Combined effects of temperature and copper ion concentration on the superoxide dismutase activity in Crassostrea ariakensis

Superoxide dismutase（SOD） is a crucial antioxidant enzyme playing the first defense line in antioxidant pathways against reactive oxygen species in various organisms including marine invertebrates. There exist mainly two specific forms, Cu/Zn-SOD（SOD1） and Mn-SOD（SOD2）, in eukaryotes. SODs are known to be concurrently modulated by a variety of environmental stressors. By using central composite experimental design and response surface method, the joint effects of water temperature（18–34°C） and copper ion concentration（0.1–1.5 mg/L） on the total SOD activity in the digestive gland of Crassostrea ariakensis were studied. The results showed that the linear effect of temperature was highly significant（P〈0.01）, the quadratic effect of temperature was significant（P〈0.05）; the linear effect of copper ion concentration was not significant（P〉0.05）, while the quadratic effect of copper ion concentration was highly significant（P〈0.01）; the interactive effect of temperature and copper ion concentration was not significant（P〉0.05）; the effect of temperature was greater than that of copper ion concentration. The model equation of digestive gland SOD enzyme activity towards the two factors of interest was established, with R2 and predictive R2 as high as 0.961 6 and 0.820 7, respectively, suggesting that the goodness-offit to experimental data be very satisfactory, and could be applied to prediction of digestive gland SOD activity in C. ariakensis under the conditions of the experiment. Our results would be conducive to addressing the health of aquatic animals and/or to detecting environmental problems by taking SOD as a potential bioindicator.

Effects of phycocyanin on apoptosis and expression of superoxide dismutase in cerebral ischemia reperfusion injury

BACKGROUND ： The application of exogenous antioxidant is always the focus in the prevention and treatment of cerebral ischemia. Phycocyanin has the effects against oxidation and inflammation, but its role in the pathophysiological process of cerebral ischemia reperfusion injury still needs further investigation. OBJECTIVE： To observe the effects of phycocyanin on the expression of superoxide dismutase （SOD） apoptosis and form of the nerve cells in rats after cerebral ischemia reperfusion injury. DESIGN： A randomized control animal experiment SETTING ： Institute of Cerebrovascular Disease, Medical School Hospital of Qingdao University MATERIALS： Fifty-two healthy adult male Wistar rats of clean degree, weighing 220-260 g, were used. Phycocyanin was provided by the Institute of Oceanology, Chinese Academy of Sciences. METHODS： The experiments were carried out in Shangdong Key Laboratory for Prevention and Treatment of Brain Diseases from May to December 2005. ① All the rats were divided into three groups according to the method of random number table： sham-operated group （n=4）, control group （n=24） and treatment group （n=24）. Models of middle cerebral artery occlusion/reperfusion （MCAO/R） were established by the introduction of thread through external and internal carotid arteries in the control group and treatment group. After 1-hour ischemia and 2-hour reperfusion, rats in the treatment group were administrated with gastric perfusion of phy- cocyanin suspension （0.1 mg/g）, and those in the control group were given saline of the same volume, and no treatment was given to the rats in the sham-operated group. ②The samples were removed and observed at ischemia for 1 hour and reperfusion for 6 and 12 hours and 1, 3, 7 and 14 days respectively in the control group and treatment group, 4 rats for each time point, and those were removed at 1 day postoperatively in the sham-operated group. Forms of the nerve cells were observed with toluidine blue staining. Apoptosis after cerebral ischemia reperfusion was detected with TUNEL technique. SOD expression was detected with immunohistochemical technique.③ The intergroup difference was compared with the ttest. MAIN OUTCOME MEASURES： The apoptosis of the nerve cells and SOD expression were mainly observed in each group. RESULTS： Finally, 52 rats were involved in the analysis of results. ① Number of apoptotic cells： In the sham-operated group, a few apoptotic cells could be observed in brain tissue. The apoptotic cells at each time point in the control group and treatment group were obviously more than those in the sham-operated group （P 〈 0.05）. In the treatment group, the numbers of apoptotic cells at 12 hours, 1 and 3 days after reperfusion were significantly fewer than those in the control group, and those at 6 hours, 7 and 14 days were similar to those in the control group. ② Number of SOD positive cells： In the sham-operated group, there was weak expression of SOD in brain tissue, and the positive cells were extremely few, the positive cells at each time point were significantly more in the control group and treatment group than in the sham-operated group （P 〈 0.05）. In the treatment group, the numbers of positive cells at 6 and 12 hours, 1 and 3 days after reperfusion were significantly fewer than those in the control group, and those at 7-14 days were similar to those in the control group. ③ Cellular forms： In the control group, the karyopyknosis occurred in the nerve cells, which were irregularly distributed, nucleolus disappeared, and some scattered cell fragments were observed. The forms of the nerve cells in the treatment group were generally normal. CONCLUSION ： Phycocyanin plays a neuroprotective role in cerebral ischemia reperfusion injury by activating the SOD expression and inhibiting apoptosis.

