Underuse of reperfusion therapy with systemic thrombolysis in high-risk acute pulmonary embolism in a Portuguese center.

INTRODUCTION: Reperfusion therapy is generally recommended in acute high-risk pulmonary embolism (HR-PE), but several population-based studies report that it is underused. Data on epidemiology, management and outcomes of HR-PE in Portugal are scarce. OBJECTIVE: To determine the reperfusion rate in HR-PE patients, the reasons for non-reperfusion, and how it influences outcomes. METHODS: In this retrospective cohort study of consecutive HR-PE patients admitted to a thromboembolic disease referral center between 2008 and 2018, independent predictors for non-reperfusion were assessed by multivariate logistic regression. PE-related mortality and long-term MACE (cardiovascular mortality, PE recurrence and chronic thromboembolic disease) were calculated according to the Kaplan-Meier method. Differences stratified by reperfusion were assessed using the log-rank test. RESULTS: Of 1955 acute PE patients, 3.8% presented with hemodynamic instability. The overall reperfusion rate was 50%: 35 patients underwent systemic thrombolysis, one received first-line percutaneous embolectomy and one rescue endovascular treatment. Independent predictors of non-reperfusion were: age, with >75 years representing 12 times the risk of non-treatment (OR 11.9, 95% CI 2.7-52.3, p=0.001); absolute contraindication for thrombolysis (31.1%), with recent major surgery and central nervous system disease as the most common reasons (OR 16.7, 95% CI 3.2-87.0, p<0.001); and being hospitalized (OR 7.7, 95% CI 1.4-42.9, p=0.020). At a mean follow-up of 2.5±3.3 years, the survival rate was 33.8%. Although not reaching statistical significance for hospital mortality, mortality in the reperfusion group was significantly lower at 30 days, 12 months and during follow-up (relative risk reduction of death of 64% at 12 months, p=0.013). Similar results were found for MACE. CONCLUSIONS: In this population, the recommended reperfusion therapy was performed in only 50% of patients, with advanced age and absolute contraindications to fibrinolysis being the main predictors of non-reperfusion. In this study, thrombolysis underuse was associated with a significant increase in short- and long-term mortality and events.

Effect of CASC15 on apoptosis and oxidative stress of cardiomyocytes after hypoxia/reperfusion injury.

INTRODUCTION AND OBJECTIVES: The increasing incidence of ischemic heart disease is a serious threat to human health. Increased CASC15, a long non-coding RNA, has been shown to adversely affect cardiac muscle. The objective of this paper was to explore the effect of CASC15 on a cell model of myocardial infarction and its possible mechanism. METHODS: H9c2 cells were selected to establish the myocardial infarction model through hypoxia/reoxygenation (H/R) treatment. The expression of CASC15 was attenuated by cell transfection in vitro. The level of CASC15 was detected by RT-qPCR. Cell viability was detected by CCK-8 assay, and cell apoptosis was assessed by flow cytometry. The content of MDA and the activity of SOD and GSH-Px were measured by ELISA. Luciferase reporter gene assay was used to determine the relationship between CASC15 and miRNA. RESULTS: CASC15 expression was increased in H/R-treated H9c2 cells. Overexpression of CASC15 adversely affected cell viability and promoted H/R-induced oxidative stress. Inhibition of CASC15 promoted cell viability and suppressed cell apoptosis and oxidative stress damage. Additionally, luciferase reporter gene assay confirmed the targeting relationship between CASC15 and miR-542-3p, and attenuating CASC15 expression enhanced the level of miR-542-3p. Reduction of miR-542-3p weakened the viability of the H/R cell model, increased apoptosis, and enhanced oxidative stress damage. CONCLUSION: This study suggests that overexpression of CASC15 may inhibit the viability of H9c2 cells, promote apoptosis and induce oxidative stress through targeted regulation of miR-542-3p expression.

Reperfusion therapy for acute ischemic stroke: where are we in 2023? / Terapia de reperfusão para o acidente vascular isquêmico agudo: onde estamos em 2023?

