Effect of N‐Acetylcysteine Supplementation on Intracellular Glutathione,Urine Isoprostanes,Clinical Score,and Survival in Hospitalized Ill Dogs

Background

Antioxidant depletion and lipid peroxidation have been correlated with disease severity and associated with poor outcomes.

Hypothesis/Objectives

Supplementing dogs with N‐acetylcysteine (NAC) during the first 48 hours of hospitalization will increase cysteine, normalize glutathione concentrations, and decrease the degree of lipid peroxidation associated with illness.

Animals

Sixty systemically ill hospitalized client‐owned dogs and 14 healthy control dogs.

Methods

Randomized investigator‐blinded, placebo‐controlled prospective study. Dogs were randomized to treatment with NAC (n = 30) versus placebo (n = 30). Antioxidants, urine 8‐isoprostane/creatinine (IP/Cr), and clinical score were determined before and after treatment with NAC. Glutathione, cysteine, and vitamin E concentrations were quantified using high‐performance liquid chromatography. Atomic absorption spectroscopy and enzyme‐linked immunosorbent assays were used to quantify selenium and isoprostane concentrations, respectively.

Results

Ill dogs had significantly lower vitamin E concentrations (27 versus 55 μg/mL; P = .0005) as well as elevated IP/Cr ratios (872 versus 399 pg/mg; P = .0007) versus healthy dogs. NAC supplementation significantly increased plasma cysteine (8.67 versus 15.1 μM; P < .0001) while maintaining glutathione concentrations. Dogs in the placebo group experienced a statistically significant decrease in glutathione concentrations (1.49 versus 1.44 mM; P = .0463). Illness severity and survival were unchanged after short duration NAC supplementation.

Conclusions

Ill dogs experience systemic oxidative stress. Supplementation with NAC during the first 48 hours of hospitalization stabilized erythrocyte glutathione concentrations. The clinical impact of this supplementation and glutathione concentration stabilization was undetermined.     

饮用天然高钼水诱发的钼中毒耕牛主要生物酶测定

本研究对高钼饮水诱导钼中毒的耕牛及对照牛的血浆及组织（肝脏、肺脏、肾脏、脾脏、心脏、肌肉）中超氧化物歧化酶（ＳＯＤ）、黄嘌呤氧化酶（ＸＯＤ）及谷胱甘肽过氧化物酶（ＧＳＨ－ＰＸ）等３种生物酶活性进行了对比分析测定。结果表明,血浆和组织中ＳＯＤ、ＸＯＤ及ＧＳＨ－ＰＸ均随着钼中毒的加重其活性显著下降。这３种生物酶是钼中毒比较灵敏且相关较大的生化指标,对钼中毒具有一定诊断价值;测定ＳＯＤ。ＸＯＤ、ＧＳＨ－ＰＸ可作为钼中毒监测的重要手段。     

两品种小麦叶片衰老过程中清除H2O2能力的差异

引入Ｒｈｔ３矮秆基因的宁矮１号小麦叶片,在全展初期,ＣＡＴ,ＡＰＸ和ＧＲ活力琢ＡｓＡ,ＧＳＨ含量比其亲本苏麦３号高,而在全展后期则不如苏麦３号,这与叶片的光合功能变化相对应。宁矮１号叶片中Ｈ２Ｏ２的累积早于苏麦３号,与其叶片较早地进入衰老相一致。较低浓度的外源Ｈ２Ｏ２对叶片衰老早期的ＣＡＴ,ＡＰＸ和ＧＲ活力有正调节作用、但随着衰老程度的加深,这种调节作用减弱。     

Selenium and vitamin E increases polymorphonuclear cell phagocytosis and antioxidant levels during acute mastitis in riverine buffaloes

