Antioxidant Competence Research Articles

Overexpression of isochorismate synthase enhances drought tolerance in barley

Isochorismate synthase (ICS) is a key enzyme for the synthesis of salicylic acid (SA) in plants. SA mediates plant responses to both biotic and abiotic stresses. In previous studies, we found that overexpression of ICS (ICSOE) or suppression of ICS (ICSRNAi) affected the host response to Fusarium graminearum in barley. However, whether the barley ICS gene plays a role in adapting to abiotic stresses remains to be determined. In the present study, expression of the ICS gene was upregulated when treated with 20 % PEG6000, and ICSOE lines were more drought tolerant than wild type (WT) and ICSRNAi. In addition, the abscisic acid (ABA) levels in the ICSOE lines were higher than those in the WT and ICSRNAi lines under drought stress. High ABA levels significantly reduced Gs and E, which may impact water retention under drought stress. Under drought conditions, the activity of antioxidant enzymes was significantly higher in the ICSOE lines, correlating with a lower levels of reactive oxygen species (ROS) and malondialdehyde (MDA). Enhanced antioxidant competence also contributed to drought tolerance in ICSOE lines. These findings help elucidate the abiotic stress resistance of the ICS pathway in barley.

WITHDRAWN: The free radicals scavenging potential of methanol extract of seeds (Horse gram) of Macrotyloma uniflorum

Abstract The oxidants are the most responsible for aging and other life-threatening health issues such as cancer, compromised immune system, etc. The maintenance of free radicals in human physic is an essential factor to attain an extended lifespan. Hence, this research was designed to assess the antioxidant competence of methanolic extract of horse gram (Macrotyloma uniflorum) against various oxidants such as ferric complex, DPPH, hydroxyl, and phosphomolybdenum complex. Methanolic extract of horse gram possesses ferric reducing components. Hence it reduce the ferric and FRAP complex as up to 98% (each) with the concentration of 150 µg mL−1 with the IC50 value of 64.859 and 71.255 µg mL−1 respectively. Similarly, the DPPH and phosphomolybdenum complex radicals were effectively scavenged (93.14% and 95.42%) at the concentration of 150 µg mL−1 with the IC50 value of 150 59.7585 and 59.772 µg mL−1, respectively. Furthermore, these radicals scavenging activities were statistically significant at P

Effect of concomitant treatment of curcumin and melatonin on cisplatin-induced nephrotoxicity in rats

Cisplatin (CP) is a potent anticancer drug used to treat solid tumors. Its use, however, is dose-limited by its nephrotoxicity. We aimed to compare the effect of melatonin and curcumin given singly, with that of a combination of these two agents on CP-induced nephrotoxicity in rats. CP (6 mg/kg, given once intraperitoneally) induced nephrotoxicity as evidenced by several significant adverse physiological, biochemical and histopathological actions that included a reduction in body weight, increased urine production, and significant alterations in some conventional and novel renal damage indices in plasma, urine and kidneys. CP also elevated several pro-inflammatory cytokines and caused renal oxidative/nitrosative stress. Supplementation with either curcumin (200 mg/kg) or melatonin (10 mg /kg) given singly by oral gavage for eight consecutive days prior to CP injection and four days thereafter, significantly mitigated the adverse renal effects of CP, by attenuating the pro-inflammatory and apoptotic mediators and improving antioxidant competence in renal tissues of CP- treated rats. When curcumin and melatonin were given together, the ameliorative effect was augmented in some of the measured indices e.g. tumor necrosis factor alpha, cystatin C, uric acid, phosphorus in plasma and, urine creatinine and creatinine clearance. Renal platinum concertation was reduced more with curcumin than that with melatonin, while the reduction was maximized when both melatonin and curcumin were given. Pending further pharmacological and toxicological studies, a combination of these two agents is likely to be mor effective in mitigating the adverse renal effects of CP administered to cancer patients.

