Liver GPx Research Articles

Effect of phosphorus supplementation on cell viability, anti-oxidative capacity and comparative proteomic profiles of puffer fish (Takifugu obscurus) under low temperature stress

The aim of this study was to investigate the effects of dietary phosphorus (P) on the growth and response of obscure puffer under low temperature stress. Six diets were supplemented with graded levels (0, 0.2, 0.4, 0.6, 0.8, 1.2%) of P from Monocalcium phosphate. The analyzed total P contents of the six diets were 0.40, 0.60, 0.81, 0.98, 1.19 and 1.55% respectively. The results showed fish fed diets supplemented with 0 and 0.2% P had significantly lower weight gain, feed efficiency and feed intake than fish fed diets supplemented with 0.6, 0.8 and 1.2% P. After the 8-week feeding trial, puffer fish were exposed to acute low temperature challenge (12±2°C) and sampled at different time points (0, 3, 6, 12, 24, 48h). The blood cell numbers were significantly higher in fish fed diets supplemented with 0.6, 0.8 and 1.2% P than in fish fed diets without P supplement at 6, 12, 24 and 48h. The highest rate of viable blood cells was observed in fish fed diets supplemented with 0.6 or 0.8% P at 3 and 6h. At 6, 24 and 48h, the respiratory burst activities tended to decrease with increasing dietary P supplement up to 0.6, 1.2 or 0.8%, respectively. At 12, 24 and 48h, plasma CAT activity increased with increasing dietary P supplement up to 0.8%. The highest plasma SOD activity was in fish fed diets supplemented with 0.6 and 0.8% P at 6h. At 3, 6, 12, 24 and 48h, liver GPx activity increased significantly with the increase of dietary P supplement, and GPx activity in the 0.8% feed group achieved the highest. Fish fed diet without P supplement showed the highest plasma MDA level at 3h and 6h, highest liver MDA level at 12h and 24h. Two-dimensional electrophoresis proteomic approach was used to investigate altered proteins between P deficient (P=0) and adequate (P=0.8%) group in liver of puffer fish during cold stress treatment. MALDI-TOF/TOF MS analysis revealed that adequate P diet significantly up-regulated three energy generation related enzymes (ribose-5-phosphate isomerase-like 5, ribulose-phosphate 3-epimerase-like and alpha-enolase-like isoform 2) and two lipid transport proteins (ApoA-I and FABP), and down-regulated an intermediate filament protein (keratin type I cytoskeletal 13-like) of puffer fish during cold stress. These results clearly indicated that dietary P supplement could improve cell viability, anti-oxidative capacity, energy generation and lipid transportation of puffer fish under cold stress. Statement of relevanceThis study indicates that dietary P improved cell viability, anti-oxidative capacity, energy generation and lipid transportation of puffer fish under cold stress. The results will contribute to our understanding of the role of phosphorus metabolism in aquatic animals.

Cloning, Sequencing, and Expression of Selenoprotein Transcripts in the Turkey (Meleagris gallopavo).

The minimum Se requirement for male turkey poults is 0.3 μg Se/g – three times higher than requirements found in rodents – based on liver and gizzard glutathione peroxidase-4 (GPX4) and GPX1 activities. In addition, turkey liver GPX4 activity is 10-fold higher and GPX1 activity is 10-fold lower than in rats, and both GPX1 and GPX4 mRNA levels are dramatically down-regulated by Se deficiency. Currently, the sequences of all annotated turkey selenoprotein transcripts and proteins in the NCBI database are only “predicted.” Thus we initiated cloning and sequencing of the full turkey selenoprotein transcriptome to demonstrate expression of selenoprotein transcripts in the turkey, and to develop tools to investigate Se regulation of the full selenoproteome. Total RNA was isolated from six tissues of Se-adequate adult tom turkeys, and used to prepare reverse-transcription cDNA libraries. PCR primers were designed, based initially on chicken, rodent, porcine, bovine and human sequences and later on turkey shotgun cloning sequences. We report here the cloning of full transcript sequences for 9 selenoproteins, and 3'UTR portions for 15 additional selenoproteins, which include SECIS elements in 22 3'UTRs, and in-frame Sec (UGA) codons within coding regions of 19 selenoproteins, including 12 Sec codons in SEPP1. In addition, we sequenced the gap between two contigs from the shotgun cloning of the turkey genome, and found the missing sequence for the turkey Sec-tRNA. RTPCR was used to determine the relative transcript expression in 6 tissues. GPX3 expression was high in all tissues except kidney, GPX1 expression was high in kidney, SEPW1 expression was high in heart, gizzard and muscle, and SELU expression was high in liver. SEPP2, a selenoprotein not found in mammals, was highly expressed in liver but not in other tissues. In summary, transcripts for 24 selenoproteins are expressed in the turkey, not just predicted.

