Antioxidants

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4 pages, 192 KiB

Open AccessEditorial

Oxidative Stress Modulators and Functional Foods

by Junsei Taira

Antioxidants 2021, 10(2), 191; https://doi.org/10.3390/antiox10020191 - 29 Jan 2021

Cited by 4 | Viewed by 2094

Abstract

Many years of research have seen the investigation of natural antioxidants and dietary supplements as functional foods with the potential to prevent oxidative stress due to the scavenging of reactive oxygen species (ROS) and reactive nitrogen species (RNS) [...] Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

Research

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14 pages, 3009 KiB

Open AccessArticle

Cudratricusxanthone O Inhibits H₂O₂-Induced Cell Damage by Activating Nrf2/HO-1 Pathway in Human Chondrocytes

by Eun-Nam Kim, Hyun-Su Lee and Gil-Saeng Jeong

Antioxidants 2020, 9(9), 788; https://doi.org/10.3390/antiox9090788 - 25 Aug 2020

Cited by 14 | Viewed by 4311

Abstract

Osteoarthritis (OA) is a common joint degenerative disease induced by oxidative stress in chondrocytes. Although induced-heme oxygenase-1 (HO-1) has been found to protect cells against oxygen radical damage, little information is available regarding the use of bioactive compounds from natural sources for regulating [...] Read more.

Osteoarthritis (OA) is a common joint degenerative disease induced by oxidative stress in chondrocytes. Although induced-heme oxygenase-1 (HO-1) has been found to protect cells against oxygen radical damage, little information is available regarding the use of bioactive compounds from natural sources for regulating the HO-1 pathway to treat OA. In this study, we explored the inhibitory effects of cudratricusxanthone O (CTO) isolated from the Maclura tricuspidata Bureau (Moraceae) on H₂O₂-induced damage of SW1353 chondrocytes via regulation of the HO-1 pathway. CTO promoted HO-1 expression by enhancing the translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) into the nucleus without inducing toxicity. Pretreatment with CTO-regulated reactive oxygen species (ROS) production by inducing expression of antioxidant enzymes in H₂O₂-treated cells and maintained the functions of H₂O₂-damaged chondrocytes. Furthermore, CTO prevented H₂O₂-induced apoptosis by regulating the expression of anti-apoptotic proteins. Treatment with the HO-1 inhibitor tin-protoporphyrin IX revealed that these protective effects were exerted due to an increase in HO-1 expression induced by CTO. In conclusion, CTO protects chondrocytes from H₂O₂-induced damages—including ROS accumulation, dysfunction, and apoptosis through activation of the Nrf2/HO-1 signaling pathway in chondrocytes and, therefore, is a potential therapeutic agent for OA treatment. Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

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13 pages, 1262 KiB

Open AccessArticle

Modulation and Protection Effects of Antioxidant Compounds against Oxidant Induced Developmental Toxicity in Zebrafish

by Nuria Boix, Elisabet Teixido, Ester Pique, Juan Maria Llobet and Jesus Gomez-Catalan

Antioxidants 2020, 9(8), 721; https://doi.org/10.3390/antiox9080721 - 8 Aug 2020

Cited by 10 | Viewed by 3492

Abstract

The antioxidant effect of compounds is regularly evaluated by in vitro assays that do not have the capability to predict in vivo protective activity or to determine their underlying mechanisms of action. The aim of this study was to develop an experimental system [...] Read more.

The antioxidant effect of compounds is regularly evaluated by in vitro assays that do not have the capability to predict in vivo protective activity or to determine their underlying mechanisms of action. The aim of this study was to develop an experimental system to evaluate the in vivo protective effects of different antioxidant compounds, based on the zebrafish embryo test. Zebrafish embryos were exposed to tert-butyl hydroperoxide (tBOOH), tetrachlorohydroquinone (TCHQ) and lipopolysaccharides from Escherichia coli (LPS), chemicals that are known inducers of oxidative stress in zebrafish. The developmental toxic effects (lethality or dysmorphogenesis) induced by these chemicals were modulated with n-acetyl l-cysteine and Nω-nitro l-arginine methyl ester hydrochloride, dimethyl maleate and dl-buthionine sulfoximine in order to validate the oxidant mechanism of oxidative stress inducers. The oxidant effects of tBOOH, TCHQ, and LPS were confirmed by the determination of significant differences in the comparison between the concentration–response curves of the oxidative stress inducers and of the modulators of antioxidant status. This concept was also applied to the study of the effects of well-known antioxidants, such as vitamin E, quercetin, and lipoic acid. Our results confirm the zebrafish model as an in vivo useful tool to test the protective effects of antioxidant compounds. Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