Abstract Over the last three decades, stroke care has undergone significant transformations mainly driven by the introduction of reperfusion therapy and the organization of systems of care. Patients receiving treatment through a well-structured stroke service have a much higher chance of favorable outcomes, thereby decreasing both disability and mortality. In this article, we reviewed the scientific evidence for stroke reperfusion therapy, including thrombolysis and thrombectomy, and its implementation in the public health system in Brazil.

Resumo Nas últimas três décadas, o tratamento do AVC sofreu transformações significativas, impulsionadas principalmente pela introdução das terapias de reperfusão e pela organização dos serviços de AVC. Os pacientes que recebem tratamento em um serviço de AVC bem estruturado têm uma probabilidade muito maior de resultados favoráveis, diminuindo assim a incapacidade funcional e a mortalidade. Neste artigo, revisamos as evidências científicas para as terapias de reperfusão do AVC, incluindo trombólise e trombectomia e sua implementação no sistema público de saúde no Brasil.

O Pré-Condicionamento com Dexmedetomidina Atenua a Lesão de Isquemia/Reperfusão Miocárdica em Ratos, Suprimindo a Mitofagia Via Ativação do Receptor Α2-Adrenérgico / Dexmedetomidine Preconditioning Attenuates Myocardial Ischemia/Reperfusion Injury in Rats by Suppressing Mitophagy Via Activating Α2-Adrenergic Receptor

Resumo Fundamento A dexmedetomidina (DEX), um agonista específico do receptor α2-adrenérgico, é protetora contra lesão de isquemia/reperfusão miocárdica (I/R). No entanto, a associação entre a cardioproteção induzida pelo pré-condicionamento DEX e a supressão da mitofagia permanece pouco clara. Objetivo Portanto, nosso objetivo foi investigar se o pré-condicionamento com DEX alivia a I/R, suprimindo a mitofagia via ativação do receptor α2-adrenérgico. Método Sessenta corações de ratos isolados foram tratados com ou sem DEX antes de induzir isquemia e reperfusão; um antagonista do receptor α2-adrenérgico, a ioimbina (YOH), também foi administrado antes da isquemia, isoladamente ou com DEX. A frequência cardíaca (FC), pressão diastólica do ventrículo esquerdo (PDVE), pressão diastólica final do ventrículo esquerdo (PDFVE), taxa máxima e mínima de desenvolvimento da pressão ventricular esquerda (±dp/dtmax) e tamanho do infarto do miocárdio foram medidos. A ultraestrutura mitocondrial e as autofagossomas foram avaliadas por microscopia eletrônica de transmissão. O potencial de membrana mitocondrial e os níveis de espécies reativas de oxigênio (ROS) foram medidos usando os ensaios JC-1 e diacetato de diclorodi hidrofluoresceína, respectivamente. Os níveis de expressão das proteínas associadas à mitofagia Beclin1, relação LC3II/I, p62, PINK1 e Parkin foram detectados por western blotting. Resultados Em comparação com o grupo controle, no grupo isquemia/reperfusão, a FC, PDVE e ±dp/dtmax foram notavelmente diminuídas (p<0,05), enquanto os tamanhos da PDFVE e do infarto aumentaram significativamente (p<0,05). O pré-condicionamento com DEX melhorou significativamente a disfunção cardíaca, reduziu o tamanho do infarto do miocárdio, manteve a integridade estrutural mitocondrial, aumentou o potencial de membrana mitocondrial, inibiu a formação de autofagossomas e diminuiu a produção de ROS e a relação Beclin1, relação LC3II/I, expressão PINK1, Parkin e p62(p<0,05). Quando DEX e YOH foram combinados, o YOH cancelou o efeito da DEX, enquanto o uso de YOH sozinha não teve efeito. Conclusão Portanto, o pré-condicionamento DEX foi cardioprotetor contra I/R em ratos, suprimindo a mitofagia por meio da ativação do receptor α2-adrenérgico.

