Improved histoarchitectural changes with angiotensin receptor blockers in early testicular and cauda toxicity in rats / Mejora de los cambios en la histoarquitectura con bloqueadores de receptores de angiotensina en la toxicidad precoz testicular y de cauda en ratas

SUMMARY: Reproductive dysfunction is a complication for many diseases and toxins. Its early diagnosis and treatment are immensely important. Here the morphological histoarchitecture changes in early testicular and cauda toxicity before and after treatment with angiotensin receptor blockers were evaluated. Low-grade testicular damage was induced using thioacetamide (TAA, 50 mg/kg/day) intraperitoneally for two weeks in rats. The rats were randomly divided into four groups (n = 8) treated daily orally for three weeks as follows: Normal control (distilled water), TAA (positive control), TAA+candesartan (0.2 mg/kg) and TAA+losartan (7.5 mg/kg). Serum testosterone and testicular malondialdehyde and glutathione were measured. The changes in histoarchitecture of testis and cauda epididymis were evaluated by hematoxylin and eosin for general structure, Masson's trichrome for collagen, periodic acid Schiff for basement membrane, and caspase-3 and proliferating cell nuclear antigen (PCNA) for immunohistochemical analysis. The TAA-rats showed decreases of serum testosterone and testicular glutathione, increases in testicular malondialdehyde, degenerative changes and apoptosis in germ cells, thickening of tubular basal lamina and increases in expression of caspase 3, and decreases in expression of PCNA. The ARBs (candesartan and losartan) significantly reversed these changes with non-significant differences in-between. Treatment with ARBs (candesartan and losartan) significantly reversed TAA-induced low-grade testicular and cauda toxicity in rats. This could be potentially useful for early treatment of male patients with occupational toxicant-induced reproductive dysfunction especially if they are using ARBs for other comorbidities.

RESUMEN: La disfunción reproductiva es una complicación por muchas enfermedades y toxinas. Su diagnóstico y tratamiento tempranos son inmensamente importantes. Aquí se evaluaron los cambios morfológicos en la histoarquitectura en la toxicidad precoz testicular y cauda antes y después del tratamiento con bloqueadores de receptores de angiotensina. Se indujo daño testicular de bajo grado usando tioacetamida (TAA, 50 mg / kg / día) por vía intraperitoneal durante dos semanas en ratas. Las ratas se dividieron aleatoriamente en cuatro grupos (n = 8) tratados diariamente por vía oral durante tres semanas de la siguiente manera: control normal (agua destilada), TAA (control positivo), TAA + candesartan (0,2 mg / kg) y TAA + losartán (7,5 mg / kg). Se midieron la testosterona sérica, el malondialdehído testicular y el glutatión. Los cambios en la histoarquitectura de los testículos y la epidermis de la cauda se evaluaron mediante Hematoxilina y Eosina para determinar la estructura general, con tricrómicro de Masson para el colágeno, ácido periódico de Schiff para la membrana basal y la caspasa-3 y el antígeno nuclear de células proliferantes (PCNA) para análisis inmunohistoquímico. Las ratas TAA mostraron disminución de la testosterona sérica y glutatión testicular, aumentos en el malondialdehído testicular, cambios degenerativos y apoptosis en células germinales, engrosamiento de la lámina basal tubular y aumentos en la expresión de la caspasa 3, y disminución en la expresión de PCNA. Los ARB (candesartán y losartán) revirtieron significativamente estos cambios con diferencias no significativas en el medio. El tratamiento con BRA (candesartán y losartán) revirtió significativamente la toxicidad testicular y cauda inducida por TAA en ratas. Esto podría ser potencialmente útil para el tratamiento temprano de pacientes con disfunción reproductiva inducida por tóxicos ocupacionales, especialmente si están usando BRA para otras comorbilidades.

Un novedoso agente en el tratamiento de la insuficiencia cardiaca con función sistólica deprimida / A novel agent in the treatment of heart failure with depressed systolic function

Resumen Introducción: Se revisará la evolución del tratamiento farmacológico de la insuficiencia cardiaca (IC) en los últimos 25 an˜os, desde el concepto de tratamiento con vasodilatadores, pasando por el bloqueo o inhibición del sistema renina-angiotensina-aldosterona y la inhibición betaadrenérgica y su importante contribución en la disminución de la morbimortalidad por IC, el papel de los péptidos natriuréticos y, finalmente, se conocerá uno de los estudios más importantes en el área cardiológica y específicamente en el manejo de la IC, en el cual se demuestra un enfoque modulador de los sistemas neuro humorales que se activan en estos pacientes. Objetivos: La IC constituye la etapa final de la mayoría de las enfermedades cardiovasculares, con una alta tasa de hospitalización y de morbimortalidad cardiovascular, siendo, por lo tanto, de interés constante la necesidad de encontrar un agente terapéutico innovador que disminuya significativamente estas complicaciones y también que mejore la calidad de vida de los que la presentan. Metodología: Se realizará una descripción del PARADIGM-HF Clinical Trial, que utilizó un compuesto sacubitrilo/valsartán para el manejo de la IC con un mecanismo modulador diferente del concepto de bloqueador de sistemas deletéreos que se activan cuando un paciente presenta síntomas y signos de IC. Conclusiones: La muerte por causas cardiovasculares u hospitalización por IC (el punto final primario) se produjo en 914 pacientes (21.8%) en el grupo sacubitrilo/valsartán y 1,117 pacientes (26.5%) en el grupo de enalapril (razón de riesgo en el grupo sacubitrilo/valsartán, 0.80; intervalo de confianza (IC) del 95%: 0.73 a 0.87; p < 0.001 (exacta p = 4.0 × 10 - 7)). De los pacientes que recibieron sacubitrilo/valsartán, 537 (12.8%) fueron hospitalizados por IC, en comparación con los 658 pacientes (15.6%) que recibieron enalapril (razón de riesgo, 0.79; IC del 95%, 0.71 a 0.89; p < 0.001). Un total de 711 pacientes (17.0%) en el grupo sacubitrilo/valsartán y 835 pacientes (19.8%) en el grupo de enalapril murió (razón de riesgo de muerte por cualquier causa, 0.84; IC del 95%, 0.76 a la 0.93; p < 0.001).

