硒和维生素E对大鼠心肌氧化损伤的保护作用

Protective effect of selenium and vitamin E on rat myocardial oxidative injury

目的观察硒和维生素E（VitE）对大鼠血清心肌酶和抗氧化能力的保护作用。方法雄性Wistar大鼠80只，体质量70～90g。按体质量和2X2析因设计将大鼠分为4组：低硒低VitE组（饲料中含低硒酵母23．42％。不含VitE）；低硒常VitE组（饲料中含低硒酵母23．42％、VitE160mg／kg）；常硒低VitE组（饲料中含低硒酵母46．84％，水中含亚硒酸钠0．25mg／L，不含VitE）；常硒常VitE组（饲料中含低硒酵母46．84％、VitE160mg／kg，水中含亚硒酸钠0．25mg／L），每组20只。大鼠饲用合成饲料，在喂养26周后腹腔麻醉，采集大鼠静脉血，制备血清，观察硒和VitE对大鼠心肌酶和心肌抗氧化能力的影响及二者的交互作用。血清肌酸激酶（CK）测定采用连续监测法，肌酸激酶同工酶（CK—MB）和乳酸脱氢酶（LDH）测定采用免疫抑制法，全血谷胱甘肽过氧化物酶（GSH—Px）测定采用二硫代二硝基苯甲酸（DTNB）法，血清超氧化物歧化酶（SOD）测定采用黄嘌呤氧化酶法，总抗氧化能力（T—AOC）测定采用络合物比色法，丙二醛（MDA）测定采用硫代巴比妥酸比色法，活性氧（ROS）测定采用比色法。结果大鼠血清CK、CK—MB、LDH和全血GSH—Px活力，血清T—AOC活力及MDA、ROS含量组间比较差异有统计学意义（F值分别为9．797、17．041、48．399，3．744、224．900、49．384、5．045，P均〈0．05）。CK、CK—MB、LDH活力与常硒常VitE组[（1056．80±250．98）、（721．70±129．98）、（404．65±72．49）U／L）]比较，2个低硒组[（1577．75±451．87）、（1239．15±344．99）、（884．25±133．84）U／L，（1474．21±398．38）、（1014．84±215．40）、（523．00±98．05）U／L]和常硒低VitE组[（1180．10±245．51）、（948．75±173．68）、（676．70±193．63）U／L]明显升高（P均〈0．05）；MDA含量，与常硒常VitE组[（3．010±1．270）×10^3nmol／L]比较，2个低硒组[（5．688±1．169）×10^3、（4．035±0．487）×10^3nmol／L]明显升高（P均〈0．05）；GSH—Px活力，与2个常硒组[（96．611±8．238）×10^3、（103．024±8．217）×10^3U／L]比较，2个低硒组[（60．356±8．179）×10^3，（63．117±8．281）×10^3U／L1明显降低（P均〈0．05）。硒因素对CK、CK—MB和LDH活力有影响作用（F值分别为27．09、31．58、29．66．P均〈0．01），VitE因素对CK—MB和LDH活力有影响作用（F值分别为18．9、11．2，P均〈0．01），但二者对CK、CK—MB和LDH无交互作用（F值分别为0．02、0．00、2．22，P均〉0．05）。硒因素对GSH—Px活力和MDA含量有影响作用（F值分别为6．74、95．68，P均〈0．05），VitE因素对T—AOC活力，MDA和ROS含量有影响作用（F值分别为6．42、36．73、8．43，P均〈0．05），但二者仅对MDA有交互作用（F值为13．82，P〈0．05）。结论长期硒或VitE缺乏，可以使机体的抗氧化能力降低，导致心肌损伤的发生，硒和VitE可提高机体的抗氧化能力，起到保护心肌的作用。

