Liver SOD Activity Research Articles

Effect of postconditioning with propofol and ischemia on hepatic ischemia-reperfusion injury in rats

Objective To investigate the effect of postconditioning with propofol and ischemia on the hepatic ischemia-reperfusion (I/R) injury in rats. Methods Thirty male SD rats weighing 200-250 g were randomly divided into 5 groups of 6 animals each: group I sham operation (group S); groupⅡ I/R; group Ⅲ ischemic postconditioning (group IPC); group Ⅳ propofol postconditioning (group PPC) and group V IPC + PPC. In group Ⅱ-Ⅳ the hepatic arteries and veins of middle and left lobes were occluded for 1 h followed by 4 h reperfusion. Ischemia of the liver was confirmed by the color of the liver turning from red to gray. In group Ⅲ and Ⅴ the livers were subjected to six episodes of 10 s ischemia at 10 s intervals at the end of 1 h ischemia before 4 h reperfusion. In group Ⅳ and V 0.5 % propofol 10 mg/kg was given iv at the end of ischemia followed by propofol infusion at 40 mg·g~(-1) ·h~(-1). Blood samples were taken at the end of 4 h reperfusion for determination of serum ALT activity. Mean-while liver specimens were taken for electron microscopic examination and determination of MDA content and SOD activity. Results I/R significantly increased serum ALT activity and MDA content in the liver and decreased liver SOD activity in group Ⅱ . The I/R-induced changes were significantly attenuated by propofol and/or ischemic postconditioning in group Ⅲ ,Ⅱ and Ⅴ . I/R significantly increased Bel-2 and Bax protein expression in the liver cells. Propofol and/or ischemic postconditioning increased Bel-2 protein expression further but decreased Bax protein expression in group Ⅲ , Ⅳ and Ⅴ as compared with group Ⅱ (group I/R).Electron microscopic examination showed that the pathologic changes induced by I/R were less severe in group Ⅲ, Ⅳ and Ⅴ than in group I/R. Conclusion Postconditioning with propofol and ischemia can reduce the hepatic I/R injury and the mechanism may be related to inhibition of lipid peroxidation and apoptosis, but the efficacy is the same as that of propofol postconditioning alone. Key words: Propofol; Reperfusion injury; Hepatic; Ischemic postconditioning

The influence of vitamin E supplementation on the oxidative status of rat liver

We tested to see if the additional intake of vitamin E in the form of ?-tocopheryl-succinate would improve liver antioxidative protection. Thus, we studied the tissue oxidative status in rats supplemented by two doses of the antioxidant over a four week period of time. Our results confirmed that the additional intake of vitamin E decreased the liver lipid peroxidation level and SOD activity level and preserved its vitamin C content. However, the hydrogen peroxide content and catalase activity remained unchanged, probably due to the mechanism of vitamin E liver metabolism. .

GABA 생성능 우수 김치 젖산균 Lactobacillus sp. OPK2-59의 간 기능 개선 효과

This study investigated the effect of improved liver function in rats administered with ethanol by kimchi lactic acid bacteria with high GABA producing capacity. Sprague-Dawley male rats were divided into four groups; normal diet control (NC), ethanol control (EC), ethanol＋Lactobacillus sp. OPK2-59 normal powder (EL1), ethanol＋Lactobacillus sp. OPK2-59 GABA powder (EL2) and fed for 6 weeks. Analysis showed that there were no significant differences in body weight and feed consumption among the groups during the experimental period. Also, there were no significant differences in organ weight among the groups. The test results showed total cholesterol and triglyceride in the blood concentration that were increased by ethanol administration were significantly lowered in EL2 group. Liver triglyceride was also significantly lowered in the EL2 group compared with the EC group. Serum GOT and GPT, and liver GOT levels were significantly lower in the EL2 group compared with the EC group. Serum ethanol concentration was lower in the EL1 and EL2 groups compared with the EC group. SOD activities in liver were significantly increased in the EL1 and EL2 groups compared with the EC group. These results suggest that Lactobacillus sp. OPK2-59 GABA powder improves lipid and enzyme profiles of rats administered with ethanol.