Abstract Introduction: A review is presented on the evolution of the pharmacological treatment of heart failure (HF) in the last 25 years, from the concept of treatment with vasodilators to the blocking or inhibition of the renin angiotensin aldosterone system. Beta-adrenergic inhibition and its important contribution in the reduction of morbidity and mortality due to HF will be discussed along with the role of the natriuretic peptides. One of the most important studies in the cardiology area, and specifically in the management of HF, is presented, in which an approach is demonstrated of the modulator of the neurohumoral systems that are activated in these patients. Objectives: HF is the final stage of most cardiovascular diseases, and has a high rate of hospital admission, as well as cardiovascular morbidity and mortality. Therefore, there is constant interest in the need to find an innovative therapeutic agent that significantly reduces these complications and that improves the quality of life of those who suffer from it. Methods: A description will be presented of the PARADIGM-HF Clinical Trial using a sacubitril/valsartán compound for the management of HF with a modulating mechanism different from the concept of a deleterious system blocker that is activated when a patient has symptoms and signs of heart failure. Conclusions: Death due to cardiovascular causes, or hospital admission due to heart failure (the primary endpoint) occurred in 914 patients (21.8%) in the Sacubitril / valsartán group, and 1117 patients (26.5%) in the enalapril group (risk ratio in the sacubitril / valsartán group, 0.80, with a 95% confidence interval [CI]: 0.73 to 0.87, P<0.001 ;exact P= 4.0 × 10 --7;). Of the patients receiving sacubitril / valsartán, 537 (12.8%) were hospitalised due to heart failure, compared with 658 patients (15.6%) receiving enalapril (hazard ratio 0.79, 95% CI: 0.71 to 0.89, P<.001). A total of 711 patients (17.0%) in the sacubitril / valsartán group, and 835 patients (19.8%) in the enalapril group, died (all-cause death rate, 0.84, 95% CI: 0.76 to 0.93, P<.001)

Effect of cilostazol in experimental model of degloving injuries in rat limbs

Abstract Purpose: To evaluate the effect of the cilostazol on the evolution of partially avulsed flaps, using experimental model of cutaneous degloving in rat limbs. Methods: A controlled and randomized experimental study was carried out in which the blood flow and the percentage of flap necrosis were evaluated. We compared the study group, which received cilostazol, and the control group, which received enteral saline solution in the postoperative period. The blood flow in the flap was evaluated through Laser Doppler flowmetry, and a planimetry using the IMAGE J® software was employed for the calculation of the area of necrosis. Results: Enteral administration of cilostazol was associated with a higher mean blood flow in all regions of the flap, with a statistically significant difference in the proximal and middle regions (p<0.001) and a lower percentage of necrotic area in the flap (p<0.001). Conclusion: Postoperative enteral administration of cilostazol increased blood flow and decreased the total area of necrosis of avulsed cutaneous flaps of rat limbs.

Urinary cytokine profiles according to the site of blockade of the renin-angiotensin system in nephrectomized rats / Perfil de citocinas urinárias de acordo com o local de bloqueio do sistema renina angiotensina em ratos nefrectomizados

Abstract Introduction: It is still unknown how the pharmacological inhibition of the Renin Angiotensin System (RAS) impacts the levels of inflammation and fibrosis biomarkers. Objective: This study sought to evaluate the effect of enalapril, candesartan and aliskiren on urinary levels of cytokines in a model of chronic kidney disease (CKD). Methods: Male Wistar rats were submitted to surgical removal of ¾ of renal parenchyma to induce CKD (¾ nephrectomy), or subjected to sham surgery (control). Animals were then randomized into five groups: Sham surgery receiving vehicle; ¾ Nephrectomy receiving vehicle; ¾ Nephrectomy receiving enalapril (10 mg/kg); ¾ Nephrectomy receiving candesartan (10 mg/kg) and ¾ Nephrectomy receiving aliskiren (10 mg/kg). Urine output, water intake, mean arterial pressure (MAP) and urinary concentrations of creatinine, urea, albuminuria, Na+, K+, interleukin (IL) -1β, IL-6, IL-10 and transforming growth factor beta (TGF-β) were measured. Results: Nephrectomy significantly impaired renal function, increased MAP and altered the levels of all evaluated cytokines in urine. Enalapril, candesartan and aliskiren improved renal function and decreased MAP and IL-6 when compared to vehicle-treated nephrectomized group. Candesartan and aliskiren decreased IL-1β, while only candesartan reduced TGF-β and only aliskiren increased IL-10. Conclusion: Enalapril, candesartan and aliskiren presented similar effects on improving renal function and reducing MAP and urinary levels of IL-6 in rats with CKD. On the other hand, cytokine profile differed according to the treatment, suggesting that differential mechanisms were triggered in response to the site of RAS blockade.