Effect of N+ Beam Exposure on Superoxide Dismutase and Catalase Activities and Induction of Mn-SOD in Deinococcus Radiodurans

Though bacteria of the radiation-resistant Deinococcus radiodurans have a high resistance to the lethal and mutagenic effects of many DNA-damaging agents, the mechanisms involved in the response of these bacteria to oxidative stress are poorly understood. In this report, the superoxide dismutase (SOD) and catalase (CAT) activities produced by these bacteria were measured, and the change of SOD and CAT activities by 20 keV N+ beam exposure was examined. Their activities were increased by N+ beam exposure from 8x 1014 ions/cm2 to 6x1015 ions/cm2.The treatment of H2O2 and [ CHC13 +CH3 CH2OH ] and the measurement of absorption spectrum showed that the increase in SOD activity was resulted from inducible activities of MnSOD in D. radiodurans AS1.633 by N+ beam exposure . These results suggested that this bacteria possess inducible defense mechanisms against the deleterious effects of oxidization.

EFFECTS OF COMBINATION OF ACUPUNCTURE AND MOXIBUSTION WITH CHINESE DRUGS ON LIPIDS PEROXIDE AND ANTIOXIDASE IN PATIENTS OF VASCULAR DEMENTIA

In the present paper, blood lipids peroxide(LPO) level and activities of glutathione peroxidase(GSH-Px) and superoxide dismutase(SOD) were investigated before and after combined treatment of acupuncture and moxibustion and Chinese drugs in patients of vascular dementia(VD), and their results were compared with those in healthy persons with the similar ages to the patients. The results showed that the blood LPO level increased significantly, and the activities of SOD and GSH-Px reduced significantly in patients of VD as compared with those in the control group. Degrees of patient’s condition were related with amplitudes of the increase of LPO and the reduction of activities of GSHPx and SOD. Combined treatment of acupuncture and moxibustion and Chinese drugs could raise markedly activitles of blood GSH-Px and SOD, and lowered LPO level in the patients of VD, which are related to clinical therapeutic effects. It is considered that combination of acupuncture and moxibustion with Chinese drugs can increase the action of the antiperoxidative system in the patients of VD, exerting anti-peroxidative ability and clearing LPO and reducing the oxidative injury of the organism by oxygen free radical, which is one of mechanisms of combined treatment of acupuncture and moxibustion with Chinese drugs.

