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991.
家兔新型动脉粥样硬化狭窄模型的建立及其动态观察 总被引:14,自引:1,他引:13
目的 为血管成形术后再狭窄的研究提供非球囊扩张和动脉造影的简单易行的新型动脉粥样硬化斑块狭窄动物模型。方法 选择日本大耳白兔 18只 (含正常组 6只 ) ,用电刺激血栓形成仪刺激颈总动脉并在术后高脂饲料喂养 6周 ,模型分别于术后 3天、1周、3周、6周处死颈总动脉取材 ,常规病理切片行HE、弹力V G染色 ,光学显微镜观察病理变化。结果 术后 1周内动脉有血栓形成 ,内皮剥脱和部分内弹力板断裂 ,内皮细胞增生 ,中膜局部平滑肌细胞有少量水肿、消失 ,外膜有中性粒细胞浸润 ;术后 3周以上则内膜明显增生 ,内膜下脂质沉积 ,中膜平滑肌细胞核有轻度减少 ,纤维组织及基质增生 ,以损伤部位更明显 ,外膜刺激部位有轻度增厚。术后 6周 6只动物颈总动脉均形成管腔狭窄。结论 用电刺激加高脂饲料喂养的方法可成功建立动脉粥样硬化狭窄的动物模型 ;该模型的病理表现与人类动脉粥样硬化的病理过程相似 ,且避免了二次球囊造模法形成的血管盲端 相似文献
992.
993.
The purpose of this study is to examine the antiarrhythmic and antioxidant effects of tamoxifen, one of the selective estrogen
modulators, in ovariectomized rats subjected to myocardial ischemia-reperfusion (I/R) injury. A month after ovariectomy, rats
were divided into four groups: (I) ovariectomized controls without any treatment, (II) ovariectomized rats treated with vehicle
dimethylsulfoxide (DMSO), (III)–(IV) ovariectomized rats treated with tamoxifen 1 or 10 mg/kg,sc daily for 14 days. To produce
arrhythmia, the left main coronary artery was occluded for 7 min, followed by 7 min of reperfusion. The blood pressure (BP),
heart rate (HR), electrocardiography (ECG) was recorded before and during the ischemia-reperfusion period. The blood levels
of malondialdehyde (MDA), creatine kinase (CK), glutathione (GSH), glutathione peroxidase (GSH-Px), glutathione reductase
(GR), and catalase (CAT) were measured after the rats were killed. Tamoxifen reduced the incidence of ventricular tachycardia
(VT) on ischemia and reperfusion as well as the incidence and duration of reversible ventricular fibrillation (VF) on reperfusion.
I/R injury caused a significant fall in GSH, GSH-Px as well as an increase in MDA and CK levels in the control group when
compared to tamoxifen treated groups. The changes in levels of CAT and GR were however, not significant. In conclusion, our
findings suggest that tamoxifen has cardioprotective effects against I/R injury in rats, likely its antioxidant properties. 相似文献
994.
Oxidative stress and increased oxidation of low-density lipoprotein (oxLDL) through free radical-mediated tissue injury may
be important factors in the development of extracranial atherosclerotic lesions. However, the roles of oxidative stress and
hypercholesterolemia in intracranial atherosclerosis is less established. The induction of heme oxygenase (HO) is a cellular
response to oxidative stress, and inducible HO (HO-1) may protect against oxidized lipids such as those produced by oxidative
stress. We investigated the effects of oxLDL on cell and tissue viability, HO-1 and ferritin expression in extracranial and
intracranial endothelial cells, and the arteries of cholesterol-induced atherosclerosis (CIA) Japanese quail. We report that
cultured microvascular endothelial cells from the brain (QBMEC) and carotid (QCEC) differ in their response to oxidative stress.
The QCECs are less responsive than QBMECs to oxidative stress induced by oxLDL, as evident by lower expression of HO-1 mRNA,
HO activity, and ferritin levels. Furthermore, the higher levels of catalytic iron, thiobarbituric acid reactive substances,
and lactate dehydrogenase released in QCECs indicated that these cells are more susceptible to oxidative stress than QBMECs.