Abstract Background Dexmedetomidine (DEX), a specific α2-adrenergic receptor agonist, is protective against myocardial ischemia/reperfusion injury (MIRI). However, the association between DEX preconditioning-induced cardioprotection and mitophagy suppression remains unclear. Objective Hence, we aimed to investigate whether DEX preconditioning alleviates MIRI by suppressing mitophagy via α2-adrenergic receptor activation. Method Sixty isolated rat hearts were treated with or without DEX before inducing ischemia and reperfusion; an α2-adrenergic receptor antagonist, yohimbine (YOH), was also administered before ischemia, alone or with DEX. The heart rate (HR), left ventricular diastolic pressure (LVDP), left ventricular end-diastolic pressure (LVEDP), maximal and minimal rate of left ventricular pressure development (±dp/dtmax), and myocardial infarction size were measured. The mitochondrial ultrastructure and autophagosomes were assessed using transmission electron microscopy. Mitochondrial membrane potential and reactive oxygen species (ROS) levels were measured using JC-1 and dichloride hydrofluorescein diacetate assays, respectively. The expression levels of the mitophagy-associated proteins Beclin1, LC3II/I ratio, p62, PINK1, and Parkin were detected by western blotting. Results Compared with the control group, in the ischemia/reperfusion group, the HR, LVDP, and ±dp/dtmax were remarkably decreased (p< 0.05), whereas LVEDP and infarct sizes were significantly increased (p< 0.05). DEX preconditioning significantly improved cardiac dysfunction reduced myocardial infarction size, maintained mitochondrial structural integrity, increased mitochondrial membrane potential, inhibited autophagosomes formation, and decreased ROS production and Beclin1, LC3II/I ratio, PINK1, Parkin, and p62 expression(p< 0.05). When DEX and YOH were combined, YOH canceled the effect of DEX, whereas the use of YOH alone had no effect. Conclusion Therefore, DEX preconditioning was cardioprotective against MIRI in rats by suppressing mitophagy via α2-adrenergic receptor activation.

Could retrograde reperfusion combined with washout technique broaden the applicability of marginal grafts in liver transplantation? Intra-operative and short-term outcomes of a prospective cohort / A reperfusão retrógrada combinada com a lavagem do enxerto pode ampliar a aceitabilidade de fígados limítrofes no transplante hepático? Resultados intraoperatórios e precoces de uma coorte prospectiva

ABSTRACT Introduction: many revascularization techniques were designed to reduce the imbalance of ischemia-reperfusion injury. This study's objective is to evaluate retrograde reperfusion (RR) compared to sequential anterograde reperfusion (AR), with and without the washout technique (WO). Method: this prospective cohort study collected data from 94 deceased donor orthotopic liver transplants and divided it into three groups: RR with WO (RR+WO), AP with WO (AR+WO), and AP without WO (AR). This study did not assign the reperfusion technique to the participants. The primary outcome considered the early graft dysfunction, and secondary outcomes included post-reperfusion syndrome (PRS), post-reperfusion lactate, surgery fluid balance, and vasoactive drug dose during the surgery. Results: 87 patients were submitted to the final analysis-29 in the RR+WO group, 27 in the AR+WO group, and 31 in the AR group. Marginal grafts prevalence was not significantly different between the groups (34% vs. 22% vs. 23%; p=0.49) and early graft dysfunction occurred at the same rate (24% vs. 26% vs. 19%; p=0.72). RR+WO reduced serum post-reperfusion lactate (p=0.034) and the incidence of significant PRS (17% vs. 33% vs. 55%; p=0.051), but norepinephrine dosing >0.5mcg/kg/min were not different during the surgery (20,7% vs. 29,6% vs. 35,5%, p=0.45). Conclusions: primary outcome was not significantly different between the groups; however, intraoperative hemodynamic management was safer using the RR+WO technique. We theorized that the RR+WO technique could reduce the incidence of PRS and benefit marginal graft survival following diseased donor orthotopic liver transplantation.