An Insight for Potent In-Vitro Antioxidant Status of Short-Chain Peptides

Peptides test drug 1, 2, 3 and 4 coded as RK, KH, RRH, and RRK were subjected to in-vitro antioxidant screening methods for the assessment of their potency using Ascorbic acid as the standard drug. Antioxidant screening in-vitro methods used are such as Superoxide radical scavenging activity, Reducing power method, Phosphomolybdenum method, Ferric thiocyanate method, Thiobarbituric acid method, β-Carotene linoleic acid method/conjugated diene assay, and Fenton's reagent method. Different concentrations of test drugs were made and antioxidant activity was calculated by estimating inhibition percentage and IC50 values which were consequently compared with standard drug. The entire test drug RK, KH, RRH, and RRK showed relatively better antioxidant competence with that of the standard drug. Based on the above estimations, KH and RRH could be considered as the best potent drug for the diverse formulations of antioxidant effect suitable for the avoidance of various human diseases.

Wheat F-box Protein TaFBA1 Positively Regulates Plant Drought Tolerance but Negatively Regulates Stomatal Closure.

The phytohormone abscisic acid (ABA) regulates plant growth and development, as well as responses to various stresses, such as salt and drought. The wheat TaFBA1 gene, which encodes an F-box protein, was previously identified in our laboratory by homologous cloning. We previously found that TaFBA1 expression was induced by ABA and drought stress. In this study, wild-type (WT), TaFBA1 over-expressing (OEs), TaFBA1 homologous gene mutants, and TaFBA1 recovery (Rs) Arabidopsis plants were used. We found that the germination rate, the cotyledon greening rate, the root length, and the photosynthetic performance of TaFBA1 OE plants were better than those of WT under drought and ABA conditions, but mutant plants showed the opposite trend, and overexpression of TaFBA1 in mutants can recover their phenotype. In addition, TaFBA1 was found to be a negative regulator of ABA-induced stoma movement; mRNA transcription of certain ABA signaling-related genes was lower in TaFBA1 OE plants than in WT plants following ABA treatment. Further, we found that TaFBA1 can interact with RCAR1 (an ABA receptor) and ABI5. BiFC assay showed that TaFBA1 may interact with RCAR1 in the plasma membrane. In addition, accumulation of ROS and MDA in TaFBA1 OE plants was lower than that in the WT plants after ABA and drought treatments. Based on these results, we suggest that TaFBA1-regulated ABA insensitivity may be dependent on regulating ABA-mediated gene expression through interacting with RCAR1 and ABI5. Increased antioxidant competence and decreased ROS accumulation may be an important mechanism that underlies improved drought tolerance in TaFBA1 OE plants.

Deterioration of Antioxidant Competence in Barley Lesion Mimic Mutant 194

A barley mutant, 194, was observed to exhibit leaf spot phenotype during the whole growing period. In the current research, the phenotype and antioxidant competence were studied in lesion mimic mutant 194. The plant height was slightly higher in mutant 194. In addition, the leaf spot per plant in mutant 194 was significantly higher than that in wild-type (WT). Antioxidant competence, as indicated by ROS accumulation, antioxidant enzymes activity, and the expression of antioxidant enzyme-encoding genes were also detected in mutant 194. Compared to the WT, mutant 194 displayed relatively higher accumulation of ROS and accompanied by lower activity of some antioxidant enzymes, and the down-regulation of antioxidant enzyme-encoding genes further demonstrated the deterioration of antioxidant competence in mutant 194. The results suggested that the lower antioxidant competence of mutant 194 could accumulate excessive ROS. The excessive ROS could induce PCD and has the potential in the disease resistant in mutant 194.

The role of dietary astaxanthin in European sea bass (Dicentrarchus labrax) growth, immunity, antioxidant competence and stress tolerance

The role of dietary astaxanthin in European sea bass (Dicentrarchus labrax) growth, immunity, antioxidant competence and stress tolerance

