Effects of lipoic acid on spleen oxidative stress after LPS administration

BackgroundBacterial endotoxin (lipopolysaccharide – LPS) is a strong modulator of the immune system that plays a crucial role in the pathogenesis of endotoxic shock. The aim of the study was to investigate the effects of lipoic acid (LA) on oxidative stress markers in spleen homogenates obtained from LPS-induced endotoxic shock rats.MethodsThe animals were treated with saline or lipoic acid (LA) (60 or 100 mg/kg b.w. iv) 30 min before or 30 min after LPS administration (30 mg/kg b.w. iv). Five hours after LPS, LA or saline administration, the animals were euthanized and their spleens were isolated for measurements.ResultsThe LPS-treated animals developed oxidative stress, indicated by a significant increase in thiobarbituric acid-reactive substances (TBARS) and hydrogen peroxide (H₂O₂) concentrations (p < 0.001) as well as an insignificant decrease in the level of sulfhydryl groups (-SH groups) and the glutathione redox ratio [reduced glutathione (GSH) to oxidized glutathione (GSSG) ratio] (p < 0.02) as compared with control group. Treatment with LA (60 or 100 mg/kg) before or after LPS administration resulted in an increase in -SH group content (p < 0.01) and a decrease in TBARS and H₂O₂ concentration in the spleen as compared with LPS group (p < 0.001). LA (60 or 100 mg/kg) before LPS administration decreased the level of GSSG (p < 0.05) and increased the level of GSH in spleen homogenates (p < 0.05), resulting in an increase in the GSH/GSSG ratio compared with the LPS group (p < 0.01). It also improved the LPS-induced increase in the spleen weight (SW) to body weight (BW) ratio (p < 0.001 vs. control).ConclusionThe present results have shown that LAis endowed with antioxidant properties that are protective in the spleen against the deleterious actions of Gram-negative bacterial endotoxin.     

Co-administration of adjuvants along with Moringa oleifera attenuates beryllium-induced oxidative stress and histopathological alterations in rats

Abstract

Context: Moringa oleifera Lam. (Moringaceae) is a rich source of antioxidants. All parts of the plant are medicinally important and have been used as traditional medicine for a variety of human ailments in India.

Objective: Therapeutic efficacy of adjuvants with M. oleifera (MO) root extract was investigated against beryllium-induced oxidative stress.

Materials and methods: Hydroalcoholic (50% v/v) root extract of M. oleifera (150?mg/kg, p.o.) alone and combinations of M. oleifera with either piperine (2.5?mg/kg, p.o.) or curcumin (5.0?mg/kg, p.o.) daily for 1 week were administered in experimental rats against beryllium toxicity (1.0?mg/kg, i.p. daily for 5 weeks). Oxidative stress parameters including blood sugar, G-6-Pase in liver, and DNA damage were analyzed. Histopathological changes in liver and kidney were also observed.

Results: Beryllium enhanced lipid peroxidation (LPO), depleted reduced glutathione (GSH) and antioxidant enzymes activities, decreased blood sugar and G-6-Pase activity, and did not damage DNA. Histologically, liver was observed with structural loss and disintegration of hepatocytes, heavy vacuolation in hepatocytes, and kidney was observed with constriction of glomeruli and hypertrophy in epithelial cells of uriniferous tubules. Therapy of M. oleifera with piperine was effective; however, combination of M. oleifera with curcumin showed better therapeutic effect by reduction of LPO, elevated GSH level, maintained antioxidant enzymes activities, restored blood sugar, and G-6-Pase activity in liver together with almost normal histoarchitecture of liver and kidney.

Discussion and conclusion: Curcumin enhanced therapeutic efficacy of M. oleifera root extract and showed better antioxidant potential against beryllium toxicity.     

