Objective To explore the effect of oxygen inhalation on the retinae of newborn rats and its mechanism.Methods We mimicked the retinopathy of prematurity(ROP) by putting the newborn rats in high concentrated oxygen. One-day old rats were put into the oxygen box with the oxygen concentration of 80% for continuous 7 days; then in air condition for 7 days. The arterial blood oxygen pressure, retinal superoxide dismutase (SOD), and malondialdehyde (MDA) of the rats (1,2,4,7,8,9,11,14 days old) were examined. The diameter of retinal vessels′main branch and the coverage rate of peripheral vessels were measured in 7- and 14-day-old rats by ink perfusion. The retinal neovascularization of rats (8,9,11, 14 days old) were observed by HE staining. The rats of the same age fed in air condition were in the control group.Results The differential pressures of blood oxygen of rats (1,2,4,7 days old) in study group were significantly higher than those in the control group (P＜0.01), while the differential pressures of blood oxygen of rats (8,9,11,14 days old) in study group were lower than those in the control group (P＞0.05). The contents of SOD of the retinae in the rats ( 1,2,4,7,8 days old) were significantly lower than those in the control group(P＜0.01, P＜0.05 ), while the contents of MDA were significantly higher than those in the control group (P＜0.01,P＜0.05). The diameter of retinal vessels′main branch in 7-day rats was 75% of the control group, and the coverage rate of peripheral vessels was 22% of the control group; and was 61% and 73% respectively in 14-day-old rats. The neovascularization could be seen in 16.7% of the rats in the study group and nought in the control group.Conclusion The damage of free radical of the retina in high concentrated oxygen and hypoxia situation after oxygen supply may be one of the most important mechanism of ROP. (Chin J Ocul Fundus Dis，2003，19：269-332)
Objective To explore the potential protective effect in vivo of Edaravone, a free radical scavenger on model of acute lung injury in rats with sepsis. Methods Twenty-four male Wistar rats were randomly divided into three groups, ie. a control group( NS group) , a model group( LPS group) , a Edaravone treatment group( ED group) . ALI was induced by injecting LPS intravenously( 10 mg/ kg) in the LPS group and the ED group. Meanwhile the ED group was intravenously injected with Edaravone( 3 mg/ kg) . The NS group was injected with normal saline as control. The lung tissue samples were collected at 6 h after intravenous injection. The wet / dry ( W/D) weight ratio of lung tissue was measured. The levels of myeloperoxidase ( MPO) , malondialdehyde ( MDA ) and superoxide dismutase ( SOD) in lung tissue homogenate were assayed. The pathological changes and expression of nuclear factor-kappa B( NF-κB) in lung tissue were also studied. Results Compared with the NS group, The W/D, pathological scores, NF-κB expression, MPO and MDA levels in the LPS group were significantly higher( all P lt; 0. 01) , and the level of SOD was apparently lower( P lt; 0. 01) . The W/D, pathological scores, NF-κB expression, MPO and MDA levels in the ED group were significantly lower than those in the LPS group( all P lt; 0. 01) and higher than those in the NS group( all P lt; 0. 01) . And the level of SOD in lung tissue of the ED group was higher than that in the LPS group and lower than that in the NS group ( P lt; 0. 01) . Conclusions Edaravone has protective effect on ALI rat model. The mechanismmay be related to its ability of clearing the reactive oxygen species, inhibiting the activation of the signal pathway of NF-κB and inflammatory cascade.
