Rosiglitazona e lesão vascular em coelhos hipercolesterolêmicos: avaliação da formação neointimal / Rosiglitazone and vascular injury in hypercholesterolemic rabbits: neointimal formation assessment / Rosiglitazona y lesión vascular en conejos hipercolesterolémicos

FUNDAMENTO: O uso da rosiglitazona tem sido o objeto de extensas discussões. OBJETIVO: Avaliar os efeitos da rosiglitazona nas artérias ilíacas, no local da injúria e na artéria contralateral, de coelhos hipercolesterolêmicos submetidos à lesão por cateter-balão. MÉTODOS: Coelhos brancos machos receberam uma dieta hipercolesterolêmica através de gavagem oral por 6 semanas e foram divididos em 2 grupos: grupo rosiglitazona (GR - 14 coelhos tratados com rosiglitazona por 6 semanas) e grupo controle (GC - 18 coelhos sem rosiglitazona). Os animais foram submetidos a lesão por cateter-balão na artéria ilíaca direita no 14º dia. RESULTADOS: Na artéria ilíaca contralateral, não houve diferença significante na razão entre as áreas intimal e medial (RIM) entre os grupos GR e GC. A rosiglitazona não reduziu a probabilidade de lesões tipo I, II ou III (72,73 por cento vs 92,31 por cento; p=0,30) e lesões tipo IV ou V (27,27 por cento vs 7,69 por cento; p=0,30). Na artéria ilíaca homolateral, a área intimal era significantemente menor no GR quando comparado ao GC (p = 0,024). A área luminal era maior no GR quando comparado ao GC (p < 0,0001). Houve uma redução significante de 65 por cento na IMR no GR quando comparado ao GC (p = 0,021). Nenhum dos critérios histológicos para lesões ateroscleróticas tipos I a V (American Heart Association) foram encontrados na artéria ilíaca homolateral. CONCLUSÃO: Esses achados demonstram que a administração de rosiglitazona por 6 semanas impede a aterogênese no local da lesão, mas não em um vaso distante do sítio da lesão.

BACKGROUND: Rosiglitazone has been the focus of extensive discussion. OBJECTIVE: To evaluate the effects of rosiglitazone on iliac arteries, both at the injury site and the contralateral artery, of hypercholesterolemic rabbits undergoing balloon catheter injury. METHODS: White male rabbits were fed a hypercholesterolemic diet by oral gavage for 6 weeks and divided into two groups as follows: rosiglitazone group (14 rabbits treated with rosiglitazone during 6 weeks) and the control group (18 rabbits without rosiglitazone). Animals underwent balloon catheter injury of the right iliac artery on the 14th day. RESULTS: In the contralateral iliac artery, there was no significant difference in the intima/media layer area ratio (IMR) between the control and rosiglitazone groups. Rosiglitazone did not reduce the probability of type I, II, or III lesions (72.73 percent vs 92.31 percent; p=0.30) and type IV or V lesions (27.27 percent vs 7.69 percent; p=0.30). As for the homolateral iliac artery, the intimal area was significantly lower in the rosiglitazone group, as compared to the control group (p = 0.024). The luminal layer area was higher in the rosiglitazone group vs. the control group (p < 0.0001). There was a significant reduction of 65 percent in the IMR in the rosiglitazone group vs the control group (p = 0.021). None of the histological criteria for type I-V atherosclerotic lesions (American Heart Association) were found in the homolateral iliac artery. CONCLUSION: These findings demonstrate that rosiglitazone given for 6 weeks prevents atherogenesis at the injury site, but not in a vessel distant from the injury site.

