Function of s100 protein in coronary atherosclerosis / Función de la proteína s100 en aterosclerosis coronaria

SUMMARY: Atherosclerosis is a complex disease whose pathogenesis includes endothelial activation, accumulation of lipids in the subendothelium, formation of foam cells, fat bands and formation of atherosclerotic plaque. These complex mechanisms involve different cell populations in the intimate sub-endothelium, and the S-100 protein family plays a role in a number of extracellular and intracellular processes during the development of atherosclerotic lesions. The aim of this study was to determine the phenotypic characteristics of smooth muscle cells and the consequent expression of S100 protein in atherosclerotic altered coronary arteries in advanced stages of atherosclerosis. 19 samples of right atherosclerotic coronary arteries in stages of fibro atheroma (type V lesion) and complicated lesions (type VI lesion) have been analyzed. According to the standard protocol, the following primary antibodies have been used in the immunohistochemical analysis: a-smooth muscle actin (α-SMA), vimentin and S-100 protein. All analyzed samples have been in advanced stages of atherosclerosis, fibro atheroma (stage V lesions) and complicated lesions (type VI lesions). Most of them have had the structure of a complicated lesion with atheroma or fibro atheroma as a basis, subsequently complicated by disruption (subtype VI a), hemorrhage (subtype VI b) or thrombosis (subtype VI c), as well as by the presence of several complications on the same sample. Marked hypocellularity is present in the subendothelium of plaques. Cell population at plaque margins is characterized by immunoreactivity to α-SMA, vimentin, and S100 protein. Some of these cells accumulate lipids and look like foam cells. In the cell population at the margins of the plaques, smooth muscle cells of the synthetic phenotype are present, some of which accumulate lipids and demonstrate S100 immunoreactivity. Summarizing numerous literature data and our results, we could assume that smooth muscle cells, due to their synthetic and proliferative activity in the earlier stages of pathogenesis, as well as the consequent expression of S100 protein, could accumulate lipids in the earlier stages of atherosclerosis which, in advanced stages analyzed in this study, result in immunoreactivity of foam cells of smooth muscle origin to S100 protein.

RESUMEN: La aterosclerosis es una enfermedad compleja cuya patogenia incluye activación endotelial, acumulación de lípidos en el subendotelio, formación de células espumosas, bandas grasas y formación de placa aterosclerótica. Estos complejos mecanismos involucran diferentes poblaciones celulares en el subendotelio íntimo, y la familia de proteínas S-100 juega un papel en varios procesos extracelulares e intracelulares durante el desarrollo de lesiones ateroscleróticas. El objetivo de este estudio fue determinar las características fenotípicas de las células de músculo liso y la consecuente expresión de la proteína S100 en arterias coronarias alteradas ateroscleróticas en estadios avanzados de aterosclerosis. Se analizaron 19 muestras de arterias coronarias ateroscleróticas derechas en estadios de fibroateroma (lesión tipo V) y lesiones complicadas (lesión tipo VI). Según el protocolo estándar, en el análisis inmunohistoquímico se utilizaron los siguientes anticuerpos primarios: α-actina de músculo liso (α-SMA), vimentina y proteína S-100. Todas las muestras analizadas han estado en estadios avanzados de aterosclerosis, fibroateroma (lesiones estadio V) y lesiones complicadas (lesiones tipo VI). La mayoría de ellos han tenido la estructura de una lesión complicada con ateroma o fibroateroma como base, complicada posteriormente por disrupción (subtipo VI a), hemorragia (subtipo VI b) o trombosis (subtipo VI c), así como por la presencia de varias complicaciones en la misma muestra. La hipocelularidad marcada estaba presente en el subendotelio de las placas. La población celular en los márgenes de la placa se caracterizaba por inmunorreactividad a α-SMA, vimentina y proteína S100. Algunas de estas células acumulan lípidos y parecen células espumosas. En la población celular en los márgenes de las placas, estaban presentes las células de músculo liso de fenotipo sintético, algunas de las cuales acumulaban lípidos y mostraban inmunorreactividad S100. Resumiendo numerosos datos de la literatura y nuestros resultados, podríamos suponer que las células del músculo liso, debido a su actividad sintética y proliferativa en las primeras etapas de la patogénesis, así como la consecuente expresión de la proteína S100, podrían acumular lípidos en las primeras etapas de la aterosclerosis que, en estadios avanzados analizados en este estudio, dan como resultado inmunorreactividad de células espumosas de origen muscular liso a la proteína S100.