Mechanism of antagonistic effects of Andrographis paniculata methanolic extract against Staphylococcus aureus

Objective: To investigate the effects of Andrographis paniculata(Burm.f.) Wall. Ex Nees(A. paniculata) on expressions and activities of catalase, superoxide dismutase and alkylhydroperoxide reductase C in Staphylococcus aureus(S. aureus) with respect to its survival in vitro. Methods: Antioxidative property of methanolic leaves extract of A. paniculata(0.06 mg/m L). Minimum inhibitory concentration(MIC) was determined by its ability to reduce hydrogen peroxide(H_2O_2) toxicity against S. aureus ATCC 25923(3.8×10~8 cfu/m L). Effects of the extract on expressions of kat A(encoding catalase), sod A and sod M [encoding superoxide dismutases(SODs)], and ahp C [encoding alkylhydroperoxide reductase C(AhpC)] in S. aureuswere determined by RT-q PCR and corresponding enzyme activity assays were performed. Nitroblue tetrazolium reduction(NBT) assay was performed to determine effects of the extract on intracellular and extracellular levels of O_2-in S. aureus. Results: Cells challenged with 7.5 mmol/L H_2O_2 showed 0% survival in 30 min whereas 25% survived after treatment with the extract and H_2O_2. Cells that were treated with the extract alone had 43% survival in the same exposure period. Expressions of sod A and sod M genes in extract-treated cells were lowered 0.8-fold and 0.7-fold, respectively with decrease in total SOD activity of 26.8 U compared to untreated cells, 32.4 U(P<0.05). In contrast, extract-treated S. aureus cells showed 3.3-fold increase in kat A expression with corresponding increase in catalase activity of 1.828 U compared to untreated cells which was 1.248 U,(P<0.05). More profoundly, ahp C expression was increased 61-fold in extract-treated cells,(P<0.05) with corresponding increase in Ahp C activity of 0.018 U compared to untreated cells, 0.012U,(P<0.05). Extract-treated cells had significantly lower intra-and extracellular O_2-levels with absorbance readings(A_(575nm)) of 0.340 and 0.524 compared to untreated cells which were 0.516 and 0.928(P<0.05), respectively. Conclusions: Taken together these results suggest that the low MIC of A. paniculatamethanolic leaves extract(0.06 mg/m L) reduce H_2O_2 toxicity and more importantly, was in itself effectively inhibitory against S. aureus. Further, our observations suggest that a probable mode of its inhibitory mechanism against S. aureus is by reducing total SOD activity through downregulation of sod A and sod M expressions.

Effects of Shenmai Injection on Blood SOD Activity and MDA Level in Senile Patients with Coronary Heart Disease

In order to approach the effects of Shenmai Injection on SOD activity and MDA level in the senile patients with coronary heart disease, 48 cases, who had stenosis of over 70% in more than one branches of the coronary arteries, were assigned randomly into a treatment group (given Shenmai Injection plus the routine treatment) and a control group (given the routine treatment only). The superoxide dismutase (SOD) activity and malondialdehyde (MDA) level were determined before treatment and at the end of a 3-week treatment. The results showed that in the treatment group, the SOD activity was significantly increased (P＜0.05) and the MDA level markedly decreased (P＜0.01) in the treatment group. It can be concluded that Shenmai Injection may enhance the antioxidant ability of the senile patients with coronary heart disease.

EFFECTS OF CYPROHEPTADINE ON PLASMA SUPEROXIDE DISMUTASE ACTIVITY AND MALONDIALDEHYDE CONTENT IN RABBITS WITH HEMORRHAGIC SHOCK

Profound hemorrhagic shock was produced in thirty rabbits by exsanguination via the carotid artery until blood pressure (BP) reached 5.3 kPa (40 mmHg) and was sustained for a period of 90 minutes. The rabbits were equally divided into cyproheptadine (Cyp) treated group and control group. Blood samples 30 minutes after liquid and blood infusion and administration of Cyp (10 mg / kg) were collected from the carotid artery, and the plasma superoxide dismutase (SOD) activity and malondialdehyde (MDA) content measured. The results showed that Cyp remarkebly enhanced the plasma SOD activity (2462 338 vs 1955- 596, P<0.01) and reduced MDA content (2.68- 0.24 vs 3.20-0.49, P<0.01). We believe that the in crease of O2 production plays an important role in the develop-ment of shock, the single blood and liquid infusion can not significantly improve the shock conditions. Scavenging oxygen free radicals and alleviating cellular damage and multiple or gan failure are the possible mechanisms of cyproheptadine anti-shock effect.

