SUMMARY: Magnolia bark extract supplementation has an anti-oxidative role in mammalians. However, its role in physiological aged-associated heart insufficiency is not known yet. Therefore, we investigated the effects of a magnolia bark complex, including magnolol and honokiol components (MAHOC), in elderly rat hearts (24-month-old aged group). One group of aged rats was supplemented with MAHOC (400 mg/kg/d, for 12 weeks) besides the standard rat diet while the second group of elderly rats and adult rats (to 6-month- old adult-group) were only fed with the standard rat diet. The morphological analysis using light microscopy has shown marked myofibrillar losses, densely localized fibroblasts, vacuolizations, infiltrated cell accumulations, and collagen fibers in the myocardium of the elderly rats compared to the adults. We also detected a markedly increased amount of degenerated cardiomyocytes including the euchromatic nucleus. The MAHOC supplementation of the elderly rats provided marked ameliorations in these abnormal morphological changes in the heart tissue. Furthermore, electrophysiological analysis of electrocardiograms (ECGs) in the supplemented group showed significant attenuations in the prolonged durations of P-waves, QRS-complexes, QT-intervals, and low heart rates compared to the unsupplemented elderly group. The biochemical analysis also showed significant attenuations in the activity of arylesterase and total antioxidant status in the myocardium of the supplemented group. We further determined significant attenuations in the activity of a mitochondrial enzyme succinate dehydrogenase, known as a source of reactive oxygen species (ROS), and the decreased level of ATP/ADP in the heart homogenates of the supplemented group. Moreover, under in vitro conditions by using an aging-mimicked cardiac cell line induced by D-galactose, we demonstrated that MAHOC treatment could provide prevention of depolarization in mitochondria membrane potential and high-level ROS production. Overall, our data presented significant myocardial ameliorations in physiological aging-associated morphological alterations parallel to the function and biochemical attenuations with MAHOC supplementation, at most, through recoveries in mitochondria.

RESUMEN: La suplementación con extracto de corteza de magnolia tiene un papel antioxidante en los mamíferos, sin embargo, su rol en la insuficiencia cardíaca asociada al envejecimiento fisiológico aún no se conoce. Por lo anterior, investigamos los efectos de un complejo de corteza de magnolia, incluidos los componentes magnolol y honokiol (MAHOC), en corazones de ratas seniles (grupo de edad de 24 meses). La alimentación de grupo de ratas seniles se complementó con MAHOC (400 mg/kg/d, durante 12 semanas) además de la dieta estándar, mientras que el segundo grupo de ratas seniles y ratas adultas (hasta el grupo de adultos de 6 meses) solo recibió la dieta estándar para ratas. El análisis morfológico mediante microscopía óptica ha mostrado marcadas pérdidas miofibrilares, fibroblastos densamente localizados, vacuolizaciones, acumulaciones de células infiltradas y fibras de colágeno en el miocardio de las ratas seniles en comparación con las adultas. También detectamos una cantidad notablemente mayor de cardiomiocitos degradados, incluido el núcleo eucromático. La suplementación con MAHOC de las ratas seniles proporcionó mejoras marcadas en estos cambios morfológicos anormales en el tejido cardiaco. Por otra parte, el análisis de los electrocardiogramas (ECG) en el grupo suplementado mostró atenuaciones significativas en las duraciones prolongadas de las ondas P, los complejos QRS, los intervalos QT y las frecuencias cardíacas bajas, en comparación con el grupo de ratas seniles sin suplementación alimenticia. El análisis bioquímico también mostró atenuaciones significativas en la actividad de la arilesterasa y el estado antioxidante total en el miocardio del grupo suplementado. Determinamos además atenuaciones significativas en la actividad de la enzima mitocondrial succinato deshidrogenasa, conocida como fuente de especies reactivas de oxígeno (ROS), y la disminución del nivel de ATP/ADP en los homogeneizados de corazón del grupo suplementado. Además, en condiciones in vitro mediante el uso de una línea de células cardíacas, imitando el envejecimiento inducido por D- galactosa, demostramos que el tratamiento con MAHOC podría prevenir la despolarización en el potencial de membrana de las mitocondrias y la producción de ROS de alto nivel. En general, nuestros datos presentaron mejoras miocárdicas significativas en alteraciones morfológicas asociadas con el envejecimiento fisiológico paralelas a la función y atenuaciones bioquímicas con la suplementación con MAHOC, como máximo, a través de recuperaciones en las mitocondrias.