Selenium Status Biomarkers and Selenium Requirements in the Turkey (M. gallopavo)

Glutathione peroxidase (Gpx) activity has been used extensively to determine selenium (Se) status and requirements. The identification of the full selenoproteome and the use of transcriptomics offer additional biomarkers for assessment of Se status. We recently reported the Se requirement for the turkey based on Gpx1 and Gpx4 activity was 0.3 mg Se/g diet (vs. 0.2 mg/g NRC 1994), and that both Gpx mRNAs were reduced by Se deficiency (Exp Biol Mol 235:23). To determine Se status in today's rapidly growing commercial turkeys using both traditional and mRNA biomarkers, we fed day‐old male poults (n=50) a Se‐deficient diet (0.005 mg/g) supplemented with 10 graded levels of Se (0‐1.0 mg/g) for 28 d. There was no significant effect of Se on growth, although deficient (–Se) poults averaged 533±134 g vs. 769±202 g in 0.4 mg/g poults. Se response curves and plateau breakpoints (BP) were used to determine the impact of deficiency and minimal Se requirements. Plasma Gpx3 activity (n=5/trt) in –Se poults fell to <2% of Se‐adequate levels (+Se), showing our birds were Se deficient. The BP for plasma Gpx3 activity was 0.22 mg/g. Gpx1 in red blood cells fell to 34% of +Se and reached a BP at 0.25 mg/g. Initial analysis (n=3/trt) showed liver Gpx1 and Gpx4 activity in –Se poults fell to 4 and 6% of +Se, respectively, and reached BP at 0.28 and 0.14 mg/g, respectively. qRT‐PCR of total RNA (n=3/trt) showed –Se liver Gpx1 and Gpx4 mRNA levels fell to 32 and 17%, respectively, of +Se, with both BPs at 0.05 mg/g. Turkey Se requirements based on Gpx activity are ~3x higher than in rats but Gpx1 mRNA‐based requirements are the same as in rats. This study shows Gpx4 liver mRNA and activity are highly regulated by Se status in turkeys, in contrast to rodents, and that the turkey minimal Se requirement is 0.3 mg Se/g. Support: WIS 1829 and UW Se Nutrition Research Fund

Estimation of dietary selenium requirement for Chinese egg-laying ducks

The purpose of this study was to estimate the selenium (Se) requirement of egg-laying ducks based on daily egg production and the selenoprotein glutathione peroxidase (Gpx). Five-hundred and forty laying ducks were divided into six treatments, each containing six replicates of 15 ducks. The birds were caged individually and received a Se-deficient basal diet (0.04 mg/kg) or diets supplemented with 0.08, 0.16, 0.24, 0.32, 0.40 mg/kg Se (as sodium selenite) for 6 months. The experiment consisted of two periods: an early-laying period of 2 months and the peak-laying period of 4 months. Egg production and feed intake were recorded daily. At the end of the experiment, blood samples were drawn for determination of Gpx activity in plasma (Gpx3) and in erythrocytes (Gpx1). Hepatic Gpx1 activity and relative expression of Gpx1 mRNA were also determined. Eggs (n = 6) were sampled for quality determination and Se content at the end of the experiment. The activities of plasma Gpx3, erythrocyte Gpx1 and liver Gpx1 increased in a quadratic manner (P < 0.001) with increasing supplemental Se. The mRNA abundance of hepatic Gpx1 increased linearly (P < 0.001) with dietary Se supplementation. Egg shell thickness was significantly reduced in the ducks fed 0.44 mg Se/kg (P < 0.05), indicating that higher dietary Se tends to compromise egg shell quality. Yolk and albumen contents of Se increased linearly (P < 0.0001) with dietary Se supplementation. Using quadratic broken line models, the Se requirement for daily egg production was 0.18 mg/kg for early-laying ducks and 0.24 mg/kg for peak-laying ducks; for optimal function of Gpx (peak-laying ducks), it was 0.37 mg Se/kg.

