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Type II pneumocytes are the target of the SARS-CoV-2 virus, which alters their redox homeostasis to increase reactive oxygen species (ROS). Melatonin (MT) has antioxidant proprieties and protects mitochondrial function. In this study, we evaluated whether treatment with MT compensated for the redox homeostasis alteration in serum from COVID-19 patients. We determined oxidative stress (OS) markers such as carbonyls, glutathione (GSH), total antioxidant capacity (TAC), thiols, nitrites (NO 2 - ), lipid peroxidation (LPO), and thiol groups in serum. We also studied the enzymatic activities of glutathione peroxidase (GPx), glutathione-S-transferase (GST), reductase (GR), thioredoxin reductase (TrxR), extracellular superoxide dismutase (ecSOD) and peroxidases. There were significant increases in LPO and carbonyl quantities ( p ≤ 0.03) and decreases in TAC and the quantities of NO 2 - , thiols, and GSH ( p < 0.001) in COVID-19 patients. The activities of the antioxidant enzymes such as ecSOD, TrxR, GPx, GST, GR, and peroxidases were decreased ( p ≤ 0.04) after the MT treatment. The treatment with MT favored the activity of the antioxidant enzymes that contributed to an increase in TAC and restored the lost redox homeostasis. MT also modulated glucose homeostasis, functioning as a glycolytic agent, and inhibited the Warburg effect. Thus, MT restores the redox homeostasis that is altered in COVID-19 patients and can be used as adjuvant therapy in SARS-CoV-2 infection.

Alcalase hydrolyzates were prepared from the albumin (AH) and globulin (GH) fractions of eight chickpea (Cicer arietinum L.) genotypes from Mexico and 10 from other countries. Protein content, antioxidant activity (AA) (ABTS, DPPH), and degree of hydrolysis were evaluated and the best genotype was selected by principal component analysis. The hydrolyzates of the chosen genotype were analyzed for its antidiabetic potential measured as inhibition of α-amylase, α-glucosidase, and dipeptidyl peptidase-4 (DPP4). Peptide profiles were obtained by liquid chromatography-mass spectrometry (UPLC-DAD-MS), and the most active peptides were analyzed by molecular docking. The average antioxidant activity of albumin hydrolyzates was higher than that of globulin hydrolyzates. ICC3761 was the selected genotype and peptides purified from the albumin hydrolyzate showed the best antioxidant activity and antidiabetic potential (FEI, FEL, FIE, FKN, FGKG, and MEE). FEI, FEL, and FIE were in the same chromatographic peak and this mixture showed the best ABTS scavenging (78.25%) and DPP4 inhibition (IC 50  = 4.20 µg/ml). MEE showed the best DPPH scavenging (47%). FGKG showed the best inhibition of α-amylase (54%) and α-glucosidase (56%) and may be a competitive inhibitor based on in silico-predicted interactions with catalytic amino acids in the active site of both enzymes. These peptides could be used as nutraceutical supplements against diseases related to oxidative stress and diabetes. PRACTICAL APPLICATION: This study showed that chickpea protein hydrolyzates are good sources of peptides with antidiabetic potential, showing high antioxidant activity and inhibition of enzymes related to carbohydrate metabolism and type 2 diabetes. These hydrolyzates could be formulated in functional foods for diabetes., (© 2021 Institute of Food Technologists®.)