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13 pages, 1869 KiB

Open AccessArticle

Antioxidative Action of Ellagic Acid—A Kinetic DFT Study

by Jelena Tošović and Urban Bren

Antioxidants 2020, 9(7), 587; https://doi.org/10.3390/antiox9070587 - 6 Jul 2020

Cited by 49 | Viewed by 5381

Abstract

Although one can find numerous studies devoted to the investigation of antioxidative activity of ellagic acid (EA) in the scientific literature, the mechanisms of its action have not yet been fully clarified. Therefore, further kinetic studies are needed to understand its antioxidative capacity [...] Read more.

Although one can find numerous studies devoted to the investigation of antioxidative activity of ellagic acid (EA) in the scientific literature, the mechanisms of its action have not yet been fully clarified. Therefore, further kinetic studies are needed to understand its antioxidative capacity completely. This work aims to reveal the underlying molecular mechanisms responsible for the antioxidative action of EA. For this purpose, its reactions with HO^• and CCl₃OO^• radicals were simulated at physiological conditions using the quantum mechanics-based test for overall free-radical scavenging activity. The density functional theory in combination with the conductor-like polarizable continuum solvation model was utilized. With HO^• radical EA conforms to the hydrogen atom transfer and radical adduct formation mechanisms, whereas sequential proton loss electron transfer mechanism is responsible for scavenging of CCl₃OO^• radical. In addition, compared to trolox, EA was found more reactive toward HO^•, but less reactive toward CCl₃OO^•. The calculated rate constants for the reactions of EA with both free radicals are in a very good agreement with the corresponding experimental values. Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

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22 pages, 579 KiB

Open AccessArticle

Chemical Composition and Biological Activities of the Nord-West Romanian Wild Bilberry (Vaccinium myrtillus L.) and Lingonberry (Vaccinium vitis-idaea L.) Leaves

by Bianca-Eugenia Ștefănescu, Lavinia Florina Călinoiu, Floricuța Ranga, Florinela Fetea, Andrei Mocan, Dan Cristian Vodnar and Gianina Crișan

Antioxidants 2020, 9(6), 495; https://doi.org/10.3390/antiox9060495 - 5 Jun 2020

Cited by 62 | Viewed by 5955

Abstract

This study was performed to evaluate and compare the in vitro antioxidant, antimicrobial, and antimutagenic activities, and the polyphenolic content of the Nord-West Romanian wild bilberry (Vaccinium myrtillus L.) and lingonberry (Vaccinium vitis-idaea L.) leaves from three different natural habitats (Smida, [...] Read more.

This study was performed to evaluate and compare the in vitro antioxidant, antimicrobial, and antimutagenic activities, and the polyphenolic content of the Nord-West Romanian wild bilberry (Vaccinium myrtillus L.) and lingonberry (Vaccinium vitis-idaea L.) leaves from three different natural habitats (Smida, Turda, Borsa). In the case of both species, the flavanols level was higher in Smida habitat (altitude 1100 m), whereas quercetin derivates were more abundant in Borsa habitat (altitude 850 m). The bilberry leaf extracts contained in the highest amounts the feruloylquinic acid (59.65 ± 0.44 mg/g for Borsa habitat) and rutin (49.83 ± 0.63 mg/g for Borsa habitat), and showed relevant 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant activity (271.65 mM Trolox/100 g plant material for Borsa habitat, 262.77 mM Trolox/100 g plant material for Smida habitat, and 320.83 mM Trolox/100 g plant material for Turda habitat), for all the three extracts. Gallocatechin was the dominant flavanol in lingonberry species, with the highest amount being registered for Smida habitat (46.81 ± 0.3 mg/g), revealing a DPPH antioxidant activity of 251.49 mM Trolox/100 g plant material. The results obtained in the antimicrobial tests showed that the best inhibitory effect among bilberry species was attributed to the Turda (altitude 436 m) and Smida locations, against both Gram-positive and Gram-negative bacterial strains. For lingonberry, the differences in habitat did not influence the antibacterial effect, but the antifungal effect, only in the case of Candida zeylanoides. A strong antimutagenic effect was registered by the bilberry leaves toward Salmonella typhimurium TA100. Our study may be able to provide a better understanding of the correlation between natural habitat conditions and the accumulation of secondary metabolites and their related bioactivities in studied leaves. Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