Effects of Xuefu Zhuyu decoction on antioxidant and drug-metabolizing enzymes in liver of rats

Xuefu Zhuyu decoction (XFZYD) is a famous traditional Chinese medicine (TCM) formula, is widely used in the treatment of cardiovascular and cerebrovascular diseases in China over one hundred years. But its effect on antioxidant and drug-metabolizing enzymes are unknown. This study was to observe the effects of Xuefu Zhuyu decoction (XFZYD) on the activities of antioxidant and drug metabolism enzymes (DMEs) in liver of rats. Male SD rats, treated with XFZYD at the dosage of 3.51, 7.02 and 14.04 g x kg(-1) per day for 15 days, serum were collected, tissue fluid, cytosols and microsomes isolated from liver tissues were prepared by centrifugation according to the standard procedure, the activities of antioxidant enzymes and drug-Metabolizing Enzymes were determined by UV-V is spectrophotometer. In serum, the activities of AST was not significantly affected by the treatment with XFZYD, at the high- est dose, the levels of ALT, Cr and BUN were significantly decreased (P < 0.05). GPX were significantly increased at the dose of 7.02, 14.04 g x kg(-1) (P < 0.05), CAT were significantly increased at the highest dose (P < 0.05). T-SOD was not significantly af- fected by this treatment. In the liver tissue, GPX was significantly increased at the dose of 3.51, 7.02 g x kg(-1) (P < 0.05), GST, CAT and T-SOD were not significantly affected following this treatment. In cytosols, GST was significantly increased at the dose of 3.51 g x kg(-1) (P < 0.05), T-SOD was remarkable induced at the dose of 3.51 and 7.02 g x kg(-1) (P < 0.05). In microsomes, XFZYD had no significant effect on Cytochromeb5, NADPH-Cytochrome P450 reductase, CYP3A, CYP2E1 and UGT, XFZYD significantly in- duced GST at the dose of 3.51 and 7.02 g x kg(-1) (P < 0.05), and the level of GSH were significantly increased by XFZYD at the dose of 3.51, 7.02 and 14.04 g kg(-1) (P < 0.05). These findings suggest XFZYD can induce the activities of GPX, CAT, SOD, GST and increase GSH level in liver of rats, which indicate XFZYD may have detoxification and antioxidant functions.

A new isoflavonoid from seeds of Lepidium sativum L. and its protective effect on hepatotoxicity induced by paracetamol in male rats.

A new isoflavonoid, 5,6-dimethoxy-2',3'-methylenedioxy-7-C-β-d-gluco-pyranosyl isoflavone was isolated from the seeds of Lepidium sativum L. along with two known isoflavonoids, 7-hydroxy-4',5,6-trimethoxyisoflavone and 7-hydroxy-5,6-dimethoxy-2',3'-methylenedioxyisoflavone. The structures of all compounds were elucidated with NMR spectrometry. Compounds 1, 2 and the new isoflavonoid 3 were evaluated for their ability to reduce the hepatotoxicity induced by paracetamol in male rats by reducing the damage and toxicity effects on liver cells with a significant improvement of total antioxidant capacity, normalizing the levels of liver enzymes GSH, SOD, GPX, CAT and GST compared to control group.

Evaluation of Antioxidant and Hepatoprotective Activities of Moringa oleifera Lam. Leaves in Carbon Tetrachloride-Intoxicated Rats.

The antioxidant and hepatoprotective activities of the extract of Moringa oleifera leaves were investigated against CCl4-induced hepatotoxicity in rats. Hepatotoxic rats were treated with ethanol extract of Moringa oleifera for a period of 60 days at the following three dose levels; 100, 200 and 400 mg/kg body weight/day, orally. The activities were studied by assaying the serum marker enzymes like SGOT, SGPT, GGT, LDH, ALP, ACP, as well as total bilirubin, total protein and albumin in serum concomitantly with the activities of LPO, SOD, CAT, GSH, GR and GPx in liver. The activities of all parameters registered a significant (p ≤ 0.001) alteration in CCl4 treated rats, which were significantly recovered towards an almost normal level in rats co-administered with M. oleifera extract in a dose-dependent manner. All the biochemical investigations were confirmed by the histopathological observations and compared with the standard drug. silymarin. Results suggest that the antioxidant and hepatoprotective activities of M. oleifera leaves are possibly related to the free radical scavenging activity which might be due to the presence of total phenolics and flavonoids in the extract and/or the purified compounds β-sitosterol, quercetin and kaempferol, which were isolated from the ethanol extract of M. oleifera leaves.