Assessment of the Heavy Metals and Natural Radioactivity in Phosphate Mines and Occupational Health Effects at Some Egyptian Regions

In this work, the specific activities of natural radionuclides, namely 238U series, 232Th series and 40K, have been measured in collected sedimentary phosphate deposits samples from El-Hamraween, El-Quser and Safaga phosphate mines in Egypt. HPGe γ-spectrometry was used. This study was undertaken to estimate the radiation hazard indices in phosphate mining at the studied mines on their occupational workers, to establish correlation relationships between the some measured heavy metals such as As, Cd and Pb in blood workers and their concentration in phosphate rock ores and to determinate the biomarkers in the blood workers such as malondialdehyde (MDA) and superoxide dismutase (SOD). The phosphate mine sample of El-Hamrawein has the lowest activity concentration of 226Ra, 232Th and 40K in comparison to the phosphate mine samples of El-Quseir and Safaga (El-Hamrawein kg-1, 122.4 to 188.3 Bq·kg-1 and 115.4 to 165.8 Bq·kg-1 for Safaga, El-Quseir and El-Hamrawein, respectively. For 232Th activity concentrations varied from 135.6 to 212.3 Bq·kg-1, 112.8 to 167.4 Bq·kg-1 and 132.8 to 188.6 Bq·kg-1 for Safaga, El-Quseir and El-Hamrawein, respectively. For 40K activity concentrations varied from 225.2 to 312.8 Bq·kg-1, 168.7 to 268.9 Bq·kg-1 and 95.2 to 155.8 Bq·kg-1 for Safaga, El-Quseir and El-Hamrawein, respectively. The workers of old ages have higher concentration of the investigated heavy metals than those of young ages. There is a good relation between the concentration of the investigated metals in phosphate mine samples and their concentration in blood of the occupational workers in these mines.

Substituent Effect on Proton Affinity of Imidazole in Cu,Zn-Superoxide Dismutase

To investigate whether the proton-accepting ability of imidazole in Cu,Zn-superoxide dismutase （SOD） was possibly modulated by Zn（Ⅱ） or not, the proton affinity （Ap） of N^3 in imidazole group was calculated by density functional theory （DFT） with B3LYP functional. It was found that Zn（Ⅱ） attenuates the Ap, because of its electron-withdrawing effect, while the three ligands connected with Zn（Ⅱ） （residues of two His and one Asp） exert an opposite effect, owing to their electron-donating ability. This finding suggested that the three ligands should play a role in the normal function of Cu,Zn-SOD and should be taken into consideration in the future study.

枳椇子黄酮的含量测定及其抗氧化作用的分子机制

为了测定枳椇子黄酮的含量并探究其抗氧化作用的潜在机制。本试验以枳椇子为原料,采用醇提法提取其黄酮成分,通过紫外-可见分光光度法测定总黄酮含量,并进一步采用CavityPlus和分子对接分析枳椇子黄酮与超氧化物歧化酶(SOD)相互作用的位点、氨基酸残基和化学键。结果显示:枳椇子总黄酮含量为8.23 mg/g;枳椇子黄酮主要成分可能结合于SOD同源二聚体交界面且靠近锌离子的一凹陷区域,其5个主要成分,即双氢杨梅素、双氢槲皮素、槲皮素、双氢山萘酚和山萘酚与SOD的结合能范围为-8.5~-8.3 kcal/mol,且上述5个主要成分均与SOD的A链的Gly147和B链的Gly147有直接作用,并通过氢键、疏水作用力和静电作用力等非共价键相连。结果表明,枳椇子富含黄酮,可通过其黄酮成分与SOD直接结合以增加SOD活性,本试验为枳椇子抗氧化作用机制的研究及其产品的开发提供了科学依据。

An Experimental Study on Drugs for Improving Blood Circulation and Removing Blood Stasis in Treating Mild Chronic Hepatic Damage

