酵母源金属硫蛋白(MT-2)对慢性汞中毒小鼠肝脏损伤的修复作用

探讨具有自主知识产权酵母源金属硫蛋白(MT-2)对慢性汞中毒小鼠肝脏损伤的修复作用。让实验小鼠自由饮用氯化汞溶液构建汞中毒模型,以二巯基丙磺酸钠(DMPS)为对照,低、中、高3种剂量酵母源MT-2溶液连续灌胃汞中毒小鼠28 d,然后测定实验小鼠体重、血液生化指标、肝脏汞含量及血清谷丙转氨酶(ALT)和谷草转氨酶(AST)含量,并取肝脏制作HE病理学组织切片,观察肝脏组织病变程度。与模型组小鼠相比,正常组小鼠与各灌胃给药组小鼠体重均高于模型组小鼠,差异不显著(P0.05)。相较于模型组小鼠,各给药组小鼠血液白细胞、红细胞、血小板计数及血红蛋白含量均有明显的回升,其中高剂量的酵母源金属硫蛋白对于血常规4项指标呈现显著的改善优势(P0.05)。各给药组小鼠肝脏汞含量及血清ALT、AST含量均显著低于模型组小鼠(P0.05)。病理学切片观察显示,酵母源MT-2可改善慢性汞中毒小鼠的肝脏损伤状况,可使肿胀肝脏细胞恢复正常形态,其改善效果与剂量呈正相关,且高剂量给药组的改善状态优于DMPS给药组。酵母源MT-2对慢性汞中毒小鼠肝脏损伤具有一定的修复作用,且高剂量酵母源MT-2对汞中毒小鼠肝脏损伤的修复效果明显优于DMPS。     

酵母源金属硫蛋白对慢性汞中毒小鼠氧化损伤的修复作用

探讨具有自主知识产权的两种酵母源金属硫蛋白（metallothionein,MT）亚型（MT-1和MT-2）对慢性汞中毒小鼠氧化损伤的修复作用。实验小鼠经氯化汞染毒,连续灌胃两种酵母源MT及二巯基丙磺酸钠（dimercaptopropansulfonate sodium,DMPS）28 d后测定小鼠体质量、全血汞含量及血清超氧化物歧化酶（superoxide dismutase,SOD）、谷胱甘肽过氧化物酶（glutathione peroxidase,GSH-Px）活力,丙二醛（malondialdehyde,MDA）含量及机体总抗氧化能力（total antioxidative capacity,T-AOC）。与正常对照组小鼠相比,模型对照组小鼠体质量显著下降（P＜0.05）,灌胃给药28 d后,两种酵母源MT亚型高剂量组小鼠体质量显著升高（P＜0.05）;各给药组小鼠血液、肝脏及肾脏汞含量显著低于模型对照组（P＜0.05）,两种酵母源MT亚型高剂量组的排汞效果显著优于DMPS组（P＜0.05）;各给药组小鼠血清中GSH-Px、SOD活力和MDA水平及总抗氧化能力接近正常对照组小鼠水平（P＞0.05）,其中酵母源MT高剂量组的作用效果最佳,且在改善机体T-AOC方面的效果优于DMPS组（P＜0.05）,酵母源MT-1亚型升高小鼠血清SOD活力和降低血清MDA含量的作用效果明显好于酵母源MT-2亚型。两种酵母源MT对慢性汞中毒小鼠具有良好的氧化损伤保护作用及排汞效果。     

酵母源金属硫蛋白对慢性汞中毒小鼠排汞及肾脏损伤的修复作用

探讨具有自主知识产权的酵母源金属硫蛋白(MT-1、MT-2)对慢性汞中毒小鼠排汞及汞致肾脏损伤修复作用。SPF级昆明雄性种鼠经氯化汞染毒,灌胃酵母源金属硫蛋白及二巯基丙磺酸钠(DMPS)28 d后测定小鼠体质量、肾脏湿重及肾指数、血液及肾脏汞离子含量、血清尿素氮(BUN)、肌酐(CREA)指标水平,并取肾脏组织制作HE病理学染色切片,观察肾脏病变程度及灌胃药物对肾脏组织的修复情况。试验结果表明,相较于正常对照组,模型对照组小鼠体质量显著下降(P0.05),肾指数、血液及肾脏汞含量、BUN及CREA水平显著升高(P0.05)。HE染色切片显示模型对照组小鼠肾脏组织出现肾小球及系膜细胞增生,并伴有大量炎性细胞浸润及组织坏死现象。灌胃给药28 d后,各灌胃给药组小鼠体质量较模型对照组显著增加(P0.05),酵母源金属硫蛋白高剂量及DMPS给药组小鼠肾指数、血液及肾脏汞含量、BUN及CREA水平显著下降(P0.05),且病理学切片显示酵母源金属硫蛋白高剂量给药可修复小鼠肾脏受损组织细胞,水肿增生及坏死现象明显减轻。两种酵母源金属硫蛋白对慢性汞中毒小鼠具有良好的排汞及修复汞致小鼠肾脏损伤的作用。     

