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1.
World J Urol ; 42(1): 425, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037613

RESUMO

OBJECTIVES: This study was to investigate the correlation between oxidative balance score (OBS) and the prevalence of kidney stones in the general adult population. MATERIALS AND METHODS: We conducted an analysis using data from the 2007-2018 National Health and Nutrition Examination Survey (NHANES) project, including 17,988 participants. The OBS was computed based on previous research, combining 16 dietary factors and 4 lifestyle factors. Multiple logistic regressions and restricted cubic spline (RCS) regressions were utilized to explore the associations between OBS and kidney stone prevalence. RESULTS: Our analysis included 1,622 adults with kidney stones and 16,366 adults without kidney stones. The average age of participants was 46.86 ± 0.27 years, with 50.72% being male. The median OBS was 22.00 (17.00, 27.00). After adjusting for all covariates, each one-unit increase in OBS was associated with a 3% decrease in kidney stone prevalence (odds ratio [OR] = 0.97 [0.96-0.98], P < 0.001). Moreover, compared to the first quartile, the fourth quartile of OBS (OR = 0.65 [0.50-0.84], P = 0.001) exhibited a negative association with kidney stone prevalence after adjusting for multiple variables. Furthermore, we observed a non-linear negative relationship between OBS and kidney stone prevalence, with inflection points at 18.2 (P for nonlinearity = 0.048). Stratified analysis did not identify any variables significantly affecting the results. CONCLUSION: Our findings indicate that a higher OBS is associated with a decreased prevalence of kidney stones in the general adult population.


Assuntos
Cálculos Renais , Humanos , Cálculos Renais/epidemiologia , Cálculos Renais/metabolismo , Cálculos Renais/química , Masculino , Feminino , Pessoa de Meia-Idade , Prevalência , Adulto , Estresse Oxidativo , Inquéritos Nutricionais , Estudos Transversais
2.
Cancer Immunol Immunother ; 72(3): 527-542, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36066649

RESUMO

Neutrophils have recently gained recognition for their potential in the fight against cancer. Neutrophil plasticity between the N1 anti-tumor and N2 pro-tumor subtypes is now apparent, as is the ability to polarize these individual subtypes by interventions such as intratumoral injection of various agents including bacterial products or pro-oxidants. Metabolic responses and the production of reactive oxygen species (ROS) such as hydrogen peroxide act as potent chemoattractants and activators of N1 neutrophils that facilitates their recruitment and ensuing activation of a toxic respiratory burst in tumors. Greater understanding of the precise mechanism of N1 neutrophil activation, recruitment and regulation is now needed to fully exploit their anti-tumor potential against cancers both locally and at distant sites. This systematic review critically analyzes these new developments in cancer immunotherapy.


Assuntos
Neoplasias , Neutrófilos , Humanos , Espécies Reativas de Oxigênio/metabolismo , Neutrófilos/metabolismo , Explosão Respiratória , Imunoterapia , Neoplasias/metabolismo
3.
Molecules ; 28(11)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37298962

RESUMO

In women, breast cancer is the most commonly diagnosed cancer (11.7% of total cases) and the leading cause of cancer death (6.9%) worldwide. Bioactive dietary components such as Sea buckthorn berries are known for their high carotenoid content, which has been shown to possess anti-cancer properties. Considering the limited number of studies investigating the bioactive properties of carotenoids in breast cancer, the aim of this study was to investigate the antiproliferative, antioxidant, and proapoptotic properties of saponified lipophilic Sea buckthorn berries extract (LSBE) in two breast cancer cell lines with different phenotypes: T47D (ER+, PR+, HER2-) and BT-549 (ER-, PR-, HER2-). The antiproliferative effects of LSBE were evaluated by an Alamar Blue assay, the extracellular antioxidant capacity was evaluated through DPPH, ABTS, and FRAP assays, the intracellular antioxidant capacity was evaluated through a DCFDA assay, and the apoptosis rate was assessed by flow cytometry. LSBE inhibited the proliferation of breast cancer cells in a concentration-dependent manner, with a mean IC50 of 16 µM. LSBE has proven to be a good antioxidant both at the intracellular level, due to its ability to significantly decrease the ROS levels in both cell lines (p = 0.0279 for T47D, and p = 0.0188 for BT-549), and at the extracellular level, where the ABTS and DPPH inhibition vried between 3.38-56.8%, respectively 5.68-68.65%, and 35.6 mg/L equivalent ascorbic acid/g LSBE were recorded. Based on the results from the antioxidant assays, LSBE was found to have good antioxidant activity due to its rich carotenoid content. The flow cytometry results revealed that LSBE treatment induced significant alterations in late-stage apoptotic cells represented by 80.29% of T47D cells (p = 0.0119), and 40.6% of BT-549 cells (p = 0.0137). Considering the antiproliferative, antioxidant, and proapoptotic properties of the carotenoids from LSBE on breast cancer cells, further studies should investigate whether these bioactive dietary compounds could be used as nutraceuticals in breast cancer therapy.