Effects of Polysaccharides from &lt;i&gt;Radix astragali&lt;/i&gt; on Oxidative Stress Induced by Exhaustive Swimming Exercise in Liver and Muscle of Mice

Polysaccharides, the mainly bioactive ingredient ofRadix Astragali, were evaluated for its effects on the oxidative stress induced by exhaustive swimming exercise of mice. A total of 48 mice were randomly divided into four groups: control group, low-dose polysaccharide fromAstragali radix(RAP) treated group, medium-dose RAP treated group, and high-dose RAP treated group. The control group received only distilled water ig, and the RAP treated groups received different doses of RAP (50, 100, and 200 mg/kg, ig) for 28 days. After the final treatment with RAP, the mice were subjected to swimming to exhaustion and the superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were measured. The data showed that RAP promote increases in the activities of SOD, GPX and CAT in liver and muscle of mice, and the high-dose RAP (200 mg/kg) presented the best effect. These results indicated that RAP possessed protective effects against exercise-induced oxidative stress.

Effects of short term exposure of atrazine on the liver and kidney of normal and diabetic rats.

The present study evaluates the effects of short term (15 days) exposure of low dose (300 μg kg−1) of atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) on antioxidant status and markers of liver and kidney damage in normal (nondiabetic) and diabetic male Wistar rats. Rats were divided into four groups: Group I as normal control, Group II as atrazine treated, Group III as diabetic control, and Group IV as atrazine treated diabetic rats. Atrazine administration resulted in increased MDA concentration as well as increased activities of SOD, CAT, and GPx in both liver and kidney of atrazine treated and atrazine treated diabetic rats. However, GSH level was decreased in both liver and kidney of atrazine treated and atrazine treated diabetic rats. Atrazine administration led to significant increase in liver damage biomarkers such as AST, ALT, and ALP as well as kidney damage biomarkers such as creatinine and urea in both normal and diabetic rats, but this increase was more pronounced in diabetic rats when compared to normal rats. In conclusion, the results of the present study demonstrate that short term exposure of atrazine at a dose of 300 μg kg−1 could potentially induce oxidative damage in liver and kidney of both normal and diabetic rats.

Can Recombinant Human Glutathione Peroxidase 1 with High Activity Be Efficiently Produced inEscherichia coli?

Cellular glutathione peroxidase 1 (GPx1) is an important antioxidant selenoenzyme. Due to the presence of selenocysteine (Sec) encoded by UGA, normally recognized as a stop codon, the expression of mammalian GPx with traditional recombinant DNA technology is extremely difficult. In this study, a series of human GPx1 (hGPx1) mutants with significantly high catalytic activities were produced for the first time in an Escherichia coli BL21(DE3)cys auxotrophic strain using the single-protein production system. Cys residues in hGPx1 were mutated to Ser in turn because untargeted substitution of Sec in place of Cys resulted in the decline of recombinant selenoenzyme activity. The results of this work showed that the catalytic activities of the mutants increased progressively with decreasing number of noncatalytic Sec residues. Seleno-hGPx1-C2/78/115/156/202S with all Cys residues changed to Ser showed the highest activity (21,268 U/μmol), which was more than 10-fold higher than bovine liver GPx. This increase could be explained by structural analysis of hGPx1 mutants based on homology modeling and binding site analysis. These results lead to the hypothesis that the conversion of noncatalytic Sec residues to Ser may optimize the structure of seleno-GPx in this expression system and consequently increase the catalytic efficiency.