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12 pages, 18904 KiB

Open AccessArticle

(−)-Loliolide Isolated from Sargassum horneri Protects against Fine Dust-Induced Oxidative Stress in Human Keratinocytes

by Mawalle Kankanamge Hasitha Madhawa Dias, Dissanayaka Mudiyanselage Dinesh Madusanka, Eui Jeong Han, Min Ju Kim, You-Jin Jeon, Hyun-Soo Kim, Ilekuttige Priyan Shanura Fernando and Ginnae Ahn

Antioxidants 2020, 9(6), 474; https://doi.org/10.3390/antiox9060474 - 2 Jun 2020

Cited by 25 | Viewed by 4861

Abstract

The emergence of fine dust (FD) among air pollutants has taken a toll during the past few decades, and it has provided both controversy and a platform for open conversation amongst world powers for finding sustainable solutions and effective treatments for health issues. [...] Read more.

The emergence of fine dust (FD) among air pollutants has taken a toll during the past few decades, and it has provided both controversy and a platform for open conversation amongst world powers for finding sustainable solutions and effective treatments for health issues. The present study emphasizes the protective effects of (–)-loliolide (HTT) isolated from Sargassum horneri against FD-induced oxidative stress in human HaCaT keratinocytes. The purification of (–)-loliolide was carried out by centrifugal partition chromatography. HTT did not show any cytotoxicity, and it further illustrated the potential to increase cell viability by reducing the reactive oxygen species (ROS) production in FD-stimulated keratinocytes. Furthermore, HTT suppressed FD-stimulated DNA damage and the formation of apoptotic bodies, and it reduced the population of cells in the sub-G₁ apoptosis phase. FD-induced apoptosis was advancing through the mitochondria-mediated apoptosis pathway. The cytoprotective effects of the HTT against FD-stimulated oxidative damage is mediated through squaring the nuclear factor E2-related factor 2 (Nrf2)-mediated heme oxygenase-1 (HO-1) pathway, dose-dependently increasing HO-1 and NAD(P)H dehydrogenase (quinone) 1 (NQO1) levels in the cytosol while concomitantly improving the nuclear translocation of Nrf2. Future studies could implement the protective functionality of HTT in producing pharmaceuticals that utilize natural products and benefit the diseased. Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

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17 pages, 4574 KiB

Open AccessArticle

Effect of Quamoclit angulata Extract Supplementation on Oxidative Stress and Inflammation on Hyperglycemia-Induced Renal Damage in Type 2 Diabetic Mice

by Ji Eun Park, Heaji Lee, Hyunkyung Rho, Seong Min Hong, Sun Yeou Kim and Yunsook Lim

Antioxidants 2020, 9(6), 459; https://doi.org/10.3390/antiox9060459 - 27 May 2020

Cited by 15 | Viewed by 4253

Abstract

Type 2 diabetes mellitus (T2DM) is caused by abnormalities of controlling blood glucose and insulin homeostasis. Especially, hyperglycemia causes hyper-inflammation through activation of NLRP3 inflammasome, which can lead to cell apoptosis, hypertrophy, and fibrosis. Quamoclit angulata (QA), one of the annual winders, has [...] Read more.

Type 2 diabetes mellitus (T2DM) is caused by abnormalities of controlling blood glucose and insulin homeostasis. Especially, hyperglycemia causes hyper-inflammation through activation of NLRP3 inflammasome, which can lead to cell apoptosis, hypertrophy, and fibrosis. Quamoclit angulata (QA), one of the annual winders, has been shown ameliorative effects on diabetes. The current study investigated whether the QA extract (QAE) attenuated hyperglycemia-induced renal inflammation related to NLRP inflammasome and oxidative stress in high fat diet (HFD)-induced diabetic mice. After T2DM was induced, the mice were treated with QAE (5 or 10 mg/kg/day) by gavage for 12 weeks. The QAE supplementation reduced homeostasis model assessment insulin resistance (HOMA-IR), kidney malfunction, and glomerular hypertrophy in T2DM. Moreover, the QAE treatment significantly attenuated renal NLRP3 inflammasome dependent hyper-inflammation and consequential renal damage caused by oxidative stress, apoptosis, and fibrosis in T2DM. Furthermore, QAE normalized aberrant energy metabolism (downregulation of p-AMPK, sirtuin (SIRT)-1, and PPARγ-coactivator α (PGC-1 α)) in T2DM mice. Taken together, the results suggested that QAE as a natural product has ameliorative effects on renal damage by regulation of oxidative stress and inflammation in T2DM. Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

