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OBJECTIVE: To evaluate the efficacy and cytotoxicity of experimental 6% and 35% hydrogen peroxide gels (HP6 or HP35) incorporated with titanium dioxide nanoparticles (NP) co-doped with nitrogen and fluorine and irradiated with a violet LED light (LT). METHODS: Bovine enamel-dentin disks adapted to artificial pulp chambers were randomly assigned to bleaching (n = 8/group): NC (negative control), NP, HP6, HP6 + LT, HP6 + NP, HP6 + NP + LT, HP35, HP35 + LT, HP35 + NP, HP35 + NP + LT, and commercial HP35 (COM). Color (ΔE00) and whiteness index (ΔWID) changes were measured before and 14 days after bleaching. The extracts (culture medium + diffused gel components) collected after the first session were applied to odontoblast-like MDPC-23 cells, which were assessed concerning their viability, oxidative stress, and morphology. The amount of HP diffused through the disks was determined. Data were analyzed by generalized linear models or Kruskal Wallis Tests (α = 5%). RESULTS: HP6 + NP + LT exhibited ΔE00 and ΔWID higher than HP6 (p < 0.05) and similar to all HP35 groups. HP6 + NP + LT showed the lowest HP diffusion, and the highest cell viability (%) among bleached groups, preserving cell morphology and number of living cells similar to NC and NP. HP6 + LT, HP6 + NP, and HP6 + NP + LT exhibited the lowest cell oxidative stress among bleached groups (p < 0.05). HP35, HP35 + LT, and HP35 (COM) displayed the lowest cell viability. CONCLUSION: HP6 achieved significantly higher color and whiteness index changes when incorporated with nanoparticles and light-irradiated and caused lower cytotoxicity than HP35 gels. The nanoparticles significantly increased cell viability and reduced the hydrogen peroxide diffusion and oxidative stress, regardless of HP concentration. CLINICAL SIGNIFICANCE: Incorporation of co-doped titanium dioxide nanoparticles combined with violet irradiation within the HP6 gel could promote a higher perceivable and acceptable efficacy than HP6 alone, potentially reaching the optimal esthetic outcomes rendered by HP35. This approach also holds the promise of reducing cytotoxic damages and, consequently, tooth sensitivity.
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Supervivencia Celular , Geles , Peróxido de Hidrógeno , Nanopartículas , Titanio , Blanqueadores Dentales , Blanqueamiento de Dientes , Peróxido de Hidrógeno/farmacología , Peróxido de Hidrógeno/toxicidad , Blanqueamiento de Dientes/métodos , Titanio/química , Titanio/toxicidad , Animales , Bovinos , Blanqueadores Dentales/toxicidad , Blanqueadores Dentales/farmacología , Supervivencia Celular/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Técnicas In Vitro , Odontoblastos/efectos de los fármacos , Esmalte Dental/efectos de los fármacos , Distribución Aleatoria , Dentina/efectos de los fármacosRESUMEN
A feature in neurodegenerative disorders is the loss of neurons, caused by several factors including oxidative stress induced by reactive oxygen species (ROS). In this work, static magnetic field (SMF) was applied in vitro to evaluate its effect on the viability, proliferation, and migration of human neuroblastoma SH-SY5Y cells, and on the toxicity induced by hydrogen peroxide (H2O2), tert-butyl hydroperoxide (tBHP), H2O2/sodium azide (NaN3) and photosensitized oxidations by photodynamic therapy (PDT) photosensitizers. The SMF increased almost twofold the cell expression of the proliferation biomarker Ki-67 compared to control cells after 7 days of exposure. Exposure to SMF accelerated the wound healing of scratched cell monolayers and significantly reduced the H2O2-induced and the tBHP-induced cell deaths. Interestingly, SMF was able to revert the effects of NaN3 (a catalase inhibitor), suggesting an increased activity of catalase under the influence of the magnetic field. In agreement with this hypothesis, SMF significantly reduced the oxidation of DCF-H2, indicating a lower level of intracellular ROS. When the redox imbalance was triggered through photosensitized oxidation, no protection was observed. This observation aligns with the proposed role of catalase in cellular proctetion under SMF. Exposition to SMF should be further validated in vitro and in vivo as a potential therapeutic approach for neurodegenerative disorders.
