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ABSTRACT Purpose: This study aimed to determine the effect of serum G receptor-mediated protein-1 levels on the development of retinopathy in patients with diabetes in comparison with healthy individuals. Methods: The study enrolled patients with diabetic retinopathy (Group 1), patients without diabetic retinopathy (Group 2), and healthy individuals (Group 3). Levels of serum progesterone, serum G receptor-mediated protein-1, estradiol, oxidant/antioxidants, and thyroid-releasing hormones were analyzed and compared among the groups. Post-hoc analysis was performed to compare the subgroups in which significant differences were found. Results: Groups 1, 2, and 3 each included 40 patients. A significant difference was found among all groups in terms of serum G receptor-mediated protein-1, oxidant/antioxidant, and estradiol levels (p<0.01), but no significant difference was found in terms of thyroid-releasing hormone or progesterone (p=0.496, p=0.220, respectively). In the post-hoc analysis of the groups with significant differences, another significant difference was found among all groups for serum G receptor-mediated protein-1 and oxidant/antioxidant levels (p<0.05). Serum G receptor-mediated protein-1 and oxidant levels were positively correlated, whereas serum G receptor-mediated protein-1 and antioxidant levels were negatively correlated (r=0.622/p<0.01, r=0.453/p<0.01, r=0.460/p<0.01, respectively). The multiple regression analysis showed that increased levels of serum G receptor-mediated protein-1 may help prevent diabetic retinopathy. Conclusions: Serum G receptor-mediated protein-1 levels, which were the highest in the diabetic retinopathy Group, increased as the oxidant/antioxidant balance changed in favor of oxidative stress. This appears to be a defense mechanism for preventing neuronal damage.

RESUMO Objetivo: Esta pesquisa buscou determinar o im­pacto dos níveis de proteína G sérica no desenvolvimento da retinopatia em pacientes diabéticos, comparando-os a indivíduos saudáveis. Métodos: Foram incluídos, no estudo, 40 pacientes com retinopatia diabética (Grupo 1), 40 pacientes sem retinopatia diabética (Grupo 2) e 40 indivíduos saudáveis (Grupo 3). Os níveis hormonais de progesterona sérica, de proteína G sérica, estradiol, oxidante/antioxidante e hormônio liberado pela tireoide foram analisados e comparados. A análise post hoc foi realizada para comparar os subgrupos nos quais diferenças estatisticamente significativas foram encontradas. Resultados: Uma diferença significativa foi encontrada entre todos os grupos em termos de proteína G sérica, oxidante/antioxidante e níveis de estradiol (p<0.01), mas nenhuma diferença significativa foi encontrada em termos de hormônio liberado pela tireoide ou progesterona (p=0,496, p=0,220, respectivamente). Na análise post hoc dos grupos com diferenças estatisticamente significativas, outra diferença significativa foi encontrada entre todos os grupos para proteína G sérica e níveis oxidantes/antioxidantes (p<0,05). Os níveis de proteína G sérica e os níveis de oxidante foram positivamente correlacionados, enquanto os níveis de proteína G sérica e os níveis de antioxidantes foram negativamente correlacio­nados (r=0,622/p<0,01, r=0,453/p<0,01, r=0,460/p<0,01, respectivamente). A análise de regressão múltipla mos­trou que o aumento da proteína G sérica pode ajudar a prevenir a retinopatia diabética. Conclusões: Os níveis de proteína G sérica que eram mais altos no grupo de retinopatia diabética, aumentaram à medida que o equilíbrio oxidante/antioxidante mudou em favor do estresse oxidativo. Este parece ser um mecanismo de defesa para prevenir danos neuronais.

