Objetivo: Avaliar se a administração sistêmica de cilostazol reduz a hiperplasia neointimal nas artérias ilíacas de suínos submetidas a angioplastia com cateter balão. Métodos: O trabalho foi desenvolvido na Unidade de Experimentação Animal do Hospital de Clínicas de Porto Alegre. Vinte suínos foram submetidos a angioplastia com cateter balão 6 x 40 mm na artéria ilíaca comum direita, guiada por ultrassonografia com Doppler. Os animais foram randomizados em dois grupos: grupo 1 (n = 10), no qual foi administrado cilostazol 50 mg em duas doses diárias, e grupo 2 (n = 10), considerado controle. Após 30 dias, os animais foram sacrificados, e as artérias ilíacas preparadas para análise histológica. Os cortes histológicos foram digitalizados e analisados por morfometria digital. A análise estatística foi realizada com o teste t de Student e o de Mann-Whitney. Resultados: Comparando as artérias ilíacas submetidas a angioplastia com as não submetidas a angioplastia, houve hiperplasia neointimal significativa (0,228 versus 0,119 mm2; p = 0,0001). Nas artérias submetidas a angioplastia, não houve diferença entre o grupo 1 (cilostazol) e o grupo 2 (controle) na área do lúmen (2,277 versus 2,575 mm2; p = 0,08), área da íntima (0,219 versus 0,237 mm2; p = 0,64), área da média (2,262 versus 2,393 mm2; p = 0,53) e no percentual de obstrução neointimal (8,857 versus 9,257 %; p = 0,82). Conclusão: O uso de cilostazol 50 mg em duas doses diárias não reduziu a hiperplasia neointimal em artérias ilíacas de suínos submetidas a angioplastia com cateter balão. / Objective: To evaluate whether systemic administration of cilostazol reduces neointimal hyperplasia in the iliac arteries of pigs after balloon angioplasty. Methods: This study was conducted in the Experimental Animal Unit of Hospital de Clínicas de Porto Alegre, Brazil. Twenty pigs underwent angioplasty of the right common iliac artery under Doppler ultrasound guidance using 6x40-mm balloon catheters. The animals were randomized to one of two groups: group 1 (n = 10) received 50 mg cilostazol in two doses a day; and group 2 (n = 10) was the control group. After 30 days, the animals were killed and their iliac arteries were prepared for histological analysis. Histological images were digitalized and analyzed using digital morphometry. The Student t and the Mann-Whitney tests were used for statistical analyses. Results: Iliac arteries that underwent angioplasty had significantly more neointimal hyperplasia than those with no angioplasty (0.228 versus 0.119 mm2; p = 0.0001) Group 1 (cilostazol) and 2 (control) had no significant differences in lumen (2.277 versus 2.575 mm2; p = 0.08), intima (0.219 versus 0.237 mm2; p = 0.64) or media (2.262 versus 2.393 mm2; p = 0.53) area, or in percentage of neointimal obstruction (8.857 versus 9.257 %; p = 0.82). Conclusion: The use of 50 mg cilostazol in two doses a day did not reduce neointimal hyperplasia in iliac arteries of pigs that underwent balloon angioplasty.

The intimal hyperplasia remains as a challenge to vascular interventions because it causes vessel lumen reduction with weaken blood flow to the tissues, leading to cardiovascular complications such as myocardial infarction, stroke and limb amputations. Moringa oleifera has shown efficiency to reduce serum cholesterol by 52% and 86% of atherosclerotic plaque in the carotid arteries of rabbits with hypercholesterolemic regimen, showing thus considerable potential to prevent cardiovascular diseases and myointimal hyperplasia. The Moringa oleifera has a powerful antioxidant activity, effects: anti-inflammatory, hipolipidemic, hypocholesterolemic, anti-hypertensive, anti-tumor and anti-diabetes responses, resulting from its polyphenol components. These effects may converge for inhibiting myointimal hyperplasia. The sample consisted of rabbits with atherosclerosis induced by egg yolk and endothelial denudation of the right external iliac artery by balloon. The Group “Cz” was treated with cilostazol 50 mg/day. Group “Mo” treated with 200 mg/kg body weight daily of Moringa and Group “SF” was treated with 10 ml/day, all orally treated for five weeks. Primary variable was the mean difference of myointimal hyperplasia. The secondary variables were the average vessel wall thickness in each group, the means of total cholesterol, triglycerides, HDL, LDL, VLDL and immunohistochemistry: the average area of C4d and monoclonal HHF35. The sample was estimated in 30 rabbits divided in three groups of ten animals. As results, the average difference of myointimal hyperplasia assessed by ANOVA analysis of variance (one way) resulted in a statistically significant difference between groups (p<0.0001), with higher average reduction of myointimal wall thickness in the group “Cz”, what shows a better response to treatment with cilostazol. The evaluation of the initial and final average of total cholesterol by analysis of variance; ANOVA (two way) between the groups showed statistically significant results (p=0.0043), also presenting greater reduction by treatment with cilostazol. HDL initial and final means in each group evaluated by analysis of variance; ANOVA (two-way) between the groups, showed a statistically significant difference (p=0.0044), reflecting higher average or increased HDL by treatment with Moringa. As conclusion, the average difference of myointimal hyperplasia in the iliac artery of rabbits with arteriosclerosis, treated with Moringa oleifera compared to cilostazol, presented a greater reduction in cilostazol treatment