Resumo Introdução: Ainda não se sabe como a inibição farmacológica do Sistema Renina Angiotensina (SRA) afeta os níveis de biomarcadores de inflamação e fibrose. Objetivo: Este estudo pretendeu avaliar o efeito de enalapril, candesartan e alisquireno sobre os níveis urinários de citocinas em um modelo de doença renal crônica (DRC). Métodos: Ratos Wistar machos foram submetidos à remoção cirúrgica de ¾ do parênquima renal para induzir DRC (nefrectomia), ou submetidos à cirurgia fictícia (controle). Animais foram então randomizados em cinco grupos: Cirurgia fictícia recebendo veículo; Nefrectomia recebendo veículo; Nefrectomia recebendo enalapril (10 mg/kg); Nefrectomia recebendo candesartan (10 mg/kg) e Nefrectomia recebendo alisquireno (10 mg/kg). Débito urinário, ingesta hídrica, pressão arterial media (PAM) e concentrações urinárias de creatinina, ureia, albumina, Na+, K+, interleucina (IL) -1β, IL-6, IL-10 e fator de transformação e crescimento beta (TGF-β) foram medidas. Resultados: A nefrectomia comprometeu significativamente a função renal, aumentou a PAM e alterou os níveis de todas as citocinas avaliadas na urina. Enalapril, candesartan e alisquireno melhoraram a função renal e diminuíram a PAM e a IL-6 quando comparado aos grupo de animais nefrectomizados tratados com veículo. Candesartan e alisquireno reduziram IL-1β, enquanto somente candesartan diminuiu o TGF-β e somente alisquireno aumentou a IL-10. Conclusão: Enalapril, candesartan e alisquireno apresentaram efeitos similares em relação à melhora da função renal e redução da PAM e dos níveis urinários de IL-6 em ratos com DRC. Por outro lado, o perfil de citocinas diferiu de acordo com o tratamento, sugerindo que diferentes mecanismos sejam desencadeados em resposta ao local de bloqueio do SRA.

Candesartan, rather than losartan, improves motor dysfunction in thioacetamide-induced chronic liver failure in rats

Minimal hepatic encephalopathy is more common than the acute syndrome. Losartan, the first angiotensin-II receptor blocker (ARB), and candesartan, another widely-used ARB, have protected against developing fibrogenesis, but there is no clear data about their curative antifibrotic effects. The current study was designed to examine their effects in an already-established model of hepatic fibrosis and also their effects on the associated motor dysfunction. Low-grade chronic liver failure (CLF) was induced in 3-month old Sprague-Dawley male rats using thioacetamide (TAA, 50 mg·kg−1·day−1) intraperitoneally for 2 weeks. The TAA-CLF rats were randomly divided into five groups (n=8) treated orally for 14 days (mg·kg−1·day−1) as follows: TAA (distilled water), losartan (5 and 10 mg/kg), and candesartan (0.1 and 0.3 mg/kg). Rats were tested for rotarod and open-field tests. Serum and hepatic biochemical markers, and hepatic histopathological changes were evaluated by H&E and Masson's staining. The TAA-CLF rats showed significant increases of hepatic malondialdehyde, hepatic expression of tumor necrosis factor-α (TNF-α), and serum ammonia, alanine aminotransferase, γ-glutamyl transferase, TNF-α, and malondialdehyde levels as well as significant decreases of hepatic and serum glutathione levels. All treatments significantly reversed these changes. The histopathological changes were moderate in losartan-5 and candesartan-0.1 groups and mild in losartan-10 and candesartan-0.3 groups. Only candesartan significantly improved TAA-induced motor dysfunction. In conclusion, therapeutic antifibrotic effects of losartan and candesartan in thioacetamide-induced hepatic fibrosis in rats are possibly through angiotensin-II receptor blocking, antioxidant, and anti-inflammatory activities. Improved motor dysfunction by candesartan could be attributed to better brain penetration and slower "off-rate" from angiotensin-II receptors. Clinical trials are recommended.

Allium sativum compared to cilostazol as an inhibitor of myointimal hyperplasia

Abstract Objective: Intimal hyperplasia is associated with graft failure and vascular sutures in the first year after surgery and in postangioplasty restenosis. Allium sativum (common garlic) lowers cholesterol and has antioxidant effects; it also has antiplatelet and antitumor properties and, therefore, has great potential to reduce or inhibit intimal hyperplasia of the arteries. Our objective is to determine if the garlic has an efficacy to inhibit myointimal hyperplasia compared to cilostazol. Methods: Female New Zealand rabbits were divided into the following groups (n=10 each) according to treatment: group A, garlic, 800 µg×kg-1×day-1, orally; group C, cilostazol, 50 mg.day-1, orally; group PS, 10 ml of 0.9% physiological saline solution, orally. Our primary is the difference of the mean of myointimal hyperplasia. Statistical analysis was performed by using ANOVA and Tukey tests, as well as the Chi-square test. We calculated the 95% confidence interval for each point estimate, and the P value was set as < 0.05. Results: Group PS had a mean hyperplasia rate of 35.74% (95% CI, 31.76–39.71%); group C, 16.21% (95% CI, 13.36–19.05%); and group A, 21.12% (95% CI, 17.26–25.01%); P<0.0001. Conclusion: We conclude that Allium sativum had the same efficacy in inhibiting myointimal hyperplasia when compared to the positive control, cilostazol.