Asiatic acid attenuates pre-neoplastic lesions,oxidative stress,biotransforming enzymes and histopathological alterations in 1,2-dimethylhydrazine-induced experimental rat colon carcinogenesis

Asiatic acid (AA), a pentacyclic triterpenoid, derived from the tropical medicinal plant Centella asiatica is known to exhibit numerous pharmacological properties. We hypothesized that AA will have chemopreventive potential against 1,2-dimethylhydrazine (DMH)-induced experimental colon carcinogenesis in male Wistar rats. Rats were arbitrarily divided into six groups. Group I rats were processed as control. Group II rats received AA (8?mg/kg b.w., p.o.) and groups III–VI rats received subcutaneous injections of DMH (20?mg/kg b.w.) once a week, for the first four weeks. In addition, groups IV–VI rats received AA at the doses of 2, 4 and 8?mg/kg b.w., respectively, for 16 weeks. Our results discovered that supplementation with AA to the DMH-exposed rats significantly decreased the incidence of polyps and Aberrant crypt foci (ACF) as compared to the DMH-alone-exposed rats. Moreover, in the AA-supplemented DMH-exposed rats, we ascertained increased activities of the antioxidants and decreased levels of lipid peroxidation (LPO) in the liver and circulation and enhanced levels of both LPO and antioxidants in the colon, which were altered in the DMH-alone-exposed rats. Furthermore, we also observed altered activities of vitamins C and E and biotransforming enzymes in DMH-alone-exposed rats, which were reversed on AA supplementation. All the observations were supported by our histological findings. Thus, we can conclude that, AA could be used as an effective chemopreventive agent against DMH-induced colon carcinogenesis.     

Crocin attenuates cisplatin-induced renal oxidative stress in rats

Reactive oxygen species (ROS) and oxidative damage are the most important factors in cisplatin-induced acute renal failure. This study examined the protective effects of crocin against cisplatin-induced renal oxidative stress in rat. Animals were divided into five groups (n = 6). Group 1 received normal saline (2 ml/day, i.p.). Group 2 received a single dose of cisplatin (5 mg/kg, i.p.). Groups 3–5 received crocin (100, 200, and 400 mg/kg, i.p., respectively) for four consecutive days beginning 1-h before a single dose of cisplatin (5 mg/kg) on day 1. On day 5, blood samples were drawn and kidneys were removed for histopathological, biochemical and RT-PCR examinations. Twenty four hours urinary chemistries were measured. Blood urea and creatinine and urinary glucose and protein concentrations in crocin-treated groups were significantly lower compared to the cisplatin-treated group. Histopathological studies showed massive damage in the S₃ segment of proximal tubules in cisplatin-treated group but not in crocin-treated groups. Crocin treatment resulted in a significant reduction in malondialdehyde (MDA) concentration and produced a significant elevation in total thiol and glutathione peroxidase concentrations. There was a significant elevation in the mRNA expression of glutathione peroxidase in crocin-treated groups. The results suggest that crocin attenuates cisplatin-induced renal oxidative stress in rats.     

Boron attenuates malathion-induced oxidative stress and acetylcholinesterase inhibition in rats

Organophosphorus compounds cause oxidative stress and lead to alterations in antioxidant status in organisms. In this study, the effects of subchronic exposure to malathion and the protective effects of boron (B) were evaluated in 48 Wistar rats, which were divided equally into six groups. For 28?d, the control group received a normal diet and tap water, the corn oil group received a normal diet and 0.5?mL of corn oil by gastric gavage and the malathion group received a normal diet and malathion (100?mg/kg/d) by gastric gavage. During the same period, each of the three other groups received a different dosage of B (5, 10 and 20?mg/kg/d, respectively) and malathion (100?mg/kg/d) by gastric gavage. Malathion administration during the period increased malondialdehyde, nitric oxide and 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels, as well as markers of liver function, yet decreased acetylcholinesterase, reduced glutathione, superoxide dismutase, and catalase activities in blood, liver, kidney and brain tissues. Administration of B in a dose-dependent manner also reversed malathion-induced oxidative stress, lipid peroxidation (LPO) and antioxidant enzyme activity. Moreover, B exhibited protective action against malathion-induced histopathological changes in liver, kidney and brain tissues. These results demonstrate that, if used in a dose-dependent manner, B decreases malathion-induced oxidative stress, enhances the antioxidant defense mechanism and regenerates tissues in rats.     

