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41.
The effect of CardiPro, a polyherbal formulation, with an antioxidant property, has been studied on doxorubicin (DXR)-induced cardiotoxicity in mice. CardiPro (150 mg/kg b.w., twice daily was administered orally for 7 weeks along with four equal injections (each containing 4.0 mg/kg b.w., DXR) intraperitoneally, once weekly (cumulative dose 16 mg/kg). After a 3-week post DXR treatment period, cardiotoxicity was assessed by noting mortality, volume of ascites, liver congestion, changes in heart weight, myocardial lipid peroxidation, antioxidant enzymes and histology of heart. DXR-treated animals showed higher mortality (50%) and more ascites. Myocardial SOD and glutathione peroxidase activity were decreased and lipid peroxidation was increased. Histology of heart of DXR-treated animals showed loss of myofibrils and focal cytoplasmic vacuolization. CardiPro significantly protected the mice from DXR-induced cardiotoxic effects as evidenced by lower mortality (25%), less ascites, myocardial lipid peroxidation, normalization of antioxidant enzymes and minimal damage to the heart histologically. Our data confirm the earlier reports that DXR cardiotoxicity is associated with the free radical-induced tissue damage. Administration of CardiPro, with an antioxidant property, protected the DXR-induced cardiotoxicity in mice.  相似文献   
42.
Activities of whole blood glutathione peroxidase (GSH-Px) and erythrocyte superoxide dismutase (SOD) and serum levels of selenium (Se), copper (Cu) and zinc (Zn) were measured in 118 apparently healthy subjects aged 20-60 years from the city of Ponta Delgada, Island of San Miguel, The Azores Archipelago, Portugal. Data were analysed by age/gender, lipid profile and blood pressure as cardiovascular risk factors searching for their relevance when assessing reference values for antioxidant biomarkers. GSH-Px was in the same range, but SOD was significantly lower than in other Portuguese populations. Neither activity differed with gender. GSH-Px activity increased with age, namely in normolipidemic men versus the hyperlipidemic group in which a decrease was observed. This suggests a progressive impairment of GSH-Px with age caused by an enhanced production of oxidant species in hyperlipidemia. GSH-Px was 30% lower in male hypertensives versus normotensives. SOD activity did not relate to age or blood pressure but was 17% higher in the hyperlipidemic men versus the normolipidemic group, suggesting a better antioxidant protection by SOD than by GSH-Px in hyperlipidemia and hypertension. Se was higher in men versus women, particularly in the older subjects, and partly related to hyperlipidemia. Zn levels showed a similar dependency on gender, not related to age or lipid profile. Cu levels were much higher in women than in men in all age or lipid profile classes and decreased in hyperlipidemia. They were lowered with age in both genders, particularly in normolipidemic women. The present research therefore suggests that hyperlipidemia and hypertension do affect antioxidant status and should be considered when assessing antioxidant biomarkers in blood.  相似文献   
43.
通过盐度渐变和温度骤变的方法,分别研究了不同盐度(10、20、30、40)处理和不同温度(18.0℃、21.0℃、24.6℃、29.0℃、32.0℃)处理对卵形鲳鲹(Trachinotus ovatus)选育群体肝超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GPX)活力的影响.在实验结束时,盐度10组酶活力与对照组无显著差异(P>0.05),盐度20组SOD活力极显著低于对照组(P<0.01);盐度40组120 h时,SOD和GPX活力极显著低于对照组(P<0.01),CAT活力与对照组差异不显著(P>0.05).18.0℃和21.0℃ SOD活力在1、3、6、12、24 h这5个取样时间点均高于对照组,CAT活力在实验结束时(24 h)极显著高于对照组(P <0.01);29.0℃SOD和CAT活力在实验结束时(24 h)显著高于对照组(P<0.05);32.0℃ SOD和CAT活力在5个取样时间点均显著低于对照组(P<0.05).结果表明,适当的盐度或温度变化可以改变卵形鲳鲹肝抗氧化酶活力,达到机体耐受极限时酶活力下降.  相似文献   
44.
Changes in the critical swimming speed (Ucrit, cm s?1) with ontogeny of 2·5–12·5 month‐old juvenile anadromous Chinese sturgeon Acipenser sinesis were measured in a modified Blazka‐type swimming tunnel. The absolute Ucrit increased with length, mass and age; the relative Ucrit (body lengths, s?1), however, decreased. Juvenile A. sinesis did not display a parr–smolt transformation at the length or age threshold to tolerate full‐strength seawater.  相似文献   
45.