Biochemical Effect of Fisetinon Experimentally Induced Liver Damage in Rats

Fisetin (3, 7, 3′, 4′-TetrahydroxyFlavone) is a bioflavonoid found in fruits and vegetables. It displaysawidevariety of pharmacological properties, including antioxidant, anti-carcinogenic and anti-inflammatory effects. This study was done to explore the role of fisetin, in ameliorating oxidative damage in thioacetamide (TAA)-induced hepatic injury in rats. Thirty-six male albino rats were divided into three equal groups. Group I (normal control group): rats administered distilled water only. Group II (TAA-intoxicated group): rats received thioacetamide (50 mg/kg b. wt.) intraperitoneally twice weekly for 6 weeks. Group III (TAA + fisetinco-treated group): rats received thioacetamide (50 mg/kg b. wt.) and at the same time administered fisetin (10mg/kg b. wt./daily/orally) for 6 weeks (end of experiment). All animals were sacrificed after 6 weeks. The results revealed that serum levels of Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST), Alkaline Phosphatase (ALP) were significantly elevated in Group II. Oxidative stress in the group II was manifested by a significant rise inMalondialdehyde (L-MDA) levels with a marked reduction in Glutathione (GSH) content and diminished activity of antioxidant enzyme Glutathione-S-Transferase(GST), in liver tissues as compared with the control group. The coadministration of fisetin and thioacetamide (protection modality) restored the thioacetamide induced alterations in liver functions, promoted oxidative stress and antioxidant defense. Thus, the results of the present study indicate that fisetin treatment protects the hepatocytes by improving the antioxidant competence in hepatic tissues of thioacetamide intoxicated rats.

Reproductive sink enhanced drought induced senescence in wheat fertile line is associated with loss of antioxidant competence compared to its CMS line

Reproductive sinks regulate monocarpic senescence in wheat as desinking delayed flag leaf senescence under irrigated condition. In this study, wheat cv. HW 2041 and its isonuclear male sterile line (CMS) were subjected to post-anthesis water deficit stress to understand the association between sink strength, senescence and drought response in relation to oxidative stress and antioxidant defense at cellular and sub-cellular level. CMS plants maintained better water relations and exhibited delayed onset and progression of flag leaf senescence in terms of green leaf area, chlorophyll and protein content than fertile plants under water deficit stress (WDS). Delayed senescence in CMS plants under water deficit stress was associated with less reactive oxygen species generation, lower damage to membranes and better antioxidant defense both in terms of antioxidant enzyme activities and metabolite content compared to fertile plants. Expression of some senescence associated genes (SAGs) such as WRKY transcription factor (WRKY53), glutamine synthetase1 (GS1), wheat cysteine protease (WCP2) and wheat serine protease (WSP) was lower while catalse 2 (CAT2) transcript levels were higher in the CMS plants compared to HW2041 during senescence under water deficit stress. Antioxidant defense in chloroplasts was better in CMS line under water deficit stress compared to HW2041. This is the first report showing that reproductive sink enhanced drought induced senescence in flag leaf of wheat fertile line is associated with higher oxidative stress and damage and loss of antioxidant competence compared to its sterile line under water deficit stress. Higher expression of some SAGs and decline in superoxide dismutase and ascorbate peroxidase activity in the chloroplasts also contributed to the accelerated senescence in fertile line compared to its CMS line under WDS.

Quantitative and Discriminative Evaluation of Contents of Phenolic and Flavonoid and Antioxidant Competence for Chinese Honeys from Different Botanical Origins.

Phenolics and flavonoids in honey are considered as the main phytonutrients which not only act as natural antioxidants, but can also be used as floral markers for honey identification. In this study, the chemical profiles of phenolics and flavonoids, antioxidant competences including total phenolic content, DPPH and ABTS assays and discrimination using chemometric analysis of various Chinese monofloral honeys from six botanical origins (acacia, Vitex, linden, rapeseed, Astragalus and Codonopsis) were examined. A reproducible and sensitive ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was optimized and validated for the simultaneous determination of 38 phenolics, flavonoids and abscisic acid in honey. Formononetin, ononin, calycosin and calycosin-7-O-β-d-glucoside were identified and quantified in honeys for the first time. Principal component analysis (PCA) showed obvious differences among the honey samples in three-dimensional space accounting for 72.63% of the total variance. Hierarchical cluster analysis (HCA) also revealed that the botanical origins of honey samples correlated with their phenolic and flavonoid contents. Partial least squares-discriminant analysis (PLS-DA) classification was performed to derive a model with high prediction ability. Orthogonal partial least squares-discriminant analysis (OPLS-DA) model was employed to identify markers specific to a particular honey type. The results indicated that Chinese honeys contained various and discriminative phenolics and flavonoids, as well as antioxidant competence from different botanical origins, which was an alternative approach to honey identification and nutritional evaluation.

