Hepatic Antioxidant Enzyme Activities Research Articles

Preventive effect of phytoglycoprotein (27 kDa) on inflammatory factors at liver injury in cadmium chloride‐exposed ICR mice

Cadmium is one of the inflammation-related xenobiotics and has been regarded as a potent carcinogen. Gardenia jasminoides Ellis (GJE) has been used to cure inflammation in Korean folk medicine for a long time. The purpose of present study is the inhibitory effect of glycoprotein isolated from GJE (27 kDa) on inflammation mechanism in cadmium chloride-exposed ICR mice. We evaluated the activities of lactate dehydrogenase (LDH), alanine aminotransferase (ALT), and thiobarbituric acid-reactive substances (TBARS), activities of anti-oxidative enzymes [superoxide dismutase (SOD) and gluthathione peroxidase (GPx)], activities of c-Jun N-terminal protein kinase (JNK), heat shock protein 27 (Hsp27), activator protein (AP)-1, nuclear factor (NF)-κB and expression of inflammation-related mediators including tumor necrosis factor (TNF)-α and interleukin (IL)-6 in cadmium chloride-exposed ICR mice using immunoblot analysis, EMSA and RT-PCR. It notes that mice plasma was used to measure ALT, LDH, and TBARS after treatment with cadmium chloride alone or cadmium chloride under the pretreatment with GJE glycoprotein. Liver tissues were used to assess activities of anti-oxidant enzymes, SAPK/JNK, Hsp27, AP-1, NF-κB, TNF-α, and IL-6 in this study. The results obtained from this study revealed that GJE glycoprotein (10 mg/kg) decreased the levels of LDH, ALT and TBARS, whereas increased the activity of hepatic anti-oxidant enzymes (SOD and GPx) in cadmium chloride-exposed ICR mice. Moreover, it decreased the activity of JNK/AP-1, NF-κB, Hsp27, and pro-inflammatory cytokines (TNF-α and IL-6). Taken together, the results in this study suggest that GJE glycoprotein inhibits the expression of inflammation-related cytokines (TNF-α and IL-6) in cadmium chloride-exposed ICR mice.

Antioxidant and Hepatoprotective Potential of Soy Isoflavones Against CCl4 Induced Oxidative Stress and Early Tumor Events

In the present study we have evaluated the hepatoprotective efficacy of soy isoflavones (SIF), against carbon tetrachloride (CCl4) induced oxidative damage and early tumor response in male Wistar rats. Methods: Single treatment of CCl4 (1:1 v/v in corn oil was administered orally at dose of 1ml kg-1 body weight) induced oxidative stress and enhanced early tumor markers. Results: CCl4 treatment resulted in marked reduction of hepatic glutathione content and activities of hepatic anti-oxidant enzymes, viz., glutathione peroxidase (GPx), glutathione reductase (GR), catalase (CAT), glucose-6- phosphate dehydrogenase (G6PD) and phase-II metabolising enzymes such as glutathione-S-transferase (GST) and quinone reductase (QR) significantly as compared to control group (p

The intake of high fat diet with different trans fatty acid levels differentially induces oxidative stress and non alcoholic fatty liver disease (NAFLD) in rats.