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13 pages, 1902 KiB

Open AccessEditor’s ChoiceArticle

Protective Effects of Myricetin on Benzo[a]pyrene-Induced 8-Hydroxy-2′-Deoxyguanosine and BPDE-DNA Adduct

by Seung-Cheol Jee, Min Kim, Kyeong Seok Kim, Hyung-Sik Kim and Jung-Suk Sung

Antioxidants 2020, 9(5), 446; https://doi.org/10.3390/antiox9050446 - 21 May 2020

Cited by 29 | Viewed by 4495

Abstract

Benzo[a]pyrene (B[a]P), a group 1 carcinogen, induces mutagenic DNA adducts. Myricetin is present in many natural foods with diverse biological activities, such as anti-oxidative and anti-cancer activities. The aim of this study was to investigate the protective effects of myricetin against B[a]P-induced toxicity. [...] Read more.

Benzo[a]pyrene (B[a]P), a group 1 carcinogen, induces mutagenic DNA adducts. Myricetin is present in many natural foods with diverse biological activities, such as anti-oxidative and anti-cancer activities. The aim of this study was to investigate the protective effects of myricetin against B[a]P-induced toxicity. Treatment of B[a]P induced cytotoxicity on HepG2 cells, whereas co-treatment of myricetin with B[a]P reduced the formation of the B[a]P-7,8-dihydrodiol-9,10-epoxide (BPDE)-DNA adduct, which recovered cell viability. Furthermore, we found a protective effect of myricetin against B[a]P-induced genotoxicity in rats, via myricetin-induced inhibition of 8-hydroxy-2′-deoxyguanosine (8-OHdG) and BPDE-DNA adduct formation in the liver, kidney, colon, and stomach tissue. This inhibition was more prominent in the liver than in other tissues. Correspondingly, myricetin regulated the phase I and II enzymes that inhibit B[a]P metabolism and B[a]P metabolites conjugated with DNA by reducing and inducing CYP1A1 and glutathione S-transferase (GST) expression, respectively. Taken together, this showed that myricetin attenuated B[a]P-induced genotoxicity via regulation of phase I and II enzymes. Our results suggest that myricetin is anti-genotoxic, and prevents oxidative DNA damage and BPDE-DNA adduct formation via regulation of phase I and II enzymes. Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

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12 pages, 2906 KiB

Open AccessArticle

Nitric Oxide Modulation by Folic Acid Fortification

by Junsei Taira and Takayuki Ogi

Antioxidants 2020, 9(5), 393; https://doi.org/10.3390/antiox9050393 - 7 May 2020

Cited by 2 | Viewed by 4422

Abstract

Folic acid (FA) can be protected the neural tube defects (NTDs) causing nitric oxide (NO) induction, but the alleviation mechanism of the detailed FA function against NO has not yet been clarified. This study focused on elucidation of the interaction of FA and [...] Read more.