Assuntos
Hippophae , Neoplasias , Humanos , Antioxidantes/química , Carotenoides/química , Hippophae/química , Células MCF-7 , Frutas/química , Extratos Vegetais/química
4.
Angew Chem Int Ed Engl ; 62(27): e202302463, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37144706

RESUMO

Ascorbate (H2 A) is a well-known antioxidant to protect cellular components from free radical damage and has also emerged as a pro-oxidant in cancer therapies. However, such "contradictory" mechanisms underlying H2 A oxidation are not well understood. Herein, we report Fe leaching during catalytic H2 A oxidation using an Fe-N-C nanozyme as a ferritin mimic and its influence on the selectivity of the oxygen reduction reaction (ORR). Owing to the heterogeneity, the Fe-Nx sites in Fe-N-C primarily catalyzed H2 A oxidation and 4 e- ORR via an iron-oxo intermediate. Nonetheless, trace O2 ⋅- produced by marginal N-C sites through 2 e- ORR accumulated and attacked Fe-Nx sites, leading to the linear leakage of unstable Fe ions up to 420 ppb when the H2 A concentration increased to 2 mM. As a result, a substantial fraction (ca. 40 %) of the N-C sites on Fe-N-C were activated, and a new 2+2 e- ORR path was finally enabled, along with Fenton-type H2 A oxidation. Consequently, after Fe ions diffused into the bulk solution, the ORR at the N-C sites stopped at H2 O2 production, which was the origin of the pro-oxidant effect of H2 A.

5.
Int J Mol Sci ; 23(14)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35887292

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease characterized by parenchymal scarring, leading progressively to alveolar architecture distortion, respiratory failure, and eventually death. Currently, there is no effective treatment for IPF. Previously, 3'5-dimaleamylbenzoic acid (3'5-DMBA), a maleimide, demonstrated pro-apoptotic, anti-inflammatory, and anti-cancer properties; however, its potential therapeutic effects on IPF have not been addressed. Bleomycin (BLM) 100 U/kg was administered to CD1 mice through an osmotic minipump. After fourteen days of BLM administration, 3'5-DMBA (6 mg/kg or 10 mg/kg) and its vehicle carboxymethylcellulose (CMC) were administered intragastrically every two days until day 26. On day 28, all mice were euthanized. The 3'5-DMBA effect was assessed by histological and immunohistochemical staining, as well as by RT-qPCR. The redox status on lung tissue was evaluated by determining the glutathione content and the GSH/GSSG ratio. 3'5-DMBA treatment re-established typical lung histological features and decreased the expression of BLM-induced fibrotic markers: collagen, α-SMA, and TGF-ß1. Furthermore, 3'5-DMBA significantly reduced the expression of genes involved in fibrogenesis. In addition, it decreased reduced glutathione and increased oxidized glutathione content without promoting oxidative damage to lipids, as evidenced by the decrease in the lipid peroxidation marker 4-HNE. Therefore, 3'5-DMBA may be a promising candidate for IPF treatment.


