Bretschneider Solution and Two Antianginal Drugs Protect Peripheral Tissue in an Animal Model of Hemorrhagic Shock.

ABSTRACT: Shock and subsequent resuscitation provoke ischemia-reperfusion injury. Trimetazidine (TMZ), allopurinol (ALO), and histidine-tryptophan-ketoglutarate (HTK) solution, can protect from ischemia-reperfusion injury in chronic coronary syndromes and in transplantation. The objective of the current study is to compare, in a hemorrhagic shock and standard resuscitation animal model, organ damage parameters between placebo and treatment with TMZ, ALO, or HTK. Shock was induced in Wistar rats by controlled arterial bleeding, maintaining mean arterial pressure between 38 and 42 mm Hg for 60 minutes; then, drawn blood was reinfused. Animals were divided into: Sham (n = 4), Control (n = 6), TMZ (n = 7), ALO (n = 9), and HTK (n = 7). At the end of the experiment, animals were sacrificed and tissue harvested. TMZ, ALO and HTK decreased histopathologic damage in heart [Control: 1.72 (1.7-1.77); TMZ: 1.75 (1.72-1.79); ALO: 1.75 (1.74-1.8); HTK: 1.82 (1.78-1.85); all P < 0.05], kidney [Control: 3 (2-3); TMZ: 1 (1-2); ALO: 1 (1-1); HTK: 1(1-1); all P < 0.05] and intestine [Control: 3 (2-3); TMZ: 1 (1-2); ALO: 1 (1-1); HTK: 1 (0-2); all P < 0.05]. Also, treatment with TMZ, ALO, and HTK increased immunohistochemical expression of thioredoxin-1 in heart [Control: 6.6 (5.6-7.4); TMZ: 9.5 (8.1-9.7); ALO: 9.1 (8.4-10.2); HTK: 14.2 (12.6-15); all P < 0.05]; and kidney [Control: 4.6 (4-5.1); TMZ: 9.7 (9.3-9.9); ALO: 9.6 (9-9.9); HTK: 16.7 (16.1-17); all P < 0.05]. In an experimental model of hemorrhagic shock, TMZ, ALO, and HTK solution attenuated cell damage in multiple parenchyma and increased antioxidant defenses.

Assessing species reintroduction sites based on future climate suitability for food resources.

The reintroduction of a species that is extinct in the wild demands caution because reintroduction locations may be associated with threats, such as hunting, poor-quality habitat, and climate change. This is the case for Cyanopsitta spixii (Spix's Macaw), which has been extinct in the wild since 2000. The few living individuals were created in captivity and will be used in a reintroduction project within the species' original distribution area, the Caatinga domain (Brazil). Because the occurrence records for this bird are old and inaccurate, we investigated the current and future environmental suitability of the 14 plant species used by C. spixii as resource. These plants are key elements for the long-term reestablishment of the species in the wild, so the use of models helps in the assessment of the effects of climate change on the availability of these resources for the species and informs selection of the best places for reintroduction. We based our models of environmental suitability on 19 bioclimatic variables and nine physical soil and topography variables. Climate projections were created for the present and for the year 2070 with an optimistic (SSP2-4.5) and a pessimistic (SSP5-8.5) climate scenario. Both future climate scenarios lead to a reduction in area of environmental suitability that overlapped for all the plant species: 33% reduction for SSP2-4.5 and 63% reduction for SSP5-8.5. If our projections materialize, climate change could thus affect the distribution of key resources, and the maintenance of C. spixii would depend on restoration of degraded areas, especially riparian forests, and the preservation of already existing natural areas. The Caatinga domain is very threatened by habitat loss and, for the success of this reintroduction project, the parties involved must act to protect the species and the resources it uses.

Evaluación de los Sitios de Reintroducción de Especies con base en la Futura Idoneidad Climática para los Recursos Alimenticios Resumen La reintroducción de una especie que se encuentra extinta en vida libre exige precaución pues las localidades de reintroducción pueden estar asociadas con amenazas como la cacería, hábitats de mala calidad y el cambio climático. Éste es el caso para Cyanopsitta spixii (Guacamaya de Spix), que ha estado extinta en vida libre desde el 2000. Los pocos individuos vivos nacieron en cautiverio y se usarán para un proyecto de reintroducción dentro del área original de distribución de la especie: el dominio Caatinga (Brasil). Ya que los registros de la presencia de esta ave son viejos e imprecisos, investigamos la idoneidad ambiental actual y a futuro de 14 especies de plantas que C. spixii usa como recurso. Estas plantas son elementos importantes para el restablecimiento a largo plazo de las especies en vida silvestre, así que el uso de modelos asiste en la evaluación de los efectos del cambio climático sobre la disponibilidad de recursos para la especie e informa la selección de los mejores lugares para la reintroducción. Basamos nuestros modelos de la idoneidad ambiental en 19 variables bioclimáticas y 9 variables físicas del suelo y la topografía. Las proyecciones climáticas fueron creadas para el presente y para el año 2070 con un escenario climático optimista (SSP2-4.5) y uno pesimista (SSP5-8.5) Ambos escenarios climáticos futuros llevan a una reducción en el área de idoneidad ambiental sobrepuesta para todas las especies de plantas: 33% de reducción para SSP2-4.5 y 63% de reducción para SSP5-8.5. Si nuestras proyecciones se materializan, el cambio climático podría entonces afectar la distribución de los recursos importantes, por lo que la conservación de C. spixii dependería de la restauración de las áreas degradadas, especialmente los bosques riparios y la preservación de las áreas naturales existentes. El dominio Caatinga se encuentra muy amenazado por la pérdida del hábitat y, para el éxito de este proyecto de reintroducción, las partes involucradas deben actuar para proteger a la especie y los recursos que utiliza.