Abstract Background Various studies are ongoing related to the radioprotective agents. Herbal preparations are currently becoming popular because of their beneficial effects with fewer side effects compared to the synthetic/semi-synthetic medicines, and Nigella sativa oil (NSO) is only one of them. Objective To investigate NSO for its antioxidant effects on the heart tissue of rats exposed to ionizing radiation (IR). Methods Thirty six male albino Wistar rats, divided into four groups, were designated to group I (IR plus NSO group) that received both 5 Gray of gamma IR to total cranium and NSO; group II (IR alone group) that received IR plus saline, group III (control group of NSO) that received saline and did not receive NSO or IR; group IV (control group) that received only sham IR. Alterations in Total antioxidant status (TAS) and Total oxidant status (TOS), Oxidative stres index (OSI), Sulhydryl group (SH), Lipid hydroperoxide (LOOH), Paraoxonase (PON) levels, Arylesterase (ARE) and Ceruloplasmin (CER) activities in homogenized heart tissue of rats were measured by biochemical methods. Results In heart tissue of the rats in the IR alone group (group II) LOOH, TOS and OSI levels were found to be higher, ARE activity and TAS level were found to be lower than all of the other groups (p < 0.01). These results also support that IR increases oxidative stress and NSO's protective effect. Conclusion NSO would reduce the oxidative damage in the irradiated heart tissue in the experimental rat model.

Resumo Objetivo: A enzima cardioprotetora Paraoxonase 1 (PON1) sofre importante influência de polimorfismos genéticos e fatores nutricionais. O objetivo deste estudo foi investigar a influência da alimentação, do estado nutricional e do polimorfismo C(-107)T sobre a atividade arilesterase da PON1 em crianças. Métodos: Estudo transversal com 97 crianças entre 5 e 8 anos, de ambos os sexos, de um ambulatório de pediatria no sul do Brasil. Realizou-se questionário sociodemográfico, de comportamento e de consumo alimentar, medidas antropométricas e coleta de sangue em laboratório. A atividade arilesterase da PON1 foi mensurada pela extinção de fenol (U/mL), realizada extração do DNA e análise do polimorfismo PON1 C(-107)T. O equilíbrio de Hardy-Weinberg foi testado com qui-quadrado e usada regressão linear para estimar a atividade da PON1 segundo quatro modelos de ajuste, erro aceitável de 5%. Resultados: Na amostra o sexo masculino representou 50,5%, 39,2% tinham 6 anos, 54,5% eram eutróficos e 51,5% tinha atividade da PON1 inferior à mediana (90,0;15-30 U/ml). A frequência dos genótipos foi 54,6% (53/97), 31,0% (30/97) e 14,4% (14/97), respectivamente, para CT, CC e TT, estiveram em equilíbrio de Hardy-Weinberg (p = 0,22). Na análise de regressão o modelo que incluiu variáveis sociodemográficas, de frequência do consumo de frutas, verduras, legumes, laticínios e feijões estimou uma variabilidade de 14,8% na atividade da PON1 combinada ao polimorfismo PON1 C(-107)T. Conclusões: Na infância uma alimentação de boa qualidade, com maior participação de alimentos saudáveis foi importante para predizer a atividade da enzima cardioprotetora PON1 combinada ao polimorfismo C(-107)T do gene da PON1.

Abstract Objective: The cardioprotective enzyme paraoxonase-1 (PON1) suffers an important influence from genetic polymorphisms and nutritional factors. The aim of this study was to investigate the influence of diet, nutritional status, and the C(-107)T polymorphism on PON1 arylesterase activity in children. Methods: This was a cross-sectional study with 97 children, aged between 5 and 8 years, of both genders, from a pediatric outpatient clinic in southern Brazil. A sociodemographic, behavioral, and food consumption questionnaire was applied, and anthropometric measurements and laboratory blood samples were taken. PON1 arylesterase activity was measured by phenol extinction (U/mL), and DNA extraction and analysis of the PON1 C(-107)T polymorphism were performed. The Hardy-Weinberg equilibrium was tested with the chi-squared test and linear regression was used to estimate PON1 activity according to four adjustment models, with an acceptable error of 5%. Results: In the sample, the male gender accounted for 50.5%, 39.2% were 6 years of age, 54.5% had normal weight, and 51.5% had PON1 activity below the median (90.0, 15-30 U/mL). Genotype frequency was 54.6% (53/97), 31.0% (30/97), and 14.4% (14/97), respectively, for CT, CC, and TT, consistent with the Hardy-Weinberg equilibrium (p = 0.22). In the regression analysis, the model that included sociodemographic variables as well as frequency of consumption of fruits, vegetables, legumes, dairy products, and beans estimated a variability of 14.8% in PON1 activity combined with the PON1 C(-107)T polymorphism. Conclusions: During childhood, a good-quality diet with greater inclusion of healthy foods was important to predict the activity of the cardioprotective enzyme PON1 combined with the C(-107)T polymorphism of the PON1 gene.