Hypoglycemic and hypolipidemic effect and antioxidant activity of chronic epigallocatechin-gallate in streptozotocin-diabetic rats

Background and objective: Green tea catechins including epigallocatechin-3-gallate (EGCG) could exert beneficial health effects to ameliorate metabolic diseases. The effect of chronic administration of EGCG was evaluated on serum glucose and lipid profile and hepatic lipid peroxidation in streptozotocin (STZ)-diabetic rats. Materials and methods: Rats received EGCG 25 mg/kg/day for 8 weeks 1 week after diabetes induction. Serum glucose, triglyceride, total cholesterol, HDL- and LDL-cholesterol levels and MDA level and SOD activity in hepatic tissue were spectrophotometrically measured. Results: Treatment of diabetic rats with EGCG produced a hypoglycemic effect and there were appropriate changes regarding serum lipids in treated diabetic group. Meanwhile, EGCG treatment attenuated the increased MDA content and reduced activity of SOD in liver. Conclusion: Chronic treatment of diabetic rats with EGCG could prevent abnormal changes in blood glucose and lipid profile and attenuat hepatic lipid peroxidation.

고콜레스테롤 식이 섭취 흰쥐에 대한 적송잎 추출물의 항산화 효과

This study was conducted to investigate the effects of pine (Pinus densiflora) needle extracts on hepatic antioxidative system in rats fed high-cholesterol diet. Eight-week old Sprague Dawley rats were divided into four groups; normal diet group (CON), 0.5% cholesterol diet group (0.5% CHOL), 0.5% cholesterol diet and pine needle extracts prepared by using hot water group (HOT water), and 0.5% cholesterol diet and pine needle extracts prepared by using sub-supercritical CO₂ group (Sub-supercritical). The serum ALP, AST, and ALT activities were increased by 0.5% cholesterol diet supplementation, but treatment with pine needle extracts showed decrease compared with 0.5% CHOL group. The SOD activity in liver at 0.5% cholesterol diet group was more decreased than control group while Sub-supercritical group had significantly higher SOD activity than 0.5% CHOL group. Moreover, groups with pine needle extracts supplementation had higher level of GPx in liver than 0.5% cholesterol diet group. These results suggest that pine needle extracts increased antioxidative activities.

Effects of dietary calcium and milk on oxidative and inflammatory stress and lifespan in wild‐type and aP2‐agouti transgenic mice

Dietary Ca reduces oxidative and inflammatory stress, while milk exerts a greater effect than supplemental Ca. To examine the effects on lifespan and related biomarkers, aP2‐agouti transgenic mice (model of diet‐induced obesity) and wild‐type littermates were fed a low Ca (0.4% Ca), high‐Ca (1.2% Ca from CaCO3), or milk (1.2% Ca from non‐fat dry milk) obesigenic diets until death. Randomized subgroups were sacrificed at 28, 52 and 78 weeks of age for biomarker analysis. The milk diet attenuated weight and adiposity gain and prevented the age‐related muscle loss (p<0.04) and rise in reactive oxygen production (ROS) in adipose tissue (p=0.005). There was a corresponding increase in SOD3 (in wild‐type, p=0.04) and glutathione peroxidase gene expression (p<0.02) in soleus, and in liver SOD activity (p<0.04). The milk diet decreased adipose tissue IL6 (p<0.05) and TNFα (p<0.03) expression in male mice only. The survival analysis showed an overall shorter lifespan in transgenic vs. wild‐type mice. Although no diet effect was found on lifespan, the milk diet resulted in a significant increase in early (75%) survival rate in wild‐type mice (p<0.02). These data demonstrate that milk diet attenuates adiposity, protects against muscle loss and reduces oxidative and inflammatory stress. Although these effects did not influence maximum lifespan, they did suppress early mortality.Grant Funding SourceThe National Dairy Council

Study on Hypoglycemic Function of Polysaccharides from Lycium ruthenicum Murr. Fruit and Its Mechanism