Structural changes in endocrine pancreas of male Wistar rats due to chronic cola drink consumption. Role of PDX-1.

AIM: The objective of this work was to analyze the structural changes of the pancreatic islets in rats, after 6 month consuming regular and light cola for 6 months. Also, we have analyzed the possible role of PDX-1 in that process. Finally, with the available knowledge, we propose a general working hypothesis that explains the succession of phenomena observed. Previously, we reported evidence showing that chronic cola consumption in rats impairs pancreatic metabolism of insulin and glucagon and produces some alterations typically observed in the metabolic syndrome, with an increase in oxidative stress. Of note It is worth mentioning that no apoptosis nor proliferation of islet cells could be demonstrated. In the present study, 36 male Wistar rats were divided into three groups to and given free access to freely drink regular cola (C), light cola (L), or water (W, control). We assessed the impact of the three different beverages in on glucose tolerance, lipid levels, creatinine levels and immunohistochemical changes addressed for the expression of insulin, glucagon, PDX-1 and NGN3 in islet cells, to evaluate the possible participation of PDX-1 in the changes observed in α and ß cells after 6 months of treatment. Moreover, we assessed by stereological methods, the mean volume of islets (Vi) and three important variables: the fractional ß -cell area, the cross-sectional area of alpha (A α-cell) and beta cells (A ß-cell), and the number of ß and α cell per body weight. Data were analyzed by two-way ANOVA followed by Bonferroni's multiple t-test or by Kruskal-Wallis test, then followed by Dunn's test (depending on distribution). Statistical significance was set at p<0.05. Cola drinking caused impaired glucose tolerance as well as fasting hyperglycemia (mean:148; CI:137-153; p<0.05 vs W) and an increase of in insulin immunolabeling (27.3±19.7; p<0.05 vs W and L). Immunohistochemical expression for PDX-1 was significantly high in C group compared to W (0.79±0.71; p<0.05). In this case, we observed cytoplasmatic and nuclear localization. Likewise, a mild but significant decrease of in Vi was detected after 6 months in C compared to W group (8.2±2.5; p<0.05). Also, we observed a significant decrease of in the fractional ß cell area (78.2±30.9; p<0.05) compared to W. Accordingly, a reduced mean value of islet α and ß cell number per body weight (0.05±0.02 and 0.08±0.04 respectively; both p<0.05) compared to W was detected. Interestingly, consumption of light cola increased the Vi (10.7±3.6; p<0.05) compared to W. In line with this, a decreased cross-sectional area of ß-cells was observed after chronic consumption of both, regular (78.2±30.9; p<0.05) and light cola (110.5±24.3; p<0.05), compared to W. As for, NGN3, it was negative in all three groups. Our results support the idea that PDX-1 plays a key role in the dynamics of the pancreatic islets after chronic consumption of sweetened beverages. In this experimental model, the loss of islets cells might be attributed to autophagy, favored by the local metabolic conditions and oxidative stress.

Cardiorenal Involvement in Metabolic Syndrome Induced by Cola Drinking in Rats: Proinflammatory Cytokines and Impaired Antioxidative Protection.

We report experimental evidence confirming renal histopathology, proinflammatory mediators, and oxidative metabolism induced by cola drinking. Male Wistar rats drank ad libitum regular cola (C, n = 12) or tap water (W, n = 12). Measures. Body weight, nutritional data, plasma glucose, cholesterol fractions, TG, urea, creatinine, coenzyme Q10, SBP, and echocardiograms (0 mo and 6 mo). At 6 months euthanasia was performed. Kidneys were processed for histopathology and immunohistochemistry (semiquantitative). Compared with W, C rats showed (I) overweight (+8%, p < 0.05), hyperglycemia (+11%, p < 0.05), hypertriglyceridemia (2-fold, p < 0.001), higher AIP (2-fold, p < 0.01), and lower Q10 level (-55%, p < 0.05); (II) increased LV diastolic diameter (+9%, p < 0.05) and volume (systolic +24%, p < 0.05), posterior wall thinning (-8%, p < 0.05), and larger cardiac output (+24%, p < 0.05); (III) glomerulosclerosis (+21%, p < 0.05), histopathology (+13%, p < 0.05), higher tubular expression of IL-6 (7-fold, p < 0.001), and TNFα (4-fold, p < 0.001). (IV) Correlations were found for LV dimensions with IL-6 (74%, p < 0.001) and TNFα (52%, p < 0.001) and fully abolished after TG and Q10 control. Chronic cola drinking induced cardiac remodeling associated with increase in proinflammatory cytokines and renal damage. Hypertriglyceridemia and oxidative stress were key factors. Hypertriglyceridemic lipotoxicity in the context of defective antioxidant/anti-inflammatory protection due to low Q10 level might play a key role in cardiorenal disorder induced by chronic cola drinking in rats.

Exercise Ameliorates Endocrine Pancreas Damage Induced by Chronic Cola Drinking in Rats.