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The in vitro production and cryopreservation of mammalian embryos generates reactive oxygen species (ROS) due to conditions of the system that can overcome their antioxidant protection. Resveratrol is an antioxidant used in in vitro systems to improve blastocyst rates, but its effect on antioxidant enzymes such as glutathione (GSH) in embryos produced by in vitro fertilization (IVF) after vitrification has not been reported. The objective of this study was to evaluate the effects of resveratrol on the in vitro maturation medium (IVM) of sheep oocytes (Ovis aries) on the levels of ROS and GSH in embryos produced by IVF subjected to vitrification. Resveratrol was added at 0 µM, 0.25 µM, 0.5 µM, and 1 µM during oocyte in vitro maturation (IVM). Matured oocytes were fertilized with thawed ram sperm. Embryos were cultured in sequential media until blastocysts, were then vitrified for 24 h, and, after heating, they were stained with DCFH-DA (2',7'-dichlorodihydrofluorescein diacetate) to determine the presence of ROS and with Cell Tracker Blue® for the presence of GSH. The quantitative values of ROS and GSH were obtained through the Image J image processor. The results showed that resveratrol increased GSH and decreased ROS production (p < 0.05) in a dose-dependent manner. It is concluded that its use in sheep oocytes during IVM has a beneficial effect on embryos produced by IVF subjected to vitrification by decreasing reactive oxygen species levels and facilitating the generation of embryo antioxidant enzymes like glutathione.

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Many natural products have been acquired from plants for their helpful properties. Medicinal plants are used for treating a variety of pathologies or symptoms. The axes of many pathological processes are inflammation, oxidative stress, and senescence. This work is focused on identifying Mexican medicinal plants with potential anti-oxidant, anti-inflammatory, anti-aging, and anti-senescence effects through network analysis and chemoinformatic screening of their phytochemicals. We used computational methods to analyze drug-like phytochemicals in Mexican medicinal plants, multi-target compounds, and signaling pathways related to anti-oxidant, anti-inflammatory, anti-aging, and anti-senescence mechanisms. A total of 1373 phytochemicals are found in 1025 Mexican medicinal plants, and 148 compounds showed no harmful functionalities. These compounds displayed comparable structures with reference molecules. Based on their capacity to interact with pharmacological targets, three clusters of Mexican medicinal plants have been established. Curatella americana, Ximenia americana, Malvastrum coromandelianum, and Manilkara zapota all have anti-oxidant, anti-inflammatory, anti-aging, and anti-senescence effects. Plumeria rubra, Lonchocarpus yucatanensis, and Salvia polystachya contained phytochemicals with anti-oxidant, anti-inflammatory, anti-aging, and anti-senescence reported activity. Lonchocarpus guatemalensis, Vallesia glabra, Erythrina oaxacana, and Erythrina sousae have drug-like phytochemicals with potential anti-oxidant, anti-inflammatory, anti-aging, and anti-senescence effects. Between the drug-like phytochemicals, lonchocarpin, vallesine, and erysotrine exhibit potential anti-oxidant, anti-inflammatory, anti-aging, and anti-senescence effects. For the first time, we conducted an initial virtual screening of selected Mexican medicinal plants, which was subsequently confirmed in vivo, evaluating the anti-inflammatory activity of Lonchocarpus guatemalensis Benth in mice.

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Mitochondrial dysfunction is an interesting therapeutic target to help reduce cancer deaths, and the use of bioactive compounds has emerged as a novel and safe approach to solve this problem. Here, we discuss the information available related to phlorotannins, a type of polyphenol present in brown seaweeds that reportedly functions as antioxidants/pro-oxidants and anti-inflammatory and anti-tumorigenic agents. Specifically, available evidence indicates that dieckol and phloroglucinol promote mitochondrial membrane depolarization and mitochondria-dependent apoptosis. Phlorotannins also reduce pro-tumorigenic, -inflammatory, and -angiogenic signaling mechanisms involving RAS/MAPK/ERK, PI3K/Akt/mTOR, NF-κB, and VEGF. In doing so, they inhibit pathways that favor cancer development and progression. Unfortunately, these compounds are rather labile and, therefore, this review also summarizes approaches permitting the encapsulation of bioactive compounds, like phlorotannins, and their subsequent oral administration as novel and non-invasive therapeutic alternatives for cancer treatment.

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A cúrcuma longa é amplamente conhecida por seu uso culinário e na estética. A curcumina, um antioxidante da cúrcuma, possui propriedades que impactam diretamente na regeneração da pele e na cicatrização de feridas. Neste sentido, este estudo tem como objetivo geral apresentar a cúrcuma longa e seus benefícios quanto ao consumo oral nos tratamentos dermatológicos. Para desenvolvimento deste estudo, optou-se pelo método de revisão bibliográfica. A ingestão de cúrcuma longa, precisa ser amplamente estudada e divulgada, uma vez que seus benefícios vêm de sua composição, principalmente da curcumina. Não se deve ignorar que sua ingestão provoca resultados e efeitos extremamente melhores do que seu uso tópico, e quanto mais próximo do natural, longe da industrialização, mais concentrado será o produto. Por fim, a presente pesquisa não esgota o tema em questão, por isso, sugere-se a realização de um novo estudo, onde seja avaliado as diferenças de resultados e bene