Large and small doses of drugs for improving blood circulation and removing blood stasis were used in model rats to treat mild chronic hepatic damage induced by carbon tetrachloride (CCl4). The results show that large dose of Dang Gui (当归 Radix Angelicae Sinensis) and Dan Shen (丹参 Radix Salviae Miltiorrhizae) (drugs for regulating blood flow) and small dose of Yu Jin (郁金 Radix Curcumae) and Niu Xi (牛膝 Radix Achyranthis Bidentatae) (drugs for activating blood flow) can significantly elevate the activity of SOD (P<0.05) and/or lower the T/K ratio, markedly reduce the MDA content (P<0.05 or P<0.01) and significantly decrease the activities of ALT and AST (P<0.05 or P<0.01), demonstrating that these drugs are effective in combating oxygen free radicals (OFR) in chronic liver damage. On the contrary, large dose of Tu Bie Chong (土鳖虫 Eupolyphaga seu Steleophaga) and E Zhu (莪术 Rhizoma Curcumae) (drugs for removing blood stasis) tend to increase the ALT and AST (P<0.05) activities. The results suggest that the synergism of elevation of the SOD activity and reduction of T/K ratio contributes to the action of drugs for improving blood circulation and removing blood stasis in combating the liver damage induced by CCl4.

超氧化物歧化酶在糖尿病视网膜病变中的研究进展

糖尿病视网膜病变(DR)是糖尿病并发症中最常见的微血管疾病,是导致工作年龄人群视力损害和失明的主要原因。高血糖状态加剧氧化应激反应,释放大量的活性氧自由基,使组织细胞中的蛋白质、DNA或者RNA损伤,从而导致细胞死亡,氧化应激被认为是DR发生发展的重要因素之一。抗氧化防御系统是维持氧化还原稳态的关键组成部分,超氧化物歧化酶(SOD)是一种主要的抗氧化酶,维持抗氧化酶库中的第一道防线。在哺乳动物中存在着三种SOD的同工酶,主要通过加速SOD的突变反应来保护细胞免受超氧化物的损伤,调节抗氧化物酶SOD水平可能会延缓DR的发生发展。目前DR的发病作用机制尚不明确,本文就抗氧化物酶SOD在DR疾病中对周细胞、神经节细胞的保护作用研究进展进行综述。

刺五加精制多糖对尼古丁诱导的学习记忆障碍小鼠的影响

目的观察刺五加精制多糖(ASPS)对尼古丁诱导的学习记忆障碍小鼠的影响。方法选取6周龄小鼠96只,雌雄各半,将其分为2批进行动物试验,即水迷宫试验和新物体识别试验。每批按小鼠体质量随机分为6组:空白组、模型组、阳性药物组、ASPS高剂量组、ASPS中剂量组、ASPS低剂量组。除空白组外,其余5组连续7 d每天皮下注射尼古丁0.5 mg/kg,制备尼古丁记忆障碍模型。第7天注射尼古丁24 h后,阳性药物组灌胃吡拉西坦800 mg/kg,ASPS高剂量组、ASPS中剂量组、ASPS低剂量组连续7 d分别灌胃ASPS 270、90、30 mg/kg。通过水迷宫试验和新物体识别试验分别检测小鼠的学习记忆能力。测试结束后,检测血清中超氧化物歧化酶(SOD)活性和海马组织中五羟色胺(5-HT)含量。结果新物体识别试验结果显示,ASPS高、中、低剂量组辨别指数高于模型组,差异有统计学意义(P<0.01或P<0.05)。水迷宫试验结果显示,与模型组比较,ASPS高、中剂量组小鼠空间搜索试验中找到平台的时间缩短,差异有统计学意义(P<0.05);定位航行试验中,ASPS高剂量组小鼠平台进入次数多于模型组,差异有统计学意义(P<0.05);ASPS高、中剂量组小鼠Ⅲ象限路程比例高于模型组,差异有统计学意义(P<0.05)。ASPS高、中、低剂量组SOD活性高于模型组,差异有统计学意义(P<0.01);小鼠海马组织含量测定显示,ASPS高、中剂量组小鼠5-HT含量高于模型组,差异有统计学意义(P<0.01或P<0.05)。结论ASPS能显著提高尼古丁戒断小鼠的学习记忆能力,减轻海马神经递质的损伤,调节体内氧化应激能力,其机制可能与提高机体抗氧化能力、调节海马神经递质水平有关。

