Time courses of vascular endothelial growth factor and intercellular adhesion molecule-1 expressions in aortas of atherosclerotic rats

Cordycepin inhibits vascular adhesion molecule expression in TNF-α-stimulated vascular muscle cells

Atherosclerosis is a chronic inflammatory disease, which is associated with the increased expression of adhesion molecules in vascular smooth muscle cells (VSMCs). Cordycepin is one of the major bioactive components of Ophiocordyceps sinensis that has been demonstrated to exert anti-atherogenic activity; however, its molecular mechanisms are poorly understood. The aim of the present study was to examine the in vitro effects of cordycepin on the tumor necrosis factor (TNF)-α-induced suppression of adhesion molecule expression. The results of the present study demonstrated that cordycepin markedly inhibited the expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) in TNF-α-stimulated human aortic vascular smooth muscle cells (HA-VSMCs). Cordycepin significantly inhibited the TNF-α-induced mitogen-activated protein kinase (MAPK) and protein kinase B (Akt) activation (P<0.05), markedly inhibited the TNF-α-induced expression level of nuclear factor (NF)-κB p65 and markedly prevented the TNF-α-associated degradation of IκBα in HA-VSMCs. The results of the present study suggest that cordycepin inhibits the expression of VCAM-1 and ICAM-1 in TNF-α-stimulated HA-VSMCs via downregulating the MAPK/Akt/NF-κB signaling pathway. Therefore, cordycepin may have a potential therapeutic application for preventing the advancement of atherosclerotic lesions.

Matrine inhibits the expression of adhesion molecules in activated vascular smooth muscle cells

Atherosclerosis is a chronic inflammatory disease associated with increased expression of adhesion molecules in vascular smooth muscle cells (VSMCs). Matrine is a main active ingredient of Sophora flavescens roots, which are used to treat inflammatory diseases. However, the effects of matrine on the expression of adhesion molecules in VSMCs have largely remained elusive. Therefore, the present study investigated the effects of matrine on the expression of adhesion molecules in tumor necrosis factor (TNF)‑α‑stimulated human aortic smooth muscle cells (HASMCs). The results showed that matrine inhibited the expression of vascular cell adhesion molecule‑1 (VCAM‑1) and intercellular adhesion molecule‑1 (ICAM‑1) in TNF‑α‑stimulated HASMCs. Matrine markedly inhibited the TNF‑α‑induced expression of nuclear factor (NF)‑κB p65 and prevented the TNF‑α‑caused degradation of inhibitor of NF‑κB; it also inhibited TNF‑α‑induced activation of mitogen‑activated protein kinases (MAPKs). Furthermore, matrine inhibited the production of intracellular reactive oxygen species (ROS) in TNF‑α‑stimulated HASMCs. In conclusion, the results of the present study demonstrated that matrine inhibited the expression of VCAM‑1 and ICAM‑1 in TNF‑α‑stimulated HASMCs via the suppression of ROS production as well as NF‑κB and MAPK pathway activation. Therefore, matrine may have a potential therapeutic use for preventing the advancement of atherosclerotic lesions.

Behavioural, metabolic, and endothelial effects of the TNF-α suppressor thalidomide on rats subjected to chronic mild stress and fed an atherogenic diet

There is accumulating evidence suggesting that depression is a risk factor for cardiovascular diseases. This study aimed to examine the hypothesis that the proinflammatory cytokine TNF-α would partially explain the link between depression and atherosclerotic endothelial changes. Rats were distributed among 6 groups: (i) control group; (ii) group subjected to chronic mild stress (CMS); (iii) group fed a cholesterol–cholic acid–thiouracil (CCT diet); and (iv) CMS group fed the CCT diet and treated with the vehicle for 8 weeks. The last 2 groups were subjected to CMS–CCT and received thalidomide (THAL) or imipramine (IMIP). Rats were assessed behaviorally (sucrose preference, open field, and forced-swimming tests). TNF-α protein was assessed from the serum, aorta, and liver. Aortic TNF-α gene expression (assessed using RT–PCR), serum lipid profile, and insulin levels were measured. Endothelial function was assessed in isolated aortic rings. The THAL and IMIP groups showed ameliorated CMS–CCT-related behavioral changes. CMS–CCT-induced metabolic and endothelial dysfunctions were improved in the THAL group but were worsened in the IMIP group. RT–PCR showed a significant reduction of aortic TNF-α mRNA expression in the THAL and IMIP treatment groups. These data paralleled the findings for aortic immunohistochemistry. The THAL group, but not the IMIP group, showed improved CMS–CCT-induced changes in the vascular reactivity of the aortic rings. Thus, TNF-α provides a target link between depression, metabolic syndrome, and endothelial dysfunction. This could open a new therapeutic approach to address the comorbidities of depression.

Effect of the Kv1.3 voltage-gated potassium channel blocker PAP-1 on the initiation and progress of atherosclerosis in a rat model

Acute coronary syndrome is a serious medical emergency. It occurs when an atherosclerotic plaque ruptures, leading to thrombus formation within a coronary artery. Previous studies have shown that T cells are involved in the initiation and progression of acute coronary syndrome. CD4(+)CD28(null) T lymphocytes increase in atherosclerotic plaque, and voltage-gated potassium channel Kv1.3 blockers can suppress the function of these cells in vitro by preventing exocytosis of their cytoplasmic granules. The purpose of this study was to investigate the effect of PAP-1, a small molecule voltage-gated potassium channel Kv1.3 blocker, on the development of atherosclerosis (AS) in a rat model and the potential mechanism for this effect. Plasma lipids, interferonγ, CRP, CD4(+)CD28(null) T cells, and perforin were increased and unstable atherosclerotic plaques developed in the rat model of AS. Blockade of the Kv1.3 potassium channel via PAP-1 administration decreased perforin levels and prevented plaque formation but had no effect on the other changes seen in this AS model. These findings suggest that the small molecule, voltage-gated potassium channel Kv1.3 blocker PAP-1 can suppress the development of AS in a rat model, most likely by inhibiting the exocytosis of cytoplasmic granules from CD4(+)CD28(null) T cells.