ABSTRACT Objective Our objective in this study was to evaluate the factors predicting female sexual dysfunction (FSD) in patients with diabetes mellitus (DM). Subjects and methods The study included 149 women with DM. Sexual function was evaluated with the Female Sexual Function Index (FSFI) questionnaire, in which total scores under 26.55 characterized the occurrence of FSD (Group 1 > 26.55, Group 2 < 26.55). We recorded the patients’ demographic, metabolic, and hormonal data. Ophthalmologic, neurologic, and renal complications were also evaluated. The antioxidant status of the patients in both groups was determined by measuring the activity of the enzymes paraoxonase-1 (PON-1) and arylesterase (ARE). Results Based on the FSFI scores, 60 patients were allocated to Group 1 (26.6 ± 12.3) and 89 to Group 2 (22.6 ± 9.5). Group 2 compared with Group 1 had significantly (p < 0.05) higher mean concentrations of glycated hemoglobin (HbA1c), glucose, triglycerides, and insulin, along with higher rates of metformin use, smoking, retinopathy, and nephropathy. The mean serum ARE concentrations were significantly lower in Group 2 compared with Group 1 (p = 0.000), but the mean serum PON-1 concentrations were similar between both groups (p = 0.218). On multivariable regression analysis, age, ARE activity, Beck Depression Inventory (BDI) score, and menopause were significant independent predictors of FSD (p < 0.05). Conclusions In this study, we evaluated the predictive factors determining FSD caused by DM. Despite the significant results found in our study, future randomized controlled studies with a long follow-up and a larger number of patients are required to determine how DM affects FSD.

RESUMO OBJETIVO: Examinamos o efeito da administração intracameral da cefuroxima sobre o estresse oxidativo e a apoptose endotelial no tecido corneano de ratos. MÉTODOS: No total, 30 ratos foram divididos em 3 grupos de 10 ratos cada (administração intracameral de cefuroxima 0,1 mg/0,01 mL (grupo cefuroxima), administração intracameral de solução salina balanceada 0,01 mL (grupo controle) ou ausência de injeção intracameral (grupo sham)). A apoptose endotelial da córnea foi avaliada por análise imuno-histoquimica usando caspase-3 e -8. O status oxidante total, o status antioxidante total, o índice de estresse oxidativo e os níveis de a paraoxonase e arilesterase foram investigados no tecido endotelial da córnea e no soro. RESULTADOS: Os níveis de paraoxonase no soro foram significativamente diferentes entre os grupos sham e cefuroxima (p=0,027). Foi também observada uma diferença significativa nos níveis de estado oxidante total entre os grupos cefuroxima e solução salina balanceada (p=0,023). Além disso, houve diferenças significativas nos níveis de status antioxidante total no tecido da córnea entre os grupos cefuroxima e sham (p<0,001) e entre os grupos cefuroxima e solução salina balanceada (p<0,001). Diferenças significativas também foram observadas nos níveis do índice de estresse oxidativo entre os grupos cefuroxima e solução salina balanceada (p=0,001) e entre os grupos cefuroxima e sham (p=0,026). De acordo com os resultados de coloração imuno-histoquimica, houve associação significativa com a atividade da caspase-3 entre os grupos cefuroxima e solução salina balanceada (p=0,007), enquanto não houve diferença significativa com a atividade da caspase-8 (p=0,541). A atividade da caspase-3 exibiu uma relação significativa entre os grupos sham e solução salina balanceada (p=0,018), mas nenhuma relação foi encontrada com a atividade da caspase-8 (p=0,623). CONCLUSÃO: O exame imuno-histoquímico revelou que a cefuroxima intracameral aumentou a apoptose quando comparada com os grupos sham e solução salina balanceada. Além disso, a cefuroxima intracameral aumentou o estresse oxidativo na córnea e induziu simultaneamente a apoptose.

