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1.
Betulinic acid is one such natural pentacyclic triterpenoid compound, holding various pharmacological properties but its poor bioavailability is the only limitation. One of the biological macromolecules such as Lignin is a plant-derived aromatic, eco-friendly and low-cost polymer that certainly self-assembles into nano-sized colloids. Therefore, onto the current investigation, we increased the bioavailability of betulinic acid by coating on to a nanopolymer prepared with poly vinyl alcohol, lignins and methyl acrylate. Betulinic acid loaded polyvinyl alcohol/ethylacrylate grafted Lignin polymer (PVA/Lig-g-MA) nanoformulation was characterized using FTIR, XRD, SEM and TEM analysis and also the drug entrapment, in vitro drug releasing capacity was done to examine the efficiency of the nanoformulation of a drug. The MTT assay was evaluated the cytotoxicity of synthesized nanoformulation against normal endothelial cells HUVEC and HAPEC to confirm the side effects of the drug. The anti-atherosclerotic property of the nanoformulation was ascertained in both in vitro condition (with HUVEC and HPAEC) and in vivo studies (with Wistar rats). As a result, the characterization studies and in vitro studies clearly confirmed the Betulinic acid loaded PVA/Lig-g-MA nanoformulation is an ideal nanopolymer and it doesn’t cause any cytotoxic effect in normal endothelial cells. It also decreased the lipopolysaccharides induced inflammation through the down-regulation of NFκB and MAP/JNK signaling molecule expressions. Following in vivo results confirmed the synthesized nanoformulation effectively decreased the hyperchlostremia, inflammation and vasoconstriction, which induced over high fat diet. The results of histopathological analysis of cardiac tissues also confirmed the cardioprotective role of synthesized nanoformulation. Overall, both the in vitro and in vivo studies authentically proven the Betulinic acid loaded PVA/Lig-g-MA nanoformulation would be a potent cost effective anti-atherosclerotic nanodrug.  相似文献   
2.
Increased oxidation of low density lipoprotein (LDL) is characteristic of atherosclerosis. In this frame, high density lipoproteins (HDL) play an important role, being able to remove lipid peroxides (LPOs) and cholesterol from oxidized LDL, so exhibiting a protective role against atherosclerosis. A wide range of reactive compounds lead to the oxidation of methionine (Met) residues with the formation of methionine sulphoxide (MetO) in apolipoprotein A‐I (ApoA‐I). Consequently, the determination of MetO level can give both an evaluation of oxidative stress and the reduced capability of ApoA‐I in LPOs and cholesterol transport. For these reasons, the development of analytical methods able to determine the MetO level is surely of interest, and we report here the results obtained by MALDI mass spectrometry. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
3.
Carotid artery stenosis (CAS) is an atherosclerotic disease characterized by a narrowing of the artery lumen and a high risk of ischemic stroke. Risk factors of atherosclerosis, including smoking, hypertension, hyperglycemia, hyperlipidemia, aging, and disrupted circadian rhythm, may potentiate atherosclerosis in the carotid artery and further reduce the arterial lumen. Ischemic stroke due to severe CAS and cerebral ischemic/reperfusion (I/R) injury after the revascularization of CAS also adversely affect clinical outcomes. Melatonin is a pluripotent agent with potent anti-inflammatory, anti-oxidative, and neuroprotective properties. Although there is a shortage of direct clinical evidence demonstrating the benefits of melatonin in CAS patients, previous studies have shown that melatonin may be beneficial for patients with CAS in terms of reducing endothelial damage, stabilizing arterial plaque, mitigating the harm from CAS-related ischemic stroke and cerebral I/R injury, and alleviating the adverse effects of the related risk factors. Additional pre-clinical and clinical are required to confirm this speculation.  相似文献   
4.