Attenuation of beryllium induced hepatorenal dysfunction and oxidative stress in rodents by combined effect of gallic acid and piperine

We determined a minimum effective dose of gallic acid (3,4,5-trihydroxy benzoic acid; 50 mg/ kg, i.p.) and piperine (10 mg/kg, p.o.) through their therapeutic potential and further evaluated them individually and in combination against beryllium-induced biochemical alterations and oxidative stress consequences in female albino rats. The administration of beryllium altered blood biochemical variables by significantly depleting hemoglobin, albumin and urea, whereas it enhanced bilirubin and creatinine. The release of serum transaminase, lactate dehydrogenase and gamma-glutamyl transpeptidase was significantly greater, and was concomitant with a decrease in serum alkaline phosphatase. A significant increase in lipid peroxidation and a decrease in glutathione, superoxide dismutase and catalase in the liver and kidney was an indication of oxidative stress due to beryllium exposure. Individual administration of gallic acid and piperine moderately reversed the altered biochemical variables, whereas the combination of these was found to completely reverse the beryllium-induced biochemical alterations and oxidative stress consequences. We concluded that gallic acid exerts a synergistic effect when administered with piperine and provides a more pronounced therapeutic potential in reducing beryllium-induced hepatorenal dysfunction and oxidative stress consequences.     

Lipoic acid attenuates Aroclor 1260‐induced hepatotoxicity in adult rats

The present study was aimed to investigate the mechanistic aspect of Aroclor 1260‐induced hepatotoxicity and its protection by lipoic acid. The adult male Albino rats were divided into six groups. Group I served as control. Group II received lipoic acid (35 mg/kg/day). Aroclor 1260 was given to rats by oral gavage at doses 20, 40, or 60 mg/kg/day (Groups III, IV, and V, respectively). Group VI was pretreated with lipoic acid (35 mg/kg/day) 24 h before Aroclor 1260 (40 mg/kg/day). Treatment in all groups was continued for further 15 consecutive days. Serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase activities and total bilirubin, total cholesterol, and triglycerides were significantly increased while total protein, total albumin, and high‐density lipoprotein were significantly decreased. Hydrogen peroxide production and lipid peroxidation were significantly increased while superoxide dismutase and catalase activities and reduced glutathione (GSH) content was significantly decreased in liver. Caspase‐3 & ‐9 activities were significantly increased in liver. Lipoic acid pretreatment significantly reverted all these abnormalities toward their normal levels. In conclusion, Aroclor 1260 induced liver dysfunction, at least in part, by induction of oxidative stress. Apoptotic effect of hepatic cells is involved in Aroclor 1260‐induced liver injury. Lipoic acid could protect rats against Aroclor 1260‐induced hepatotoxicity. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 913–922, 2016.     

熊果酸对动脉粥样硬化大鼠氧化应激和炎性反应的影响

目的 研究熊果酸(UA)对动脉粥样硬化(AS)大鼠氧化应激和炎性反应的抑制作用,并探讨其机制.方法 采用高脂饲料喂养结合腹腔注射VD3的方法建立早期AS大鼠模型,并分别灌胃给予UA(10、20、40 mg· kg-1· d-1)和辛伐他汀(SV, 1.8 mg· kg-1· d-1)进行干预,作为干预组,另设模型组和健康对照组(喂食正常饲料并腹腔注射生理盐水).采用比色法测定血清中抗氧化酶[超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)]活性和丙二醛(MDA)、活性氧簇(ROS)含量;酶联免疫法(ELISA)测定血浆中炎性细胞因子[C反应蛋白(CRP)、肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)、白细胞介素-10(IL-10)]含量;苏木精-尹红(HE)染色观察主动脉形态结构改变并进行病变分级.结果 UA(20、40 mg· kg -1· d-1)同步干预组大鼠血清中 SOD、CAT 活性较模型组显著升高[(318.3 ±29.4)、(12.3 ±2.4)U· mL-1vs(249.3 ±25.1)、(9.3 ±1.7)U· mL-1],MDA、ROS含量显著降低[(31.2 ±5.1)vs(49.6 ±7.0) mmol· L-1和(291.3 ±31.8)vs(402.9 ±35.7)U· mL-1],且UA 40 mg· kg -1· d-1干预组GSH-Px活性显著升高[(809.3 ± 58.4)vs(676.1 ±48.5)U· mL-1];UA(20、40 mg· kg-1· d-1)同步干预组大鼠血浆中CRP、TNF-α、IL-1β、IL-6含量较模型组均显著降低,且UA 40 mg· kg-1· d-1干预组IL-10含量显著升高[(37.6 ±4.9)vs(23.9 ±3.2)ng· L-1];UA同步干预组大鼠主动脉形态结构改变较模型组明显改善、病变评分显著降低,其中以UA 40 mg· kg-1· d-1干预组效果最为显著.结论UA可能通过抑制氧化应激损伤和炎性反应而对AS大鼠起到一定保护作用.     