Olmesartan restores the protective effect of remote ischemic perconditioning against myocardial ischemia/reperfusion injury in spontaneously hypertensive rats

OBJECTIVES: Remote ischemic perconditioning is the newest technique used to lessen ischemia/reperfusion injury. However, its effect in hypertensive animals has not been investigated. This study aimed to examine the effect of remote ischemic perconditioning in spontaneously hypertensive rats and determine whether chronic treatment with Olmesartan could influence the effect of remote ischemic perconditioning. METHODS: Sixty rats were randomly divided into six groups: vehicle-sham, vehicle-ischemia/reperfusion injury, vehicle-remote ischemic perconditioning, olmesartan-sham, olmesartan-ischemia/reperfusion and olmesartan-remote ischemic perconditioning. The left ventricular mass index, creatine kinase concentration, infarct size, arrhythmia scores, HIF-1α mRNA expression, miR-21 expression and miR-210 expression were measured. RESULTS: Olmesartan significantly reduced the left ventricular mass index, decreased the creatine kinase concentration, limited the infarct size and reduced the arrhythmia score. The infarct size, creatine kinase concentration and arrhythmia score during reperfusion were similar for the vehicle-ischemia/reperfusion group and vehicle-remote ischemic perconditioning group. However, these values were significantly decreased in the olmesartan-remote ischemic perconditioning group compared to the olmesartan-ischemia/reperfusion injury group. HIF-1α, miR-21 and miR-210 expression were markedly down-regulated in the Olmesartan-sham group compared to the vehicle-sham group and significantly up-regulated in the olmesartan-remote ischemic perconditioning group compared to the olmesartan-ischemia/reperfusion injury group. CONCLUSION: The results indicate that (1) the protective effect of remote ischemic perconditioning is lost in vehicle-treated rats and that chronic treatment with Olmesartan restores the protective effect of remote ischemic perconditioning; (2) chronic treatment with Olmesartan down-regulates HIF-1α, ...

Chikungunya: un reto para los servicios de salud de la República Dominicana / Chikungunya: a challenge for the Dominican Republic's health services

Desde diciembre de 2013, la Región de las Américas se enfrenta por primera vez a una epidemia de chikungunya. Los casos iniciales se registraron en el Caribe francés y, debido al comercio y la movilización de personas, esta epidemia no tardó en llegar a la República Dominicana, cuya población es de 10 millones de habitantes y comparte con Haití la isla La Española. En este artículo se difunde información extraída de diversos artículos y documentos oficiales sobre el virus, la infección y la epidemia de chikungunya, que han sido de gran ayuda para orientar la respuesta en la República Dominicana y pueden ser útiles para mejorar tanto el conocimiento como las actuaciones frente a la epidemia de los trabajadores del sector salud de la Región. Se destaca la importancia que revisten las investigaciones realizadas en países y territorios afectados del océano Índico, como la isla de Reunión, durante la epidemia declarada entre 2005 y 2007, cuando se registró una tasa de ataque mayor de 30%, se identificaron los grupos de riesgo, las formas graves y atípicas de la infección, la transmisión vertical del virus, las formas crónicas, que pueden provocar dolores recurrentes durante tres años, y las defunciones directa o indirectamente relacionadas con el virus chikungunya. Por su alta tasa de ataque, el virus chikungunya se convierte en un reto sin precedentes para los ministerios de salud, que exige una adecuada organización de los servicios de salud, la priorización de la atención a los grupos de riesgo y a los pacientes con formas graves de la enfermedad, así como una adecuada comunicación social y respuesta intersectorial.

The Region of the Americas has been affected since December 2013 by a chikungunya epidemic for the first time. Although the first cases were recorded in the French Caribbean, the epidemic quickly spread to the Dominican Republic due to trade and people movements. The Dominican Republic, which shares the island of Hispaniola with Haiti, has a population of 10 million. This article contains information from a range of different publications and official documents about the chikungunya virus infection and epidemic. These papers were extremely helpful for guiding the response to the epidemic in the Dominican Republic and may also be useful for enhancing knowledge of the virus and responses among health workers elsewhere in the region. Particular attention is drawn to the important research undertaken in countries and territories affected by the epidemic in the Indian Ocean area. This is the case, for example, of the island of La Réunion, where the epidemic had an attack rate of more than 30% between 2005 and 2007. Researchers were able to identify risk groups, severe and atypical forms of the infection, cases of vertical transmission, chronic disease causing recurrent pain over three years, and directly- or indirectly-related deaths from the virus. Given its high attack rate, the chikungunya virus has emerged as an exceptional challenge for health ministries and calls for appropriate organized responses from the health services, prioritization of care for risk groups and patients exhibiting severe forms of the disease, and effective social communication and intersectoral actions.