‘Ashvagandharishta’ prepared using yeast consortium from Woodfordia fruticosa flowers exhibit hepatoprotective effect on CCl4 induced liver damage in Wistar rats

Ethanopharmacological relevanceConsortium of yeasts sourced from traditionally used Woodfordia fruticosa flowers proved to be beneficial for fermenting Ashvagandharishta. It resulted in faster fermentation, acceptable organoleptic properties and demonstrable hepatoprotective potential in CCl4 induced hepatotoxicity. To formulate Ashvagandharishta using consortium of yeasts and to investigate its physiochemical parameters. Standardize the formulation with the help of standard withaferin-A and withanolide-A and to evaluate its hepatoprotective potential in CCl4 induced hepatotoxicity in the rat model. Material and methodsAshvagandharishta was prepared using a 5% consortium of yeasts and ascertained its quality through physiochemical and phytochemical investigation. Withaferin-A and withanolide-A was simultaneously estimated by HPLC for standardization. Hepatoprotective potential was evaluated by administering 2.31 and 1.15ml/kg doses while considering biochemical parameters like serum AST, ALT, ALP and lipid profile. Gene expression study was carried out for the expression of antioxidant and inflammatory genes such as CAT, GPx and proinflammatory gene IL-6. Histopathology of liver was also studied with the help of H&E staining. ResultsAshvagandharishta was found organolepticaly acceptable with optimized physiochemical parameters. Withaferin-A and withanolide-A in Ashvagandharishta estimated as 0.3711, 0.7426 (%w/v), respectively. In the CCl4 induced hepato-toxicity model, Ashvagandharishta-2.31ml/kg dose showed significant decrease in elevated hepatic level of AST(p<0.001), ALT(p<0.01) and ALP(p<0.001). Both doses of Ashvagandharishta showed significant reduction of TG, Cholesterol, VLDL and LDL in serum, with corresponding reduction of (p<0.001) serum-HDL. Ashvagandharishta also showed increased serum protein (p<0.05) and albumin (p<0.01) with decrease in bilirubin (p<0.01). Additionally, Ashvagandharishta administration revealed up-regulation in antioxidant genes such as CAT and GPx in liver with concomitant down-regulation in proinflammatory IL-6gene (p<0.01). Histopathological parameters revealed restoration of normal tissue architecture by both doses of Ashvagandharishta. ConclusionsConsortium of yeasts from Woodfordia fruticosa flowers showed better fermentation pattern for Ashvagandharishta produced with acceptable organoleptic properties. Hepatoprotection shown by Ashvagandharishta was mainly through prevention of oxidative damage. Up-regulation of CAT and GPx genes and corresponding down regulation of proinflammatory IL6 gene was revealed as possible mechanism of its action.

English

The aim of study is to detect the effects and relevant mechanisms of oxysophoridine on alcoholic hepatic injury in mice. Sixty male Institute of Cancer Research (ICR) mice were randomly divided into a normal control group, an alcoholic liver injury model group, a positive control (tiopronin) group and an oxysophoridine (250, 125, 62.5 mg/kg) group. Consecutive interventions were conducted on each group for 10 days; specimens were obtained according to requirements of the testing indicators 16 h after the last drug administration. The protective effects were evaluated by biochemical parameters including serum aspartate transaminase (AST), alanine transferase (ALT), reduced glutathione (GPx), liver malondialdehyde (MDA) and superoxide dismutase (SOD). The pathological changes of the liver in microstructure and ultrastructure were observed. A decreased level of serum ALT, AST activity and liver MDA content with increased liver SOD, GPx activity (P&lt;0.05) were observed (P&lt;0.05) in the oxysophoridine group compared with the alcoholic liver injury model group, in which elevated serum ALT and AST activity were recorded, along with a marked increase of liver MDA (P&lt;0.05), decrease of liver SOD and GPx (P&lt;0.05). The following changes of the liver were observed in the model group: Blurred contour of the hepatic lobule with punctated or focal necrosis in partial liver cells, multiple intracellular microvesicular steatosis, with lipid droplets formed in the cytoplasm, marked swelling of hepatocytes and disarrangement of hepatic cords, swelling of mitochondria, with disappeared or broken cristae, enlarged endoplasmic reticulum and condensed chromatin. Compared with the model group, a decrease in pathological changes of various degrees was observed in the oxysophoridine group at various doses. The result indicates that oxysophoridine prevents alcoholic liver damage in mice and the protective effect may be associated with anti-oxidative stress. &nbsp; Key words:&nbsp;&nbsp;Alcohol, oxysophoridine, oxidative stress, antioxidants.