Recent studies in fruit flies have imposed dietary restriction (DR) by diluting yeast and have reported increased lifespan as the yeast-to-sugar ratio decreased. In this study, the effects of DR on the lifespan of Bactrocera dorsalis were investigated using constant-feeding diets with different yeast:sugar ratios and an intermittent-feeding diet in which flies ate every sixth day. Antioxidant enzyme activities and the malondialdehyde concentration were also measured in virgin females under constant-feeding DR protocols to investigate their relationships with lifespan. The results showed that B. dorsalis lifespan was significantly extended by DR, and carbohydrate-enriched diet may be important for lifespan-extension. Female flies lived significantly longer than males at all dietary levels under both feeding regimes, indicating no interaction between diet and sex in determining lifespan. Antioxidant enzyme activities increased with the amount of yeast increased in the diets (0–4.76%) between starvation and DR treatments, indicating that the antioxidants may have influences in determining lifespan in B. dorsalis under starvation and DR treatments. However, antioxidants cannot keep up with increased oxidative damage induced by the high yeast diet (25%). These results revealed that the extension of lifespan by DR is evolutionarily conserved in B. dorsalis and that yeast:sugar ratios significantly modulate lifespan in this species.  相似文献   
46.
Water-soluble corn silk polysaccharides (CSPS) were chemically modified to obtain their sulfated, acetylated and carboxymethylated derivatives. Chemical characterization and bioactivities of CSPS and its derivatives were comparatively investigated by chemical methods, gas chromatography, gel filtration chromatography, scanning electron microscope, infrared spectroscopy and circular dichroism spectroscopy, scavenging DPPH free radical assay, scavenging hydroxyl radical assay, ferric reducing power assay, lipid peroxidation inhibition assay and α-amylase activity inhibitory assay, respectively. Among the three derivatives, carboxylmethylated polysaccharide (C-CSPS) demonstrated higher solubility, narrower molecular weight distribution, lower intrinsic viscosity, a hyperbranched conformation, significantly higher antioxidant and α-amylase inhibitory abilities compared with the native polysaccharide and other derivatives. C-CSPS might be used as a novel nutraceutical agent for human consumption.  相似文献   
47.
48.
A phytochemical investigation of the roots of Ferula lutea (Poir.) Maire led to the isolation of new dihydrofuranocoumarins as two inseparable isomers, (?)-5-hydroxyprantschimgin 1 and (?)-5-hydroxydeltoin 2, together with eight known compounds, (?)-prantschimgin 3, (?)-deltoin 4, psoralen 5, xanthotoxin 6, umbelliferone 7, caffeic acid 8, β-sitosterol 9 and stigmasterol 10. Their structures were elucidated on the basis of extensive spectroscopic methods, including 1D and 2D NMR experiments and mass spectroscopy analysis, as well as by comparison with literature data. The anti-acetylcholinesterase and cytotoxic effects of the isolates and antioxidant activities of the mixture (1+2) were also evaluated in this work. Results showed that the mixture (1+2) has the most cytotoxic activity with IC50 values 0.29 ± 0.05 and 1.61 ± 0.57 μM against the cell lines HT-29 and HCT 116, respectively. The greatest acetylcholinesterase inhibitory activity (IC50 = 0.76 ± 0.03) was exhibited by the xanthotoxin 6. In addition, the mixture (1+2) was investigated for its antioxidant activity and showed IC50 values 18.56, 13.06, 7.59, and 4.81 μM towards DPPH free radical scavenging, ABTS radical monocation, singlet oxygen and hydrogen peroxide, respectively.  相似文献   
49.
A novel series of pyrazoline amidoxime (2ad) and pyrazoly-1,2,4-oxadiazole (3ap) and (4) of pharmacological significance have been synthesised. Structures of newly synthesised compounds were characterized by spectral studies. New compounds were screened for their in vitro antioxidant, antimicrobial and antiinflammatory activities. Among the synthesized compounds, compound 2a, 3l and 3o were found to be active antimicrobial agents in addition to having potent antioxidant activity, while the compound 3f showed promising antiinflammatory activity in comparison with standard drug.  相似文献   
50.
Several indole derivatives, that were highly potent ligands of GluN2B-subunit-containing N-methyl-d-aspartate (NMDA) receptor, also demonstrated antioxidant properties in ABTS method. In particular, the 2-(4-benzylpiperidin-1-yl)-1-(5-hydroxy-1H-indol-3-yl)ethanone (1) proved to be a dual-effective neuroprotective agent. With the aim to increase the antioxidant properties we added a catechol moiety onto piperidine moiety. The designed hybrid derivative 3,4-dihydroxy-N-[1-[2-(5-hydroxy-1H-indol-3-yl)-2-oxoethyl]piperidin-4-yl]benzamide (10) was the most effective antioxidant agent (>94.1 ± 0.1% of inhibition at 17 μM) and showed GluN2B/NMDA receptor affinity at low micromolar concentration (IC50 0.66 μM). By means of computational studies we explored the effect of the presence of this antioxidant fragment during the recognition process to binding pocket.  相似文献   
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