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Neuroblastoma , Enfermedades Neurodegenerativas , Humanos , Especies Reactivas de Oxígeno/metabolismo , Peróxidos/farmacología , Peróxido de Hidrógeno/toxicidad , Línea Celular Tumoral , Catalasa/metabolismo , Neuroblastoma/metabolismo , Estrés Oxidativo , Campos MagnéticosRESUMEN
In pulmonary fibrosis, the proliferation of fibroblasts and their differentiation into myofibroblasts is often caused by tissue damage, such as oxidative damage caused by reactive oxygen species, which leads to progressive rupture and thus destruction of the alveolar architecture, resulting in cell proliferation and tissue remodeling. Bezafibrate (BZF) is an important member of the peroxisome proliferator-activated receptor (PPARs) family agonists, used in clinical practice as antihyperlipidemic. However, the antifibrotic effects of BZF are still poorly studied. The objective of this study was to evaluate the effects of BZF on pulmonary oxidative damage in lung fibroblast cells. MRC-5 cells were treated with hydrogen peroxide (H2O2) to induce oxidative stress activation and BZF treatment was administered at the same moment as H2O2 induction. The outcomes evaluated were cell proliferation and cell viability; oxidative stress markers such as reactive oxygen species (ROS), catalase (CAT) levels and thiobarbituric acid reactive substances (TBARS); col-1 and α-SMA mRNA expression and cellular elasticity through Young's modulus analysis evaluated by atomic force microscopy (AFM). The H2O2-induced oxidative damage decreased the cell viability and increased ROS levels and decreased CAT activity in MRC-5 cells. The expression of α-SMA and the cell stiffness increased in response to H2O2 treatment. Treatment with BZF decreased the MRC-5 cell proliferation, ROS levels, reestablished CAT levels, decreased the mRNA expression of type I collagen protein (col-1) and α-smooth muscle actin (α-SMA), and cellular elasticity even with H2O2 induction. Our results suggest that BZF has a potential protective effect on H2O2-induced oxidative stress. These results are based on an in vitro experiment, derived from a fetal lung cell line and may emerge as a possible new therapy for the treatment of pulmonary fibrosis.
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Peróxido de Hidrógeno , Fibrosis Pulmonar , Humanos , Peróxido de Hidrógeno/toxicidad , Peróxido de Hidrógeno/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Bezafibrato/farmacología , Bezafibrato/metabolismo , Fibrosis Pulmonar/patología , Pulmón/metabolismo , Estrés Oxidativo , Fibroblastos , ARN Mensajero/metabolismoRESUMEN
OBJECTIVES: The development of new bleaching agents with minimum concentration of hydrogen peroxide (HP), without adverse effects, and with bleaching effectiveness, has great clinical relevance. The aim of this study was to evaluate the bleaching efficacy and cytotoxicity of a new niobium-based bleaching gel, compared to already available HP-based gels. MATERIALS AND METHODS: For the bleaching efficacy analysis, 40 bovine incisors were randomly divided into 4 groups according to the established bleaching protocol: control, untreated; 35HP, 35% HP bleaching gel; 6HP, 6% HP bleaching gel; NbHP, niobium gel associated with 3% HP gel. The color variation was measured in a spectrophotometer and the values of ΔL, Δa, Δb, and ΔE obtained. For the cell viability assay by MTT, MC3T3 cells were exposed to bleaching gel extracts (1:500, 1:250, 1:125 dilutions; immediately and 24 h). Statistical tests were performed (P < 0.05). RESULTS: The color alteration for all bleaching gels was significant compared to control (P < 0.05), but the NbHP gel showed a significant ΔE than other gels, with expressive color alteration at 14 days (P < 0.05). The 35HP showed high cytotoxicity regarding control and the most groups in all periods and extracts analyzed (P < 0.05), while the NbHP showed greater cell viability than control in the immediate period, dilution of the 1:500 and superior to 6HP in the most extracts at 24 h. CONCLUSION: The new experimental niobium-based gel has bleaching efficacy similar to that of gels with a high concentration of HP, and it has high cytocompatibility. CLINICAL RELEVANCE: The use of this new generation of niobium-based whitening gel associated with a low concentration of hydrogen peroxide represents the possibility of a tooth whitening with lower dentin sensitivity.
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Blanqueadores Dentales , Blanqueamiento de Dientes , Animales , Bovinos , Geles , Peróxido de Hidrógeno/toxicidad , Niobio/toxicidad , Blanqueadores Dentales/toxicidadRESUMEN
OBJECTIVES: Evaluating the effects of rosmarinic (RA) and cryptochlorogenic (CGA) acids isolated from Blechnum binervatum extract on stem cell viability, toxicity and the protective effect on oxidative cell damage. METHODS: MTT and LDH methods were employed, using stem cells from teeth. RA and CGA were evaluated at 100, 250 and 500 µM. The negative effect of hydrogen peroxide (H2O2) (200-2200 µM) and the capacity of RA and CGA (10-100 µM) as protective agents were also evaluated. DAPI followed by fluorescent microscopy was employed to photograph the treated and untreated cells. KEY FINDINGS: At all tested concentrations, RA and CGA demonstrated the ability to maintain cell viability, and with no cytotoxic effects on the treated stem cells. RA also induced an increase of the cell viability and a reduction in cytotoxicity. H2O2 (1400 µM) induced >50% of cytotoxicity, and both compounds were capable of suppressing H2O2 damage, even at the lowest concentration. At 100 µM, in H2O2 presence, total cell viability was observed through microscope imaging. CONCLUSIONS: These findings contribute to the continued research into natural substances with the potential for protecting cells against oxidative injury, with the consideration that RA and CGA are useful in the regeneration of damaged stem cells.