Effect of candesartan on the expression of sclera-choroidal intercellular adhesion molecule-1 in hypercholesterolemic models

OBJECTIVE: To evaluate the effect of blocking the angiotensin II AT-1 receptor by the systemic administration of candesartan on the expression of intercellular adhesion molecule-1 in the sclera and choroid of hypercholesterolemic rabbits. METHODS: New Zealand rabbits were divided into 3 groups, as follows: GI, which was fed a rabbit standard diet; GII, which was fed a hypercholesterolemic diet; and GIII, which received hypercholesterolemic diet plus candesartan. Samples of the rabbits' sclera and choroid were then studied by hematoxylin-eosin staining and histomorphometric and immunohistochemical analyses for intercellular adhesion molecule-1 expression. RESULTS: Histological analysis of hematoxylin- and eosin-stained sclera and choroid revealed that macrophages were rarely present in GI, and GII had significantly increased macrophage numbers compared to GIII. Moreover, in GII, the sclera and choroid morphometry showed a significant increase in thickness in comparison to GI and GIII. GIII presented a significant increase in thickness in relation to GI. Sclera and choroid immunohistochemical analysis for intercellular adhesion molecule-1 expression revealed a significant increase in immunoreactivity in GII in relation to GI and GIII. GIII showed a significant increase in immunoreactivity in relation to GI. CONCLUSION: Candesartan reduced the expression of intercellular adhesion molecule-1 and consequently macrophage accumulation in the sclera and choroid of hypercholesterolemic rabbits. .

Cilostazol inhibits insulin-stimulated expression of sterol regulatory binding protein-1c via inhibition of LXR and Sp1

Hepatic steatosis is common in obese individuals with hyperinsulinemia and is an important hepatic manifestation of metabolic syndrome. Sterol regulatory binding protein-1c (SREBP-1c) is a master regulator of lipogenic gene expression in the liver. Hyperinsulinemia induces transcription of SREBP-1c via activation of liver X receptor (LXR) and specificity protein 1 (Sp1). Cilostazol is an antiplatelet agent that prevents atherosclerosis and decreases serum triglyceride levels. However, little is known about the effects of cilostazol on hepatic lipogenesis. Here, we examined the role of cilostazol in the regulation of SREBP-1c transcription in the liver. The effects of cilostazol on the expression of SREBP-1c and its target genes in response to insulin or an LXR agonist (T0901317) were examined using real-time RT-PCR and western blot analysis on cultured hepatocytes. To investigate the effect of cilostazol on SREBP-1c at the transcriptional level, transient transfection reporter assays and electrophoretic mobility shift assays (EMSAs) were performed. Cilostazol inhibited insulin-induced and LXR-agonist-induced expression of SREBP-1c and its downstream targets, acetyl-CoA carboxylase and fatty acid synthase, in cultured hepatocytes. Cilostazol also inhibited activation of the SREBP-1c promoter by insulin, T0901317 and Sp1 in a luciferase reporter assay. EMSA analysis showed that cilostazol inhibits SREBP-1c expression by repressing the binding of LXR and Sp1 to the promoter region. These results indicate that cilostazol inhibits insulin-induced hepatic SREBP-1c expression via the inhibition of LXR and Sp1 activity and that cilostazol is a negative regulator of hepatic lipogenesis.

Effects of ischemic preconditioning and cilostazol on muscle ischemia-reperfusion injury in rats

PURPOSE: To evaluate effects of ischemic preconditioning and Cilostazol on muscle ischemia-reperfusion injury. METHODS: Male Wistar rats were submitted to muscle ischemic and reperfusion injury (4h of the left common iliac artery occlusion followed by 1h of reperfusion). Five experimental groups were constituted: Control group (n=4); Ischemia-Reperfusion (IR, n=5); Ischemic preconditioning group (IP, n=6); Ischemia-Reperfusion group treated with cilostazol (IRCi, n=6) and Ischemic preconditioning group treated with cilostazol (IPCi, n=6). At the end, left gracile muscle was removed and embedded in paraffin. Histopathology, neutrophil infiltration, myocyte necrosis and edema were analyzed. RESULTS: When compared with the control group, IR group showed increased neutrophil infiltration, severe necrosis and edema. There was significant difference between myocytes necrosis of IR group and IP group. There was no difference between the histopathological changes between IP, IRCi and IPCi groups. CONCLUSIONS: The model of IR caused severe muscle injury in the rat hind limb and ischemic preconditioning has a protective effect, reducing myocyte necrosis, however, treatment with cilostazol and also the association between cilostazol and preconditioning has no protective effect on the skeletal muscle subjected to ischemia and reperfusion injury. .

Biochemical study of the effects of cilostazol in rats subjected to acute ischemia and reperfusion of hind limbs

PURPOSE: To investigate whether cilostazol has a protective effect on acute ischemia and reperfusion of hind limbs of rats through study of biochemical variables in blood and urine. METHODS: Forty six animals were randomized and divided into two groups. Group I received a solution of cilostazol (10 mg/Kg) and group II received saline solution 0.9% (SS) by orogastric tube after ligature of the abdominal aorta. After four hours of ischemia the animals were divided into four subgroups: group IA (Cilostazol): two hours of reperfusion. Group IIA (SS): two hours of reperfusion. Group IB (Cilostazol): six hours of reperfusion. Group IIB (SS) six hours of reperfusion. After the reperfusion period, was held to collect urine and blood for biochemical measurements. The biochemical parameters studied were: urea, creatinine, sodium, potassium and myoglobin in blood and urea, creatinine, myoglobin in urine. RESULTS: There was no statistically significant difference between groups. CONCLUSION: Cilostazol had no protective effect on ischemic acute reperfusion of hind limbs of rats in this model.

