Antioxidants
Latest Publications


TOTAL DOCUMENTS

4523
(FIVE YEARS 4338)

H-INDEX

44
(FIVE YEARS 35)

Published By Mdpi Ag

2076-3921
Updated Monday, 17 January 2022

Antioxidants ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 139
Author(s):  
Paola Montes ◽  
Ana Guerra-Librero ◽  
Paloma García ◽  
María Elena Cornejo-Calvo ◽  
María del Señor López ◽  
...  

This study focused on the impact of the treatment with the hypomethylating agent 5-azacitidine on the redox status and inflammation in 24 MDS patients. Clinical and genetic features of MDS patients were recorded, and peripheral blood samples were used to determine the activity of the endogenous antioxidant defense system (superoxide dismutase, SOD; catalase, CAT; glutathion peroxidase, GPx; and reductase, GRd, activities), markers of oxidative damage (lipid peroxidation, LPO, and advanced oxidation protein products, AOPP). Moreover, pro-inflammatory cytokines and plasma nitrite plus nitrate levels as markers of inflammation, as well as CoQ10 plasma levels, were also measured. Globally, MDS patients showed less redox status in terms of a reduction in the GSSG/GSH ratio and in the LPO levels, as well as increased CAT activity compared with healthy subjects, with no changes in SOD, GPx, and GRd activities, or AOPP levels. When analyzing the evolution from early to advanced stages of the disease, we found that the GPx activity, GSSG/GSH ratio, LPO, and AOPP increased, with a reduction in CAT. GPx changes were related to the presence of risk factors such as high-risk IPSS-R or mutational score. Moreover, there was an increase in IL-2, IL-6, IL-8, and TNF-α plasma levels, with a further increase of IL-2 and IL-10 from early to advanced stages of the disease. However, we did not observe any association between inflammation and oxidative stress. Finally, 5-azacitidine treatment generated oxidative stress in MDS patients, without affecting inflammation levels, suggesting that oxidative status and inflammation are two independent processes.


Antioxidants ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 140
Author(s):  
Evgeny Shchetinin ◽  
Vladimir Baturin ◽  
Eduard Arushanyan ◽  
Albert Bolatchiev ◽  
Dmitriy Bobryshev

The absence of effective drugs for COVID-19 prevention and treatment requires the search for new candidates among approved medicines. Fundamental studies and clinical observations allow us to approach an understanding of the mechanisms of damage and protection from exposure to SARS-CoV-2, to identify possible points of application for pharmacological interventions. In this review we presented studies on the anti-inflammatory, antioxidant, and immunotropic properties of melatonin. We have attempted to present scientifically proven mechanisms of action for the potential therapeutic use of melatonin during SARS-CoV-2 infection. A wide range of pharmacological properties allows its inclusion as an effective addition to the methods of prevention and treatment of COVID-19.


Antioxidants ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 136
Author(s):  
Miguel Rebollo-Hernanz ◽  
Yolanda Aguilera ◽  
Maria A. Martin-Cabrejas ◽  
Elvira Gonzalez de Gonzalez de Mejia

The cocoa shell is a by-product that may be revalorized as a source of bioactive compounds to prevent chronic cardiometabolic diseases. This study aimed to investigate the phytochemicals from the cocoa shell as targeted compounds for activating fibroblast growth factor 21 (FGF21) signaling and regulating non-alcoholic fatty liver disease (NAFLD)-related biomarkers linked to oxidative stress, mitochondrial function, and metabolism in hepatocytes. HepG2 cells treated with palmitic acid (PA, 500 µmol L−1) were used in an NAFLD cell model. Phytochemicals from the cocoa shell (50 µmol L−1) and an aqueous extract (CAE, 100 µg mL−1) enhanced ERK1/2 phosphorylation (1.7- to 3.3-fold) and FGF21 release (1.4- to 3.4-fold) via PPARα activation. Oxidative stress markers were reduced though Nrf-2 regulation. Mitochondrial function (mitochondrial respiration and ATP production) was protected by the PGC-1α pathway modulation. Cocoa shell phytochemicals reduced lipid accumulation (53–115%) and fatty acid synthase activity (59–93%) and prompted CPT-1 activity. Glucose uptake and glucokinase activity were enhanced, whereas glucose production and phosphoenolpyruvate carboxykinase activity were diminished. The increase in the phosphorylation of the insulin receptor, AKT, AMPKα, mTOR, and ERK1/2 conduced to the regulation of hepatic mitochondrial function and energy metabolism. For the first time, the cocoa shell phytochemicals are proved to modulate FGF21 signaling. Results demonstrate the in vitro preventive effect of the phytochemicals from the cocoa shell on NAFLD.


