Genomic Instability and Cytotoxicity Evaluation of Two Communities Exposed to Pesticides in the Mexicali Valley by the L-CBMN Assay.

The continuous biomonitoring of a population directly or indirectly exposed to pesticides could be an additional tool for decision makers to improve their health conditions. In this work, we performed biomonitoring on two groups of people from the Mexicali Valley who were continuously exposed to pesticides using the cytokinesis-block micronucleus cytome assay (L-CBMN) to evaluate cytotoxic and genotoxic damage in human peripheral blood lymphocytes. The study groups comprised 14 indigenous Cucapah with non-vegetarian habits (NV group) from Ejido el Mayor (32.12594°, -115.27265°) and 21 lacto-ovo vegetarian (LOV) persons from the Seventh-day Adventist Church of Ejido Vicente Guerrero (32.3961°, -115.14023°). The L-CBMN assay determines the nuclear division index (NDI), apoptosis, necrosis, micronuclei (MNs), nuclear buds (NBUDs), and nucleoplasmic bridges (NPBs). Our results show that, regardless of diet or daily habits, both the studied groups presented with cytogenotoxic damage compared with non-exposed pesticide individuals, without modifications to the nuclear division index. In the rest of the evaluated biomarkers, the NV group exhibited greater cytotoxic and genotoxic damage than the LOV group. Nevertheless, individuals practicing a lacto-ovo vegetarian diet (LOV) showed lower damage than those with non-vegetarian habits (NV), suggesting a better antioxidant response that helps decrease the genotoxic damage due to the enhanced intake of folates and antioxidants from a plant-based diet.

Lung Models to Evaluate Silver Nanoparticles' Toxicity and Their Impact on Human Health.

Nanomaterials (NMs) solve specific problems with remarkable results in several industrial and scientific areas. Among NMs, silver nanoparticles (AgNPs) have been extensively employed as drug carriers, medical diagnostics, energy harvesting devices, sensors, lubricants, and bioremediation. Notably, they have shown excellent antimicrobial, anticancer, and antiviral properties in the biomedical field. The literature analysis shows a selective cytotoxic effect on cancer cells compared to healthy cells, making its potential application in cancer treatment evident, increasing the need to study the potential risk of their use to environmental and human health. A large battery of toxicity models, both in vitro and in vivo, have been established to predict the harmful effects of incorporating AgNPs in these numerous areas or those produced due to involuntary exposure. However, these models often report contradictory results due to their lack of standardization, generating controversy and slowing the advances in nanotoxicology research, fundamentally by generalizing the biological response produced by the AgNP formulations. This review summarizes the last ten years' reports concerning AgNPs' toxicity in cellular respiratory system models (e.g., mono-culture models, co-cultures, 3D cultures, ex vivo and in vivo). In turn, more complex cellular models represent in a better way the physical and chemical barriers of the body; however, results should be used carefully so as not to be misleading. The main objective of this work is to highlight current models with the highest physiological relevance, identifying the opportunity areas of lung nanotoxicology and contributing to the establishment and strengthening of specific regulations regarding health and the environment.

Bell Shape Curves of Hemolysis Induced by Silver Nanoparticles: Review and Experimental Assay.

The hemolytic activity assay is a versatile tool for fast primary toxicity studies. This work presents a systematic study of the hemolytic properties of ArgovitTM silver nanoparticles (AgNPs) extensively studied for biomedical applications. The results revealed an unusual and unexpected bell-shaped hemolysis curve for human healthy and diabetic donor erythrocytes. With the decrease of pH from 7.4 and 6.8 to 5.6, the hemolysis profiles for AgNPs and AgNO3 changed dramatically. For AgNPs, the bell shape changed to a step shape with a subsequent sharp increase, and for AgNO3 it changed to a gradual increase. Explanations of these changes based on the aggregation of AgNPs due to the increase of proton concentration were suggested. Hemolysis of diabetic donor erythrocytes was slightly higher than that of healthy donor erythrocytes. The meta-analysis revealed that for only one AgNPs formulation (out of 48), a bell-shaped hemolysis profile was reported, but not discussed. This scarcity of data was explained by the dominant goal of studies consisting in achieving clinically significant hemolysis of 5-10%. Considering that hemolysis profiles may be bell-shaped, it is recommended to avoid extrapolations and to perform measurements in a wide concentration interval in hemolysis assays.