Assuntos
Bleomicina , Fibrose Pulmonar Idiopática , Animais , Anti-Inflamatórios/farmacologia , Bleomicina/efeitos adversos , Colágeno/metabolismo , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Fator de Crescimento Transformador beta1/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-34004319

RESUMO

To understand foraging strategies and behavioral flexibility in wild animals, it is important to evaluate the physiological costs imposed by foraging efforts and how these costs affect foraging and provisioning behavior. Oxidative stress is a possible physiological indicator associated with foraging behavior in wild seabirds, and may also affect their reproductive performance. However, no previous study has simultaneously recorded foraging behavior and the associated oxidative stress in wild seabirds. Using an integrative approach based on oxidative stress measurements and bio-logging techniques (i.e., the use of animal-borne sensors), we determined the relationships between foraging behavior and oxidative stress in chick-rearing streaked shearwaters Calonectris leucomelas in 2018 and 2019. To quantify their oxidative stress, we measured reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP) in their plasma. We found that the d-ROMs levels were positively related to the maximum distance from the colony and the number of takeoffs, especially in 2019 when shearwaters flew further to forage. In 2018, when they flew relatively short distances, the BAP levels were positively related to the levels of their physical activity (overall dynamic body acceleration; ODBA). We conclude that longer and less successful foraging may lead to increase oxidative stress, while successful foraging may mitigate the oxidative stress of foraging by providing dietary antioxidants. Our results highlight that the combined data from bio-logging and oxidative stress measurements aid in evaluating the underlying physiological costs of foraging behavior in wild animals.


Assuntos
Aves/fisiologia , Comportamento Alimentar/fisiologia , Estresse Oxidativo , Ração Animal , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Comportamento Animal , Feminino , Geografia , Masculino , Oxidantes/farmacologia , Temperatura
7.
Cancer Metastasis Rev ; 38(1-2): 189-203, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30820778

RESUMO

In cancer, mitochondrial functions are commonly altered. Directly involved in metabolic reprogramming, mitochondrial plasticity confers to cancer cells a high degree of adaptability to a wide range of stresses and to the harsh tumor microenvironment. Lack of nutrients or oxygen caused by altered perfusion, metabolic needs of proliferating cells, co-option of the microenvironment, control of the immune system, cell migration and metastasis, and evasion of exogenous stress (e.g., chemotherapy) are all, at least in part, influenced by mitochondria. Mitochondria are undoubtedly one of the key contributors to cancer development and progression. Understanding their protumoral (dys)functions may pave the way to therapeutic strategies capable of turning them into innocent entities. Here, we will focus on the production and detoxification of mitochondrial reactive oxygen species (mtROS), on their impact on tumorigenesis (genetic, prosurvival, and microenvironmental effects and their involvement in autophagy), and on tumor metastasis. We will also summarize the latest therapeutic approaches involving mtROS.


Assuntos
Mitocôndrias/metabolismo , Neoplasias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Antioxidantes/metabolismo , Carcinogênese/metabolismo , Carcinogênese/patologia , Humanos , Mitocôndrias/patologia , Neoplasias/patologia , Fosforilação Oxidativa
8.
Mutagenesis ; 35(6): 479-489, 2020 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-33259605

RESUMO

In this study, we have studied the cytotoxicity and genotoxic potency of 3 pro-oxidants; H2O2, menadione and KBrO3 in different dosing scenarios, namely acute (1-day dosing) and chronic (5-days). For this purpose, relative population doubling (RPD%) and mononucleated micronucleus (MN) test were used. TK6 cells and NH32 were employed in in vitro experiments. In the study, the total acute dose was divided into 5 days for each prooxidant chemicals by dose fractionation (1/5th per day) method. Acute dosing was compared to chronic dosing. The oxidative stress caused by the exposure of cells with pro-oxidant chemicals to the cells was determined by an optimized 2',7'-dichlorofluorescein diacetate (DCFHDA) test method. The antioxidant levels of the cell lines were altered with buthionine sulfoxide (BSO) and N-acetyl cysteine (NAC), and the effect of antioxidant capacity on the MN formation in the cells was observed with this method. In the case of H2O2 and menadione, fractional dosing has been observed to result in lower toxicity and lower genotoxicity. But in the case of KBrO3, unlike the other 2 pro-oxidants, higher MN induction was observed with fractionated doses. DCFHDA test clearly demonstrated ROS induction with H2O2 and menadione but not with KBrO3. Unexpectedly, DCFHDA test demonstrated that KBrO3 did not cause an increase ROS levels in both acute and chronic dosing, suggesting an alternative ROS induction mechanism. It was also observed that, treatment with BSO and NAC, caused increasing and decreasing of MN fold change respectively, allowing further ROS specific mechanisms to be explored. Hence, dose fractionation expectedly caused less MN, cytotoxicity and ROS formation with H2O2 and menadione exposure, but not with KBrO3. This implies a unique mechanism of action for KBrO3 induced genotoxicity. Chronic dosing in vitro may be a valuable approach allowing better understanding of how chemicals damage DNA and pose human hazards.