PURPOSE: This study evaluates whether the daily practice of an exercise routine might protect from endocrine pancreas damage in cola drinking rats. METHODS: Forty-eight Wistar rats were randomly assigned to 4 groups depending on a) beverage consumption ad libitum, water (W) or cola beverage (C), and b) physical activity, sedentary (S) or treadmill running (R). Accordingly, 4 groups were studied: WS (water sedentary), WR (water runner), CS (cola sedentary) and CR (cola runner). Body weight, nutritional data, plasma levels of glucose, creatinine, total cholesterol and cholesterol fractions, and triglycerides (enzymocolorimetry), and systolic blood pressure (plethysmography) were measured. After 6 months, euthanasia was performed (overdose sodium thiopental). Pancreatic tissue was immediately excised and conventionally processed for morphometrical and immunohistochemical determinations. RESULTS: The effects of running and chronic cola drinking on pancreas morphology showed interaction (p<0.001) rather than simple summation. Cola drinking (CS vs WS) reduced median pancreatic islet area (-30%, 1.8 10(4) µm2 vs 2.58 10(4) µm2, p<0.0001) and median ß-cell mass (-43%, 3.81 mg vs 6.73 mg, p<0.0001), and increased median α/ß ratio (+49%, 0.64 vs 0.43, p< 0.001). In water drinking rats (WR vs WS), running reduced median α-cell mass (-48%, 1.48 mg vs 2.82 mg, p<0.001) and α/ß ratio (-56%, 0.19 vs 0.43, p<0.0001). Differently, in cola drinking rats (CR vs CS), running partially restored median islet area (+15%, 2.06 10(4) µm2 vs 1.79 10(4) µm2, p<0.05), increased median ß-cell mass (+47%, 5.59 mg vs 3.81 mg, p <0.0001) and reduced median α/ß ratio (-6%, 0.60 vs 0.64, p<0.05). CONCLUSION: This study is likely the first reporting experimental evidence of the beneficial effect of exercise on pancreatic morphology in cola-drinking rats. Presently, the increase of nearly 50% in ß cells mass by running in cola drinking rats is by far the most relevant finding. Moderate running, advisably indicated in cola consumers and patients at risk of diabetes, finds here experimental support.

Beneficial Effect of Moderate Exercise in Kidney of Rat after Chronic Consumption of Cola Drinks.

AIM: The purpose of this study was to investigate the effect of moderate intensity exercise on kidney in an animal model of high consumption of cola soft drinks. METHODS: Forty-eight Wistar Kyoto rats (age: 16 weeks; weight: 350-400 g) were assigned to the following groups: WR (water runners) drank water and submitted to aerobic exercise; CR (cola runners) drank cola and submitted to aerobic exercise; WS (water sedentary) and CS (cola sedentary), not exercised groups. The aerobic exercise was performed for 5 days per week throughout the study (24 weeks) and the exercise intensity was gradually increased during the first 8 weeks until it reached 20 meters / minute for 30 minutes. Body weight, lipid profile, glycemia, plasma creatinine levels, atherogenic index of plasma (AIP) and systolic blood pressure (SBP) were determined. After 6 months all rats were sacrificed. A kidney histopathological score was obtained using a semiquantitative scale. Glomerular size and glomerulosclerosis were estimated by point-counting. The oxidative stress and pro-inflammatory status were explored by immunohistochemistry. A one way analysis of variance (ANOVA) with Tukey-Kramer post-hoc test or the Kruskal-Wallis test with Dunn's post-hoc test was used for statistics. A value of p < 0.05 was considered significant. RESULTS: At 6 months, an increased consumption of cola soft drink was shown in CS and CR compared with water consumers (p<0.0001). Chronic cola consumption was associated with increased plasma triglycerides, AIP, heart rate, histopathological score, glomerulosclerosis, oxidative stress and pro-inflammatory status. On the other hand, moderate exercise prevented these findings. No difference was observed in the body weight, SBP, glycemia, cholesterol and plasma creatinine levels across experimental groups. CONCLUSIONS: This study warns about the consequences of chronic consumption of cola drinks on lipid metabolism, especially regarding renal health. Additionally, these findings emphasize the protective role of exercise training on renal damage.

Functional and morphological changes in endocrine pancreas following cola drink consumption in rats.

AIM: We report the effects of long-term cola beverage drinking on glucose homeostasis, endocrine pancreas function and morphology in rats. METHODS: Wistar rats drank: water (group W), regular cola beverage (group C, sucrose sweetened) or "light" cola beverage (group L, artificially sweetened). After 6 months, 50% of the animals in each group were euthanized and the remaining animals consumed water for the next 6 months when euthanasia was performed. Biochemical assays, insulinemia determination, estimation of insulin resistance (HOMA-IR), morphometry and immunohistochemistry evaluations were performed in pancreas. RESULTS: Hyperglycemia (16%, p<0.05), CoQ10 (coenzyme-Q10) decrease (-52%,p<0.01), strong hypertriglyceridemia (2.8-fold, p<0.01), hyperinsulinemia (2.4 fold, p<0.005) and HOMA-IR increase (2.7 fold, p<0.01) were observed in C. Group C showed a decrease in number of α cells (-42%, p<0.01) and ß cells (-58%, p<0.001) and a moderate increase in α cells' size after wash-out (+14%, p<0.001). Group L showed reduction in ß cells' size (-9%, p<0.001) and only after wash-out (L12) a 19% increase in size (p<0.0001) with 35% decrease in number of α cells (p<0.01). Groups C and L showed increase in α/ß-cell ratio which was irreversible only in C (α/ß = +38% in C6,+30% in C12, p<0.001vs.W6). Regular cola induced a striking increase in the cytoplasmic expression of Trx1 (Thioredoxin-1) (2.25-fold in C6 vs. W6; 2.7-fold in C12 vs. W12, p<0.0001) and Prx2 (Peroxiredoxin-2) (3-fold in C6 vs. W6; 2-fold in C12 vs. W12, p<0.0001). Light cola induced increase in Trx1 (3-fold) and Prx2 (2-fold) after wash-out (p<0.0001, L12 vs. W12). CONCLUSION: Glucotoxicity may contribute to the loss of ß cell function with depletion of insulin content. Oxidative stress, suggested by increased expression of thioredoxins and low circulating levels of CoQ10, may follow sustained hyperglycemia. A likely similar panorama may result from the effects of artificially sweetened cola though via other downstream routes.

