CONCLUSIONS

Paeonol could prevent vein graft early restenosis by suppressing intimal and medial hyperplasia via inhibition of vascular smooth muscle cells proliferation, VCAM-1 expression, and anti-apoptosis of VECs in grafted veins.

Ctenopharyngodon idella NF-κB subunit p65 modulates the transcription of IκBα in CIK cells

NF-κB is an important transcription factor for regulating the multiple inflammatory and immune related gene transcription. It can bind with the nuclear factor κB site within the promoter of target genes to regulate their transcriptions. p65, the all-important subunit of NF-κB, is ubiquitously expressed in cells. In the present study, we cloned and identified the p65 subunit from grass carp (Ctenopharyngodon idella) (named Cip65) by homologous cloning and RACE technique. The full length of Cip65 cDNA is 2481 bp along with 9 bp 5' UTR, 639 bp 3' UTR and the largest open reading frame (1833 bp) encoding a polypeptide of 610 amino acids with a well conserved Rel-homology domain (RHD) in N-terminal and a putative transcription activation domain (TAD) in C-terminal. Cip65 gathers with other teleost p65 proteins to form a fish-specific clade clearly distinct from those of mammalian and amphibian counterparts on the phylogenetic tree. In CIK (C. idellus kidney) cells, the expression of Cip65 was significantly up-regulated under the stimulation with Poly I:C. As one member of the NF-κB inhibitor protein (IκB) family, IκBα can dominate the activity of NF-κB by interacting with it. To study the molecular mechanisms of negative feedback loop of NF-κB signaling in fish, we cloned grass carp IκBα (CiIκBα) promoter sequence. CiIκBα promoter is 414 bp in length containing two RelA binding sites and a putative atypical TATA-box. Meanwhile, Cip65 and its mutant proteins including C-terminus deletion mutant of Cip65 (Cip65-ΔC) and N-terminus deletion mutant of Cip65 (Cip65-ΔN) were expressed in Escherichia coli BL21 and purified by affinity chromatography with the Ni-NTA His-Bind resin. In vitro, Cip65 rather than Cip65-ΔC and Cip65-ΔN showed high affinity with CiIκBα promoter sequence by gel mobility shift assays. In vivo, the cotransfection of pcDNA3.1-Cip65 (or pcDNA3.1-Cip65-ΔC, pcDNA3.1-Cip65-ΔN respectively) with pGL3-CiIκBα and pRL-TK renilla luciferase plasmid into CIK cells showed that pcDNA3.1-Cip65 rather than pcDNA3.1-Cip65-ΔC and pcDNA3.1-Cip65-ΔN, can increase the luciferase activity. Taken together, these results suggested that Cip65 can regulate the expression of CiIκBα and works as a negative feedback loop in NF-κB pathway.