RESUMO

A instabilidade de microssatélites é um fenômeno genético caracterizado pela alteração na repetição de sequências de nucleotídeos conhecidas como microssatélites. Esta instabilidade pode ocorrer devido a defeitos nos genes reparadores de DNA, como os genes MLH1, MSH2, MSH6 e PMS2. A inflamação crônica tem sido associada ao desenvolvimento do câncer colorretal. Os genes da instabilidade de microssatélites estão envolvidos na regulação da resposta inflamatória, podendo influenciar a progressão tumoral. Estudos demonstraram que a presença de instabilidade de microssatélites em tumores colorretais está relacionada a uma maior infiltração de células imunes, como linfócitos T, macrófagos e neutrófilos, que podem modular a resposta inflamatória no microambiente tumoral. O estresse oxidativo é caracterizado pelo desequilíbrio entre a produção de espécies reativas de oxigênio e a capacidade antioxidante do organismo e desempenha um papel importante na carcinogênese. Os genes da instabilidade de microssatélites podem influenciar a resposta ao estresse oxidativo, afetando a capacidade das células tumorais de lidar com o dano oxidativo e promovendo a sobrevivência celular. O objetivo deste trabalho consiste na compreensão dos genes envolvidos na instabilidade de microssatélites no câncer colorretal e como eles contribuem para o desenvolvimento da doença, relacionando com processos inflamatórios e estresse oxidativo nas células tumorais. Justifica-se pela necessidade de compreensão das interconexões entre a instabilidade de microssatélites, inflamação e o estresse oxidativo em pacientes com câncer colorretal.

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Microsatellite instability is a genetic phenomenon characterized by changes in the repetition of nucleotide sequences known as microsatellites. This instability may occur due to defects in DNA repair genes, such as the MLH1, MSH2, MSH6 and PMS2 genes. Chronic inflammation has been linked to the development of colorectal cancer. Microsatellite instability genes are involved in regulating the inflammatory response and may influence tumor progression. Studies have shown that the presence of microsatellite instability in colorectal tumors is related to a greater infiltration of immune cells, such as T lymphocytes, macrophages and neutrophils, which can modulate the inflammatory response in the tumor microenvironment. Oxidative stress is characterized by the imbalance between the production of reactive oxygen species and the body's antioxidant capacity and plays an important role in carcinogenesis. Microsatellite instability genes can influence the response to oxidative stress, affecting the ability of tumor cells to deal with oxidative damage and promoting cell survival. The objective of this work is to understand the genes involved in microsatellite instability in colorectal cancer and how they contribute to the development of the disease, relating it to inflammatory processes and oxidative stress in tumor cells. It is justified by the need to understand the interconnections between microsatellite instability, inflammation and oxidative stress in patients with colorectal cancer.

Assuntos

Humanos

RESUMO

SUMMARY: Resveratrol (RES) and quercetine (QRC), is a promising agent relevant for both cancer chemoprevention and treatment via several signaling pathways, involved in their anticancer activity related to its chemotherapeutic potential, associated with the induction of ROS generation in cancer cells, leading to apoptosis. In our study, we have summarized the mechanisms of action of RES and QRC, and their pharmacological implications and potential therapeutic applications in cancer therapy. After treatment of Hep 2 cells with QRC or RES, the death pathways such as the cytochrome c release, ERK1/2 and IRS-1 pathways were upregulated, while cell survival pathway, including PI3K/AKT were downregulated. The RES and QRC caused oncosis, cells hypertrophy, hypercondensatin of chromatin, rupture of the plasma membrane and nuclear membrane, and formation of apoptotic bodies. Morphometric measurements of some cellular and nuclear parameters showed that RES and QRC induced an increase in cells and nuclear size, the nucleocytoplasmic ratio remained below 1 (N-Cyt R < 1), sign of low nuclear activity. The RES and QRC induced apoptosis of Hep2 cells by increasing of oxidative stress markers, MDA, and by modulating detoxifying enzymes, CAT and SOD. Our study results prove antiproliferative and proapoptotic properties of quercetin and resveratrol with regard to larynx cancer.