Cells respond to alterations in their membrane structure by activating hydrolytic enzymes. Thus, polyunsaturated fatty acids (PUFAs) are liberated. Free PUFAs react with molecular oxygen to give lipid hydroperoxide molecules (LOOHs). In case of severe cell injury, this physiological reaction switches to the generation of lipid peroxide radicals (LOO.). These radicals can attack nearly all biomolecules such as lipids, carbohydrates, proteins, nucleic acids and enzymes, impairing their biological functions. Identical cell responses are triggered by manipulation of food, for example, heating/grilling and particularly homogenization, representing cell injury. Cholesterol as well as diets rich in saturated fat have been postulated to accelerate the risk of atherosclerosis while food rich in unsaturated fatty acids has been claimed to lower this risk. However, the fact is that LOO. radicals generated from PUFAs can oxidize cholesterol to toxic cholesterol oxides, simulating a reduction in cholesterol level. In this review it is shown how active LOO. radicals interact with biomolecules at a speed transcending usual molecule–molecule reactions by several orders of magnitude. Here, it is explained how functional groups are fundamentally transformed by an attack of LOO. with an obliteration of essential biomolecules leading to pathological conditions. A serious reconsideration of the health and diet guidelines is required.  相似文献   
5.
In this work, a detailed mathematical and physical model for calculating the fluidic impedance of an artery is developed. Initially, the model calculates the impedance of a healthy artery, and then, it compares this with the alteration in the impedance of an artery with atherosclerosis. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
6.
The use of click chemistry reactions for the functionalization of nanoparticles is particularly useful to modify the surface in a well‐defined manner and to enhance the targeting properties, thus facilitating clinical translation. Here it is demonstrated that olefin metathesis can be used for the chemoselective functionalization of iron oxide nanoparticles with three different examples. This approach enables, in one step, the synthesis and functionalization of different water‐stable magnetite‐based particles from oleic acid‐coated counterparts. The surface of the nanoparticles was completely characterized showing how the metathesis approach introduces a large number of hydrophilic molecules on their coating layer. As an example of the possible applications of these new nanocomposites, a focus was taken on atherosclerosis plaques. It is also demonstrated how the in vitro properties of one of the probes, particularly its Ca2+‐binding properties, mediate their final in vivo use; that is, the selective accumulation in atherosclerotic plaques. This opens promising new applications to detect possible microcalcifications associated with plaque vulnerability. The accumulation of the new imaging tracers is demonstrated by in vivo magnetic resonance imaging of carotids and aorta in the ApoE?/? mouse model and the results were confirmed by histology.  相似文献   
7.
The interaction between the cell adhesion molecule CD11b and its ligand ICAM-1 plays an important role in inflammatory responses in the disease of atherosclerosis. Atorvastatin is a commonly prescribed statin drug which has been considered as one of the most potent therapeutic agents for atherosclerosis due to its lipid-lowering effect. Recently, there is a growing body of evidence that atorvastatin has anti-inflammatory effect. We have applied the advanced method of live-cell single-molecule force spectros...  相似文献   
8.
IntroductionAtherogenesis,oneofthemajorcausesforthedeathofpeopleinwesterncountries,hastwoprominentproperties.First,itusuallytakesplaceatthebranchesorcurvaturesofthebigarteries,wherethereisanabruptchangeofbloodflow .Secondly ,thereisanaccumulationoflocalf…  相似文献   
9.
具有切应力梯度的平行平板流动腔的构造   总被引:2,自引:0,他引:2  
覃开蓉  柳兆荣  徐刚 《力学季刊》2001,22(3):281-288
在近年来关于流体切应力与细胞力学行为之间关系的研究中,流体切应力梯度被认为是诱发动脉粥样硬化和内膜增生的重要因素之一.本文探讨如何利用常用的离体细胞力学实验工具--平行平板流动腔模拟具有梯度的定常流切应力环境.结果表明,根据Hele-Shaw流的原理和常用复势W(Z)=AZn(n>1)的特性,可构造出具有各种切应力梯度分布的流动腔.与其它模拟切应力梯度的方法比较,本文的方法更加简洁、可行.  相似文献   
10.
IntroductionThemostobviouscharacterofatherosclerosisisthelocalintimalaccumulationoflow_densitylipoprotein(LDL) ,theincreaseofthefiberaltissueandthestenosis.Ononehand ,itisfoundthatthediseaseoftenoccursatthecomplexgeometryregion ,suchasbifurcationzone,cure…  相似文献   
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