FUNDAMENTO: El uso de rosiglitazona ha estado siendo el objeto de extensas discusiones. OBJETIVO: Evaluar los efectos de la rosiglitazona en las arterias ilíacas, en el local de la injuria y en la arteria contralateral, de conejos hipercolesterolémicos sometidos a la lesión por catéter-balón. MÉTODOS: Conejos blancos machos recibieron una dieta hipercolesterolémica a través de gavage oral por 6 semanas y se los dividieron en 2 grupos: grupo rosiglitazona (GR - 14 conejos tratados con rosiglitazona por 6 semanas) y grupo control (GC - 18 conejos sin rosiglitazona). Los animales se sometieron a lesión por catéter-balón en la arteria ilíaca derecha en el 14º día. RESULTADOS: En la arteria ilíaca contralateral, no hubo diferencia significativa en la razón entre las áreas íntima y media (RIM) entre los grupos GR y GC. La rosiglitazona no redujo la probabilidad de lesiones tipo I, II ó III (72,73 por ciento vs 92,31 por ciento; p=0,30) y lesiones tipo IV ó V (27,27 por ciento vs 7,69 por ciento; p=0,30). En la arteria ilíaca homolateral, el área intima era significantemente menor en el GR cuando comparado al GC (p = 0,024). El área luminal era mayor en el GR cuando comparado al GC (p < 0,0001). Hubo una reducción significante del 65 por ciento en la IMR en el GR cuando comparado al GC (p = 0,021). Ningún de los criterios histológicos para lesiones ateroscleróticas tipos I a V (American Heart Association) se encontraron en la arteria ilíaca homolateral. CONCLUSIÓN: Estos hallazgos demuestran que la administración de rosiglitazona por 6 semanas impide la aterogénesis en el local de la lesión, pero no en un vaso distante del sitio de la lesión.

Comparison of metformin, gliclazide MR and rosiglitazone in monotherapy and in combination for type 2 diabetes / Comparação de metformina, gliclazida MR e rosiglitazona em monoterapia e em combinação para o diabetes tipo 2

OBJECTIVE: To compare the efficacy and tolerability of metformin, rosiglitazone and gliclazide MR as monotherapy and in combination in the treatment of type 2 diabetes. SUBJECTS AND METHODS: 250 patients treated with oral antidiabetic agents for at least 24 weeks in monotherapy or in combination therapy were included in this retrospective study. RESULTS: As monotherapy the reduction of fasting plasma glucose (FPG), postprandial glycemia (PPG) and HbA1c was similar with the three drugs after 24 weeks. Among patients on combination therapy, the reduction in HbA1c, FPG and PPG was significantly lower with rosiglitazone plus metformin, as compared to metformin plus gliclazide MR or gliclazide MR plus rosiglitazone. Patients treated with rosiglitazone achieved less favorable changes in lipid profile. CONCLUSION: In monotherapy all drugs were equally effective in improving glycemic control, whereas the combination of metformin plus gliclazide MR provided the best results concerning the improvement of both, glycemic control and lipid profile.

OBJETIVO: Comparar a eficácia e a tolerabilidade da metformina, rosiglitazona e gliclazida MR em monoterapia ou em combinação no tratamento do diabetes tipo 2. SUJEITOS E MÉTODOS: 250 pacientes tratados com antidiabéticos orais por pelo menos 24 semanas, em monoterapia ou em terapia combinada, foram incluídos neste estudo retrospectivo. RESULTADOS: Como monoterapia, a redução da glicemia de jejum (GJ), glicemia pós-prandial (GPP) e HbA1c foi similar com as três drogas, após 24 semanas. Entre os pacientes em terapia combinada, a redução da HbA1c, GJ e GPP foi significativamente menor com rosiglitazona e metformina, em comparação com metformina e gliclazida MR ou gliclazida MR mais rosiglitazona. Os pacientes tratados com rosiglitazona obtiveram mudanças menos favoráveis no perfil lipídico. CONCLUSÃO: Em monoterapia todos os medicamentos foram igualmente eficazes na melhora do controle glicêmico, enquanto a combinação de metformina e gliclazida MR proporcionou os melhores resultados relativos à melhoria de ambos, controle glicêmico e perfil lipídico.