Integrated biomarkers response confirm the antioxidant role of diphenyl diselenide against atrazine

Atrazine (ATZ) is a herbicide worldwide used. That can cause oxidative damage in non-target organisms, such as fish. Furthermore, the threat of exposure to pesticides together with poor nutrition is hazardous to the normal development of fish, and supplementation of the fish diet with antioxidants compounds is an alternative approach to prevent the hazardous effects of pesticide exposure. Here we aimed to investigate the capacity of diphenyl diselenide (PhSe)2 diet supplementation to improve the antioxidant defense of Cyprinus carpio (carp) exposed to environmental concentrations of ATZ. To prove the efficiency of (PhSe)2, we used the Integrated Biomarkers Response (IBR) methodology. Therefore, carp were fed for 8 weeks diets either with or without (PhSe)2 and exposed to 2 or 10µg/L of ATZ for 96h, euthanized, and their liver, gills, and muscle tissues were removed for biochemical assays. ATZ was able to cause oxidative damage from reactive species production in all tissues of carp, as observed by the increase of lipid peroxidation and protein damage. The activity of some antioxidant enzymes was inhibited in carp exposed to ATZ. However, (PhSe)2 supplementation was able to prevent this ATZ-induced damage by improving the activities of antioxidant enzymes and through antioxidant competence of (PhSe)2per se. Furthermore, IBR was shown to be a useful tool to compare treatments, even at different concentrations, and identify the efficiently antioxidant behavior of the organoselenium compound

Improved salt tolerance in a wheat stay-green mutant tasg1

Salt stress inhibited the growth of both tasg1 and wild-type (WT) wheat seedlings, but the inhibition in tasg1 plants was relatively weaker than that of WT. Compared to the WT, the chlorophyll content, thylakoid membrane polypeptides, Hill reaction activity, actual photochemical efficiency of PSII (ΦPSII), and Mg2+- and Ca2+-ATPase activities were higher in tasg1 under salt stress. At the same time, the photosynthetic activity of the tasg1 was significantly higher than that of WT. In addition, tasg1 plants displayed relatively less accumulation of reactive oxygen species and oxidative damage accompanied by higher activity of some antioxidant enzymes, and the up-regulation of antioxidant genes further demonstrated the improvement of antioxidant activity in tasg1 under salt stress. Furthermore, tasg1 plants also showed relatively weaker Na+ fluorescence and lower Na+ content, but relatively higher content of K+ in their roots and shoots, and then, the roots of tasg1 plants enhanced net outward Na+ flux and a correspondingly increased net inward K+ flux during salt stress. This might be associated with the relatively higher activity of H+-ATPase in tasg1 plants. These results suggest that the improved antioxidant competence and Na+/K+ ion homeostasis play an important role in the enhanced salinity tolerance of tasg1 plants.

Hepatorenal protective effects of medicinal herbs in An-Gong-Niu-Huang Wan (AGNH) against cinnabar- and realgar-induced oxidative stress and inflammatory damage in mice

An-Gong-Niu-Huang Wan (AGNH) is a famous traditional Chinese medicine prescription that contains cinnabar (HgS) and realgar (As2S2); the clinical practice of AGNH is hindered because both mercury and arsenic are hepatorenal toxic metalloids. It is noted that the cinnabar and realgar in AGNH are not used alone, but rather combined with different kinds of medicinal herbs as a formula to use. In this study, we evaluated the hepatorenal protective effects of the medicinal herbs in AGNH after co-exposure to cinnabar and realgar for 4 weeks in mice. The combination of the herbs in AGNH alleviated cinnabar and realgar-induced histopathological alterations and oxidative stress in the liver and kidneys. Furthermore, in cinnabar and realgar-treated mice, the increased expression levels of inducible enzymes (COX-2 and iNOS) and proinflammatory mediators (IL-1β, TNF-α, PGE2 and NO) in the liver and kidneys were consistently down-regulated when medicinal herbs were combined as a formula. We also found that the herbs could reduce the inflammatory response by the inactivation of the MAPK and PI3K/Akt signaling pathway and the resulting blockade of NF-κB activation. Overall, our data indicates that the herbal medicines in AGNH attenuate cinnabar and realgar-induced hepatorenal toxicity by improving antioxidant competence and suppressing inflammatory injury.