We also investigated the relationship between extent of atherosclerotic plaque deposition and the extracranial and intracranial
arterial expression of HO-1 in quail. The common carotid and vertebral (extracranial) arteries had higher tissue cholesterol
levels (starting at 2 weeks of cholesterol-supplementation) and a greater atherosclerotic plaque score (starting at 4 weeks
of cholesterol-supplementation) compared with middle cerebral and basilar (intracranial) arteries, and this may be relevant
to the effect of aging on the process of atherogenesis. The extracranial arteries also had early and greater levels of lipid
peroxidation and catalytic iron coupled with lower expression of HO-1 protein, HO activity, and ferritin compared to the intracranial
vessels. These observations suggest that the extracranial and intracranial arterial walls respond differently to oxidation
of lipoproteins, and support the feasibility of increased HO-1 expression as a means of protection against oxidant injury. 相似文献
995.
S. Bouderbala M. Lamri-Senhadji J. Prost M.A. Lacaille-Dubois M. Bouchenak 《Phytomedicine》2008,15(6-7):453-461
The aim of the study was to investigate the effect of aqueous extract of Ajuga iva (Ai) on serum and tissues lipid peroxidation as well as antioxidant enzymes activities in red blood cells (RBC) and tissues, in high hypercholesterolemic rats (HC). Male Wistar rats (n=12) were fed on 1% cholesterol-enriched diet for 15 d. After this adaptation phase, hypercholesterolemic rats (total cholesterol=6.5±0.6 mol/l) were divided into two groups fed the same diet and treated or not with Ai for 15 d. Thiobarbituric acid reactive substances (TBARS) concentrations in serum, LDL-HDL1, HDL2 and HDL3 were respectively, 5-, 7.8-, 2.3- and 5-fold lower in Ai treated than untreated hypercholesterolemic groups. TBARS concentrations were 1.4-fold lower in heart and 2.8-fold higher in kidney in Ai-HC treated than untreated HC group. Superoxide dismutase activity was respectively, 1.2- and 1.4-fold higher in RBC and muscle in Ai treated than untreated group. In RBC, Ajuga iva treatment enhanced glutathione peroxidase (GSH-Px) (+9%) and glutathione reductase (GSSH-Red) (+12%) in Ai-HC treated than untreated HC group. GSSH-Red activity was 1.4- and 1.5-fold higher in adipose tissue and heart, respectively and 3.7-fold lower in kidney in Ai treated than untreated group. Liver catalase activity was 1.6-fold higher in Ai treated than untreated group. Adipose tissue and muscle total glutathione content represented in Ai treated group 35% and 36% of the value noted in untreated group. Nitric oxide values of liver, adipose tissue and heart were 3.3-, 2.5- and 3.4-fold higher in Ai-HC than HC group. Ajuga iva treatment enhanced α-tocopherol contents (+25%) in Ai treated than untreated group. In conclusion, Ajuga iva treatment is more effective to improve the antioxidant capacity of RBC than that of tissues. Indeed, Ai is able to reduce the oxidative stress in hypercholesterolemic rats by increasing the antioxidant enzymes activity. 相似文献
996.
4'-Azaflavone (=2-(pyridin-4-yl)-4H-1-benzopyran-4-one; 4) and 3-[(pyridin-4-yl)methyl]-4'-azaflavone (5) were synthesized by a simple environmentally friendly microwave-assisted one-pot method through the cyclization of 3-hydroxy-1-(2-hydroxyphenyl)-3-(pyridin-4-yl)propan-1-one (1), (E)-2'-hydroxy-4-azachalcone (2; chalcone=1,3-diphenylprop-2-en-1-one), and 2'-hydroxy-2-[(hydroxy)(pyridin-4-yl)methyl]-4'-azachalcone (3) under solventless conditions using silica-supported NaHSO(4), followed by treatment with base. In addition, N-alkyl-substituted 4'-azaflavonium bromides 6 and 7 were prepared from compounds 4 and 5, respectively. The antimicrobial and antioxidant activities of compounds 1-7 were tested. The N-alkyl-substituted 4'-azaflavonium bromides 6 and 7 showed high antimicrobial activity against the Gram-positive bacteria and the fungus tested, with MIC values close to those of reference antimicrobials ampicilline and fluconazole. The alkylated compounds 6 and 7 also showed a good antioxidant character in the two antioxidant methods, DPPH (=1,1-diphenyl-2-picrylhydrazyl) radical-scavenging and ferric reducing/antioxidant power (FRAP) tests. 相似文献
997.