Effects of cilostazol in kidney and skeletal striated muscle of Wistar rats submitted to acute ischemia and reperfusion of hind limbs / Efeitos do cilostazol em rim e musculatura estriada esquelética de ratos Wistar submetidos à isquemia aguda e reperfusão de membros posteriores

PURPOSE: To investigate the effect of cilostazol, in kidney and skeletal muscle of rats submitted to acute ischemia and reperfusion. METHODS: Fourty three animals were randomized and divided into two groups. Group I received a solution of cilostazol (10 mg/Kg) and group II received saline solution 0.9% (SS) by orogastric tube after ligature of the abdominal aorta. After four hours of ischemia the animals were divided into four subgroups: group IA (Cilostazol): two hours of reperfusion. Group IIA (SS): two hours of reperfusion. Group IB (Cilostazol): six hours of reperfusion. Group IIB (SS) six hours of reperfusion. After reperfusion, a left nephrectomy was performed and removal of the muscles of the hind limb. The histological parameters were studied. In kidney cylinders of myoglobin, vacuolar degeneration and acute tubular necrosis. In muscle interstitial edema, inflammatory infiltrate, hypereosinophilia fiber, cariopicnose and necrosis. Apoptosis was assessed by immunohistochemistry for cleaved caspase-3 and TUNEL. RESULTS: There was no statistically significant difference between groups. CONCLUSION: Cilostazol had no protective effect on the kidney and the skeletal striated muscle in rats submitted to acute ischemia and reperfusion in this model.

OBJETIVO: Investigar o efeito do cilostazol no rim e na musculatura esquelética de ratos submetidos à isquemia aguda e reperfusão. MÉTODOS: Quarenta e três animais foram aleatoriamente distribuídos em dois grupos. Grupo I recebeu solução de cilostazol (10 mg/Kg) e Grupo II recebeu solução fisiológica a 0,9% (SF), após ligadura da aorta abdominal. Decorridas quatro horas de isquemia os animais foram distribuídos em quatro subgrupos: Grupo IA (Cilostazol): duas horas de reperfusão. Grupo IIA (SF): duas horas de reperfusão. Grupo IB (Cilostazol): seis horas de reperfusão. Grupo IIB (SF): seis horas de reperfusão. Após a reperfusão, realizou-se nefrectomia esquerda e a retirada da musculatura de membro posterior. Os parâmetros histológicos estudados em rim foram cilindros de mioglobina, degeneração vacuolar e necrose tubular. Em músculo foram edema, infiltrado inflamatório, hipereosinofilia de fibras, cariopicnose e necrose. A apoptose foi avaliada por imunohistoquímica, através da caspase-3 clivada e TUNEL. RESULTADOS: Não houve diferença estatisticamente significante entre os grupos estudados. CONCLUSÃO: O cilostazol não teve efeito protetor sobre o rim e sobre a musculatura estriada esquelética em ratos Wistar submetidos à isquemia aguda e reperfusão no modelo estudado.

KR-31543 reduces the production of proinflammatory molecules in human endothelial cells and monocytes and attenuates atherosclerosis in mouse model

KR-31543, (2S, 3R, 4S)-6-amino-4-[N-(4-chlorophenyl)-N-(2-methyl-2H-tetrazol-5-ylmethyl) amino]-3,4-dihydro-2-dimethyoxymethyl-3-hydroxy-2-methyl-2H-1-benz opyran is a new neuroprotective agent for ischemia-reperfusion damage. It has also been reported that KR-31543 has protective effects on lipid peroxidation and H2O2-induced reactive oxygen species production. In this study, we investigated the anti-inflammatory and anti-atherogenic properties of KR-31543. We observed that KR-31543 treatment reduced the production of MCP-1, IL-8, and VCAM-1 in HUVECs, and of MCP-1 and IL-6 in THP-1 human monocytes. We also examined the effect of KR-31543 on monocytes migration in vitro. KR-31543 treatment effectively reduced the migration of THP-1 human monocytes to the HUVEC monolayer in a dose-dependent manner. We next examined the effects of this compound on atherogenesis in LDL receptor deficient (Ldlr-/-) mice. After 10 weeks of western diet, the formation of atherosclerotic lesion in aorta was reduced in the KR-31543-treated group compared to the control group. The accumulation of macrophages in lesion was also reduced in KR-31543 treated group. However, the plasma levels of total cholesterol, HDL, LDL, and triglyceride were not affected by KR-31543 treatment. Taken together, these results show that KR-31543 has anti-inflammatory properties on human monocytes and endothelial cells, and inhibits fatty streak lesion formation in mouse model of atherosclerosis, suggesting the potential of KR-31543 for the treatment for atherosclerosis.