AgNPs Argovit™ Modulates Cyclophosphamide-Induced Genotoxicity on Peripheral Blood Erythrocytes In Vivo.

Silver nanoparticles (AgNPs) have been studied worldwide for their potential biomedical applications. Specifically, they are proposed as a novel alternative for cancer treatment. However, the determination of their cytotoxic and genotoxic effects continues to limit their application. The commercially available silver nanoparticle Argovit™ has shown antineoplastic, antiviral, antibacterial, and tissue regenerative properties, activities triggered by its capacity to promote the overproduction of reactive oxygen species (ROS). Therefore, in this work, we evaluated the genotoxic and cytotoxic potential of the Argovit™ formulation (average size: 35 nm) on BALB/c mice using the micronucleus in a peripheral blood erythrocytes model. Besides, we evaluated the capability of AgNPs to modulate the genotoxic effect induced by cyclophosphamide (CP) after the administration of the oncologic agent. To achieve this, 5-6-week-old male mice with a mean weight of 20.11 ± 2.38 g were treated with water as negative control (Group 1), an single intraperitoneal dose of CP (50 mg/kg of body weight, Group 2), a daily oral dose of AgNPs (6 mg/kg of weight, Group 3) for three consecutive days, or a combination of these treatment schemes: one day of CP doses (50 mg/kg of body weight) followed by three doses of AgNPs (one dose per day, Group 4) and three alternate doses of CP and AgNPs (six days of exposure, Group 5). Blood samples were taken just before the first administration (0 h) and every 24 h for seven days. Our results show that Argovit™ AgNPs induced no significant cytotoxic or acute genotoxic damage. The observed cumulative genotoxic damage in this model could be caused by the accumulation of AgNPs due to administered consecutive doses. Furthermore, the administration of AgNPs after 24 h of CP seems to have a protective effect on bone marrow and reduces by up to 50% the acute genotoxic damage induced by CP. However, this protection is not enough to counteract several doses of CP. To our knowledge, this is the first time that the exceptional chemoprotective capacity produced by a non-cytotoxic silver nanoparticle formulation against CP genotoxic damage has been reported. These findings raise the possibility of using AgNPs as an adjuvant agent with current treatments, reducing adverse effects.

Hemolysis of Human Erythrocytes by Argovit™ AgNPs from Healthy and Diabetic Donors: An In Vitro Study.

The use of nanomaterials is becoming increasingly widespread, leading to substantial research focused on nanomedicine. Nevertheless, the lack of complete toxicity profiles limits nanomaterials' uses, despite their remarkable diagnostic and therapeutic results on in vitro and in vivo models. Silver nanoparticles (AgNPs), particularly Argovit™, have shown microbicidal, virucidal, and antitumoral effects. Among the first-line toxicity tests is the hemolysis assay. Here, the hemolytic effect of Argovit™ AgNPs on erythrocytes from one healthy donor (HDE) and one diabetic donor (DDE) is evaluated by the hemolysis assay against AgNO3. The results showed that Argovit™, in concentrations ≤24 µg/mL of metallic silver, did not show a hemolytic effect on the HDE or DDE. On the contrary, AgNO3 at the same concentration of silver ions produces more than 10% hemolysis in both the erythrocyte types. In all the experimental conditions assessed, the DDE was shown to be more prone to hemolysis than the HDE elicited by Ag+ ions or AgNPs, but much more evident with Ag+ ions. The results show that Argovit™ is the least hemolytic compared with the other twenty-two AgNP formulations previously reported, probably due to the polymer mass used to stabilize the Argovit™ formulation. The results obtained provide relevant information that contributes to obtaining a comprehensive toxicological profile to design safe and effective AgNP formulations.