Antioxidant, antiinflammatory and phagocytic activities were studied in milk polymorphonuclear cells (PMNs) isolated from healthy buffaloes (group I) and during clinical mastitis with the treatment of Enrofloxacin alone (group II) and combined treatment with Enrofloxacin and Vitamin E plus selenium (group III). On days 0,3, 8 and 15 the milk Somatic cell count (SCC) were significantly higher in mastitic milk than in milk obtained from healthy buffaloes. In group II SCC decreased significantly on day 3 and day 8, however in group III reduction in SCC was observed on day 3, day 8 and day 15 (P < 0.05). The antiinflammatory activity was evaluated by determining nitrite plus nitrate (NOx) production in the milk PMNs before treatment and on day 8. NOx activity was significantly higher in mastitic milk than from healthy controls, both before and after treatment (P < 0.05). In group II and group III the activity decreased significantly on day 8 (P < 0.05). The Glutathione peroxidase (GSH-Px) activity was estimated in the milk polymorphonuclear cell (PMNs) supernatant. GSH-Px activity was significantly lower in mastitic buffaloes than in healthy controls, both before and after treatment (P < 0.05). In group II levels did not change in response to treatment, whereas in group III levels had increased significantly on day 8 (P < 0.05). The phagocytic activity (PA) (percentage of neutrophil that had phagocytosed 1–6 bacteria) and phagocytic index (PI) (average number of bacteria/ leukocytes counted in 100 cells) of the milk PMNs was significantly lower in mastitic buffaloes (P < 0.05). In group II the PA and PI did not change in response to treatment, whereas in group III both the parameters had increased significantly on day 8 (P < 0.05). The results of the present experiment indicated enhancement of antioxidative and cellular defense and reduction of somatic cell count in the mastitic animals treated with Enrofloxacin and Vitamin E plus Selenium as compared to the Enrofloxacin treatment alone. Hence Vitamin E plus selenium therapy may be added along with the antibiotics for effective amelioration of intramammary infection in buffaloes.     

Effects of glutathione treatments during sperm washing and in vitro fertilization on the in vitro early development of embryos of Japanese Black cattle

This study was conducted to examine the effects of adding glutathione (1 mM) to media used for sperm washing and in vitro fertilization (IVF) on the improvement of early development of embryos produced using cryopreserved spermatozoa of the less IVF-competent bull (the one considered unqualified as spermatozoa supplier for the production of bovine blastocysts using IVF). The cryopreserved spermatozoa of this bull were characterized by normal motility and lower ATP content and blastocyst productivity than those of IVF-competent bulls. The addition of glutathione to the sperm washing medium was more effective in improving the productivity of blastocysts and ATP content than the addition of glutathione to the IVF medium or no glutathione addition at all (control). These results suggest that this simple method may be used to improve the potential of cryopreserved spermatozoa of less IVF-competent bulls to fertilize oocytes in vitro and to induce normal embryonic development after fertilization.     

氨氮胁迫对四鼻须鲤鱼肝脏GST酶活力的影响

实验采用生态毒理学方法,以NH4Cl为实验药物,设置0、50、150和250mg/L实验浓度。通过对野生和养殖群体的四鼻须鲤鱼氨氮对肝脏谷胱甘肽巯基转移酶（GST）活力的影响,比较两个群体抗氨氮能力。结果表明：在相同的氨氮浓度和胁迫时间下,四鼻须鲤鱼养殖群体GST酶活力的变化趋势与野生群体大致相同。除250mg/L浓度组在胁迫5d和10d时,野生群体酶活性略低于养殖群体外,在其余时间点的野生群体酶活性均高于养殖群体,而且,在高浓度氨氮胁迫下,野生群体肝脏的GST酶活性达到峰值的时间比养殖群体更短,显示出较强的抗氨氮能力。     

Effects of the commercial extract of aronia on oxidative stress in blood platelets isolated from breast cancer patients after the surgery and various phases of the chemotherapy

Since the extract from berries of Aronia melanocarpa presents antioxidative properties in plasma and in blood platelets, not only from healthy group, but also from patients with benign breast diseases and in patients with invasive breast cancer before surgery, the aim of our present study was to evaluate the oxidative stress by measuring the level of various biomarkers of this process such as the generation of superoxide anion radicals (O(2)(-·)), the amount of carbonyl groups and 3-nitrotyrosine in proteins or the amount of glutathione in blood platelets isolated from breast cancer patients after the surgery and after various phases of the chemotherapy in the presence of A. melanocarpa extract (Aronox) in vitro. We demonstrated in platelet proteins from patients with invasive breast cancer (after the surgery and after various phases of the chemotherapy) higher level of carbonyl groups than in control healthy group. The level of 3-nitrotyrosine in platelet proteins from patients with invasive breast cancer was also significantly higher than in healthy subject group. We observed an increase of other biomarkers of oxidative stress such as O(2)(-·) and a decrease of GSH in platelets from patients with breast cancer (after the surgery and after various phases of the chemotherapy) compared to the healthy group. In model system in vitro our results showed that the commercial extract from berries of A. melanocarpa due to antioxidant action, significantly reduced the oxidative/nitrative stress in platelets from patients with invasive breast cancer caused by the surgery and various phases of the chemotherapy.     