Metabolic syndrome (MS) is the association of three or more pathologies among which obesity, hypertension, insulin resistance, dyslipidemia, and diabetes are included. It causes oxidative stress (OS) and renal dysfunction. Hibiscus sabdariffa L. (HSL) is a source of natural antioxidants that may control the renal damage caused by the MS. The objective of this work was to evaluate the effect of a 2% HSL infusion on renal function in a MS rat model induced by the administration of 30% sucrose in drinking water. 24 male Wistar rats were divided into 3 groups: Control rats, MS rats and MS + HSL rats. MS rats had increased body weight, systolic blood pressure, triglycerides, insulin, HOMA index, and leptin ( p ≤ 0.04). Renal function was impaired by an increase in perfusion pressure in the isolated and perfused kidney, albuminuria ( p ≤ 0.03), and by a decrease in clearance of creatinine ( p ≤ 0.04). The activity of some antioxidant enzymes including the superoxide dismutase isoforms, peroxidases, glutathione peroxidase, glutathione-S-transferase was decreased ( p ≤ 0.05). Lipoperoxidation and carbonylation were increased ( p ≤ 0.001). The nitrates/nitrites ratio, total antioxidant capacity, glutathione levels and vitamin C were decreased ( p ≤ 0.03). The treatment with 2% HSL reversed these alterations. The results suggest that the treatment with 2% HSL infusion protects renal function through its natural antioxidants which favor an improved renal vascular response. The infusion contributes to the increase in the glomerular filtration rate, by promoting an increase in the enzymatic and non-enzymatic antioxidant systems leading to a decrease in OS and reestablishing the normal renal function.

Background and objectives: Oxidative stress (OS) participates in the pathophysiology of septic shock, which leads to multiple organ failure (MOF), ischemia-reperfusion injury, and acute respiratory distress syndrome. Therefore, antioxidants have been proposed as therapy. Here, we evaluated the effect of antioxidant treatments in patients with septic shock with MOF and determined levels OS before and after treatment. This study was a randomized, controlled, triple-masked, and with parallel assignment clinical trial with a control group without treatment. Materials and Methods: It included 97 patients of either sex with septic shock. 5 treatments were used each in an independent group of 18 patients. Group 1 received vitamin C (Vit C), group 2 vitamin E (Vit E), group 3 n-acetylcysteine (NAC), group 4 melatonin (MT), and group 5 served as control. All antioxidants were administered orally or through a nasogastric tube for five days as an adjuvant to the standard therapy. Results: The results showed that all patients presented MOF due to sepsis upon admission and that the treatment decreased it ( p = 0.007). The antioxidant treatment with NAC increased the total antioxidant capacity ( p < 0.05). The patients that received Vit C had decreased levels of the nitrate and nitrite ratio ( p < 0.01) and C-reactive protein levels ( p = 0.04). Procalcitonin levels were reduced by Vit E ( p = 0.04), NAC ( p = 0.001), and MT ( p = 0.04). Lipid-peroxidation was reduced in patients that received MT ( p = 0.04). Conclusions: In conclusion, antioxidant therapy associated with standard therapy reduces MOF, OS, and inflammation in patients with septic shock.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) causes the corona virus disease-19 which is accompanied by severe pneumonia, pulmonary alveolar collapses and which stops oxygen exchange. Viral transmissibility and pathogenesis depend on recognition by a receptor in the host, protease cleavage of the host membrane and fusion. SARS-CoV-2 binds to the angiotensin converting enzyme 2 receptor. Here, we discuss the general characteristics of the virus, its mechanism of action and the way in which the mechanism correlates with the comorbidities that increase the death rate. We also discuss the currently proposed therapeutic measures and propose the use of antioxidant drugs to help patients infected with the SARS-CoV-2. Oxidizing agents come from phagocytic leukocytes such as neutrophils, monocytes, macrophages and eosinophils that invade tissue. Free radicals promote cytotoxicity thus injuring cells. They also trigger the mechanism of inflammation by mediating the activation of NFkB and inducing the transcription of cytokine production genes. Release of cytokines enhances the inflammatory response. Oxidative stress is elevated during critical illnesses and contributes to organ failure. In corona virus disease-19 there is an intense inflammatory response known as a cytokine storm that could be mediated by oxidative stress. Although antioxidant therapy has not been tested in corona virus disease-19, the consequences of antioxidant therapy in sepsis, acute respiratory distress syndrome and acute lung injury are known. It improves oxygenation rates, glutathione levels and strengthens the immune response. It reduces mechanical ventilation time, the length of stay in the intensive care unit, multiple organ dysfunctions and the length of stay in the hospital and mortality rates in acute lung injury/acute respiratory distress syndrome and could thus help patients with corona virus disease-19.