New Protein-Coated Silver Nanoparticles: Characterization, Antitumor and Amoebicidal Activity, Antiproliferative Selectivity, Genotoxicity, and Biocompatibility Evaluation.

Nanomaterials quickly evolve to produce safe and effective biomedical alternatives, mainly silver nanoparticles (AgNPs). The AgNPs' antibacterial, antiviral, and antitumor properties convert them into a recurrent scaffold to produce new treatment options. This work reported the full characterization of a highly biocompatible protein-coated AgNPs formulation and their selective antitumor and amoebicidal activity. The protein-coated AgNPs formulation exhibits a half-inhibitory concentration (IC50) = 19.7 µM (2.3 µg/mL) that is almost 10 times more potent than carboplatin (first-line chemotherapeutic agent) to inhibit the proliferation of the highly aggressive human adenocarcinoma HCT-15. The main death pathway elicited by AgNPs on HCT-15 is apoptosis, which is probably stimulated by reactive oxygen species (ROS) overproduction on mitochondria. A concentration of 111 µM (600 µg/mL) of metallic silver contained in AgNPs produces neither cytotoxic nor genotoxic damage on human peripheral blood lymphocytes. Thus, the AgNPs formulation evaluated in this work improves both the antiproliferative potency on HCT-15 cultures and cytotoxic selectivity ten times more than carboplatin. A similar mechanism is suggested for the antiproliferative activity observed on HM1-IMSS trophozoites (IC50 = 69.2 µM; 7.4 µg/mL). There is no change in cell viability on mice primary cultures of brain, liver, spleen, and kidney exposed to an AgNPs concentration range from 5.5 µM to 5.5 mM (0.6 to 600 µg/mL). The lethal dose was determined following the OECD guideline 420 for Acute Oral Toxicity Assay, obtaining an LD50 = 2618 mg of Ag/Kg body weight. All mice survived the observational period; the histopathology and biochemical analysis show no differences compared with the negative control group. In summary, all results from toxicological evaluation suggest a Category 5 (practically nontoxic) of the Globally Harmonized System of Classification and Labelling of Chemicals for that protein-coated AgNPs after oral administration for a short period and urge the completion of its preclinical toxicological profile. These findings open new opportunities in the development of selective, safe, and effective AgNPs formulations for the treatment of cancer and parasitic diseases with a significant reduction of side effects.

Argovit™ Silver Nanoparticles Effects on Allium cepa: Plant Growth Promotion without Cyto Genotoxic Damage.

Due to their antibacterial and antiviral effects, silver nanoparticles (AgNP) are one of the most widely used nanomaterials worldwide in various industries, e.g., in textiles, cosmetics and biomedical-related products. Unfortunately, the lack of complete physicochemical characterization and the variety of models used to evaluate its cytotoxic/genotoxic effect make comparison and decision-making regarding their safe use difficult. In this work, we present a systematic study of the cytotoxic and genotoxic activity of the commercially available AgNPs formulation Argovit™ in Allium cepa. The evaluated concentration range, 5-100 µg/mL of metallic silver content (85-1666 µg/mL of complete formulation), is 10-17 times higher than the used for other previously reported polyvinylpyrrolidone (PVP)-AgNP formulations and showed no cytotoxic or genotoxic damage in Allium cepa. Conversely, low concentrations (5 and 10 µg/mL) promote growth without damage to roots or bulbs. Until this work, all the formulations of PVP-AgNP evaluated in Allium cepa regardless of their size, concentration, or the exposure time had shown phytotoxicity. The biological response observed in Allium cepa exposed to Argovit™ is caused by nanoparticles and not by silver ions. The metal/coating agent ratio plays a fundamental role in this response and must be considered within the key physicochemical parameters for the design and manufacture of safer nanomaterials.

