RESUMEN
BACKGROUND: This study evaluated the effects of concurrent isolated training (T) or training combined with the antioxidant N-acetylcysteine (NAC) on cardiac remodeling and oxidative stress in spontaneously hypertensive rats (SHR). METHODS: Six-month-old male SHR were divided into sedentary (S, n = 12), concurrent training (T, n = 13), sedentary supplemented with NAC (SNAC, n = 13), and concurrent training with NAC supplementation (TNAC, n = 14) groups. T and TNAC rats were trained three times a week on a treadmill and ladder; NAC supplemented groups received 120 mg/kg/day NAC in rat chow for eight weeks. Myocardial antioxidant enzyme activity and lipid hydroperoxide concentration were assessed by spectrophotometry. Gene expression of NADPH oxidase subunits Nox2, Nox4, p22 phox, and p47 phox was evaluated by real time RT-PCR. Statistical analysis was performed using ANOVA and Bonferroni or Kruskal-Wallis and Dunn. RESULTS: Echocardiogram showed concentric remodeling in TNAC, characterized by increased relative wall thickness (S 0.40 ± 0.04; T 0.39 ± 0.03; SNAC 0.40 ± 0.04; TNAC 0.43 ± 0.04 *; * p < 0.05 vs T and SNAC) and diastolic posterior wall thickness (S 1.50 ± 0.12; T 1.52 ± 0.10; SNAC 1.56 ± 0.12; TNAC 1.62 ± 0.14 * mm; * p < 0.05 vs T), with improved contractile function (posterior wall shortening velocity: S 39.4 ± 5.01; T 36.4 ± 2.96; SNAC 39.7 ± 3.44; TNAC 41.6 ± 3.57 * mm/s; * p < 0.05 vs T). Myocardial lipid hydroperoxide concentration was lower in NAC treated groups (S 210 ± 48; T 182 ± 43; SNAC 159 ± 33 *; TNAC 110 ± 23 *# nmol/g tissue; * p < 0.05 vs S, # p < 0.05 vs T and SNAC). Nox 2 and p22 phox expression was higher and p47 phox lower in T than S [S 1.37 (0.66-1.66); T 0.78 (0.61-1.04) *; SNAC 1.07 (1.01-1.38); TNAC 1.06 (1.01-1.15) arbitrary units; * p < 0.05 vs S]. NADPH oxidase subunits did not differ between TNAC, SNAC, and S groups. CONCLUSION: N-acetylcysteine supplementation alone reduces oxidative stress in untreated spontaneously hypertensive rats. The combination of N-acetylcysteine and concurrent exercise further decreases oxidative stress. However, the lower oxidative stress does not translate into improved cardiac remodeling and function in untreated spontaneously hypertensive rats.
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Acetilcisteína , Hipertensión , NADPH Oxidasas , Estrés Oxidativo , Ratas Endogámicas SHR , Remodelación Ventricular , Animales , Masculino , Estrés Oxidativo/efectos de los fármacos , Acetilcisteína/farmacología , Remodelación Ventricular/efectos de los fármacos , Hipertensión/fisiopatología , Hipertensión/tratamiento farmacológico , Hipertensión/metabolismo , NADPH Oxidasas/metabolismo , NADPH Oxidasas/genética , Ratas , Antioxidantes/farmacología , Condicionamiento Físico Animal , Modelos Animales de Enfermedad , NADPH Oxidasa 2/metabolismo , NADPH Oxidasa 2/genética , NADPH Oxidasa 4/metabolismo , NADPH Oxidasa 4/genética , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética , Miocardio/metabolismo , Miocardio/patología , Peróxidos Lipídicos/metabolismo , Función Ventricular Izquierda/efectos de los fármacos , Suplementos Dietéticos , Hipertrofia Ventricular Izquierda/fisiopatología , Hipertrofia Ventricular Izquierda/prevención & control , Hipertrofia Ventricular Izquierda/metabolismoRESUMEN
High levels of testosterone (Testo) are associated with cardiovascular risk by increasing reactive oxygen species (ROS) formation. NADPH oxidases (NOX) are the major source of ROS in the vasculature of cardiovascular diseases. NOX4 is a unique isotype, which produces hydrogen peroxide (H2O2), and its participation in cardiovascular biology is controversial. So far, it is unclear whether NOX4 protects from Testo-induced endothelial injury. Thus, we hypothesized that supraphysiological levels of Testo induce endothelial NOX4 expression to attenuate endothelial injury. Human mesenteric vascular endothelial cells (HMECs) and human umbilical vein endothelial cells (HUVEC) were treated with Testo (10-7 M) with or without a NOX4 inhibitor [GLX351322 (10-4 M)] or NOX4 siRNA. In vivo, 10-wk-old C57Bl/6J male mice were treated with Testo (10 mg/kg) for 30 days to study endothelial function. Testo increased mRNA and protein levels of NOX4 in HMECs and HUVECs. Testo increased superoxide anion (O2-) and H2O2 production, which were abolished by NOX1 and NOX4 inhibition, respectively. Testo also attenuated bradykinin-induced NO production, which was further impaired by NOX4 inhibition. In vivo, Testo decreased H2O2 production in aortic segments and triggered endothelial dysfunction [decreased relaxation to acetylcholine (ACh)], which was further impaired by GLX351322 and by a superoxide dismutase and catalase mimetic (EUK134). Finally, Testo led to a dysregulated endothelial cell migration, which was exacerbated by GLX351322. These data indicate that supraphysiological levels of Testo increase the endothelial expression and activity of NOX4 to counterbalance the deleterious effects caused by Testo in endothelial function.NEW & NOTEWORTHY By inducing ROS formation, high levels of testosterone play a major role in the pathogenesis of cardiovascular disease. NOXs are the major sources of ROS in the vasculature of cardiovascular diseases. Herein, we describe a novel compensatory mechanism by showing that NOX4 is a protective oxidant enzyme and counterbalances the deleterious effects of testosterone in endothelial cells by modulating hydrogen peroxide formation.
