scholarly journals Concentration-Dependent Antioxidant/Pro-Oxidant Activity of Ascorbic Acid in Chickens

Author(s):  
Nadežda Berzina ◽  
Jurijs Markovs ◽  
Mirdza Apsīte ◽  
Svetlana Vasiļjeva ◽  
Galina Smirnova ◽  
...  

The effects of ascorbic acid supplementation on biomarkers of oxidative stress, cadmium accumulation in organs, immune system activity and kidney function in chickens were investigated. The treatment groups of chickens were fed either plain diet or diet supplemented with ascorbic acid at 100, 500, 1000 and 2000 mg/kg for four weeks. Liver and kidney tissues were assayed for cadmium concentration, and the hepatic levels of ascorbic acid and dehydroascorbic acid (DHAA; the oxidised form), malondialdehyde, glutathione, activity of glutathione peroxidase, blood serum uric acid, creatinine, lysozyme and circulating immune complexes were measured. Supplementation with a high dose of ascorbic acid (1000 and 2000 mg/kg in the diet) caused an imbalance between pro-oxidative and antioxidative activities, and induced a suppressive effect on innate immunity. The results suggest that oxidative stress compromises renal function. We observed that ascorbic acid increased cadmium accumulation in a dose-dependent manner.

2021 ◽  
Author(s):  
Mosaad Attia Abdel-Wahhab ◽  
Aziza A. El-Nekeety ◽  
Hagar E Mohammed ◽  
Ola I. Elshafey ◽  
Sekena H. Abdel-Aziem ◽  
...  

Abstract The green synthesis of metal nanoparticles is growing dramatically; however, the toxicity of these biosynthesized particles against living organisms is not fully explored. Therefore, this study was designed to synthesize and characterize TiO2-NPs, encapsulation and characterization thyme essential oil (ETEO), determination of the bioactive constituents of ETEO using GC-MS and evaluate their protective role against TiO2-NPs-induced the oxidative damage and genotoxicity in rats. Six groups of rats were treated orally for 30 days including the control group, TiO2-NPs (300 mg/kg b.w)-treated group, ETEO at low (50 mg/kg b.w) or high dose (100 mg/kg b.w)-treated groups TiO2-NPs plus ETEO at the two doses-treated groups. Blood and tissues were collected for different assays. The GC-MS results indicated the presence of 21 compounds belongs to phenols, terpene derivatives, and heterocyclic compounds. The synthesized TiO2-NPs were 45 nm tetragonal particles with a zeta potential of -27.34 mV; however, ETEO were 119 nm round particles with a zeta potential of -28.33 mV. TiO2-NPs administration disturbs the liver and kidney markers, lipid profile, cytokines, oxidative stress parameters, the apoptotic and antioxidant hepatic mRNA expression and induced histological alterations in the liver and kidney tissues. ETEO could improve all these parameters in a dose-dependent manner. It could be concluded that ETEO is a promising candidate for the protection against TiO2-NPs and can be applied safely in food applications.


2010 ◽  
Vol 104 (9) ◽  
pp. 1297-1303 ◽  
Author(s):  
Yan-Hong Huang ◽  
Qing-Hong Zhang

The present study was undertaken to investigate the antioxidant effect of chronic ingestion of genistein (Gen) against neural death in the brain of ovariectomised (Ovx) rats. The rats were randomly divided into five groups, i.e. sham-operated (sham), Ovx-only, Ovx with 17β-oestradiol, Ovx with low (15 mg/kg) and high (30 mg/kg) doses of Gen (Gen-L and Gen-H), and were orally administered daily with drugs or vehicle for 6 weeks. The learning and memory abilities were measured by Morris water maze test. Oxidative damages in the brain were evaluated by the level of superoxide dismutase (SOD), malondialdehyde (MDA) and monoamine oxidase (MAO) activities. Neural apoptosis was shown by terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) staining and caspase-3 activity. In the visual learning and memory test, there were no significant differences among the population means of the five groups. While in the probe trial test, the Gen-L group instead of the Gen-H group exhibited reduced escape latency and increased memory frequency than the Ovx group. Although both doses of Gen could reduce acetylcholinesterase activity, only a low dose of Gen could diminish MDA activity significantly in frontal cortex and enhance SOD content in the hippocampus. In contrast, MAO content was decreased in the cortex by either dose of Gen, while in the hippocampus, only a high dose of Gen appeared to be effective. Interestingly, Gen at both the doses could attenuate the increased number of TUNEL-positive neurons and caspase-3 activity in Ovx rats. These results suggest that Gen confers protection against Ovx-induced neurodegeneration by attenuating oxidative stress, lipid peroxidation and the mitochondria-mediated apoptotic pathway in a region- and dose-dependent manner.