BackgroundTrans-fatty acids (TFA) are known as a risk factor for coronary artery diseases, insulin resistance and obesity accompanied by systemic inflammation, the features of metabolic syndrome. Little is known about the effects on the liver induced by lipids and also few studies are focused on the effect of foods rich in TFAs on hepatic functions and oxidative stress. This study investigates whether high-fat diets with different TFA levels induce oxidative stress and liver dysfunction in rats.MethodsMale Wistar rats were divided randomly into four groups (n = 12/group): C receiving standard-chow; Experimental groups that were fed high-fat diet included 20% fresh soybean oil diet (FSO), 20% oxidized soybean oil diet (OSO) and 20% margarine diet (MG). Each group was kept on the treatment for 4 weeks.ResultsA liver damage was observed in rats fed with high-fat diet via increase of liver lipid peroxidation and decreased hepatic antioxidant enzyme activities (superoxide dismutase, catalase and glutathione peroxidase). The intake of oxidized oil led to higher levels of lipid peroxidation and a lower concentration of plasma antioxidants in comparison to rats fed with FSO. The higher inflammatory response in the liver was induced by MG diet. Liver histopathology from OSO and MG groups showed respectively moderate to severe cytoplasm vacuolation, hypatocyte hypertrophy, hepatocyte ballooning, and necroinflammation.ConclusionIt seems that a strong relationship exists between the consumption of TFA in the oxidized oils and lipid peroxidation and non alcoholic fatty liver disease (NAFLD). The extent of the peroxidative events in liver was also different depending on the fat source suggesting that feeding margarine with higher TFA levels may represent a direct source of oxidative stress for the organism. The present study provides evidence for a direct effect of TFA on NAFLD.

Antioxidative and hepatoprotective effects of fructo-oligosaccharide ind-galactose-treated Balb/cJ mice

Chronic subcutaneous (s.c.) administration of d-galactose (DG) to BL/6J mice has been shown to induce oxidative stress and is considered a model to mimic accelerated ageing. Fructo-oligosaccharide (FO) is a well-defined prebiotic and its fermentation by lactic acid bacteria has been shown to exert antioxidative capacity. The present study was aimed to determine whether FO attenuated DG-induced oxidative stress and hepatopathy in Balb/cJ mice. Mice (12 weeks of age, n 40) were divided into control (s.c. saline), DG (s.c. 1·2 g/kg body weight), DG+FO (5%, w/w) and DG+vitamin E (0·2%, w/w) groups and were killed after 52 d of treatment. Results indicated that DG significantly decreased the hepatic superoxide dismutase and glutathione peroxidase activities. These alterations were ameliorated both by FO and vitamin E. DG increased the hepatic TAG content approximately by 7·2% compared with the vehicle control, which was in agreement with the histological alteration. FO, similar to vitamin E, almost normalised the hepatic TAG content and ameliorated the histological characteristics of fatty liver. Similarly, the increased plasma alanine aminotransferase activity induced by DG was normalised by FO and vitamin E, respectively. Faecal bifidobacteria counts were greater in the DG+FO and DG+vitamin E groups compared with the DG group, respectively. In conclusion, the present study indicated that FO diminished the altered hepatic antioxidative enzyme activities and morphology caused by chronic DG administration in Balb/cJ mice, partially associated with its prebiotic role in the colon.

Butterbur (Petasites japonicusMax.) Extract Improves Lipid Profiles and Antioxidant Activities in Monosodiuml-Glutamate-Challenged Mice

We investigated the effect of the butanol fraction from the methanol extract of butterbur (Petasites japonicus Max.) (BMP) on the plasma lipid profiles and oxidative damage of liver in mice challenged with monosodium l-glutamate (MSG). ICR mice (6-8 weeks old, male) were fed BMP (0.1% or 0.3%) for 1 week, and on day 7, MSG (4 mg/g) was administered intraperitoneally to the mice. Administration of MSG resulted in a significant decrease of antioxidant biomarkers such as total glutathione level and antioxidant enzyme activities such as glutathione reductase (GR), glutathione peroxidase (GPx), glutathione S-transferase (GST), and quinone reductase (NQO1), whereas the thiobarbituric acid-reactive substances (TBARS) value was increased in liver tissue. However, BMP supplementation markedly enhanced the hepatic antioxidant enzyme activities, including GPx, GR, GST, and NQO1, whereas it lowered TBARS, compared to the MSG-treated group. Moreover, BMP supplementation decreased total cholesterol, atherogenic index, and low-density lipoprotein-cholesterol, compared to the MSG-treated group. Based on these results, it was proposed that BMP improve the plasma lipid profiles and decrease the oxidative stress by up-regulating the hepatic antioxidant enzymes in mice challenged with MSG.