Inhibición de la hipertrofia ventricular izquierda, normalización de la respuesta contráctil cardíaca y estrés oxidativo en hipertensión experimental / Inhibition of Left Ventricular Hypertrophy, Normalization of the Contractile Response and Oxidative Stress in Experimental Hypertension

Introducción y objetivos: La hipertrofia ventricular izquierda secundaria a hipertensión arterial se ha interpretado como un mecanismo de protección para reducir el estrés parietal y prevenir la insuficiencia cardíaca. Sin embargo, paradójicamente, su presencia se acompaña de un incremento de la morbimortalidad cardiovascular. El presente estudio se llevó a cabo con el propósito de evaluar si el tratamiento antihipertensivo crónico inhibe el desarrollo de hipertrofia ventricular izquierda y revierte el deterioro de la respuesta betaadrenérgica cardíaca y su posible relación con cambios en el metabolismo oxidativo del miocardio. Material y métodos: Ratas macho espontáneamente hipertensas (REH, 2 meses de edad) se distribuyeron en grupos (n grupo = 18) grupo según (mg/kg, v.o.): losartán 30 (L), hidralazina 11 (H), rosuvastatina 10 (R), carvedilol 20 (C), agua (control tratamiento). Control hipertensión: 18 ratas normotensas (Wistar-Kyoto, WKY). Periódicamente se registraron la presión arterial sistólica (PAS) (pletismografía, en animales despiertos) y el peso corporal (PC). Luego de 16 meses se practicó eutanasia. El 50% de los corazones se montaron en preparación de Langendorff para medir contractilidad preestímulo y posestímulo betaadrenérgico [isoproterenol (Iso): 10-9M, 10-7M, 10-5M]. En los corazones restantes se registró el peso del ventrículo izquierdo (PVI), que se normalizó por el PC. Se cuantificó la expresión inmunohistoquímica de tiorredoxina 1(Trx-1), peroxirredoxina 2 (Prx-2) y glutarredoxina 3 (Grx-3) (indicadores antioxidantes). Resultados: Peso corporal: similar en todos los grupos. PAS (mm Hg): 154 ± 3 (L), 137 ± 1 (H), 190 ± 3 (R)**, 206 ± 3 (REH)*, 183 ± 1 (C)**, 141 ± 1 (WKY) (*p < 0,05 vs. L, H, WKY; **p < 0,05 vs. L, H, WKY, REH). El PVI/PC de REH y R fue mayor (p < 0,05) respecto de L, H, C y WKY. En C no se observó correlación entre hipertensión e hipertrofia ventricular izquierda. Grupos REH, R y C: mostraron depresión de contractilidad basal vs. L, H y WKY. Respuesta a Iso 10-5 M: similar en WKY y L; disminuida en C, H, R y REH. Expresión de Trx-1, Prx-2 y Grx-3: aumentó en C, H, R y L (1,5-2 veces promedio; p < 0,01 vs. REH y WKY). Conclusiones: El tratamiento con losartán, hidralazina y carvedilol previno el desarrollo de hipertrofia ventricular izquierda. El losartán normalizó la respuesta al isoproterenol en REH. Factores adicionales participarían en el desarrollo de hipertrofia ventricular izquierda con deterioro de la respuesta inotrópica a la estimulación betaadrenérgica en hipertensión. El aumento en la expresión de tiorredoxinas por tratamientos antihipertensivos sugiere un beneficio asociado, aumentando la respuesta antioxidante frente al estrés oxidativo en hipertensión.