Antioxidants ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 137
Author(s):  
Heike R. Döppler ◽  
Geou-Yarh Liou ◽  
Peter Storz

Pancreatic acinar-to-ductal metaplasia (ADM) is a reversible process that occurs after pancreatic injury, but becomes permanent and leads to pancreatic lesions in the presence of an oncogenic mutation in KRAS. While inflammatory macrophage-secreted chemokines, growth factors that activate epidermal growth factor receptor (EGFR) and oncogenic KRAS have been implicated in the induction of ADM, it is currently unclear whether a common underlying signaling mechanism exists that drives this process. In this study, we show that different inducers of ADM increase levels of hydrogen peroxide, most likely generated at the mitochondria, and upregulate the expression of Protein Kinase D1 (PKD1), a kinase that can be activated by hydrogen peroxide. PKD1 expression in acinar cells affects their survival and mediates ADM, which is in part due to the PKD1 target NF-κB. Overall, our data implicate ROS-PKD1 signaling as a common feature of different inducers of pancreatic ADM.


Antioxidants ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 138
Author(s):  
Marina Liso ◽  
Annamaria Sila ◽  
Giulio Verna ◽  
Aurelia Scarano ◽  
Rossella Donghia ◽  
...  

Antioxidants are privileged candidates for the development of adjuvants able to improve the efficiency of pharmacological therapies, particularly for chronic inflammatory syndromes. During the last 20 years, anti-TNFα (tumor necrosis factor alpha) monoclonal antibodies infusion has been the biological therapy most frequently administered but there is still large space for improvement in disease remission rates and maintenance. In this context, nutritional bioactive compounds contained in dietary patterns or included as supplements, may act as adjuvants for the induction and maintenance of IBD (inflammatory bowel diseases) remission. To verify this possibility, a single-center preliminary study (SI-CURA, Soluzioni Innovative per la gestione del paziente e il follow up terapeutico della Colite UlceRosA) was designed and carried out to evaluate whether a daily administration of purple corn supplement could improve the response to Infliximab (IFX) infusion of IBD patients with both Crohn’s disease (CD) and ulcerative colitis (UC). A cohort of 47 patients was enrolled in the study. Biological samples were collected before the first and the third IFX infusion. All patients received nutritional guidelines, 27 of them received commercial red fruit tea with low anthocyanins content, while 20 received a purple corn supplement with a high anthocyanin content. Results show that the administration of an antioxidant-enriched purple corn supplement could improve IFX-mediated disease remission in terms of circulating inflammatory markers. Comparison between CD and UC patients revealed that, at this anthocyanin dosage, the purple corn extract administration improved the IFX response in CD but not in UC patients. Our results may pave the way for a new metacentric study of CD patients, recruiting a wider cohort and followed-up over a longer observational time.


Antioxidants ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 133
Author(s):  
Hernan Speisky ◽  
Fereidoon Shahidi ◽  
Adriano Costa de Camargo ◽  
Jocelyn Fuentes

Flavonoids display a broad range of health-promoting bioactivities. Among these, their capacity to act as antioxidants has remained most prominent. The canonical reactive oxygen species (ROS)-scavenging mode of the antioxidant action of flavonoids relies on the high susceptibility of their phenolic moieties to undergo oxidation. As a consequence, upon reaction with ROS, the antioxidant capacity of flavonoids is severely compromised. Other phenol-compromising reactions, such as those involved in the biotransformation of flavonoids, can also markedly affect their antioxidant properties. In recent years, however, increasing evidence has indicated that, at least for some flavonoids, the oxidation of such residues can in fact markedly enhance their original antioxidant properties. In such apparent paradoxical cases, the antioxidant activity arises from the pro-oxidant and/or electrophilic character of some of their oxidation-derived metabolites and is exerted by activating the Nrf2–Keap1 pathway, which upregulates the cell’s endogenous antioxidant capacity, and/or, by preventing the activation of the pro-oxidant and pro-inflammatory NF-κB pathway. This review focuses on the effects that the oxidative and/or non-oxidative modification of the phenolic groups of flavonoids may have on the ability of the resulting metabolites to promote direct and/or indirect antioxidant actions. Considering the case of a metabolite resulting from the oxidation of quercetin, we offer a comprehensive description of the evidence that increasingly supports the concept that, in the case of certain flavonoids, the oxidation of phenolics emerges as a mechanism that markedly amplifies their original antioxidant properties. An overlooked topic of great phytomedicine potential is thus unraveled.


Antioxidants ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 135
Author(s):  
Iwona Olszewska-Czyz ◽  
Kristina Kralik ◽  
Marin Tota ◽  
Jelena Prpic

Periodontitis is a common oral disease affecting the tooth-supporting tissues. Bacteria have been long viewed as the main causative factor in its development; however, many investigations have proved that aberrant immune and inflammatory response and the resulting misbalance between the damage caused by reactive oxygen species and the antioxidant capacity of tissues may be an underlying factor in disease progression that reduces healing potential. The objective of the current trial is to assess the outcomes of the addition of hyaluronic acid (HA) to standard non-surgical periodontal therapy (NST) on some major oxidative stress markers in saliva. HA-based gel designed for dental application was used and the measurements were taken after 3 months. HA adjunctive therapy had a significantly greater increase in markers with antioxidant properties as well as total antioxidant capacity compared to standard NST alone. Furthermore, clinically measured levels of gingival inflammation (bleeding on probing-BOP) and periodontal destruction (clinical attachment loss-CAL) were significantly correlated with these markers, and the correlation was negative. This investigation demonstrates that HA may indeed express antioxidant properties and improve the antioxidant capacity of periodontal tissues, thus improving the prognosis for the teeth and the results of periodontal therapy. Further investigations will be necessary to determine the duration of these effects over time.


