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81.
82.
The effects of simvastatin, an inhibitor of 3-hydroxy-3-methylglutaryl CoA reductase (HMG-CoA reductase), on oxidative stress resistance and the protective effects of coenzyme Q (CoQ) were investigated. When simvastatin was administered orally to mice, the levels of oxidized and reduced CoQ(9) and CoQ(10) in serum, liver, and heart, decreased significantly when compared to those of control. The levels of thiobarbituric acid reactive substances induced by Fe(2+)-ascorbate in liver and heart mitochondria also increased significantly with simvastatin. Furthermore, cultured cardiac myocytes treated with simvastatin exhibited less resistance to oxidative stress, decreased time to the cessation of spontaneous beating in response to H(2)O(2) addition, and decreased responsiveness to electrical field stimulation. These results suggested that oral administration of simvastatin suppresses the biosynthesis of CoQ, which shares the same biosynthesis pathway as cholesterol up to farnesyl pyrophosphate, thus compromising the physiological function of reduced CoQ, which possesses antioxidant activity. However, these undesirable effects induced by simvastatin were alleviated by coadministering CoQ(10) with simvastatin to mice. Simvastatin also reduced the activity of NADPH-CoQ reductase, a biological enzyme that converts oxidized CoQ to the corresponding reduced CoQ, while CoQ(10) administration improved it. These findings may also support the efficacy of coadministering CoQ(10) with statins.  相似文献   
83.
Previous findings on the association of statins, plasma lipids, and Parkinson's disease (PD) are confounded by the fact that statins also affect lipid profiles. We prospectively examined plasma lipids and statin use in relation to PD in the Atherosclerosis Risk in Communities (ARIC) Study. Statin use and plasma lipids were assessed at baseline (visit 1, 1987‐89) and at three triennial visits thereafter (visits 2‐4) until 1998. Potential PD cases were identified from multiple sources and validated where possible. The primary analysis was limited to incident PD cases diagnosed between 1998 and 2008. Odds ratios and 95% confidence intervals were derived from multivariate logistic regression models. Statin use was rare at baseline (0.57%) but increased to 11.2% at visit 4. During this time frame, total‐cholesterol levels decreased, particularly among statin users. Fifty‐six PD cases were identified after 1998. Statin use before 1998 was associated with significantly higher PD risk after 1998 (odds ratio = 2.39, 95% confidence interval 1.11‐5.13) after adjusting for total cholesterol and other confounders. Conversely, higher total cholesterol was associated with lower risk for PD after adjustment for statin usage and confounders. Compared with the lowest tertile of average total cholesterol, the odds ratios for PD were 0.56 (0.30‐1.04) for the second and 0.43 (0.22‐0.87) for the third tertile (Ptrend = 0.02). Statin use may be associated with a higher PD risk, whereas higher total cholesterol may be associated with lower risk. These data are inconsistent with the hypothesis that statins are protective against PD. © 2015 International Parkinson and Movement Disorder Society  相似文献   
84.
The purpose of this study is to determine the associations between statin use and breast cancer survival and risk by performing a systematic review and meta-analysis. We searched PubMed, Embase and Web of Science up to August 2015 for identifying relevant prospective or case-control studies, or randomized clinical trials. Five prospective studies involving 60,911 patients reported the association between statin use and breast cancer mortality. Eleven prospective studies, 12 case-control studies and 9 randomized clinical trials involving 83,919 patients reported the association between statin use and breast cancer risk. After pooling estimates from all available studies, there was a significantly negative association between pre-diagnosis statin use and breast cancer mortality (for overall survival (OS): hazard ratio (HR) = 0.68, 95% confidence interval (CI) 0.54–0.84; for disease specific survival (DSS): HR = 0.72, 95% CI 0.53–0.99). There was also a significant inverse association between post-diagnosis statin use and breast cancer DSS (HR = 0.65, 95% CI 0.43–0.98), although the association with breast cancer OS did not reach statistical significance (HR = 0.71, 95% CI 0.48–1.07). Additionally, there was a non-linear relationship for the duration of post-diagnosis statin use with breast cancer specific mortality. On the other hand, with regards to the relationship between statin use and breast cancer risk, no significant association was detected. Our analyses suggest that although statin use may not influence breast cancer risk, the use of statin may be associated with decrease mortality of breast cancer patients. Further large-scale studies are warranted to validate our findings.  相似文献   
85.
86.
Coronary heart disease because of atherosclerosis is still the most common cause of mortality. Elevated levels of low‐density lipoprotein and total cholesterol are major risk factors for atherosclerotic cardiovascular disease. The aim of this study was to evaluate the effects of the olive leaf extract on serum lipid profile, early changes of atherosclerosis and endothelium‐dependent relaxations in cholesterol‐fed rats. For this purpose, rats were fed by 2% cholesterol‐enriched or standard chow for 8 weeks. Some rats in each group were also fed orally by olive leaf extract at doses of 50 or 100 mg/kg/day. Atorvastatin at dose of 20 mg/kg of body weight daily was also given as positive control. After 8 weeks, lipid profiles of rat serums were analyzed. Antioxidant enzyme activities (superoxide dismutase and glutathione peroxidase) and degree of lipid peroxidation (malondialdehyde levels) were also measured in the hearts isolated from rats. In addition, expression of adhesion molecules and endothelium‐dependent relaxations of isolated thoracic aortas of rats were evaluated. Total cholesterol and LDL‐cholesterol levels were found to be increased in cholesterol‐fed rats, and both doses of olive leaf extract and atorvastatin significantly decreased those levels. In conclusion, because the olive leaf extract attenuates the increased cholesterol levels, it may have beneficial effects on atherosclerosis. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
87.