Assuntos
Dano ao DNA/efeitos dos fármacos , Testes de Mutagenicidade/métodos , Mutagênicos/administração & dosagem , Oxidantes/administração & dosagem , Proteína Supressora de Tumor p53/genética , Linhagem Celular , Células Cultivadas , Resistência a Medicamentos/genética , Glutationa/metabolismo , Humanos , Peróxido de Hidrogênio/administração & dosagem , Peróxido de Hidrogênio/toxicidade , Testes para Micronúcleos/métodos , Mutagênicos/toxicidade , Oxidantes/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/deficiência , Vitamina K 3/metabolismo
9.
J Allergy Clin Immunol ; 144(6): 1534-1541.e5, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31437488

RESUMO

BACKGROUND: Fetal oxidative balance (achieved when protective prenatal factors counteract sources of oxidative stress) might be critical for preventing asthma and allergic disease. OBJECTIVE: We examined prenatal intakes of hypothesized protective nutrients (including antioxidants) in conjunction with potential sources of oxidative stress in models of adolescent asthma and allergic disease. METHODS: We used data from 996 mother-child pairs in Project Viva. Exposures of interest were maternal prepregnancy body mass index and prenatal nutrients (energy-adjusted intakes of vitamins D, C, and E; ß-carotene; folate; choline; and n-3 and n-6 polyunsaturated fatty acids [PUFAs]), air pollutant exposures (residence-specific third-trimester black carbon or particulate matter with a diameter of less than 2.5 µm [PM2.5]), acetaminophen, and smoking. Outcomes were offspring's current asthma, allergic rhinitis, and allergen sensitization at a median age of 12.9 years. We performed logistic regression. Continuous exposures were log-transformed and modeled as z scores. RESULTS: We observed protective associations for vitamin D (odds ratio [OR], 0.69 [95% CI, 0.53-0.89] for allergic rhinitis), the sum of the n-3 PUFAs eicosapentaenoic acid and docosahexaenoic acid (OR, 0.81 [95% CI, 0.66-0.99] for current asthma), and the n-3 PUFA α-linolenic acid (OR, 0.78 [95% CI, 0.64-0.95] for allergen sensitization and OR, 0.80 [95% CI 0.65-0.99] for current asthma). Black carbon and PM2.5 were associated with an approximately 30% increased risk for allergen sensitization. No multiplicative interactions were observed for protective nutrient intakes with sources of oxidative stress. CONCLUSIONS: We identified potential protective prenatal nutrients (vitamin D and n-3 PUFAs), as well as adverse prenatal pro-oxidant exposures that might alter the risk of asthma and allergic disease into adolescence.


Assuntos
Asma/sangue , Ácidos Graxos Ômega-3/sangue , Estresse Oxidativo , Terceiro Trimestre da Gravidez/sangue , Efeitos Tardios da Exposição Pré-Natal/sangue , Rinite Alérgica/sangue , Vitamina D/sangue , Adolescente , Asma/etiologia , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez , Rinite Alérgica/etiologia
10.
Semin Cancer Biol ; 46: 1-13, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28511887

RESUMO

Cancer prevention can be probably obtained with easier, faster and less financial strains by pursuing educational programs aimed to induce changes in lifestyle, starting from dietary habits. In the past decades, observational and case-control studies tried to establish a functional relationship between cancer mortality and morbidity and diet. The field becomes even more intricate when scientists investigated which dietary components are responsible for the putative, protective effects of fruits and vegetables against cancer. A relevant part of the literature focused on the positive role of "antioxidant" compounds in foods, including polyphenols. The present review critically evaluate clinical and pre-clinical studies based on polyphenol administration, which contributed to support the concept, deeply rooted in the general population, that antioxidant polyphenols can fight cancer. The controversial and contradictory issues related to the pros and cons on the use of polyphenols against cancer reflect the confounding assumption that cancer treatment and cancer prevention may overlap. We conclude that a clear cut must be done between these two concepts and that the experimental approaches to investigate one or the other should be significantly different, starting from adequate and specifically selected cellular models.