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Resveratrol (RES) y quercetina (QRC), es un agente prometedor y relevante tanto para la quimioprevención como para el tratamiento del cáncer a través de varias vías de señalización, involucrado en su actividad anticancerígena relacionada con su potencial quimioterapéutico, asociado con la inducción de la generación de especies reactivas del oxígeno (ROS) en células cancerosas, lo que lleva a apoptosis. En nuestro estudio, hemos resumido los mecanismos de acción de RES y QRC, y sus implicaciones farmacológicas y posibles aplicaciones terapéuticas en la terapia del cáncer. Después del tratamiento de las células Hep 2 con QRC o RES, las vías de muerte, tal como la liberación de citocromo c, las vías ERK1/2 e IRS-1, se regulaban positivamente, mientras que la vía de supervivencia celular, incluida PI3K/AKT, se regulaba negativamente. El RES y el QRC provocaron oncosis, hipertrofia celular, hipercondensación de la cromatina, rotura de la membrana plasmática y nuclear y formación de cuerpos apoptóticos. Las mediciones morfométricas de algunos parámetros celulares y nucleares mostraron que RES y QRC indujeron un aumento en las células y el tamaño nuclear, la proporción nucleocitoplasmática se mantuvo por debajo de 1 (N- Cyt R <1), signo de baja actividad nuclear. RES y QRC indujeron la apoptosis de las células Hep2 aumentando los marcadores de estrés oxidativo, MDA, y modulando las enzimas desintoxicantes, CAT y SOD. Los resultados de nuestro estudio demuestran las propiedades antiproliferativas y proapoptóticas de la quercetina y el resveratrol con respecto al cáncer de laringe.

Assuntos

Humanos , Quercetina/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Resveratrol/farmacologia , Sobrevivência Celular , Morte Celular , Apoptose , Estresse Oxidativo , Proliferação de Células/efeitos dos fármacos

RESUMO

Chagas disease, caused by Trypanosoma cruzi (T. cruzi), is one of the most important neglected diseases in Latin America. The limited use of the current nitro-derivative-based chemotherapy highlights the need for alternative drugs and the identification of their molecular targets. In this study, we investigated the trypanocidal effect of the sesquiterpene lactone dehydroleucodine (DhL) and its derivatives, focusing on the antioxidative defense of the parasites. DhL and two derivatives, at lesser extent, displayed antiproliferative effect on the parasites. This effect was blocked by the reducing agent glutathione (GSH). Treated parasites exhibited increased intracellular ROS concentration and trypanothione synthetase activity, accompanied by mitochondrial swelling. Although molecular dynamics studies predicted that GSH would not interact with DhL, 1H-NMR analysis confirmed that GSH could protect parasites by interacting with the lactone. When parasites overexpressing mitochondrial tryparedoxin peroxidase were incubated with DhL, its effect was attenuated. Overexpression of cytosolic tryparedoxin peroxidase also provided some protection against DhL. These findings suggest that DhL induces oxidative imbalance in T. cruzi, offering new insights into potential drug targets against this parasite.

Assuntos

Lactonas , Espécies Reativas de Oxigênio , Sesquiterpenos , Trypanosoma cruzi , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/metabolismo , Sesquiterpenos/farmacologia , Lactonas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Tripanossomicidas/farmacologia , Glutationa/metabolismo , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Proteínas de Protozoários/metabolismo , Animais , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Amida Sintases

RESUMO

The objective were to evaluate the effects of supplementation of standardized dry extract of Rosmarinus officinalis (RO) and the application of aesthetic radiofrequency on the oxidative stress markers catalase (CAT), superoxide dismutase (SOD), non-protein thiols (NP-SH), and thiobarbituric acid reactive species (TBARS) and the biochemical markers triglycerides, total cholesterol, high density lipoprotein (HDL) cholesterol, glutamic-oxaloacetic transaminase (TGO/AST), pyruvic-glutamic transaminase (TGP/ALT), gamma glutamyl transpeptidase (gamma-GT), and creatinine. This study included 32 women received the aesthetic therapy to reduce localized fat. They were divided into the control group (n = 8) receiving placebo capsules and the intervention group (n = 24) subdivided into Group A, B, and C, each with eight members receiving supplementation with 100, 500, and 1000 mg/day of standardized dry extract of RO, respectively. The Universal Trial Number (UTN) - U1111-1274-6255. Supplementation with RO (500 mg/day) demonstrated a reduction in oxidative stress (quantified with through a significant increase in NP-SH and a reduction in SOD and CAT enzymes). The radiofrequency aesthetic treatment did not promote an increase in oxidative stress; however, it caused significant changes in total cholesterol, HDL cholesterol, and creatinine. RO is a plant with antioxidant effects and its oral consumption is safe in selected women subjects in hepatic and renal markers.