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Movimiento Celular , Endotelio Vascular , Células Endoteliales de la Vena Umbilical Humana , Peróxido de Hidrógeno , Ratones Endogámicos C57BL , NADPH Oxidasa 4 , Testosterona , Animales , Humanos , Masculino , Ratones , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Células Endoteliales/metabolismo , Células Endoteliales/efectos de los fármacos , Endotelio Vascular/metabolismo , Endotelio Vascular/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Peróxido de Hidrógeno/metabolismo , Peróxido de Hidrógeno/farmacología , NADPH Oxidasa 4/metabolismo , NADPH Oxidasa 4/genética , Especies Reactivas de Oxígeno/metabolismo , Testosterona/farmacología , Testosterona/metabolismoRESUMEN
Estrone (E1) constitutes the primary component in oral conjugated equine estrogens (CEEs) and serves as the principal estrogen precursor in the female circulation in the post-menopause. E1 induces endothelium-dependent vasodilation and activate PI3K/NO/cGMP signaling. To assess whether E1 mitigates vascular dysfunction associated with postmenopause and explore the underlying mechanisms, we examined the vascular effects of E1 in ovariectomized (OVX) rats, a postmenopausal experimental model. Blood pressure was measured using tail-cuff plethysmography, and aortic rings were isolated to assess responses to phenylephrine, acetylcholine (ACh), and sodium nitroprusside. Responses to ACh in rings pre-incubated with superoxide dismutase (SOD), catalase (CAT), or apocynin were also evaluated. Protein expression of SOD, CAT, NOX1, NOX2, and NOX4 was determined by Western blotting. E1 treatment resulted in decreased body weight and retroperitoneal fat, increased uterine weight, and prevented elevated blood pressure in the OVX group. Furthermore, E1 improved endothelium-dependent ACh vasodilation, activated compensatory antioxidant mechanisms - i.e. increased SOD and CAT antioxidant enzymes activity, and decreased NOX4 expression. This, in turn, helped prevent oxidative stress and endothelial dysfunction in OVX rats. Additionally, E1 treatment reversed the increased total LDL cholesterol observed in the OVX group. The findings underscore protective effects of E1 on the cardiovascular system, counteracting OVX-related oxidative stress and endothelial dysfunction in Wistar rats. E1 exhibits promising therapeutic benefits for managing cardiovascular health, particularly in postmenopausal conditions.
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Endotelio Vascular , Estrona , NADPH Oxidasa 4 , Ovariectomía , Ratas Wistar , Especies Reactivas de Oxígeno , Vasodilatación , Animales , Femenino , NADPH Oxidasa 4/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Vasodilatación/efectos de los fármacos , Estrona/farmacología , Presión Sanguínea/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , RatasRESUMEN
PURPOSE: To investigate the role of puerarin on renal fibrosis and the underlying mechanism in renal ischemia and reperfusion (I/R) model. METHODS: Rats were intraperitoneally injected with puerarin (50 or 100 mg/kg) per day for one week before renal I/R. The level of renal collagen deposition and interstitial fibrosis were observed by hematoxylin and eosin and Sirius Red staining, and the expression of α-smooth muscle actin (α-SMA) was examined by immunohistochemical staining. The ferroptosis related factors and TLR4/Nox4-pathway-associated proteins were detected by Western blotting. RESULTS: Puerarin was observed to alleviate renal collagen deposition, interstitial fibrosis and the α-SMA expression induced by I/R. Superoxide dismutase (SOD) activities and glutathione (GSH) level were decreased in I/R and hypoxia/reoxygenation (H/R), whereas malondialdehyde (MDA) and Fe2+ level increased. However, puerarin reversed SOD, MDA, GSH and Fe2+ level changes induced by I/R and H/R. Besides, Western blot indicated that puerarin inhibited the expression of ferroptosis related factors in a dose-dependent manner, which further demonstrated that puerarin had the effect to attenuate ferroptosis. Moreover, the increased expression of TLR/Nox4-pathway-associated proteins were observed in I/R and H/R group, but puerarin alleviated the elevated TLR/Nox4 expression. CONCLUSIONS: Our results suggested that puerarin inhibited oxidative stress and ferroptosis induced by I/R and, thus, delayed the progression of renal fibrosis, providing a new target for the treatment of renal fibrosis.