Folic acid (FA) can be protected the neural tube defects (NTDs) causing nitric oxide (NO) induction, but the alleviation mechanism of the detailed FA function against NO has not yet been clarified. This study focused on elucidation of the interaction of FA and NO. FA suppressed nitrite accumulation as the NO indicator in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, then the expression of the iNOS gene due to the LPS treatment was not inhibited by FA, suggesting that FA can modulate against NO or nitrogen radicals. NOR3 (4-ethyl-2-hydroxyamino-5-nitro-3-hexenamide) as the NO donor was used for evaluation of the NO scavenging activity of FA. FA suppressed the nitrite accumulation in a dose-dependent manner. To confirm the reaction product of FA and NO (FA-NO), liquid chromatography–mass spectrometry (LC/MS) was used to measure a similar system containing NOR3 and FA, and then detected the mass numbers of the FA-NO as m/z 470.9 (M + H)⁺ and m/z 469.1 (M − H)⁻. In addition, the adducts of the FA-NO derived from ¹⁴NO and ¹⁵NO gave individual mass numbers of the isotopic ratio of nitrogen for the following products: FA-¹⁴NO, m/z 471.14 (M + H)⁺; m/z 469.17 (M − H)⁻ and FA-¹⁵NO, m/z 472.16 (M + H)⁺; m/z 470.12 (M − H)^–. To clarify the detailed NO scavenging action of FA, an electron spin resonance (ESR) study for radical detecting of the system containing carboxy-PTIO (2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) as an NO detection reagent in the presence of NOR3 and FA was performed. The carboxy-PTI (2-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl) radical produced from the reaction with NO reduced in the presence of FA showing that FA can directly scavenge NO. These results indicated that NO scavenging activity of FA reduced the accumulation of nitrite in the LPS-stimulated RAW264.7 cells. The NO modulation due to FA would be responsible for the alleviation from the failure in neural tube formation causing a high level of NO production. Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

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15 pages, 5309 KiB

Open AccessArticle

Human Keratinocyte UVB-Protective Effects of a Low Molecular Weight Fucoidan from Sargassum horneri Purified by Step Gradient Ethanol Precipitation

by Ilekuttige Priyan Shanura Fernando, Mawalle Kankanamge Hasitha Madhawa Dias, Disanayaka Mudiyanselage Dinesh Madusanka, Eui Jeong Han, Min Ju Kim, You-Jin Jeon, Kyounghoon Lee, Sun Hee Cheong, Young Seok Han, Sang Rul Park and Ginnae Ahn

Antioxidants 2020, 9(4), 340; https://doi.org/10.3390/antiox9040340 - 21 Apr 2020

Cited by 33 | Viewed by 5410

Abstract

Ultraviolet B (UVB) radiation-induced oxidative skin cell damage is a major cause of photoaging. In the present study, a low molecular weight fucoidan fraction (SHC4) was obtained from Sargassum horneri by Celluclast-assisted extraction, followed by step gradient ethanol precipitation. The protective effect of [...] Read more.

Ultraviolet B (UVB) radiation-induced oxidative skin cell damage is a major cause of photoaging. In the present study, a low molecular weight fucoidan fraction (SHC4) was obtained from Sargassum horneri by Celluclast-assisted extraction, followed by step gradient ethanol precipitation. The protective effect of SHC4 was investigated in human keratinocytes against UVB-induced oxidative stress. The purified fucoidan was characterized by Fourier-transform infrared spectroscopy (FTIR), ¹H nuclear magnetic resonance (NMR), agarose gel-based molecular weight analysis and monosaccharide composition analysis. SHC4 had a mean molecular weight of 60 kDa, with 37.43% fucose and 28.01 ± 0.50% sulfate content. The structure was mainly composed of α-L-Fucp-(1→4) linked fucose units. SHC4 treatment dose-dependently reduced intracellular reactive oxygen species (ROS) levels and increased the cell viability of UVB exposed HaCaT keratinocytes. Moreover, SHC4 dose-dependently inhibited UVB-induced apoptotic body formation, sub-G₁ accumulation of cells and DNA damage. Inhibition of apoptosis was mediated via the mitochondria-mediated pathway, re-establishing the loss of mitochondrial membrane potential. The UVB protective effect of SHC4 was facilitated by enhancing intracellular antioxidant defense via nuclear factor erythroid 2–related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling. Further studies may promote the use of SHC4 as an active ingredient in cosmetics and nutricosmetics. Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

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14 pages, 2732 KiB

Open AccessArticle

Computational Study of Ortho-Substituent Effects on Antioxidant Activities of Phenolic Dendritic Antioxidants

by Choon Young Lee, Ajit Sharma, Julius Semenya, Charles Anamoah, Kelli N. Chapman and Veronica Barone

Antioxidants 2020, 9(3), 189; https://doi.org/10.3390/antiox9030189 - 25 Feb 2020

Cited by 51 | Viewed by 5114

Abstract

Antioxidants are an important component of our ability to combat free radicals, an excess of which leads to oxidative stress that is related to aging and numerous human diseases. Oxidative damage also shortens the shelf-life of foods and other commodities. Understanding the structure–activity [...] Read more.