Assuntos

Suplementos Nutricionais , Estresse Oxidativo , Extratos Vegetais , Rosmarinus , Humanos , Feminino , Estresse Oxidativo/efeitos dos fármacos , Método Duplo-Cego , Rosmarinus/química , Adulto , Extratos Vegetais/farmacologia , Ondas de Rádio , Superóxido Dismutase/metabolismo , Superóxido Dismutase/sangue , Pessoa de Meia-Idade , Biomarcadores/sangue , Antioxidantes/farmacologia , Catalase/metabolismo , Catalase/sangue , Adulto Jovem

RESUMO

OBJECTIVE: The purpose of the present study was to examine the association of oxidative stress markers with sarcopenia in the general United States population under the age of 60. METHODS: We used the National Health and Nutrition Examination Survey data from 2011‒2014 and performed Restricted Cubic Spline (RCS) plots, weighted multivariable logistic regression analysis to calculate ratio ratios and 95% Confidence Intervals, and subgroup analysis based on age, sex, hypertension, diabetes mellitus, and body mass index stratification to determine the association of markers of oxidative stress with the prevalence of sarcopenia. RESULTS: The present analysis included a total of 8,782 participants. Firstly, the RCS plots showed a roughly L-shaped curve association of total bilirubin and serum iron with a prevalence of sarcopenia. Secondly, albumin was negatively and linearly associated with the risk of sarcopenia. Finally, with the increase in gamma-glutamyl transferase, the prevalence of sarcopenia showed a trend of first rising and then declining as a result of the iron increase. CONCLUSIONS: We demonstrated a nonlinear association between markers of oxidative stress and sarcopenia. The need to focus more on levels of oxidative stress in the body could provide better prevention strategies for sarcopenia.

Assuntos

Biomarcadores , Inquéritos Nutricionais , Estresse Oxidativo , Sarcopenia , Humanos , Estresse Oxidativo/fisiologia , Sarcopenia/epidemiologia , Sarcopenia/sangue , Feminino , Masculino , Biomarcadores/sangue , Prevalência , Pessoa de Meia-Idade , Adulto , Estados Unidos/epidemiologia , Fatores de Risco , Ferro/sangue , Índice de Massa Corporal , gama-Glutamiltransferase/sangue , Adulto Jovem , Bilirrubina/sangue , Estudos Transversais , Fatores Etários , Fatores Sexuais

RESUMO

Patients with sickle cell disease (SCD) display an overactive bladder (OAB). Intravascular hemolysis in SCD is associated with various severe SCD complications. However, no experimental studies have evaluated the effect of intravascular hemolysis on bladder function. This study aimed to assess the effects of intravascular hemolysis on the micturition process and the contractile mechanisms of the detrusor smooth muscle (DSM) in a mouse model with phenylhydrazine (PHZ)-induced hemolysis; furthermore, it aimed to investigate the role of intravascular hemolysis in the dysfunction of nitric oxide (NO) signaling and in increasing oxidative stress in the bladder. Mice underwent a void spot assay, and DSM contractions were evaluated in organ baths. The PHZ group exhibited increased urinary frequency and increased void volumes. DSM contractile responses to carbachol, KCl, α-ß-methylene-ATP, and EFS were increased in the PHZ group. Protein expression of phosphorylated endothelial NO synthase (eNOS) (Ser-1177), phosphorylated neuronal NO synthase (nNOS) (Ser-1417), and phosphorylated vasodilator-stimulated phosphoprotein (VASP) (Ser-239) decreased in the bladder of the PHZ group. Protein expression of oxidative stress markers, NOX-2, 3-NT, and 4-HNE, increased in the bladder of the PHZ group. Our study shows that intravascular hemolysis promotes voiding dysfunction correlated with alterations in the NO signaling pathway in the bladder, as evidenced by reduced levels of p-eNOS (Ser-1177), nNOS (Ser-1417), and p-VASP (Ser-239). The study also showed that intravascular hemolysis increases oxidative stress in the bladder. Our study indicates that intravascular hemolysis promotes an OAB phenotype similar to those observed in patients and mice with SCD.