Immunosuppression and oxidative stress induced by subchronic exposure to carbosulfan in rat spleen: immunomodulatory and antioxidant role of N-acetylcysteine

The present study was designed to determine the immunosuppressive effects of carbosulfan (CB) and their relationship with an increased formation of reactive oxygen species in rat. Further, we aimed to evaluate the protective effects of N-acetyl-cysteine (NAC) against immunopathological changes induced by CB. Carbosulfan (25?mg/kg) and NAC (2?g/l) were given daily to rats during 30 days, via oral gavage and drinking water, respectively. Cell-mediated immune function, cytokines production, biomarkers of cell redox state maintenance, lipid peroxidation and the activities of antioxidant enzymes were measured in the spleen. Our data showed an increase in WBC percent (28.42%), a reduction in spleen CD8 T-lymphocytes (?85.63%) and a decrease in immunosuppressive cytokines production such as INF-gamma and IL-4. There was a switch from Th1-type to Th2-type cytokines with an unbalance toward anti-inflammatory cytokines. Moreover, a significant decrease in reduced glutathione (?71.68%) and total thiols (?39.81%) levels were observed in treated rats. Conversely, malondialdehyde level in spleen was increased (?42.3%), while glutathione-S-transferase, glutathione peroxidase, superoxide dismutase and catalase activities were depleted. Our results suggest that subchronic CB administration affects cellular enzyme and non-enzyme-mediated antioxidant defense systems and promotes immunotoxicity in rat. On the other hand, our data showed protective effects of NAC. Indeed, there was a recovery of oxidative stress markers and cytokines production. The use of NAC, in our study, as a therapeutic agent showed interesting results against CB toxicity.     

Edaravone attenuates brain damage in rats after acute CO poisoning through inhibiting apoptosis and oxidative stress

Acute carbon monoxide (CO) poisoning is the most common cause of death from poisoning all over the world and may result in neuropathologic and neurophysiologic changes. Acute brain damage and delayed encephalopathy are the most serious complication, yet their pathogenesis is poorly understood. The present study aimed to evaluate the neuroprotective effects of Edaravone against apoptosis and oxidative stress after acute CO poisoning. The rat model of CO poisoning was established in a hyperbaric oxygen chamber by exposed to CO. Ultrastructure changes were observed by transmission electron microscopy (TEM). TUNEL stain was used to assess apoptosis. Immunohistochemistry and immunofluorescence double stain were used to evaluate the expression levels of heme oxygenase‐1 (HO‐1) and nuclear factor erythroid 2‐related factor 2 (Nrf‐2) protein and their relationship. By dynamically monitored the carboxyhemoglobin (HbCO) level in blood, we successfully established rat model of severe CO poisoning. Ultrastructure changes, including chromatin condensation, cytoplasm dissolution, vacuoles formation, nucleus membrane and cell organelles decomposition, could be observed after CO poisoning. Edaravone could improve the ultrastructure damage. CO poisoning could induce apoptosis. Apoptotic cells were widely distributed in cortex, striatum and hippocampus. Edaravone treatment attenuated neuronal apoptosis as compared with the poisoning group (P < 0.01). Basal expressions of HO‐1 and Nrf‐2 proteins were found in normal brain tissue. CO poisoning could activate HO‐1/Nrf‐2 pathway, start oxidative stress response. After the administration of Edaravone, the expression of HO‐1 and Nrf‐2 significantly increased (P < 0.01). These findings suggest that Edaravone may inhibit apoptosis, activate the Keapl‐Nrf/ARE pathway, and thus improve the ultrastructure damage and neurophysiologic changes following acute CO poisoning. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 372–379, 2016.     