The effects of methanol extract of Galium verum L on cardiac redox state in hypertensive rats

Abstract The aim of this study was to assess the effects of methanol extract of G. verum on redox status of isolated heart of spontaneously hypertensive rats after ischemia. Twenty-four Wistar albino rats were divided into three groups: untreated control rats and rats that received 125 and 250 mg/kg G. verum extract for 4 weeks per os. Index of lipid peroxidation (measured as TBARS) and parameters of antioxidative defence system such as level of reduced glutathione (GSH) and activities of catalase (CAT) and superoxide dismutase (SOD) were spectrophotometrically determined in heart homogenate. The index of lipid peroxidation in heart tissue was lower in both treated groups compared to the control group. On the other hand, the activity of SOD was significantly higher after consumption of both doses, while the activity of CAT was significantly higher only after treatment with a higher dose of extract. Based on our results we might conclude that 4-week treatment with methanol extracts of G. verum has the potential to modulate myocardial redox signaling after ischemia, thus significantly alleviating cardiac oxidative stress and exerting dose-dependent antioxidant properties. Future studies are certainly necessary to fully clarify the role of this plant species in myocardial I-R injury.

Effects of ischemia and omeprazole preconditioning on functional recovery of isolated rat heart / Efeitos da isquemia e pré-condicionamento com omeprazol na recuperação funcional do coração isolado de rato

Abstract Objective: The aim of this study was to compare protective effects of ischemic and potential protective effects of pharmacological preconditioning with omeprazole on isolated rat heart subjected to ischemia/reperfusion. Methods: The hearts of male Wistar albino rats were excised and perfused on a Langendorff apparatus. In control group (CG) after stabilization period, hearts were subjected to global ischemia (perfusion was totally stopped) for 20 minutes and 30 minutes of reperfusion. Hearts of group II (IPC) were submitted to ischemic preconditioning lasting 5 minutes before 20 minutes of ischemia and 30 minutes of reperfusion. In third group (OPC) hearts first underwent preconditioning lasting 5 minutes with 100μM omeprazole, and then submitted 20 minutes of ischemia and 30 minutes of reperfusion. Results: Administration of omeprazole before ischemia induction had protective effect on myocardium function recovery especially regarding to values of systolic left ventricular pressure and dp/dt max. Also our findings are that values of coronary flow did not change between OPC and IPC groups in last point of reperfusion. Conclusion: Based on our results it seems that ischemic preconditioning could be used as first window of protection after ischemic injury especially because all investigated parameters showed continuous trend of recovery of myocardial function. On the other hand, preconditioning with omeprazole induced sudden trend of recovery with positive myocardium protection, although less effective than results obtained with ischemic preconditioning not withstand, we must consider that omeprazole may be used in many clinical circumstances where direct coronary clamping for ischemic preconditioning is not possible. .

Resumo Objetivo: O objetivo deste estudo foi comparar os efeitos protetores de efeitos protetores isquêmicos e potenciais de précondicionamento farmacológico com omeprazol no coração isolado de rato submetido à isquemia/reperfusão. Métodos: Os corações de ratos albinos Wistar machos foram excisados e perfundidos em um aparelho de Langendorff. No grupo controle (grupo I), após o período de estabilização, os corações foram submetidos à isquemia global (a perfusão foi totalmente interrompida) por 20 minutos e 30 minutos de reperfusão. Corações do grupo II (IPC) foram submetidos a précondicionamento isquêmico com duração de 5 minutos antes de 20 minutos de isquemia e 30 minutos de reperfusão. No terceiro grupo (OPC), corações foram submetidos a pré-condicionamento com duração de 5 minutos com 100 μM de omeprazol, e, então, submetidos a 20 minutos de isquemia e 30 minutos de reperfusão. Resultados: A administração de omeprazol antes da indução da isquemia teve efeito protetor sobre a recuperação funcional do miocárdio especialmente em relação aos valores de pressão sistólica ventricular esquerda e dp/dt max. Também os nossos achados são de que os valores de fluxo coronário não se alteraram entre os grupos OPC e IPC no último ponto de reperfusão. Conclusão: Com base nos nossos resultados, o pré-condicionamento isquêmico poderia ser usado como primeira janela de proteção após a lesão isquêmica, especialmente porque todos os parâmetros analisados apresentam tendência contínua de recuperação da função do miocárdio. Por outro lado, o pré-condicionamento induzido com omeprazol apresenta tendência repentina de recuperação com proteção miocárdio positiva, embora menos efetiva da obtida com o pré-condicionamento isquêmico. Devemos considerar que o omeprazol pode ser usado em muitas circunstâncias clínicas em que o pinçamento coronariano direto para pré-condicionamento isquêmico não é possível. .