Evaluation of the Antioxidant Activity In Vitro and in Hippocampal HT-22 Cells System of Protein Hydrolysates of Common Carp (Cyprinus carpio) By-Product

ABSTRACTFish processing by-products may become more than 50% of the starting material. If mismanaged, these large quantities of discarded fish can create serious pollution problems and can also generate cost associated with their disposal. Enzymatic hydrolysis is one of the techniques that is currently being developed in order to recover and add value to these biomolecules. There is an increasing interest in natural antioxidants that are safer for consumers compared with synthetic antioxidants. In this study, common carp by-product was hydrolyzed using the enzymes Alcalase (A) and Protamex (P) to reach degrees of hydrolysis (DH) of 10 and 15%, respectively. Antioxidant capacity against peroxyl radicals (ACAP); 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging; and the measurement of intracellular reactive oxygen species (ROS) concentration after exposure to common carp protein hydrolysates were investigated. The results revealed that the hydrolysate A15 exhibited significantly (p < 0.05) higher antioxidant activity against the DPPH radical. A15 showed the highest in vitro antioxidant competence against peroxyl radicals, whereas P15 showed the lowest activity against peroxyl radicals (p < 0.05). Hydrolysates having the highest and the lowest in vitro antioxidant activity (A15 and P15, respectively) were selected for the determination of antioxidant activity in the HT-22 cells system. Measurement of intracellular ROS concentration revealed that P15 at the concentration of 1.25 mg/mL significantly (p < 0.05) reduced the intracellular ROS concentration. These results showed that common carp by-product protein hydrolysates are a source of antioxidant peptides with a high potential for food and pharmaceutical industries to develop new nutraceuticals and functional foods.

Antihyperglycemic effect of hesperetin, a citrus flavonoid, extenuates hyperglycemia and exploring the potential role in antioxidant and antihyperlipidemic in streptozotocin-induced diabetic rats

Diabetes is the major health problem in modern civilization which occurs due to inadequate metabolism of carbohydrate and lipid could cause tremendous changes in the metabolic activities of liver. In this study, we investigated the antihyperglycemic, antioxidant and antihyperlipidemic effects of hesperetin, a citrus flavonoid against streptozotocin (STZ)-induced experimental rats. To stimulate diabetes mellitus, rats were injected with STZ intraperitoneally at a single dose of 45mg/kg. STZ induced rats showed marked increase in the level of plasma glucose and significant reduction in the level of plasma insulin. The activities of carbohydrate metabolic enzymes, hepatic glycogen, lipid profiles, enzymic antioxidants in circulatory system and pancreas, hepatic and renal functional markers were explored. Supplementation with hesperetin (40mg/kg b.w) to STZ-induced experimental rats for 45days established a significant decline in plasma glucose and a marked improvement in plasma insulin and glycogen levels in STZ-induced rats. The altered activities of hepatic glucose metabolic enzymes, lipid profiles, enzymic antioxidants and serum biomarkers of liver and kidney toxicity were restored to almost normal. The acquired outcome were compared with glibenclamide (1mg/kg b.w), a standard oral hypoglycemic drug. Hesperetin treatment was found to be efficient in protecting the normal histological manifestation of hepatic, renal and insulin positive β-cells in STZ induced rats. On the basis of current experimental findings, we concluded that administration of hesperetin attenuates the hyperglycemia and dyslipidemia through ameliorating antioxidant competence in STZ-induced experimental rats.

