Blueberry Polyphenol Extracts Enhance the Intestinal Antioxidant Capacity in Weaned Rats by Modulating the Nrf2–Keap1 Signal Pathway

Weaning causes the generation of excessive reactive oxygen species in the body, which could lead to oxidative stress. Polyphenols, for which blueberries are an important dietary source, are known for various health benefits including antioxidant properties. Here, we sought to elucidate the effects of blueberry polyphenol extracts (BPE) on intestinal antioxidant capacity and possible underlying mechanisms in weaned rats. Ninety-six rats were assigned to two groups and fed either a standard diet or a standard diet supplemented with BPE (200 mg/kg). The results showed that BPE supplementation increased (P < 0.05) catalase and superoxide dismutase activities and decreased (P < 0.05) interleukin-1 and interferon-γ contents in the jejunum and ileum. The abundances of mammalian target of rapamycin, ribosomal p70 S6 kinase and eukaryotic initiation factor 4E-binding protein 1 mRNA were elevated in the jejunum and ileum (P < 0.05) after BPE supplementation. Additionally, BPE supplementation decreased (P < 0.05) Kelch-like ECH-associated protein 1 (Keap1) gene transcription and enhanced (P < 0.05) NF-E2-related factor 2 (Nrf2) gene transcription in the jejunum and ileum. According to our results, BPE-induced protective effects against oxidative stress appear through the promotion of the jejunal and ileal antioxidant defense system in weaned rats, which was associated with the Nrf2–Keap1 signaling pathway.

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Mediterranean diet and oxidative stress

Nutrition & Food Science ◽

10.1108/nfs-07-2020-0264 ◽

2020 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Paulina Górska ◽

Ilona Górna ◽

Juliusz Przysławski

Keyword(s):

Oxidative Stress ◽

Antioxidant Capacity ◽

Mediterranean Diet ◽

Antioxidant Properties ◽

The Body ◽

Enzymatic Antioxidants ◽

Critical Approach ◽

Content Type ◽

Varied Diet ◽

The Mediterranean

Purpose This study aims to analyze the antioxidant properties of the Mediterranean diet and describe methods that are used in clinical studies to assess its role in reducing oxidative stress. Design/methodology/approach The review presents the results of interventional and observational clinical trials aimed at assessing the influence of the Mediterranean diet on the level of enzymatic and non-enzymatic antioxidants, as well as the total blood antioxidant capacity. Findings The Mediterranean diet as a varied diet can be a better way to provide antioxidants to the body than supplements. Individual compounds administered in an isolated form can give the opposite effect to the expected, stimulating oxidative stress. The administration of antioxidants in the form of supplements instead of a varied diet is also associated with a lack of synergism of action. In studies on the importance of the Mediterranean diet in the reduction of oxidative stress, single markers are used to measure oxidative damage, the activity of enzymatic antioxidants and the concentration of individual non-enzymatic antioxidants. At the same time, the need to find markers that would assess the level of oxidative stress and the body’s antioxidant capacity more comprehensively is emphasized. Practical implications It should be taken into account that differences between in vivo and in vitro results may result from the fact of various factors, including genetic, smoking, intestinal microflora or diet composition. It is also necessary to answer the question about which marker or set of markers could in the most comprehensive way to assess the level of oxidative stress and the body’s antioxidant capacity. Originality/value The literature review shows not only the source of antioxidants in the Mediterranean diet. This paper also presents a critical approach to markers that allow the assessment of the antioxidant properties of the diet.

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Biochemical Evaluation of the Antioxidant Effects of Hydroxytyrosol on Pancreatitis-Associated Gut Injury

Antioxidants ◽

10.3390/antiox9090781 ◽

2020 ◽

Vol 9 (9) ◽

pp. 781 ◽

Cited By ~ 2

Author(s):

Roberta Fusco ◽

Marika Cordaro ◽

Rosalba Siracusa ◽

Ramona D’Amico ◽

Tiziana Genovese ◽

...