ABSTRACT PURPOSE: We examined the effect of intracameral administration of cefuroxime on oxidative stress and endothelial apoptosis in rat corneal tissue. METHODS: In total, 30 rats were divided into 3 groups of 10 rats each (intracameral administration of cefuroxime 0.1 mg/0.01 mL (cefuroxime group); intracameral administration of balanced salt solution 0.01 mL (control group); or absence of intracameral injection (sham group). Corneal endothelial apoptosis was assessed by immunohistochemical analysis using caspase-3 and caspase-8. Total oxidant status, total antioxidant status, oxidative stress index, and paraoxonase and arylesterase levels were examined in corneal endothelial tissue and serum. RESULTS: Paraoxonase levels in the serum were significantly different between the sham and cefuroxime groups (p=0.027). A significant difference was also observed in total oxidant status levels between the cefuroxime and balanced salt solution groups (p=0.023). In addition, there were significant differences in total antioxidant status levels in corneal tissue between the cefuroxime and sham groups (p<0.001) and between the cefuroxime and balanced salt solution groups (p<0.001). Furthermore, significant differences were also observed in oxidative stress index levels between the cefuroxime and balanced salt solution groups (p=0.001) and between the cefuroxime and sham groups (p=0.026). According to the immunohistochemical staining results, a significant association with caspase-3 activity existed between the cefuroxime and balanced salt solution groups (p=0.007), while no significant difference was found with caspase-8 activity (p=0.541). Caspase-3 activity exhibited a significant relationship between the sham and balanced salt solution groups (p=0.018), but no relationship was found with caspase-8 activity (p=0.623). CONCLUSION: Immunohistochemical examination revealed that intracameral cefuroxime increased apoptosis when compared to the sham and balanced salt solution groups. Moreover, intracameral cefuroxime increased oxidative stress in the cornea and simultaneously induced apoptosis.

Resumen Introducción: La paraoxonasa-1 (PON1) sérica asociada a las HDL presenta dos polimorfismos comunes en las posiciones 192 y 55. Estos polimorfismos se consideran determinantes para la capacidad de las HDL de proteger a las LDL de su modificación oxidativa. En este contexto, el genotipo de PON1 se ha asociado con enfermedades cerebrovasculares, que incluyen el infarto cerebral. Objetivo: Determinar las frecuencias alélicas y genotípicas de PON1-L55M y PON1- Q192R, así como las actividades enzimáticas de PON1 en sujetos con y sin infarto cerebral aterotrombótico. Métodos: Se incluyeron 28 personas con infarto cerebral aterotrombótico y 29 sin infarto. Las genotipificaciones se realizaron mediante PCR-RFLP y las fenotipificaciones mediante la medición de las actividades paraoxonasa y arilesterasa en suero. Resultados: Para el polimorfismo Q192R, las frecuencias alélicas (Q/R) fueron 0.46/0.54 y 0.48/0.52 (p= 0.843) para el grupo control y el grupo con infarto, respectivamente. Mientras que para el polimorfismo L55M, las frecuencias alélicas (L/M) fueron 0.81/0.19 para el grupo control y 0.78/0.22 para el grupo con infarto (p= 0.610). Los niveles de actividad paraoxonasa no fueron significativamente diferentes entre los grupos control y con infarto (450 vs. 348 Ul/mL, p= 0.093). Mientras que los niveles de actividad arilesterasa fueron significativamente diferentes entre los grupos estudiados (90 vs. 70 Ul/mL, p= 0.001), sin embargo, al ajustarla por regresión lineal múltiple, dejo de ser significativa. Conclusión: Los polimorfismos Q192R y L55M, y la actividad paraoxonasa de la PON1 no son factores de riesgo para el infarto cerebral aterotrombótico en este estudio.