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Ferroptosis , Enfermedades Renales , Daño por Reperfusión , Ratas , Animales , Receptor Toll-Like 4/metabolismo , Estrés Oxidativo , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/prevención & control , Daño por Reperfusión/metabolismo , Isquemia , Fibrosis , Superóxido Dismutasa/metabolismo , NADPH Oxidasa 4/metabolismoRESUMEN
Capacitation is a series of physiological, biochemical, and metabolic changes experienced by mammalian spermatozoa. These changes enable them to fertilize eggs. The capacitation prepares the spermatozoa to undergo the acrosomal reaction and hyperactivated motility. Several mechanisms that regulate capacitation are known, although they have not been fully disclosed; among them, reactive oxygen species (ROS) play an essential role in the normal development of capacitation. NADPH oxidases (NOXs) are a family of enzymes responsible for ROS production. Although their presence in mammalian sperm is known, little is known about their participation in sperm physiology. This work aimed to identify the NOXs related to the production of ROS in guinea pig and mouse spermatozoa and define their participation in capacitation, acrosomal reaction, and motility. Additionally, a mechanism for NOXs' activation during capacitation was established. The results show that guinea pig and mouse spermatozoa express NOX2 and NOX4, which initiate ROS production during capacitation. NOXs inhibition by VAS2870 led to an early increase in the capacitation and intracellular concentration of Ca2+ in such a way that the spermatozoa also presented an early acrosome reaction. In addition, the inhibition of NOX2 and NOX4 reduced progressive motility and hyperactive motility. NOX2 and NOX4 were found to interact with each other prior to capacitation. This interaction was interrupted during capacitation and correlated with the increase in ROS. Interestingly, the association between NOX2-NOX4 and their activation depends on calpain activation, since the inhibition of this Ca2+-dependent protease prevents NOX2-NOX4 from dissociating and ROS production. The results indicate that NOX2 and NOX4 could be the most important ROS producers during guinea pig and mouse sperm capacitation and that their activation depends on calpain.
Asunto(s)
Calpaína , Especies Reactivas de Oxígeno , Semen , Capacitación Espermática , Animales , Cobayas , Masculino , Ratones , Calpaína/metabolismo , NADPH Oxidasa 4/metabolismo , NADPH Oxidasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Semen/metabolismo , Espermatozoides/metabolismoRESUMEN
Thyroid diseases are more prevalent in women, and this difference seems to be associated with the oxidative stress found in the thyroid of females. Thyroid NADPH Oxidase 4 (NOX4) was shown to respond to estrogen, which can also modulate TGF-ß1, a potent stimulator of NOX4. This study aimed to investigate the effects of TGF-ß1 on redox homeostasis parameters in the rat thyroid cell PCCL3 and the interrelationship between estrogen and TGF-ß1. TGF-ß1 treatment increased both intra- and extracellular ROS generation along with NOX4 expression and reduced GPX and catalase activities, extracellular H2O2 scavenging capacity, and reduced thiol content. TGF-ß1 mRNA and protein expression are higher in female thyroid glands of rats in comparison to males. Moreover, 17ß-estradiol treatment enhanced TGF-ß1 mRNA in PCCL3 cells, decreased extracellular bioavailability but did not activate Smad pathway. Our data suggest that higher levels of TGF-ß1 in females are potentially related to higher ROS availability which may be associated with the sex disparity in thyroid disorders.