Keyword(s):

Oxidative Stress ◽

Interleukin 1 ◽

Antioxidant Properties ◽

Pancreatic Tissue ◽

Intercellular Adhesion Molecule ◽

Heme Oxygenase 1 ◽

Related Factor ◽

Intercellular Adhesion Molecule 1 ◽

Colon Tissue ◽

Necrosis Factor Alpha

Acute pancreatitis is a severe abdominal pathology often associated with several complications including gut dysfunction. Oxidative stress is one of the most important pathways involved in this pathology. Hydroxytyrosol (HT), a phenolic compound obtained from olive oil, has shown anti-inflammatory and antioxidant properties. We evaluated the effects of HT administration on pancreatic and intestinal injury induced by caerulein administration. CD1 female mice were administered caerulein (50 μg/kg) for 10 h. HT treatment (5 mg/kg) was performed 30 min after the first caerulein injection and for two consecutive hours afterwards. One hour after the last caerulein injection, mice were sacrificed and serum, colon and pancreatic tissue samples were collected. HT was able to reduce the serum hallmarks of pancreatitis (amylase and lipase), histological damage score in both pancreas and colon tissue, inflammatory cells recruitment (mast cells) in both injured tissues, intrapancreatic trypsin activity and overexpression of the adhesion molecules (Intercellular Adhesion Molecule-1 (ICAM-1) and P-selectin) in colon. Additionally, HT reduced cytokine (interleukin 1 beta (IL- 1β), interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α)) levels in serum, pancreas and colon tissue and chemokine release (monocyte chemotactic protein-1 (MCP1/CCL2)) in pancreas and colon tissue. HT decreased lipid peroxidation and oxidative stress (superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione S-transferase (GST) activity) by enhancing the nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) in both injured tissues. Moreover, HT preserved intestinal barrier integrity, as shown by the diamine oxidase (DAO) serum levels and tight junction (zonula occludens (ZO) and occludin) expression in pancreas and colon. Our findings demonstrated that HT would be an important therapeutic tool against pancreatitis-induced injuries in the pancreas and gut.

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Folic Acid Protects Melanocytes from Oxidative Stress via Activation of Nrf2 and Inhibition of HMGB1

Oxidative Medicine and Cellular Longevity ◽

10.1155/2021/1608586 ◽

2021 ◽

Vol 2021 ◽

pp. 1-12

Author(s):

Pengran Du ◽

Shaolong Zhang ◽

Shuli Li ◽

Yuqi Yang ◽

Pan Kang ◽

...

Keyword(s):

Oxidative Stress ◽

Folic Acid ◽

Therapeutic Potential ◽

Antioxidant Properties ◽

Vital Role ◽

Related Factor ◽

Protective Effects ◽

Abnormal Growth ◽

Oxidative Damages ◽

Human Melanocytes

Vitiligo is a cutaneous depigmentation disease due to loss of epidermal melanocytes. Accumulating evidence has indicated that oxidative stress plays a vital role in vitiligo via directly destructing melanocytes and triggering inflammatory response that ultimately undermines melanocytes. Folic acid (FA), an oxidized form of folate with high bioavailability, exhibits potent antioxidant properties and shows therapeutic potential in multiple oxidative stress-related diseases. However, whether FA safeguards melanocytes from oxidative damages remains unknown. In this study, we first found that FA relieved melanocytes from H2O2-induced abnormal growth and apoptosis. Furthermore, FA enhanced the activity of antioxidative enzymes and remarkably reduced intracellular ROS levels in melanocytes. Subsequently, FA effectively activated nuclear factor E2-related factor 2 (Nrf2) pathway, and Nrf2 knockdown blocked the protective effects of FA on H2O2-treated melanocytes. Additionally, FA inhibited the production of proinflammatory HMGB1 in melanocytes under oxidative stress. Taken together, our findings support the protective effects of FA on human melanocytes against oxidative injury via the activation of Nrf2 and the inhibition of HMGB1, thus indicating FA as a potential therapeutic agent for the treatment of vitiligo.

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Transit and Metabolic Pathways of Quercetin in Tubular Cells: Involvement of Its Antioxidant Properties in the Kidney

Antioxidants ◽

10.3390/antiox10060909 ◽

2021 ◽

Vol 10 (6) ◽

pp. 909

Author(s):

Daniel Muñoz-Reyes ◽

Ana I. Morales ◽

Marta Prieto

Keyword(s):