Abstract Background: The serum paraoxonase-1 (PON1) associated to HDL presents two common polymorphisms in the positions 192 and 55. These polymorphisms are considered determinant of the capacity of HDL to protect LDL from their oxidative modification. In this context, the PON1 genotype has been associated with cardiovascular diseases, including stroke. Objective: To determine the allelic and genotypic frequencies of PON1 L55M and Q192R as well as the enzymatic activities of PON1 in subjects with and without atherothrombotic stroke. Methods: There were included 28 people with atherothrombotic stroke and 29 without stroke. The genotyping was carried out by PCR-RFLP and the phenotyping by measurement of the activities of paraoxonase and arylesterase in serum. Results: For the polymorphism Q192R, the allelic frequencies (Q/R) were 0.46/0.54 and 0.48/0.52 (p= 0.843) for the control group and the group with stroke, respectively. While for the polymorphism L55M, the allelic frequencies (L/M) were 0.81/0.19 for the control group, and 0.78/0.22 for the group with stroke (p= 0.610). The activity levels of paraoxonase were not significantly different between the control and stroke groups (450 vs. 348 UI/mL, p= 0.093) While the activity levels of arylesterase were significantly different between the studied groups (90 vs. 70 UI/mL, p= 0.001); however, upon adjustment by multiple linear regression, it was not longer significant. Conclusion: The polymorphisms Q192R and L55M, and the paraoxonase activity of PON1 are not risk factors for atherothrombotic stroke according to the results of this study.

Abstract Paraoxonase 1 (PON1) is a serum enzyme associated with high density lipoprotein (HDL) regulation through its paraoxonase and arylesterase activity. PON1 inhibits the oxidation of HDL and low density lipoprotein (LDL), and is involved in the pathogenesis of a variety of diseases including atherosclerosis. Conversely, mutations in the low density lipoprotein receptor (LDLR) result in failure of receptor mediated endocytosis of LDL leading to its elevated plasma levels and onset of familial hypercholesterolemia (FH). In the current study we investigated the role of PON1 polymorphisms rs662; c.575A > G (p.Gln192Arg) and rs854560; c.163T > A (p.Leu55Met) in a large family having FH patients harboring a functional mutation in LDLR. Genotypes were revealed by RFLP, followed by confirmation through Sanger sequencing. PON1 activity was measure by spectrophotometry. Our results show significantly reduced serum paraoxonase and arylesterase activities in FH patients compared with the healthy individuals of the family (p < 0.05). PON1 QQ192 genotype showed a significantly higher association with FH (p=0.0002). PON1 Q192 isoform was associated with reduced serum paraoxonase activity by in silico analysis and PON1 R192 exhibited higher serum paraoxonase and arylesterase activity than the other polymorphs. Our results highlight that the combination of LDLR mutations and PON1 MMQQ genotypes may lead to severe cardiac events.

Objective: Paraoxonase 1 (PON1), an esterase associated with high-density lipoproteins (HDL), has several polymorphisms: the PON1 Q192R polymorphism (coding region) is responsible for variations in the paraoxonase activity of the enzyme. The PON1 192R allele is considered a risk factor for developing cardiometabolic disorders in some populations. The aim of the present study is to determine the distribution of the PON1 Q192R polymorphism and its association with the lipid profile and APO A1 in an Andean population. Materials and methods: A descriptive, cross-sectional study involving 79 healthy adults (26 males and 53 females), residents of the district of Junín at 4105 m.a.s.l. The PCR/RFLP technique was used for the analysis of the PON1 Q192R polymorphism. The serum values of the lipid profile and APO A1, and the paraoxonase and arylesterase activities of the enzyme were determined. Results: The distribution of the genotypes for PON1192 was QQ 13.9%, QR 45.6% and RR 40.5%, and the most frequent allele was 192R 63%. The baseline and stimulated paraoxonase activities were different based on their genotypes, while the esterase activity of the enzyme was not influenced by the polymorphism. On the other hand, no association was found between the PON1 Q192R polymorphism and the lipid profile and APO A1. Conclusions: The high prevalence of the PON1 192R allele among the studied population probably indicates an important role in the development of cardiometabolic diseases