Genetic Instability of a Polydactyl Hypopigmented Cat With Squamous Cell Carcinoma-A Case Report.

Polydactyly, hypopigmentation, and squamous cell carcinoma are common in cats. However, a cat exhibiting all of these conditions has not yet been reported. This study presents the case of a 14- year-old male Mexican cat, hypopigmented, with supernumerary fingers, two preaxial and one on each posterior limb, admitted to the clinic with a lesion in the left periocular region. The cat was subjected to a general physical examination, blood, and urine chemistry, as well as a biopsy and genomic instability assessment with an analysis of the red blood cells (RBC) micronucleated erythrocytes (RBC-MNE) in the peripheral blood. The biopsy was positive for squamous cell carcinoma, and the RBC-MNE count (8.6 MNE/1000 erythrocytes) was high compared to that previously described in other domestic cats or wild cats. Thus, the genomic instability of the RBC-MNE could be used as an indicator to identify clinical conditions of felines, particularly those with one of the characteristics exhibited by this Mexican cat. The RBC-MNE test is the most widely used in the world for the evaluation of DNA damage, but to our knowledge, it has not been used to identify vulnerable non-human specimens.

Cytokinesis-Block Micronucleus Assay Using Human Lymphocytes as a Sensitive Tool for Cytotoxicity/Genotoxicity Evaluation of AgNPs.

Silver nanoparticles (AgNPs) are the most used nanomaterials worldwide due to their excellent antibacterial, antiviral, and antitumor activities, among others. However, there is scarce information regarding their genotoxic potential measured using human peripheral blood lymphocytes. In this work, we present the cytotoxic and genotoxic behavior of two commercially available poly(vinylpyrrolidone)-coated silver nanoparticle (PVP-AgNPs) formulations that can be identified as noncytotoxic and nongenotoxic by just evaluating micronuclei (MNi) induction and the mitotic index, but present enormous differences when other parameters such as cytostasis, apoptosis, necrosis, and nuclear damage (nuclear buds (NBUDs) and nucleoplasmic bridges (NPBs)) are analyzed. The results show that Argovit (35 nm PVP-AgNPs) and nanoComposix (50 nm PVP-AgNPs), at concentrations from 0.012 to 12 µg/mL, produce no changes in the nuclear division index (NDI) or micronuclei (MNi) frequency compared with the values found on control cultures of human blood peripheral lymphocytes from a healthy donor. Still, 50 nm PVP-AgNPs significantly decrease the replication index and significantly increase cytostasis, apoptosis, necrosis, and the frequencies of nuclear buds (NBUDs) and nucleoplasmic bridges (NPBs). These results provide evidence that the cytokinesis-block micronucleus (CBMN) assay using human lymphocytes and evaluating the eight parameters provided by the technique is a sensitive, fast, accurate, and inexpensive detection tool to support or discard AgNPs or other nanomaterials, which is worthwhile for continued testing of their effectiveness and toxicity for biomedical applications. In addition, it provides very important information about the role played by the [coating agent]/[metal] ratio in the design of nanomaterials that could reduce adverse effects as much as possible while retaining their therapeutic capabilities.

Cytotoxic, Genotoxic, and Polymorphism Effects on Vanilla planifolia Jacks ex Andrews after Long-Term Exposure to Argovit® Silver Nanoparticles.

Worldwide demands of Vanilla planifolia lead to finding new options to produce large-scale and contaminant-free crops. Particularly, the Mexican Government has classified Vanilla planifolia at risk and it subject to protection programs since wild species are in danger of extinction and no more than 30 clones have been found. Nanotechnology could help to solve both demands and genetic variability, but toxicological concerns must be solved. In this work, we present the first study of the cytotoxic and genotoxic effects promoted by AgNPs in Vanilla planifolia plantlets after a very long exposure time of six weeks. Our results show that Vanilla planifolia plantlets growth with doses of 25 and 50 mg/L is favored with a small decrease in the mitotic index. A dose-dependency in the frequency of cells with chromosomal aberrations and micronuclei was found. However, genotoxic effects could be considered as minimum due to with the highest concentration employed (200 mg/L), the total percentage of chromatic aberrations is lower than 5% with only three micronuclei in 3000 cells, despite the long-time exposure to AgNP. Therefore, 25 and 50 mg/L (1.5 and 3 mg/L of metallic silver) were identified as safe concentrations for Vanilla planifolia growth on in vitro conditions. Exposure of plantlets to AgNPs increase the polymorphism registered by inter-simple sequence repeat method (ISSR), which could be useful to promote the genetic variability of this species.