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Helechos , Peróxido de Hidrógeno , Peróxido de Hidrógeno/toxicidad , Ácido Clorogénico/farmacología , Estrés Oxidativo , Supervivencia Celular , Células MadreRESUMEN
This paper aimed to assess the influence of adhesive restoration interface on the diffusion of hydrogen peroxide (H2O2), indirect toxicity, and pro-inflammatory mediators expression by odontoblast-like cells, after in-office tooth whitening. Dental cavities prepared in bovine enamel/dentin discs were adhesively restored and subjected or not to hydrolytic degradation (HD). A whitening gel with 35% H2O2 (WG) was applied for 45 min onto restored and non-restored specimens adapted to artificial pulp chambers giving rise to the groups: SD- intact discs (control); SD/HP- whitened intact discs; RT/HP- restored and whitened discs; and RT/HD/HP- restored and whitened discs subjected to HD. The extracts (culture medium + WG components diffused through enamel/dentin/restoration interface) were collected and applied to odontoblast-like MDPC-23 cells. The study evaluated the amount of H2O2 in the extracts, as well as the cell viability (CV), cell morphology (CM), and gene expression of inflammatory mediators (TNF-α and COX-2) by the pulp cells exposed to the extracts (ANOVA and Tukey tests; 5% significance). All whitened groups presented lower CV than SD (control; p<0.05). The highest CV reduction and gene expression of TNF-α and COX-2 was observed in the RT/HD/HP group in comparison with SD/HP and RT/HP (control; p<0.05). CM alterations occurred in all whitened groups. The intensity of these cell side effects was directly related with the amount of H2O2 in the extracts. We concluded that adhesive restoration of dental cavity increases the H2O2 diffusion after in-office whitening, enhancing the indirect toxicity of this therapy and trigger pro-inflammatory overexpression by MDPC-23 cells.
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Blanqueadores Dentales , Blanqueamiento de Dientes , Animales , Bovinos , Ciclooxigenasa 2 , Esmalte Dental , Peróxido de Hidrógeno/toxicidad , Mediadores de Inflamación , Blanqueadores Dentales/toxicidad , Factor de Necrosis Tumoral alfaRESUMEN
Mitochondria are a primary source and a target of reactive oxygen species (ROS). Increased mitochondrial production of ROS is associated with bioenergetics decline, cell death, and inflammation. Here we investigated whether a pretreatment (for 24 h) with sesamol (SES; at 12.5-50 µM) would be efficient in preventing the mitochondrial collapse induced by hydrogen peroxide (H2O2, at 300 µM) in the human neuroblastoma SH-SY5Y cell line. We have found that a pretreatment with SES at 25 µM decreased the effects of H2O2 on lipid peroxidation, protein carbonylation, and protein nitration in membranes obtained from the mitochondria isolated from the SH-SY5Y cells. In this regard, SES pretreatment decreased the production of superoxide anion radical (O2-â¢) by the mitochondria of H2O2-treated cells. SES also prevented the mitochondrial dysfunction induced by H2O2, as assessed by analyzing the activity of the complexes I and V. The H2O2-induced reduction in the production of adenosine triphosphate (ATP) was also prevented by SES. The levels of the pro-inflammatory cytokines interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α), as well as the activity of the transcription factor nuclear factor-κB (NF-κB) were downregulated by the SES pretreatment in the H2O2-challenged cells. Silencing of the nuclear factor erythroid 2-related factor 2 (Nrf2) transcription factor abolished the protection induced by SES regarding mitochondrial function and inflammation. Thus, SES depends on Nrf2 to promote mitochondrial protection in cells facing redox impairment.
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Factor 2 Relacionado con NF-E2 , Neuroblastoma , Benzodioxoles , Línea Celular Tumoral , Supervivencia Celular , Humanos , Peróxido de Hidrógeno/metabolismo , Peróxido de Hidrógeno/toxicidad , Mitocondrias/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Neuroblastoma/metabolismo , Fenoles , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Ferulic acid (FA) is a phenolic compound that has antioxidant, anti-inflammatory and anticarcinogenic properties besides presenting cytoprotective activity. It has limited oral bioavailability what is a challenge to its therapeutic application. In this way, this investigation aimed to develop FA-loaded nanocapsule suspensions (NC-FA) prepared with ethylcellulose and evaluate their in vitro release profile, mucoadhesion and irritation potential; scavenging capacity, cytotoxicity, cytoprotection and genoprotection against hydrogen peroxide-induced damage in hMNC (human Mononucleated Cells) culture. The nanocapsules presented physicochemical characteristics compatible with colloidal systems (NC-FA: 112 ± 3 nm; NC-B (without FA): 107 ± 3 nm; PdI < 0.2; Span<2.0 and negative zeta potential). In addition, the nanoparticulate system promoted the FA controlled release, increasing the half-life twice through the in vitro dialysis method. NC-FA and NC-B were able to interact with mucin, which is an indicative of mucoadhesive properties and the association of FA with nanocapsules showed decreased irritation by HET-CAM method. Besides, the NC-FA did not present cytotoxicity in hMNC and improved the ATBS radical scavenging capacity. Besides, it prevented, treated and reversed oxidative conditions in a H2O2-induced model in hMNC. Thus, this nanocarrier formulation is promising to perform more preclinical investigations focusing on diseases involving oxidative mechanisms.