Objetivo: La paraoxonasa 1 (PON1), una esterasa asociada a las lipoproteínas de alta densidad (HDL), presenta diversos polimorfismos: el polimorfismo PON1 Q192R (región codificante) es el responsable de las variaciones de la actividad paraoxonasa de la enzima. El alelo PON1 192R es considerado un factor de riesgo para desarrollar trastornos cardiometabólicos en algunas poblaciones. El objetivo del presente estudio es determinar la distribución de los polimorfismos PON1 Q192R, y su asociación con el perfil lipidíco y APO A1 en una población andina. Materiales y métodos: Estudio descriptivo, transversal, en el que participaron 79 personas adultas (26 hombres y 53 mujeres), clínicamente sanas, residentes del distrito de Junín a 4105 msnm. Se empleó la técnica PCR/RFLP para el análisis del sitio polimórfico Q192R del gen PON1, y se determinaron los valores séricos del perfil lipídico y APO A1, y las actividades paraoxonasa y arilesterasa de la enzima. Resultados: La distribución de los genotipos para PON1192 fue: QQ 13,9%, QR 45,6% y RR 40,5%, y el alelo más frecuente fue 192R 63%. Las actividades paraoxonasa basal y estimulada fueron diferentes según sus genotipos, mientras que la actividad esterasa de la enzima no estuvo influenciada por el polimorfismo. Por otra parte, no se encontró asociación entre el polimorfismo PON1 Q192R y el perfil lipídico y APO A1. Conclusiones: La alta prevalencia del alelo PON1 192R en la población estudiada probablemente indique un papel importante en el desarrollo de enfermedades cardiometabólica

Abstract Objectives Oxidative stress and inflammation are important processes in development of atherosclerosis. Paraoxonase 1 (PON1) is a bioscavenger enzyme associated with inflammation and oxidative stress. We evaluate the association of two single nucleotide polymorphisms in PON1 gene, and enzyme activities with lipid profile and glycemia. Methods This case-control study consisted of 126 patients with coronary artery disease (CAD) and 203 healthy controls. PON Q192R and L55M polymorphisms were detected by real-time PCR. Paraoxonase and arylesterase activities were determined spectrophotometrically. Blood glucose, cholesterol, triglycerides, HDL, and LDL were measured. Results PON1 QR192 polymorphism had a major effect on paraoxonase but no effect on arylesterase serum activities. Paraoxonase activity was higher in RR genotype and lowest in QQ genotype. Paraoxonase and arylesterase activities were higher in LL and lower in MM genotypes of PON1 LM55 polymorphism. RQ and LM variants showed intermediate activities between respective homozygous. Elevated concentrations of triglycerides in cases correlate with QQ variant or the presence of M allele. Glucose levels were elevated in cases with QQ variant or with the presence of M allele. Cholesterol and LDL did not show variations in control and cases with any variant of both polymorphisms. HDL is lower in cases with respect to controls independently of genotypes. All differences were significant with p < 0.05. Conclusions Our results confirm the relationship between variations in PON1 activities and lipid metabolism, and showed that genetically programmed low PON1 activities would have certain responsibility in the increase in glycemia and concomitantly the aggravation of atherosclerotic disease.

Resumen Objetivos La enzima paraoxonasa 1 (PON1), está asociada con el estrés oxidativo y la inflamación, procesos importantes en el desarrollo de la aterosclerosis. Evaluamos la asociación de 2 polimorfismos de un solo nucleótido en el gen PON1 y sus actividades enzimáticas con el perfil lipídico y la glucemia. Métodos Estudio caso-control en 126 pacientes con enfermedad coronaria y 203 controles sanos. Los polimorfismos PON Q192R y L55M fueron detectados por PCR en tiempo real y las actividades de paraoxonasa y arilesterasa por espectrofotometría. Se midieron glucemia, colesterol, triglicéridos, HDL y LDL. Resultados El polimorfismo PON1 QR192 afectó la actividad de paraoxonasa pero no la de arilesterasa. La actividad de paraoxonasa fue mayor en el genotipo RR y menor en QQ. Ambas actividades fueron mayores en el genotipo LL y menores en MM del polimorfismo PON1 LM55. Las variantes RQ y LM mostraron actividades intermedias entre los respectivos homocigotos. Concentraciones elevadas de triglicéridos en los casos correlacionaron con la variante QQ o la presencia del alelo M. Los niveles de glucosa fueron elevados en los casos QQ o con la presencia del alelo M. El colesterol y el LDL no variaron ni en los casos ni en los controles con ambos polimorfismos. El HDL fue menor en los casos respecto de los controles, independientemente del genotipo. Conclusiones Los resultados confirman la relación entre las variaciones en las actividades de PON1 y el metabolismo lipídico y mostraron que las bajas actividades de PON1 genéticamente programadas tendrían cierta responsabilidad en el aumento de la glucemia y, concomitantemente, en la agravación de la enfermedad aterosclerótica.