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Glándula Tiroides , Factor de Crecimiento Transformador beta1 , Animales , Estrógenos/metabolismo , Femenino , Peróxido de Hidrógeno/metabolismo , Masculino , NADPH Oxidasa 4/genética , NADPH Oxidasa 4/metabolismo , NADPH Oxidasas/metabolismo , Oxidación-Reducción , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Especies Reactivas de Oxígeno/metabolismo , Caracteres Sexuales , Glándula Tiroides/metabolismo , Factor de Crecimiento Transformador beta1/genética , Factor de Crecimiento Transformador beta1/metabolismoRESUMEN
We addressed the involvement of the receptor for advanced glycation end products (RAGE) in the impairment of the cellular cholesterol efflux elicited by glycated albumin. Albumin was isolated from type 1 (DM1) and type 2 (DM2) diabetes mellitus (HbA1c > 9%) and non-DM subjects (C). Moreover, albumin was glycated in vitro (AGE-albumin). Macrophages from Ager null and wild-type (WT) mice, or THP-1 transfected with siRNA-AGER, were treated with C, DM1, DM2, non-glycated or AGE-albumin. The cholesterol efflux was reduced in WT cells exposed to DM1 or DM2 albumin as compared to C, and the intracellular lipid content was increased. These events were not observed in Ager null cells, in which the cholesterol efflux and lipid staining were, respectively, higher and lower when compared to WT cells. In WT, Ager, Nox4 and Nfkb1, mRNA increased and Scd1 and Abcg1 diminished after treatment with DM1 and DM2 albumin. In Ager null cells treated with DM-albumin, Nox4, Scd1 and Nfkb1 were reduced and Jak2 and Abcg1 increased. In AGER-silenced THP-1, NOX4 and SCD1 mRNA were reduced and JAK2 and ABCG1 were increased even after treatment with AGE or DM-albumin. RAGE mediates the deleterious effects of AGE-albumin in macrophage cholesterol efflux.
Asunto(s)
HDL-Colesterol/sangre , LDL-Colesterol/sangre , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Macrófagos/metabolismo , Receptor para Productos Finales de Glicación Avanzada/genética , Adulto , Animales , Estudios de Casos y Controles , Línea Celular , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patología , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patología , Femenino , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Regulación de la Expresión Génica , Hemoglobina Glucada/genética , Hemoglobina Glucada/metabolismo , Productos Finales de Glicación Avanzada/sangre , Productos Finales de Glicación Avanzada/farmacología , Humanos , Janus Quinasa 2/genética , Janus Quinasa 2/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , NADPH Oxidasa 4/genética , NADPH Oxidasa 4/metabolismo , Subunidad p50 de NF-kappa B/genética , Subunidad p50 de NF-kappa B/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Receptor para Productos Finales de Glicación Avanzada/antagonistas & inhibidores , Receptor para Productos Finales de Glicación Avanzada/deficiencia , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Albúmina Sérica Humana/metabolismo , Albúmina Sérica Humana/farmacología , Células THP-1 , Triglicéridos/sangreRESUMEN
We examined the effect of the NFκB inhibitor pyrrolidine-1-carbodithioic acid (PDTC) on inducible nitric oxide synthase (iNOS), matrix metalloproteinase-2 (MMP-2) activity, and oxidative and inflammatory kidney damage in alloxan-induced diabetes. Two weeks after diabetes induction (alloxan-130 mg/kg), control and diabetic rats received PDTC (100 mg/kg) or vehicle for 8 weeks. Body weight, glycemia, urea, and creatinine were measured. Kidney changes were measured in hematoxylin/eosin sections and ED1 by immunohistochemistry. Kidney thiobarbituric acid reactive substances (TBARS), superoxide anion (O2-), and nitrate/nitrite (NOx) levels, and catalase and superoxide dismutase (SOD) activities were analyzed. Also, kidney nox4 and iNOS expression, and NFkB nuclear translocation were measured by western blot, and MMP-2 by zymography. Glycemia and urea increased in alloxan rats, which were not modified by PDTC treatment. However, PDTC attenuated kidney structural alterations and macrophage infiltration in diabetic rats. While diabetes increased both TBARS and O2- levels, PDTC treatment reduced TBARS in diabetic and O2- in control kidneys. A decrease in NOx levels was found in diabetic kidneys, which was prevented by PDTC. Diabetes reduced catalase activity, and PDTC increased catalase and SOD activities in both control and diabetic kidneys. PDTC treatment reduced MMP-2 activity and iNOS and p65 NFκB nuclear expression found increased in diabetic kidneys. Our results show that the NFκB inhibitor PDTC reduces renal damage through reduction of Nox4, iNOS, macrophages, and MMP-2 in the alloxan-induced diabetic model. These findings suggest that PDTC inhibits alloxan kidney damage via antioxidative and anti-inflammatory mechanisms.