Ellagic acid ameliorates nickel induced biochemical alterations: diminution of oxidative stress

Nickel, a major environmental pollutant is known for its clastogenic, toxic and carcinogenic potentials. The present investigation shows that ellagic acid proves to be exceptional in the amelioration of the nickel-induced biochemical alterations in serum, liver and kidney. Administration of nickel (250 micromol Ni/kg body wt) to female Wistar rats, resulted in increase in the reduced glutathione (GSH) content [kidney (*P<0.05) and liver (**P<0.001)] and Glutathione-S-transferase (GST) and glutathione reductase (GR) activities [kidney and liver, (**P<0.001)]. Ellagic acid treatment to the intoxicated rats leads to the formation of soluble ellagic acid-metal complex which facilitates excretion of nickel from the cell or tissue, thus ameliorating nickel-induced toxicity, as evident from the down regulation of GSH content, GST and GR activities with concomitant restoration of glutathione peroxidase (GPx) activity in liver and kidney. Our data shows that ellagic acid maintains cell membrane integrity through sequestration of metal ions from the extracellular fluid, as evident from the alleviated levels of serum glutamate oxaloacetate transaminase, (SGOT), serum glutamate pyruvate transaminase (SGPT) and lactate dehydrogenase (LDH) when compared to nickel treated group. Similarly, the enhanced blood urea nitrogen (BUN) and serum creatinine levels that are indicative of renal injury showed a reduction of about 45 and 40%, respectively. The data also show that treatment of ellagic acid after 30 min of nickel administration exhibits maximum inhibition in a dose-dependent manner. In summary, our data suggests that ellagic acid act as an effective chelating agent in suppressing nickel-induced renal and hepatic biochemical alterations.     

Ascorbic acid attenuates cognitive impairment and brain oxidative stress in ovariectomized mice

Background

Menopause is associated with increased oxidative stress and memory impairment. Based on the antioxidant property of ascorbic acid (AA), It’s effect on cognitive function, the serum level of the brain-derived neurotrophic factor (BDNF) and the activity of antioxidant enzymes within the brain in ovariectomized (OVX) mice was investigated.

Inhibition of the renin-angiotensin system attenuates the development of liver fibrosis and oxidative stress in rats

1. The present study was designed to investigate the potential antifibrotic and anti-oxidant effects of lisinopril, fosinopril and losartan in an experimental rat model of liver injury using carbon tetrachloride (CCl(4)). 2. First, the potential hepatoprotective dose of each drug was screened against CCl(4)-induced acute hepatotoxicity. Then, we chose the minimum hepatoprotective dose of each drug to further investigate the mechanisms involved in the hepatoprotection using a chronic model of hepatotoxicity induced by CCl(4). 3. Liver function was assessed in addition to histopathological examination. Furthermore, oxidative stress markers (reduced glutathione (GSH) and lipid peroxides levels) and markers of fibrosis (hydroxyproline content and liver fibrosis area) were assessed. 4. It was found that treatment of animals with different drugs concomitantly with CCl(4) significantly counteracted the changes in liver function induced by CCl(4) (except fosinopril). In addition, the drugs ameliorated the histopathological changes induced by CCl(4). All drugs significantly counteracted lipid peroxidation and GSH depletion (except fosinopril) compared with the CCl(4)-intoxicated group. Moreover, the drugs studied significantly reduced liver hydroxyproline levels and the area of fibrosis compared with the CCl(4)-intoxicated group. 5. In conclusion, the present study provides evidence for the hepatoprotective effect of lisinopril, fosinopril and losartan. Both lisinopril and losartan was found to have better hepatoprotective potential than fosinopril against CCl(4)-induced hepatotoxicity. These hepatoprotective effects can be explained on the basis of anti-oxidant and antifibrotic mechanisms, mainly enhancement of GSH and reduction of lipid peroxidation and fibrosis.     