视黄酸相关孤儿受体α对阿霉素诱导心肌损伤的改善作用及机制研究

目的:探讨视黄酸相关孤儿受体α(RORα)对阿霉素(DOX)诱导的心肌损伤的改善作用及机制。方法:采用尾静脉注射RORα过表达慢病毒建立心肌RORα高表达模型。随机将小鼠分为对照组(NC组)、RORα过表达组、DOX组和RORα过表达+DOX组,每组20只。其中,DOX组和RORα过表达+DOX组一次性给予15 mg/(kg·d)DOX腹腔注射,NC组和RORα过表达组给予腹腔注射同等体积0.9%氯化钠溶液。2周后,采用超声检测左心室射血分数(LVEF)和左心室短轴缩短率(LVFS);采用相应试剂盒检测血浆血浆肌酸激酶(CK)和乳酸脱氢酶(LDH)活性;采用TUNEL法检测小鼠心肌凋亡情况;采用电镜观察心肌线粒体形态;采用比色法检测心肌活性氧簇(ROS)水平;采用Western blot检测RORα和锰超氧化物歧化酶(MnSOD)蛋白表达水平。结果:与NC组比较,DOX组LVEF和LVFS降低,CK、LDH活性增加,心肌细胞凋亡增加,心肌ROS水平增加,MnSOD蛋白表达降低(均P<0.05),并且心肌线粒体发生损伤。与DOX组比较,RORα过表达+DOX组LVEF和LVFS增加,CK、LDH活性下降,心肌细胞凋亡减少,心肌ROS水平降低,MnSOD蛋白表达增加(均P<0.05),并且心肌线粒体损伤有明显改善。结论:在DOX诱导的心肌损伤中,RORα可能通过调控MnSOD表达发挥改善心肌的作用。

温度和盐度对珍珠龙胆石斑鱼血清免疫因子活性的联合效应

【目的】研究环境因子温度、盐度同时变化对珍珠龙胆石斑鱼(Epinephelus fuscoguttatus♀×Epinephelus lanceolatus♂)血清免疫因子活性的影响,探讨机体抵御温盐变化的生理生化反应规律。【方法】在温度14~36℃、盐度5~45条件下,每个因子各取3个编码水平,设计中心复合实验,构建温度、盐度对珍珠龙胆石斑鱼幼鱼血清过氧化物歧化酶(SOD)活性、溶菌酶(LZM)活性、补体(C3、C4)含量影响的二次回归模型,分析温度、盐度对上述指标的一次、二次效应,采用响应曲面分析法分析温度、盐度对上述指标的联合效应。【结果】构建的温度与盐度对血清免疫因子影响的二次回归模型方程拟合度高;温度、盐度的一次效应、二次效应对于珍珠龙胆石斑鱼幼鱼血清LZM活性、补体C3含量、补体C4含量的影响极为显著(P<0.01),温度的一次效应对于血清SOD活性的影响极为显著(P<0.01);在实验设定的温度、盐度范围内,温度、盐度对血清LZM活性、补体C4含量存在显著的交互效应(P<0.05)。【结论】温度、盐度可显著影响血清免疫因子的活性,并对LZM活性、补体C4含量存在显著的协同效应,表明温度、盐度是影响珍珠龙胆石斑鱼免疫的重要环境因子。