Background and objectives: Left ventricular hypertrophy secondary to hypertension has been perceived as a protective mechanism to reduce wall stress and prevent heart failure. However, its presence is paradoxically associated with increased cardiovascular morbidity and mortality The aim of this study was to evaluate whether chronic antihypertensive treatment inhibits the development of left ventricular hypertrophy and normalize the reverting impaired cardiac beta-adrenergic response, and its possible association with changes in myocardial oxidative metabolism. Methods: Spontaneously hypertensive male rats (SHR, 2 months old) were divided into groups (n grupo = 18) according to (mg/ group kg, p.o): losartan 30 (L), hydralazine-11 (H), rosuvastatin 10 (R), carvedilol 20 (C), and water (control treatment). The control hypertension group consisted of 18 normotensive rats (Wistar-Kyoto, WKY). Systolic blood pressure (SBP) (plethysmography in awake animals) and body weight (BW) were measured periodically. The animals were sacrificed at 16 months and 50% of the hearts were mounted in a Langendorff system to measure contractility before and after beta-adrenergic stimulation [isoproterenol (Iso): 10-9 M, 10-7 M, and 10-5 M]. In the remaining hearts left ventricular weight (LVW) was measured and normalized by B W. Immunohistochemical expression of thioredoxin 1 (Trx-1), peroxyredoxin 2 (Prx-2) and glutaredoxin 3 (Grx-3) (antioxidant indicators) was quantified. Results: Body weight was similar in all groups. Systolic blood pressure (mm Hg) was 154 ± 3 (L), 137 ± 1 (H), 190 ± 3 (R)**, 206 ± 3 (SHR)*, 183 ± 1 (C)**, and 141 ± 1 (WKY) (* p < 0.05 vs. L, H, WKY, ** p < 0.05 vs. L, H, WKY, SHR). LVW/BW was higher in SHR and R (p < 0.05) compared with L, H, C and WKY. In C, there was no correlation between hypertension and left ventricular hypertrophy. SHR, R and C evidenced baseline contractile depression vs. L, H and WKY. The response to 10-5 M Iso was similar in WKY and L, and reduced in C, H, R and SHR. The expression of Trx-1, Prx-2 and Grx-3 increased in C, H, R and L (average increase: 1.5-2 times; p < 0.01 vs. SHR and WKY). Conclusions: Treatment with losartan, hydralazine, and carvedilol prevented the development of left ventricular hypertrophy. Losartan normalized the response to isoproterenol in SHR. Additional factors might participate in the development of left ventricular hypertrophy with impaired inotropic response to beta-adrenergic stimulation in hypertension. The increased ex-pression of thioredoxins as a result of antihypertensive treatment suggests an additional benefit, increasing the antioxidant response against oxidative stress in hypertension.

Inhibición de la hipertrofia ventricular izquierda, normalización de la respuesta contráctil cardíaca y estrés oxidativo en hipertensión experimental / Inhibition of Left Ventricular Hypertrophy, Normalization of the Contractile Response and Oxidative Stress in Experimental Hypertension

Introducción y objetivos: La hipertrofia ventricular izquierda secundaria a hipertensión arterial se ha interpretado como un mecanismo de protección para reducir el estrés parietal y prevenir la insuficiencia cardíaca. Sin embargo, paradójicamente, su presencia se acompaña de un incremento de la morbimortalidad cardiovascular. El presente estudio se llevó a cabo con el propósito de evaluar si el tratamiento antihipertensivo crónico inhibe el desarrollo de hipertrofia ventricular izquierda y revierte el deterioro de la respuesta betaadrenérgica cardíaca y su posible relación con cambios en el metabolismo oxidativo del miocardio. Material y métodos: Ratas macho espontáneamente hipertensas (REH, 2 meses de edad) se distribuyeron en grupos (n grupo = 18) grupo según (mg/kg, v.o.): losartán 30 (L), hidralazina 11 (H), rosuvastatina 10 (R), carvedilol 20 (C), agua (control tratamiento). Control hipertensión: 18 ratas normotensas (Wistar-Kyoto, WKY). Periódicamente se registraron la presión arterial sistólica (PAS) (pletismografía, en animales despiertos) y el peso corporal (PC). Luego de 16 meses se practicó eutanasia. El 50% de los corazones se montaron en preparación de Langendorff para medir contractilidad preestímulo y posestímulo betaadrenérgico [isoproterenol (Iso): 10-9M, 10-7M, 10-5M]. En los corazones restantes se registró el peso del ventrículo izquierdo (PVI), que se normalizó por el PC. Se cuantificó la expresión inmunohistoquímica de tiorredoxina 1(Trx-1), peroxirredoxina 2 (Prx-2) y glutarredoxina 3 (Grx-3) (indicadores antioxidantes). Resultados: Peso corporal: similar en todos los grupos. PAS (mm Hg): 154 ± 3 (L), 137 ± 1 (H), 190 ± 3 (R)**, 206 ± 3 (REH)*, 183 ± 1 (C)**, 141 ± 1 (WKY) (*p < 0,05 vs. L, H, WKY; **p < 0,05 vs. L, H, WKY, REH). El PVI/PC de REH y R fue mayor (p < 0,05) respecto de L, H, C y WKY. En C no se observó correlación entre hipertensión e hipertrofia ventricular izquierda. Grupos REH, R y C: mostraron depresión de contractilidad basal vs. L, H y WKY. Respuesta a Iso 10-5 M: similar en WKY y L; disminuida en C, H, R y REH. Expresión de Trx-1, Prx-2 y Grx-3: aumentó en C, H, R y L (1,5-2 veces promedio; p < 0,01 vs. REH y WKY). Conclusiones: El tratamiento con losartán, hidralazina y carvedilol previno el desarrollo de hipertrofia ventricular izquierda. El losartán normalizó la respuesta al isoproterenol en REH. Factores adicionales participarían en el desarrollo de hipertrofia ventricular izquierda con deterioro de la respuesta inotrópica a la estimulación betaadrenérgica en hipertensión. El aumento en la expresión de tiorredoxinas por tratamientos antihipertensivos sugiere un beneficio asociado, aumentando la respuesta antioxidante frente al estrés oxidativo en hipertensión.(AU)