Lipid peroxidation and antioxidant capacity in Peckoltia oligospila (Günther, 1864) submitted to transport under different concentration of dissolved oxygen

It was analyzed antioxidant competence and lipid peroxidation in juveniles of Peckoltia oligospila submitted to transport in plastic bags under different concentrations of dissolved oxygen for up to 24h. Oxidative balance of fish transported for 3, 6, 12, and 24h in normoxic (NX), moderate hyperoxia (MH), and severe hyperoxia (SH) was evaluated. For this, it was determined the total antioxidant capacity against peroxyl radicals (ACAP) and lipid peroxidation levels (TBARS) in liver, gills, muscle, and brain. After 24h and, regardless of water quality, dissolved oxygen concentrations, and duration of transport, no mortality occurred for any of the treatments. The antioxidant competence of P. oligospila in the different organs remained high, except for some occasional decrements. Because of this, TBARS concentration remained low in the different organs, irrespective of transport time or initial oxygen concentrations. According to the results, P. oligospila antioxidant system was efficient enough for the prevention and/or suppression of products derived from lipid peroxidation. Therefore, the oxidative status was not severely affected in the assessed organs over transport time in hyperoxic conditions. Furthermore, Peckoltia oligospila can be safely transported in plastic bags without an extra supply of oxygen for up to 24h, since survival was not affected.

Metabolomics study of cadmium-induced diabetic nephropathy and protective effect of caffeic acid phenethyl ester using UPLC–Q-TOF-MS combined with pattern recognition

Diabetic nephropathy (DN) is the most severe complication of diabetes and multiple factors are involved in the pathogenesis of DN. Among them, cadmium (Cd) acts as a risk factor inducing the occurrence of DN. The present study focused on investigating the protective role of caffeic acid phenethyl ester (CAPE), an active component of propolis from honeybee hives, against Cd-induced DN in mice based on ultra performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC–Q-TOF-MS)and pattern recognition. Serum and urine biochemical indexes were detected and histopathological observation has been done to evaluate the damage of Cd on animals. Moreover, the global serum profiles of different groups were distinguished by UPLC–Q-TOF-MS and principal component analysis (PCA) were applied for group differentiation and marker selection. Moreover, the influence of Cd on the oxidative status in DN mice were also evaluated by assessing the parameters of oxidative stress, proinflammatory cytokines and antioxidant competence. As shown in the scores plots, the distinct clustering among controls, DN and CAPE groups were observed, significant changes in serum levels of LysoPC(18:1(11Z)), 2,3-dinor-8-iso-PGF2a, PS(18:1(9Z)/18:1(9Z)), DG(17:0/22:4 (7Z,10Z, 13Z, 16Z)/0:0) and Arachidonic acid(AA) were noted and identified as potential biomarkers, the effect of CAPE reverted them back to near normalcy. Further, It was observed a significant improvement in lipid peroxides (LPO) and protein carbonyls (PCO) levels in Cd-induced DN kidneys along with a significant decline in superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH) levels, however, CAPE relieved these changes. In conclusion, the study suggested that the pathogenesis of DN caused by Cd probably owes to the perturbations of lipid metabolism and AA metabolism; CAPE seems to be effective agent and may be related to its potent antioxidant, anti-inflammatory properties and action as an Nrf2 activator.

Effect of polysaccharides extracted from Sipunculus nudus (SNP) on the lifespan and immune damage repair of Drosophila melanogaster exposed to Cd (VI)

The water-soluble polysaccharides extracted from Sipunculus nudus (SNP) was investigated on the lifespan and immune damage repair of Drosophila melanogaster exposed to Cd (VI). SNP increased superoxyde dismutase (SOD), nitrogen monoxide (NO), glutathione peroxidase (GSH-Px) and total anti-oxidation competence (T-AOC), with decreased malondialdehyde (MDA) on D. melanogaster demonstrated that SNP could attenuate oxidative damage of D. melanogaster Exposed to Cd (VI). Real-time PCR and western blot analysis showed that SNP enhanced the gene expression of Diptericin, Drosomycin, Defensin, PGRP-LC and the protein level of Toll, p-JNK and Relish， that suggested the promoting effect of SNP on the immune damage repair of D. melanogaster exposed to Cd (VI). The increased level of Indy, Parkin and AMPK indicated the regulated effect of SNP on the longevity-related pathways through ageing-related moleculars of D. melanogaster exposed to Cd (VI). These results suggested that SNP could also improve the lifespan of D. melanogaster exposed to Cd (VI).