Assuntos
Antioxidantes/uso terapêutico , Neoplasias/dietoterapia , Polifenóis/uso terapêutico , Humanos , Neoplasias/epidemiologia
11.
Arch Toxicol ; 92(2): 745-757, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29098328

RESUMO

Beside the key inhibition of acetylcholinesterase (AChE), involvement of oxidative stress in organophosphate (OP)-induced toxicity has been supported by experimental and human studies. On the other hand, according to our best knowledge, possible antioxidant properties of oximes, the only causal antidotes to OP-inhibited AChE, have been examined only by a few studies. Thus, we have determined the effect of four conventional (obidoxime, trimedoxime, pralidoxime, asoxime) and two promising experimental oximes (K027, K203) on dichlorvos (DDVP)-induced oxidative changes in vivo. Wistar rats (5/group) were treated with oxime (5% LD50 i.m) immediately after DDVP challenge (75% LD50 s.c). Oxidative stress biomarkers were determined in plasma and brain 60 min after the treatment: prooxidative-superoxide anion (O2·-) and total oxidative status (TOS); antioxidative-superoxide dismutase (SOD), total thiol (SH) groups, total antioxidant status (TAS) and paraoxonase (PON1); tissue oxidative stress burden-prooxidative-antioxidative balance (PAB) and oxidative stress index (OSI); oxidative tissue damage-malondialdehyde (MDA) and advanced oxidation protein products (AOPP). All oximes were able to attenuate DDVP-induced oxidative stress in rat plasma and brain. Changes of determined parameters in brain were not as prominent as it was seen in plasma. Based on OSI, better abilities of oxime K027, K203 and obidoxime to maintain DDVP-induced oxidative stress in rat brain were shown as compared to trimedoxime, pralidoxime and asoxime. Oximes can influence the complex in vivo redox processes that might contribute to their overall therapeutic efficacy. Further research is needed to understand the underlying molecular mechanisms involved in this phenomenon.


Assuntos
Encéfalo/efeitos dos fármacos , Inibidores da Colinesterase/farmacologia , Diclorvós/toxicidade , Intoxicação por Organofosfatos/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Oximas/farmacologia , Animais , Arildialquilfosfatase/sangue , Biomarcadores/sangue , Masculino , Malondialdeído/sangue , Cloreto de Obidoxima/farmacologia , Compostos de Pralidoxima , Compostos de Piridínio/farmacologia , Ratos , Superóxido Dismutase/sangue , Trimedoxima/farmacologia
12.
Artigo em Inglês | MEDLINE | ID: mdl-29410189

RESUMO

The maternal allocation of carotenoids to eggs has been widely documented and manipulated. However, it is often assumed that the sole adaptive value of this allocation is to increase offspring fitness. Because carotenoids can be pro-oxidants or antioxidants depending on their concentrations and their chemical environment (i.e. presence of other antioxidants), dams may need to dispose of excess carotenoids upon depletion of other antioxidants to prevent oxidative damage. Additionally, the amount of carotenoids deposited in eggs may be dependent on male traits such as quality and coloration. We evaluated these two non-mutually exclusive hypotheses for carotenoid allocation to eggs and assessed paternal effects by supplementing male and female brown anole lizards, Anolis sagrei, with dietary carotenoids or with a combination of carotenoids and vitamin C. We found significant differences in the antioxidant capacities of fertilized and unfertilized eggs produced by female lizards, but the treatment did not affect the antioxidant capacity or carotenoid content of eggs. However, the carotenoid concentration of unfertilized eggs from carotenoid-supplemented females was significantly higher than eggs from the control group. Male coloration and body size did not affect the antioxidant capacity or carotenoid content of the eggs. Carotenoids may be allocated to unfertilized eggs to offset oxidative damage to the dam, with a neutral effect on offspring, rather than to solely provide antioxidant benefits to offspring as has been widely assumed.