In the cocoa bean industry, some by-products go underutilized. Some of these components could provide other innovative products, and such is the case with the husk of the cocoa bean. Previous studies have attributed the husk with a high antioxidant capacity, which added to its relative low cost, makes it an attractive ingredient for the production of infusions. However, prior to promoting it as such, its quality needs to be guaranteed. This study evaluated the chemical composition of the husk of cocoa, its microbiologic quality and other parameters in order to be considered raw material in the preparation of infusions. The cocoa was cultivated in two different states in Venezuela. Moisture, protein, fat, ash, carbohydrates, microbiologic quality and ochratoxin A as well antioxidant properties, content of foreign matter, insoluble ash in HCL and aqueous extract were evaluated in the husk of cocoa seeds. Applied methods were in compliance with national and international norms. Significant differences were determined between the samples through the ANOVA application. A low level in moisture content, but high in ash, along with a microbiologic quality that met the norm, and an absence of ochratoxin A were observed in the totality of the analyzed samples. Low levels of foreign matter, the high value of its aqueous extract and high phenolic compounds content with antioxidant activity allow for the recommendation of the husk of cocoa as raw material for the preparation of infusions.

A dehydrated vegetables mixture loaded in four pharmaceutical dosage forms as powder, effervescent granulate, sugar granulate and gumdrops were investigated for their antioxidant capacity using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging capacity assay, oxygen radical absorbance capacity assay and ferric reducing antioxidant potential assay. Total phenolic content of dehydrated vegetables powder mixture was also measured by the Folin-Ciocalteu method, so as to evaluate its contribution to their total antioxidant function. The effect of different temperatures on stability of these systems after 90 days storage was also evaluated. These formulations presented strong antioxidant properties and high phenolic content (279 mg gallic acid equivalent/g of sample) and thus could be potential rich sources of natural antioxidants. Antioxidant properties differed significantly among selected formulations (p < 0.05). Generally, the losses were lower in samples stored under refrigeration. To interpret the antioxidant properties a kinetic approach was performed. Degradation kinetics for the phenolic content and antioxidant capacity followed a zero-order function. Effervescent granulate was the formulation which underwent faster degradation. Contrary, sugar granulate and gumdrops were much more slowly. Time required to halve the initial amount of phenolic compounds was 589 ± 45 days for samples stored at 4 º C, and 312 ± 16 days for samples stored at room temperature. These developed dosage forms are new and innovative approach for vegetable intakes in population with special requirements providing an improvement in the administration of vegetables and fruits.

Cellular homeostasis is lost or becomes dysfunctional during septic shock due to the activation of the inflammatory response and the deregulation of oxidative stress. Antioxidant therapy administered alongside standard treatment could restore this lost homeostasis. We included 131 patients with septic shock who were treated with standard treatment and vitamin C (Vit C), vitamin E (Vit E), N-acetylcysteine (NAC), or melatonin (MT), in a randomized trial. Organ damage quantified by Sequential Organ Failure Assessment (SOFA) score, and we determined levels of Interleukins (IL) IL1β, Tumor necrosis factor alpha (TNFα), IL-6, monocyte chemoattractant protein-1 (MCP-1), Transforming growth factor B (TGFβ), IL-4, IL-10, IL-12, and Interferon-γ (IFNγ). The SOFA score decreased in patients treated with Vit C, NAC, and MT. Patients treated with MT had statistically significantly reduced of IL-6, IL-8, MCP-1, and IL-10 levels. Lipid peroxidation, Nitrates and nitrites (NO3− and NO2−), glutathione reductase, and superoxide dismutase decreased after treatment with Vit C, Vit E, NAC, and MT. The levels of thiols recovered with the use of Vit E, and all patients treated with antioxidants maintained their selenium levels, in contrast with controls (p = 0.04). The findings regarding oxidative stress markers and cytokines after treatment with antioxidants allow us to consider to future the combined use of antioxidants in a randomized clinical trial with a larger sample to demonstrate the reproducibility of these beneficial effects. [ABSTRACT FROM AUTHOR]