group. / A hiperplasia da íntima permanece um desafio às intervenções vasculares por provocar redução da luz dos vasos com diminuição do fluxo sanguíneo aos tecidos, levando a complicações cardiovasculares como infarto do miocárdio, acidente vascular cerebral e amputação de membros. A Moringa oleifera tem mostrado reduzir o colesterol sérico em 52% e a placa aterosclerótica em 86% nas carótidas de coelhos em dieta hipercolesterolêmica, mostrando assim, potencial considerável para prevenir doenças cardiovasculares e a hiperplasia miointimal. A Moringa oleifera apresenta potente ação antioxidante, efeitos: anti-inflamatório, hipolipemiante, hipocolesterolemiante, anti-hipertensivo, antitumoral e antidiabético, resultantes de seus componentes polifenóicos. Esses efeitos podem convergir para a inibição da hiperplasia miointimal. A amostra foi constituída de coelhos com aterosclerose induzida pela gema de ovo e desnudação endotelial da artéria ilíaca externa direita por balão. O Grupo (Cz) foi tratado com Cilostazol 50 mg/dia, o Grupo (Mo) tratado com 200 mg/kg de peso corporal de moringa ao dia e o Grupo (SF) tratado com 10 mL/dia, todos tratados por via oral durante cinco semanas. A variável primária foi a diferença de média de hiperplasia miointimal. As variáveis secundárias foram a média de espessura da parede em cada grupo, as médias de Colesterol total, Triglicerídeos, HDL, LDL, VLDL e na imuno-histoquímica: a média de área de C4d e de HHF35 monoclonal. A amostra foi estimada em 30 coelhos, divididos em três grupos de dez animais. Nos resultados, a diferença de média de hiperplasia miointimal avaliada por análise de variância ANOVA (one way) resultou em diferença estatísticamente significante entre os grupos (p<0,0001), com maior redução de média de espessura de parede miointimal no grupo (Cz), mostrando melhor resposta ao tratamento com o cilostazol. A avaliação da média inicial e final do colesterol total pela análise de variância; ANOVA (two way) entre os grupos, apresentou resultados estatísticamente significativos (p=0,0043), mostrando também, maior redução pelo tratamento com o cilostazol. A média inicial e final do HDL em cada grupo, avaliados pela análise de variância; ANOVA (two-way), entre os grupos, apresentou diferença estatisticamente significantes (p=0,0044), evidenciando maior média ou aumento de HDL pelo tratamento com a Moringa oleifera. Em conclusão, a diferença de média de hiperplasia miointimal na artéria ilíaca de coelhos com aterosclerose, tratados com Moringa oleifera, comparado com cilostazol, apresentou maior redução no grupo tratado com cilostazol.

Cerebral small vessel pathology is now known to be associated with the development of cognitive impairment and mild motor impairments such as gait disturbance in a variety of neurodegenerative diseases. This dissertation explores the hypothesis that blood brain barrier dysfunction is an early event in cerebral ischemia and contributes to the development of cerebral small vessel disease (CSVD). A common rodent model of CSVD is permanent bilateral common carotid artery occlusion in the rat. This model was used to study several aspects of the progression of CSVD including the timecourse of blood brain barrier permeability changes following the onset of ischemia, gait disturbance, the expression of tight junction proteins and cytokine expression. It was determined that BBB permeability was elevated for 2 weeks following BCCAO and ischemic rats displayed lower gait velocity. There was no change in expression of TJ proteins. However, ischemic rats had higher levels of some proinflammatory cytokines and chemokines in brain tissue with no obvious changes in plasma levels. The mechanisms underlying the increase in BBB permeability were studied in vitro using artificial barriers made of confluent rat brain microvascular endothelial cells. Cerebral ischemia has been reported to cause an increase in plasma toxicity, likely by elevating the numbers of circulating microparticles (MPs). MPs isolated from the plasma of ischemic rats were applied to artificial barriers where it was found that they act mainly as vectors of TNF-α signaling. MPs induce activation of caspase-3 and the Rho/Rho kinase pathways. It is concluded that most of the increase in barrier permeability is due to apoptosis and disassembly of actin cytoskeleton and disruption of adherens junctions IV and not an increase in transcellular transport. The effects of treatment with the type III phosphodiesterase inhibitor cilostazol on dye extravasation in the brain, glial activation, white matter damage and motor performance were evaluated. It was determined that cilostazol could improve the increased BBB permeability and gait disturbance and microglial activation in optic tract following BCCAO. Also, the effects of treatment with cilostazol on plasma toxicity in vivo (24h and 14d following BCCAO) and artificial barriers (in vitro) were assessed. It was found that cilostazol could reduce plasma toxicity at 24h and improve increased endothelial barrier permeability that is induced by MP treatment respectively. In summary BBB dysfunction occurs in the rat model of chronic cerebral hypoperfusion with no differences in expression of TJ proteins. There is a mild motor disturbance in the form of lower gait velocity following BCCAO. Cytokines released in brain tissue may be associated with pathological consequences following BCCAO while there is no significant difference in plasma levels and circulating MPs may play a role in BBB dysfunction.