Synthesis, anti-inflammatory, and structure antioxidant activity relationship of novel 4-quinazoline

The practice of medicinal chemistry is devoted to the discovery and development of new agents for treating disease. A new derivative of methyl 2-((E)-3-(3,4-dihydroxyphenyl)acrylamido)benzoate 2 was synthesized by reacting the amino group of methyl anthranilate 1 with caffeic acid in the presence of PCl3. Cyclcondensation of 2 with hydrazine hydrate afforded the corresponding 2,3-dihydro-2-(3,4-dihydroxyphenyl) pyrazolo[5,1-b]quinazolin-9(1H)-one 3. The median lethal doses (LD50s) of compounds 2 and 3 in mice were 1,135 and 495 mg/kg b.w., respectively. The anti-inflammatory, reducing power, chelating activity on Fe2+, free radical-scavenging, and total antioxidant activities were more pronounced in compound 2 compared to compound 3. On the other hand, antipyretic activity was more pronounced in compound 3 compared to compound 2. Antioxidant activity of compounds 2 and 3 increased with increased concentrations. Total antioxidant activity of compounds 2, 3 and both standards decreased in the order of α-tocopherol > compound 2 > trolox > BHA > BHT > compound 3. Administration of compounds 2 and 3 orally to the rats at dose of 50, 100, and 150 mg/kg b.w., for 10 days showed non-significant changes in serum level of GOT, GPT, ALP, γ-GT, and LDH as compared with the control group. In addition, oral administration of the compound 2 at a concentration of 100 and 150 mg/kg b.w. and compound 3 at a concentration of 150 mg/kg b.w. daily to normal rats for 10 days showed a significant increase in liver GSH, GPx, GR, and GST activities and significant decrease in TBARS level. But, administration of diclofenac sodium (30 mg/kg b.w.) orally to the rats daily for 10 days to rats showed significant increase in serum SGOT, SGPT, ALP, γ-GT, and LDH and significant decrease in liver GSH, GPx, GR, and GST activities. These findings suggest that compounds 2 and 3 exhibited good antioxidant and anti-inflammatory activity and also showed effects on liver enzymes.

Cloning, sequencing, and expression of a subset of selenoprotein transcripts in the turkey (Meleagris gallopavo)

We recently reported that the minimum Se requirement for male turkey poults is 0.3 μg Se/g – three times higher than requirements found in rodent – based on liver and gizzard Gpx4 and Gpx1 activities (Exp Biol Med 235:23 (2010)). We also found that levels and Se regulation of Gpx4 activity and mRNA in turkeys are distinct from those in mammals. Thus we initiated cloning of turkey selenoprotein transcripts as a preliminary step to investigate Se regulation of the full selenoproteome. Using homology of mammalian and G. gallus (chicken) transcripts and proteins, primers for qRT‐PCR were designed to examine the relative expression of selenoproteins in total RNA isolated from 6 turkey tissues (liver, heart, kidney, gizzard, thigh, breast) of an adult male Nicholas‐strain (white) turkey. Fold‐changes in different tissues relative to liver were: for kidney, Gpx1 11X, Txnrd1 4X, Sepn1 3X, Sepw1 3X; for heart, Sepw1 6X, Sepn1 4X, Dio2 4X; for gizzard, Sepn1 6X, Selm 3X, Sepw1 2X; for breast, Sepw1 6X; for thigh, Sepw1 4X, Dio2 3X, Sepn1 2X. 3ˈ‐RACE was used to clone and sequence 17 selenoproteins, including 5 selenoproteins (Gpx3, Sepp1, Sepp2, Sepw1, Sep15) currently not predicted by the 2010 next‐generation sequencing of the turkey genome (PloS Biology 8:e1000475 (2010)). These sequences will be used to develop molecular biomarkers to characterize Se regulation in the turkey. (UW Hatch WI04909 and Selenium Nutrition Research Fund)

Effect of selenium sources on the expression of cellular glutathione peroxidase and cytoplasmic thioredoxin reductase in the liver and kidney of broiler breeders and their offspring

