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61.
Cardioprotective effect of N, α-L-rhamnopyranosyl vincosamide (VR), isolated from the leaves of Moringa oleifera plant in doxorubicin (Dox)-induced cardiac toxicity rats was evaluated. Twelve (12) rats were randomly selected into three groups; two rats received distilled water in the control group, five rats in group I received varying concentration of VR treatment, and group II containing five rats received varying concentration of VR-loaded magnetic hydrogel nanocomposite. Malondialdehyde (MDA), glutathione peroxidase (GSH) and superoxide dismutase (SOD) enzymes activities level were analysed after two weeks. In addition, the expression of three heart failure markers; beta major histocompatibility complex (β-MHC), atrial natriuretic peptide (ANP), and B type natriuretic peptide (BNP) were also evaluated. It was observed that the level of these markers expression decreases with an increase in VR concentration (p?nanogel treated rats possesses a significantly increased VR plasma concentration, Cmax, Kel, t½(a), t½(el), Ka and AUC. The result of this study indicated that VR may help to lower the dosage level, and reduces the treatment course in cardiovascular diseases (CVD). Our conclusion proposes the cardio-protective ability of the isolated VR and its beneficial effect via free radical scavenging properties.  相似文献   
62.
Although auraptene, a prenyloxy coumarin from Citrus species, was known to have anti‐oxidant, anti‐bacterial, antiinflammatory, and anti‐tumor activities, the underlying anti‐tumor mechanism of auraptene in prostate cancers is not fully understood to date. Thus, in the present study, we have investigated the anti‐tumor mechanism of auraptene mainly in PC3 and DU145 prostate cancer cells, because auraptene suppressed the viability of androgen‐independent PC3 and DU145 prostate cancer cells better than androgen‐sensitive LNCaP cells. Also, auraptene notably increased sub‐G1 cell population and terminal deoxynucleotidyl transferase dUTP nick end labeling‐positive cells as features of apoptosis in two prostate cancer cells compared with untreated control. Consistently, auraptene cleaved poly(ADP‐ribose) polymerase, activated caspase‐9 and caspase‐3, suppressed the expression of anti‐apoptotic proteins, including Bcl‐2 and myeloid cell leukemia 1 (Mcl‐1), and also activated pro‐apoptotic protein Bax in both prostate cancer cells. However, Mcl‐1 overexpression reversed the apoptotic effect of auraptene to increase sub‐G1 population and induce caspase‐9/3 in both prostate cancer cells. Taken together, the results support scientific evidences that auraptene induces apoptosis in PC3 and DU145 prostate cancer cells via Mcl‐1‐mediated activation of caspases as a potent chemopreventive agent for prostate cancer prevention and treatment. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
63.
Objectives: Coenzyme Q10 (CoQ10, ubiquinone) stands among the safest supplements in the elderly to protect against cardiovascular disorders. Noteworthy, CoQ10 deficiency is common in many surviving stroke patients as they are mostly prescribed statins for the secondary prevention of stroke incidence lifelong. Accordingly, the current study aims to experimentally examine whether CoQ10 supplementation in animals receiving atorvastatin may affect acute stroke-induced injury.

Methods: Adult rats underwent transient middle cerebral artery occlusion after atorvastatin pretreatment (5 or 10 mg/ kg/day; po; 30 days) with or without CoQ10 (200 mg/kg/day). After 24 hours ischemic/reperfusion injury, animals were subjected to functional assessments followed by cerebral molecular and histological to detect inflammation, apoptosis and oxidative stress.

Results: Animals dosed with 10 mg/kg presented the worst neurological function and brain damage in the acute phase of stroke injury. CoQ10 supplementation efficiently improved functional deficit and cerebral infarction in all stroke animals, particularly those exhibiting statin toxicity. Such benefits were associated with remarkable anti-inflammatory and anti-apoptotic effects, based on the analyzed tumor necrosis factor-α, interleukin-6, Bax/Bcl2 and cleaved caspase 3/9 immunoblots. Importantly, our fluoro-jade staining data indicated CoQ10 may revert the stroke-induced neurodegeneration. No parallel alteration was detected in stroke-induced oxidative stress as determined by malondialdehyde and 8-oxo-2′-deoxyguanosine levels.