酵母源金属硫蛋白排汞及对汞致肝脏及机体氧化损伤的修复作用

目的:探讨两种酵母源金属硫蛋白(metallothioneins,MT)-1、MT-2对氯化汞急性汞中毒小鼠排汞及对汞致肝脏及机体氧化损伤的修复作用。方法:氯化汞急性汞中毒小鼠模型通过颈部皮下注射氯化汞生理盐水溶液构建,急性汞中毒小鼠经连续灌胃二巯基丙磺酸钠(dimercaptopropansulfonate sodium,DMPS)及不同剂量(0.16、0.40、0.80 mg/(kg·d))酵母源MT 14 d后,测定小鼠体质量、肝脏脏器系数、血液及肝脏Hg~(2+)的含量、血清谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活力、超氧化物歧化酶(superoxide dismutase,SOD)活力、机体总抗氧化能力(total antioxidative capacity,T-AOC)及丙二醛(malondialdehyde,MDA)含量和两项肝功能指示指标:谷丙转氨酶(alanine aminotransferase,ALT)及谷草转氨酶(aspartate transaminase,AST)活力。结果:相较于正常组小鼠,模型组小鼠体质量下降、肝脏脏器系数上升,差异具有统计学意义(P0.05);血液及肝脏Hg~(2+)含量显著上升(P0.05);血清GSH-Px、SOD活力及T-AOC显著降低(P0.05),MDA含量显著升高(P0.05);两项肝功能指标ALT及AST活力显著升高(P0.05)。经灌胃给药处理后,与模型组小鼠相比,酵母源MT中、高剂量处理组及二巯基丙磺酸钠阳性对照组小鼠体质量均显著上升(P0.05),并与正常组小鼠无显著性差异(P0.05);各给药处理组小鼠脏器系数均较模型组小鼠显著下降(P0.05)且呈一定的剂量-效应关系。各灌胃给药处理组小鼠血液及肝脏Hg~(2+)含量均不同程度下降;血清GSH-Px、SOD活力及T-AOC均不同程度回升,MDA含量及两项肝功能指标ALT及AST活力均不同程度降低。在0.16~0.80 mg/kg剂量范围内,高剂量酵母源MT给药效果最佳,与其他灌胃给药处理组差异显著(P0.05)。结论:两种酵母源MT对急性汞中毒小鼠具有良好的结合机体内游离Hg~(2+)及修复肝脏损伤及机体氧化损伤作用,且作用效果与给药剂量呈正相关。     

酵母源金属硫蛋白对慢性铅中毒小鼠排铅及肝脏保护作用

探讨具有自主知识产权酵母源金属硫蛋白(MT)对慢性铅中毒小鼠的排铅及肝损伤保护作用。以二巯基丁二酸(DMSA)与动物源金属硫蛋白(兔肝Zn-MT)为对照,醋酸铅溶液致慢性铅中毒小鼠连续灌胃给予MT 35 d后,测定小鼠体重、血铅、部分血常规及肝功能指标水平,观察小鼠肝组织病变程度。与模型组比较,MT处理组小鼠体重无显著变化(P0.05);高剂量MT处理组小鼠血铅含量显著下降(P0.05),白细胞、红细胞平均体积及血红蛋白水平显著升高(P0.05),但各中毒组小鼠粒细胞计数水平无显著差异性(P0.05);各给药组小鼠GPT水平均显著下降(P0.05),同时高剂量MT处理组小鼠GOT水平均显著下降(P0.05),小鼠肝组织病变程度明显改善,其改善程度优于DMSA组。两种酵母源金属硫蛋白对慢性铅中毒小鼠均具有明显的排铅及肝脏保护作用,作用效果类似于动物源金属硫蛋白。     