In total, 180 Lingnan Yellow broiler breeders were used to investigate the effect of different sources of selenium (Se) on the expression of cellular glutathione peroxidase (GPx1) and cytoplasmic thioredoxin reductase (TrxR1) in the liver and kidney of broiler breeders and their offspring by quantitative real-time PCR. There were 6 replicates of 3 dietary treatments. Broiler breeders were fed corn-soy-based diets supplemented with 0.15 mg/kg of Se from sodium selenite, Se-enriched yeast (SY), or selenomethionine (SM). At the end of the feeding trial, liver and kidney mRNA levels of GPx1 and TrxR1 were determined by quantitative real-time PCR, as well as the activity of GPx1 and TrxR1 in liver and kidney of breeders and their offspring. The results showed that, compared with sodium selenite, SY or SM significantly increased (P < 0.05) the activity of TrxR1 in the liver and kidney of broiler breeders and their offspring but not the GPx1 activity. The liver GPx1 and TrxR1 mRNA levels in SY or SM groups were higher (P < 0.05) than that in the sodium selenite group. And the kidney TrxR1 mRNA levels were also significantly increased (P < 0.05) by using SY or SM, whereas there was no significant difference in the kidney GPx1 mRNA levels between the organic or inorganic sources of Se used.

Acute exposure of moniliformin increases the 8-OHdG levels in SD-rat urine

groups treated with estradiol or -lipoic acid or l-carnitine alone or in combination with CCl4. The results of the study: The results showed that treatment with CCl4 induced significant changes in serum biochemical parameters, the histological and histochemical pictures of the liver accompanied by a significant increase in MDA and a significant decrease in SOD and GPx in liver. Whereas, animals treated with estradiol or -lipoic acid or l-carnitine were comparable to the control. On the other hand, estradiol or -lipoic acid or l-carnitine could improve the biochemical parameters, decreased the oxidative stress and improved the histological and histochemical pictures in the liver of CCl4-treated rats. It could be concluded that estradiol,-lipoic acid and l-carnitine succeeded to ameliorate the oxidative stress on liver. This improvement was pronounced in the group treated with -lipoic more than l-carnitine and the least in group treated with estradiol.

Synthesis of some novel triazoloquinazolines and triazinoquinazolines and their evaluation for anti-inflammatory activity

A series of triazoloquinazolines and triazinoquinazolines were synthesized as novel anti-inflammatory agents. Some of the newly synthesized compounds 8, 11, and 19 showed good anti-inflammatory activities. Also, the median lethal doses (LD50s) of compounds 8, 11, and 19 in mice were 222.25, 213.25, and 235 mg/100 g b.w., respectively. Oral administration of compounds 8, 11, and 19 to the rats at dose of 300 mg/kg b.w. for 10 days showed non-significant changes in liver enzymes SGOT, SGPT, ALP, LDH, γ-GT, SOD, GPx, and blood GSH and serum TBARs as compared with the control group. But, administration of indomethacin orally to the rats at a concentration of 600 mg/kg b.w. daily for 10 days to rats showed significant increase in serum SGOT, SGPT, ALP, LDH, γ-GT, and TBARs and significant decrease in blood GSH, SOD, and GPx. These findings suggest that compounds 8, 11, and 19 exhibited good anti-inflammatory activity and more safe on liver enzymes in rats.

In vitro and in vivo antioxidant activity of Symplocos cochinchinensis S. Moore leaves containing phenolic compounds

Methanol extract of Symplocos cochinchinensis S. Moore leaves was evaluated for its in vitro and in vivo antioxidant activity. The total phenolic content of the extract was 230mg of gallic acid equivalents/g extract. The extract showed very good scavenging activity on 2,2-diphenyl-picrylhydrazyl (DPPH) (IC50 620.30±0.14μg/ml), hydroxyl (IC50 730.21±1.05μg/ml), nitric oxide (IC50 870.31±0.19μg/ml) radicals, as well as high reducing power. The extract also showed strong suppressive effect on lipid peroxidation. In in vivo study CCl4 induced oxidative stress produced significant increase in SGOT, SGPT and LDH levels along with reduction in liver SOD, CAT, GSH and GPx levels. Pre-treatment of rats with the extract (250 and 500mg/kg) for 7days showed significant reduction in the levels of SGOT, SGPT and LDH compared to CCl4 treated rats. SOD, CAT, GSH and GPx levels were increased significantly due to treatment with the extract. The activity of the extract was comparable to the standard drug, silymarin (25mg/kg). The results suggest that the leaves of S. cochinchinensis are a source of natural antioxidants.