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INTRODUCTION: The effect of gestational age and fetal growth on the oxidant/antioxidant status of breast milk is poorly understood. OBJECTIVE: To evaluate the oxidative stress biomarkers in colostrum and mature milk according to gestational age and fetal growth. METHOD: A longitudinal study with mothers of premature and term infants, born in a tertiary referral hospital between 2014-2018. Inclusion criteria: postpartum women with a singleton pregnancy, who intended to exclusively breastfeed. Exclusion criteria: maternal diabetes, use of medication, drug addiction, congenital infection or malformation, mastitis, and failure to collect colostrum. Four groups were formed according to gestational age and birth weight (appropriate and small): Preterm small (n = 37), Preterm appropriate (n = 99), Full-term small (n = 65), and Full-term appropriate (control, n = 69). The colostrum samples were collected between 24-72 h and the mature milk was sampled in the 4th week of lactation for malondialdehyde (biomarker for lipid peroxidation) and Glutathione peroxidase, Catalase, and Superoxide dismutase measurements. The data were compared among groups using the Chi-square test or Fisher's exact test, one-way analysis of variance followed by Wald's Distribution test and repeated measures analysis of variance. RESULTS: We found a lower malondialdehyde level in colostrum in preterm groups and term small for gestational age, and the antioxidant enzymes Superoxide dismutase and Catalase activities were higher for preterm compared to term groups. The malondialdehyde levels differed in mature milk samples (Full-term small > Full-term appropriate > Preterm small > Preterm appropriate). The malondialdehyde levels increased during lactation in all groups except Preterm appropriate, and the levels of Catalase decreased in preterm groups. CONCLUSION: The oxidative status in breast milk is influenced by gestational age and fetal growth, which increased antioxidant defense for preterm infants and decreased oxidative stimuli for small for gestational age infants. These findings contribute to encouraging breastfeeding for newborns.

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End-stage renal disease (ESRD) progression is closely related to oxidative stress (OS). The study objective was to determine the oxidant and antioxidant status in peritoneal dialysis (PD) patients with type 2 diabetes mellitus (DM). An analytical cross-sectional study from the PD program was carried out with 62 patients, 22 with and 40 without DM. Lipoperoxides (LPO) levels in patients with DM, 3.74 ± 1.09 mM/L, and without DM, 3.87 ± 0.84 mM/L were found to increase compared to healthy controls (HC) 3.05 ± 0.58 mM/L (p = 0.006). The levels of the oxidative DNA damage marker (8-OH-dG) were found to be significantly increased in patients with DM, 1.71 ng/mL (0.19-71.92) and without DM, 1.05 ng/mL (0.16-68.80) front to 0.15 ng/mL (0.15-0.1624) of HC (p = 0.001). The antioxidant enzyme superoxide dismutase (SOD) activity was found to be significantly increased in patients with DM, 0.37 ± 0.15 U/mL, and without DM, 0.37 ± 0.17 compared to HC, 0.23 ± 0.05 U/mL (p = 0.038). The activity of the enzyme glutathione peroxidase (GPx) showed a significant increase (p < 0.001) in patients with DM, 3.56 ± 2.18 nmol/min/mL, and without DM, 3.28 ± 1.46 nmol/min/mL, contrary to the activity obtained in HC, 1.55 ± 0.34 nmol/min/mL. In conclusion, we found an imbalance of oxidative status in patients undergoing PD with and without DM through the significant increase in LPO oxidants and the marker of oxidative damage in DNA. The activity of the antioxidant enzymes SOD and GPx were significantly increased in patients with and without DM undergoing PD, possibly in an attempt to compensate for the deregulation of oxidants. Antioxidant enzymes could be promising therapeutic strategies as a complement to the management of chronic kidney diseases.