酵母源金属硫蛋白对铅致肾脂质过氧化损伤的拮抗作用

探讨具有自主知识产权酵母源金属硫蛋白(MT)对铅致小鼠肾脂质过氧化损伤的拮抗作用。小鼠经醋酸铅染毒,连续灌胃给予MT 30 d后,测定小鼠体重、肾铅、丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、血清尿素氮(BUN)与血清肌酐(Cr)水平,观察小鼠肾组织病变程度。正常对照组与各给药组小鼠体重显著高于模型对照组(P0.05),各给药组小鼠肾脏铅水平均显著低于模型对照组(P0.05),其中MT-Ⅰ高剂量组小鼠肾脏铅水平下最低(P0.05);MT组小鼠血清BUN与Cr水平显著低于模型对照组,降低程度与剂量呈正相关,MT-Ⅰ高剂量组小鼠BUN水平显著低于其它给药组(P0.05),Cr水平与MT-Ⅱ高剂量组小鼠水平无显著差异(P0.05);MT高剂量组小鼠MDA、SOD及GSH-Px改善程度最好,且优于DMSA处理组(P0.05),其中MT-Ⅰ高剂量组小鼠脂质过氧化状态恢复最好,和正常组无显著差异(P0.05)。两种酵母源金属硫蛋白对铅染毒小鼠均具有明显拮抗肾脂质过氧化损伤作用,其中MT-Ⅰ亚型效果最好。     

芸豆芽菜多酚对氧化损伤小鼠体内抗氧化及肝脏损伤修复作用

本实验探究了芸豆芽菜多酚对D-半乳糖造模的氧化损伤小鼠体内抗氧化及肝脏损伤修复作用。腹腔注射D-半乳糖溶液构建氧化损伤小鼠模型,经连续灌胃不同剂量(20、40、60 mg/(kg·d))芸豆芽菜多酚28 d后测定小鼠体质量、肝脏脏器系数、血清超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)、谷丙转氨酶(alanine aminotransferase,ALT)、谷草转氨酶(aspartate transaminase,AST)活力及丙二醛(malondialdehyde,MDA)含量并取肝脏制作苏木精-伊红染色切片,观察小鼠肝脏损伤及修复状况。与模型对照组小鼠比较,各灌胃给药组小鼠体质量及肝脏脏器系数无显著性差异(P0.05),芸豆芽菜多酚中、高剂量组小鼠血清SOD、GSH-Px活力显著上升(P0.05),MDA含量显著下降(P0.05),肝脏功能指示指标ALT与AST活力显著下降(P0.05),且综合肝组织病理学染色切片结果观察发现芸豆芽菜多酚可使肿胀的肝细胞恢复正常形态,并可减少胞间出血点及炎性细胞浸润现象,且作用效果与剂量呈正相关。     

植物乳杆菌Z3对有机磷导致慢性中毒小鼠的解毒作用

该研究建立了慢性有机磷中毒小鼠模型,灌胃植物乳杆菌30 d后,测定小鼠脑和血胆碱酯酶（ChE）活性、脑组织活性氧（ROS）含量、肝脏和血清总超氧化物歧化酶（T-SOD）活性、丙二醛（MDA）含量,并进行肝、脑组织病理学检查,评估植物乳杆菌对慢性有机磷中毒小鼠的解毒效果。结果表明,与模型对照组相比,灌胃植物乳杆菌使慢性有机磷中毒小鼠的ChE、T-SOD活性升高,在血的ChE,高剂量组ChE活性较模型组提高了36.13%,脑组织高剂量组ChE较模型组提高了81.13%,血清T-SOD高剂量组较模型组提高了56.93%,脑组织的T-SOD高剂量组较模型组提高了65.14%;MDA和ROS的含量下降,血清的MDA高剂量组比模型组低28.91%,肝组织的T-SOD高剂量组比模型组低16.46%,脑组织的ROS模型组ROS比高剂量组高15.92%。在灌胃后,肝细胞损伤程度明显减轻;脑神经细胞、神经元和胶质细胞形态恢复正常,细胞排列较整齐。由此得出,灌胃植物乳杆菌可部分修复慢性有机磷农药中毒引起的机体损伤,具有一定的解毒作用。     