The effects of two Lactobacillus plantarum strains on rat lipid metabolism receiving a high fat diet

The aim of our study was to evaluate the effects of the different probiotic strains, Lactobacillus plantarum LS/07 and Lactobacillus plantarum Biocenol LP96, on lipid metabolism and body weight in rats fed a high fat diet. Compared with the high fat diet group, the results showed that Lactobacillus plantarum LS/07 reduced serum cholesterol and LDL cholesterol, but Lactobacillus plantarum Biocenol LP96 decreased triglycerides and VLDL, while there was no change in the serum HDL level and liver lipids. Both probiotic strains lowered total bile acids in serum. Our strains have no significant change in body weight, gain weight, and body fat. These findings indicate that the effect of lactobacilli on lipid metabolism may differ among strains and that the Lactobacillus plantarum LS/07 and Lactobacillus plantarum Biocenol LP96 can be used to improve lipid profile and can contribute to a healthier bowel microbial balance.

Local arterial nanoparticle delivery of siRNA for NOX2 knockdown to prevent restenosis in an atherosclerotic rat model

Both atherosclerosis and arterial interventions induce oxidative stress mediated in part by nicotinamide adenine dinucleotide phosphate (NADPH) oxidases that have a pivotal role in the development of neointimal hyperplasia and restenosis. For small interfering RNA (siRNA) targeting of the NOX2 (Cybb) component of the NADPH oxidase to prevent restenosis, gene transfer with viral vectors is effective, but raises safety issues in humans. We developed a new approach using the amino-acid-based nanoparticle HB-OLD7 for local delivery of siRNA targeting NOX2 to the arterial wall. siRNA-nanoparticle complexes were transferred into the regional carotid artery walls after angioplasty in an atherosclerotic rat model. Compared with angioplasty controls, Cybb gene expression (measured by quantitative reverse transcriptase-PCR) in the experimental arterial wall 2 weeks after siRNA was reduced by >87%. The neointima-to-media-area ratio was decreased by >83%, and the lumen-to-whole-artery area ratio was increased by >89%. Vital organs showed no abnormalities and splenic Cybb gene expression showed no detectable change. Thus, local arterial wall gene transfer with HB-OLD7 nanoparticles provides an effective, nonviral system for efficient and safe local gene transfer in a clinically applicable approach to knock down an NADPH oxidase gene. Local arterial knockdown of the Cybb gene significantly inhibited neointimal hyperplasia and preserved the vessel lumen without systemic toxicity.

Anti-atherogenic effects of centipede acidic protein in rats fed an atherogenic diet

AIM OF THE STUDY

To investigate the effects of centipede acidic protein (CAP) on atherosclerotic rats and the mechanisms involved.

MATERIALS AND METHODS

Male Sprague-Dawley rats were randomly divided into five groups: control, atherosclerotic, low-dose CAP (L-CAP), high-dose CAP (H-CAP) and simvastatin group (n=12 in each group). Atherosclerotic model was established by a single dose of vitamin D(3) and an atherogenic diet. Rats of H-CAP and simvastatin groups simultaneously received CAP or simvastatin daily for 6 weeks. At the completion of the experiment, the changes in lipid profile, hemorrheology, nitric oxide (NO), endothelin-1 (ET-1), malondialdehyde (MDA) and superoxide desmutase (SOD) were measured, and the histological changes in aorta and liver were observed.

RESULTS

Treatment of atherosclerotic rats with either low or high doses of CAP led not only to significant decreases in plasma total cholesterol, triglyceride, low density lipoprotein and increase in plasma high density lipoprotein, but also to improvement of the hemorrheologic abnormalities. On the other hand, CAP suppressed the lipid peroxidation, regulated the levels of ET-1 and NO. From the histopathological examination, treatment with CAP ameliorated the pathological changes in thoracic aorta and liver in atherosclerotic rats.

CONCLUSIONS

These results suggest that CAP significantly suppress the development of atherosclerosis, improves the hemorrheological disturbances and histopathological changes in the atherogenic diet fed rat model. These effects may partly attribute to reverse of dyslipidemia, inhibition of lipid peroxidation, regulation of NO and ET-1 system.

Proteomic analysis of rat aorta during atherosclerosis induced by high cholesterol diet and injection of vitamin D3

1. Atherosclerosis (AS) in rats displays important clinical similarities to human AS. 2. After the experimental model of AS in rat was established and using a proteomic approach, we compared the protein profiling of aorta tissues from healthy and AS rats. 3. Using two-dimensional electrophoresis (2-DE), over 1878 protein species were separated; among them, 1239 protein spots were matched between different gels with average matching rate of approximately 66%. Gel analysis and protein characterization have identified 58 protein spots whose abundance is significantly altered in AS rats. 4. By using matrix-associated laser desorption ionization time-of-flight mass spectrometer (MALDI-TOF-MS) and NCBInr database, 46 proteins were successfully identified. Among them, 18 proteins were of increased abundance in diseased tissues including a group of oxidization-related enzymes such as peroxiredoxin2 and NADH dehydrogenase Fe-S protein 6, components of inflammatory pathways such as lamin A, while 28 proteins were of decreased abundance in the diseased state, including CaM-KII inhibitory protein, transferring, fructose-bisphosphate aldolase. 5. We believe that these results would give insights into the cellular and molecular mechanisms involved in AS development and might lead to the discovery of novel diagnostic markers and new therapeutic opportunities.