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Antioxidantes/administración & dosificación , Ácidos Cumáricos/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Nanocápsulas/química , Animales , Antioxidantes/farmacocinética , Antioxidantes/farmacología , Células Cultivadas , Celulosa/análogos & derivados , Embrión de Pollo , Ácidos Cumáricos/farmacocinética , Ácidos Cumáricos/farmacología , Humanos , Peróxido de Hidrógeno/toxicidad , Irritantes , Linfocitos , Mucinas , Nanocápsulas/efectos adversosRESUMEN
Endophytic fungi are promising sources of bioactive substances; however, their secondary metabolites are toxic to plants, animals, and humans. This study aimed toevaluate the toxic, cytotoxic, mutagenic and oxidant/antioxidant activities of acetonitrile extract (AEPc), citrinin (CIT) and dicitrinin-A (DIC-A) of Penicillium citrinum. For this, the test substances at 0.5; 1.0; 1.5 and 2 µg/mLwere exposed for 24 and 48 h in Artemia salina, and 48 h in Allium cepa test systems. The oxidant/antioxidant test was evaluated in pre-, co- and post-treatment with the stressor hydrogen peroxide (H2O2) in Saccharomyces cerevisiae. The results suggest that the AEPc, CIT and DIC-A at 0.5; 1.0; 1.5 and 2 µg/mL showed toxicity in A. saline, with LC50 (24 h) of 2.03 µg/mL, 1.71 µg/mL and 2.29 µg/mL, and LC50 (48 h) of 0.51 µg/mL, 0.54 µg/mL and 0.54 µg/mL, respectively.In A. cepa, the test substances also exerted cytotoxic and mutagenic effects. The AEPc, CIT and DIC-A at lower concentrations modulated the damage induced by H2O2 in the proficient and mutant strains of S. cerevisiae for cytoplasmic and mitochondrial superoxide dismutase. Moreover, the AEPc at 2 µg/mL and CIT at the two highest concentrations did not affect the H2O2-induced DNA damage in the test strains. In conclusion, AEPc, CIT and DIC-A of P. citrinum may exert their toxic, cytotoxic and mutagenic effects in the test systems possibly through oxidative stress induction pathway.
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Citrinina , Acetonitrilos/toxicidad , Animales , Citrinina/toxicidad , Humanos , Peróxido de Hidrógeno/toxicidad , Penicillium , Extractos Vegetales/toxicidad , Saccharomyces cerevisiae/genéticaRESUMEN
Cellular senescence is more than a proliferative arrest in response to various stimuli. Senescent cells (SC) participate in several physiological processes, and their adequate removal is essential to maintain tissue and organism homeostasis. However, SC accumulation in aging and age-related diseases alters the tissue microenvironment leading to deterioration. The immune system clears the SC, but the specific scenarios and mechanisms related to recognizing and eliminating them are unknown. Hence, we aimed to evaluate the existence of three regulatory signals of phagocytic function, CD47, major histocompatibility complex class I (MHC-I), and calreticulin, present in the membrane of SC. Therefore, primary fibroblasts were isolated from CD1 female mice lungs, and stress-induced premature senescence (SIPS) was induced with hydrogen peroxide. Replicative senescence (RS) was used as a second senescent model. Our results revealed a considerable increment of CD47 and MHC-I in RS and SIPS fibroblasts. At the same time, no significant changes were found in calreticulin, suggesting that those signals might be associated with evading immune system recognition and thus averting senescent cells clearance.