RESUMO Introdução: várias técnicas de reperfusão foram desenvolvidas a fim de reduzir o dano da lesão induzida por isquemia-reperfusão. Este estudo objetivou avaliar a reperfusão retrograda (RR) comparado com a reperfusão anterógrada (AR), com e sem a realização da técnica de lavagem do enxerto (WO). Métodos: coorte prospectiva com 94 transplantes ortotópicos de fígado de doador falecido divididos em três grupos: RR com WO (RR+WO), reperfusão anterógrada com WO (AR+WO), e AR sem WO (AR). Este estudo não designou a técnica de reperfusão entre os participantes. O desfecho primário considerou a disfunção precoce do enxerto, e os desfechos secundários incluíram a síndrome pós-reperfusão (SPR), lactato pós-reperfusão, balanço hídrico operatório, e uso de drogas vasoativas durante o ato peratório. Resultados: 87 pacientes foram submetidos para consolidação dos dados-29 no RR+WO, 27 no AR+WO, e 31 no AR. A prevalência de enxertos maginais não diferiu entre os grupos (34% vs 22% vs 23%; p=0,49). Disfunção precoce do enxerto ocorreu em uma proporção similar (24% vs 26% vs 19%; p=0,72). RR+WO reduziu o lactato sérico pós-reperfusão (p=0,034) e a incidência de SPR severa (17% vs 33% vs 55%; p=0,051), entretanto a infusão de noradrenalina >0,5mcg/kg/min não foi diferente durante a cirurgia (20,7% vs 29,6% vs 35,5%, p=0,45). Conclusões: o desfecho primário não diferiu significativamente entre os grupos; entretanto, o manejo hemodinâmico intra-operatório foi mais seguro no grupo RR+WO. Nós teorizamos que a técnica RR+WO pode reduzir a SPR e beneficiar enxertos marginais no transplante de fígado.

Comparison of protective effects of alprostadil with Salvia miltiorrhiza against myocardial ischemia-reperfusion injury in rats.

OBJECTIVES: Our study aimed to investigate the effects of alprostadil and Salvia miltiorrhiza extract on myocardial ischemia-reperfusion injury (IRI) and related underlying molecular mechanisms. METHODS: A myocardial IRI model was established in Wistar rats via surgical ligation of the left anterior descending coronary artery followed by loosening of the occlusion. The rats were divided into four groups: saline, sham, alprostadil, and S. miltiorrhiza. Rats in the saline and sham groups were injected with normal saline by tail vein once daily for 10 consecutive days. Rats in the S. miltiorrhiza and alprostadil groups were injected with S. miltiorrhiza extract (20 µg/kg) or alprostadil. Histological differences in myocardial tissues between rats in the sham group and in the myocardial IRI model were observed by hematoxylin and eosin staining. India ink perfusion was used to quantify the number of capillary microvessels. Real-time quantitative reverse transcription polymerase chain reaction was used to determine serum expression levels of soluble intercellular adhesion molecule (sICAM), soluble vascular adhesion molecule (sVCAM), CD11b and CD18. RESULTS: The alprostadil and S. miltiorrhiza groups had significantly higher numbers of microvessels than the saline group. Serum sICAM and sVCAM expression was significantly reduced in the alprostadil and S. miltiorrhiza groups. Meanwhile, sICAM and sVCAM in the alprostadil group were markedly lower than in the S. miltiorrhiza group. Moreover, the alprostadil group had markedly lower mRNA expression of CD11b and CD18, which were clearly lower than in the S. miltiorrhiza group. CONCLUSION: Alprostadil may have cardioprotective effects for myocardial IRI, with down-regulated expression of sICAM, sVCAM, CD11b, and CD18.

Preditores de Mortalidade Hospitalar nos Pacientes Tratados por Angioplastia Primária: Um Estudo de Caso-Controle Multicêntrico / Predictors of Hospital Mortality Based on Primary Angioplasty Treatment: A Multicenter Case-Control Study