高强度阿托伐他汀致肝损伤小鼠肠道菌群的改变及其与肝脏CYP2E 1的关系

目的探讨高强度阿托伐他汀(ATO)导致肝损伤小鼠肠道菌群的改变及其与肝组织中CYP2E1的关系。方法C57BL/6小鼠40只,按照处理方式不同分为4组,每组10只,低强度ATO组(ATO-L组)、中强度ATO组(ATO-M组)、高强度ATO组(ATO-H组)小鼠每天分别灌胃含有10、20、30 mg/kg ATO的生理盐水1 mL,对照组(CON组)小鼠每天灌胃等量生理盐水,持续4周。HE染色后透射电镜下观察各组小鼠肝脏病理状态,检测各组小鼠血清中ALT、AST、TNF-α、IL-6和IL-10水平以及肝脏组织中SOD活力、CYP2E 1的mRNA水平,采用16SrDNA测序法分析小鼠新鲜粪便中肠道菌群分布,将差异有显著意义的菌属的相对丰度与肝脏组织中CYP2E 1 mRNA水平及SOD活力进行相关性分析。结果经HE染色及透射电镜下观察显示,ATO-M组、ATO-H组小鼠肝脏均出现不同程度的损伤现象;各组小鼠血清中ALT、AST、IL-6、TNF-α和肝脏组织中SOD活力差异有显著性(F=4.57~7.74,P<0.05)。ATO-H组小鼠肠道菌群稳态失衡,ATO-H组拟杆菌门、厚壁菌门、变形菌门和脱铁杆菌门的相对丰度与CON组比较,差异有显著性(t=2.89~5.22,P<0.05);两组紫单孢菌科、普氏菌科、乳杆菌科、毛螺菌科、螺杆菌科的相对丰度差异有显著性(t=2.45~5.46,P<0.05);两组螺杆菌属、拟普雷沃菌属、普氏菌属和乳杆菌属的相对丰度差异具有显著性(t=2.46~7.41,P<0.05)。乳杆菌属的相对丰度与肝脏组织SOD活力呈正相关(r=0.48,P<0.05),与肝组织中CYP2E 1的mRNA水平呈负相关(r=-0.62,P<0.05)。结论高强度他汀类药物可导致小鼠肠道菌群稳态失衡,抗氧化应激能力下降,肠道菌群乳杆菌属的减少可能会促进肝脏的氧化应激反应。

男性缺血性卒中患者发病早期血清褪黑素、超氧化物歧化酶水平预测病情转归的价值

目的 分析男性急性缺血性卒中(AIS)患者发病早期血清褪黑素、超氧化物歧化酶(SOD)水平预测病情转归的价值。方法 回顾性选取2021年10月至2022年10月由南华大学附属第二医院神经内科收治的206例男性AIS患者作为研究对象,对其一般资料、入院当日血清褪黑素、SOD水平进行分析,于发病14 d时根据患者美国国立卫生研究院卒中量表(NIHSS)评分和改良Rankin量表(mRS)评分的治疗效果和伤残程度进行评价。将治疗效果为治愈、显效或有效的患者列为有效组(n=150),将治疗效果为无效或恶化的患者列为无效组(n=56)。将伤残等级为无伤残、轻度伤残或中度伤残的患者列为非重残组(n=158),将伤残等级为重度伤残或严重伤残的患者列为重残组(n=48)。分析血清褪黑素、SOD水平与治疗效果及伤残程度的相关性及预测价值。结果 不同治疗效果及伤残程度患者入院时血清褪黑素、SOD水平的整体差异均有统计学意义(P<0.05),其中,治疗效果为无效患者与治疗效果为恶化患者的血清褪黑素、SOD水平比较,差异无统计学意义(P>0.05),其余各组之间比较,患者的血清褪黑素、SOD水平比较,差异均有统计学意义(P<0.05)。Logistic多元回归模型进行分析结果显示,AIS患者的治疗效果和伤残程度均与入院时的血清褪黑素、SOD水平具有相关性(P<0.05)。受试者工作特征曲线分析结果显示,血清褪黑素、SOD水平预测AIS患者治疗效果及伤残程度的曲线下面积差异均有统计学意义(P<0.05)。结论 男性AIS患者病程早期血清褪黑素、SOD水平的下降与治疗无效和重伤残有关,这两种血清学指标可用于辅助预测男性AIS患者的病情转归。