Background and aim: Here, we assess the effect of adjuvant antioxidant therapies in septic shock patients with organ dysfunction and their effect on the enzymatic and non-enzymatic antioxidant systems. Methods: Randomized clinical trial run between 2018 and 2022. One hundred and thirty-one patients with septic shock were included in five groups with 25, 27, 24, 26 and 29 patients each. Group 1 received vitamin C (Vit C), Group 2 vitamin E (Vit E), Group 3 n-acetylcysteine (NAC), Group 4 melatonin (MT) and group 5 no treatment. All antioxidants were administered orally or through a nasogastric tube for 5 days as an adjuvant to standard therapy. Results: All patients had multiple organ failure (MOF) and low Vit C levels. Vit C therapy decreased CRP, PCT and NO3−/NO2– but increased Vit C levels. The SOFA score decreased with MT in 75%, Vit C 63% and NAC 50% vs. controls 33% (p = 0.0001, p = 0.03 and p = 0.001 respectively). MT diminished lipid peroxidation (LPO) (p = 0.01) and improved total antioxidant capacity (TAC) (p = 0.04). Vit E increased thiol levels (p = 0.02) and tended to decrease LPO (p = 0.06). Selenium levels were decreased in the control group (p = 0.04). Conclusions: Antioxidants used as an adjuvant therapy in the standard treatment of septic shock decrease MOF and oxidative stress markers. They increase the TAC and thiols, and maintain selenium levels. [ABSTRACT FROM AUTHOR]

Nejayote is a highly polluting wastewater discarded after the nixtamalization process of maize (Zea mays L.). It contains many organic compounds and unused nutrients. In this study, we optimized the biological treatment of nejayote through Bacillus clausii-induced fermentation, using the response surface methodology, to enhance the content of bioactive compounds, antioxidant and antimicrobial activities of nejayote. The optimal fermentation temperature and time were 36 °C and 4.8 days, respectively, which produced a biomass of 9.1 log10 CFU mL−1 of B. clausii, total phenolic content of 524 mg equivalents of gallic acid per 100 mL sample, and antioxidant activity of 2876 µmol equivalent of trolox per 100 mL sample. The fermentation significantly increased the total phenolic content (~ 150%) and antioxidant activity (~ 30%), increased the content of 8-O-4-hydrodiferulic, 8-O-4-hydrotriferulic, and ferulic acids, and synthesized caffeic acid when compared with non-fermented nejayote. The fermentation process improved the antimicrobial activity of nejayote against Salmonella Typhimurium (3.5-fold) and Enterococcus faecalis (2.72-fold) after 12 h as compared to non-fermented nejayote. B. clausii-fermented nejayote obtained by this alternative eco-friendly process is thus a product with increased bioactive properties that could be used as functional ingredient in different food products. [ABSTRACT FROM AUTHOR]