Assuntos
Carotenoides/metabolismo , Lagartos/fisiologia , Comportamento Materno , Óvulo/metabolismo , Animais , Tamanho Corporal , Cor , Feminino , Masculino , Estresse Oxidativo , Zigoto/metabolismo
13.
J Obstet Gynaecol Res ; 44(3): 509-517, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29239072

RESUMO

AIM: The main goal of this work was to highlight the significance of redox imbalance in the pathophysiology of bacterial vaginosis (BV). We studied the pro-oxidant (malondialdehyde) and antioxidants (glutathione, total antioxidant capacity) in the vaginal fluids of women and compared them on the basis of their Nugent score (NS). METHODS: Women were clinically screened using Amsel criteria (≥2 were regarded as positive) and were further screened for NS on the basis of microscopic examination. Subjects were classified into one of three groups - healthy controls, intermediate, and BV - on the basis of NS (0-3, 4-6, and 7-10, respectively). High vaginal swabs were collected from the study participants in order to estimate the levels of pro and antioxidants in the vaginal fluids. RESULTS: Our results indicated that levels of both pro- and antioxidants were elevated in high vaginal swabs of women in the intermediate (NS: 4-6) and BV (NS: 7-10) groups as compared to those of healthy control women. The difference in mean values for total antioxidant capacity and glutathione was found to be statistically significant. Furthermore, in the BV group (NS: ≥7) both antioxidants (glutathione and total antioxidant capacity) and the pro-oxidant, malondialdehyde, were found to be negatively correlated to NS. Interestingly, the correlation between NS and malondialdehyde was statistically significant. CONCLUSION: Our results suggest a significant correlation between redox imbalance and NS, which signifies changes in vaginal ecology from normal flora (Lactobacillus spp.) towards a more mixed bacterial population representing BV.


Assuntos
Oxirredução , Vagina , Vaginose Bacteriana , Adulto , Feminino , Humanos , Vagina/diagnóstico por imagem , Vagina/metabolismo , Vagina/microbiologia , Vaginose Bacteriana/diagnóstico , Vaginose Bacteriana/metabolismo , Vaginose Bacteriana/microbiologia
14.
Int J Mol Sci ; 18(10)2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28981461

RESUMO

Abstract: Reductive stress (RS) is the counterpart oxidative stress (OS), and can occur in response to conditions that shift the redox balance of important biological redox couples, such as the NAD⁺/NADH, NADP⁺/NADPH, and GSH/GSSG, to a more reducing state. Overexpression of antioxidant enzymatic systems leads to excess reducing equivalents that can deplete reactive oxidative species, driving the cells to RS. A feedback regulation is established in which chronic RS induces OS, which in turn, stimulates again RS. Excess reducing equivalents may regulate cellular signaling pathways, modify transcriptional activity, induce alterations in the formation of disulfide bonds in proteins, reduce mitochondrial function, decrease cellular metabolism, and thus, contribute to the development of some diseases in which NF-κB, a redox-sensitive transcription factor, participates. Here, we described the diseases in which an inflammatory condition is associated to RS, and where delayed folding, disordered transport, failed oxidation, and aggregation are found. Some of these diseases are aggregation protein cardiomyopathy, hypertrophic cardiomyopathy, muscular dystrophy, pulmonary hypertension, rheumatoid arthritis, Alzheimer's disease, and metabolic syndrome, among others. Moreover, chronic consumption of antioxidant supplements, such as vitamins and/or flavonoids, may have pro-oxidant effects that may alter the redox cellular equilibrium and contribute to RS, even diminishing life expectancy.


Assuntos
Inflamação/metabolismo , Animais , Antioxidantes/metabolismo , Humanos , Inflamação/imunologia , Oxirredução , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo
15.
Malar J ; 15(1): 531, 2016 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-27809847

RESUMO

BACKGROUND: Plasmodium parasites may affect the oxidative status of their hosts, defined as the balance of pro-oxidant compounds and antioxidant defences in an organism. An increased energy requirement, the activation of immune functions or the parasite itself may lead to a higher production of pro-oxidants and/or an antioxidant depletion resulting in a higher oxidative stress and associated damage in infected individuals. Relatively little is known about the mechanisms underlying oxidative processes at play during host-Plasmodium interaction in the wild. METHODS: The effect of Plasmodium infection on host oxidative status was investigated in wild populations of breeding great tits, Parus major, naturally infected by Plasmodium spp. When chicks were 14 days old, the parents were blood-sampled to measure four complementary oxidative status markers: pro-oxidant production as mitochondrial superoxide production in red blood cells (RBC), antioxidant defences as plasma antioxidant capacity and oxidative damage as reactive oxygen metabolites in the plasma and RBC membrane resistance to oxidative attack. RESULTS: Plasmodium-infected individuals produced more pro-oxidants compared to uninfected ones and pro-oxidant production positively correlated to infection intensity. There was also a conditional effect of reproductive effort on oxidative damage depending on Plasmodium infection status. There was no direct effect of infection on oxidative damage and no effect on antioxidant defences. CONCLUSIONS: The results suggest that Plasmodium parasites may impose a cost in terms of increased oxidative stress possibly mediated via a higher energy requirement in infected hosts. This further suggests that Plasmodium parasites may modify host life history traits via an induction of oxidative stress. This study highlights that measuring several complementary oxidative status markers may enable to capture oxidative processes at play during host-Plasmodium interactions.