Up-regulation of BLT2 is critical for the survival of bladder cancer cells

The incidence rates of urinary bladder cancer continue to rise yearly, and thus new therapeutic approaches and early diagnostic markers for bladder cancer are urgently needed. Thus, identifying the key mediators and molecular mechanisms responsible for the survival of bladder cancer has valuable implications for the development of therapy. In this study, the role of BLT2, a receptor for leukotriene B4 (LTB4) and 12(S)-hydroxyeicosatetraenoic acid (HETE), in the survival of bladder cancer 253J-BV cells was investigated. We found that the expression of BLT2 is highly elevated in bladder cancer cells. Also, we observed that blockade of BLT2 with an antagonist or BLT2 siRNA resulted in cell cycle arrest and apoptotic cell death, suggesting a role of BLT2 in the survival of human bladder cancer 253J-BV cells. Further experiments aimed at elucidating the mechanism by which BLT2 mediates survival revealed that enhanced level of reactive oxygen species (ROS) are generated via a BLT2-dependent up-regulation of NADPH oxidase members NOX1 and NOX4. Additionally, we observed that inhibition of ROS generation by either NOX1/4 siRNAs or treatment with an ROS-scavenging agent results in apoptotic cell death in 253J-BV bladder cancer cells. These results demonstrated that a 'BLT2-NOX1/4-ROS' cascade plays a role in the survival of this aggressive bladder cancer cells, thus pointing to BLT2 as a potential target for anti-bladder cancer therapy.

Cilostazol Protects Endothelial Cells Against Lipopolysaccharide-Induced Apoptosis Through ERK1/2- and P38 MAPK-Dependent Pathways

BACKGROUND/AIMS: We examined the effects of cilostazol on mitogen-activated protein kinase (MAPK) activity and its relationship with cilostazol-mediated protection against apoptosis in lipopolysaccharide (LPS)-treated endothelial cells. METHODS: Human umbilical vein endothelial cells (HUVECs) were exposed to LPS and cilostazol with and without specific inhibitors of MAPKs; changes in MAPK activity in association with cell viability and apoptotic signaling were investigated. RESULTS: Cilostazol protected HUVECs against LPS-induced apoptosis by suppressing the mitochondrial permeability transition, cytosolic release of cytochrome c, and subsequent activation of caspases, stimulating extracellullar signal-regulated kinase (ERK1/2) and p38 MAPK signaling, and increasing phosphorylated cAMPresponsive element-binding protein (CREB) and Bcl-2 expression, while suppressing Bax expression. These cilostazol-mediated cellular events were effectively blocked by MAPK/ERK kinase (MEK1/2) and p38 MAPK inhibitors. CONCLUSIONS: Cilostazol protects HUVECs against LPS-induced apoptosis by suppressing mitochondriadependent apoptotic signaling. Activation of ERK1/2 and p38 MAPKs, and subsequent stimulation of CREB phosphorylation and Bcl-2 expression, may be responsible for the cellular signaling mechanism of cilostazolmediated protection.

Effects of metronidazole, tinidazole, captopril and valsartan on taste and serum levels of zinc and magnesium

To study the effect of metronidazole, tinidazole, captopril and valsartan on the levels of zinc and magnesium in the serum of rabbits and humans and the histology of taste buds in rabbits. We conducted this study in the College of Medicine and Teaching Hospital, Basrah, Iraq from April 2005 to September 2006. It was in 2 parts: a clinical observational study of 54 patients treated with one of these drugs. The second part involved oral administration of metronidazole [45mg/kg], tinidazole [40mg/kg], captopril [3mg/kg] or valsartan [3mg/kg] or normal saline to 42 rabbits randomly. Serum zinc and magnesium were measured, and histological sections of tongues were examined for taste buds. In rabbits, oral metronidazole [13.6%] or tinidazole [7%] resulted in a significant reduction in serum zinc. Reductions in captopril [6.7%] and valsartan [4.2%] were smaller and insignificant. Body weight increased by 15.5gm [1391 +/- 225.3 gm to 1407 +/- 223.2 gm] in the control group, a lesser increase of approximately 8 gm, was found in the metronidazole group [1452 +/- 222.6 gm to 1460 +/- 221.9 gm]. Rabbit tongues showed moderate degeneration of taste buds caused by tinidazole, severe degeneration of captopril and minimal changes of valsartan. In humans, the drugs did not result in significant changes in serum zinc or magnesium. Approximately 73.3% of patients in the metronidazole group and 11.1% in the valsartan group had taste changes. It is concluded that metronidazole and tinidazole, but not captopril or valsartan resulted in a significant reduction of zinc level in rabbit, but not in human. Captopril and not valsartan caused severe degeneration in taste buds. Serum zinc level seems not to be related to taste buds changes

Short-term effects of irbesartan treatment on microalbuminuria in patients with normotensive type 2 diabetes

A total of 40 normotensive type 2 diabetes patients [mean age 55.1 +/- 11.4 years] who had microalbuminuria were included in this non-comparative and prospective research study. The study took place in Ege University Hospital, Bornova-Izmir, Turkey, between January 2005 and April 2005. Patients were treated with irbesartan 300mg/day for 3 months. Physical examination, medical history, systolic and diastolic blood pressure levels, microalbuminuria, diabetes markers fasting and non-fasting blood glucose, glycosylated hemoglobin [HbA1c], lipid profile, creatinine and urea were obtained at baseline and after 3 months of irbesartan treatment. The primary assessment criterion was the change in microalbuminuria. The mean microalbuminuria level at baseline was 110.8 +/- 93.1mg/24 hours. It significantly decreased to 45.6 +/- 62.5mg/24 hours at the end of 3 months of irbesartan treatment [p < 0.001]. When patients were stratified according to the change in the microalbuminuria status after treatment, 90% of them either returned to normo albuminuria or their microalbuminuria decreased. Both diastolic and systolic blood pressures, fasting and non-fasting blood glucose, and HbA1c were found to be significantly decreased after 3 months of irbesartan treatment compared to pre-treatment values. The positive effect of irbesartan on microalbuminuria occurs independently from HbA1c, fasting blood glucose, and blood pressures. The short-term treatment of irbesartan is effective to decrease microalbuminuria in normotensive type 2 diabetes patients, independent of its antihypertensive effect. There is a need for multicenter prospective studies to investigate this further