OBJECTIVES: The aim of this study was to investigate the activities of serum paraoxonase and arylesterase in patients with ankylosing spondylitis with respect to those of healthy controls, to assess whether these enzyme levels are related to disease activity and functional capacity. METHODS: The study included 32 patients with ankylosing spondylitis whose diagnoses were made according to the modified New York criteria as well as 25 healthy controls matched for age and sex. The Bath Ankylosing Spondylitis Disease Activity Index and the Bath Ankylosing Spondylitis Functional Index were applied to the ankylosing spondylitis patients. As laboratory parameters, the erythrocyte sedimentation rate and serum C-reactive protein level were measured in patients and control subjects. Paraoxonase and arylesterase enzyme activities were measured using appropriate methods. RESULTS: No statistically significant differences (p>0.05) were found between the ankylosing spondylitis patients and controls in terms of serum paraoxonase or arylesterase levels. Furthermore, there was no correlation between clinical and laboratory parameters in patients with ankylosing spondylitis. CONCLUSION: Serum paraoxonase and arylesterase levels in ankylosing spondylitis patients may not differ from those of healthy controls, and there is no significant correlation between antioxidant parameters and the Bath Ankylosing Spondylitis Disease Activity Index or Bath Ankylosing Spondylitis Functional Index scores in ankylosing spondylitis patients. Further research is needed to provide deeper understanding of this disease.

Purpose: To determine the Paraoxonase-1 (PON1) activity as well as its pheno- and genotypes at position 192 in Mexican subjects with diagnosis of coronary heart disease (CHD). Methods: We determined the PON1-192 polymorphism by PCR-RFLP, and serum PON1 activity, using either paraoxon (PONase activity) or phenylacetate (ARE activity) as substrates, in 155 clinically healthy individuals (control group), and 155 patients with at least one myocardial infarction (CHD group). The biochemical A/B phenotype was determined by the ratio of the NaCI 1 M-stimulated PONase activity divided by the ARE activity. Results: We found significantly lower PONase and ARE activities in CHD patients as compared to controls (233.1 ± 102.1 vs 295.8 ± 159.1 nmol/min/mL, and 103.1 ± 33.7 vs 220.2 ± 120.7. micromol/min/mL, respectively, p < 0.05 for both). Alíele and genotype frequencies for PON1-192 were similar in CHD patients and healthy controls. Moreover, in the control group, the PON1-192 Q/R genotype did not matched with the A/B phenotype as has been proposed by other studies. Conclusions: There were important differences in the ARE and PONase activities between Mexican CHD patients and controls, suggesting that PON1 activity could be a good marker of CHD risk, whereas PON 1-192 lacks of value to assess such risk.

Propósito: Determinar la actividad de la enzima paraoxonasa-1 (PON1), y sus feno- y genotipos en posición 192 de la cadena de aminoácidos en sujetos mexicanos con diagnóstico de enfermedad arterial coronaria (EAC). Métodos: El polimorfismo de la PON1-192 se determinó por PCR-RFLP, y la actividad PON1 en suero se estableció utilizando dos substratos, paraoxón (actividad PONasa) o fenilacetato (denominada actividad ARE), en 155 individuos clínicamente sanos (grupo control), y en 155 pacientes con enfermedad cardiovascular que habían sufrido al menos un infarto (grupo EAC). Los sujetos en el estudio fueron clasificados de acuerdo a su fenotipo bioquímico como AA, AB y BB si el cociente de la actividad PONasa estimulada con NaCI 1M dividida por la actividad ARE era < 2, entre 2 y 8, y > 8, respectivamente. Resultados: Las actividades PONasa y ARE fueron significativamente menores en los pacientes con EAC en relación con los sujetos control (233.1 ± 102.1 vs 295.8 ± 159.1 nmol/ min/mL, y 103.1 ± 33.7 vs 220.2 ± 120.7 micro-mol/min/mL, respectivamente, p < 0.05 para ambos). Las frecuencias tanto alélicas como genotípicas de PON1-192 fueron similares en ambos grupos. Además, en nuestro estudio el genotipo PON1-192Q/R no corresponde con el fenotipo bioquímico A/B como se había propuesto anteriormente por otros autores. Conclusiones: Los sujetos mexicanos con EAC presentan actividades PON1 menores que los individuos control, sugiriendo que la actividad PON1, podría ser marcador de riesgo de EAC, mientras que el genotipo PON1-192 carece de valor informativo en la evaluación de dicho riesgo en esta población en particular.