Antioxidants are an important component of our ability to combat free radicals, an excess of which leads to oxidative stress that is related to aging and numerous human diseases. Oxidative damage also shortens the shelf-life of foods and other commodities. Understanding the structure–activity relationship of antioxidants and their mechanisms of action is important for designing more potent antioxidants for potential use as therapeutic agents as well as preservatives. We report the first computational study on the electronic effects of ortho-substituents in dendritic tri-phenolic antioxidants, comprising a common phenol moiety and two other phenol units with electron-donating or electron-withdrawing substituents. Among the three proposed antioxidant mechanisms, sequential proton loss electron transfer (SPLET) was found to be the preferred mechanism in methanol for the dendritic antioxidants based on calculations using Gaussian 16. We then computed the total enthalpy values by cumulatively running SPLET for all three rings to estimate electronic effects of substituents on overall antioxidant activity of each dendritic antioxidant and establish their structure–activity relationships. Our results show that the electron-donating o-OCH₃ group has a beneficial effect while the electron-withdrawing o-NO₂ group has a negative effect on the antioxidant activity of the dendritic antioxidant. The o-Br and o-Cl groups did not show any appreciable effects. These results indicate that electron-donating groups such as o-methoxy are useful for designing potent dendritic antioxidants while the nitro and halogens do not add value to the radical scavenging antioxidant activity. We also found that the half-maximal inhibitory concentration (IC50) values of 2,2-diphenyl-1-picrylhydrazyl (DPPH) better correlate with the second step (electron transfer enthalpy, ETE) than the first step (proton affinity, PA) of the SPLET mechanism, implying that ETE is the better measure for estimating overall radical scavenging antioxidant activities. Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

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15 pages, 1712 KiB

Open AccessArticle

The Effect of Nano-Epigallocatechin-Gallate on Oxidative Stress and Matrix Metalloproteinases in Experimental Diabetes Mellitus

by Adriana Elena Bulboaca, Paul-Mihai Boarescu, Alina Silvia Porfire, Gabriela Dogaru, Cristina Barbalata, Madalina Valeanu, Constantin Munteanu, Ruxandra Mioara Râjnoveanu, Cristina Ariadna Nicula and Ioana Cristina Stanescu

Antioxidants 2020, 9(2), 172; https://doi.org/10.3390/antiox9020172 - 20 Feb 2020

Cited by 29 | Viewed by 5239

Abstract

Background: The antioxidant properties of epigallocatechin-gallate (EGCG), a green tea compound, have been already studied in various diseases. Improving the bioavailability of EGCG by nanoformulation may contribute to a more effective treatment of diabetes mellitus (DM) metabolic consequences and vascular complications. The aim [...] Read more.

Background: The antioxidant properties of epigallocatechin-gallate (EGCG), a green tea compound, have been already studied in various diseases. Improving the bioavailability of EGCG by nanoformulation may contribute to a more effective treatment of diabetes mellitus (DM) metabolic consequences and vascular complications. The aim of this study was to test the comparative effect of liposomal EGCG with EGCG solution in experimental DM induced by streptozotocin (STZ) in rats. Method: 28 Wistar-Bratislava rats were randomly divided into four groups (7 animals/group): group 1—control group, with intraperitoneal (i.p.) administration of 1 mL saline solution (C); group 2—STZ administration by i.p. route (60 mg/100 g body weight, bw) (STZ); group 3—STZ administration as before + i.p. administration of EGCG solution (EGCG), 2.5 mg/100 g b.w. as pretreatment; group 4—STZ administration as before + i.p. administration of liposomal EGCG, 2.5 mg/100 g b.w. (L-EGCG). The comparative effects of EGCG and L-EGCG were studied on: (i) oxidative stress parameters such as malondialdehyde (MDA), indirect nitric oxide (NOx) synthesis, and total oxidative status (TOS); (ii) antioxidant status assessed by total antioxidant capacity of plasma (TAC), thiols, and catalase; (iii) matrix-metalloproteinase-2 (MMP-2) and -9 (MMP-9). Results: L-EGCG has a better efficiency regarding the improvement of oxidative stress parameters (highly statistically significant with p-values < 0.001 for MDA, NOx, and TOS) and for antioxidant capacity of plasma (highly significant p < 0.001 for thiols and significant for catalase and TAC with p < 0.05). MMP-2 and -9 were also significantly reduced in the L-EGCG-treated group compared with the EGCG group (p < 0.001). Conclusions: the liposomal nanoformulation of EGCG may serve as an adjuvant therapy in DM due to its unique modulatory effect on oxidative stress/antioxidant biomarkers and MMP-2 and -9. Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