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Antígenos CD1/metabolismo , Antígeno CD47/metabolismo , Senescencia Celular/fisiología , Fibroblastos/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Pulmón/metabolismo , Animales , Calbindina 2/metabolismo , Senescencia Celular/efectos de los fármacos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Femenino , Fibroblastos/citología , Peróxido de Hidrógeno/toxicidad , Ratones , Cultivo Primario de CélulasRESUMEN
Las quemaduras químicas en cuero cabelludo, que se producen en lugares públicos como salones de belleza o peluquerías causadas por mezclas de sustancias activas como persulfatos y peróxido de hidrógeno, secundarias a la decoloración de cabellos, producen graves secuelas de alopecias en pacientes jóvenes. Se trata de un caso clínico, de quemadura química, espesor completo, extensa, en cuero cabelludo. Productos utilizados en forma cotidiana en salones de belleza, peluquerías o domicilios, que tiene estrecha relación con el daño. Resolución del caso con colgajos locales, con tiempos de internación y quirúrgicos cortos, en tiempos de COVID. Enfoque de la falta de control de sustancias usadas en peluquerías, pocos casos publicados y secuelas psicosociales importantes, con pronta mejoría de calidad de vida y reinserción social
Chemical burns in scalp after hair bleaching are produced in public places such as hairdressing salons and are caused by the combination of active agents like persulfate and hydrogen peroxide. The burns leave severe sequels of alopecia in young patients. This is about a clinical case of a chemical burn in the sculp which is full thickness and has a great large. Products used on a daily basis in hairdressing salons or in the domiciles have a close connection with the hurt. In times of COVID the case was resolved with local flaps, and short period of hospitalization and surgical. Focus on the lack of control in the usage of substances made by hairdressing salons, the existence of few published cases and the main psychosocial sequels, a speedy recovery in the quality of life and social reintegration
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Humanos , Adulto , Control de Calidad , Cuero Cabelludo/anatomía & histología , Cuero Cabelludo/lesiones , Cirugía Plástica/métodos , Quemaduras Químicas/terapia , Expansión de Tejido , Trasplante de Piel/rehabilitación , Límite Permisible de Riesgos Laborales/prevención & control , Peróxido de Hidrógeno/toxicidadRESUMEN
Parachartergus fraternus wasp induces inflammation with a predominance of mononuclear cells, that can acquire macrophage functions at the sting site, amplifying the response. These cells can be activated by venomous animals and are involved in destruction of injurious agents and release of inflammatory mediators. The objective of this work was to evaluate the activity of P. fraternus venom (Pfv) on isolated murine macrophage function. The cells were obtained from peritoneal cavity of Swiss male mice and incubated with Pfv (2.5, 5 and 10 µg/mL). Cytotoxicity was determined using MTT assay. Adhesion and detachment were evaluated using violet crystal dye. Spreading was evaluated based on morphological parameters. Phagocytosis was performed with opsonized zymosan. Production of hydrogen peroxide (H2O2) and nitric oxide (NO) were quantified using the phenol red and Griess assays, respectively. Pfv at concentrations evaluated was not cytotoxic in MTT assay and did not cause macrophage detachment in cell culture plates. However, it increased adhesion of macrophage, spreading and phagocytosis of opsonized zymosan, as well as induced production of H2O2 and NO. Therefore, Pfv induces macrophage activation in vitro and the response of these cells can be correlated with the previously reported inflammatory process triggered by this wasp.
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Activación de Macrófagos , Avispas , Animales , Peróxido de Hidrógeno/toxicidad , Macrófagos Peritoneales , Masculino , Ratones , Óxido Nítrico , Fagocitosis , PonzoñasRESUMEN
The mitochondria are the major source of reactive species in the mammalian cells. Hydrogen peroxide (H2O2) is a potent inducer of redox impairment by a mechanism, at least in part, dependent on its ability to impair mitochondrial function. H2O2 plays an important role in several pathological conditions, including neurodegeneration and cardiovascular diseases. Astaxanthin (AST) is a xanthophyll that may be found in microalgae, crustaceans, and salmon and exhibits antioxidant and anti-inflammatory effects in different cell types. Even though there is evidence pointing to a role for AST as mitochondrial protectant agent, it was not clearly demonstrated how this xanthophyll attenuates mitochondrial stress. Therefore, we investigated here whether and how AST would be able to prevent the H2O2-induced mitochondrial dysfunction in the human neuroblastoma SH-SY5Y cells. We found that AST (20 µM) prevented the H2O2-induced loss of mitochondrial membrane potential (MMP) and decrease in the activity of the Complexes I and V. AST pretreatment blocked the mitochondria-related pro-apoptotic effects elicited by H2O2. AST upregulated the enzyme heme oxygenase-1 (HO-1) and the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) by a mechanism dependent on the phosphoinositide 3-kinase/Akt (PI3K/Akt) signaling pathway. Inhibition of the PI3K/Akt or of the HO-1 enzyme abolished the AST-induced mitochondrial protection in cells challenged with H2O2. Silencing of Nrf2 caused similar effects. Thus, we suggest that AST promotes mitochondrial protection by a mechanism dependent on the PI3K/Akt/Nrf2/HO-1 signaling pathway in SH-SY5Y cells exposed to H2O2.