Anti-Diabetic Effect of Red Ginseng-Chungkukjang with Green Laver or Sea Tangle

The hypoglycemic effects of red ginsgeng-chungkukjang plus seaweeds, green laver and sea tangle, in streptozotocin (STZ)-induced diabetic rats were investigated. Five groups of male Sprague-Dawley rats weighing 140±10 g (10 animals/group) were fed for four weeks with the following: nondiabetic control (NC group); STZ-induced diabetic (D group); diabetic rats fed 3% red ginseng (20%, w/w)-chungkukjang (D-RC group); diabetic rats fed RC containing 10% (w/w) green laver powder (D-RCG group); diabetic rats fed RC containing 10% (w/w) sea tangle powder (D-RCS group). Partially normalized body weight gain, FER, and blood glucose levels were observed in the D-RC, D-RCG and D-RCS groups as compared to the D group. In these three groups, serum levels of triglycerides, total cholesterol, and LDL-cholesterol were found to be lower than in the D group, whereas HDL-cholesterol levels increased. Serum insulin level in D was significantly lower than that of NC, although D-RC, D-RCG, and D-RCS almost recovered to the NC. Serum ALT activity was markedly increased in the D group, while the serum ALT levels in the D-RC, D-RCG, and D-RCS were almost the same as the NC group. Due to diabetes, hepatic xanthine oxidase (XO) activity was significantly increased and administration of red ginseng-chungkukjang or seaweeds resulted in decreased levels of the XO activity. Activity of hepatic antioxidant enzymes (superoxide dismutase and glutathione peroxidase) were significantly decreased in the D group, but the activity in the D-RC, D-RCG, and D-RCS groups were similar to that of the NC group. Results of the present study indicate that supplementation of red ginseng-chungkukjang with seaweed after the onset of diabetes ameliorated hyperglycemia via an increase in serum insulin.

Ameliorated effects of garlic (Allium sativum) on biomarkers of subchronic acrylamide hepatotoxicity and brain toxicity in rats

Acrylamide (ACR) exerts its toxicity through stimulation of the oxidative stress; yet, its effect on neurotransmitter catabolic enzymes has not been elucidated. We investigated the effects of ACR exposure on brain and hepatic tissues antioxidant enzymes activities and different markers such as, acetylcholinesterase (AChE), nitric oxide (NO), monoamine oxidase (MAO), and lipid profile, and to evaluate the protective effects of garlic against ACR toxicity. Male Sprague-Dawley rats were exposed to ACR (1 mg kg−1 body weight) with or without diet containing 1.5% of garlic powder for 40 days. ACR administration showed a decrease in AChE activity associated with an increase in MAO activity in both brain and hepatic tissues. In addition, ACR administration increased the lipid peroxidation and NO levels of both tissues while decreased the activities of glutathione (GSH), superoxide dismutase, and glutathione-S-transferase (GST). On the other hand, the activities of glutathione peroxidase (GPx) and catalase activities increased as a consequence of GSH depletion after ACR exposure. Finally, ACR exposure increased the brain and liver lipid profile of cholesterol, triglycerides and total lipid, while phospholipids level was decreased. Coadministration of garlic powder with ACR significantly attenuated oxidative stress, MAO activity, and inflammation in brain and hepatic tissues but did not ameliorate AChE activity. In conclusion, our results emphasized the role of garlic as a potential adjuvant therapy to prevent ACR neurotoxicity and hepatotoxicity.