Oxidative Stress ◽

Therapeutic Potential ◽

Antioxidant Properties ◽

The Body ◽

Protective Effects ◽

Metabolic Processes ◽

Intracellular Space ◽

Tubular Cells

Quercetin is a flavonoid with antioxidant, antiviral, antimicrobial, and anti-inflammatory properties. Therefore, it has been postulated as a molecule with great therapeutic potential. The renoprotective capacity of quercetin against various toxins that produce oxidative stress, in both in vivo and in vitro models, has been shown. However, it is not clear whether quercetin itself or any of its metabolites are responsible for the protective effects on the kidney. Although the pharmacokinetics of quercetin have been widely studied and the complexity of its transit throughout the body is well known, the metabolic processes that occur in the kidney are less known. Because of that, the objective of this review was to delve into the molecular and cellular events triggered by quercetin and/or its metabolites in the tubular cells, which could explain some of the protective properties of this flavonoid against oxidative stress produced by toxin administration. Thus, the following are analyzed: (1) the transit of quercetin to the kidney; (2) the uptake mechanisms of quercetin and its metabolites from plasma to the tubular cells; (3) the metabolic processes triggered in those cells, which affect the accumulation of metabolites in the intracellular space; and (4) the efflux mechanisms of these compounds and their subsequent elimination through urine. Finally, it is discussed whether those processes that are mediated in the tubular cells and that give rise to different metabolites are related to the antioxidant and renoprotective properties observed after the administration of quercetin.

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Evaluation of Salivary Antioxidants and Oxidative Stress Markers in Male Smokers

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207322666190806123616 ◽

2019 ◽

Vol 22 (7) ◽

pp. 496-501

Author(s):

Fatemeh Ahmadi-Motamayel ◽

Parisa Falsafi ◽

Hamidreza Abolsamadi ◽

Mohammad T. Goodarzi ◽

Jalal Poorolajal

Keyword(s):

Oxidative Stress ◽

Uric Acid ◽

Free Radicals ◽

Antioxidant Capacity ◽

Cigarette Smoke ◽

Total Antioxidant Capacity ◽

The Body ◽

Total Antioxidant ◽

The Mean ◽

And Oxidative Stress

Background: Cigarette smoke free radicals can cause cellular damage and different diseases. All the body fluids have antioxidants which protect against free radicals. Objective: The aim of this study was to evaluate salivary total antioxidant capacity and peroxidase, uric acid and malondialdehyde levels in smokers and a nonsmoking control group. Methods: Unstimulated saliva was collected from 510 males. A total of 259 subjects were current smokers and 251 were non-smokers. The levels of salivary total antioxidant capacity, uric acid, peroxidase and malondialdehyde were measured using standard procedures. Data were analyzed with t test and ANOVA. Results: The smokers were younger and dental hygiene index was higher than healthy nonsmoking controls. The mean total antioxidant capacity in smokers and nonsmokers was 0.13±0.07 and 0.21±011, respectively (P=0.001). Smokers had significantly lower peroxidase and uric acid levels than healthy controls. In addition, the mean malondialdehyde levels in the smokers and nonsmokers were 4.55 ±2.61 and 2.79 ±2.21, respectively (P=0.001). Conclusion: Cigarette smoke produces free radical and oxidative stress, causing many side effects. Salivary antioxidant levels decreased and malondialdehyde levels increased in smokers, indicating the high oxidative stress among smokers compared to nonsmokers. Cigarette smoke had deleterious effects on main salivary antioxidants levels.

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Protective Effects of GYY4137 on Renal Ischaemia/Reperfusion Injury through Nrf2-Mediated Antioxidant Defence

Kidney & Blood Pressure Research ◽

10.1159/000509933 ◽

2021 ◽

pp. 1-9

Author(s):

Hongmei Zhao ◽

Yun Qiu ◽

Yichen Wu ◽

Hong Sun ◽

Sumin Gao

Keyword(s):