Agonistas PPAR (Rosiglitazona, Bezafibrato e Fenofibrato) e alterações bioquímicas e estruturais em órgãos-alvo de camundongos C57BL/6 alimentados com dieta hiperlipídica rica em sacarose / PPAR agonists (Rosiglitazone, Bezafibrate and Fenofibrate) and biochemical and structural alterations in organs target of C57BL/6 mice fed high-fat high sucrose chow

Este trabalho teve o objetivo de estudar o efeito de medicamentos com diferentes ações agonista PPAR (rosiglitazona, fenofibrato e bezafibrato) sobre o perfil lipídico, glicídico e alterações na massa corporal e morfologia do tecido adiposo e pancreático em modelo de diabetes e sobrepeso induzido por dieta. Camundongos C57BL/6 (2 meses de idade) foram alimentados com dieta padrão (SC, n=10) ou dieta hiperlipídica rica em sacarose (HFHS, n=40) por 6 semanas. Logo após, os animais HFHS foram subdividos em: HFHS não tratado e HFHS tratado com rosiglitazona (HFHS-Ro), fenofibrato (HFHS-Fe) ou bezafibrato (HFHS-BZ) (5 semanas). Os camundongos alimentados com dieta HFHS apresentaram maior glicemia e insulina de jejum (+33% e +138%, respectivamente), intolerância à glicose, resistência à insulina, aumento da massa corporal (MC) (+20%) e adiposidade, hipertrofia de adipócitos e redução da imunocoloração para adiponectina no tecido adiposo. No pâncreas houve aumento da massa (+28%), acúmulo de gordura (+700%), hipertrofia da ilhota (+38%) e redução da imunocoloração para GLUT-2 (-60%). A rosiglitazona diminuiu a glicemia e insulina de jejum, porém induziu o ganho de MC e hipertrofia cardíaca. O fenofibrato estabilizou a MC, enquanto o bezafibrato levou a perda de MC. Apenas o bezafibrato impediu a hipertrofia da ilhota. A imunocoloração para GLUT-2 foi aumentada por todos os medicamentos, e não houve alterações na imunocoloração para o PPARalfa. Sinais morfológicos de pancreatite foram vistos no grupo HFHS-Fe, apesar dos níveis normais de amilase e lipase séricos. A rosiglitazona exacerbou a infiltração intrapancreática de gordura (+75% vs. HFHS), e o bezafibrato aumentou a imunocoloração para o PPARbeta/delta nas ilhotas pancreáticas. Em conclusão, o bezafibrato apresentou um efeito mais amplo sobre as alterações metabólicas, morfológicas e biométricas decorrentes da dieta HFHS, sugerindo que a inibição das três isoformas do PPAR seria melhor do que a inibição...

This work aimed to evaluate the effect of peroxisome proliferator-activated receptor (PPAR) agonists (rosiglitazone, fenofibrate and bezafibrate) on lipid and glucose metabolism, body mass, and adipose and pancreatic tissue morphology in a model of diet-induced type 2 diabetes and overweight in mice. Two-month-old male C57BL/6 mice were fed a standard chow (SC, n=10) or a high-fat high-sucrose chow (HFHS, n=40) for 6 weeks, and then HFHS-fed mice were subdivided by treatment: untreated HFHS and HFHS treated with rosiglitazone (HFHS-Ro), fenofibrate (HFHS-Fe), or bezafibrate (HFHS-Bz) (5 weeks on medication). HFHS-fed mice have altered fasting glucose (+33%) and insulin (+138%), GI, IR, increased body mass (+20%) and fat pad weight, adipocyte hypertrophy, and decreased adiponectin immunostain. They also presented increased pancreatic (+28%) mass, intrapancreatic fat (+700%), islet hypertrophy (+38%), and decreased GLUT-2 immunostain (-60%). Rosiglitazone reduced fasting glucose and insulin but induced weight gain and heart hypertrophy. Fenofibrate impaired body mass gain, while bezafibrate induced weight loss. Only bezafibrate impaired islet hypertrophy. GLUT-2 immunostain was improved by all treatments, and there were no alterations in PPAR-alfa stain. There were morphological signs of pancreatitis in fenofibrate-treated mice, although there was no alteration in serum amylase and lipase. Rosiglitazone exacerbated pancreatic fat infiltration (+75% vs. HFHS group), and bezafibrate increased PPAR-beta expression in pancreatic islets. In conclusion, bezafibrate showed a wider range of action on metabolic, morphologic, and biometric alterations due to HFHS intake, suggesting that inhibiting the three PPAR isoforms is better than inhititing each isoform alone. Rosiglitazone exacerbated body mass gain, pancreatic fat infiltration and induced heart hyperthophy as well, thus, precaution has to be taken in prescribing rosiglitazone to obese patients.