RESUMO

BACKGROUND: This study evaluated the effects of concurrent isolated training (T) or training combined with the antioxidant N-acetylcysteine (NAC) on cardiac remodeling and oxidative stress in spontaneously hypertensive rats (SHR). METHODS: Six-month-old male SHR were divided into sedentary (S, n = 12), concurrent training (T, n = 13), sedentary supplemented with NAC (SNAC, n = 13), and concurrent training with NAC supplementation (TNAC, n = 14) groups. T and TNAC rats were trained three times a week on a treadmill and ladder; NAC supplemented groups received 120 mg/kg/day NAC in rat chow for eight weeks. Myocardial antioxidant enzyme activity and lipid hydroperoxide concentration were assessed by spectrophotometry. Gene expression of NADPH oxidase subunits Nox2, Nox4, p22 phox, and p47 phox was evaluated by real time RT-PCR. Statistical analysis was performed using ANOVA and Bonferroni or Kruskal-Wallis and Dunn. RESULTS: Echocardiogram showed concentric remodeling in TNAC, characterized by increased relative wall thickness (S 0.40 ± 0.04; T 0.39 ± 0.03; SNAC 0.40 ± 0.04; TNAC 0.43 ± 0.04 *; * p < 0.05 vs T and SNAC) and diastolic posterior wall thickness (S 1.50 ± 0.12; T 1.52 ± 0.10; SNAC 1.56 ± 0.12; TNAC 1.62 ± 0.14 * mm; * p < 0.05 vs T), with improved contractile function (posterior wall shortening velocity: S 39.4 ± 5.01; T 36.4 ± 2.96; SNAC 39.7 ± 3.44; TNAC 41.6 ± 3.57 * mm/s; * p < 0.05 vs T). Myocardial lipid hydroperoxide concentration was lower in NAC treated groups (S 210 ± 48; T 182 ± 43; SNAC 159 ± 33 *; TNAC 110 ± 23 *# nmol/g tissue; * p < 0.05 vs S, # p < 0.05 vs T and SNAC). Nox 2 and p22 phox expression was higher and p47 phox lower in T than S [S 1.37 (0.66-1.66); T 0.78 (0.61-1.04) *; SNAC 1.07 (1.01-1.38); TNAC 1.06 (1.01-1.15) arbitrary units; * p < 0.05 vs S]. NADPH oxidase subunits did not differ between TNAC, SNAC, and S groups. CONCLUSION: N-acetylcysteine supplementation alone reduces oxidative stress in untreated spontaneously hypertensive rats. The combination of N-acetylcysteine and concurrent exercise further decreases oxidative stress. However, the lower oxidative stress does not translate into improved cardiac remodeling and function in untreated spontaneously hypertensive rats.

Assuntos

Acetilcisteína , Hipertensão , NADPH Oxidases , Estresse Oxidativo , Ratos Endogâmicos SHR , Remodelação Ventricular , Animais , Masculino , Estresse Oxidativo/efeitos dos fármacos , Acetilcisteína/farmacologia , Remodelação Ventricular/efeitos dos fármacos , Hipertensão/fisiopatologia , Hipertensão/tratamento farmacológico , Hipertensão/metabolismo , NADPH Oxidases/metabolismo , NADPH Oxidases/genética , Ratos , Antioxidantes/farmacologia , Condicionamento Físico Animal , Modelos Animais de Doenças , NADPH Oxidase 2/metabolismo , NADPH Oxidase 2/genética , NADPH Oxidase 4/metabolismo , NADPH Oxidase 4/genética , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética , Miocárdio/metabolismo , Miocárdio/patologia , Peróxidos Lipídicos/metabolismo , Função Ventricular Esquerda/efeitos dos fármacos , Suplementos Nutricionais , Hipertrofia Ventricular Esquerda/fisiopatologia , Hipertrofia Ventricular Esquerda/prevenção & controle , Hipertrofia Ventricular Esquerda/metabolismo

RESUMO

Varicocele can reduce male fertility potential through various oxidative stress mechanisms. Excessive production of reactive oxygen species may overwhelm the sperm's defenses against oxidative stress, damaging the sperm chromatin. Sperm DNA fragmentation, in the form of DNA strand breaks, is recognized as a consequence of the oxidative stress cascade and is commonly found in the ejaculates of men with varicocele and fertility issues. This paper reviews the current knowledge regarding the association between varicocele, oxidative stress, sperm DNA fragmentation, and male infertility, and examines the role of varicocele repair in alleviating oxidative-sperm DNA fragmentation in these patients. Additionally, we highlight areas for further research to address knowledge gaps relevant to clinical practice.

