Influence of combined antioxidants against cadmium induced testicular damage

Acute effects of cadmium (Cd) and combined antioxidants were evaluated in Sprague–Dawley rat testes. The rats were subdivided into four groups. Cadmium chloride (2 mg/kg day) injected intraperitoneally during 8 days. Vitamin C (250 mg/kg day), vitamin E (250 mg/kg day) and sodium selenate (0.25 mg/kg day) were pretreated by gavage in both of control and cadmium injected rats. Testis lipid peroxidation and glutathione levels were determined by spectrophotometrically. In Cd treated rats, lipid peroxidation levels were increased and glutathione levels were decreased and combined antioxidants treatment was effective in preventing of lipid peroxidation and normalizing glutathione. In Cd treated animals, the degenerative changes were observed, but not observed in the administrated rats with Cd and antioxidants under the light microscope. Proliferating cell nuclear antigen, metallothionein and caspase-3 activities were evaluated by immunohistochemically. Proliferation activity was not seen in the spermatogonial cells of cadmium treated testis. Treatment with antioxidants in cadmium administrated testis leads to pronounced increase in proliferation activity. Cytoplasmic caspase-3 activity was determined in the spermatogenic cells but not spermatogonia in treatment of antioxidants with Cd. In control and treated with antioxidants animals, metallothionein expressions were localized in the cells of seminiferous tubules, although the expression only was observed in the interstitial cells of cadmium treated rats. Results demonstrated beneficial effects of combined vitamin C, vitamin E and selenium treatment in Cd toxicity.     

Protective effect of quercetin on experimental chronic cadmium nephrotoxicity in rats is based on its antioxidant properties

Oxidative stress can play a key role in Cd-induced dysfunctions. Quercetin is a potent oxygen free radicals scavenger and a metal chelator. Our aim was to study the effect of quercetin on Cd-induced kidney damage and oxidative stress as well as its mechanism of action. Wistar rats were distributed in four experimental groups: control rats; Cd; quercetin and Cd + quercetin. Renal toxicity was evaluated by measuring urinary excretion of proteins, albumin, glucose and enzymes markers of tubular necrosis, as well as plasma concentration of creatinine. Plasma TBARS concentration and activity of antioxidant enzymes in kidney were also measured. Renal cell damage was assessed by electron microscopy. Animals that received both Cd and quercetin showed a better renal function than those receiving Cd alone. Cd-induced tubular lesions were markedly reduced in rats that also received quercetin. Cd-induced increase in plasma TBARS was prevented by the administration of quercetin. Total plasma antioxidants and renal superoxide dismutase and glutathione-reductase activities were higher in the group that received Cd and quercetin than in rats that received Cd alone. Quercetin administration does not modify the renal content or the urinary excretion of Cd. In conclusion, quercetin treatment prevents renal tubular damage and increased oxidative stress induced by chronic Cd administration, most probably throughout its antioxidant properties.     

Effects of lead exposure on oxidative stress biomarkers and plasma biochemistry in waterbirds in the field

Medina lagoon in Andalusia has one of the highest densities of spent lead (Pb) shot in Europe. Blood samples from waterbirds were collected in 2006–2008 to measure Pb concentration (PbB), δ-aminolevulinic acid dehydratase (ALAD), oxidative stress biomarkers and plasma biochemistry. PbB above background levels (>20 μg/dl) was observed in 19% (n=59) of mallards (Anas platyrhynchos) and in all common pochards (Aythya ferina) (n=4), but common coots (Fulica atra) (n=37) and moorhens (Gallinula chloropus) (n=12) were all <20 μg/dl. ALAD ratio in mallards and coots decreased with PbB levels >6 μg/dl. In mallards, an inhibition of glutathione peroxidase (GPx) and an increased level of oxidized glutathione (oxGSH) in red blood cells (RBC) were associated with PbB levels >20 μg/dl. In coots, PbB levels were negatively related to vitamin A and carotenoid levels in plasma, and total glutathione in RBCs; and positively related with higher superoxide dismutase and GPx activities and % oxGSH in RBCs. Overall, the results indicate that previously assumed background levels of PbB for birds need to be revised.     