Antioxidant and antiapoptotic effects of green tea polyphenols against azathioprine-induced liver injury in rats

Green tea polyphenols (GTP) is considered to have protective effects against several diseases. The hepatotoxicity of azathioprine (AZA) has been reported and was found to be associated with oxidative damage. This study was conducted to evaluate the role of GTP to protect against AZA-induced liver injury in rats. AZA was administered i.p. in a single dose (50 mg kg −1) to adult male rats. AZA-intoxicated rats were orally administered GTP (either 100 mg kg −1 day −1 or 300 mg kg −1 day −1, for 21 consecutive days, started 7 days prior AZA injection). AZA administration to rats resulted in significant elevation of serum transaminases (sALT and sAST), alkaline phosphatase (sALP), depletion of hepatic reduced glutathione (GSH), catalase (CAT) and glutathione peroxidase (GPx), accumulation of oxidized glutathione (GSSG), elevation of lipid peroxides (LPO) expressed as malondialdehyde (MDA), reduction of the hepatic total antioxidant activity (TAA), decrease serum total proteins and elevation of liver protein carbonyl content. Significant rises in liver tumor necrosis factor-alpha (TNF-α) and caspase-3 levels were noticed in AZA-intoxicated rats. Treatment of the AZA-intoxicated rats with GTP significantly prevented the elevations of sALT, sAST and sALP, inhibited depletion of hepatic GSH, GPx, CAT and GSSG and inhibited MDA accumulation. Furthermore, GTP had normalized serum total proteins and hepatic TAA, CAT, TNF-α and caspase-3 levels of AZA-intoxicated rats. In addition, GTP prevented the AZA-induced apoptosis and liver injury as indicated by the liver histopathological analysis. The linear regression analysis showed significant correlation in either AZA-GTP100 or AZA-GTP300 groups between TNF-α and each of serum ALT, AST, ALP and total proteins and liver TAA, GPX, CAT, GSH, GSSG, MDA and caspase-3 levels. However, liver TNF-α produced non-significant correlation with the serum total proteins in both AZA-GTP100 and AZA-GTP300 groups. In conclusion, our data indicate that GTP protects against AZA-induced liver injury in rats through antioxidant, anti-inflammatory and antiapoptotic mechanisms. However, further merit investigations are needed to verify these results and to assess the efficacy of GTP therapy to counteract the liver injury and oxidative stress status.

Phospholipid hydroperoxide glutathione peroxidase (Gpx4) is highly regulated in male turkey poults and can be used to determine dietary selenium requirements

The dietary selenium recommendation for turkeys of 0.2 microg Se/g is higher than for many other species. Liver glutathione peroxidase-1 (Gpx1) activity levels determined using hydrogen peroxide (H(2)O(2)) in previous studies suggest that 0.2 microg Se/g may still be too low and that some of this Gpx1 activity might be due to phospholipid hydroperoxide Gpx (Gpx4). Thus we separated Gpx1 from Gpx4 by chromatography, demonstrated that 47% of the H(2)O(2) activity in Se-adequate turkey liver was due to Gpx4, and determined a factor for calculation of each activity. Day-old male poults were fed an Se-deficient torula diet (0.007 microg Se/g) supplemented with graded levels of Se (0-0.5 microg Se/g) for 27 days. Final body weights indicated a minimum Se requirement for growth of 0.05 microg Se/g. The liver had the highest Gpx4 activity in Se-adequate poults, and Gpx4 activity in Se-deficient liver decreased to 5% of Se-adequate levels, with an Se requirement of 0.29 microg Se/g. Liver Gpx1, gizzard Gpx1 and gizzard Gpx4 activities also had Se requirements of 0.28-0.30 microg Se/g, collectively yielding an Se requirement of 0.3 microg Se/g, which is three times higher than the requirements found in comparable rodent studies. We also sequenced partial cDNA clones for turkey Gpx1 (GQ502186) and Gpx4 (GQ502187), and found >60% identity with rodents and humans and >90% identity with chickens. Ribonuclease protection analysis showed that Gpx4 mRNA levels decrease substantially in Se-deficient turkey liver, unlike in rodents. These underlying differences in selenoprotein molecular biology may explain the elevated dietary Se requirements of turkeys.