Efecto lipolítico del Resveratrol en células 3T3-L1 / Lipolitic effect of Resveratrol in cells 3T3-L1

Introducción: La obesidad es uno de los mayores factores de riesgo para la resistencia a la insulina y la aparición de la diabetes tipo 2. Las proteínas Sirtruinas, entre ellas la Sirtruina 1 (Sirt 1), tiene la capacidad de inhibir la expresión de los genes controlados por el receptor nuclear PPARy promoviendo la movilización de los ácidos grasos desde el adipocito y evitando su almacenamiento. Objetivo: El propósito de este trabajo es evaluar la capacidad del Resveratrol como agente lipolítico en células adiposas diferenciadas. Materiales y métodos: La adipogénesis se realizó mediante la incubación preadipocitos de ratón de la línea celular 3T3.-L1 en presencia de un cóctel de diferenciación con Rosiglitazona, Isobutil Xantina y Dexametasona, y se llevaron a cabo observaciones cada dos días en el período comprendido entre los 0 y 10 días. Posteriormente, se aplicaron dosis de Rosiglitazona y Resveratrol y se realizaron nuevas observaciones hasta el día 6 para corroborar el efecto del Resveratrol. Resultados y discusión: Los resultados obtenidos nos permitieron observar el efecto lipolítico del Resveratrol sobre las células adiposas dado que la cantidad de triglicéridos dentro de las mismas fue menor con respecto a las células diferenciadas y que no fueron tratadas con éste. Esto puede ser causado por la capacidad del Resveratrol de estimular la actividad de la Sirt 1 que a su vez provoca la inhibición del PPARy. Conclusiones: Estos trabajos nos permitirán en el futuro desarrollar nuevas intervenciones en el tratamiento de la obesidad y sus complicaciones...

Introduction: The obesity it is one of the main risk factor for develop insulin resistance and type 2 diabetes, one component of calorie restriction in mammals it is given by Sirtuins proteins among them (SIRT 1), which have the capacity of inhibit the expression of the genes control by the nuclear receptor PPARy, promoting the mobilization of the fatty acids from the adipocyte and avoiding their storage. Objective: The purpose of this work is to evaluate the capacity of Resveratrol (flavonoid found in grape skin) as a lipolytic agent on adipose cells differentiated by Rosiglitazone. Materials and methods: Fibroblast preadipocyte adipogenesis was carried out using Rosiglitazona, incubating murine 3T3-L1 cells in the presence of a differentiation cocktail of Rosiglitazone, Isobutil Xantine and Dexametasone, monitoring between days 0 to 10 of differentiation every two days. Subsequently doses of Resveratrol and Rosiglitazone were added to each cells culture and followed up until day 6, to make sure the Resveratrol effect. The triglycerides quantification was performed qualitatively by red oil stain and quantitatively by isopropanol extraction and absorbance measurement at 510 nm.Results and analysis: The results allowed us to see the Resveratrol lipolytic effect on the adipocyte cells, because the amount of triglycerides was lower than the cultures differentiated by Rosiglitazone. This could be caused by the Resveratrol capacity of stimulate the SIRT 1 activity, which also inhibit PPARy. Conclusions: This kind of work will help in develop new interventions in the treatment of the obesity and complications...