2021 ◽  
Author(s):  
Ahmed M Hamdan ◽  
Zuhair M. Mohammedsaleh ◽  
Aalaa Aboelnour ◽  
Sherif M.H. Elkhannishi

Abstract PurposeThe therapeutic activity of Glyceryl trinitrate (GTN) is mainly regulated by liberating nitric oxide (NO) and reactive nitrogen species (RNS). During this biotransformation, oxidative stress and lipid peroxidation inside the red blood cells (RBCs) occur. The principal objective of our research is to explain the ameliorating effect of L-ascorbic acid for the deleterious effects of chronic administration of nitrovasodilator drugs. MethodsWe studied some biochemical parameters for the oxidative stress using groups of high sucrose/fat (HSF) diet Wistar male rats chronically orally administered ISMN. Afterwards, we evaluated the role of L-ascorbic acid against these biochemical changes. ResultsChronic treatment with organic nitrates caused elevated serum levels of lipid peroxidation, hemoglobin derivatives as methemoglobin and carboxyhemoglobin, rate of hemoglobin autoxidation, the cellular levels of pro-inflammatory cytokines marker (NF-κB) and apoptosis markers (caspase-3) in myocardium muscles in a dose dependent manner. Meanwhile, such exposure caused decline in the enzymatic effect of superoxide dismutase (SOD), glutathione (GSH) and catalase activity (CAT) accompanied with a decrease of in the level of mitochondrial oxidative stress marker (nrf2) in myocardium muscles and decrease in the serum iron and total iron binding capacity (TIBC) in a dose dependent manner. Concomitant treatment with L-ascorbic acid significantly diminished these changes for all examined parameters.ConclusionChronic administration of organic nitrates leads to the alteration of the level of oxidative stress factors in the myocardium tissue due to generation of reactive oxygen species. Using vitamin C can effectively ameliorate such intoxication to overcome the nitrate tolerance.


2021 ◽  
Author(s):  
Tobias Schmidt ◽  
Robin Kahn ◽  
Fredrik Kahn

Objective To investigate the effects of high dose ascorbic acid (AA) on monocyte polarization and cytokine production in vitro Design Experimental in vitro study of cells from healthy subjects and patients with sepsis Setting University research laboratory and academic hospital Subjects Six healthy controls and three patients with sepsis Interventions Monocytes were isolated from whole blood of healthy donors (n=6) and polarized in vitro for 48hrs using LPS or LTA. Polarization was confirmed by surface marker expression using flow cytometry. As a comparison, monocytes were also isolated from septic patients (n=3) and analyzed for polarization markers. The effect of AA on monocyte polarization was evaluated. As a functional assay, AA-treated monocytes were analyzed for cytokine production of TNF and IL-8 by intracellular staining and flow cytometry following activation with LPS or LTA. Measurements and Main Results Both LPS and LTA induced polarization in healthy monocytes in vitro, with increased expression of both pro- (CD40 and PDL1, p<0.05) and anti-inflammatory (CD16 and CD163, p<0.05) polarization markers, with non-significant effects on CD86 and CD206. This pattern resembled, at least partly, that of monocytes from septic patients. Treatment with AA significantly inhibited the upregulation of surface expression of CD16 and CD163 (p<0.05) in a dose dependent manner, but not CD40 or PDL-1. Finally, AA attenuated LPS or LTA-induced cytokine production of IL-8 and TNF in a dose-dependent manner (both p<0.05). Conclusions AA inhibits upregulation of anti-, but not pro-inflammatory related markers in LPS or LTA polarized monocytes. Additionally, AA attenuates cytokine production from in vitro polarized monocytes, displaying functional involvement. This study provides important insight into the immunological effects of high dose AA on monocytes, and potential implications in sepsis.


2020 ◽  
Vol 8 (1) ◽  
pp. e000400 ◽  
Author(s):  
Taiki Kurino ◽  
Reiko Matsuda ◽  
Ayu Terui ◽  
Hiroyuki Suzuki ◽  
Tomomi Kokubo ◽  
...  