In this study, two ways was used to prove and explain the hypoglycemic function of polysaccharides from Lycium ruthenicum Murr. fruit, among which, one way was to preventively administer the normal mice by gavage with the low, middle or high dosages of the polysaccharides for 11 d, and then intraperitoneally inject the prevented mice with alloxan, and another way was to intraperitoneally inject the normal mice with alloxan to establish diabetic models, and then intraperitoneally administer the diabetic mice by gavage with the low, middle or high dosages of the polysaecharides for 21 d. Finally the hepatin in liver, SOD activity and MDA content in serum and liver, and fasting blood glucose level were determined for the control group, diabetic model group, all treatment groups and metformin hydrochloride group. The results showed that the polysaccharides signifi- cantly can reduce glucose level in blood and MDA content in blood and liver, and enhance SOD activity in blood and liver and promote conversion of blood glucose into liver glycogen of diabetic mice. In conclusion, the polysaccharides from Lycium ruthenicum Murr. fruit has prevention and therapeutic effects on hyperglycemia, and can effectively enhance the anti-oxidation ability in diabetic mice induced by alloxan.

Inhibition of mitomycin C-induced chromosomal aberrations by micrometer powder of selenium-enriched green tea in mice spermatocytes

The anticlastogenic effect of micrometer powder of selenium-enriched green tea (MSTP) was evaluated by using a chromosomal aberration assay in mouse testicular cells. Animals fed with a Se-deficient diet were treated with MSTP, micrometer powder of regular green tea (MRTP), selenite, and MRTP + selenite for 30 days by an intragastric route, followed by treatment of mitomycin C (MMC) on day 19 through intraperitoneal injection (ip). Selenium status and antioxidant enzymes were measured. Results indicated that MSTP showed a significant capability to reduce the incidence of MMC-induced chromosomal aberrations in spermatocytes from 22.7% to 6.7%. This inhibitory was highest, for MSTP, at 73.1%, while it was only 38.4% for MRTP. After 30 days of a Se-deficient diet, mice, either with or without the MMC treatment, showed a lower selenium concentration in blood and liver as well as lower enzyme activity of the antioxidants, GPx and SOD. Supplementation with MSTP, selenite, or selenite + MRTP enhanced the activities of these antioxidant enzymes. This enhancement was accompanied with a concomitant elevation of selenium levels, which favored the synthesis of the seleno-enzyme GPx and protected the cells from the MMC-induced oxidative stress. Our results indicate that MSTP is both able to prevent the chromosomal aberrations induced by MMC in mouse spermatocytes and to enhance GPx and SOD activity in blood serum and liver.

Effect of different level and source of copper supplementation on immune response and copper dependent enzyme activity in lambs

An experiment was conducted on 30 male Nellore lambs with average body weight (BW) of 15.45 +/- 0.06 kg to determine the level of the copper (Cu) supplementation in diet from inorganic and organic sources required for optimum immunity and its effect on copper dependent enzymes by allotting them randomly to five groups in completely randomized design. The dietary treatments were viz., basal diet (no Cu supplementation, BD), other four groups were offered BD supplemented with 7 or 14 ppm Cu from copper sulphate (CuSO(4)) and Cu-proteinate, respectively. The lambs were fed the respective diets at 3.5 per cent BW to meet the requirements except Cu for 180 days. The humoral immune response against Brucella abortus and chicken RBC was assessed after 90 days of feeding. The in vivo delayed type hyper sensitivity reaction against PHA-P and in vitro lymphocyte proliferation against Con A indicative of cell mediated immune response (CMI) was assayed at 180 days of feeding. At the end of experiment four lambs from each group were slaughtered for estimation of liver superoxide dismutase activity (SOD). The ceruloplasmin and RBC-SOD activities were higher (P < 0.05) in 14 ppm Cu supplemented lambs from Cu-proteinate at 90 and 180 days, while the liver SOD activity was higher (P < 0.05) in lambs fed 14 ppm Cu from CuSO(4). The STAT titres against B. abortus were higher in Cu supplemented lambs, with no effect of dose of supplementation. Lambs supplemented with Cu-proteinate had higher titers than CuSO(4) on 7 and 14 days of post sensitization. The total immunoglobulin concentration and the CMI response against PHA-P and Con-A was higher (P < 0.05) in lambs fed 14 ppm Cu-proteinae diet. The IgM level was though high in Cu supplemented lambs, no dose or source effect were observed. The study indicated that Cu dependent enzymes activity and immune response were highest and respond better against stress in lambs on 14 ppm supplemented Cu from Cu-proteinate.