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Aloxano/toxicidad , Enfermedades Renales/tratamiento farmacológico , Metaloproteinasa 2 de la Matriz , NADPH Oxidasa 4/antagonistas & inhibidores , Óxido Nítrico Sintasa de Tipo II/antagonistas & inhibidores , Pirrolidinas/uso terapéutico , Tiocarbamatos/uso terapéutico , Animales , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Enfermedades Renales/inducido químicamente , Enfermedades Renales/enzimología , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , Inhibidores de la Metaloproteinasa de la Matriz/farmacología , Inhibidores de la Metaloproteinasa de la Matriz/uso terapéutico , NADPH Oxidasa 4/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Pirrolidinas/farmacología , Ratas , Ratas Wistar , Tiocarbamatos/farmacologíaRESUMEN
Angiotensin II exerts a cardinal role in the pathogenesis of hypertension and renal injury via action of angiotensin II type 1 (AT1) receptors. Local renin-angiotensin system (RAS) activity is essential for the mechanisms mediating pathophysiological functions. Proximal tubular angiotensinogen and tubular AT1 receptors are augmented by intrarenal angiotensin II. Caveolin 1 plays an important role as a regulatory molecule for the compartmentalization of redox signaling events through angiotensin II-induced NADPH oxidase activation in the kidney. A role for the renin-angiotensin system in the development and/or maintenance of hypertension has been demonstrated in spontaneously hypertensive rats (SHRs). Many effects of angiotensin II are dependent on the AT1 stimulation of reactive oxygen species (ROS) production by NADPH oxidase. Angiotensin II upregulation stimulates oxidative stress in proximal tubules from SHR. The NADPH oxidase 4 (Nox4) is abundantly expressed in kidney proximal tubule cells. Induction of the stress response includes synthesis of heat shock protein 70, a molecular chaperone that has a critical role in the recovery of cells from stress and in cytoprotection, guarding cells from subsequent insults. HSP70 chaperones function in part by driving the molecular triage decision, which determines whether proteins enter the productive folding pathway or result in client substrate ubiquitination and proteasomal degradation. This review examines regulation of losartan-mediated antioxidative stress responses by the chaperone HSP70 in proximal tubule cells of spontaneously hypertensive rats.
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Lesión Renal Aguda/tratamiento farmacológico , Antioxidantes/farmacología , Proteínas HSP70 de Choque Térmico/metabolismo , Hipertensión/tratamiento farmacológico , Losartán/farmacología , Angiotensina II/metabolismo , Animales , Túbulos Renales Proximales/efectos de los fármacos , Túbulos Renales Proximales/metabolismo , Túbulos Renales Proximales/patología , NADPH Oxidasa 4/metabolismo , Ratas , Ratas Endogámicas SHRRESUMEN
Asthma outcomes is aggravated in obese patients. Excess of methylglyoxal (MGO) in obese/diabetic patients has been associated with diverse detrimental effects on cell function. This study aimed to evaluate the effects of long-term oral intake of MGO on ovalbumin-induced eosinophil inflammation. Male C57/Bl6 mice received 0.5% MGO in the drinking water for 12 weeks. Mice were sensitized and challenged with ovalbumin (OVA), and at 48 h thereafter, bronchoalveolar lavage (BAL) fluid and lungs were collected for cell counting, morphological analysis, and ELISA, mRNA expressions and DHE assays. In MGO-treated mice, OVA challenge significantly increased the peribronchiolar infiltrations of inflammatory cells and eosinophils compared with control group. Higher levels of IL-4, IL-5, and eotaxin in BAL fluid were also detected in MGO compared with control group. In addition, lung tissue of MGO-treated mice displayed significant increases in mRNA expressions of NF-κB and iNOS whereas COX-2 expression remained unchanged. The high TNF-α mRNA expression observed in lungs of OVA-challenged control mice was not further increased by MGO treatment. In MGO group, OVA-challenge increased significantly the NOX-2 and NOX-4 mRNA expressions, without affecting the NOX-1 expression. Levels of reactive-oxygen species (ROS) were significantly higher in lungs of MGO-treated mice, and no further increase by OVA-challenge was observed. In conclusion, 12-week intake of MGO exacerbates Th2-mediated airway eosinophil infiltration by activation of NF-kB/iNOS-dependent signaling pathway and positive regulation of NOX-2 and NOX-4 in the lung tissues. Scavengers of MGO could be an option to prevent obesity-related asthma.