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Glutamine synthetase (GS), which catalyzes the ATP-dependent synthesis of L-glutamine from L-glutamate and ammonia, is a ubiquitous and conserved enzyme that plays a pivotal role in nitrogen metabolism across all life domains. In vertebrates, GS is highly expressed in astrocytes, where its activity sustains the glutamate-glutamine cycle at glutamatergic synapses and is thus essential for maintaining brain homeostasis. In fact, decreased GS levels or activity have been associated with neurodegenerative diseases, with these alterations attributed to oxidative post-translational modifications of the protein, in particular tyrosine nitration. In this study, we expressed and purified human GS (HsGS) and performed an in-depth analysis of its oxidative inactivation by peroxynitrite (ONOO-) in vitro. We found that ONOO- exposure led to a dose-dependent loss of HsGS activity, the oxidation of cysteine, methionine, and tyrosine residues and also the nitration of tryptophan and tyrosine residues. Peptide mapping by LC-MS/MS through combined H216O/H218O trypsin digestion identified up to 10 tyrosine nitration sites and five types of dityrosine cross-links; these modifications were further scrutinized by structural analysis. Tyrosine residues 171, 185, 269, 283, and 336 were the main nitration targets; however, tyrosine-to-phenylalanine HsGS mutants revealed that their sole nitration was not responsible for enzyme inactivation. In addition, we observed that ONOO- induced HsGS aggregation and activity loss. Thiol oxidation was a key modification to elicit aggregation, as it was also induced by hydrogen peroxide treatment. Taken together, our results indicate that multiple oxidative events at various sites are responsible for the inactivation and aggregation of human GS.

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Esse estudo avaliou o impacto do tratamento com cloridrato de metilfenidato (MFD) em crianças com Transtorno de Déficit de Atenção e Hiperatividade. O estudo incluiu metodologia variada, contendo estudo de revisão sobre efeito de metilfenidato sobre BDNF e estudo de coorte experimental. O estudo de revisão seguiu as diretrizes do PRISMA e foi registrado no PROSPERO. No estudo experimental, coorte aberta de centro único foi desenhada, com amostra de conveniência recrutada entre os anos de 2020 e 2022, no ambulatório de ensino da faculdade de Medicina da Universidade Federal de Viçosa (MG). Amostra de 62 crianças, 6 a 14 anos incompletos, sem tratamento prévio, diagnosticadas por psiquiatra infantil segundo os critérios do Manual Diagnóstico e Estatístico dos Transtornos Mentais (DSM5). Média de 8 consultas de acompanhamento clínico realizadas, com coletas de amostras biológicas em 3 delas: antes do início do MFD, com 12 e 24 semanas após uso da medicação. Amostra caracterizada quanto a dados sociodemográficos, sintomas de TDAH, avaliações clínica e psiquiátrica e testagem de inteligência pela psicologia. Amostras biológicas para dosagens séricas de marcadores oxidativos (níveis de capacidade antioxidante total -FRAP -, atividade de superóxido dismutase ­ SOD-, catalase ­ CAT -, glutathione -S-transferase -GST-, níveis de peroxidação lipídica e de proteínas carboniladas) foram coletadas de cada criança nos três momentos da avaliação. Metilfenidato de liberação imediata foi administrado na dosagem de média de 0,65mg/kg/dia. Usou-se o teste de Shapiro-Wilk e Kolmogorov-Smirnov para análise de normalidade. Frequências absolutas e relativas foram determinadas para as variáveis numéricas que foram descritas por suas médias e desvios padrões. Para comparações múltiplas dos parâmetros oxidativos foi realizado pós teste paramétrico de Tukey e para as demais variáveis análise de variância ANOVA (f). Análises dos parâmetros oxidativos foram realizadas no programa GraphPad Prism 7.0 (GraphPad Software, Inc. San Diego, CA, USA) e dos dados sociodemográficos e clínicos no software SPSS (versão 23.0 para Windows). Significância estatística foi considerada com p <0.05. Os resultados mostram: Sexo masculino predominante (71%), idade média 8,58 ± 1,91, predominância de apenas um cuidador - mãe e/ou pai biológico como chefe de família e maior frequência de tipo combinado de TDAH. Pressão arterial sistólica, frequência cardíaca e temperatura corporal alterações significativas, porém sem significância clínica. Índice massa corporal com diferença estatística, 37%, 19,3% e 21% das crianças apresentaram IMC acima do esperado para idade na avaliação 1, 2 e 3 respectivamente. Adesão ao tratamento medicamentoso permaneceu acima de 93,5% na 24ª semana. Durante o tratamento: FRAP não se alterou; atividade de SOD reduziu na 12ª semana em comparação à linha de base; atividade de CAT aumento significativo à 24ª em comparação 12ª semana; aumento significativo dos níveis de peroxidação lipídica à 24ª semana em comparação à 12ª semana. Aumento significativo das proteínas carboniladas na linha de base em comparação aos níveis da 12ª e 24ª semanas. O metilfenidato parece influenciar os parâmetros redox de crianças com TDAH, aumentando o estresse oxidativo. Porém, mecanismos cerebrais tamponam e desconhecemos o resultado dessas interações na estrutura cerebral. Níveis de BDNF não foram influenciados significativamente por metilfenidato em crianças com TDAH, quando comparados a controles em nossa metanálise.