Oxidative Stress ◽

Reperfusion Injury ◽

Nuclear Translocation ◽

Organ Damage ◽

Related Factor ◽

Protective Effects ◽

Ischaemia Reperfusion Injury ◽

Renal Ischaemia ◽

Ischaemia Reperfusion ◽

Renal Histology

Introduction/Aims: Hydrogen sulfide (H2S) is considered to be the third most important endogenous gasotransmitter in organisms. GYY4137 is a long-acting donor for H2S, a gas transmitter that has been shown to prevent multi-organ damage in animal studies. We previously reported the effect of GYY4137 on cardiac ischaemia reperfusion injury (IRI) in diabetic mice. However, the role and mechanism of GYY4137 in renal IRI are poorly understood. The aims of this study were to determine whether GYY4137 can effectively alleviate the injury induced by renal ischaemia reperfusion and to explore its possible mechanism. Methods: Mice received right nephrectomy and clipping of the left renal pedicle for 45 min. GYY4137 was administered by intraperitoneal injection for 2 consecutive days before the operation. The model of hypoxia/reoxygenation injury was established in HK-2 cells, which were pre-treated with or without GYY4137. Renal histology, function, apoptosis, and oxidative stress were measured. Western blot was used to measure the target protein after renal IRI. Results: The results indicated that GYY4137 had a clear protective effect on renal IRI as reflected by the attenuation of renal dysfunction, renal tubule injury, and apoptosis. Moreover, GYY4137 remarkably reduced renal IRI-induced oxidative stress. GYY4137 significantly elevated the nuclear translocation of nuclear factor-erythroid-2-related factor 2 (Nrf2) and the expression of antioxidant enzymes regulated by Nrf2, including SOD, HO-1, and NQO-1. Conclusions: GYY4137 alleviates ischaemia reperfusion-induced renal injury through activating the antioxidant effect mediated by Nrf2 signalling.

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How to express the antioxidant properties of substances properly?

Chemical Papers ◽

10.1007/s11696-021-01799-1 ◽

2021 ◽

Author(s):

Małgorzata Olszowy-Tomczyk

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Literature Review ◽

Antioxidant Activities ◽

Antioxidant Properties ◽

Reactive Oxygen ◽

The Body ◽

Universal Method ◽

Oxygen Species ◽

Good Tool

AbstractOxidative stress, associated with an imbalance between the oxidants (reactive oxygen species) and the antioxidants in the body, contributes to the development of many diseases. The body’s fight against reactive oxygen species is supported by antioxidants. Nowadays, there are too many analytical methods, but there is no one universal technique for assessing antioxidant properties. Moreover, the applied different ways of expressing the results lead to their incompatibility and unreasonable interpretation. The paper is a literature review concerning the most frequent ways of antioxidant activities expression and for an easy and universal method of the obtained results discussion. This paper is an attempt to point out their disadvantages and advantages. The manuscript can support the searching interpretation of the obtained results which will be a good tool for the development of a number of fields, especially medicine what can help in the future detection and treatment of many serious diseases. Graphic abstract

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Beneficial Role of Carica papaya Extracts and Phytochemicals on Oxidative Stress and Related Diseases: A Mini Review

Biology ◽

10.3390/biology10040287 ◽

2021 ◽

Vol 10 (4) ◽

pp. 287

Author(s):

Yew Rong Kong ◽

Yong Xin Jong ◽

Manisha Balakrishnan ◽

Zhui Ken Bok ◽

Janice Kwan Kah Weng ◽

...

Keyword(s):

Oxidative Stress ◽

Signaling Pathways ◽

Chronic Diseases ◽

Carica Papaya ◽

Antioxidant Properties ◽

Natural Antioxidants ◽

The Body ◽

Health Conditions ◽

Chemical Components ◽

Impaired Wound Healing

Oxidative stress is a result of disruption in the balance between antioxidants and pro-oxidants in which subsequently impacting on redox signaling, causing cell and tissue damages. It leads to a range of medical conditions including inflammation, skin aging, impaired wound healing, chronic diseases and cancers but these conditions can be managed properly with the aid of antioxidants. This review features various studies to provide an overview on how Carica papaya help counteract oxidative stress via various mechanisms of action closely related to its antioxidant properties and eventually improving the management of various oxidative stress-related health conditions. Carica papaya is a topical plant species discovered to contain high amounts of natural antioxidants that can usually be found in their leaves, fruits and seeds. It contains various chemical compounds demonstrate significant antioxidant properties including caffeic acid, myricetin, rutin, quercetin, α-tocopherol, papain, benzyl isothiocyanate (BiTC), and kaempferol. Therefore, it can counteract pro-oxidants via a number of signaling pathways that either promote the expression of antioxidant enzymes or reduce ROS production. These signaling pathways activate the antioxidant defense mechanisms that protect the body against both intrinsic and extrinsic oxidative stress. To conclude, Carica papaya can be incorporated into medications or supplements to help manage the health conditions driven by oxidative stress and further studies are needed to investigate the potential of its chemical components to manage various chronic diseases.