Effects of l-Canavanine and ozone on vascular reactivity in septicemic rats

Septicemia leads to oxidative stress with overproduction of reactive-oxygen species (ROS) and consumption of endogenous antioxidant enzymes. We tested a twofold hypothesis: (1) does oxidative stress (OxS) induced by sepsis acting alone or in concert with augmented inflammatory processes contributes to sepsis-related vascular dysfunction, and, (2) whether ozone (O(3)) and L-canavanine (CAV) mitigate the negative impact of the aforementioned phenomena. We investigated the relative impact of treatment with CAV and/or O(3) on vascular OxS associated vascular functional changes in septicemic rats. For this study, 60 male Sprague-Dawley rats were used and divided into six experimental groups (n = 10): control group (C), sham-operated (Sham), septicemic rats (S), S rats treated with CAV (100 mg/kg. i.p; S + CAV), S rats treated with O(3) (1.2 mg/kg, i.p.; S + O(3)) and S rats treated with both O(3) and CAV (S + O(3) + CAV). After 22 h, the mean arterial blood pressure (MAP), the aortic ring vascular reactivity to phenylephrine, abdominal aortic blood flow (AABF), serum tumor necrosis factor-alpha (TNF-alpha) and plasma nitrite/nitrate (NOx) concentration were measured. In addition, hepatic antioxidant enzyme activities sodium dismutase (SOD) and glutathione peroxidase (GSH-Px) were estimated. Septicemia caused significant elevation of serum TNF-alpha (p < 0.001) and plasma NOx (p < 0.001) and significant (p < 0.001) reduction of AABF (p < 0.001), aortic vascular response to phenylephrine (p < 0.001), MAP (p < 0.001) and hepatic SOD and GSH-Px activity (p < 0.001) compared with the C group, while treatment with O(3) and/or CAV induced significant amelioration of all those increases. Abnormalities were attenuated to a similar extent with treatment with both O(3) and CAV. These results suggested that concomitant administration of O(3) and CAV alleviated the compromised vascular reactivity in septicemic conditions and prevent its progression into septic shock compared with each alone.

Biochemical and physiological responses in liver and muscle of rainbow trout after long-term exposure to propiconazole

In this study, the chronic toxic effects of PCZ, a triazole fungicide commonly present in surface and ground water, on morphological indices, ROS generation and RNA/DNA ratio in liver and white muscle of rainbow trout were investigated. Fish were exposed at sublethal concentrations of PCZ (0.2, 50 and 500μgL−1) for 7, 20 and 30d. Compared with the control, there were significant lower CF and HSI in fish exposed at the highest concentration of PCZ. ROS levels in both tissues increased significantly at higher PCZ concentrations (50 and 500μgL−1) after 20d and above, as well as in muscle of fish exposed at lowest PCZ concentration (0.2μgL−1) after 30d. The hepatic antioxidant enzymes (SOD and CAT) activities were induced significantly at higher concentrations (50, 500μgL−1) of PCZ after 20d and at 50μgL−1 after 30d. Additional, hepatic SOD activity was significantly induced at 0.2μgL−1 after 30d. Compared with the hepatic antioxidant enzymes activities in fish exposed to 50μgL−1 of PCZ, there was a decreasing trend in those exposed to 500μgL−1 after 30d exposure. However, both the antioxidant enzymes activities were significantly inhibited in muscle of fish exposed to 500μgL−1 PCZ after 30d. Moreover there was significant lower RNA/DNA ratio in both tissues after long-term exposure to higher concentration of PCZ. In short, environmental concentrations of PCZ could not induce obvious impacts on fish, but long-term exposure to higher concentrations of CBZ could affect seriously the health status of fish.

Hepatotoxicity induced by sub-acute exposure of rats to 2,4-Dichlorophenoxyacetic acid based herbicide “Désormone lourd”