Schisandrin B protects against solar irradiation-induced oxidative injury in BJ human fibroblasts

The effects of schisandrin B (Sch B) and its analogs on solar irradiation-induced oxidative injury were examined in BJ human fibroblasts. Sch B and schisandrin C (Sch C) increased cellular reduced glutathione (GSH) level and protected against solar irradiation-induced oxidative injury. The photoprotection was paralleled by decreases in the elastases-type protease activity and matrix-metalloproteinases-1 expression in solar-irradiated fibroblasts. The cytochrome P-450-mediated metabolism of Sch B or Sch C caused ROS production. The results suggest that by virtue of its pro-oxidant action and the subsequent glutathione antioxidant response, Sch B or Sch C may offer the prospect of preventing skin photo-aging.     

NADP-malic enzyme and glutathione reductase contribute to glutathione regeneration in Fragaria vesca fruit treated with protective high CO2 concentrations

Treatment of harvested strawberries (Fragaria vesca L. Mara des Bois) with high concentrations of CO₂ is an effective means of limiting fungal decay and avoiding disorders caused by low temperature storage. In the present study, we investigated the role of NADP-ME gene expression and activity in lowering malic acid contents and in the provision of NADPH required for the regeneration of the reduced form of glutathione (GSH). We also measured glutathione reductase (GR: EC 1.6.4.2) activity in strawberries treated with different high CO₂ concentrations (0, 20 and 40% for 3 days) during storage at 0 °C. A decrease in malic acid content in fruit exposed to 20% CO₂ was primarily mediated by the stimulation of NADP-ME activity, rather than associated with changes in the expression of cytosolic NADP-ME genes. Moreover, malic acid decarboxylation was associated with a marked increase in GR activity, which may account for the increased levels of glutathione in fruit following exposure to 20% CO₂. This chain of events was not observed in untreated fruit stored in air or in fruit treated with 40% CO₂, suggesting that the unique cellular redox status of 20% CO₂-treated fruit plays an important role in detoxification and protection from damage during storage. Based on these findings, we propose that NADP-ME activation in fruit exposed to 20% CO₂ provides NADPH for glutathione regeneration by GR, thereby conferring protection against the cellular damage caused by low temperatures or excessive high CO₂ levels.     

外源抗坏血酸与谷胱甘肽对打顶后烟草氧化 还原平衡及烟碱的影响

烟碱含量偏高是我国烤烟的现状。如何有效降低烟叶烟碱含量,提高烤烟工业可用性是烟叶生产中的一个难题。根据烟草打顶导致烟碱含量急剧上升和机械损伤造成细胞氧化迸发的的现象,本试验从打顶创伤引起的一系列生理变化入手,采取打顶后在伤口涂抹抗氧化剂抗坏血酸+谷胱甘肽(As A+GSH)和抗坏血酸(As A)两种方法来抑制活性氧含量的上升,探究茉莉酸刺激烟碱含量上升和活性氧含量之间的关系,并比较两种方法在抑制活性氧及烟碱上升的效果。结果发现,涂抹As A+GSH和As A处理对烟草叶片超氧阴离子、过氧化氢、丙二醛的上升有抑制效果,过氧化氢降解速度慢于超氧阴离子,在烟草内有积累现象。涂抹As A+GSH和As A处理在打顶6 h时茉莉酸含量低于常规打顶,对茉莉酸的产生有抑制效果。其中处理96 h后,打顶后涂抹As A+GSH的处理叶片烟碱含量比常规打顶低21.5%,打顶后涂抹As A的处理叶片烟碱含量比常规打顶低17.5%。且各检测指标之间存在显著或极显著的相关性。另外,打顶后24 h,各处理的活性氧含量回到对照(不打顶)的水平。试验表明,抗氧化型物质(As A+GSH)涂抹打顶后烟草的伤口能有效抑制活性氧、茉莉酸和烟碱含量的上升,且活性氧、茉莉酸、烟碱之间存在着密切联系。As A+GSH比As A有更强的抗氧化性,能更好地抑制打顶后烟碱的上升。