Antioxidants ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 130
Author(s):  
Jae-Min Lee ◽  
Joo Hee Lee ◽  
Min Kyung Song ◽  
Youn-Jung Kim

Aging is a neurodegenerative disease that leads to cognitive impairment, and an increase in oxidative stress as a major cause is an important factor. It has been reported that aging-related cognitive impairment is associated with increased oxidative damage in several brain regions during aging. As a powerful antioxidant, vitamin C plays an important role in preventing oxidative stress, but due to its unstable chemical properties, it is easily oxidized and thus the activity of antioxidants is reduced. In order to overcome this easily oxidized vulnerability, we developed NXP032 (vitamin C/DNA aptamer complex) that can enhance the antioxidant efficacy of vitamin C using an aptamer. We developed NXP032 (vitamin C/DNA Aptamin C320 complex) that can enhance the antioxidant efficacy of vitamin C using an aptamer. In the present study, we evaluated the neuroprotective effects of NXP032 on aging-induced cognitive decline, oxidative stress, and neuronal damage in 17-month-old female mice. NXP032 was orally administered at 200 mg/kg of ascorbic acid and 4 mg/kg of DNA aptamer daily for eight weeks. Before the sacrifice, a cognitive behavioral test was performed. Administration of NXP032 alleviated cognitive impairment, neuronal damage, microglia activity, and oxidative stress due to aging. We found that although aging decreases the Nrf2-ARE pathway, NXP032 administration activates the Nrf2-ARE pathway to increase the expression of SOD-1 and GSTO1/2. The results suggest that the new aptamer complex NXP032 may be a therapeutic intervention to alleviate aging-induced cognitive impairment and oxidative stress.


Antioxidants ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 131
Author(s):  
Enas A. El-Hawary ◽  
Ahmed Zayed ◽  
Annegret Laub ◽  
Luzia V. Modolo ◽  
Ludger Wessjohann ◽  
...  

Coffee is a popular beverage owing to its unique flavor and diverse health benefits. The current study aimed at investigating the antioxidant activity, in relation to the phytochemical composition, of authenticated Brazilian green and roasted Coffea arabica and C. robusta, along with 15 commercial specimens collected from the Middle East. Ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-ESI–HRMS) and UV spectrometry were employed for profiling and fingerprinting, respectively. With the aid of global natural product social molecular networking (GNPS), a total of 88 peaks were annotated as belonging to different chemical classes, of which 11 metabolites are reported for the first time in coffee seeds. Moreover, chemometric tools showed comparable results between both platforms, with more advantages for UV in the annotation of roasting products, suggesting that UV can serve as a discriminative tool. Additionally, antioxidant assays coupled with the UHPLC-ESI–HRMS dataset using partial least-squares discriminant analysis (PLS-DA) demonstrated that caffeoylquinic acid and caffeine were potential antioxidant markers in unroasted coffee versus dicaffeoyl quinolactone and melanoidins in roasted coffee. The study presents a multiplex metabolomics approach to the quality control of coffee, one of the most consumed beverages.


Antioxidants ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 134
Author(s):  
Gwendolyn van Gorkom ◽  
Birgit Gijsbers ◽  
Erik-Jan Ververs ◽  
Ahmed El Molla ◽  
Cindy Sarodnik ◽  
...  

Given the growing interest in ascorbic acid (AA), there is a need for a reliable and reproducible method to measure AA status in the human body. Serum AA concentrations do not correlate well with tissue levels, but AA levels in leukocytes do. However, a standard method for clinical application is lacking. This present study describes a method to measure AA in the peripheral blood mononuclear cells (PBMCs) with hydrophilic interaction liquid chromatography (HILIC). The method can also be used in plasma and other leukocyte subsets. The measurements of AA in PBMCs and plasma were performed with HPLC with HILIC separation and UV detection. The sample preparation involved the isolation of PBMCs and lysis and precipitation with acetonitrile. European Medicine Agency guidelines for bioanalytic method validation were followed for the evaluation. A highly precise execution of the method was found with intra- and inter-assay variations at a maximum of 7.8%. In 40 healthy donors, a mean intracellular AA concentration of 7.9 microgram/108 cells was found in PBMCs. A correlation between plasma and PBMC AA concentration was not present (r = 0.22). In conclusion, we developed a convenient, reliable, and reproducible method for the quantitative determination of AA within PBMCs and plasma from human blood.


Sign in / Sign up

Export Citation Format

Share Document