Antidiabetic and antioxidant effect of Panax ginseng

The present study was conducted to investigate the biochemical and immunomodulatory effects of Panax ginseng (Araliaceae) roots on diabetic, obese and obese diabetic rats. In this regard, 120 rats were divided into eight groups; control, normal treated, diabetic, treated diabetic, obese, treated obese, obese diabetic and treated obese diabetic groups. Blood glucose, serum IL-6 and TNF-α level showed highly significant increase (P&lt;0.005) in diabetic, obese and obese-diabetic groups (non-treated groups) as compared with the control group. These values showed highly significant decrease after treatment (22.5mg/kg b.w. orally/day) with Ginseng extract (P&lt;0.005). Plasma insulin level showed highly significant increases (P&lt;0.005) in both obese and obese-diabetic groups while in the diabetic group it showed a highly significant decrease (P&lt;0.005) as compared with the control group. On the contrary, both of the treated obese and treated obese-diabetic groups showed significant decreases in plasma insulin level, (P&lt;0.05) while the treated diabetic group showed a highly significant increase (P&lt;0.005) as compared with non-treated groups. Serum triglyceride-Total cholesterol -LDL-cholesterol level increased highly significantly (P&lt;0.005) in non-treated groups as compared with the control group while it decreased highly significantly in treated groups as compared with non-treated groups, but HDL-cholesterol level showed highly significant decreases in non-treated groups as compared with the control groups and showed highly significant increases (P&lt;0.005) in the treated groups toward normal value as compared with non-treated groups. GST, GSH, SOD and GSH-PX activity in both liver and kidney tissue showed significant decreases (P&lt;0.05) in non-treated groups as compared with the control group. These results showed significant increases in both of treated diabetic and treated obese-diabetic groups and a non-significant increase in the treated obese group as compared with non-treated groups. MDA (malondialdehyde) levels showed highly significant increase (P&lt;0.005) in the diabetic and obese diabetic groups. After treatment with ginseng significant decreases in MDA levels were observed. In conclusion, Panax ginseng has antidiabetic and antioxidant properties

Can enzymatic antioxidant defences in liver discriminate between wild and sea cage-reared Bluefin Tuna quality?

Bluefin Tuna ( Thunnus thynnus L.) is a fish species of high nutritional and commercial value that is increasingly farmed in the Mediterranean basin. Oxidative stress research in aquaculture is particularly important in the assessment of both the health of farmed fish and seafood quality. Reactive oxygen species (ROS) are able to start the lipid peroxidation process which is potentially dangerous in fish, since they contain a high percentage of n-3 polyunsaturated fatty acids, in particular C20:5 n-3 and C22:6 n-3, which account for most of seafood's nutritional quality. The study of the antioxidant system and how the various components interact to delay post-harvest lipid peroxidation covers both the improvement of quality and the extension of shelf life of the fresh tuna product. In this study, hepatic antioxidant enzymes (catalase—CAT, superoxide dismutase—SOD and glutathione peroxidase—GPx) and lipid peroxidation levels (TBARS) of wild and sea cage-reared tunas were investigated. The aim was to examine the possible oxidative stress state of wild tunas killed by different fishing methods, compared with reared specimens exposed to different periods of confinement but killed by the same method. No significant differences between wild specimens were found in relation to catching techniques. A significant depletion was observed in liver SOD activity in reared tunas (5.00 U/mg protein) in comparison with wild specimens (5.90 U/mg protein). No differences in liver CAT activity between wild and reared tunas were found. In reared specimens we observed an oxidative stress state indicated by an increase in GPx activity (104.70 U/mg protein and 0.83 U/mg protein in reared and wild tunas, respectively). A significantly higher liver lipid content was observed in reared tunas, but no significant differences between wild and reared tunas in terms of TBA reactive substances content were found (2.03 vs 2.02 micromol TBARS/mg lipid). Our results suggest that the increased GPx activity leads to the suppression of lipid peroxidation in liver of reared tunas. This is the first time that antioxidant enzyme activities have been assayed in Bluefin Tuna and the stress state seems to be related to the diet of reared specimens rather than to their confinement, as indicated by the absence of differences in the antioxidant activities related to the period of confinement.