Assuntos

Fragmentação do DNA , Infertilidade Masculina , Estresse Oxidativo , Espermatozoides , Varicocele , Humanos , Masculino , Varicocele/fisiopatologia , Varicocele/complicações , Estresse Oxidativo/fisiologia , Infertilidade Masculina/etiologia , Infertilidade Masculina/genética , Infertilidade Masculina/fisiopatologia , Infertilidade Masculina/metabolismo , Espermatozoides/fisiologia , Espermatozoides/metabolismo , Espécies Reativas de Oxigênio/metabolismo

RESUMO

Studies have shown that deficiencies in magnesium, selenium, and zinc in individuals with obesity compromise the endogenous antioxidant defense system. This study aimed to evaluate the impact of mineral deficiency on enzymatic antioxidant defense in women with obesity. The study involved 63 women with obesity (BMI ≥ 35 kg/m2) and 77 eutrophic women (BMI between 18.5 and 24.9 kg/m2). Variables such as fasting glucose, glycated hemoglobin, fasting insulin, and serum lipids were analyzed. Insulin resistance was measured using the homeostasis assessment model (HOMA-IR) and beta cell function using the homeostasis assessment model (HOMA-ß). Dietary intake of energy, macronutrients (including magnesium, zinc, and selenium), and plasma, erythrocyte, and urinary concentrations of these minerals were measured and analyzed. Serum cortisol, plasma leptin, plasma thiobarbituric acid reactive substances, and the activity of erythrocyte superoxide dismutase (SOD), erythrocyte glutathione peroxidase (GPX), and erythrocyte catalase were also analyzed. Women with obesity had reduced plasma and erythrocyte concentrations and greater urinary excretion of all minerals compared to normal weight women (p < 0.05). There was a positive association between erythrocyte concentrations of zinc and selenium and the activity of the GPX and SOD enzymes in erythrocytes in women with obesity (p < 0.05), in addition to a positive association between serum insulin and the enzyme GPX, which is dependent on dietary selenium (p < 0.05). Individuals with obesity are deficient in magnesium, selenium, and zinc, which appears to impair the antioxidant defense system and contribute to important metabolic disorders such as oxidative stress in these patients.

RESUMO

OBJECTIVES: To investigate the effects of a Brazil nut-enriched diet on the wall thickness and the left ventricular chamber diameter of the heart, and lipid peroxidation in a CKD-induced model. METHODS: Male Wistar rats at 12 weeks of age were divided into two groups (n=16/group): the Nx group, which underwent 5/6 nephrectomy, and the Sham group, as a control. After 5 weeks, the groups were subdivided according to diet (n=8/group): the Nx and Sham groups received a control diet; the Nx5% and Sham5% groups received a diet enriched with 5 % Brazil nuts for 8 weeks. The left ventricular thickening and chamber diameter were determined. Plasma biochemical parameters were evaluated. Analysis of thiobarbituric acid reactive substances (TBARS) and antioxidant enzyme activity was performed in the plasma and the left ventricle (LV). LV mRNA expression of nuclear factor-kappa B (NF-κB) and nuclear factor erythroid 2-related factor 2 (Nrf2) was evaluated by reverse transcription-polymerase chain reaction. RESULTS: The Nx5% group showed a remodeled LV wall with decreased thickness compared to the Nx group (p=0.016). Furthermore, LV TBARS concentration was reduced in the Nx5% group (p=0.0064). In addition, the Nx5% group showed an increase in plasma GPx activity (p=0.0431). No significant results were found concerning the LV mRNA expression of NF-κB and Nrf2 genes. CONCLUSIONS: A Brazil nut-enriched diet decreased LV thickness and LV TBARS concentration and increased GPx activity in a 5/6 nephrectomy experimental model, making it a promising adjuvant therapy to improve antioxidant status and cardiovascular outcomes in chronic kidney disease.