Camila Prim

Use of rosiglitazone before and after vascular injury in hypercholesterolemic rabbits: Assessment of neointimal formation

ObjectivesTo analyse the effects of rosiglitazone administered at different times on neointimal formation in hypercholesterolemic rabbits following vascular injury.MethodsThirty-nine rabbits on a hypercholesterolemic diet were included. The animals underwent balloon catheter injury to the right iliac artery on day 14. They were divided into three groups as follows: control group, 13 rabbits without rosiglitazone; group I, 13 rabbits treated with rosiglitazone (3 mg/Kg body weight/day) for 28 days after the vascular injury; and group II, 13 rabbits treated with rosiglitazone (3 mg/Kg body weight/day) during all the experiment (42 days). Histological analysis was done by an experienced pathologist who was unaware of the rosiglitazone treatment. Histomorphometric parameters were performed by calculation of the luminal and intimal layer area, and intima/media layer area ratio (the area of the intimal layer divided by the area of the medial layer).ResultsIntimal area was significantly lower in group II vs. CG (p = 0.024) and group I (p = 0.006). Luminal layer area was higher in group II vs. CG (p < 0.0001) and group I (p < 0.0001). Intima/media layer area ratio was equal between CG and group I. Intima/media layer ratio area was significantly lower in group II vs. control group (p < 0.021) and group I (p < 0.003). There was a significant reduction of 65% and 71% in intima/media layer area ratio in group II vs. control group and group I, respectively.ConclusionPretreatment with rosiglitazone in hypercholesterolemic rabbits submitted to vascular injury significantly reduces neointimal formation.

Rosiglitazona e lesão vascular em coelhos hipercolesterolêmicos: avaliação da formação neointimal

FUNDAMENTO: El uso de rosiglitazona ha estado siendo el objeto de extensas discusiones. OBJETIVO: Evaluar los efectos de la rosiglitazona en las arterias iliacas, en el local de la injuria y en la arteria contralateral, de conejos hipercolesterolemicos sometidos a la lesion por cateter-balon. METODOS: Conejos blancos machos recibieron una dieta hipercolesterolemica a traves 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 lesion por cateter-balon en la arteria iliaca derecha en el 14o dia. RESULTADOS: En la arteria iliaca contralateral, no hubo diferencia significativa en la razon entre las areas intima y media (RIM) entre los grupos GR y GC. La rosiglitazona no redujo la probabilidad de lesiones tipo I, II o III (72,73% vs 92,31%; p=0,30) y lesiones tipo IV o V (27,27% vs 7,69%; p=0,30). En la arteria iliaca homolateral, el area intima era significantemente menor en el GR cuando comparado al GC (p = 0,024). El area luminal era mayor en el GR cuando comparado al GC (p < 0,0001). Hubo una reduccion significante del 65% en la IMR en el GR cuando comparado al GC (p = 0,021). Ningun de los criterios histologicos para lesiones ateroscleroticas tipos I a V (American Heart Association) se encontraron en la arteria iliaca homolateral. CONCLUSION: Estos hallazgos demuestran que la administracion de rosiglitazona por 6 semanas impide la aterogenesis en el local de la lesion, pero no en un vaso distante del sitio de la lesion.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% vs 92.31%; p=0.30) and type IV or V lesions (27.27% vs 7.69%; 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% 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.

Rosiglitazone and vascular injury in hypercholesterolemic rabbits: neointimal formation assessment