Aglomeración urbana en la estimación de escenarios de riesgo sanitario por emisiones de gasolineras: el caso de Ensenada, Baja California / Urban crowding in the estimation of health risk scenarios caused by emissions from gas stations: the case of Ensenada, Baja California / Aglomeração urbana na estimação de cenários de risco para a saúde por emissões em postos de gasolina: o caso da cidade de Ensenada, Baixa Califórnia

Resumen Objetivo: se propone una herramienta conceptual y metodológica mediante la cual es posible representar la contribución de los componentes sociales, económicos y territoriales en la aglomeración de personas dentro de una ciudad, para delimitar zonas de riesgo sanitario por la exposición a emisiones de gasolina en estaciones de servicio. Resultados: el modelo propuesto facilita la focalización, identificación y priorización las zonas de riesgo por contaminación ambiental por BTEX liberados por gasolineras. Discusión: la inclusión en modelos espaciales de riesgo, del número de personas que acuden a construcciones como escuelas y hospitales que generan aglomeración, trasciende el ámbito conceptual y ofrece aspectos metodológicos e instrumentales para lograr modelos más robustos y aplicables en otras ciudades. Las agencias gubernamentales deben considerar estos resultados para el establecimiento de reglas, permisos y procedimientos de ejecución con el fin de reducir la contaminación del medio ambiente y, con esto, mejorar las condiciones sanitarias en el entorno complejo de una zona urbana. Conclusiones: el análisis espacial integrado no resuelve las complicadas negociaciones políticas y sociales que se tienen que hacer en la toma de decisiones sobre los riesgo sanitario, lo que sí mejora es la capacidad de los científicos y tomadores de decisiones en la identificación, evaluación, control y reducción de estos riesgos asociados con las emisiones de las estaciones de servicio.

Abstract Objective: a conceptual and methodological tool is proposed which makes it possible to represent how social, economic and territorial components contribute to the crowding of people within a city. This tool aims to define the areas with health risk due to exposure to gasoline emissions from gas stations. Results: the proposed model can facilitate the targeting, identification and prioritization of zones at risk of environmental contamination by the BTEX released from gas stations in the city. Discussion: when a spatial model of risk includes the number of people going to buildings that generate crowding such as schools and hospitals, the conceptual scope is transcended and methodological and instrumental aspects are offered in order to achieve more robust models that are applicable to other cities. Government agencies should take these results into account when establishing rules, permits and enforcement procedures to reduce environmental contamination. This would thus improve the health conditions in the complex environment of an urban area. Conclusions: integrated spatial analysis does not solve the complicated social and political negotiations that must take place in any decision making concerning health risk. However, it does improve the ability of scientists and decision-makers to identify, assess, control and reduce the risks associated with emissions from gas stations.