“Désormone Lourd” is a 2,4-Dichlorophenoxyacetic based herbicide that includes 600 g/L 2,4-D. In this study we analyzed the toxic effects of 2,4-D on rat liver. Animals were daily treated with 15, 75 and 150 mg/kg, via oral gavage during 4 weeks. Hepatotoxicity was monitored by quantitative analysis of the serum enzymes markers of hepatotoxicity. Oxidative stress markers, catalase and glutathione reductase (CAT and GR), were analyzed in liver. We also investigated liver tissues histopathologically. Our results revealed that, when rats of 2,4-D treated groups were compared with the control group, the body weight decreased and the liver weight increased significantly at the end of the 4th week. The microscopic evaluation showed that 2,4-D induced hepatic cord disruption, focal necrosis, vessel dilation and pycnotic nucleus. Histological effects were found in all treated groups and their severity was dose dependent. Through sub-acute treatment, starting from the low to the high doses of 2,4-D, it was observed that there were effects on the activity of the serum enzyme markers, on TSP, Alb and the glycemia levels. We also observed a significant reduction in the hepatic antioxidant enzyme activities. To conclude, we can suggest that 2,4-D induces hepatoxicity and cellular alterations in rat.

Antioxidant effect of ethanol extract of powdered grape skin in C57BL/6J mice fed high‐fat diet

Grape seeds and skins are good sources of phytochemicals such as gallic acid, catechin, and epicatechin and are suitable raw materials for the production of antioxidative dietary supplements. And grape skins were a much more potent source than either grape pulp, juice or seeds. This study investigated the effect of ethanol extract of powdered grape skin antioxidant metabolism in high fat fed C57BL/6J mice. Five‐week‐old male C57BL/6J mice were randomly divided into two groups and fed high‐fat diet (HF control, 20%fat(w/w)) and with ethanol extract of powdered grape skin(GS) for 9 weeks. The plasma total cholesterol concentration was significantly higher in the HF group. Hepatic glutathione reductase, erythrocyte superoxide dismutase, catalase, glutathione reductase and glutathione peroxidase activities were significantly higher in the GS group than in the HF group. Erythrocyte thiobarbituric reactive substances (TBARS) level was tended to be lower in the GS group than in the HF group. Therefore, we suggest that grape skin is effective material on improvement of antioxidant metabolsim because GS supplementation induced the elevation of hepatic antioxidant enzyme activities, the reduction of erythrocyte lipid peroxide levels and hypocholesterolemic effects in high‐fat‐fed mice.

녹차추출물이 에탄올 투여에 의한 초기 간 손상에 미치는 영향

녹차 추출물이 에탄올에 의한 조기 간세포에 미치는 영향을 관찰하기 위해 흰쥐에 에탄올과 녹차 추출물을 투여하고 1시간 및 3시간 후 흰쥐의 간 글루타치온과 TNF-α량, 간항산화효소 활성도, 지질과산화물량 및 혈청 AST 및 ALT 활성도를 측정하였다. 또한 에탄올에 의한 만성 간 손상에<BR>미치는 영향을 관찰하기 위해서 에탄올과 녹차 추출물을 2일 간격 투여 20일 후 흰쥐의 간 글루타치온과 TNF-α량, 간 항산화 효소활성도, 지질과산화물량 및 혈청 AST 및 ALT 활성도를 측정하였다. 간 글루타치온량은 대조군에 비하여 에탄올 투여군에서 1시간, 3시간 및 20일 경과 후에 모두 감소되었고, 에탄올과 녹차추출물 혼합투여로 간 글루 타치온량이 에탄올 투여군에 비하여 증가되어 녹차추출물이 에탄올에 의한 간 글루타치온량 감소를 억제시킴을 알 수 있다. 간 TNF-α량은 에탄올 투여 1시간, 3시간 및 20일 경과 후 증가되었고, 녹차추출물과 에탄올 혼합투여군은 에<BR>탄올 투여군에 비하여 1시간, 3시간 및 20일 경과 후 모두 감소되어 녹차추출물 투여로 에탄올 투여에 의한 간조직의 TNF-α량 증가가 억제됨을 알 수 있다. 에탄올 투여군의 간 조직 TBARS량을 측정한 결과 에탄올을 투여한 후 1시간경과 및 3시간 경과 후 대조군과 유의한 차이가 없었다. 에탄올 투여군의 간 조직 항산화효소(SOD, catalase, GPx) 활성도를 측정한 결과 에탄올을 투여한 후 1시간 경과 및 3시간경과 후 대조군과 유의한 차이가 없었다. 에탄올 투여군의 혈청 ALT와 AST 활성도를 측정한 결과 에탄올을 투여한 후 1시간 경과 및 3시간 경과 후 대조군과 유의한 차이가 없었다. 이상의 실험 결과 녹차 추출물은 간에서 에탄올에 의해서 조기에 일어나는 글루타치온량 감소 및 TNF-α량증가를 억제시키는 작용이 있는 것을 알 수 있는데, 녹차 추출물의 이러한 효과는 녹차 추출물이 에탄올에 의한 간 손상을 억제하는데 중요한 작용을 할 수 있을 것으로 기대된다. 녹차 추출물에 함유된 에탄올에 의한 간 손상 방지 물질의 검색과 글루타치온 및 TNF-α에 대한 작용 기전 및 특성에 대한 연구가 계속된다면 우수한 간 손상 방지작용을 가진 물질이 개발될 수 있을 것으로 추측된다.