An increase of oxidative stress markers and the alteration of the antioxidant enzymatic system are associated with spleen damage caused by methimazole-induced hypothyroidism

Methimazole is the most widely used antithyroid drug in Europe and North America, but it causes several undesirable side effects, such as hematological dysfunctions and immunosuppression. Our aim in this work was to compare, over a time course, markers of oxidative stress, the redox environment, the antioxidant enzymatic system, and the glutathione cycle in the spleen of rats with methimazole- or thyroidectomy-caused hypothyroidism. We used 70-male Wistar rats divided into four groups: 1) euthyroid; 2) sham thyroidectomy; 3) thyroidectomy-caused hypothyroidism, with parathyroid reimplant; and 4) methimazole-caused hypothyroidism. Five rats of the euthyroid- and methimazole-caused hypothyroidism groups were killed at the end of weeks 1, 2, 3, and 4 after treatment, and 5 rats of the sham thyroidectomy and thyroidectomy-caused hypothyroidism groups were killed at the end of weeks 2, 4, and 8 after the surgical procedure. Each spleen was excised and stored at ?70°C until oxidative stress, REDOX environment, and the antioxidant enzymatic-system markers were tested. The histological study showed that only methimazole-induced hypothyroidism caused cell damage. This damage was associated with an increase of oxidative-stress markers that were not compensated for by the antioxidant system. The increase of the glutathione-cycle enzymes was insufficient to prevent oxidative-stress markers. Methimazole causes oxidative stress and cell damage in the spleen, whereas hypothyroidism per se does not cause cell damage in this organ. Therefore, it is necessary to develop new antithyroid drugs without causing oxidative stress and cellular damage.     

Modulatory effects of quercetin on liver histopathological,biochemical, hematological,oxidative stress and DNA alterations in rats exposed to graded doses of score 250

This study investigated the morphological, biochemical and molecular aspects of liver injury in rats after the exposure to difenoconazole and the protective effects of quercetin against hepatotoxicity and genotoxicity induced by this fungicide. Rats were given graded doses of difenoconazole associated or not to quercetin daily for 20 days. Our results showed a significant increase in PLT (platelets) and WBC (white blood cells) in rats treated with higher doses of difenoconazole (1/38 and 1/9 of LD50). However, a significant decrease in Hb (hemoglobin) rate and RBC (red blood cells) number in rats treated with higher doses of difenoconazole (1/38 and 1/9 of LD50) was obtained. Besides, difenoconazole treatment caused an increase in hepatic enzyme activities of alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH). Difenoconazole increased the levels of malondialdehyde (MDA) and advanced oxidation protein products (AOPPs), and decreased superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities and vitamin C levels in liver tissues compared to the control group. We also noted a degradation of nucleic acids, testifying difenoconazole genotoxicity. Changes in hepatic tissues were confirmed by histological findings. Co-administration of quercetin (20?mg/kg) improved hematological and biochemical parameters and showed a significant liver protective effect by decreasing MDA levels and producing advanced oxidation protein, along with increased antioxidative enzyme activities and vitamin C levels. Results were confirmed by the improvement of histological impairments. Thus, it appears that quercetin was effective in preventing acute liver injury induced by exposure to difenoconazole.     