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Asma/metabolismo , Eosinófilos/inmunología , Obesidad/metabolismo , Piruvaldehído/metabolismo , Células Th2/inmunología , Alérgenos/inmunología , Animales , Movimiento Celular , Modelos Animales de Enfermedad , Humanos , Interleucina-4/metabolismo , Interleucina-5/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , NADPH Oxidasa 4/genética , NADPH Oxidasa 4/metabolismo , FN-kappa B/metabolismo , Ovalbúmina/inmunología , Especies Reactivas de Oxígeno/metabolismo , Transducción de SeñalRESUMEN
The aim of the study was to evaluate the time course of the effects of urban air pollutants on the ocular surface, focusing on the morphological changes, the redox balance, and the inflammatory response of the cornea. 8-week-old mice were exposed to urban or filtered air (UA-group and FA-group, respectively) in exposure chambers for 1, 2, 4, and 12â¯weeks. After each time, the eyes were enucleated and the corneas were isolated for biochemical analysis. UA-group corneas exhibited a continuous increase in NADPH oxidase-4 levels throughout the exposure time, suggesting an increased production of reactive oxygen species (ROS). After 1â¯week, an early adaptive response to ROS was observed as an increase in antioxidant enzymes. After 4â¯weeks, the enzymatic antioxidants were decreased, meanwhile an increase of the glutathione was shown, as a later compensatory antioxidant response. However, redox imbalance took place, evidenced by the increased oxidized proteins, which persisted up to 12â¯weeks. At this time point, corneal epithelium hyperplasia was also observed. The inflammatory response was modulated by the increase in IL-10 levels after 1â¯week, which early regulates the release of TNF-α and IL-6. These results suggest that air pollution alters the ocular surface, supported by the observed cellular hyperplasia. The redox imbalance and the inflammatory response modulated by IL-10 play a key role in the response triggered by air pollutants on the cornea. Taking into account this time course study, the ocular surface should also be considered as a relevant target of urban air pollutants.
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Contaminantes Atmosféricos/toxicidad , Contaminación del Aire/efectos adversos , Epitelio Corneal/patología , Animales , Brasil , Ciudades , Epitelio Corneal/efectos de los fármacos , Hiperplasia/inducido químicamente , Hiperplasia/patología , Interleucina-10/metabolismo , Masculino , Ratones , NADPH Oxidasa 4/metabolismo , Oxidación-Reducción/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Factores de Tiempo , Pruebas de Toxicidad Subaguda , Pruebas de Toxicidad SubcrónicaRESUMEN
Inflammation involves the activation of redox-sensitive transcription factors, e.g., nuclear factor κB (NF-κB). Administration of (-)-epicatechin to high-fructose-fed rats prevented NF-κB activation and up-regulation of the NADPH oxidase 4 (NOX4) in the kidney cortex. These results add mechanistic insights into the action of (-)-epicatechin diminishing inflammatory responses.
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Catequina/metabolismo , Fructosa/metabolismo , Corteza Renal/enzimología , NADPH Oxidasa 1/metabolismo , NADPH Oxidasa 4/metabolismo , FN-kappa B/metabolismo , Animales , Corteza Renal/metabolismo , Masculino , NADPH Oxidasa 1/genética , NADPH Oxidasa 2/genética , NADPH Oxidasa 2/metabolismo , NADPH Oxidasa 4/genética , FN-kappa B/genética , Ratas , Ratas Sprague-Dawley , Transducción de Señal , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismoRESUMEN
The development of obesity-related metabolic disorders is more evident in male in comparison with female subjects, but the mechanisms are unknown. Several studies have shown that oxidative stress is involved in the pathophysiology of obesity, but the majority of these studies were performed with male animals. The aim of this study was to evaluate the sex-related differences in subcutaneous adipose tissue redox homeostasis and inflammation of rats chronically fed a high-fat diet. NADPH oxidase (NOX), glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase activities were evaluated in the subcutaneous adipose tissue (SC) of adult male and female rats fed either a standard chow (SCD) or a high-fat diet (HFD) for 11 weeks. NOX2 and NOX4 messenger RNA (mRNA) levels, total reduced thiols, interleukin (IL)-1ß, tumor necrosis factor α (TNF-α), and IL-6 were also determined. Higher antioxidant enzyme activities and total reduced thiol levels were detected in SC of control male compared with female rats. Chronic HFD administration increased NOX activity and NOX2 and NOX4 mRNA levels and decreased SOD and GPx activities only in male animals. IL-1ß, TNF-α, and IL-6 levels, as well as Adgre1, CD11b, and CD68 mRNA levels, were also higher in SC of males after HFD feeding. In SC of females, catalase activity was higher after HFD feeding. Taken together, our results show that redox homeostasis and inflammation of SC is sexually dimorphic. Furthermore, males show higher oxidative stress in SC after 11 weeks of HFD feeding owing to both increased reactive oxygen species (ROS) production through NOX2 and NOX4 and decreased ROS detoxification.