Background and objectives: Left ventricular hypertrophy secondary to hypertension has been perceived as a protective mechanism to reduce wall stress and prevent heart failure. However, its presence is paradoxically associated with increased cardiovascular morbidity and mortality The aim of this study was to evaluate whether chronic antihypertensive treatment inhibits the development of left ventricular hypertrophy and normalize the reverting impaired cardiac beta-adrenergic response, and its possible association with changes in myocardial oxidative metabolism. Methods: Spontaneously hypertensive male rats (SHR, 2 months old) were divided into groups (n grupo = 18) according to (mg/ group kg, p.o): losartan 30 (L), hydralazine-11 (H), rosuvastatin 10 (R), carvedilol 20 (C), and water (control treatment). The control hypertension group consisted of 18 normotensive rats (Wistar-Kyoto, WKY). Systolic blood pressure (SBP) (plethysmography in awake animals) and body weight (BW) were measured periodically. The animals were sacrificed at 16 months and 50% of the hearts were mounted in a Langendorff system to measure contractility before and after beta-adrenergic stimulation [isoproterenol (Iso): 10-9 M, 10-7 M, and 10-5 M]. In the remaining hearts left ventricular weight (LVW) was measured and normalized by B W. Immunohistochemical expression of thioredoxin 1 (Trx-1), peroxyredoxin 2 (Prx-2) and glutaredoxin 3 (Grx-3) (antioxidant indicators) was quantified. Results: Body weight was similar in all groups. Systolic blood pressure (mm Hg) was 154 ± 3 (L), 137 ± 1 (H), 190 ± 3 (R)**, 206 ± 3 (SHR)*, 183 ± 1 (C)**, and 141 ± 1 (WKY) (* p < 0.05 vs. L, H, WKY, ** p < 0.05 vs. L, H, WKY, SHR). LVW/BW was higher in SHR and R (p < 0.05) compared with L, H, C and WKY. In C, there was no correlation between hypertension and left ventricular hypertrophy. SHR, R and C evidenced baseline contractile depression vs. L, H and WKY. The response to 10-5 M Iso was similar in WKY and L, and reduced in C, H, R and SHR. The expression of Trx-1, Prx-2 and Grx-3 increased in C, H, R and L (average increase: 1.5-2 times; p < 0.01 vs. SHR and WKY). Conclusions: Treatment with losartan, hydralazine, and carvedilol prevented the development of left ventricular hypertrophy. Losartan normalized the response to isoproterenol in SHR. Additional factors might participate in the development of left ventricular hypertrophy with impaired inotropic response to beta-adrenergic stimulation in hypertension. The increased ex-pression of thioredoxins as a result of antihypertensive treatment suggests an additional benefit, increasing the antioxidant response against oxidative stress in hypertension.(AU)

Las bebidas cola aceleran el crecimiento de la placa aterosclerótica en ratones ApoE-/- / Cola Beverages Accelerate Growth of the Atherosclerotic Plaque in ApoE-/- Mice

Introducción Los hábitos de alimentación poco saludables durante la infancia y la juventud se han suge­rido como favorecedores de las complicaciones ateroscleróticas en edades más avanzadas. El creciente consumo de bebidas cola en las últimas décadas se ha asociado con el desarrollo de obesidad e incremento en la incidencia de aterosclerosis y enfermedades cardiovasculares. A su vez, se sabe que existe correspondencia entre el consumo de estas bebidas y etapas de la vida, el cual es mayor en los niños, los adolescentes y los adultos jóvenes. Objetivo Evaluar el efecto del consumo de bebidas cola sobre la aterosclerosis. Material y métodos Se distribuyeron ratones ApoE-/- (8 semanas de edad) en tres grupos según el consumo libre de agua (A), bebida cola azucarada (C) y bebida cola edulcorada light (L). Al cabo de 8 semanas las bebidas cola se reemplazaron por agua. Los ratones fueron sacrificados secuencialmente: antes del tratamiento (8 semanas de edad) y luego de su interrupción (16, 20, 24 y 30 semanas de edad). Se extrajeron la aorta ascendente y el hígado. Se calculó la relación entre el área de la placa aórtica y el espesor de la capa media (relación placa/media). Se evaluó la inflamación del parénquima hepático según la escala de NASH. Resultados La relación placa/media varió según la bebida (F2,54 = 3,433, p < 0,04) y la edad (F4,54 = 5,009, p < 0,03) y fue mayor en los grupos C y L (p < 0,05 a las 16 y 20 semanas, p < 0,01 a las 24 y 30 semanas). La inflamación del parénquima hepático (F2,9 = 13,29, p < 0,002) y portal (F2,9 = 6,30, p < 0,02) aumentó cinco y dos veces, respectivamente, en función del tiempo (p < 0,01 y p < 0,03) entre las semanas 20 y 30, en contraste con la esteatosis y el daño hepatocelular, que no se modificaron. El grupo A (evolución natural de la aterosclerosis) se caracterizó por la aceleración del crecimiento del área de placa en paralelo con un rápido aumento de la inflamación hepática alrededor de la semana 20. Conclusiones El consumo de bebidas cola en ratones ApoE-/- entre las semanas 8 y 16 de edad aumentó la tasa de progresión de la aterosclerosis. Los datos sugieren que, en este modelo murino, el consumo sostenido de bebidas cola durante las etapas tempranas de la vida puede acelerar el agravamiento del daño aterosclerótico en etapas más tardías.