Efecto de la combinación rosiglitazona/metformin y de la monoterapia con metformin sobre los componentes del síndrome metabólico

Objetivos: Comparar el efecto de la combinación rosiglitazona/metformin con el de metformin como monoterapia, sobre los componentes del síndrome metabólico (SM). Métodos: Se realizó un ensayo clínico, doble ciego, aleatorizado. Se incluyeron 25 pacientes de ambos sexos, entre 20 y 75 años que cumplían con los criterios diagnósticos de la ATP III para SM. Se les registró tensión arterial (TA), talla, peso y circunferencia abdominal (CA). Se calculó el índice de masa corporal (IMC). Se les determinó antes y a los 4 meses del tratamiento glicemia e insulinemia en ayunas y 2 horas post carga y perfil lipídico. Se calculó el índice HOMA. Los pacientes se distribuyeron aleatoriamente en dos grupos: Grupo A, 11 pacientes (10 mujeres y 1 hombre), edad promedio 43,45±14,98 quienes recibieron metformin (500 mg) combinado con rosiglitazona (2 mg) en una tableta dos veces al día; Grupo B, 14 pacientes (13 mujeres y 1 hombre), edad promedio 44,21±10,28 quienes recibieron metformin 850 mg en una tableta dos veces al día. Resultados: Las variables estudiadas no fueron diferentes entre ambos grupos, antes del tratamiento. Con ambos tratamientos, el IMC y la CA disminuyeron significativamente aunque el cambio porcentual fue mayor en el grupo A (IMC: 8,1% versus 3,4%; CA: 9,7% versus 4%; p<0,05). En el grupo A hubo disminución significativa del HOMA y la insulina en ayunas y postcarga. En el grupo B se observó disminución significativa de la TA y de los niveles de insulina en ayunas y postcarga y mejoría no significativa del HOMA. No se observaron cambios significativos en el perfil lipídico. Hubo una correlación positiva de la CA con el HOMA (r=0,618; p=0,0007). Conclusiones: Ambas terapias fueron beneficiosas en el tratamiento de los pacientes con SM, observándose, una mayor reducción de la CA y del HOMA en aquellos que recibieron la combinación rosiglitazona/metformin y una mayor reducción de las cifras tensionales en los que recibieron metformin como monoterapia.

Objective: To compare the effect of the combination rosiglitazone/metformin with the metformin as monotherapy, on the components of the metabolic syndrome (MS). Methods: A double blind, randomized, clinical study was carried out. Twenty five patients of both sexes, between 20 and 75 years of age, with the diagnosis of MS (ATP III criteria) were included. Blood pressure (BP), height, weight and abdominal circumference (AC) were registered. Fasting and 2 hours post load plasma glucose and insulin levels and fasting lipid profile were measured. The body mass index (BMI) and the HOMA index were calculated. The patients were distributed at random in two groups: Group A, 11 patients (10 women and 1 man), average age 43,45±14,98 who received metformin (500 mg) in combination with rosiglitazone (2 mg) in a tablet two times a day; Group B, 14 patients (13 women and 1 man), average age 44,21±10,28 who received metformin 850 mg in a tablet two times a day. Results: The studied variables were not different between both groups, before the treatment. With both treatments, the BMI and the AC diminished significantly though the percentage of change was bigger in the group A (BMI: 8,1 % versus 3,4 %; AC: 9,7 % versus 4 %; p <0,05). There was a significant decrease of the HOMA index and the fasting and post load insulin levels in the group A. In the group B was observed significant decrease of the values of BP and of the fasting and postload insulin levels and a not significant improvement of the HOMA index. Significant changes were not observed in the lipid profile. There was a positive correlation of the AC with the HOMA index (r=0,618; p=0,0007). Conclusions: Both therapies were beneficial in the treatment of the patients with MS. A major reduction of the AC and of the HOMA index in those who received the combination rosiglitazone/metformin and a major reduction of the values of blood pressure in those who received metformin as monotherapy were observed.

Tiazolinedionas (glitazonas) y riesgo cardiovascular / Tiazolinediones (glytazones) and cardiovascular risk

Las tiazolinedionas son una opción de tratamiento en los pacientes con diabetes tipo 2 cuando no se han alcanzado las metas con los tratamientos de primera línea (metformina y sulfonilureas). Este artículo describe y discute la evidencia sobre la eficacia y la seguridad de las tiazolinedionas (rosiglitazona y pioglitazona)

Tiazolinediones are a treatment option to be added in patients with type 2 diabetes who have not get the goals whentreated with first line treatments (metformin and sulfonylureas). This article describes and discuss the evidence about effi-cacy and safety of two tiazolinediones (rosiglitazone and pioglitazone