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Dieta Alta en Grasa/efectos adversos , Homeostasis/fisiología , Inflamación/metabolismo , Grasa Subcutánea/metabolismo , Animales , Antioxidantes/metabolismo , Biomarcadores , Citocinas/sangre , Femenino , Masculino , NADPH Oxidasa 2/metabolismo , NADPH Oxidasa 4/metabolismo , Oxidación-Reducción , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Caracteres Sexuales , Grasa Subcutánea/citología , Compuestos de Sulfhidrilo/metabolismoRESUMEN
Ventricular arrhythmias are a common cause of sudden cardiac death, and their occurrence is higher in obese subjects. Abnormal gating of ryanodine receptors (RyR2), the calcium release channels of the sarcoplasmic reticulum, can produce ventricular arrhythmias. Since obesity promotes oxidative stress and RyR2 are redox-sensitive channels, we investigated whether the RyR2 activity was altered in obese mice. Mice fed a high fat diet (HFD) became obese after eight weeks and exhibited a significant increase in the occurrence of ventricular arrhythmias. Single RyR2 channels isolated from the hearts of obese mice were more active in planar bilayers than those isolated from the hearts of the control mice. At the molecular level, RyR2 channels from HFD-fed mice had substantially fewer free thiol residues, suggesting that redox modifications were responsible for the higher activity. Apocynin, provided in the drinking water, completely prevented the appearance of ventricular arrhythmias in HFD-fed mice, and normalized the activity and content of the free thiol residues of the protein. HFD increased the expression of NOX4, an isoform of NADPH oxidase, in the heart. Our results suggest that HFD increases the activity of RyR2 channels via a redox-dependent mechanism, favoring the appearance of ventricular arrhythmias.
Asunto(s)
Arritmias Cardíacas/etiología , Dieta Alta en Grasa/efectos adversos , Obesidad/complicaciones , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Disfunción Ventricular/etiología , Acetofenonas/uso terapéutico , Animales , Antiarrítmicos/uso terapéutico , Arritmias Cardíacas/tratamiento farmacológico , Masculino , Ratones , Ratones Endogámicos C57BL , Miocardio/metabolismo , NADPH Oxidasa 4/metabolismo , Obesidad/etiología , Especies Reactivas de Oxígeno/metabolismo , Disfunción Ventricular/tratamiento farmacológicoRESUMEN
Metabolic syndrome (MetS) is a risk factor for sudden cardiac death in humans, but animal models are needed for the study of this association. Grape pomace (GP), obtained from the winemaking process, contains phenolic compounds with potential cardioprotective effects. The aim of this study was to evaluate if a high-fat-fructose (HFF) diet facilitates the occurrence of arrhythmias during the reperfusion, and if a GP supplementation could counteract these effects. Wistar rats were fed with control (Ctrl), HFF diet and HFF plus GP (1 g kg-1 day-1) for six weeks. The HFF diet induces characteristic features of MetS (higher systolic blood pressure, dyslipidemia and insulin resistance) which was attenuated by GP supplementation. In addition, HFF induced increased reperfusion arrhythmias that were reduced upon GP supplementation. GP also reduced the non-phosphorylated form of connexin-43 (Cx43) while enhancing heart p-AKT and p-eNOS protein levels and reducing Nox4 levels enhanced by the HFF diet, indicating that GP may increase NO bioavailability in the heart. We found a murine model of MetS with increased arrhythmogenesis and translational value. Furthermore, GP prevents diet-induced heart dysfunction and metabolic alterations. These results highlight the potential utilization of winemaking by-products containing significant amounts of bioactive compounds to prevent/attenuate MetS-associated cardiovascular pathologies.
Asunto(s)
Arritmias Cardíacas/tratamiento farmacológico , Dieta Alta en Grasa/efectos adversos , Fructosa/efectos adversos , Preparaciones de Plantas/metabolismo , Vitis/química , Animales , Arritmias Cardíacas/etiología , Arritmias Cardíacas/genética , Arritmias Cardíacas/metabolismo , Conexina 43/genética , Conexina 43/metabolismo , Fructosa/metabolismo , Humanos , Masculino , Síndrome Metabólico/complicaciones , Síndrome Metabólico/genética , Síndrome Metabólico/metabolismo , NADPH Oxidasa 4/genética , NADPH Oxidasa 4/metabolismo , Ratas WistarRESUMEN
Diabetic cardiomyopathy refers to the manifestations in the heart as a result of altered glucose homeostasis, reflected as fibrosis, cellular hypertrophy, increased oxidative stress, and apoptosis, leading to ventricular dysfunction. Since physical exercise has been indicated as cardioprotective, we tested the hypothesis that high-intensity exercise training could reverse the cardiac maladaptations produced by diabetes. For this, diabetes was induced in rats by a single dose of alloxan. Diabetic rats were randomly assigned to a sedentary group or submitted to a program of exercise on a treadmill for 4 weeks at 80% of maximal performance. Another group of normoglycemic rats was used as control. Diabetic rat hearts presented cardiomyocyte hypertrophy and interstitial fibrosis. Chronic exercise reduced both parameters but increased apoptosis. Diabetes increased the myocardial levels of the mRNA and proteins of NADPH oxidases NOX2 and NOX4. These altered levels were not reduced by exercise. Diabetes also increased the level of uncoupled endothelial nitric oxide synthase (eNOS) that was not reversed by exercise. Finally, diabetic rats showed a lower degree of phosphorylated phospholamban and reduced levels of SERCA2 that were not restored by high-intensity exercise. These results suggest that high-intensity chronic exercise was able to reverse remodeling in the diabetic heart but was unable to restore the nitroso-redox imbalance imposed by diabetes.