目的:研究大豆异黄酮对D半乳糖致衰老大鼠抗氧化能力的影响。方法:用D半乳糖注射Wistar雄性大鼠5个月,建立衰老模型。对致衰老模型组、大豆异黄酮组肝脏、心脏和前列腺丙二醛(MDA)含量、超氧化物歧化酶(SOD)、谷胱甘肽过氧化酶(GSHPx)活性进行测定及比较。结果:低、中、高不同剂量大豆异黄酮灌喂组与模型组大鼠相比,各脏器MDA含量(μmol/L)(心脏:695±093,562±112,435±112比802±111;肝脏:815±085,647±120,515±112比935±135;前列腺:715±092,558±115,423±125比833±124)均有降低,差异有统计学意义(Plt;005),而SOD酶活性(nmol/L)(心脏:4732±308,5518±428,6120±368比3225±370;肝脏:18121±506,19015±706,19720±570比17213±512;前列腺:4156±301,4607±421,5015±335比3374±305)和GSHPx酶活性(nmol/L)(心脏:905±096,1111±245,1313±146比713±151;肝脏:902±105,1150±223,1362±192比698±160;前列腺:435±085,613±102,747±155比312±106)有升高,差异同样具有统计学意义(Plt;005);大豆异黄酮摄入量越高,MDA含量越低,而SOD、GSHPx酶活性越高。结论:摄入适量大豆异黄酮可有效增强大鼠机体抗氧化能力,从而延缓D半乳糖诱发的大鼠衰老。
目的:探讨甲状腺功能亢进症(甲亢)患者血浆对氧磷酯酶1(PON1)活性变化以及与其它氧化应激指标的关系。方法:分别测定50名对照组和78例甲亢组空腹血浆中游离三碘甲状腺原氨酸(FT3)、游离甲状腺素(FT4)、促甲状腺激素(TSH)、PON1活性、超氧化物歧化酶(SOD)、丙二醛(MAD)、氧化低密度脂蛋白(ox-LDL)及血脂含量,并进行相关性分析。 结果:甲亢患者血浆PON1活性(139 ±64)kU/L,ox-LDL(598.3±58.6)μg/L,MDA(15.11±3.26) μmol/L及SOD(80.2±25.3)NU/mL。对照组上述指标分别为:PON1(168 ±70)kU/L,ox-LDL (446.2±62.2) μg/L,MDA (10.02±3.00) μmol/L,SOD(92.9±26.9)NU/mL。血浆PON1和SOD活性显著低于对照组(Plt;0.01),ox-LDL和MDA水平显著高于对照组(Plt;0.01)。甲亢患者血浆PON1活性与SOD呈正相关(r=0. 381,Plt; 0.05),与ox-LDL、MDA呈负相关(r=-0. 411,r=-0. 445,Plt; 0.01)。 结论:甲亢患者血浆PON1活性显著降低,可能与氧化应激增强有关。
Objective To investigate the effects of ecdysterone on the survival of the dorsal random-pattern skin flap with large length-to-width ratio in rats and its possible mechanisms. Methods Twenty-four healthy adult SD rats (male and/or female) weighing 200-250 g were randomly divided into the experimental group and the control group (n=12 per group).A caudally based dorsal random pattern skin flap, measuring 8 cm × 2 cm, was symmetrically raised. Ecdysterone (5 mg/kg) and normal sal ine (5 mg/kg) were injected into the abdominal cavity of rats in the experimental group and the control group at 10 minutes before operation and from the first to the fifth day after operation, respectively. The general condition of the rats was observed after operation. At 7 days after operation, the survival rate of the flap was detected, the superoxide dismutase (SOD) activity and the malonyldialdehyde (MDA) level were tested, HE and immunohistochemistry staining observation of the flap were performed. VIII factor dried microvessels in the middle part of the flap (4 cm far away from pedicle) were counted. Results All the rats survived until the end of the experiment. At 7 days after operation, the survival rate of the flap was 62.323% ± 7.046% in the experimental group and 47.753% ± 2.952% in the control group (P lt; 0.001); SOD activity was (54.560 ± 4.535) U/mgprot in the experimental group and (23.962 ± 3.985) U/mgprot in the control group (P lt; 0.001); MDA level was (8.445 ± 0.992) nmol/mgprot in the experimental group and (14.983 ± 0.929) nmol/mgprot in the control group (P lt; 0.001). Histology observation: compared with the control group, the inflammatory cells infiltration was less and the hyperplasia of fibers was more obvious in the experimental group. The microvessel counting in the middle part of the flap was 17.817 ± 2.420 in the experimental group and 8.967 ± 2.000 in the control group (P lt; 0.001). Conclusion Perioperative intraperitoneal injection of ecdysterone can promote the survival of the random-pattern skin flaps with large length-to-width ratio. Its mechanism may be related to its effects of improving SOD activity, decreasing l ipid peroxidation, and promoting angiogenesis of skin flaps.