Assuntos
Cruzamento , Malária Aviária/patologia , Estresse Oxidativo , Passeriformes/parasitologia , Animais , Feminino , Masculino
16.
J Membr Biol ; 248(6): 1137-44, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26374653

RESUMO

Lipid peroxidation by ROS at the membrane level disturbs the inherit integrity of components activating subsequent alterations in the function. In this study, the protective effect of purified Sundakai (Solanum torvum) seed protein (SP) was tested against oxidative membrane damage in erythrocyte membrane. SP prevented oxidative RBC lysis induced by pro-oxidants; Fe:As (2:20 µmol), periodate (0.4 mM), and t-BOOH (1 mM) up to 86, 81, and 86 %, respectively. Further, SP prevented the Fe:As-induced K(+) leakage up to the tune of 95 %. The inhibition offered by SP on K(+) leakage was comparable to inhibition offered by quinine sulfate, a known K(+) channel blocker. SP dose dependently restored Na(+)K(+) ATPase and Ca(2+)Mg(2+) ATPase activities in erythrocyte membrane. The restoration of ATPase activity by SP was two times more than standard antioxidants BHA and α-tocopherol. Besides, SP at 1.6 µmol restored the membrane proteins over Fe:As induction when analyzed by SDS-PAGE, which was comparable to protection offered by BHA. In conclusion, SP is an effective antioxidant in preventing oxidative membrane damage and associated functions mediated by ROS. As SP is non-toxic, it can be used as an effective bioprotective antioxidant agent to cellular components.


Assuntos
Antioxidantes/farmacologia , Membrana Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteínas de Plantas/farmacologia , Substâncias Protetoras/farmacologia , Sementes/química , Solanum/química , ATPase de Ca(2+) e Mg(2+)/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Eritrócitos/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Oxirredução/efeitos dos fármacos , Potássio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo
17.
Polymers (Basel) ; 16(19)2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39408419

RESUMO

Enhancing the degradability of polyethylene plastics could provide a potential solution to the overwhelming crisis of plastic waste. Conventional studies have focused on the degradation of polyethylene thin films. This study investigated UV-induced photo-degradation according to ASTM D5208-14 in polyethylene sheets with thicknesses ranging from 0.4 to 1.2 mm. The impacts of sample thickness, metal pro-oxidants, polyethylene resin types and foaming were explored through the characterization of the carbonyl index, molecular weight, tensile properties and crystallinity. As pro-oxidants, single iron or manganese stearate demonstrated a concentration-dependent trend in accelerating the photo-degradation of polyethylene sheets. The thickness, foaming and resin type-such as low-density polyethylene (LDPE) and high-density polyethylene (HDPE)-significantly impacted the rate of photo-oxidation. Thick polyethylene sheets (1.2 mm) exhibited a heterogenous and depth-dependent degradation profile. As the photo-degradation progressed, the enhanced crystallinity, reduced UV transmittance and formation of crosslinks were able to prevent further oxidative cleavage of the polyethylene chain. This study investigated the time course and factors affecting the photo-degradation of polyethylene sheets, which could provide insights into the formulation design of photo-degradable polyethylene plastics.

18.
Redox Rep ; 29(1): 2333619, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38577911

RESUMO

KEY POLICY HIGHLIGHTSNanobubbles and nanoparticles may enhance the polyphenols' bioavailabilityNanobubbles may stimulate the activation of Nrf2 and detox enzymesArmoured oxygen nanobubbles may enhance radiotherapy or chemotherapy effects.