This study evaluated the impact of methylphenidate hydrochloride (MFD) treatment (MFD) in children with Attention Deficit Hyperactivity Disorder. The study included varied methodology, including a review study about methylphenidate effects on BDNF and an experimental cohort study. The review study followed the PRISMA guidelines and was registered in PROSPERO. In the experimental study, a single-center open cohort was designed, with a convenience sample recruited between the years 2020 and 2022, at the teaching outpatient clinic of the Faculty of Medicine at Viçosa Federal University (UFV-MG). Sample with 62 children, 6 to 14 years old, without previous treatment, diagnosed by a child psychiatrist according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders (DSM5). Eight clinical follow-up visits were carried out, and biological samples were collected in 3 visits: before MFD beginning and after 12- and 24-weeks medication. Sociodemographic data, ADHD symptoms, clinical and psychiatric assessments were performed, as well as intelligence testing by psychology. Biological samples for oxidative markers serum dosages (total antioxidant capacity levels -FRAP -, superoxide dismutase activity - SOD-, catalase - CAT -, glutathione S transferase -GST-, lipid peroxidation and carbonyl proteins levels) were collected of each child in the 3 evaluation moments. Immediate-release methylphenidate was administered at approximately 0.65mg/kg/day. The Shapiro-Wilk and Kolmogorov-Smirnov test was used for normality analysis. Absolute and relative frequencies were used for numeric variables that were described by their means and standard deviations. Tukey's parametric test and variance analysis ANOVA (f) were performed for multiple comparisons in redox parameters and other variables respectively. Redox parameters analysis was performed using GraphPad Prism 7.0 program (GraphPad Software, Inc. San Diego, CA, USA) and other variables using SPSS software (version 23.0 for Windows). Statistical significance was considered at p<0.05. Male was predominant (71%), with a mean age of 8.58 ± 1.91, mother and/or biological father were the householder in most homes. Systolic blood pressure, heart rate and body temperature had significant changes, but without clinical significance. Body mass index showed a statistical difference, with 37%, 19.3% and 21% of the children having a BMI above the expected for their age in assessment 1, 2 and 3 respectively. Combined-ADHD occurred in 58.1% of the children, inattentive in 32.3% and hyperactive/impulsive in 9.7%. Drug treatment adherence was 98.4% (12th week) and 93.5% (24th week). There were no changes in FRAP levels; SOD activity had significant decreased at week 12 compared to baseline activity; CAT activity showed a significant increase at the 24th week compared to 12th week; Significant increase in lipid peroxidation levels at 24th week compared to 12th week. Significant increase in protein carbonyls levels at baseline (before methylphenidate use) compared to levels at 12 and 24 weeks. Methylphenidate can influence the oxidative and antioxidative parameters of ADHD children, increasing oxidative stress. However, buffer brain mechanisms may act and the result of these interactions in brain structure is not completely known. BDNF levels were not significantly affected by methylphenidate treatment in ADHD children and do not differ from controls in our meta-analysis.

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SUMMARY OBJECTIVE: This study aimed to evaluate the association between left ventricular ejection fraction recovery and the total oxidant status, total antioxidant capacity, and high-sensitivity C-reactive protein levels. METHODS: A total of 264 ST-elevation myocardial infarction patients were classified into two groups according to baseline and 6-month follow-up left ventricular systolic function: reduced and recovery systolic function. Predictors of the recovery of left ventricular ejection fraction were determined by multivariate regression analyses. RESULTS: Multivariable analysis indicated that oxidative status index, baseline left ventricular ejection fraction and peak creatine-kinase myocardial bundle level, and high-sensitivity C-reactive protein were independently associated with the decreased of left ventricular ejection fraction at 6-month follow-up. CONCLUSION: Oxidative stress and inflammation parameters were detrimental to the recovery of left ventricular ejection fraction in patients with ST-elevation myocardial infarction.