葛枳口腔崩解片对酒精性肝损伤小鼠的保护作用

探讨葛枳口腔崩解片对醉酒小鼠的解酒作用及对酒精性肝损伤小鼠的保肝作用的影响。抗醉酒研究:造模后采用葛枳口腔崩解片高、中、低剂量组进行灌胃干预,以纯净水作为对照,记录翻正反射消失和恢复时间。保肝作用研究:除正常组灌胃纯净水外、其余各组每天灌胃56度白酒,30 min后除空白组和模型组灌胃纯净水外,阳性药物及高、中、低剂量组灌胃各药物,连续10 d。测量小鼠的体重变化并计算其肝脏系数,检测血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)及肝脏组织中超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽(GSH)含量。与模型组相比,药物高剂量组将小鼠醉酒时间延长了6 min,醒酒时间缩短了122.94 min(p0.01),药物组可不同程度的增加小鼠体重并降低肝脏质量指数。与正常组比,模型组血清ALT含量增加了99.53 IU/L,AST含量增加了48.03 IU/L,肝组织中MDA升高了9.45 nmol/mg,肝组织中GSH含量降低了55.87 nmol/g,SOD含量降低了51.13 U/mg (p0.05)。与模型组比,药物各剂量组可降低血清ALT、AST及肝组织中的MDA含量,升高肝脏GSH、SOD含量(p0.05),结果呈剂量依赖关系。由此可知,葛枳口腔崩解片具有解酒保肝作用。     

苦菜茶总黄酮对小鼠酒精性脂肪肝的保护作用

探讨苦菜茶总黄酮对小鼠慢性酒精性脂肪肝的保护作用。采用酒精灌胃小鼠,建立慢性酒精性脂肪肝模型。通过不同剂量苦菜茶总黄酮灌胃12 周后,测定小鼠体质量、肝脏质量,血清谷丙转氨酶（alanineaminotransferase,ALT）、谷草转氨酶（aspartate transaminase,AST）活力,甘油三酯（triglyceride,TG）、总胆固醇（total cholesterol,TC）含量,肝脏丙二醛（malondialdehyde,MDA）、谷胱甘肽（glutathione,GSH）含量和超氧化物歧化酶（superoxide dismutase,SOD）活力,以及白细胞介素-1β（interleukin-1β,IL-1β）、肿瘤坏死因子-α（tumor necrosis factor-α,TNF-α）含量;观察肝脏病理变化。结果表明,与模型组比较,苦菜茶总黄酮剂量组血清ALT、AST活力和TG、TC含量,肝脏MDA、IL-1β、TNF-α含量都不同程度地降低,肝脏SOD活力,GSH含量则有所上升,肝脏肿大有一定程度的减轻,说明苦菜总黄酮对慢性酒精性脂肪肝小鼠的肝脏有一定的保护作用。     

Mercury residues in free-grazing cattle and domestic fowl form the artisanal gold mining area of Geita district,Tanzania

Environmental contamination with mercury from artisanal gold mines in Tanzania has been widely reported. People living around mining villages keep domestic animals which are allowed to feed freely in mercury-contaminated areas. This study investigated Hg accumulation in the liver and muscle tissue of cattle and domestic fowl reared in mining villages. Total mercury levels up to 436 and 820 µg/kg wet weight were found in liver samples taken from cattle and domestic fowl, respectively. Significantly higher mercury concentrations were found in liver samples collected at mining villages (p < 0.05) than those taken from the reference area. While mercury concentrations in liver samples exceeded the acceptable maximum concentrations for humans set in the Netherlands and Poland, the Hg concentrations in muscle were below the limits of most countries. It is recommended that the keeping of freely grazing cattle and domestic fowl in or around artisanal gold mines should be avoided.     