Objectives: Epilepsy is a common seizure disorder affecting approximately 70 million people worldwide. Mitochondrial dysfunction and antioxidant/prooxidant imbalance are emerging as factors that contribute to epileptogenesis. As medical ozone was able to reestablish cellular redox balance and to maintain the protective effects mediated by A1 receptors (A1Rs), the aim of this work was to study ozone's effects on antioxidant/prooxidant balance and to clarify if A1Rs play a role in ozone's protective actions against pentylenetetrazole (PTZ)-induced convulsions in mice. Methods: Influence of ozone's treatments in mice submitted to PTZ-induced seizures was studied. Ozone was administered by rectal insufflation 1 mg/kg (5, 10, 15, 20 treatments), one per day, of 1-1.5 ml at an ozone concentration of 20 mg/ml. Mice received PTZ (90 mg/kg i.p.) 24 hours after the last ozone treatment. Oxygen control groups 26 mg/kg were introduced. Latency to first seizure was determined. Antioxidant/prooxidant balance in brain homogenates was studied. A1 adenosine receptors' effects on ozone's protective actions against seizures were evaluated using 8-cyclopentyl-1,3-dipropylxanthine (DPCPX). Results: Highest latency was observed when mice received 15 ozone treatments. Oxygen z PTZ group did not achieve protection against neither convulsions nor brain oxidative injury. Fifteen treatments of ozone protected against biomolecules oxidative damage and the antioxidant systems as well. 8-Cyclopentyl-1,3- dipropylxanthine abolished the ozone's protection. Conclusions: Ozone therapy increased the latency for the first seizure and the survival percentage. These effects are discussed in point of ozone's capacity to reestablish cellular redox balance, decrease biomolecules damage, and regulate activation of A1 adenosine receptors in PTZ-induced seizures. [ABSTRACT FROM AUTHOR]

Grape and wine byproducts have been extensively studied for the recovery of phenolic compounds with antioxidant activity and a variety of biological actions. The selective recovery and concentration of the phenolic compounds from the liquid phase separated from further diluted winery wastes has been proposed. Adsorption onto non ionic polymeric resins and further desorption with ethanolic solutions was studied. Several commercial food grade resins were screened with the aim of selecting the most suited for the practical recovery of phenolic compounds with radical scavenging activity. Under the optimized desorption conditions (using Sepabeads SP207 or Diaion HP20 as adsorbents and eluting with 96% ethanol at 50 ° C) a powdered yellow-light brown product with 50% phenolic content, expressed as gallic acid equivalents, was obtained. The radical scavenging capacity of one gram of product was equivalent to 2-3 g of Trolox. [ABSTRACT FROM AUTHOR]

Abstract: Charcoal adsorption of phenolic compounds with antioxidant activity from distilled grape pomace pressing liquors (DPPL) and distilled grape pomace autohydrolysis liquors (DPAL) was carried out under anoxic conditions using commercially available activated charcoals (AC) in powdered, granulated or pelletized form. The adsorption kinetics followed a pseudo-second order rate, and equilibrium was reached in less than 15h. The Langmuir and Freundlich model have been used to describe the equilibrium adsorption data. The maximum adsorption capacity was 239.4mg/g AC. Fixed-bed adsorption and desorption experiments were carried out to assess the recovery and fractionation of products from exhausted AC beds and the AC susceptibility to regeneration. Recovery yields up to 20% were achieved in experiments with 96% ethanol, but neither the purity nor the antioxidant activity of the eluted fractions was affected. Five successive adsorption–desorption cycles with DPPL were performed without loss of adsorption capacity. [Copyright &y& Elsevier]

Summary • The involvement of lipoxygenase and antioxidant enzyme activities as well as hydrogen peroxide (H2O2) accumulation are reported during early infection steps in alfalfa (Medicago sativa) roots inoculated either with a wild type Sinorhizobium meliloti or with a mutant defective in Nod-factor synthesis (Nod C-). • Compatibility between M. sativa and Rhizobium correlates, at least in part, with an increase in the activities of these enzymes, particularly catalase and lipoxygenase, during the preinfection period (up to 12 h). The mutant strain, defective in Nod-factor biosynthesis, showed a decrease in all enzyme activities assayed, and an increase in H2O2 accumulation. • Enhancement of scavenging activities for several reactive oxygen species correlated with compatibility of the S. meliloti–alfalfa symbiosis, whereas the Nod C- strain triggered a defence response. Nod factors were essential to suppress this response. • Increase in lipoxygenase and lipid hydroperoxide decomposing activities, observed during the first hours after inoculation with a compatible strain, could be related to tissue differentiation and/or the production of signal molecules involved in autoregulation of nodulation by the plant. [ABSTRACT FROM AUTHOR]