Hepatoprotective effects of Ganoderma lucidum peptides against d-galactosamine-induced liver injury in mice

Ganoderma lucidum (GL), a traditional Chinese medicinal mushroom, has been widely used for the treatment of chronic hepatopathy of various etiologies. The hepatoprotective activity of peptides from Ganoderma lucidum (GLP) was evaluated against d-galactosamine ( d-GalN)-induced hepatic injury in mice. GLP was administered via gavage daily for 2 weeks at doses of 60, 120 and 180 mg/kg, respectively. Control groups were given the same amount of physiological saline synchronously. Then the mice from d-GalN control and GLP-treated groups were treated with d-GalN (750 mg/kg) suspended in normal saline by intraperitoneal injection. d-GalN-induced hepatic damage was manifested by a significant increase in the activities of marker enzymes (AST, ALT) in serum and MDA level in liver ( P < 0.01), and by a significant decrease in activity of SOD and GSH level in liver ( P < 0.01). Pretreatment of mice with GLP reversed these altered parameters to normal values. The biochemical results were supplemented by histopathological examination of liver sections. The best hepatoprotective effects of GLP were observed after treatment with the dose of 180 mg/kg as it was evidenced from biochemical parameters and liver histopathological characters which were similar to those of normal control group. Results of this study revealed that GLP could afford a significant protection in the alleviation of d-GalN-induced hepatocellular injury.

The effect of potassium dichromate on free radical processes in goldfish: Possible protective role of glutathione

The effects of 96 h exposure to Cr 6+ (added as potassium dichromate) on the status of antioxidant defenses and markers of oxidative damage were evaluated in three tissues of goldfish, Carassius auratus. Fish exposure to high dichromate concentrations, 10 and 50 mg/l, increased protein carbonyl levels in brain and liver, but not in kidney. Chromium exposure also increased concentrations of lipid peroxides in brain (at 5 mg/l) and liver (10 mg/l), but not in kidney. The concentrations of reduced glutathione (GSH) were higher in the liver of goldfish treated with 5–50 mg/l Cr 6+ than in controls, but in kidney only the 5 mg/l-treated group showed increased GSH levels. Dichromate at 1 mg/l increased the concentration of oxidized glutathione (GSSG) in liver and kidney by 80% and 60%, respectively, whereas at 10 and 50 mg/l the levels of GSSG decreased by 50% in kidney. These results indicate that the dichromate concentrations used induced oxidation of lipids and proteins in goldfish tissues in a concentration- and tissue-specific manner. Also, the redox status of fish tissues was affected in a concentration- and tissue-specific manner. The activities of glutathione reductase increased in all three tissues in response to dichromate treatment, increasing by ∼2-fold in brain and liver in goldfish treated with 50 mg/l Cr 6+. Dichromate treatment did not change the activities of SOD, catalase or GST in brain, but reduced the activities of SOD in liver and kidney, and catalase in liver. The results suggest that the glutathione system may be responsible for protecting against the deleterious effects of dichromate in fish and indicate the possible development of an adaptive response during the 96 h treatment with the toxicant.

Antidiabetic and In Vivo Antioxidant Activity of Ethanolic Extract of Bacopa monnieri Linn. Aerial Parts: A Possible Mechanism of Action