Evaluation of Azadirachta indica leaf fractions for in vitro antioxidant potential and in vivo modulation of biomarkers of chemoprevention in the hamster buccal pouch carcinogenesis model

We evaluated the chemopreventive potential of Azadirachta indica (neem) leaf fractions based on in vitro antioxidant assays, and in vivo inhibitory effects on 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis. In addition we also identified the major constituents in neem leaf fractions by HPLC. Analysis of the free radical scavenging activities and reducing potential of crude ethanolic extract (CEE), ethyl acetate fraction (EAF) and methanolic fraction (MF) of neem leaf revealed a concentration-dependent increase in antioxidant potential that was in the order EAF>MF>CEE. Administration of neem leaf fractions reduced the incidence of DMBA-induced HBP carcinomas at a lower concentration compared to the crude extract. Chemoprevention by neem leaf fractions was associated with modulation of phase I and phase II xenobiotic-metabolising enzymes, lipid and protein oxidation, upregulation of antioxidant defences, inhibition of cell proliferation and angiogenesis, and induction of apoptosis. However, EAF was more effective than MF in terms of antiproliferative and antiangiogenic effects, and expression of CYP isoforms. The greater efficacy of EAF may be due to higher content of constituent phytochemicals as revealed by HPLC analysis. The results of the present study suggest that the antioxidant properties of neem leaf fractions may be responsible for modulating key hallmark capabilities of cancer cells such as cell proliferation, angiogenesis and apoptosis in the HBP carcinogenesis model.     

5公里越野训练氧自由基代谢及抗氧化剂的保护作用

目的探讨抗氧化剂对战士5km越野训练氧自由基和尿蛋白的影响。方法选择109名战士为研究对象,分三组。观察服用抗氧化剂维生素C和维生素E后训练,血清超氧化物歧化酶(SOD)活性、丙二醛(MDA)、VitC、VitE、尿蛋白(PRO)、尿微量白蛋白(mALb)水平。探讨这些指标的变化和氧化应激的关系。结果服用抗氧化剂组战士血清SOD、VitC、VE水平升高、MDA、PRO、mALb含量明显降低,与训练组比较有显著性差异(P<0.01)。训练组血清中SOD活性下降,MDA水平升高、PRO、mALb阳性率增高,与对照组比较有显著性差异(P<0.01)。结论补充抗氧化剂可以提高血清中抗氧化酶的活性,降低尿液PRO和mALb的水平,对提高机体抗氧化能力、防止训练后肾损伤,提高部队战斗力具有积极的意义。     

Olive oil enriched in lycopene from tomato by-product through a co-milling process

Abstract

The aim of this investigation was to produce an olive oil (OO) naturally enriched with antioxidants, recovering carotenoids, in particular lycopene, using an industrial by-product of tomato seeds and skin. For this purpose, a technological process in a low-scale industrial plant to co-mill olives and tomato by-product in de-frosted or freeze-dried forms was applied and studied with respect to control samples. Preliminary results obtained from two different experiments were carried out by 40?kg of cultivar Correggiolo olives and 60?kg of olive blends from different cultivars. In both the experiments, the co-milling showed significant enrichment in carotenoids, especially in lycopene (mean values of 5.4 and 7.2?mg/kg oil from defrosted and freeze-dried by-products, respectively). The experimental results demonstrated the possibility to obtain a new functional food naturally enriched in antioxidant compounds, which might be marketed as “OO dressing enriched in lycopene” or “condiment produced using olives and tomato by-product”.     

自由基和抗氧化剂生态网络系统理论模型及应用研究

目的 试图从理论上提出自由基和抗氧化剂生态网络系统理论模型,建立统一的自由基和抗氧化剂生物效应理论模型,解释和定量描述自由基、抗氧化剂生物效应的双相性或多样性,并应用于核化生损伤的医学防护等研究。方法 在总结自由基生物医学最新成果的基础上,提出有关自由基和抗氧化剂的10个基本原理,建立统一的自由基和抗氧化剂生态网络系统理论模型。结果 提出自由基和抗氧化剂生态网络系统理论模型,建立了3个自由基和抗氧化剂生态网络系统理论模型方程,可以解释和定量描述自由基和抗氧化剂生物效应的双相性或多样性,并提出了核化生损伤的统一的氧化还原应激损伤机理和防护措施。结论 提出自由基和抗氧化剂生态网络系统理论模型,解释和定量描述自由基和抗氧化剂生物效应的双相性或多样性。该理论模型适用于其他广义刺激的氧化还原应激:物理因子、化学因子、生物因子、心理、药物、毒物毒素等,可称为广义氧化应激和还原应激的生态网络系统理论模型。     