Introduction: Plasma myeloperoxidase activity (MPO) (EC 1.11.1.7) has been related to several chronic-degenerative diseases such as asthma, which have in common a chronic inflammatory process. Paraoxonase (PON-1) (EC 3.1.1.2), is an arylesterase enzyme that has a hydroperoxide catalytic function. This enzyme is a component of APO A-l located in HDL. PON1 is has been considered to protect lipoproteins, because it interrupts the oxidation process of LDL, conducive to the atherosclerotic process. Objectives: To demonstrate that, a) oxidative stress in asthmatic patients correlates with the MPO activity, and b) demonstrate the role of PON 1 activity as a biomarker of their pulmonary function. Methods: The activity of both enzymes was measured in plasma of patients with asthma and compared to a control group of healthy subjects. Results: In the group of patients with asthma, MPO activity increased 42% (57.31 ± 7.2 U vs 33.34 ± 4.7 U p<0.05), while PON-1 activity decreased 52% (0.09 ±0.1 nmol p-nitrophenol/mg prot vs 0.05 ± 0.01 nmol p-nitrophenol/mg prot p<0.01). MPO activity showed an inverse correlation with FEV, with a Spearman r of -0.57, while PON-1 activiy showed a direct correlation with FEF25-75, Spearman r of0.64. Conclusions: In this study we show, for the first time, that asthma patients, in whom there is a state of oxidative stress that affects the pulmonary function, PON-1 determination can be useful as a predictor of a better pulmonary function, whereas an increment in MPO activity could be associated to an acute inflammatory process, implicating cellular damage. * U = U/mg of protein'.

Introducción: El incremento en la actividad de mieloperoxidasa (AAPO) (EC 1.11.1.7) plasmática ha sido relacionada con la evolución de diferentes patologías destacando las enfermedades crónico-degenerativas que tienen en común el cursar con un estado de estrés oxidativo (EO) concomitante a un proceso inflamatorio persistente. Este es el caso del asma. La enzima paraoxonasa (PON-1) (EC 3.1.1.2), es una arilesterasa que forma parte de la APO A-I de laa HDL. Su función catalítica le permite hidrolizar hidroperóxidos formados durante la lipoperoxídación de lipoproteínas y membranas como consecuencia de un EO. A la PON-1 se ha considerado como protectora de las lipoproteínas al interrumpir la oxidación de las LDL y disminuir el daño a estructuras celulares. Es una actividad enzimática que representa a la defensa antiestrés oxidativo. Objetivos: Demostrar que el estrés oxidativo del paciente asmático puede ser evaluado por el incremento de MPO como marcador de daño oxidante y que la función respiratoria adecuada puede ser relacionada con la capacidad de defensa antioxidante representada por la actividad de la PON-1. Métodos: La actividad de ambas enzimas fue determinada en el plasma de un grupo de pacientes con asma leve a moderada comparado con un grupo control formado por individuos clínicamente sanos. Resultados: En el grupo de pacientes con asma, la actividad de MPO se incrementó en un 42% (57.31 ± 7.2 U vs 33.34 ± 4.7 U p<0.05), mientras que se observó un decremento del 52% (0.09 ±0.1 nmol p-nitrofenol/mg prot vs 0.05 ± 0.01 nmol p-nitrofenol/mg prot p<0.01) en la actividad de la PON-1. La actividad de la MPO mostró una correlación inversamente proporcional con el FEV1 con una r de Spearman de -0.57 y la PON-1 mostró una correlación directamente proporcional con el FEF25-75 con una r de Spearman de 0.64. Conclusiones: Se demuestra por primera vez que los pacientes con asma, en los que se presenta un estado de estrés oxidativo que afecta la función pulmonar, la determinación de la PON1 puede servir como predictor de una mejor función pulmonar, mientras que el incremento en la actividad de MPO podría asociarse a un proceso inflamatorio activo con el concomitante daño celular. * U = U/mg de proteína