Diabetes mellitus is a metabolic disorder affecting carbohydrate, fat and protein metabolism that affects nearly 10% of the population every year. The treatment of diabetes mellitus has been confined to use of oral hypoglycemic agents and insulin, the former being reported to possess serious side effects. This leads to increasing demand for herbal products with antidiabetic factor with little side effects. This article describes the antihyperglycaemic activity, in vivo antioxidant potential, effect on glycosylation of hemoglobin and in-vitro peripheral utilisation of glucose of the ethanolic extract of the aerial parts of Bacopa monnieri. The extract produced significant decrease in the blood glucose level when compared with the controls in alloxan induced hyperglycemic rats both in the single dose as well as multiple dose experiment at the tested dose level and is comparable with the standard drug glibenclamide. It was observed that the ethanolic extract reversed the weight loss of the diabetic rats and they returned to near normal. The extract prevented significant elevation of glycosylated hemoglobin in vitro, with IC 50 value being 11.25 µg/ml that is comparable with the reference drug α-tocopherol. Administration of the exract and glibenclamide significantly decreased the levels of TBARS, increased the content of GSH and increased the activity of SOD and CAT in liver of diabetic rats. The extract increased peripheral glucose utilisation in the diaphragm of diabetic rats in vitro, which is comparable with the action of insulin. Thus, the extract might have insulin like activity and the antihyperglycemic effect of the extract might be due to an increase in peripheral glucose consumption as well as protection against oxidative damage in alloxanised diabetes.

Hypocholesterolemic Effects of Phenolic Extracts and Purified Hydroxytyrosol Recovered from Olive Mill Wastewater in Rats Fed a Cholesterol-Rich Diet

In our previous studies, a phenolic-rich extract of olive mill wastewaters (OMW) was prepared under optimal conditions, using a continuous countercurrent extraction unit, and hydroxytyrosol was purified from the obtained OMW extract. The antioxidant activity of OMW extract and hydroxytyrosol was determined by a series of models in vitro. In this study, the hypocholesterolemic effects of hydroxytyrosol and OMW extract in rats fed a cholesterol-rich diet were tested. Wistar rats, fed a standard laboratory diet or a cholesterol-rich diet for 16 weeks, were used. Serum lipid levels, as well as thiobarbituric acid reactive substances (TBARS) and superoxide dismutase and catalase activities in liver were examined. Cholesterol-rich diet-induced hypercholesterolemia was manifested in the elevation of serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C). Administration of a low-dose (2.5 mg/kg of body weight) of hydroxytyrosol and a high-dose (10 mg/kg of body weight) of OMW extract significantly lowered the serum levels of TC and LDL-C while increasing the serum levels of high-density lipoprotein cholesterol (HDL-C). Furthermore, the TBARS contents in liver, heart, kidney, and aorta decreased significantly after oral administration of hydroxytyrosol and OMW extract as compared with those of rats fed a cholesterol-rich diet. In addition, OMW phenolics increased CAT and SOD activities in liver. These results suggested that the hypocholesterolemic effect of hydroxytyrosol and OMW extract might be due to their abilities to lower serum TC and LDL-C levels as well as slowing the lipid peroxidation process and enhancing antioxidant enzyme activity.

Genistein과 Daidzein 급여가 제2형 당뇨동물모델의 적혈구와 조직 중의 항산화방어계에 미치는 영향

제2형 당뇨 동물모델(C57BL/KsJ-db/db)을 대상으로 대두 이소플라본의 주성분인 genistein과 daidzein의 항산화효능을 검증하고자 5주령의 수컷 C57BL/KsJ-db/db 마우스와 그의 이형접합체인 C57BL/KsJ-db/+ 마우스를 2주간 환경에 적응시킨 후 비당뇨군(db/+), 당뇨대조군(db/db), genistein 급여군(db/db-genistein), daidzein 급여군(db/dbdaidzein)으로 나누어 6주간 사육하였다. 실험동물의 간, 부고환지방과 신주변지방의 조직무게는 당뇨군(db/db)이 비당뇨군(db/+)에 비해 유의적으로 높았으나, 심장무게는 유의적으로 낮았다. Genistein과 daidzein 급여는 장기무게 변화에 영향을 미치지 않았다. 적혈구의 SOD와 CAT활성은 혈당과 양의 상관성을 보였으나 GSH-Px활성은 음의 상관성을 나타내었다. 따라서 SOD와 CAT활성은 db/db군이 db/+군에 비해 유의적으로 높은 반면, GSH-Px 활성은 유의적으로 낮았다. Genistein과 daidzein 급여로 db/db군의 증가된 CAT활성은 감소되었으며 GSH-Px활성은 높게 나타났다. 적혈구의 GSH함량은 당뇨군들이 비당뇨군에 비해 유의적으로 높았으나 genistein과 daidzein에 의한 영향은 관찰되지 않았다. 간, 신장 및 심장조직 내 SOD활성은 유의적인 변화가 없었으나 간조직 중 CAT와 GSH-Px활성과 신장조직 중의 GSH-Px활성은 db/db군이 db/+군에 비하여 유의적으로 높게 나타난 반면 신장조직 중의 CAT활성과 심장조직 중의 CAT와 GSH-Px활성은 낮았다. 그러나 genistein과 daidzein 급여는 고혈당으로 인한 조직 내 CAT와 GSH- Px활성을 유의적으로 개선하였다. 적혈구를 비롯하여 모든 조직 내 지질과산화물 함량은 db/db군이 db/+군에 비하여 유의적으로 높았으나 genistein과 daidzein 급여로 간, 신장과 심장조직 중의 지질과산화물 생성이 유의적으로 억제되었다. 이와 같이 genistein과 daidzein은 제2형 당뇨동물에서 고혈당으로 야기되는 적혈구와 조직 내 항산화효소 변화를 완화하고 간, 신장 및 심장조직의 지질과산화물을 낮추는 것으로 관찰됨으로써 이들의 항산화작용을 통한 당뇨 합병증을 예방할 것으로 사료된다.