Asunto(s)
Cardiomiopatías Diabéticas/metabolismo , Condicionamiento Físico Animal/fisiología , Animales , Apoptosis/fisiología , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatología , Cardiomiopatías Diabéticas/fisiopatología , Masculino , Miocardio/metabolismo , NADPH Oxidasa 2/metabolismo , NADPH Oxidasa 4/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Estrés Oxidativo/fisiología , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismoRESUMEN
Inorganic arsenic (iAs) exposure is related to cardiovascular disease, which is characterized by endothelial dysfunction and nitric oxide (NO) depletion. The mechanisms underlying NO depletion as related to iAs exposure are not fully understood. The endogenous inhibitor of nitric oxide synthase, asymmetric dimethylarginine (ADMA), might be a molecular target of iAs. ADMA concentrations are regulated by proteins involved in its synthesis (arginine methyl transferase 1 [PRMT-1]) and degradation (dimethylarginine dimethylaminohydrolase [DDAH]). Both, ADMA and NO are susceptible to oxidative stress. We aimed to determine the ADMA/DDAH/NO pathway in human vein endothelial cells (HUVEC-CS) exposed to arsenite. We exposed HUVEC-CS cells to 1, 2.5 and 5µM of arsenite for 24h. We proved that arsenite at 5µM was able to decrease NO levels with an associated increase in ADMA and depletion of l-arginine in HUVEC-CS cells. We also found a decrease in DDAH-1 protein expression with 5µM of arsenite compared to the control group. However, we did not observe significant differences in PRMT-1 protein expression at any of the concentrations of arsenite employed. Finally, arsenite (2.5 and 5µM) increased NADPH oxidase 4 protein levels compared with the control group. We conclude that ADMA, l-arginine and DDAH are involved in NO depletion produced by arsenite, and that the mechanism is related to oxidative stress.
Asunto(s)
Amidohidrolasas/metabolismo , Arginina/análogos & derivados , Arsenitos/toxicidad , Óxido Nítrico/metabolismo , Arginina/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , NADPH Oxidasa 4/metabolismo , Estrés Oxidativo/efectos de los fármacos , Proteína-Arginina N-Metiltransferasas/metabolismo , Proteínas Represoras/metabolismoRESUMEN
BACKGROUND: Overactivation of the aldosterone and mineralocorticoid receptor (MR) pathway is associated with hyperglycemia and dyslipidemia. Caveolin 1 (cav-1) is involved in glucose/lipid homeostasis and may modulate MR signaling. We investigated the interplay between cav-1 and aldosterone signaling in modulating insulin resistance and dyslipidemia in cav-1-null mice and humans with a prevalent variant in the CAV1 gene. METHODS AND RESULTS: In mouse studies, cav-1 knockout mice exhibited higher levels of homeostatic model assessment of insulin resistance, cholesterol, and resistin and lower ratios of high- to low-density lipoprotein (all P<0.001 versus wild type). Moreover, cav-1 knockout mice displayed hypertriglyceridemia and higher mRNA levels for resistin, retinol binding protein 4, NADPH oxidase 4, and aldose reductase in liver and/or fat tissues. MR blockade with eplerenone significantly decreased glycemia (P<0.01), total cholesterol (P<0.05), resistin (P<0.05), and described enzymes, with no effect on insulin or triglycerides. In the human study, we analyzed the CAV1 gene polymorphism rs926198 in 556 white participants; 58% were minor allele carriers and displayed higher odds of insulin resistance (odds ratio 2.26 [95% CI 1.40-3.64]) and low high-density lipoprotein (odds ratio 1.54 [95% CI 1.01-3.37]). Aldosterone levels correlated with higher homeostatic model assessment of insulin resistance and resistin and lower high-density lipoprotein only in minor allele carriers. CAV1 gene expression quantitative trait loci data revealed lower cav-1 expression in adipose tissues by the rs926198 minor allele. CONCLUSIONS: Our findings in mice and humans suggested that decreased cav-1 expression may activate the effect of aldosterone/MR signaling on several pathways of glycemia, dyslipidemia, and resistin. In contrast, hyperinsulinemia and hypertriglyceridemia are likely mediated by MR-independent mechanisms. Future human studies will elucidate the clinical relevance of MR blockade in patients with genotype-mediated cav-1 deficiency.