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Kaempferol Ameliorates Oxygen-Glucose Deprivation/Reoxygenation-Induced Neuronal Ferroptosis by Activating Nrf2/SLC7A11/GPX4 Axis

Biomolecules ◽

10.3390/biom11070923 ◽

2021 ◽

Vol 11 (7) ◽

pp. 923

Author(s):

Yuan Yuan ◽

Yanyu Zhai ◽

Jingjiong Chen ◽

Xiaofeng Xu ◽

Hongmei Wang

Keyword(s):

Lipid Peroxidation ◽

Cell Death ◽

Antioxidant Capacity ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Nicotinamide Adenine Dinucleotide Phosphate ◽

Glucose Deprivation ◽

Oxygen Glucose Deprivation ◽

Related Factor ◽

Protective Effects

Kaempferol has been shown to protect cells against cerebral ischemia/reperfusion injury through inhibition of apoptosis. In the present study, we sought to investigate whether ferroptosis is involved in the oxygen-glucose deprivation/reperfusion (OGD/R)-induced neuronal injury and the effects of kaempferol on ferroptosis in OGD/R-treated neurons. Western blot, immunofluorescence, and transmission electron microscopy were used to analyze ferroptosis, whereas cell death was detected using lactate dehydrogenase (LDH) release. We found that OGD/R attenuated SLC7A11 and glutathione peroxidase 4 (GPX4) levels as well as decreased endogenous antioxidants including nicotinamide adenine dinucleotide phosphate (NADPH), glutathione (GSH), and superoxide dismutase (SOD) in neurons. Notably, OGD/R enhanced the accumulation of lipid peroxidation, leading to the induction of ferroptosis in neurons. However, kaempferol activated nuclear factor-E2-related factor 2 (Nrf2)/SLC7A11/GPX4 signaling, augmented antioxidant capacity, and suppressed the accumulation of lipid peroxidation in OGD/R-treated neurons. Furthermore, kaempferol significantly reversed OGD/R-induced ferroptosis. Nevertheless, inhibition of Nrf2 by ML385 blocked the protective effects of kaempferol on antioxidant capacity, lipid peroxidation, and ferroptosis in OGD/R-treated neurons. These results suggest that ferroptosis may be a significant cause of cell death associated with OGD/R. Kaempferol provides protection from OGD/R-induced ferroptosis partly by activating Nrf2/SLC7A11/GPX4 signaling pathway.

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Ethanol Extract of Maclura tricuspidata Fruit Protects SH-SY5Y Neuroblastoma Cells against H2O2-Induced Oxidative Damage via Inhibiting MAPK and NF-κB Signaling

International Journal of Molecular Sciences ◽

10.3390/ijms22136946 ◽

2021 ◽

Vol 22 (13) ◽

pp. 6946

Author(s):

Weishun Tian ◽

Suyoung Heo ◽

Dae-Woon Kim ◽

In-Shik Kim ◽

Dongchoon Ahn ◽

...

Keyword(s):

Oxidative Stress ◽

Free Radical ◽

Oxidative Damage ◽

Cell Damage ◽

Antioxidant Properties ◽

Radical Scavenging ◽

Biologically Active ◽

Mitogen Activated Protein Kinase ◽

Protective Effects ◽

Neuroprotective Effects

Free radical generation and oxidative stress push forward an immense influence on the pathogenesis of neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s disease. Maclura tricuspidata fruit (MT) contains many biologically active substances, including compounds with antioxidant properties. The current study aimed to investigate the neuroprotective effects of MT fruit on hydrogen peroxide (H2O2)-induced neurotoxicity in SH-SY5Y cells. SH-SY5Y cells were pretreated with MT, and cell damage was induced by H2O2. First, the chemical composition and free radical scavenging properties of MT were analyzed. MT attenuated oxidative stress-induced damage in cells based on the assessment of cell viability. The H2O2-induced toxicity caused by ROS production and lactate dehydrogenase (LDH) release was ameliorated by MT pretreatment. MT also promoted an increase in the expression of genes encoding the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT). MT pretreatment was associated with an increase in the expression of neuronal genes downregulated by H2O2. Mechanistically, MT dramatically suppressed H2O2-induced Bcl-2 downregulation, Bax upregulation, apoptotic factor caspase-3 activation, Mitogen-activated protein kinase (MAPK) (JNK, ERK, and p38), and Nuclear factor-κB (NF-κB) activation, thereby preventing H2O2-induced neurotoxicity. These results indicate that MT has protective effects against H2O2-induced oxidative damage in SH-SY5Y cells and can be used to prevent and protect against neurodegeneration.

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