Effect of chronic restraint stress and alpha-lipoic acid on lipid peroxidation and antioxidant enzyme activities in rat peripheral organs

Objectives The aim of this study was to evaluate the effect of chronic restraint stress and alpha-lipoic acid (LA) administration on lipid peroxidation and antioxidant enzyme activities in rat peripheral organs. Methods Forty male wistar rats, aged 3 months were randomized to one of the following groups: control, restraint stress, LA treated and restraint stress + LA treated. Chronic restraint stress was applied for 21 days (1 h/day) and LA (100 mg/kg/day) was administered intraperitoneally for the same period. Results Restraint stress had no statistically significant effect on lipid peroxidation, copper/zinc superoxide dismutase (Cu/Zn SOD), catalase (CAT) and glutathione peroxidase (GPx) activity in rat liver and heart, when compared to the control group. Lipid peroxidation, determined by measuring malondialdehyde (MDA) levels, was found to be increased in the kidney of restraint stress treated rats, compared to controls. Restraint stress-induced lipid peroxidation in the kidney was significantly decreased via LA treatment. Administration of LA also enhanced GPx and decreased Cu/Zn SOD activity in rat kidney, liver and heart, compared to the control group. Conclusions The presented data shows that LA is a protective agent against restraint stress—the inducer of lipid peroxidation in the kidney. These findings also suggest that LA-induced changes in antioxidant enzyme activities in rat peripheral organs may contribute to their versatile effects observed in vivo.

황금열수추출물이 DNCB로 유도된 알레르기성 접촉피부염 흰쥐의 항산화능 및 표피회복능에 미치는 영향

본 실험은 황금열수추출물이 알레르기성 접촉 피부염 유발 시 항산화활성, serum Ig E 농도와 표피회복능에 미치는 영향을 조사하기 위해 행해진 것으로 1-chloro-2,4-dinitrochlorobenzene(DNCB: 2.5% DNCB 1 mL로 감작, 4일 경과후 1% DNCB 1 mL로 유발) 처리로 알레르기성 접촉 피부염이 유발된 Sprague Dawley rat 수컷 흰쥐에 황금열수추출물(1 mL/㎏/day)을 경구투여한 다음 혈장과 간의 항산화활성, 혈중 Ig E 농도, 표피두께변화를 관찰하였다. DNCB 처리에 의해 지질과산화물 함량과 Ig E 농도, 표피두께가 증가하였으며 황금열수추출물의 경구투여에 의해 간의 지질과산화물 함량 감소, 혈중 Ig E 농도 감소, 표피두께가 저하되는 결과를 보였다. 이상의 결과로 미루어 황금열수추출물이 알레르기성 접촉피부염으로 유발된 rat의 체내 항산화활성과 Ig E 농도개선, 표피두께 개선에 효과가 있는 것으로 생각된다.