Resumo Objetivo: Propõe-se uma ferramenta conceitual e metodológica por meio da qual é possível representar a contribuição dos componentes sociais, econômicos e territoriais na aglomeração de pessoas em uma cidade, para demarcar zonas de risco para a saúde por causa da exposição a emissões de gasolina em postos de abastecimento. Resultados: O modelo proposto facilita a focalização, identificação e priorização das zonas de risco por poluição ambiental por BTEX emitidos pelos postos de gasolina. Discussão: A inclusão em modelos espaciais de risco, do número de pessoas que frequentam estabelecimentos como escolas e hospitais que geram aglomeração, transcende o âmbito conceitual e oferece aspectos metodológicos e instrumentais para conseguir modelos mais robustos e aplicáveis em outras cidades. As agências governamentais precisam considerar estes resultados para a criação de regras, autorizações e procedimentos de execução com o propósito de reduzir a poluição do meio-ambiente e, assim, melhorar as condições de saúde no entorno complexo de uma zona urbana. Conclusões: A análise espacial integrada não resolve as complicadas negociações políticas e sociais que devem acontecer na tomada de decisões sobre os riscos de saúde, mas o que melhora é a capacidade dos cientistas tomadores de decisões na identificação, avaliação, controle e redução destes riscos associados com as emissões dos postos de abastecimento.

Biomonitoring with Micronuclei Test in Buccal Cells of Female Farmers and Children Exposed to Pesticides of Maneadero Agricultural Valley, Baja California, Mexico.

Feminization of the agricultural labor is common in Mexico; these women and their families are vulnerable to several health risks including genotoxicity. Previous papers have presented contradictory information with respect to indirect exposure to pesticides and DNA damage. We aimed to evaluate the genotoxic effect in buccal mucosa from female farmers and children, working in the agricultural valley of Maneadero, Baja California. Frequencies of micronucleated cells (MNc) and nuclear abnormalities (NA) in 2000 cells were obtained from the buccal mucosa of the study population (n = 144), divided in four groups: (1) farmers (n = 37), (2) unexposed (n = 35), (3) farmers' children (n = 34), and (4) unexposed children (n = 38). We compared frequencies of MNc and NA and fitted generalized linear models to investigate the interaction between these variables and exposition to pesticides. Differences were found between farmers and unexposed women in MNc (p < 0.0001), CC (p = 0.3376), and PN (p < 0.0001). With respect to exposed children, we found higher significant frequencies in MNc (p < 0.0001), LN (p < 0.0001), CC (p < 0.0001), and PN (p < 0.004) when compared to unexposed children. Therefore working as a farmer is a risk for genotoxic damage; more importantly indirectly exposed children were found to have genotoxic damage, which is of concern, since it could aid in future disturbances of their health.

Factores que inciden el daño oxidativo en niños con obesidad: estudio piloto / Factors affecting oxidative damage in obese children: an exploratory study

Introducción: La obesidad es un trastorno metabólico que crea condiciones oxidantes, las cuales pueden generar niveles elevados de estrés fisiológico, así como una perturbación en el estado de oxidación-reducción celular conocido como Estrés Oxidativo. Objetivo: Examinar la asociación entre el daño en el ADN cromosómico y la capacidad antioxidante total (TAC) en niños clasificados con obesidad severa. Métodos: En el estudio participaron 11 niños con edad e índice de masa corporal promedio de 9.5±1.2 años y 27.7±3.3 kg/m2 , respectivamente, de quienes se obtuvieron muestras de sangre entera venosa y se analizó algunos factores de riesgo característicos del síndrome metabólico, así como el número de sitios abásicos (SA) en la molécula de ADN y los niveles de CAT. Los biomarcadores se determinaron utilizando técnicas espectrofotométricas y de ensayo ELISA. Resultados: Se reconocieron en promedio 4.0±4.1x105 sitios abásicos en la molécula de ADN y un nivel de concentración en plasma sanguíneo de la Capacidad Antioxidante Total de 0.218±0.03 mmol/L, donde se obtuvo una correlación inversa entre ambas variables (r = - 0.63, p = 0.038, r2 = 0.4). Advirtiéndose un desequilibrio del estado de reducción-oxidación (REDOX) celular. Conclusión: Los valores altos de sitios abásicos y bajos niveles de concentración de la Capacidad Antioxidante Total en presencia de obesidad severa sugieren la existencia de estrés oxidativo, lo que podría considerarse como un factor de riesgo alto, vinculado al desarrollo temprano de comorbilidades asociadas a la obesidad (AU)