Assuntos
Antioxidantes , Nanopartículas , Antioxidantes/uso terapêutico , Disponibilidade Biológica , Polifenóis , Oxigênio
19.
Front Endocrinol (Lausanne) ; 15: 1386021, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39140031

RESUMO

Background: The correlation between oxidative stress and female infertility pathogenesis was established, and the oxidative balance score (OBS) can serve as a measure of overall oxidative stress burden within an individual. Prior reports have not addressed the relationship between OBS and female infertility. This study endeavors to investigate the association between infertility risk in female and OBS. Methods: The analysis focused on data from the National Health and Nutrition Examination Survey 2013-2018. OBS was determined from 16 dietary components and 4 lifestyle components. Multivariate logistic regression was employed to investigate the relationship between OBS and female infertility. Further stratified analysis was conducted to examine the associations across various subgroups. To elucidate the dose-response relationship between infertility risk in female and OBS, a restricted cubic spline function was employed. Results: The study included a total of 1410 participants. Through weighted multivariable logistic regression analysis, we observed a consistent inverse correlation between OBS and the risk of female infertility [OR (95% CI) = 0.97 (0.95, 0.99), p = 0.047]. When participants were segregated into quartiles based on OBS, those in the highest quartile had a 61% [OR (95% CI) = 0.39 (0.2, 0.79), p = 0.01] reduced risk of infertility compared to those in the lowest quartile of OBS. A trend test assessing OBS by quartile also revealed the relationship between OBS and female infertility. This correlation remained constant across both dietary and lifestyle OBS. Additionally, lifestyle OBS and female infertility exhibited a nonlinear association. A sensitivity analysis verified the consistency of our findings. Conclusion: The study found that a higher OBS is associated with a lower prevalence of female infertility. These results emphasized the potential role of oxidative homeostasis in the pathogenesis of infertility and highlighted the importance of follow-up studies and prevention strategies.


Assuntos
Infertilidade Feminina , Inquéritos Nutricionais , Estresse Oxidativo , Humanos , Feminino , Adulto , Infertilidade Feminina/epidemiologia , Infertilidade Feminina/metabolismo , Estilo de Vida , Adulto Jovem , Estudos Transversais , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Fatores de Risco , Dieta
20.
Antioxidants (Basel) ; 13(2)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38397808

RESUMO

Hyperprolific sows often experience increased oxidative stress during late gestation and lactation periods, which can adversely affect the farrowing process and overall lactation performance. This study examines the influence of providing a coconut coir mat (CCM; 1 × 1 m) as nesting material, supplementing high-dose vit-C (HVC; 20% vit-C, 10 g/kg feed) as an antioxidant, or both on maternal behavior, the farrowing process, oxidative status, cortisol levels, and preovulatory follicle developments in sows with large litters. In total, 35 sows (Landrace × Yorkshire; litter size 15.43 ± 0.27) were allocated to the following four treatment groups: control (n = 9, basal diet), vit-C (n = 8, basal diet + HVC), mat (n = 10, basal diet + CCM), and mat + vit-C (n = 8, basal diet + HVC + CCM). A post-hoc analysis showed that compared with sows that were not provided CCM, mat and mat + vit-C groups demonstrated increased durations of nest-building behavior during the period from 24 h to 12 h before parturition (p < 0.05 for both), reduced farrowing durations, and decreased intervals from birth to first udder contact (p < 0.01 for both). The mat group exhibited lower advanced oxidation protein product (AOPP) levels during late gestation and lactation periods than the control group (p < 0.05). Sows with HVC supplementation showed longer farrowing durations than those without HVC supplementation (p < 0.0001). The vit-C group had higher salivary cortisol levels on day 1 after farrowing than the other treatment groups (p < 0.05). Furthermore, the follicle diameters on day 3 after weaning in the vit-C group tended to be smaller than those in the control group (p = 0.077). HVC supplementation prolonged farrowing and increased the physiological stress on postpartum, and no advantageous effects on maternal behavior and developmental progression of preovulatory follicles were observed. Hence, alternative solutions beyond nutritional approaches are required to address increased oxidative stress in hyperprolific sows and secure their welfare and reproductive performance. The present results substantiated the positive impact of providing CCM as nesting material for sows with large litters on nest-building behavior and the farrowing process, which could mitigate the deleterious consequences induced by peripartum physiological and oxidative stress.

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