Objective To observe protective effects on rat serum cardiac enzymes and the antioxidant capacity of selenium and vitamin E. Methods According to body weight and 2 × 2 factorial design, eighty male Wistar rats were randomly divided into four groups： low selenium and low vitamin E group（feed containing 23.42% of the low selenium yeast, excluding vitamin E）, low selenium and adequate vitamin E group （feed containing 23.42% of the low selenium yeast and vitamin E 160 mg/kg）, adequate selenium and low vitamin E group （feed containing 46.84% of the low selenium yeast and sodium seleni 0.25 mg/L in water, excluding vitamin E）, adequate selenium and adequate vitamin E group（feed containing 46.84% of the low selenium yeast, vitamin E 160 mg/kg and sodium selenite 0.25 mg/L in water）, 20 rats every group. Rats were feed with synthetic feed, and given intraperitoneal anesthesia after 26 weeks of feeding. Blood was collected to observe the impact of selenium and vitamin E on rat cardiac enzymes and myocardial antioxidant capacity and their interactions. Serum creatine kinase （CK） was measured using the continuous monitoring method, creatine kinase isozymes （CK-MB） and lactate dehydrogenase （LDH） using the immune suppression method, the whole blood GSH-Px assay using the dithiobis nitrobenzoic acid （DTNB） method, serum superoxide dismutase （SOD） using the xanthine oxidase method, total antioxidant capacity（T-AOC） using the complex colorimetry method, the content of propylene glycol （MDA） using the thiobarbituric acid colorimetric method, and reactive oxygen species（ROS） using the colorimetric method. Results Group differences of serum CK, CK-MB, LDH, whole blood GSH-Px activity, serum T-AOC vitality, MDA and ROS content were statistically significant（F = 9.797, 17.041, 48.399, 3.744, 224.900, 49.384, 5.045, all P 〈 0.05）. Compared with the two low selenium groups and one adequate selenium group, the vitalities of CK, CK-MB, LDH and the contents of MDA[ （1577.75 ± 451.87）, （1239.15 ± 344.99）, （884.25 ± 133.84）U/L, （5.688 ± 1.169） ×10^3 nmol/L; （1474.21 ± 398.38）, （1014.84 ± 215.40）, （523.00 ± 98.05）U/L, （4.035 ± 0.487 ）×10^3 nmol/L and （1180.10 ± 245.51）, （948.75 ± 173.68）, （676.70 ± 193.63）U/L, （3.406 ± 0.146）×10^3 nmol/L] increased significantly in adequate selenium and adequate vitamin E group[ （1056.80 ± 250.98）, （721.70 ± 129.98）, （404.65 ± 72.49）U/L, （3.010 ± 1.270）×10^3 nmol/L, all P 〈 0.05）]. The activity of GSH-Px was obviously increased in the two adequate selenium groups [ （96.611 ± 8.238）×10^3, （103.024 ± 8.217）×10^3 U/L, all P 〈 0.05 ], compared with the two low selenium groups[ （60.356 ± 8.179） ×10^3, （63.117 ± 8.281 ）×10^3U/L]. Selenium affected the activities of CK, CK-MB and LDH（F = 27.09, 31.58 , 29.66, all P〈 0.01）, and vitamin E affected the activities of CK-MB and LDH（F= 18.9, 11.2, all P〈 0.01）, but both selenium and vitamin E had no interactions on the activities of CK, CK-MB and LDH （F = 0.02, 0.001, 2.22, all P〉 0.05）. Selenium affected the activity of GSH-Px and the content of MDA（F = 6.74, 95.68, all P〈 0.05）, vitamin E affected the activity of T-AOC, the contents of MDA and ROS（F= 6.42, 36.73, 8.43, allP〈 0.05）, but selenium and vitamin E had interactions only on the content of MDA （F = 13.82, P 〈 0.05）. Conclusions Long-term selenium or vitamin E deficiency, can reduce the body＇ s antioxidant capacity, leading to the occurrence of myocardial injury. Selenium and vitamin E can improve the body＇s oxidation capacity, playing a role in myocardial protection.