Introduction: Obesity is a metabolic disorder that creates oxidizing conditions, which can generate high levels of physiological stress as well as a disturbance in the state of redox cell known as Oxidative Stress. Objective: To examine the association between the damage on chromosomal DNA and the total antioxidant capacity (TAC) in obese children with severe obesity. Methods: Participants were 11 children with a mean age and body mass index of 9.5±1.2 years and 27.7±3.3 kg/m2, respectively, from which venous blood samples were obtained to determine distinctive risk factors of metabolic syndrome, the number of DNA abasic sites (AS) and TAC levels. Biomarkers were quantified from spectrophotometric techniques and ELISA assays. Results: Were identified 4.1±4.0x105 AS and TAC of 0.218±0.03 mmol/L, and an inverse correlation between AS and TAC (r = -0.63, p=0.038). These results suggest an imbalance in reduction-oxidation status (REDOX) within the cell. Conclusion: Increased AS and decreased TAC concentrations in the presence of severe obesity suggest that oxidative stress could be considered as an important risk factor closely linked to the early development of comorbidities associated to obesity (AU)

[Factors affecting oxidative damage in obese children: an exploratory study]. / Factores que inciden el daño oxidativo en niños con obesidad: estudio piloto.

INTRODUCTION: Obesity is a metabolic disorder that creates oxidizing conditions, which can generate high levels of physiological stress as well as a disturbance in the state of redox cell known as Oxidative Stress. OBJECTIVE: To examine the association between the damage on chromosomal DNA and the total antioxidant capacity (TAC) in obese children with severe obesity. METHODS: Participants were 11 children with a mean age and body mass index of 9.5±1.2 years and 27.7±3.3 kg/m2, respectively, from which venous blood samples were obtained to determine distinctive risk factors of metabolic syndrome, the number of DNA abasic sites (AS) and TAC levels. Biomarkers were quantified from spectrophotometric techniques and ELISA assays. RESULTS: Were identified 4.1±4.0x105 AS and TAC of 0.218±0.03 mmol/L, and an inverse correlation between AS and TAC (r = -0.63, p=0.038). These results suggest an imbalance in reduction-oxidation status (REDOX) within the cell. CONCLUSION: Increased AS and decreased TAC concentrations in the presence of severe obesity suggest that oxidative stress could be considered as an important risk factor closely linked to the early development of comorbidities associated to obesity.

Introducción: La obesidad es un trastorno metabólico que crea condiciones oxidantes, las cuales pueden generar niveles elevados de estrés fisiológico, así como una perturbación en el estado de oxidación-reducción celular conocido como Estrés Oxidativo. Objetivo: Examinar la asociación entre el daño en el ADN cromosómico y la capacidad antioxidante total (TAC) en niños clasificados con obesidad severa. Métodos: En el estudio participaron 11 niños con edad e índice de masa corporal promedio de 9.5±1.2 años y 27.7±3.3 kg/m2, respectivamente, de quienes se obtuvieron muestras de sangre entera venosa y se analizó algunos factores de riesgo característicos del síndrome metabólico, así como el número de sitios abásicos (SA) en la molécula de ADN y los niveles de CAT. Los biomarcadores se determinaron utilizando técnicas espectrofotométricas y de ensayo ELISA. Resultados: Se reconocieron en promedio 4.0±4.1x105 sitios abásicos en la molécula de ADN y un nivel de concentración en plasma sanguíneo de la Capacidad Antioxidante Total de 0.218±0.03 mmol/L, donde se obtuvo una correlación inversa entre ambas variables (r = - 0.63, p = 0.038, r2 = 0.4). Advirtiéndose un desequilibrio del estado de reducción-oxidación (REDOX) celular. Conclusión: Los valores altos de sitios abásicos y bajos niveles de concentración de la Capacidad Antioxidante Total en presencia de obesidad severa sugieren la existencia de estrés oxidativo, lo que podría considerarse como un factor de riesgo alto, vinculado al desarrollo temprano de comorbilidades asociadas a la obesidad.