Cola Beverages Accelerate Growth of the Atherosclerotic Plaque in ApoE-/- Mice Introduction Unhealthy eating habits during childhood and youth have been suggested as predisposing factors to atherosclerotic complications later in life. The growing consumption of cola beverages in recent decades has been associated with the development of obesity and increased incidence of atherosclerosis and cardiovascular disease. We also know that there is a correspondence between the consumption of these beverages and the different stages of life, being higher in children, adolescents and young adults. Objective This study evaluates the effect of cola beverage consumption on atherosclerosis. Methods ApoE-/- mice (8 week-old) were randomized into 3 groups according to free access to water (W), sucrose sweetened carbonated cola drink (C) or aspartame-acesulfame K sweetened carbonated 'light' cola drink (L). At 8 weeks cola beverages were switched to water. The mice were sequentially euthanized: before treatment (8 week old mice) and after treatment discontinuation (20, 24, and 30 week old mice). The ascending aorta and the liver were removed. Aortic plaque area was analyzed and plaque/media-ratio was calculated. Hepatic inflammation was assessed according to the NASH scale. Results Plaque/media-ratio varied according to drink treatment (F2,54=3.433, p <0.04) and age (F4,54=5.009, p <0.03) and was higher in the C and L groups (p <0.05 at 16 and 20 weeks, p <0.01 at 24 and 30 weeks). Hepatic parenchymal inflammation (F2,9=13.29, p <0.002) and portal inflammation (F2,9 =6.30, p <0.02) varied fivefold and twofold in contrast to steatosis and hepatocellular damage which remained unchanged throughout the study.Natural evolution of atherosclerosis in ApoE-/- mice (W group) evidenced acceleration of plaque growth in parallel with a rapid increase in hepatic inflammation around week 20 of age. Conclusions Cola beverage consumption in 8-16 week old ApoE-/- mice accelerated atherosclerosis progression. Data suggest that, in this murine model, sustained cola consumption at early stages of life may predispose to atherosclerosis progression later in life.

Metabolic disturbances and worsening of atherosclerotic lesions in ApoE-/- mice after cola beverages drinking.

BACKGROUND: Atherosclerosis is a major health burden. Metabolic disorders had been associated with large consumption of soft drinks. The rising incidence of atherosclerosis and metabolic alterations warrants the study of long-term soft drink consumption' effects on metabolism and atherosclerosis in genetic deficiency of apolipoprotein E which typically develops spontaneous atherosclerosis and metabolic alterations. METHODS: ApoE-/- mice were randomized in 3 groups accordingly with free access to: water (W), regular cola (C) or light cola (L). After 8 weeks, 50% of the animals in each group were euthanized ( TREATMENT: W8, C8, L8). The remaining mice (all groups) drank water for 8 weeks and were euthanized (Washout: W16, C16, L16). Body weight and food and drink consumption were periodically measured. Blood was collected (biochemistry). At autopsy, transverse aortic sinus sections were serially cut and stained (histomorphometry); livers and kidneys were processed (microscopy). MANOVA (identification of variance factors) was followed by ANOVA and LSD tests (within-factor differences between levels). Conventionally a p< 0.05 was considered significant. RESULTS: TREATMENT increased drinking volumes (vs W8: 4 fold C8, p<0.0001; +47% L8, p<0.02). Only C reduced eating amounts (-54%, p<0.05 vs W8). I). Compared with W8: C8 developed hyperglycemia (+43%, p<0.03) and increased non-HDL cholesterol (+54%, p<0.05); L8 showed decreased glycemia (-15%, p<0.05 vs W8) and increased creatinine (2.5 fold, p<0.04), urea (+74, p<0.03) and aspartate-aminotransferase (2.8 fold, p<0.05). Hypercreatininemia was observed in L16 (2.7 fold vs W16, p<0.05). Hypertriglyceridemia (+91%, p<0.008) and hyperuremia (+68%, p<0.03) developed over time of study (age). II). TREATMENT caused plaque area increase (vs W8: 28% C8, p<0.02 and 50% L8, p<0.01; vs W16: 43% C16, p<0.05 and 68% L16, p<0.02) and stenosis (vs W8: 38% C8, p<0.04 and 57% L8, p<0.01; vs W16: 71% C16, p<0.01 and 46% L16, p<0.04). Age also caused plaque area increase (56%, p<0.04). TREATMENT- and age-effects on plaque enlargement were additive. CONCLUSION: Cola beverages caused atherosclerotic lesions' enlargement with metabolic (C) or non metabolic disturbances (L). ApoE-/- mice were particularly sensitive to L treatment. These findings may likely relate to caramel colorant and non-nutritive sweeteners in cola drinks and have potential implications in particularly sensitive individuals.

Transforming growth factor ß1 and coronary intimal hyperplasia in pediatric patients with congenital heart disease.

BACKGROUND: Congenital heart defects or the process of their repair leads to an increased risk for adult cardiovascular disease compared with the general population. Intimal hyperplasia is a preatherosclerotic lesion that may be produced as a consequence of transforming growth factor ß1 (TGF-ß1) pathway activation. We studied the presence of intimal hyperplasia in arteries from a pediatric population with congenital heart disease (CHD) and TGF-ß1 expression to enlighten its possible role in the genesis of these lesions. METHODS: Coronary arteries from 10 controls and 98 CHD patients (54% cyanotic type, 32% surgically repaired) were stained, and the presence and degree of intimal thickening were analyzed. The expression of TGF-ß1 was studied by immunohistochemistry. RESULTS: The difference between the presence of coronary intimal hyperplasia in patients with cyanotic (35; 66.1%) and noncyanotic CHD (29; 64.3%) was not significant. However, surgically repaired CHD presented a higher rate of coronary intimal hyperplasia (80%) than did the group without surgical intervention (47.3%), P = 0.0002. The immunostaining for TGF-ß1 analyzed in samples of patients with cyanotic and noncyanotic CHD showed no significant differences. However, TGF-ß1 expression was more intense on the intimal layer of patients with surgically repaired CHD than on that of those without surgery (intimal area positive for TGF-ß1, 50.43% vs 15.91%, respectively; Mann-Whitney U test P = 0.0005). CONCLUSION: The high incidence of intimal hyperplasia in patients with surgically repaired CHD is correlated with TGF-ß1 expression and may contribute to the development of atherosclerotic coronary artery disease in CHD patients.