Effects of Oxidized Cooking Oil and α-Lipoic Acid on Liver Antioxidants: Enzyme Activities and Lipid Peroxidation in Rats Fed a High Fat Diet

The effects of administration of oxidized rapeseed oil and α-lipoic acid on activities of hepatic antioxidant enzymes and lipid peroxidation were studied in laboratory rats. There was an increase of the activities of superoxide dismutase, glutathione peroxidase, glutathione reductase, and glucose-6-phosphate dehydrogenase in rats fed a high fat diet to which 10% oxidized oil was added. Administration of α-lipoic acid resulted in a decrease of the activities of these enzymes. Addition of oxidized oil also resulted in increased production of oxygen radicals, evidenced by elevated malondialdehyde production. Such effect was counteracted by administration of α-lipoic acid.

Effects of alendronate and risedronate therapy on hepatic antioxidant enzyme activity and lipid peroxidation in ovariectomized rats

To evaluate the effects of alendronate (ALN) and risedronate (RIS), which are agents for preventing and treating postmenopausal osteoporosis, on hepatic antioxidant enzyme activity and lipid peroxidation in ovariectomized rats. Materials and methods: Thirty-two female rats were randomly assigned to 4 separate groups. All of the groups, except the control group, were ovariectomized. Included in the 4 groups were a control group (C), an ovariectomized group (OVX), an ovariectomized group treated with alendronate (OVX-ALN), and an ovariectomized group treated with risedronate (OVX-RIS). Ten weeks after an ovariectomy, the OVX-ALN rats were administered 1.75 mg/kg of their body weight with alendronate sodium; and the OVX-RIS rats were administered 0.5 mg/kg of their body weight with risedronate sodium. Both doses were administered by gavage twice per week for 12 weeks. At the end of the treatment period, the liver enzyme activity levels of superoxide dismutase (SOD) and catalase (CAT) and malondialdehyde (MDA) levels were measured. Results: There were significantly elevated levels of MDA observed in the OVX and OVX-ALN groups, whereas the MDA concentration significantly decreased in the OVX-RIS group when compared to the control animals. The SOD activity was significantly higher in the OVX and OVX-ALN groups, but there was no statistically significant difference in the SOD activity in the OVX-RIS group when compared with that of the control group. Moreover, CAT activity declined significantly in the OVX group and was elevated in the OVX-ALN group, according to the control group. No significant change in CAT activity was observed in the OVX-RIS group. Conclusion: Alendronate increases the effect of ovariectomy on lipid peroxidation, and induces oxidative stress; however, risedronate prevents oxidative stress caused by an ovariectomy.

Effect of Diashis, a polyherbal formulation, in streptozotocin-induced diabetic male albino rats.