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16 pages, 3497 KiB

Open AccessArticle

A Novel Pectic Polysaccharide of Jujube Pomace: Structural Analysis and Intracellular Antioxidant Activities

by Ximeng Lin, Keshan Liu, Sheng Yin, Yimin Qin, Peili Shen and Qiang Peng

Antioxidants 2020, 9(2), 127; https://doi.org/10.3390/antiox9020127 - 2 Feb 2020

Cited by 26 | Viewed by 3405

Abstract

After extraction from jujube pomace and purification by two columns (DEAE-Sepharose Fast Flow and Sepharcyl S-300), the structure of SAZMP4 was investigated by HPGPC, GC, FI-IR, GC-MS, NMR, SEM, and AFM. Analysis determined that SAZMP4 (Mw = 28.94 kDa) was a pectic polysaccharide [...] Read more.

After extraction from jujube pomace and purification by two columns (DEAE-Sepharose Fast Flow and Sepharcyl S-300), the structure of SAZMP4 was investigated by HPGPC, GC, FI-IR, GC-MS, NMR, SEM, and AFM. Analysis determined that SAZMP4 (Mw = 28.94 kDa) was a pectic polysaccharide mainly containing 1,4-linked GalA (93.48%) with side chains of 1,2,4-linked Rha and 1,3,5-linked Ara and terminals of 1-linked Rha and 1-linked Ara, which might be the homogalacturonan (HG) type with side chains of the RG-I type, corresponding to the results of NMR. In AFM and SEM images, self-assembly and aggregation of SAZMP4 were respectively observed indicating its structural features. The antioxidant activity of SAZMP4 against H₂O₂-induced oxidative stress in Caco-2 cells was determined by activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) as well as malondialdehyde (MDA) and reactive oxygen species (ROS) levels, indicating SAZMP4 can be a natural antioxidant. Also, a better water retention capacity and thermal stability of SAZMP4 was observed based on DSC analysis, which could be applied in food industry as an additive. Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

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10 pages, 1428 KiB

Open AccessArticle

Induction of Antioxidant Protein HO-1 Through Nrf2-ARE Signaling Due to Pteryxin in Peucedanum Japonicum Thunb in RAW264.7 Macrophage Cells

by Junsei Taira and Takayuki Ogi

Antioxidants 2019, 8(12), 621; https://doi.org/10.3390/antiox8120621 - 5 Dec 2019

Cited by 23 | Viewed by 4940

Abstract

This study focused on exploring the nuclear factor-erythroid-2-related factor (Nrf2) active compound to avoid oxidative stress related to various diseases, such as obesity and diabetes mellitus. The activity of the Nrf2-ARE (antioxidant response element) signaling was evaluated by a reporter assay involving over [...] Read more.

This study focused on exploring the nuclear factor-erythroid-2-related factor (Nrf2) active compound to avoid oxidative stress related to various diseases, such as obesity and diabetes mellitus. The activity of the Nrf2-ARE (antioxidant response element) signaling was evaluated by a reporter assay involving over five hundred various edible medicinal herbs, and the highest Nrf2 activity was found in the ethanol extract of Peucedanum japonicum leaves. The active compound in the extract was isolated by high performance liquid chromatography (HPLC), and the chemical structure was identical to pteryxin based on ¹H, ¹³C-NMR spectra and liquid chromatography/time-of-fright mass spectrometer (LC/TOF/MS). From the pteryxin, the transcription factor Nrf2 was accumulated in the nucleus and resulted in the expression of the antioxidant protein, heme oxygenase-1 (HO-1). In addition, the Nrf2 activity involving HO-1 expression due to coumarin derivatives was evaluated together with pteryxin. This suggested that the electrophilicity, due to the α,β-carbonyl and/or substituted acyl groups in the molecule, modulates the cysteine residue in Keap1 via the Michel reaction, at which point the Nrf2 is dissociated from the Keap1. These results suggest that pteryxin will be a useful agent for developing functional foods. Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