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Hemo-Oxigenasa 1/metabolismo , Peróxido de Hidrógeno/toxicidad , Mitocondrias/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Relación Dosis-Respuesta a Droga , Fibrinolíticos/farmacología , Hemo-Oxigenasa 1/antagonistas & inhibidores , Humanos , Mitocondrias/efectos de los fármacos , Factor 2 Relacionado con NF-E2/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Xantófilas/farmacologíaRESUMEN
Extensive data have reported the involvement of oxidative stress in the pathogenesis of neuropsychiatric disorders, prompting the pursuit of antioxidant molecules that could become adjuvant pharmacological agents for the management of oxidative stress-associated disorders. The 3-[(4-chlorophenyl)selanyl]-1-methyl-1H-indole (CMI) has been reported as an antioxidant and immunomodulatory compound that improves depression-like behavior and cognitive impairment in mice. However, the exact effect of CMI on specific brain cells is yet to be studied. In this context, the present study aimed to evaluate the antioxidant activity of CMI in H2O2-induced oxidative stress on human dopaminergic neuroblastoma cells (SH-SY5Y) and to shed some light into its possible mechanism of action. Our results demonstrated that the treatment of SH-SY5Y cells with 4 µM CMI protected them against H2O2 (343 µM)-induced oxidative stress. Specifically, CMI prevented the increased number of reactive oxygen species (ROS)-positive cells induced by H2O2 exposure. Furthermore, CMI treatment increased the levels of reduced glutathione in SH-SY5Y cells. Molecular docking studies demonstrated that CMI might interact with enzymes involved in glutathione metabolism (i.e., glutathione peroxidase and glutathione reductase) and H2O2 scavenging (i.e., catalase). In silico pharmacokinetics analysis predicted that CMI might be well absorbed, metabolized, and excreted, and able to cross the blood-brain barrier. Also, CMI was not considered toxic overall. Taken together, our results suggest that CMI protects dopaminergic neurons from H2O2-induced stress by lowering ROS levels and boosting the glutathione system. These results will facilitate the clinical application of CMI to treat nervous system diseases associated with oxidative stress.
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Peróxido de Hidrógeno/toxicidad , Indoles/farmacología , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Compuestos de Selenio/farmacología , Dominio Catalítico , Línea Celular Tumoral , Glutatión/metabolismo , Glutatión Transferasa/química , Glutatión Transferasa/metabolismo , Humanos , Indoles/química , Indoles/metabolismo , Indoles/farmacocinética , Simulación del Acoplamiento Molecular , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/metabolismo , Fármacos Neuroprotectores/farmacocinética , Oxidorreductasas/química , Oxidorreductasas/metabolismo , Unión Proteica , Especies Reactivas de Oxígeno/metabolismo , Compuestos de Selenio/química , Compuestos de Selenio/metabolismo , Compuestos de Selenio/farmacocinéticaRESUMEN
KEY MESSAGE: H2O2 priming reprograms essential proteins' expression to help plants survive, promoting responsive and unresponsive proteins adjustment to salt stress. ABSTACRT: Priming is a powerful strategy to enhance abiotic stress tolerance in plants. Despite this, there is scarce information about the mechanisms induced by H2O2 priming for salt stress tolerance, particularly on proteome modulation. Improving maize cultivation in areas subjected to salinity is imperative for the local economy and food security. Thereby, this study aimed to investigate physiological changes linked with post-translational protein events induced by foliar H2O2 priming of Zea mays plants under salt stress. As expected, salt treatment promoted a considerable accumulation of Na+ ions, a 12-fold increase. It drastically affected growth parameters and relative water content, as well as promoted adverse alteration in the proteome profile, when compared to the absence of salt conditions. Conversely, H2O2 priming was beneficial via specific proteome reprogramming, which promoted better response to salinity by 16% reduction in Na+ content and shoots growth improvement, increasing 61% in dry mass. The identified proteins were associated with photosynthesis and redox homeostasis, critical metabolic pathways for helping plants survive in saline stress by the protection of chloroplasts organization and carbon fixation, as well as state redox. This research provides new proteomic data to improve understanding and forward identifying biotechnological strategies to promote salt stress tolerance.