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Plasma cholesteryl ester transfer protein (CETP) activity diminishes HDL-cholesterol levels and thus may increase atherosclerosis risk. Experimental evidence suggests CETP may also exhibit anti-inflammatory properties, but local tissue-specific functions of CETP have not yet been clarified. Since oxidative stress and inflammation are major features of atherogenesis, we investigated whether CETP modulates macrophage oxidant production, inflammatory and metabolic profiles. Comparing macrophages from CETP-expressing transgenic mice and non-expressing littermates, we observed that CETP expression reduced mitochondrial superoxide anion production and H2O2 release, increased maximal mitochondrial respiration rates, and induced elongation of the mitochondrial network and expression of fusion-related genes (mitofusin-2 and OPA1). The expression of pro-inflammatory genes and phagocytic activity were diminished in CETP-expressing macrophages. In addition, CETP-expressing macrophages had less unesterified cholesterol under basal conditions and after exposure to oxidized LDL, as well as increased HDL-mediated cholesterol efflux. CETP knockdown in human THP1 cells increased unesterified cholesterol and abolished the effects on mitofusin-2 and TNFα. In summary, the expression of CETP in macrophages modulates mitochondrial structure and function to promote an intracellular antioxidant state and oxidative metabolism, attenuation of pro-inflammatory gene expression, reduced cholesterol accumulation, and phagocytosis. These localized functions of CETP may be relevant for the prevention of atherosclerosis and other inflammatory diseases.

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Biochar (BP) obtained from palm fiber wastes was combined with H2O2, peroxymonosulfate (PMS), or persulfate (PDS) to treat valsartan, acetaminophen, and cephalexin in water. BP activated PMS and PDS but no H2O2. Computational calculations indicated that interactions of PMS and PDS with BP are more favored than those with HP. The highest synergistic effect was obtained for the removal of valsartan by BP + PMS. This carbocatalytic process was optimized, evaluating the effects of pH, BP dose, and peroxymonosulfate concentration, and minimizing the oxidant quantity to decrease costs and environmental impacts of the process. SO4•-, HO•, 1O2, and O2•- were the agents involved in the degradation of the pharmaceuticals. The reusability of BP was tested, showing that the carbocatalytic process removed ∼80% of target pollutants after 120 min of treatment even at the fourth reuse cycle. Also, the process decreased the phytotoxicity of the treated sample. Simulated hospital wastewater was treated and its components induced competing effects, but the system achieved the target pharmaceuticals removal in this matrix. Additionally, the analysis of environmental impact using a life cycle assessment unraveled that the carbocatalytic process had a carbon footprint of 2.87 Kg CO2-Eq, with the biochar preparation (which involves the use of ZnCl2 and electric energy consumption) as the main hotspot in the process.

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Objectives: To evaluate the effects of Amburana cearensis leaf extract against cisplatin-induced ovarian toxicity in mice and involvement of p-PTEN and p-Akt proteins. Materials and Methods: A. cearensis ethanolic leaf extract was analyzed by high-performance liquid chromatography (HPLC). Mice were pretreated once daily for 3 days as follows: (1) the control group was pretreated with oral administration (o.p.) of saline solution, followed by intraperitoneal (IP) injection of saline solution. The other groups were pretreated (o.p.) with (2) saline solution (cisplatin group), (3) N-acetylcysteine (positive control), with (4) 50, or (5) 200 mg/kg body weight of A. cearensis extract, followed by injection of 5 mg/kg body weight (IP) of cisplatin. The ovaries were harvested and destined for histological (follicular morphology), immunohistochemistry (apoptosis and cell proliferation), and fluorescence (reactive oxygen species [ROS], glutathione concentrations [GSH], and active mitochondria) analyses. Furthermore, immunoexpression of p-PTEN and p-Akt was evaluated to elucidate a potential mechanism by which A. cearensis extract could prevent cisplatin-induced ovarian damage. Results: After HPLC analysis, protocatechuic acid was detected in the extract. The pretreatment with N-acetylcysteine or A. cearensis extract maintained the percentage of normal follicles and cell proliferation, reduced apoptosis and ROS concentrations, and increased GSH concentrations and mitochondrial activity compared with cisplatin treatment. Furthermore, pretreatment with A. cearensis extract regulated p-PTEN and p-Akt immunoexpression after cisplatin exposure. Conclusion: Pretreatment with A. cearensis extract prevented cisplatin-induced ovarian damage through its anti-oxidant actions and by modulating the expression of phosphorylated PTEN and Akt proteins.