FUNDAMENTO: El uso de rosiglitazona ha estado siendo el objeto de extensas discusiones. OBJETIVO: Evaluar los efectos de la rosiglitazona en las arterias iliacas, en el local de la injuria y en la arteria contralateral, de conejos hipercolesterolemicos sometidos a la lesion por cateter-balon. METODOS: Conejos blancos machos recibieron una dieta hipercolesterolemica a traves 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 lesion por cateter-balon en la arteria iliaca derecha en el 14o dia. RESULTADOS: En la arteria iliaca contralateral, no hubo diferencia significativa en la razon entre las areas intima y media (RIM) entre los grupos GR y GC. La rosiglitazona no redujo la probabilidad de lesiones tipo I, II o III (72,73% vs 92,31%; p=0,30) y lesiones tipo IV o V (27,27% vs 7,69%; p=0,30). En la arteria iliaca homolateral, el area intima era significantemente menor en el GR cuando comparado al GC (p = 0,024). El area luminal era mayor en el GR cuando comparado al GC (p < 0,0001). Hubo una reduccion significante del 65% en la IMR en el GR cuando comparado al GC (p = 0,021). Ningun de los criterios histologicos para lesiones ateroscleroticas tipos I a V (American Heart Association) se encontraron en la arteria iliaca homolateral. CONCLUSION: Estos hallazgos demuestran que la administracion de rosiglitazona por 6 semanas impide la aterogenesis en el local de la lesion, pero no en un vaso distante del sitio de la lesion.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% vs 92.31%; p=0.30) and type IV or V lesions (27.27% vs 7.69%; 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% 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.

Effects of rosiglitazone on contralateral iliac artery after vascular injury in hypercholesterolemic rabbits

BackgroundThe objective was to evaluate the effects of rosiglitazone on iliac arteries of hypercholesterolemic rabbits undergoing balloon catheter injury in the contralateral iliac arteries.MethodsWhite male rabbits were fed a hypercholesterolemic diet for 6 weeks and divided into two groups as follows: rosiglitazone group, 14 rabbits treated with rosiglitazone (3 mg/Kg body weight/day) during 6 weeks; and control group, 18 rabbits without rosiglitazone treatment. All animals underwent balloon catheter injury of the right iliac artery on the fourteenth day of the experiment.ResultsThere was no significant difference in intima/media layer area ratio between the control group and the rosiglitazone group. Rosiglitazone did not reduce the probability of lesions types I, II, or III (72.73% vs. 92.31%; p = 0.30) and types IV or V (27.27% vs. 7.69%; p = 0.30). There were no differences in the extent of collagen type I and III deposition or in the percentage of animals with macrophages in the intima layer. The percentage of rabbits with smooth muscle cells in the intima layer was higher in rosiglitazone group (p = 0.011).ConclusionThese findings demonstrate that rosiglitazone given for 6 weeks did not prevent atherogenesis at a vessel distant from the injury site.

Conceitos atuais e perspectivas na prevenção da degeneração macular relacionada à idade

Os autores fazem revisao bibliografica a respeito dos principais antioxidantes utilizados na pratica diaria atualmente para prevencao da progressao da degeneracao macular relacionada com a idade (DMRI), enfatizando o mecanismo de acao de cada substância bem como as possiveis complicacoes relacionadas ao uso excessivo destes componentes.

Rosiglitazona y lesión vascular en conejos hipercolesterolémicos

FUNDAMENTO: El uso de rosiglitazona ha estado siendo el objeto de extensas discusiones. OBJETIVO: Evaluar los efectos de la rosiglitazona en las arterias iliacas, en el local de la injuria y en la arteria contralateral, de conejos hipercolesterolemicos sometidos a la lesion por cateter-balon. METODOS: Conejos blancos machos recibieron una dieta hipercolesterolemica a traves 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 lesion por cateter-balon en la arteria iliaca derecha en el 14o dia. RESULTADOS: En la arteria iliaca contralateral, no hubo diferencia significativa en la razon entre las areas intima y media (RIM) entre los grupos GR y GC. La rosiglitazona no redujo la probabilidad de lesiones tipo I, II o III (72,73% vs 92,31%; p=0,30) y lesiones tipo IV o V (27,27% vs 7,69%; p=0,30). En la arteria iliaca homolateral, el area intima era significantemente menor en el GR cuando comparado al GC (p = 0,024). El area luminal era mayor en el GR cuando comparado al GC (p < 0,0001). Hubo una reduccion significante del 65% en la IMR en el GR cuando comparado al GC (p = 0,021). Ningun de los criterios histologicos para lesiones ateroscleroticas tipos I a V (American Heart Association) se encontraron en la arteria iliaca homolateral. CONCLUSION: Estos hallazgos demuestran que la administracion de rosiglitazona por 6 semanas impide la aterogenesis en el local de la lesion, pero no en un vaso distante del sitio de la lesion.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% vs 92.31%; p=0.30) and type IV or V lesions (27.27% vs 7.69%; 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% 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.