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Peróxido de Hidrógeno/toxicidad , Proteómica , Estrés Salino/efectos de los fármacos , Zea mays/fisiología , Malondialdehído/metabolismo , Fenotipo , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Proteínas de Plantas/metabolismo , Potasio/metabolismo , Proteoma/metabolismo , Sodio/metabolismo , Agua , Zea mays/efectos de los fármacos , Zea mays/crecimiento & desarrolloRESUMEN
Previous preclinical studies have demonstrated that cannabidiol (CBD) and cannabigerol (CBG), two non-psychotomimetic phytocannabinoids from Cannabis sativa, induce neuroprotective effects on toxic and neurodegenerative processes. However, a comparative study of both compounds has not been reported so far, and the targets involved in this effect remain unknown. The ability of CBD and CBG to attenuate the neurotoxicity induced by two insults involving oxidative stress (hydrogen peroxide, H2O2) and mitochondrial dysfunction (rotenone) was evaluated in neural cell cultures. The involvement of CB-1 and CB-2 or 5-HT1A receptors was investigated. The neuroprotective effect of their respective acids forms, cannabidiolic acid (CBDA) and cannabigerolic acid (CBGA), was also analyzed. MTT and immunocytochemistry assays were used to evaluate cell viability. No significant variation on cell viability was per se induced by the lower concentrations tested of CBD and CBG or CBDA and CBGA; however, high concentrations of CBD, CBDA, or CBGA were toxic since a 40-50% reduction of cell viability was observed. CBD and CBG showed neuroprotective effects against H2O2 or rotenone; however, both compounds were more effective in attenuating the rotenone-induced neurotoxicity. A high concentration of CBDA reduced the rotenone-induced neurotoxicity. WAY100635 (5-HT1A receptor antagonist) but not AM251 and AM630 (CB1 or CB2 receptor antagonists, respectively) significantly diminished the neuroprotective effect induced by CBG only against rotenone. Our results contribute to the understanding of the neuroprotective effect of CBD and CBG, showing differences with their acid forms, and also highlight the role of 5-HT1A receptors in the mechanisms of action of CBG.
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Cannabidiol/administración & dosificación , Cannabinoides/administración & dosificación , Peróxido de Hidrógeno/toxicidad , Fármacos Neuroprotectores/administración & dosificación , Receptor de Serotonina 5-HT1A/metabolismo , Rotenona/toxicidad , Animales , Cannabidiol/química , Cannabinoides/química , Cerebelo/efectos de los fármacos , Masculino , Neuronas/efectos de los fármacos , Ratas WistarRESUMEN
Metagenomic studies revealed the prevalence of Acidobacteria in soils, but the physiological and ecological reasons for their success are not well understood. Many Acidobacteria exhibit carotenoid-related pigments, which may be involved in their tolerance of environmental stress. The aim of this work was to investigate the role of the orange pigments produced by Acidobacteria strain AB23 isolated from a savannah-like soil and to identify putative carotenoid genes in Acidobacteria genomes. Phylogenetic analysis revealed that strain AB23 belongs to the Occallatibacter genus from the class Acidobacteriia (subdivision 1). Strain AB23 produced carotenoids in the presence of light and vitamins; however, the growth rate and biomass decreased when cells were exposed to light. The presence of carotenoids resulted in tolerance to hydrogen peroxide. Comparative genomics revealed that all members of Acidobacteriia with available genomes possess the complete gene cluster for phytoene production. Some Acidobacteriia members have an additional gene cluster that may be involved in the production of colored carotenoids. Both colored and colorless carotenoids are involved in tolerance to oxidative stress. These results show that the presence of carotenoid genes is widespread among Acidobacteriia. Light and atmospheric oxygen stimulate carotenoid synthesis, but there are other natural sources of oxidative stress in soils. Tolerance to environmental oxidative stress provided by carotenoids may offer a competitive advantage for Acidobacteria in soils.
Asunto(s)
Acidobacteria/genética , Acidobacteria/metabolismo , Farmacorresistencia Bacteriana/genética , Peróxido de Hidrógeno/toxicidad , Estrés Oxidativo/fisiología , Acidobacteria/efectos de los fármacos , Acidobacteria/aislamiento & purificación , Carotenoides/metabolismo , ADN Bacteriano/genética , Genoma Bacteriano/genética , Familia de Multigenes/genética , Suelo/química , Microbiología del SueloRESUMEN
Emodin (EM; 1,3,8-trihydroxy-6-methylanthracene-9,10-dione; C15H10O5) is an anthraquinone and exerts cytoprotective effects, as observed in both in vitro and in vivo experimental models. Mitochondrial dysfunction induced by reactive species plays a central role in the onset and progression of different human diseases. Thus, we have tested here whether a pretreatment (for 4 h) with EM (at 40 µM) would be able to promote mitochondrial protection in the human neuroblastoma SH-SY5Y cells exposed to the pro-oxidant agent hydrogen peroxide (H2O2). We found that the pretreatment with EM suppressed the effects of H2O2 on the activity of the mitochondrial complexes I and V, as well as on the production of adenosine triphosphate (ATP) and on the mitochondrial membrane potential (MMP). EM also prevented the H2O2-induced collapse in the tricarboxylic acid cycle (TCA) function. An anti-inflammatory role for EM was also observed in this experimental model, since this anthraquinone decreased the secretion of interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) by the H2O2-challenged cells. Inhibition of the adenosine monophosphate-activated protein kinase (AMPK) or silencing of the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) abolished the protection induced by EM in the H2O2-treated cells. Therefore, EM prevented the H2O2-induced mitochondrial dysfunction and pro-inflammatory state in the SH-SY5Y cells by an AMPK/Nrf2-dependent manner.