This study focuses on the effect of ‘Diashis’, a polyherbal formulation composed of eight medicinal plants for the management of streptozotocin (STZ)-induced diabetes in rats. As oxidative stress is one of the consequences of diabetes, the activities of hepatic antioxidant enzymes and metabolic enzymes were evaluated. Treatment with ‘Diashis’ in STZ-induced diabetic rats resulted in a significant (P < 0.01) recovery in the activities of hepatic hexokinase, glucose-6-phosphate dehydrogenase, and glucose-6-phosphatase along with correction in the levels of fasting blood glucose, glycated hemoglobin, and liver and skeletal muscle glycogen. The oxidative stress status in the liver was corrected by ‘Diashis’ which was highlighted by the recovery in the activities of catalase, peroxidase, and glutathione-S-transferase along with the correction in the quantity of thiobarbituric acid-reactive substances and conjugated diene. ‘Diashis’ was not found to have any metabolic toxicity. The antidiabetic effects of ‘Diashis’ were compared with those of the antidiabetic drug, ‘Glibenclamide’.

Antioxidant and hepatic protective effects of lotus root hot water extract with taurine supplementation in rats fed a high fat diet

BackgroundNelumbo nucifera, known as sacred lotus, is a well-known medicinal plant and this lotus root is commonly used as food compared to different parts of this plant. This study was conducted to investigate the antioxidant and hepatic protective effects of lotus root hot water extract with taurine supplementation in high fat diet-induced obese rats.MethodsThirty-two male Sprague-Dawley rats (4-week-old) were randomly divided into four groups (n=8) for 6 weeks (normal diet, N group; high fat diet, HF group; high fat diet + lotus root hot water extract, HFR group; high fat diet + lotus root hot water extract + taurine, HFRT group). Lotus root hot water extract was orally administrated (400mg/kg/day) to HFR and HFRT groups and the same amount of distilled water was orally administered to N and HF groups. Taurine was supplemented by dissolving in feed water (3% w/v).ResultsThe activities of glutamate oxaloacetate transaminase and glutamate pyruvate transaminase in serum were lower in HFR and HFRT groups compared to HF group. Thiobarbituric acid reactive substance contents in all groups fed a high fat diet were higher compared to N group. The activities of hepatic antioxidant enzymes were higher in HFR and HFRT groups compared to HF group.ConclusionsThese results suggest that lotus root hot water extract with taurine supplementation shows antioxidant and hepatic protective effects in high fat diet-induced obese rats.

Influence of Oryzanol and Ferulic Acid on the Lipid Metabolism and Antioxidative Status in High Fat-Fed Mice

The comparative effects of oryzanol and ferulic acid on the lipid metabolism and antioxidative status of high fat-fed mice were investigated. The mice were given a diet containing 17% fat (HF), supplemented with oryzanol (HF-O) or ferulic acid for 7 weeks. The control mice (NC) were fed with normal diet. The HF mice exhibited increased body weight gain, plasma and hepatic total cholesterol and triglyceride concentrations, and lipid peroxidation rate, and reduced high-density lipoprotein cholesterol level. In general, they also showed lower hepatic antioxidant and higher lipid-regulating enzymes activities relative to that of NC group. Addition of oryzanol or ferulic acid in the diet counteracted these high fat-induced hyperlipidemia and oxidative stress via increased faecal lipid excretion and regulation of antioxidant and lipogenic enzymes activities. This study illustrates that oryzanol and ferulic acid have relatively similar hypolipidemic actions and could be effective in lowering the risk of high fat diet-induced obesity.

Effects of olive oil and its fractions on oxidative stress and the liver's fatty acid composition in 2,4-Dichlorophenoxyacetic acid-treated rats