Discussion: These data suggest that all stroke animals may benefit from CoQ10 administration through modulating inflammatory and degenerative pathways. This study provides empirical evidence for potential advantages of CoQ10 supplementation in atorvastatin-receiving patients which may not shadow its antioxidant properties.  相似文献   

64.
In this study, the mechanisms involved in vasorelaxant effect of the flavonoid quercetin was investigated in isolated aortic rings from streptozotocin (STZ)-diabetic rats. After 4 weeks, addition of quercetin (0.1 microM-1 mM) caused a significant dose-dependent relaxation of noradrenaline (NA)- and KCl-preconstricted rings in both control and diabetic groups with a significant inter-group difference of P<0.01. Furthermore, both nitro-L-arginine-methyl ester (L-NAME, 100 microM) and indomethacin (10 microM) markedly attenuated the vasorelaxant responses following quercetin application. Meanwhile, endothelium removal significantly attenuated the quercetin-induced vasorelaxation. It is concluded that the quercetin can relax the preconstricted rings of aorta in subchronic STZ-diabetic rats through nitric oxide- and -prostaglandin-mediated pathways, which themselves could be considered as endothelium-dependent.  相似文献   
65.
66.
Natural antioxidants, including polyphenols, flavonoids, anthocyanins and carotenoids, play an important role in the treatment and prevention of a large number of diseases. However, studies indicate that natural antioxidants can act as prooxidants, which produce free radicals and cause DNA damage and mutagenesis. The prooxidant activity is typically catalyzed by metals, particularly transition metals such as Fe and Cu, present in biological systems. In this article, we aim to review new in vitro and in vivo evidence of the prooxidant activity of phenolics, flavonoids, anthocyanins and carotenoids. We highlight the role of catalyzing metals, including transition metals, non‐transition metals and metalloids, in the prooxidant activity of natural antioxidants. Prooxidant structure–activity relationships of simple phenolics, flavonoids and anthocyanins and the role of cellular antioxidant defense, including endogenous antioxidant compounds and antioxidant enzymes, are also addressed in this review. In addition, we discuss the question, With respect to in vitro evidence of the prooxidant activity of antioxidants, can we translate this activity into biological systems and the human body? Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
67.
我们报道成功治疗波氏假阿利什菌引发的真菌性角膜炎1例,患者只留有很小的角膜瘢痕。一位71岁女性患者,有疼痛、红肿和异物感病史,来到我们第三眼科中心就诊。最初角膜刮片显示有真菌成分,2d后真菌培养为阳性,5d后显示生长物为波氏假阿利什菌。患者仅用药物疗法取得临床治愈,留下微小的角膜瘢痕,最终视力为3/10。  相似文献   
68.
我们报道成功治疗波氏假阿利什菌引发的真菌性角膜炎1例,患者只留有很小的角膜瘢痕。一位71岁女性患者,有疼痛、红肿和异物感病史,来到我们第三眼科中心就诊。最初角膜刮片显示有真菌成分,2d后真菌培养为阳性,5d后显示生长物为波氏假阿利什菌。患者仅用药物疗法取得临床治愈,留下微小的角膜瘢痕,最终视力为3/10。  相似文献   
69.
The effect of chronic daidzein, a soybean isoflavone, on aortic reactivity of streptozotocin‐diabetic rats was studied. Male diabetic rats received daidzein for 7 weeks a week after diabetes induction. Contractile responses to KCl and phenylephrine (PE) and relaxation response to acetylcholine (ACh) were obtained from aortic rings. Maximum contractile response of endothelium‐intact rings to PE was significantly lower in daidzein‐treated diabetic rats relative to untreated diabetic rats, and endothelium removal abolished this difference. Endothelium‐dependent relaxation to ACh was significantly higher in daidzein‐treated diabetic rats as compared with diabetic rats and pretreatment of rings with nitric oxide synthase inhibitor N(G)‐nitro‐l‐arginine methyl ester and/or indomethacin attenuated it. Two‐month diabetes also resulted in an elevation of malondialdehyde (MDA) and decreased superoxide dismutase (SOD) activity, and daidzein treatment significantly reversed the increased MDA content and reduced activity of SOD. Therefore, chronic treatment of diabetic rats with daidzein could prevent some abnormal changes in vascular reactivity in diabetic rats through nitric oxide and prostaglandin‐related pathways, and via attenuation of oxidative stress in aortic tissue and endothelium integrity seems essential for this effect. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
70.
A total of 150 bovine (60), ovine (42), and caprine (48) bulk milk samples were analyzed using a commercially available competitive ELISA kit. Overall, AFM1 was found in 46.7 % of the analyzed samples by an average concentration of 40.3 ± 22.2 ng/L. The incidence rates of AFM1 contamination in bovine, ovine, and caprine bulk milk samples were 66.7, 31.0, and 35.4 %, respectively. The concentration of AFM1 in 37.5 % of AFM1-positive bovine milk samples and 5.9 % of AFM1-positive caprine milk samples were higher than 50 ng/L.  相似文献   
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