Asunto(s)
Antiinflamatorios/farmacología , Emodina/farmacología , Peróxido de Hidrógeno/toxicidad , Mitocondrias/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Antioxidantes/farmacología , Línea Celular Tumoral , Humanos , Factor 2 Relacionado con NF-E2/metabolismo , Oxidantes/toxicidad , Estrés Oxidativo/efectos de los fármacosRESUMEN
Chronic inflammation resulting from Helicobacter pylori (H. pylori) infection, the major risk factor for gastric cancer, results in increased release of reactive oxygen species (ROS), promoting oxidative stress and DNA damage. APE1 endonuclease, a key component of the base excision repair (BER) pathway, is responsible for the repair of damage induced by ROS. However, the APE1 gene and other DNA damage response (DDR) genes are still poorly understood in gastric cancer. Thus, we aimed to investigate whether the silencing of APE1 by shRNA can interfere with the survival of AGS gastric cancer cells after treatment with hydrogen peroxide (H2O2) and/or H. pylori extract (HPE) and its relation with the expression of DDR genes (ATM, ATR, and H2AX) and miRNAs that target DDR genes. In the AGS cells expressing APE1, isolated or combined treatment with H2O2 and HPE promoted a slight increase in the cell proliferation and increased the levels of intracellular ROS and DNA double strand breaks (DSBs) indicated by ©H2AX foci, a reduction in the proportion of cells in the G0/G1 phase and an increase in the initial apoptosis rate. Moreover, upregulation of APE1, ATR, miR-15a, miR-21, miR-24 and miR-421 and downregulation of ATM and H2AX was observed. In silenced AGS cells after treatment with H2O2 alone or combined with HPE, we observed an increase in the cell proliferation rate and the levels of intracellular ROS and DSBs and a reduction in the proportion of cells in S and G2/M phase arrest, leading to late apoptosis. APE1 knockdown also caused a reduction in the expression of ATM and miR-421, while ATR expression was increased. Based on our results, APE1 knockdown may promote changes in cellular processes by increasing genomic instability, leading to G2/M arrest and cell apoptosis, so it may be a promising strategy for controlling tumor progression.
Asunto(s)
Apoptosis , Reparación del ADN , ADN-(Sitio Apurínico o Apirimidínico) Liasa/genética , Puntos de Control de la Fase G2 del Ciclo Celular , Helicobacter pylori , Peróxido de Hidrógeno/toxicidad , Neoplasias Gástricas/fisiopatología , Proteínas de la Ataxia Telangiectasia Mutada/genética , Línea Celular Tumoral , Proliferación Celular , Roturas del ADN de Doble Cadena , Daño del ADN , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Histonas , Humanos , Peróxido de Hidrógeno/farmacología , MicroARNs/genética , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/terapiaRESUMEN
BACKGROUND Oxidative stress is responsible for generating DNA lesions and the 8-oxoguanine (8-oxoG) is the most commonly lesion found in DNA damage. When this base is incorporated during DNA replication, it could generate double-strand DNA breaks and cellular death. MutT enzyme hydrolyzes the 8-oxoG from the nucleotide pool, preventing its incorporation during DNA replication. OBJECTIVES To investigate the importance of 8-oxoG in Leishmania infantum and L. braziliensis, in this study we analysed the impact of heterologous expression of Escherichia coli MutT (EcMutT) enzyme in drug-resistance phenotype and defense against oxidative stress. METHODS Comparative analysis of L. braziliensis and L. infantum H2O2 tolerance and cell cycle profile were performed. Lines of L. braziliensis and L. infantum expressing EcMutT were generated and evaluated using susceptibility tests to H2O2 and SbIII, cell cycle analysis, γH2A western blotting, and BrdU native detection assay. FINDINGS Comparative analysis of tolerance to oxidative stress generated by H2O2 showed that L. infantum is more tolerant to exogenous H2O2 than L. braziliensis. In addition, cell cycle analysis showed that L. infantum, after treatment with H2O2, remains in G1 phase, returning to its normal growth rate after 72 h. In contrast, after treatment with H2O2, L. braziliensis parasites continue to move to the next stages of the cell cycle. Expression of the E. coli MutT gene in L. braziliensis and L. infantum does not interfere in parasite growth or in susceptibility to SbIII. Interestingly, we observed that L. braziliensis EcMutT-expressing clones were more tolerant to H2O2 treatment, presented lower activation of γH2A, a biomarker of genotoxic stress, and lower replication stress than its parental non-transfected parasites. In contrast, the EcMutT is not involved in protection against oxidative stress generated by H2O2 in L. infantum. MAIN CONCLUSIONS Our results showed that 8-oxoG clearance in L. braziliensis is important to avoid misincorporation during DNA replication after oxidative stress generated by H2O2.