Mayor expresión de la enzima convertidora de angiotensina I homóloga (ECA2) en la pared arterial de ratas con niveles genéticamente elevados de angiotensina II: efectos decandesartán y fasudil / Increased expression of homologous Angiotensin I converting enzyme (ACE2) in the arterial wall of rats with genetically elevated levels of Angiotensin II: effects of candesartan and fasudil

El polimorfismo de la enzima convertidora de angiotensina I (ECA) determina mayor actividad de ECA y niveles de angiotensina (Ang) II en ratas Brown Norway (BN) y menor actividad de ECA y niveles de Ang II en ratas Lewis (L). La relación entre ECA, ECA2, la estimulación del receptor de angiotensina (Ang) II y la vía transduccional Rho A/Rho kinasa no ha sido explorada. Objetivo: Determinar la actividad y expresión de ECA2 y eNOS en la aorta de ratas con niveles genéticamente elevados de ECA y Ang II y los efectos independientes de la inhibición del receptor de Ang II (RAT1) y de Rho kinasa (ROCK). Métodos: Se usaron ratas macho homocigotos de 150 grs BN y L. Para inhibir ROCK, se administró fasudil (100 mg/Kg/día por gavage) y para inhibir el RAT1 se administró candesartán (10 mg/kg/día por gavage) a ratas BN, durante 7 días. Se determinó la presión arterial sistólica (PAS), la actividad circulante de ECA y ECA2 por fluorimetría y la expresión génica de ECA2 y de eNOS por RT-PCR (en unidades de densidad óptica).Resultados como promedio(ES). Conclusión: Los mayores niveles de ECA y AngII están asociados a menor actividad circulante de ECA2 en ratas normotensas. Candesartán y fasudil aumentaron la actividad y expresión génica de ECA2 en la pared arterial de ratas BN, efecto que fue mayor al inhibir ROCK. El aumento de ECA2 se asoció a mayor expresión génica de eNOS independientemente de la vía inhibida. Estos resultados permiten plantear que óxido nítrico y ROCK pudieran ser activadores endógenos de ECA2.

Background: Angiotensin I converting enzyme (ACE) polymorphism is associated with increased ACE activity and angiotensin II (A-II) levels in Brown Norway (BN) rats and decreased ACE and A-II levels in Lewis (L) rats. The relationship of ACE, ACE 2, stimulation of A-II receptor and activity of the Rho A/ Rho kinase transductional pathway is not known. Aim: To determine the activity and expression of ACE 2 and eNOS in the aortic wall of rats with genetically elevated leves of ACE and A-II and the independent effects of A-II receptor (ART2) and Rho kinase (ROCK) inhibition. Methods: Homozygous BN and L male rats wighing 150g were used. Fasudil (100mg/kg/day via gavage) was administer to inhibit ROCK and candesartan (10 mg/Kg/day) was given to inhibit ART1, during 7 days. Systolic blood pressure (SBP, ACE and ACE2 circulating activity was measured by fluorimetry. Genetic expression of ACE2 and eNOS was determined by RT-PCR (optical density units). Results are expressed as mean +/- SEM.

Effect of Ramipril, Valsartan, Candesartan and Lacidipine on inflammation and gastric ulcer in rats

The present study investigated and compared the effect of the angiotensin converting enzyme inhibitor ramipril and the angiotensin II receptor blockers valsartan and candesartan and the calcium channel blocker lacidipine on inflammation and gastric ulcer in rats. The acute inflammation was induced by intraplantar injection of carrageenan [1%] in the rat hind paw. Gastric ulcer was evoked by s.c. indomethacin [20 mg/kg]. When given s.c. 30 min prior to induction of inflammation, ramipril [0.23 and 0.45 mg/kg], valsartan [7.5 and 15 mg/kg], candesartan [0.72 and 1.44 gm/kg] failed to reduce paw oedema response. Meanwhile, lacidipine at the lower dose of 0.18 mg/kg displayed mild anti-inflammatory activity up to 1 hr, reducing paw odema by 26.7% for 1 hr post-carrageenan, while a higher dose of 0.36 mg/kg inhibited oedema formation by 33.5, 31, 23.6 and 22.3% at 1, 2, 3 and 4 hr post-carrageenan, respectively. The acute gastric mucosal lesions evoked by indomethacin in the rat were aggravated by co-administration of ramipril 0.23 and 0.45 mg/kg, valsartan 7.5 and 15 mg/kg, lacidipne 0.18 and 0.36 mg/kg and candesartan 0.72 mg/kg, but reduced by candesartan 1.44 mg/kg. Findings in the present study do not favor an anti-inflammatory activity for ramipril, valsartan and candesartan, but indicates an antioedema effect for lacidipine at the doses employed. These agents are likely to adversely affect gastric mucosal integrity and enhance the indomethacin-induced gastric injury