Croton cajucara BENTH. Leaf Extract Scavenges the Stable Free Radical DPPH and Protects Against Oxidative Stress Induced by Paraquat

Antioxidant effects of extracts from Croton cajucara BENTH. leaves was investigated in different in vitro and in vivo models. Extracts showed inhibitory radical scavenging activity against the stable radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) (75%, 43% and 25% of the standard trolox at 1, 10 and 100 mg/ml, respectively; IC50 218 mg/ml). Percentage survival of Saccharomyces cerevisiae cells treated with 10 mM paraquat increased by 21% and 55%, when 1 mg/ml and 10 mg/ml concentrations of the extract, respectively, were added. The cytosolic concentration of TBARS increased in animals treated with paraquat (+283%), while values did not significantly differ from the controls in rats additionally receiving the leaf extract. Paraquat administration also induced a significant increase in hydroperoxide-initiated chemiluminiscence (+76%), that was partially prevented by the leaf extract (+31%). Liver SOD activity was a 158% higher in animals receiving paraquat as compared to the controls. This effect was abolished by administration of the leaf extract. Paraquat administration did not significantly modify the activity of GPx or catalase. Croton cajucara extract increased GPx and catalase activities in paraquat treated-animals by 342% and 70%, respectively. Our results confirm that Croton cajucara leaf extract present radical scavenging activity and reduce oxidative stress induced by paraquat, suggesting the beneficial use as a potential source of antioxidant agents of natural origin.

1082. Delivery of Anti-Oxidative Enzyme Genes Protects Against Ischemia/Reperfusion-Induced Liver Injury in Mice

BACKGROUND: Hepatic ischemic/reperfusion (I/R) injury is characterized by the generation of reactive oxygen species (ROS), such as superoxide anions and hydrogen peroxide. The aim of this study is to investigate whether anti-oxidative gene delivery by our polycationic liposomes will be an effective approach for prevention of the injury. METHODS: Polycationic liposome-mediated extracellular superoxide dismutase (EC-SOD) or/and catalase gene delivery by portal vein injection was undertaken one day prior to warm I/R injury in mice. The effects of the gene delivery were determined 6 hours after starting reperfusion. RESULTS: Polycationic liposome-mediated anti-oxidative gene delivery led to marked hepatic transgene expression. There was a 56-fold increase in human EC-SOD gene expression in the liver 30 hours after injection of EC-SOD lipoplexes as shown by real time RT-PCR; Western blot analysis demonstrated a 10-fold increase in catalase protein levels in the liver as compared to controls. Liver SOD and catalase activity increased 16.6-fold and 9-fold, respectively. The overexpression of these two anti-oxidative genes significantly suppressed the subsequent I/R-induced acute liver injury as reflected by markedreduction of serum ALT levels (520±55 and 643±24 vs. 1217±193 units/ml, p<0.01). The I/R procedure significantly increased liver superoxide anions (699±83 vs. 20±13 RLU/sec/mg, p<0.01) as detected by a chemoluminescent method with a superoxide tracer, MCLA. These levels were markedly reduced to a nearly normal level (24±7 RLU/sec/mg) by the prior delivery of the EC-SOD gene. In addition, there were reduced liver malondialdehyde levels, and restored glutathione levels, in mice receiving either EC-SOD or catalase gene delivery. Moreover, the enhanced activation of nuclear factor-κB and AP-1 in hepatic I/R injury was minimized by the anti-oxidative gene delivery. The control lipoplexes did not affect the extent of liver injury and oxidant stress levels in this I/R model. The combination of EC-SOD and catalase lipoplex injection (in half amount of each plasmid) resulted in a slight improvement in hepatic I/R injury when compared to either alone. CONCLUSIONS: The findings demonstrate that polycationic liposome-mediated EC-SOD or catalase gene delivery led to high levels of the transgene activity in the liver, and markedly attenuated liver I/R injury. The protection is associated with enhanced anti-oxidative effects in the liver. To our knowledge, this is the first successful demonstration that polycationic liposome-mediated EC-SOD and/or catalase gene delivery ameliorates warm I/R-associated liver injury in mice. This approach may become a potential novel therapy to improve graft function and survival after liver transplantation.