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In an attempt to reduce the accumulation of polymeric waste in the environment, such as plastic bags, the use of pro-oxidants has been adopted in polyolefins, including polyethylene (PE), which is one of the most used polymers in film production. The incorporation of this additive to PE film aims to accelerate its oxidation in the process of abiotic degradation, generating oxygenated groups that can facilitate the biotic degradation. Commercial pro-oxidants are commonly organic salts of transition metals. However, their use can lead to a secondary problem, the inappropriate accumulation of transition metals at the site where the polymeric waste was deposited and, for this reason, it has been sought pro-oxidants metals free and that can also be biodegraded. In this context, this work aimed to evaluate the photodegradation of PE blown films obtained by extrusion using a commercial pro-oxidant, d2w™, an alternative organic pro-oxidant, benzoin, and also a standard film, without pro-oxidant. After undergoing 96 and 144 h of UV light exposure, the blown films were evaluated by dilute solution viscometry, FTIR and SEM analysis. The results showed that the pro-oxidants lead to the formation of more macromolecular fragments containing carbonyl groups than in the standard PE film. The film extruded with benzoin showed greater fragmentation, which may be associated with a greater reduction in the average viscosimetric molar mass, therefore, this additive being a promising organic substance in the induction of photooxidation, as demonstrated by the other results obtained by FTIR and SEM.

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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.

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Diabetes in humans a chronic metabolic disorder characterised by hyperglycaemia, it is associated with an increased risk of cardiovascular disease, disruptions to metabolism and vascular functions. It is also linked to oxidative stress and its complications. Its role in vascular dysfunctions is generally reported without detailed impact on the molecular mechanisms. Potassium ion channel (K+ channels) are key regulators of vascular tone, and as membrane proteins, are modifiable by oxidant stress associated with diabetes. This review manuscript examined the impact of oxidant stress on vascular K+ channel functions in diabetes, its implication in vascular complications and metabolic and cardiovascular diseases.

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Headaches are frequently described in progressive multiple sclerosis (PMS) patients, but their mechanism remains unknown. Transient receptor potential ankyrin 1 (TRPA1) was involved in neuropathic nociception in a model of PMS induced by experimental autoimmune encephalomyelitis (PMS-EAE), and TRPA1 activation causes periorbital and facial nociception. Thus, our purpose was to observe the development of periorbital mechanical allodynia (PMA) in a PMS-EAE model and evaluate the role of TRPA1 in periorbital nociception. Female PMS-EAE mice elicited PMA from day 7 to 14 days after induction. The antimigraine agents olcegepant and sumatriptan were able to reduce PMA. The PMA was diminished by the TRPA1 antagonists HC-030031, A-967079, metamizole and propyphenazone and was absent in TRPA1-deficient mice. Enhanced levels of TRPA1 endogenous agonists and NADPH oxidase activity were detected in the trigeminal ganglion of PMS-EAE mice. The administration of the anti-oxidants apocynin (an NADPH oxidase inhibitor) or alpha-lipoic acid (a sequestrant of reactive oxygen species), resulted in PMA reduction. These results suggest that generation of TRPA1 endogenous agonists in the PMS-EAE mouse model may sensitise TRPA1 in trigeminal nociceptors to elicit PMA. Thus, this ion channel could be a potential therapeutic target for the treatment of headache in PMS patients.