Protective effect of Chlorogenic acid against methotrexate induced oxidative stress, inflammation and apoptosis in rat liver: An experimental approach

Methotrexate (MTX) is a drug which is used to treat different types of cancers but hepatotoxicity limits its clinical use. Chlorogenic acid (CGA) is one of the most abundant naturally occurring polyphenols in the human diet. Here, we assessed the effect of CGA against MTX-induced hepatotoxicity and investigated the underlying possible mechanisms in Wistar Rats. Rats were pre-treated with CGA (50 or 100 mg kg/b.w) and administered a single dose of MTX (20 mg/kg, b.w.). MTX caused hepatotoxicity as evidenced by significant increase in serum toxicity markers, histopathological changes. decreased activities of anti-oxidant armory (SOD, CAT, GPx, GR) and GSH content. MTX significantly causes upregulation of iNOS, Cox-2, Bax and downregulation of Bcl-2 expressions, it causes higher caspase 3, 9 activities. However CGA pretreatment alleviates the hepatotoxicity by decreasing the oxidative stress. CGA inhibited Cox-2, iNOS, Bax, Bcl-2 and Caspases 3, 9 mediated inflammation and apoptosis, and improve the histology induced by MTX. Thus, these findings demonstrated the hepatoprotective nature of CGA by attenuating the pro-inflammatory and apoptotic mediators and improving antioxidant competence in hepatic tissue. These results imply that CGA has perfective effect against MTX-induced liver injury. Hence CGA supplementation might be helpful in abrogation of MTX toxicity.

Dietary selenium requirement of juvenile oriental river prawn Macrobrachium nipponense

Selenium (Se) is an essential nutrient for crustaceans. The dietary selenium requirement of juvenile oriental river prawn Macrobrachium nipponense was evaluated. Yeast-selenium was added to basal semi-purified diet at six levels to make diets with the concentration of 0.11, 0.31, 0.47, 0.59, 0.88 and 1.17mgSekg−1. These diets were fed to juvenile prawns (initial weight 0.133±0.003g) in quintuplicate for 8weeks. Our results indicated that the growth performance of prawn was significantly affected by dietary selenium. Prawns fed the 0.47 and 0.59mgSekg−1 diets achieved the highest weight gain rate (WGR), whereas the deficiency (0.11mgkg−1) and excess (1.17mgkg−1) of Selenium inhibited their growth. Whole-body and muscle Se concentrations generally increased with the level of dietary Se. The highest concentrations in body and muscle were observed in the prawns fed the 1.17mgkg−1 diet, which were significantly higher than those of prawns using 0.11, 0.31, 0.47 and 0.59mgkg−1 diets. Selenium also affects the activity of antioxidant enzymes. The activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) were significantly higher in prawns fed with 0.31, 0.47 and 0.59mgSekg−1 than other groups, whereas the maleic dialdehyde (MDA) content had the opposite pattern from GSH-Px activity. Significantly elevated glutathione reductase (GR) activity and reduced glutathione (GSH) content were found in prawns fed the 0.31, 0.47, 0.59 and 0.88mgkg−1 diets. The prawns fed with 0.31–0.88mgSekg−1 exhibited the highest total antioxidant competence (T-AOC activity), which was significantly higher than 1.17mgkg−1 group. Furthermore, selenium is involved in prawn immune competence. Serum phenoloxidase (PO) and lysozyme activities in prawns fed the 0.31, 0.47, 0.59 and 0.88mgSekg−1 diets were significantly higher than those fed the 0.11 and 1.17mgSekg−1 diets. The minimum dietary selenium requirements for maximal growth and antioxidant ability of juvenile oriental river prawn were evaluated as 0.58–0.68mgkg−1 diet based on WGR and GSH-Px activity in the hepatopancreas, and 1.07mgSekg−1 diet was required to maximize whole body selenium content. Statement of relevanceIn this study, we evaluated the minimum dietary selenium requirement for juvenile oriental river prawn Macrobrachium nipponense. Dietary selenium deficiency and excess significantly reduced growth, antioxidant ability and immunity of prawn. Our results illustrate that supplementing appropriate amount of dietary selenium is necessary in prawn culturing. The minimum dietary selenium level for maximal growth and antioxidant ability of juvenile M. nipponense is recommended as 0.58–0.68mgkg−1 diet based on the analyses of WGR and GSH-Px activity, and 1.07mgSekg−1 diet is required to maximize whole body selenium content. This research will facilitate to the development of practical diet for prawn.