BackgroundOlive oil's beneficial effects are not only related to its high content of oleic acid, but also to the antioxidant potential of its polyphenols. In this study, we assess the effects of virgin olive oil and its fractions on 2,4-D- induced oxidative damage in the liver of rats.MethodsMale Wistar rats were randomly divided into eight groups of ten each: (C) a control group, (D) group that received 2,4-D (5 mg/kg b.w.), (D/EVOO) group treated with 2,4-D plus extra virgin olive oil, (D/OOHF) group that received 2,4-D plus hydrophilic fraction, (D/OOLF) group treated with 2,4-D plus lipophilic fraction, (EVOO) group that received only extra virgin olive oil, (OOHF) group given hydrophilic fraction and (OOLF) group treated with lipophilic fraction. These components were daily administered by gavage for 4 weeks.ResultsA significant liver damage was observed in rats treated with 2,4-D via increased serum levels of transaminases and alkaline phosphatase, hepatic lipid peroxidation and decreased hepatic antioxidant enzyme activities, namely, superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase. The liver's fatty acid composition was also significantly modified with 2,4-D exposure. However, extra virgin olive oil and hydrophilic fraction intake during 2,4-D treatment induced a significant increase in the antioxidant enzyme activities and a decrease in the conjugated dienes (CD) and thiobarbituric acid-reactive substances (TBARs) levels in the liver. The lipophilic fraction supplemented to 2,4-D- treated rats did not show any improvement in the liver oxidative status while a marked improvement was detected in the hepatic fatty acid composition of rats supplemented with olive oil and the two fractions.ConclusionWe concluded that the protective effect of olive oil against oxidative damage induced by 2,4-D is mainly related to the antioxidant potential of its hydrophilic fraction.

Antihyperglycemic and Antioxidative Effects of New Herbal Formula in Streptozotocin-Induced Diabetic Rats

Herbal prescriptions have been recognized as potentially valid by the scientific medical establishment, and their use has been increasing. The present study investigated the antidiabetic effects of a new herbal formula (NHF) consisting of Polygonati Rhizoma, Rehmanniae Radix, Salviae Miltiorrhizae Radix, Puerariae Radix, Schizandrae Fructus, and Glycyrrhizae Radix. Streptozotocin-induced diabetic rats were orally administered NHF (300 mg/kg of body weight/day) for 4 weeks. The diabetic rats exhibited hyperglycemia, increased food and water intake, loss of body weight gain, elevated hepatic thiobarbituric acid-reactive substances (TBARS), and decreased activities of hepatic antioxidant enzymes (such as superoxide dismutase [SOD], catalase [CAT], and glutathione peroxidase [GSH-Px]), level of mRNA of glucose transporter (GLUT) 4 in soleus muscle, and numbers of insulin-positive cells and the size of beta-cells in pancreas. Administration of NHF significantly decreased the blood glucose level and the food and water intake and considerably increased the body weights of diabetic rats. Also, NHF treatment significantly increased plasma insulin levels and the number and size of insulin-immunoreactive cells in the pancreas of diabetic rats. Administration of NHF significantly lowered the levels of TBARS and increased the activities of SOD, CAT, and GSH-Px in the liver of diabetic rats. In addition, treatment with NHF increased the mRNA levels of GLUT4 in soleus muscle. Therefore NHF may be an effective preventive and therapeutic agent for diabetes mellitus.

Hepatic Histopathological Characteristics and Antioxidant Response of Phytoplanktivorous Silver Carp Intraperitoneally Injected with Extracted Microcystins

To investigate the hispathological characteristics and antioxidant responses in liver of silver carp after intraperitoneal administration of microcystins (MCs) for further understanding hepatic intoxication and antioxidation mechanism in fish. Phytoplanktivorous silver carp was injected intraperitoneally (i.p.) with extracted hepatotoxic microcystins (mainly MC-RR and -LR) at a dose of 1000 microg MC-LReq./kg body weight, and liver histopathological changes and antioxidant responses were studied at 1, 3, 12, 24, and 48 h, respectively, after injection. The damage to liver structure and the activities of hepatic antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), and glutathione peroxide (GPX) were increased in a time-dependent manner. In terms of clinical and histological signs of intoxication and LD50 (i.p.) dose of MC-LR, silver carp appears rather resistant to MCs exposure than other fishes. Also, the significantly increased SOD activity in the liver of silver carp suggests a higher degree of response to MCs exposure than CAT and GPX.