目的:研究缺氧预处理对老年大鼠子宫及双附件切除术后疲劳是否有改善作用,并通过对比观察超氧化物歧化酶及丙二醛水平的变化,初步探讨缺氧预处理的作用机制。方法:将老年大鼠分为空白对照组、对照组、缺氧预处理三组。空白对照组为假手术组,对照组为子宫及双附件切除术组, 缺氧预处理组为缺氧预处理加子宫及双附件切除术组。对比观察缺氧预处理对大鼠体力活动及血清超氧化物歧化酶和丙二醛水平的影响。结果:空白对照组、对照组、缺氧预处理三组大鼠悬尾不动时间分别为:(21±3)s,(83±10)s,(44±5)s,各组间比较Plt;0.05。三组SOD活性分别为:(131.23±5.31)U/L,(36.12±9.68)U/L,(73.01±9.82)U/L,各组间比较Plt;0.05。三组MDA水平分别为:(9.78±1.26)μmol/L,(29.87±3.13)μmol/L,(15.98±2.21)μmol/L,各组间比较Plt;0.05。结论:缺氧预处理可提高老年大鼠的抗氧化能力,对老年大鼠子宫及双附件切除术后疲劳综合征有明显的改善作用。
To study the variations of l ipid peroxidation products and copper, zinc-superoxide dismutase(CuZn-SOD) in pathological scars (hypertrophic scars and keloids). Methods The specimens were gained from patients of voluntary contributions from May 2005 to August 2005. The tissues of hypertrophic scar (10 cases, aged 16-35 years, the mean course of disease was 2.2 years), keloid (10 cases, aged 17-32 years, the mean course of disease was 8 months) and normal skin (8 cases, aged 16-34 years) were obtained. The content of malonaldehyde (MDA)and CuZn-SOD activity were detected by spectrophotometric method. The expression of CuZn-SOD was evaluated by immunohistochemistry technique. Results The contents of MDA and CuZn-SOD activity were significantly higher in hypertrophic scars[MDA (1.139 0 ± 0.106 7)nmoL/mg prot, CuZn-SOD (31.65 ± 2.21)U/mg prot, (P lt; 0.05)]and keloids[MDA (1.190 0 ± 0.074 8)nmoL/ mg prot, CuZn-SOD (34.36 ± 5.01)U/mg prot (P lt; 0.05)] than those of normal skin tissues [MDA (0.821 3 ± 0.086 4)nmoL/mg prot, CuZn-SOD (20.60 ± 5.56)U/mg prot]. Immunohistochemical studies indicated that the brown particles were CuZn-SOD positive signals, which mainly located cytoplasm in normal skin tissues, hypertrophic scars as well as keloids epidermal keratinocytes and dermal fibroblasts. CuZn-SOD expression evaluation in hypertrophic scars (4.14 ± 0.90, P lt; 0.05) and keloids epidermal keratinocytes (4.43 ± 0.79, P lt; 0.05) markedly increased when compared with normal skin tissues (2.20 ± 0.45). The expression of CuZn-SODin hypertrophic scars (4.00 ± 0.82, P lt; 0.05) and keloids dermal fibroblasts (4.43 ± 0.53, P lt; 0.05) were significantly higher than that of normal skin tissues (1.60 ± 0.89). There were no differences in the content of MDA, CuZn-SOD activity and expression evaluation between hypertrophic scars and keloids (P gt; 0.05). Conclusion In pathological scars, the contents of MDA and CuZn-SOD activity increase and the expressions of CuZn-SOD are enlarged.
Perfusion of free flaps from groin of rabbits, after 12 hours of complete ischemia, with superoxide dismutase (SOD), an oxygen free radical scavenger, would significantly increase the survival rate of these flaps from 18.75% to 75% in the control group. Tissue levels of SOD and malonydialdehyde (MDA, an end product of lipoperoxidation) were measured before ischemia, after ischemia but before reperfusion, and 60 minites after reperfusion. In untreated flap, after 12 hours- ischemia, the SOD content of skin decreased significantly as compared with the SOD content before ischemia, and reperfusion further decreased SOD activity, while the concentration of MDA increased after ischemia and further increased after reperfusion. In the treated flaps, the concentration of SOD was not decrease and MADnot increased after reperfusion. There was a negative correlation between the values of SOD and MDA. These findings suggested that free oxygen radicals playedan important role in the free flap ischemia reperfusion injury. SOD could increase the survival of ischemic free-flaps by reducing lipoperoxidation. The results had significant clinical implications with regard to organ preservation and transplantation.