Protective effects of green tea on intestinal ischemia-reperfusion injury

Objective

The intestinal mucosa is known to be adversely affected by ischemia-reperfusion (I/R). Previously we showed that green tea protects the intestinal mucosa from fasting-induced damage. The aim of this study is to determine whether green tea has any protective role in I/R of the intestine.

Methods

Three groups of male rats were used in this study. Group I (I/R) underwent I/R of the intestine (30 min of ischemia followed by 1 h of reperfusion). Group II (green tea + I/R) was given green tea for 2 wk before inducing I/R. Group III (control) had sham I/R. After the experiments, the jejunum was removed and the tissues were processed for histopathologic examination and immunohistochemical analysis for cell proliferation markers and antioxidant enzymes.

Results

The intestinal mucosa in group II was preserved compared with that in group I. The expressions of cellular proliferation markers (proliferating cell nuclear antigen and Ki-67) and cellular antioxidants (superoxide dismutase and catalase) in group II were similar to those in group III and much less than in group I, reflecting the protective effects of green tea in group II animals.

Conclusion

In this animal model, administration of green tea before inducing I/R protects the intestinal mucosa from injury.     

Prophylaxis against lipopolysaccharide-induced liver injuries by lipoic acid in rats

Lipopolysaccharide (LPS) is a major cell wall molecule of Gram-negative bacteria known to stimulate the synthesis and secretion of several metabolites, such as reactive oxygen species, from phagocytes that play an important role in the pathogenesis of tissue injuries. In this study, the prophylactic effect of the antioxidant lipoic acid was evaluated in an animal acute organ injury model. Animals were pre-treated intraperitoneally with lipoic acid (50 mg kg(-1) body weight) or saline; 3 h later, pretreated animals were challenged intravenously with LPS (Escherichia coli 0111:B4, 1.0 mg kg(-1) body weight) or saline and killed 21 h later. Saline-pretreated animals challenged with LPS were extensively damaged in the liver, as evidenced by an increase in plasma alanine and aspartate aminotransferase activities. Also, LPS injection to saline-pretreated animals resulted in significant increases in plasma tumour necrosis factor-alpha (TNFalpha) and nitric oxide (NO) concentrations, suggestive of activation of the proinflammatory response. The LPS challenge to saline-pretreated animals also increased hepatic myeloperoxidase activity as well as protease and chloramine levels, suggestive of neutrophil infiltration and activation of the inflammatory response. In addition, the involvement of oxidative stress was evident, because a significant increase in lipid peroxidation was observed in the livers of saline-pretreated animals challenged with LPS. The administration of lipoic acid prior to LPS challenge resulted in a significant alleviation of liver injuries, evidenced by a general reversal of the altered biochemical indices toward normal among treated animals. These results indicate that lipoic acid may serve as a potentially effective prophylactic pharmacological agent in alleviating LPS-induced tissue injuries.     

高效液相色谱法同时测定饲料中8种抗氧化剂

目的研究饲料中没食子酸丙酯(PG)、特丁基对苯二酚(TBHQ)、乙氧基喹(EQ)、丁基羟基茴香醚(BHA)、没食子酸辛酯(OG)、二丁基羟基甲苯(BHT)、没食子酸十二酯(DG)和正二氢愈创酸(NDGA)共8种抗氧化剂同时检测系统技术。方法样品提取后采用自动固相萃取方式;定量分析采用高效液相色谱-梯度淋洗-二极管阵列检测器方法进行检测。结果最低检测限为10 mg/kg;饲料中8种抗氧化荆含量在10 mg/kg时实验精密度为1．60％-10．46％;添加抗氧化剂的回收率在84％～106％;。结论该方法具有高效率,高灵敏度,准确度好,可靠性高等技术特点。