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12 pages, 991 KiB

Open AccessArticle

Protective Effect of Tomato-Oleoresin Supplementation on Oxidative Injury Recoveries Cardiac Function by Improving β-Adrenergic Response in a Diet-Obesity Induced Model

by Artur Junio Togneri Ferron, Giancarlo Aldini, Fabiane Valentini Francisqueti-Ferron, Carol Cristina Vágula de Almeida Silva, Silmeia Garcia Zanati Bazan, Jéssica Leite Garcia, Dijon Henrique Salomé de Campos, Luciana Ghiraldeli, Koody Andre Hassemi Kitawara, Alessandra Altomare, Camila Renata Correa, Fernando Moreto and Ana Lucia A. Ferreira

Antioxidants 2019, 8(9), 368; https://doi.org/10.3390/antiox8090368 - 2 Sep 2019

Cited by 16 | Viewed by 3198

Abstract

The system redox imbalance is one of the pathways related to obesity-related cardiac dysfunction. Lycopene is considered one of the best antioxidants. The aim of this study was to test if the tomato-oleoresin would be able to recovery cardiac function by improving β-adrenergic [...] Read more.

The system redox imbalance is one of the pathways related to obesity-related cardiac dysfunction. Lycopene is considered one of the best antioxidants. The aim of this study was to test if the tomato-oleoresin would be able to recovery cardiac function by improving β-adrenergic response due its antioxidant effect. A total of 40 animals were randomly divided into two experimental groups to receive either the control diet (Control, n = 20) or a high sugar-fat diet (HSF, n = 20) for 20 weeks. Once cardiac dysfunction was detected by echocardiogram in the HSF group, animals were re- divided to begin the treatment with Tomato-oleoresin or vehicle, performing four groups: Control (n = 6); (Control + Ly, n = 6); HSF (n = 6) and (HSF + Ly, n = 6). Tomato oleoresin (10 mg lycopene/kg body weight (BW) per day) was given orally every morning for a 10-week period. The analysis included nutritional and plasma biochemical parameters, systolic blood pressure, oxidative parameters in plasma, heart, and cardiac analyses in vivo and in vitro. A comparison among the groups was performed by two-way analysis of variance (ANOVA). Results: The HSF diet was able to induce obesity, insulin-resistance, cardiac dysfunction, and oxidative damage. However, the tomato-oleoresin supplementation improved insulin-resistance, cardiac remodeling, and dysfunction by improving the β-adrenergic response. It is possible to conclude that tomato-oleoresin is able to reduce the oxidative damage by improving the system’s β-adrenergic response, thus recovering cardiac function. Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

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23 pages, 825 KiB

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Dietary Antioxidants and Parkinson’s Disease

by Han-A Park and Amy C. Ellis

Antioxidants 2020, 9(7), 570; https://doi.org/10.3390/antiox9070570 - 1 Jul 2020

Cited by 54 | Viewed by 10996

Abstract

Parkinson’s disease (PD) is a neurodegenerative disorder caused by the depletion of dopaminergic neurons in the basal ganglia, the movement center of the brain. Approximately 60,000 people are diagnosed with PD in the United States each year. Although the direct cause of PD [...] Read more.

Parkinson’s disease (PD) is a neurodegenerative disorder caused by the depletion of dopaminergic neurons in the basal ganglia, the movement center of the brain. Approximately 60,000 people are diagnosed with PD in the United States each year. Although the direct cause of PD can vary, accumulation of oxidative stress-induced neuronal damage due to increased production of reactive oxygen species (ROS) or impaired intracellular antioxidant defenses invariably occurs at the cellular levels. Pharmaceuticals such as dopaminergic prodrugs and agonists can alleviate some of the symptoms of PD. Currently, however, there is no treatment to halt the progression of PD pathology. Due to the nature of PD, a long and progressive neurodegenerative process, strategies to prevent or delay PD pathology may be well suited to lifestyle changes like dietary modification with antioxidant-rich foods to improve intracellular redox homeostasis. In this review, we discuss cellular and genetic factors that increase oxidative stress in PD. We also discuss neuroprotective roles of dietary antioxidants including vitamin C, vitamin E, carotenoids, selenium, and polyphenols along with their potential mechanisms to alleviate PD pathology. Full article

(This article belongs to the Special Issue Oxidative Stress Modulators and Functional Foods)

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