广东沿海两地海水鱼总汞与甲基汞的相关性分析

本研究以粤东和粤西两个渔村为研究区域,以两地20种主产海水鱼为研究对象,开展了海水鱼总汞和甲基汞的污染调查研究。通过直接测汞仪法和高效液相色谱-在线紫外消解-原子荧光光谱法研究了卵形鲳鯵、多鳞鱚和马鲛鱼等20种133尾海水鱼肌肉组织的总汞(total mercury,T-Hg)和甲基汞(methyl mercury,Me Hg)的总量与比值,结果显示:粤东某渔村海水鱼总汞含量为15.35~201.68 ng/g,甲基汞含量为8.32~200.20 ng/g,甲基汞含量所占总汞含量的比例平均为72.93%;粤西某渔村海水鱼总汞含量为11.32~156.00 ng/g,甲基汞含量为11.05~155.60 ng/g,甲基汞含量所占总汞含量的比例平均为83.39%。两渔村海水鱼汞含量均未超国标(GB 2762-2017)限量,而甲基汞在海水鱼肌肉中含量占总汞含量的比例平均值为76.45%,即甲基汞是汞在海水鱼肌肉中的主要赋存形态,海水鱼汞形态分布情况可能存在地域差异和品种差异。     

Mercury and Fatty Acids in Canned Tuna, Salmon, and Mackerel

ABSTRACT: Canned tuna ( n = 240), salmon ( n = 16), and mackerel ( n = 16) were analyzed for mercury and fatty acids. Average mercury levels were 188, 45, and 55 ppb, respectively, and below the FDA Action Level of 1000 ppb. "Light tuna in water" contained lower mercury (x = 54 ppb) compared with "white/albacore tuna in water," which contained higher eicosapentaenoic acid/docosahexaenoic acid (EPA/DHA) x= 711 mg/100 g wet tissue). Mercury residues in salmon (x = 45 ppb) and mackerel (x = 55 ppb) were lower than in tuna products, but the EPA/DHA levels were higher (salmon, ×= 1623 mg/100 g wet tissue; mackerel, ×= 851 mg/100 g wet tissue). Information from this study will help women of childbearing age to limit their intake of mercury while obtaining healthy fats from fish.     

淡水鱼中汞含量的分析测定

以上海地区出产的食用淡水鱼为试样,通过冷原子吸收光度法检测鱼体中的汞含量。实验结果表明,同一条鱼中不同部位的鱼肉汞含量基本相同,但鱼肝中的汞含量大于鱼肉中的汞含量,鱼籽中的汞含量小于鱼肉中的汞含量。经分析测定目前上海市区的淡水鱼中总汞含量远低于国家规定的食品中水产品汞的限量标准,最低残留量≤0.3mg/kg。     

Effect of thermal processing and canning on cadmium and lead levels in California market squid: the role of metallothioneins

The effects of two common seafood preparation practices (roasting and industrial canning) on the heavy metal content – cadmium (Cd) and lead (Pb) – of various tissues of California market squid were studied. Emphasis was placed on the role of metallothioneins (MT) in Cd and Pb behaviour during processing. Cd and Pb analysis was conducted by a Zeeman GTA-AAS atomic absorption spectrometry system; MT analysis was performed by a mercury saturation assay. Results showed that Cd levels in the mantle and whole squid were considerably affected by both processing practices, reaching a 240% increase in mantle and a 40% increase in whole squid. Interestingly, Cd behaviour was associated with MT changes during squid processing. On the other hand, Pb content was not affected from either processing or associated with MT content in the raw or processed squid. Therefore, processing operations may affect Cd and Pb content differently due to the specific metal bioaccumulation and chemical features of each heavy metal type.     

Mercury exposure may suppress baseline corticosterone levels in juvenile birds

Mercury exposure has been associated with a wide variety of negative reproductive responses in birds, however few studies have examined the potential for chick impairment via the hypothalamic-pituitary-adrenal (HPA) axis. The HPA axis regulates corticosterone levels during periods of stress. We examined the relationship between baseline fecal corticosterone metabolite concentrations and mercury concentrations in down feathers of recently hatched (<3 days) and blood of older (15-37 days) Forster's tern (Sterna forsteri) chicks in San Francisco Bay, California. Baseline fecal corticosterone metabolite concentrations were negatively correlated with mercury concentrations in blood of older chicks (decreasing by 81% across the range of observed mercury concentrations) while accounting for positive correlations between corticosterone concentrations and number of fledgling chicks within the colony and chick age. In recently hatched chicks, baseline fecal corticosterone metabolite concentrations were weakly negatively correlated with mercury concentrations in down feathers (decreasing by 45% across the range of observed mercury concentrations) while accounting for stronger positive correlations between corticosterone concentrations and colony nest abundance and date. These results indicate that chronic mercury exposure may suppress baseline corticosterone concentrations in tern chicks and suggests that a juvenile bird's ability to respond to stress may be reduced via the downregulation of the HPA axis.