Effectiveness of clozapine, haloperidol and chlorpromazine in schizophrenia during a five-year period / Eficácia da clozapina, haloperidol e clorpromazina na esquizofrenia em um período de cinco anos

OBJECTIVE: The aim of our study was to evaluate the effects of low doses of clozapine in flexible regime in comparison with haloperidol and chlorpromazine in long term. METHOD: The naturalistic study was prospective, active-controlled with 325 adult outpatients of both genders (140 females), with mean year age of 34.8 (range 21-57), suffering from chronic schizophrenia. The first onset of illness was at the mean of 27.9 years (range 17-38), and subjects had the mean year age of 4.1±0.5 previous relapses. The patients were allocated to receive haloperidol (105 subjects, dose range 2-15 mg), chlorpromazine (n=105, 100-400 mg) or clozapine (n=115, 75-600 mg). The scores of psychometric instruments (GWB, PANSS, CGI) were regularly assessed during 5 year period. RESULTS: The sixty-six responders were included in per-protocol analysis: 12, 10 and 16 with positive and 7, 6 and 15 with negative schizophrenic syndrome in haloperidol, chlorpromazine and clozapine group, respectively. The statistically significant differences in all psychometric scores was found, for both schizophrenic syndromes, favoring clozapine. The distribution of eighteen different types of adverse events, which we noted, were significantly different among treatment groups ( ÷2=315.7, df=34, p<0.001). Clozapine was safer and had fewer adverse effects (average of 0.9 adverse events per patient) than haloperidol (2.7) and chlorpromazine (3.2). CONCLUSIONS: Clozapine, in low doses of flexible regime, in long term (five years) showed better effectiveness in chronic schizophrenics with positive and negative symptoms than typical antipsychotics.

OBJETIVO: O propósito deste estudo foi avaliar os efeitos de baixas doses de clozapina em regime flexível comparando com o uso de haloperidol e clorpromazina por período de 5 anos. MÉTODO: Um estudo prospectivo naturalístico, ativo-controlado foi realizado com 325 pacientes com idade média de 34,8 (variância 21-57). Todos com diagnóstico de esquizofrenia. No primeiro surto da doença os pacientes apresentavam idade média de 27,9 anos (variância 17-38) e os surtos subsequentes apareceram em média 4,1±0,5 anos após. Os pacientes foram orientados a receberem haloperidol (105 pacientes com dose entre 2 e 15 mg), clorpromazina (105 pacientes com dose entre 100 e 400 mg) e clozapina (115 pacientes com dose entre 75 e 600 mg). Os instrumentos psicométricos utilizados (GWB, PANSS e CGI) foram regularmente empregados durante os 5 anos do estudo. RESULTADOS: Os 66 pacientes respondedores ao tratamento foram incluídos no protocolo de análise: 12, 10 e 16 apresentavam síndrome esquizofrênica positiva e 7, 6 e 15 síndrome negativa esquizofrênica com haloperidol, clorpromazina e clozapina, respectivamente. Diferenças estatísticas significantes foram observadas em todas as avaliações psicométricas em ambas síndromes esquizofrênicas favorecendo a clozapina. A distribuição de 18 tipos de efeitos colaterais observados foi diferente de modo significativo entre os 3 grupos estudados. A clozapina foi a droga que apresentou menos efeitos colaterais. CONCLUSÃO: A clozapina administrada por longo termo em pequenas doses em regime flexível apresenta melhor eficácia nas síndromes esquizofrênicas quando comparada a outras drogas antipsicóticas.