BackgroundRecently, antiprogrammed cell death protein 1 (aPD-1) and antiprogrammed death-ligand 1 (aPD-L1) monoclonal antibodies (mAbs) have been approved. Even though aPD-1 and aPD-L1 mAbs target the same PD-1/PD-L1 axis, it is still unclear whether both mAbs exert equivalent pharmacological activity in patients who are sensitive to PD-1/PD-L1 blockade therapy, as there is no direct comparison of their pharmacokinetics (PK) and antitumor effects. Therefore, we evaluated the differences between both mAbs in PK and therapeutic effects in PD-1/PD-L1 blockade-sensitive mouse models.MethodsHerein, murine breast MM48 and colon MC38 xenografts were used to analyze the pharmacological activity of aPD-1 and aPD-L1 mAbs. The PK of the mAbs in the tumor-bearing mice was investigated at low and high doses using two radioisotopes (Indium-111 and Iodine-125) to evaluate the accumulation and degradation of the mAbs.ResultsaPD-1 mAb showed antitumor effect in a dose-dependent manner, indicating that the tumor model was sensitive to PD-1/PD-L1 blockade therapy, whereas aPD-L1 mAb failed to suppress tumor growth. The PK study showed that aPD-L1 mAb was accumulated largely in normal organs such as the spleen, liver, and kidney, resulting in low blood concentration and low distributions to tumors at a low dose, even though the tumors expressed PD-L1. Sufficient accumulation of aPD-L1 mAb in tumors was achieved by administration at a high dose owing to the saturation of target-mediated binding in healthy organs. However, degradation of aPD-L1 mAb in tumors was greater than that of aPD-1 mAb, which resulted in poor outcome presumably due to less inhibition of PD-L1 by aPD-L1 mAb than that of PD-1 by aPD-1 mAb.ConclusionAccording to the PK studies, aPD-1 mAb showed linear PK, whereas aPD-L1 mAb showed non-linear PK between low and high doses. Collectively, the poor PK characteristics of aPD-L1 mAb caused lower antitumor activity than of aPD-1 mAb. These results clearly indicated that aPD-L1 mAb required higher doses than aPD-1 mAb in clinical setting. Thus, targeting of PD-1 would be more advantageous than PD-L1 in terms of PK.


2003 ◽  
Vol 284 (2) ◽  
pp. R550-R557 ◽  
Author(s):  
Roy D. Goldfarb ◽  
Thomas S. Parker ◽  
Daniel M. Levine ◽  
Dana Glock ◽  
Imran Akhter ◽  
...  

Lipoprotein phospholipid (PL) plays a major role in neutralization of endotoxin. This study tested the hypothesis that prophylactic administration of a PL-enriched emulsion (PRE), which augments PL content of serum lipoproteins and neutralizes endotoxin in vitro, would preserve cardiovascular function and improve survival in porcine septic peritonitis. A control group was compared with low-, mid-, and high-dose treatment groups that received PRE by primed continuous infusion for 48 h. A fibrin clot containing live Escherichia coli 0111.B4 was implanted intraperitoneally 30 min after the priming dose. Survival increased in a dose-dependent manner and was correlated with serum PL. Infused PL was associated with high-density lipoprotein in the low-dose group and all serum lipoproteins at higher doses. Treatment significantly lowered serum endotoxin and tumor necrosis factor (TNF)-α, preserved cardiac output and ejection fraction, and attenuated increases in systemic and pulmonary vascular resistances. This study demonstrated that augmentation of lipoprotein PL via administration of PRE improved survival and offered a novel therapeutic approach to sepsis.


2021 ◽  
Author(s):  
Johnmark Ndinawe ◽  
Hellen W. Kinyi

Abstract ObjectiveAmaranths leaves are rich in ascorbic acid and polyphenol compounds which have antioxidant activity. The aim of this study was to evaluate their in vivo antioxidant activity. The effect of consumption of Amaranth leaf extract on in vivo antioxidant activity, catalase enzyme activity and H2O2 induced oxidative stress in Drosophila melanogaster flies was assessed.ResultsConsumption of Amaranth leaf extract was associated with increased survival on exposure to H202 in a dose dependent manner in Drosophila melanogaster flies.


There has been studied the effect of acute blood loss, which was modeled by a single loss of 30% of the circulating blood, on the fluctuations in the content of ascorbic (AA), dehydroascorbic (DAA), diketogulonic (DKGA) acid and their sum in the organs of rats in dynamics for the fifth, twelfth, nineteenth and twenty-sixth days after the blood loss. Acute blood loss caused a significant decrease in the content of all parameters of the system of metabolites of ascorbic acid – their sum, AA, DAA and DKGA – by 10–73 % compared to the control. The most significant decrease was in the content of AA, which was not restored in all organs until the end of the study period. The DAA content in all organs increased from the 12th day, and then decreased during the experiment. The content of the DKGA increased from the 19th day of the experiment. At the same time, it was found that on 26th day in the kidneys, the DAA content exceeded the control value by 42%, and the content of DKGA in the liver and blood – by 25–60 %. The content of the amount of ascorbic acid metabolites at the end of the experiment was almost restored, but this recovery occurred in various ways: in the kidneys – due to an increase in the DAA content, in other organs – by increasing the concentration of DKGA. The parts of AA from the sum of acids (in %) after blood loss significantly decreased, starting from the 5th day, and the process of its recovery began to occur only after the 19th day. The ratio of the amount of the vitamin component of the acids of the ascorbic acid system to the content of the non-vitamin DKGA was increased in the kidneys on the 12th and 26th days of the experiment, in other organs this index decreased 2.3–3.1 times in comparison with the control. The obtained data can be explained by the increased consumption of ascorbic acid to neutralize the effects of the intensification of oxidative processes under oxidative stress, which were activated by the action of acute blood loss, due to its reversible conversion to dehydroascorbic acid, and the latter irreversibly to diketogulonic acid.


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