Geraniol attenuates 2-acetylaminofluorene induced oxidative stress,inflammation and apoptosis in the liver of wistar rats

Abstract

2-Acetylaminofluorene (2-AAF), is a well-known liver toxicant, generally used to induce tumors in laboratory animals. Geraniol (GE), a monoterpene found in essential oils of herbs and fruits, has been known to possess preventive efficacy against chemically induced toxicities. The present study was designed to analyze the protective effect of GE against 2-AAF induced oxidative stress, inflammation, hyperproliferation and apoptotic tissue damage in the liver of female Wistar rats. 2-AAF (0.02% w/w in diet) was administered and subjected to partial hepatectomy, as a mitogenic stimulus for the induction of hyperproliferation of liver tissue. GE was pre-treated orally at two different doses (100 and 200?mg/kg b.wt.) dissolved in corn oil. GE pre-treatment significantly ameliorated 2-AAF induced oxidative damage by diminishing tissue lipid peroxidation accompanied by the increase in enzymatic activities of catalase, glutathione peroxidase, glutathione reductase, superoxide dismutase and reduced glutathione content. The level of serum toxicity markers (AST, ALT, LDH) was found to be decreased. Pre-treatment with GE downregulated the expression of caspase-3,9, COX-2, NFkB, PCNA, iNOS, VEGF and significantly decreased disintegration of DNA. Histological findings further revealed that GE significantly restores the architecture of liver tissue. In the light of the above observations it may be concluded that GE may be used as preventive agent against 2-AAF induced oxidative stress, inflammation, hyperproliferation and apoptotic damage.     

Acrolein-induced oxidative stress and genotoxicity in rats: protective effects of whey protein and conjugated linoleic acid

Acrolein (AC), a highly reactive hazardous pollutant, poses serious threats to human health. Whey protein (WP) and conjugated linoleic acid (CLA) have beneficial health implications. We investigated the protective effects of WP and CLA against AC-induced toxicity in rats. The animals were orally gavaged with CLA (200?mg/kg/day), WP (200?mg/kg/day), AC (5?mg/kg/day), CLA?+?AC (200?+?5?mg/kg/day), and WP?+?AC (200?+?5?mg/kg/day) six days per week for 30?days. The oral administration of AC significantly induced oxidative stress by increasing thiobarbituric acid reactive substances (TBARS) and protein carbonyls (PCOs) levels and decreasing glutathione (GSH) level in the spleen, thymus, and polymorphonuclear leukocytes (PMNs). It also increased the frequencies of micronucleus (MN) and megakaryocytic emperipolesis (ME) and decreased the ratio of polychromatic erythrocytes (PCEs) in bone marrow. Slight alterations in urinary 8-hydroxydeoxyguanosine (8-OHdG) levels were not significant. Co-treatment with CLA?+?AC or WP?+?AC ameliorated the values of oxidative stress, MN, PCE, and ME. These data suggest that CLA and WP can improve the antioxidant defenses and preclude the formation of genetic damage and ME.     

Sildenafil attenuates oxidative stress and endothelial dysfunction in lead-induced hypertension

Lead (Pb) reduces NO bioavailability, impairs the antioxidant system, and increases the generation of reactive oxygen species (ROS). Pb-induced oxidative stress may be responsible for the associated endothelial dysfunction. Sildenafil has shown nitric oxide (NO)-independent action, including antioxidant effects. Therefore, we examined the effects of sildenafil on oxidative stress, reductions of NO and endothelial dysfunction in Pb-induced hypertension. Wistar rats were distributed into three groups: Pb, Pb + sildenafil and Sham. Blood pressure and endothelium-dependent vascular function were recorded. We also examined biochemical determinants of lipid peroxidation and antioxidant function. ROS levels, NO metabolites and NO levels in human umbilical vein endothelial cells (HUVECs) were also evaluated. Sildenafil prevents impairment of endothelium-dependent NO-mediated vasodilation and attenuates Pb-induced hypertension, reduces ROS formation, enhances superoxide dismutase (SOD) activity and antioxidant capacity in plasma and increases NO metabolites in plasma and HUVECs culture supernatants, while no changes were found on measurement of NO released from HUVECs incubated with plasma of the Pb and Pb + sildenafil groups compared with the sham group. In conclusion, sildenafil protects against ROS-mediated inactivation of NO, thus preventing endothelial dysfunction and attenuating Pb-induced hypertension, possibly through antioxidant effects.