Effect of chronic inhibition of converting enzyme on proximal tubule acidification.

The acute effect of angiotensin-converting enzyme inhibition (ACEi) on proximal convoluted tubule (PCT) function is well documented. However, the effect of chronic treatment is less known. The aim of this work was to evaluate the effect of chronic ACEi on PCT acidification (J(HCO(3)(-))). Rats received enalapril (10 mg.kg(-1).day(-1), added to the drinking water) during 3 mo. Micropuncture experiments were performed to measure the effect of chronic ACEi on J(HCO(3)(-)). Nitric oxide (NO.) synthesis in kidney cortex homogenates was assessed by quantifying the conversion of [(14)C]-L-arginine to [(14)C]-L-citrulline. Western blot analysis was performed to determine the abundances of V-H(+)ATPase and NHE3 isoform of the Na(+)/H(+) exchanger in proximal brush-border membrane vesicles (BBMV). Enalapril treatment induced an approximately 50% increase in J(HCO(3)(-)). Luminal perfusion with ethyl-isopropyl amiloride (EIPA) 10(-4)M or bafilomycin 10(-6)M decreased J(HCO(3)(-)) by approximately 60% and approximately 30%, respectively, in both control and enalapril-treated rats. The effect of EIPA and bafilomycin on absolute J(HCO(3)(-)) was larger in enalapril-treated than in control rats. Acute inhibition of NO. synthesis with N(G)-nitro-L-arginine methyl ester abolished the enalapril-induced increase in J(HCO(3)(-)). Cortex homogenates from enalapril-treated rats displayed a 46% increase in nitric oxide synthase (NOS) activity compared with those from untreated animals. Enalapril treatment did not affect the abundances of NHE3 and V-H(+)ATPase in BBMV. Our results suggest that PCT acidification is increased during chronic ACEi probably due to an increase in NO. synthesis, which would stimulate Na(+)/H(+) exchange and electrogenic proton transport.

Relative contribution of V-H+ATPase and NA+/H+ exchanger to bicarbonate reabsorption in proximal convoluted tubules of old rats.

With aging, the kidney develops a progressive deterioration of several structures and functions. Proximal tubular acidification is impaired in old rats with a decrease in the activity of brush border Na+/H+ exchange and a fall of H-ion flux measured with micropuncture experiments. In the present work we evaluate the contribution of 5-N-ethyl-n-isopropyl amiloride- (EIPA) and bafilomycin-sensitive bicarbonate flux (JHCO3-) in proximal convoluted tubules of young and aged rats. We performed micropuncture experiments inhibiting the Na+/H+ exchanger with EIPA (10(-4) M) and the V-H+ATPase with bafilomycin (10(-6) M). We used antibodies against the NHE3 isoform of the Na+/H+ exchanger and the subunit E of the V-H+ATPase for detecting by Western blot the abundance of these proteins in brush border membrane vesicles from proximal convoluted tubules of young and old rats. The abundance of NHE3 and the V-H+ATPase was similar in 18-month-old and 3-month-old rats. The bicarbonate flux in old rats was 30% lower than in young rats. EIPA reduced by 60% and bafilomycin by 30% in young rats; in contrast, EIPA reduced by approximately 40% and bafilomycin by approximately 50% in old rats. The inhibited by bafilomycin was the same in young and old rats: 0.62 nmol.cm-2.s-1 and 0.71 nmol.cm-2.s-1, respectively. However, the EIPA-sensitive fraction was larger in young than in old rats: 1.26 nmol.cm-2.s-1 vs. 0.85 nmol.cm-2.s-1, respectively. These results suggest that the component more affected in bicarbonate reabsorption of proximal convoluted tubules from aged rats is the Na+-H+ exchanger, probably a NHE isoform different from NHE3.

Altered renal elimination of organic anions in rats with chronic renal failure.

The progress of chronic renal failure (CRF) is characterized by the development of glomerular and tubular lesions. However, little is known about the expression of organic anions renal transporters. The objective of this work was to study, in rats with experimental CRF (5/6 nephrectomy), the expression of the organic anion transporter 1 (OAT1) and organic anion transporter 3 (OAT3) and their contribution to the pharmacokinetics and renal excretion of p-aminohippurate (PAH). Two groups of animals were used: Sham and CRF. Six months after surgery, systolic blood pressure and plasma creatinine concentrations were significantly higher in CRF groups. CRF rats showed a diminution in: the filtered, secreted and excreted load of PAH; the systemic clearance of PAH; the renal OAT1 expression; and the renal Na-K-ATPase activity. No remarkable modifications were observed in the OAT3 expression from CRF kidneys. The diminution in the systemic depuration and renal excretion of PAH may be explained by the decrease in its filtered and secreted load. The lower OAT1 expression in remnant renal mass of CRF rats or/and the lower activity of Na-K-ATPase might justify, at least in part, the diminished secreted load of this organic anion.