Andean blackberry is cultivated in Colombia due to its national and international commercial importance, in addition to its flavour and high nutritional value. Due to its physicochemical, morphological, and physiological characteristics, it constitutes one of the most unstable fruits in the Colombian fruit and vegetable supply chain, thereby generating economic losses. In this study, a polymer-based coating of Aloe vera and essential oil was designed, and its influence on the shelf life of Andean blackberry stored at 4 °C was studied. Once the appropriate composition was established according to the experimental design, Andean blackberries' physicochemical parameters, the content of total phenols, and antioxidant activity were monitored over 19 days. The total soluble solids present a change between 5.2 and 5.6° Brix and 5.2 and 7.2° Brix for coated and uncoated fruits between 1 and 19 days, respectively. The coated fruits presented a lower loss compared to the uncoated fruits and the total phenol content presented a higher concentration on day 19 in the coated fruits (412.71 ± 37.5 mg Gallic Acid Equivalents L−1 sample). The coating enabled an increase in the shelf life of the blackberries, from 4 to 19 days, while preserving the physicochemical properties of the fruits. Therefore, the application of coating as a method for the post-harvest preservation of Andean blackberries represents a low-cost, easily available strategy. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Extrusion cooking of cereal‐legume flour mixture is an innovative strategy to introduce nutrient‐enriched ready‐to‐eat snacks to the market. However, this thermal process triggers the formation of compounds that could impact safety aspects of these products. Maillard reaction markers and the end products known as melanoidins were evaluated to assess the toxicological and bioactive profiles of extruded snacks from corn‐plus‐common‐bean‐flour combinations. Different molecular weight fractions were isolated and purified to analyze their antioxidant activity and to investigate the role of melanoidins.The snack formulated with an 84:16 ratio of corn:common bean flours exhibited an enhanced toxicological profile. It displayed the lowest levels of acrylamide and furanic compounds, along with reduced blockage of lysine residues in the protein. Extrusion increased the antioxidant activity of uncooked flours (30 to 64%) and total phenolic compounds (26 to 50%), and decreased the available lysine (−72.7 to −79.5%). During the fractionation process, it was established that compounds within the range of 3–10 kDa made the greatest contribution to antioxidant activity. The fraction greater than 10 kDa, which included melanoidins, displayed 7 to 33% lower antioxidant activity. The purification of the fraction greater than 10 kDa revealed that pure melanoidins represented approximately one‐third of the antioxidant activity in that fraction. Non‐covalent adducts linked to the melanoidin core therefore had a relevant role in the antioxidant action of formulated snacks.This investigation illustrates the importance of considering both potential risks and associated benefits of compounds formed during the Maillard reaction while developing new extruded snacks. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Oxidative stress is important in the pathophysiology of obesity, altering regulatory factors of mitochondrial activity, modifying the concentration of inflammation mediators associated with a large number and size of adipocytes, promoting lipogenesis, stimulating differentiation of preadipocytes to mature adipocytes, and regulating the energy balance in hypothalamic neurons that control appetite. This review discusses the participation of oxidative stress in obesity and the important groups of compounds found in plants with antioxidant properties, which include (a) polyphenols such as phenolic acids, stilbenes, flavonoids (flavonols, flavanols, anthocyanins, flavanones, flavones, flavanonols, and isoflavones), and curcuminoids (b) carotenoids, (c) capsaicinoids and casinoids, (d) isothiocyanates, (e) catechins, and (f) vitamins. Examples are analyzed, such as resveratrol, quercetin, curcumin, ferulic acid, phloretin, green tea, Hibiscus Sabdariffa, and garlic. The antioxidant activities of these compounds depend on their activities as reactive oxygen species (ROS) scavengers and on their capacity to prevent the activation of NF-κB (nuclear factor κ-light-chain-enhancer of activated B cells), and reduce the expression of target genes, including those participating in inflammation. We conclude that natural compounds have therapeutic potential for diseases mediated by oxidative stress, particularly obesity. Controlled and well-designed clinical trials are still necessary to better know the effects of these compounds. [ABSTRACT FROM AUTHOR]