Martins FT Doriguetto AC de Souza TC de Souza KR Dos Santos MH Moreira ME Barbosa LC 《化学与生物多样性》2008,5(2):251-258
The composition of the volatile oil obtained by hydrodistillation from the fruit peel of Garcinia brasiliensis (Mart.) Planch. et Triana was determined by GC/MS. A total of 38 components were identified, including gamma-muurolene (10.3%), spathulenol (8.7%), delta-cadinene (8.3%), torreyol (8.0%), alpha-cadinol (7.0%), cadalene (6.3%), and gamma-cadinene (5.3%). Oxygenated sesquiterpenes (43%) were the main group of compounds. The anti-inflammatory activity of the volatile oil was evaluated through the rat-paw edema model induced by carrageenan. Inhibition of the inflammatory process was noticed 3 h after carrageenan administration. In addition, the volatile oil showed poor antioxidant activity. 相似文献
998.
Kim BY Lee KS Choo YM Kim I Je YH Woo SD Lee SM Park HC Sohn HD Jin BR 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2008,150(2):161-169
In insects transferrin is known as an iron transporter, an antibiotic agent, a vitellogenin, and a juvenile hormone regulated protein. Here, a novel functional role for insect transferrin as an antioxidant protein is demonstrated. Stressors, such as heat shock, fungal challenge, and H2O2 exposure, cause upregulation of the white-spotted flower chafer Protaetia brevitarsis (Coleoptera: Scarabaeidae) transferrin (PbTf) mRNA in the fat body and increases PbTf protein levels in the hemolymph. RNA interference (RNAi) treated PbTf reduction causes increased iron and H2O2 levels in the hemolymph and results in induction of apoptotic cell death in the fat body during exposure to stress. The observed effects of PbTf RNAi suggest that PbTf inhibits stress-induced apoptosis by diminishing the Fenton reaction via the binding of iron, thus supporting an antioxidant role for PbTf in stress responses. 相似文献
999.
Primary antioxidant free radical scavenging and redox signaling pathways in higher plant cells 总被引:5,自引:1,他引:4 下载免费PDF全文
Antioxidants in plant cells mainly include glutathione, ascorbate, tocopherol, proline, betaine and others, which are also information-rich redox buffers and important redox signaling components that interact with cellular compartments. As an unfortunate consequence of aerobic life for higher plants, reactive oxygen species (ROS) are formed by partial reduction of molecular oxygen. The above enzymatic and non-enzymatic antioxidants in higher plant cells can protect their cells from oxidative damage by scavenging ROS. In addition to crucial roles in defense system and as enzyme cofactors, antioxidants influence higher plant growth and development by modifying processes from miotosis and cell elongation to senescence and death. Most importantly, they provide essential information on cellular redox state, and regulate gene expression associated with biotic and abiotic stress responses to optimize defense and survival. An overview of the literature is presented in terms of primary antioxidant free radical scavenging and redox signaling in plant cells. Special attention is given to ROS and ROS-anioxidant interaction as a metabolic interface for different types of signals derived from metabolisms and from the changing environment. This interaction regulates the appropriate induction of acclimation processes or execution of cell death programs, which are the two essential directions for higher plant cells. 相似文献
1000.
Małgorzata M. Posmyk Renata Kontek Krystyna M. Janas 《Acta Physiologiae Plantarum》2008,30(4):481-491
Natural phenolic compounds (phenolic acids, flavonoids, tannins, lignans) present in food of plant origin are in the focus
of interest due to their prevalence, properties and biological activity. The aim of the presented work was to investigate
antioxidant and antigenotoxic effects of the anthocyanin-rich extract from red cabbage leaves (Brassica oleracea rubrum) on the changes induced by toxic Cu2+ concentrations. MeOH extract from red cabbage containing anthocyanin (ATH) and phenolic acid derivatives exhibited strong
antioxidant properties. Cu2+ decreased mitotic index (MI) and inhibited proliferative activity of Vicia faba root meristematic cells. The morphology of mitotic chromosomes was changed; “erosion” and pulverization might result from
Cu2+ high-cytotoxicity. Numerous micronuclei, chromatid bridges and lagging/lost chromosomes were found in the meristematic cells
of V. faba, which indicate the clastogenic effect of Cu2+. The application of the ATH-rich extract lowered the number of disturbances induced by Cu2+. The positive role of the ATH-rich red cabbage extract will be discussed. 相似文献