Cardiovascular disease is the leading cause of mortality in kidney transplant recipients. Dyslipidemia is a common finding after renal transplantation and a significant risk factor in the development of coronary heart disease. Although a causal relationship with cardiovascular mortality has not been proven in the transplant population, it is reasonable to extrapolate data from the general population and aggressively treat posttransplant dyslipidemia. Statins are considered the agents of choice, though their use may be complicated by drug misadventures. Pravastatin, fluvastatin and pitavastatin are considered to be the safest statins to use in this population; however, given their low‐potency, a high‐potency statin, such as atorvastatin, may be necessary in patients with significant dyslipidemia. In this article, we discuss the etiology of and treatment strategies for dyslipidemia in renal transplant recipients based on a literature review of potential therapeutic adverse effects and benefits in this population. We will also evaluate the reasons for and consequences of the latest Food and Drug Administration (FDA) warnings regarding the use of simvastatin.  相似文献   
88.
Statin monotherapy may not be sufficient to reach serum lipid goals in many patients, especially in those with combined lipid abnormalities. Statins cause only a modest increase in high-density lipoprotein cholesterol (HDL)--an established independent protective factor for coronary heart disease (CHD)--and a modest decrease in triglycerides (TG). Niacin is an effective pharmacologic agent for increasing HDL, as well as lowering TG. Used in combination with a statin, niacin provides an option to help patients attain their low-density lipoprotein cholesterol (LDL-C) goals, non-HDL goals, and HDL goals. Based on the National Health and Nutrition Examination Survey, 1999 to 2000, only 12% of the surveyed adult population were under treatment for diagnosed hypercholesterolemia. Furthermore, only 5.4% of the surveyed population had attained goal total cholesterol levels of < 5.2 mmol/I (< 200 mg/dl). Combination therapy offers a means to get more people to goal. This paper reviews the impact of lipid-modifying combination therapy with niacin plus a statin on lipid profile outcomes.  相似文献   
89.
重组Canstatin蛋白联合氟尿嘧啶治疗胰腺癌   总被引:3,自引:0,他引:3  
目的:探讨血管生成抑制剂Canstatin与细胞毒药物5-FU联合应用治疗胰腺癌的效果,以期探索胰腺癌治疗新途径.方法:胰腺癌SW1990细胞(1×107/只)注射到32只裸鼠皮下,建立胰腺癌皮下移植瘤模型.当肿瘤长至2-3mm时,随机分4组,即PBS(0.3mL/d)对照组、5-FU(12.5mg/(kg·d)×5d)治疗组、Canstatin(10mg/(kg·d)×3wk)治疗组、及5-FU[12.5mg/(kg·d)×5d] Canstatin[10mg/(kg·d)×3wk)]联合治疗组,给药途径均为ip.治疗期间,定期用圆规和游标卡尺测量皮下移植瘤大小.疗程结束时,取下瘤体,常规病理切片,观察药物毒性反应,CD34免疫组化染色,检测肿瘤内微血管密度(MVD).结果:Canstatin治疗组移植瘤体积从第10天起显著小于对照组(P<0.01),5-FU治疗组第7天起就显著小于对照组(P<0.05),而联合治疗组自第3天起,移植瘤体积就显著小于对照组(P<0.05).疗程结束时,联合治疗组小鼠移植瘤体积显著小于其余各组(P<0.01),抑瘤率最高,达83.2%.治疗期间,各实验组未观察到明显毒性反应.免疫组化染色显示,Canstatin组(25.2±3.7)和联合治疗组(22.0±4.8)治疗小鼠肿瘤组织内MVD显著低于对照组(36.8±9.4)和5-FU治疗组(31.6±4.0)(P<0.05),而5-FU治疗组与对照组间无显著差异.结论:重组人Canstatin蛋白能有效抑制人胰腺癌生长,无明显副作用,作用机制是抑制肿瘤新血管形成,与细胞毒药物联合使用,具有协同作用,为胰腺癌治疗提供了新的有力的治疗方法.  相似文献   
90.
Chronic complications of type 2 diabetes, in particular, macrovascular complications, confer substantial morbidity and mortality and adversely affect a patient's quality of life. Early intensive intervention to control cardiovascular risk factors is essential in clinical management. Atherogenic dyslipidaemia characterized by elevated triglycerides, a low level of high-density lipoprotein cholesterol (HDL-C), and an increase in the preponderance of small, dense low-density lipoprotein (LDL) particles, is a key modifiable risk factor for macrovascular diabetic complications. Lowering low-density lipoprotein cholesterol (LDL-C) with a statin (or the combination of statin and ezetimibe) is the main focus for reducing cardiovascular risk in patients with diabetes. However, statins fail to address the residual cardiovascular risk associated with low HDL-C. Fibrates are effective against all components of the atherogenic dyslipidaemia associated with type 2 diabetes. Secondary analyses of the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study suggest a role for early treatment with fenofibrate in improving cardiovascular risk reduction in type 2 diabetes and provide safety data supporting the use of fenofibrate in combination with a statin. Data from the FIELD study suggest that fenofibrate may also have potential to impact on microvascular diabetic complications associated with type 2 diabetes. Data are awaited from the ongoing Action to Control Cardiovascular Risk in Diabetes (ACCORD) study to evaluate the outcome benefits of combining fenofibrate with a statin in patients with type 2 diabetes. Finally, in view of divergent study results and outstanding data, assessment of the risk of the individual with type 2 diabetes is mandatory to assist clinical decision-making when initiating lipid therapy.  相似文献   
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