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Pseudomonas aeruginosa is an opportunistic bacterium in patients with cystic fibrosis and hospital acquired infections. It presents a plethora of virulence factors and antioxidant enzymes that help to subvert the immune system. In this study, we identified the 2-Cys peroxiredoxin, alkyl-hydroperoxide reductase C1 (AhpC1), as a relevant scavenger of oxidants generated during inflammatory oxidative burst and a mechanism of P. aeruginosa (PA14) escaping from killing. Deletion of AhpC1 led to a higher sensitivity to hypochlorous acid (HOCl, IC50 3.2 ± 0.3 versus 19.1 ± 0.2 µM), hydrogen peroxide (IC50 91.2 ± 0.3 versus 496.5 ± 6.4 µM) and the organic peroxide urate hydroperoxide. ΔahpC1 strain was more sensitive to the killing by isolated neutrophils and less virulent in a mice model of infection. All mice intranasally instilled with ΔahpC1 survived as long as they were monitored (15 days), whereas 100% wild-type and ΔahpC1 complemented with ahpC1 gene (ΔahpC1 attB:ahpC1) died within 3 days. A significantly lower number of colonies was detected in the lung and spleen of ΔahpC1-infected mice. Total leucocytes, neutrophils, myeloperoxidase activity, pro-inflammatory cytokines, nitrite production and lipid peroxidation were much lower in lungs or bronchoalveolar liquid of mice infected with ΔahpC1. Purified AhpC neutralized the inflammatory organic peroxide, urate hydroperoxide, at a rate constant of 2.3 ± 0.1 × 106 M-1s-1, and only the ΔahpC1 strain was sensitive to this oxidant. Incubation of neutrophils with uric acid, the urate hydroperoxide precursor, impaired neutrophil killing of wild-type but improved the killing of ΔahpC1. Hyperuricemic mice presented higher levels of serum cytokines and succumbed much faster to PA14 infection when compared to normouricemic mice. In summary, ΔahpC1 PA14 presented a lower virulence, which was attributed to a poorer ability to neutralize the oxidants generated by inflammatory oxidative burst, leading to a more efficient killing by the host. The enzyme is particularly relevant in detoxifying the newly reported inflammatory organic peroxide, urate hydroperoxide.

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A lot of diseases are characterized by an increased inflammatory response with an exacerbated production of free radicals. The anti-inflammatory effect of different compounds with antioxidant capacity, as polyphenols present in grape is well known. Therefore, the objective is to evaluate the anti-oxidant and anti-inflammatory activity of waste product of wine production.Six different non-toxic-marc-polar extracts from Malbec and Syrah grape varieties were obtained, their total phenol and flavonoid content were evaluated, and their antioxidant and anti-inflammatory activity were determined.High content of total phenols and flavonoids were found mainly in extracts obtained from Syrah (80.51 ± 16.63 g equivalent to gallic acid/100 g and 25.47 ± 3.33 g equivalent to quercetin/100 g). In addition, they had a high antioxidant effect (above 88.5% of ABTS inhibition by Syrah extracts). Finally, all extracts decreased the nitric oxide (NO) production, but this was more accented when extract from Syrah obtained by infusion was used, which decreased NO levels to baseline (4.46 µM).Taking together, our results show the potential pharmaceutical use of waste product of wine making to prevent or to treat diseases which inflammatory response is exacerbated.

Assuntos

RESUMO

It has previously been established during the elimination of organic matter that the addition of sodium dodecyl sulfate in solution is an important condition in the electrochemical oxidation approach that allows to increase the production of persulfate, enhancing the efficacy of the treatment. This outcome was observed when using the anodic oxidation with boron doped diamond (BDD), the extra production of persulfate was achieved after the SDS-sulfate released in solution and it reacts with hydroxyl radicals electrogenerated at BDD surface. However, this effect was not already tested by using active anodes. For this reason, the effect of sodium dodecyl sulfate (SDS) during the electrochemical treatment of caffeine was investigated by comparing non-active and active anodes performances. A significant decrease on the oxidation efficiency of caffeine was observed by using Ti/IrO2-Ta2O5 anode at high current density when SDS was added to the solution. Conversely, at BDD anode, the presence of SDS enhanced the degradation efficiency, depending on the applied current density. This behavior is mainly due to the degradation of SDS molecules, which allows to increase the amount of sulfate in solution, promoting the production of persulfate via the mechanism involving hydroxyl radicals when BDD is used. Meanwhile, no oxidation improvements were observed when Ti/IrO2-Ta2O5 anode was employed, limiting the caffeine oxidation. Results clearly showed that the surfactant concentration had little influence on the degradation efficiency, but this result is satisfactory for the BDD system, since it demonstrates that effluents with complex matrices containing surfactants could be effectively degraded using the electrooxidation technique. Degradation mechanisms were explained by electrochemical measurements (polarization curves) as well as the kinetic analysis. Costs and energy consumption were also evaluated.

Assuntos