铅胁迫对3种藓类植物抗氧化酶活性的影响

采用水培实验研究了重金属Pb对3种藓类植物尖叶拟船叶藓（Dolichomitriopsis diversiformis）、湿地匍灯藓（Plagiomnium acutum）和匍枝青藓（Brachythecium procumbens）的抗氧化酶（SOD、POD和CAT）活性的影响。结果表明，（1）在1～200mg·L^-1的铅胁迫浓度范围内，Pb对3种藓类植物的SOD活性均具有显著的促进作用，对Pb胁迫的种间敏感性差异为尖叶拟船叶藓〉湿地匍灯藓〉匍枝青藓；（2）POD活性对Pb胁迫的反应趋势有一定差别，尖叶拟船叶藓和匍枝青藓的POD活性随Pb浓度的增加先升后降，湿地匍灯藓的POD活性变化较为平缓，种间敏感性差异为匍枝青藓〉尖叶拟船叶藓〉湿地匍灯藓；（3）在100mg·L^-1时Pb对湿地匍灯藓CAT活性表现为显著促进作用外，其余在低浓度下显示无显著影响，在高浓度下表现为抑制效应，种间敏感性差异为尖叶拟船叶藓〉匍枝青藓〉湿地匍灯藓。3种藓类植物的抗氧化酶体系中对Pb胁迫的抵抗起关键作用的是SOD，可作为藓类植物受Pb胁迫的敏感生理指标。3种植物中对Pb胁迫的反应较为敏感的是尖叶拟船叶藓。

刺梨多糖对衰老小鼠体内抗氧化能力的影响

目的探讨刺梨多糖(RRTP)对衰老小鼠体内抗氧化能力的影响。方法用D-半乳糖所致衰老小鼠作为实验对象,灌胃给予RRTP100,200,400mg/kg.d,47d后观察其对小鼠血浆、肝脏、脑组织中超氧化物歧化酶(SOD)、丙二醛(MDA)、过氧化氢酶(CAT)含量的影响。结果衰老小鼠血浆、肝脏、脑组织匀浆中SOD、CAT含量均显著降低,MDA含量显著升高;200,400mg/kg·dRRTP可以提高衰老小鼠血浆、肝脏、脑组织中SOD、CAT含量,降低MDA含量,与模型组比较,差异有显著性。结论RRTP可以剂量依赖性地提高衰老小鼠体内抗氧化能力。

地黄连作的生理生态特性

选择具有典型连作障碍效应的药用植物地黄(Rehmannia glutinosa)为试验材料,以正茬地黄为对照,研究连作条件下地黄植株的生理生态特性变化。结果表明,该试验条件下地黄的连作障碍效应起始于苗期,在栽种后60天时,连作引起植株细胞膜质过氧化作用,使膜的正常结构和功能受到损伤;重茬地黄的光合速率(Pn)、气孔导度(Gs)和胞间CO2浓度(Ci)显著低于对照,而气孔限制值(LS)33.97%,显著高于对照,同期重茬地黄叶绿素含量(Chl)也开始显著低于对照。相关分析表明,Pn与Gs、Chl含量相关(相关系数分别为0.977和0.814)。对植株叶片叶肉细胞的电镜观察显示,连作条件下地黄光合细胞结构在其生长中期开始发生变化。因此,在地黄生长早期由于(连作)环境胁迫植株叶片细胞内活性氧、自由基积累所带来的膜结构损伤,导致了叶绿素含量的降低,而气孔关闭以及叶绿素含量的降低共同造成连作地黄早期光合能力降低,生长受阻,从而表现出明显的障碍效应。