Resumo Fundamento A estratificação do risco de morte dos pacientes no contexto da angioplastia primária (ATC) é fundamental. Objetivo Identificar os fatores relacionados ao desfecho morte em pacientes submetidos a ATC. Métodos Estudo de caso-controle, utilizando como fonte de dados um registro brasileiro. A associação entre cada variável e o desfecho óbito foi avaliada via modelo de regressão logística binária. Consideramos significativo p<0,05. Resultados Foram analisados 26.990 registros, sendo 18.834 (69,8%) do sexo masculino, com idade mediana de 61 (17) anos. Na análise multivariada, as principais variáveis relacionadas ao desfecho óbito com seus respectivos odds ratio e intervalos de confiança (IC) com nível de significância de 95% foram a idade avançada 70 - 79 anos (2,46; 1,64 - 3,79) e ≥ 80 anos (3,68; 2,38 - 5,81), p<0,001, classificação de Killip II (2,71; 1,92 - 3,83), Killip III (8,14; 5,67 - 11,64), Killip IV (19,83; 14,85 - 26,69), p<0,001, disfunção global acentuada do ventrículo esquerdo (VE) (3,63; 2,39 - 5,68), p<0,001 e ocorrência de infarto após a intervenção (5,01; 2,57- 9,46), p<0,001. O principal fator protetor foi o fluxo TIMI III pós-intervenção (0,18; 0,13 - 0,24), p<0,001, seguido do TIMI II (0,59; 0,41 - 0,86), p=0,005, sexo masculino (0,79; 0,64 - 0,98), p= 0,032, dislipidemia (0,69; 0,59 - 0,85), p<0,001 e número de lesões tratadas (0,86; 0,9 - 0,94), p<0,001. Conclusão Os preditores de mortalidade nos pacientes submetidos a ATC foram: classificação de Killip, reinfarto, idade, disfunção global acentuada do VE, sexo feminino e fluxo TIMI 0/I pós-intervenção.

Abstract Background Identification of high-risk patients undergoing primary angioplasty (PCI) is essential. Objective Identify factors related to the causes of death in PCI patients. Methods This work consisted of a multicenter case-control study using a Brazilian registry of cardiovascular interventions as the data source. The association between each variable and death was assessed using a binary logistic regression model, p <0.05 was considered significant. Results A total of 26,990 records were analyzed, of which 18,834 (69.8%) were male patients, with a median age of 61 (±17) years. In the multivariate analysis, the main variables related to the causes of death with their respective odds ratios and 95%confidence intervals (CI) were advanced age, 70-79 years (2.46; 1.64-3.79) and ≥ 80 years (3.69; 2.38-5.81), p<0.001; the classification of Killip II (2.71; 1.92-3.83), Killip III (8.14; 5.67-11.64), and Killip IV (19.83; 14.85-26.69), p<0.001; accentuated global dysfunction (3.63; 2,39-5.68), p<0.001; and the occurrence of infarction after intervention (5.01; 2.57-9.46), p<0.001. The main protective factor was the post-intervention thrombolysis in myocardial infarction (TIMI) III flow (0.18; 0.13-0.24), p<0.001, followed by TIMI II (0.59; 0.41 -0.86), p=0.005, and male (0.79; 0.64-0.98), p = 0.032; dyslipidemia (0.69; 0.59-0.85), p<0.001; and number of lesions treated (0.86; 0.9-0.94), p<0.001. Conclusion The predictors of mortality in patients undergoing PCI were Killip's classification, reinfarction, advanced age, severe left ventricular dysfunction, female gender, and post-intervention TIMI 0 / I flow.

Otimização da Terapia de Reperfusão no Infarto Agudo do Miocárdio com Supradesnível do Segmento ST por Meio de Telemedicina Baseada no WhatsApp® / Reperfusion Therapy Optimization in Acute Myocardial Infarction with ST-Segment Elevation using WhatsApp®-Based Telemedicine

Resumo Fundamento Cerca de 40% dos pacientes com infarto agudo do miocárdio com supradesnível do segmento ST (IAMCSST) no Brasil não recebem terapia de reperfusão. Objetivo A utilização de uma rede de telemedicina baseada no WhatsApp® poderia aumentar a porcentagem de pacientes que recebem terapia de reperfusão. Métodos Estudo transversal do tipo antes e depois da organização de uma rede de telemedicina para envio e análise do eletrocardiograma através do WhatsApp® dos pacientes suspeitos de IAMCSST oriundos dos 25 municípios integrantes do Departamento Regional de Saúde de Ribeirão Preto (DRS−XIII), para hospital terciário que poderia autorizar a transferência imediata do paciente utilizando o mesmo sistema. O desfechos analisados foram a porcentagem de pacientes que receberam terapia de reperfusão e a taxa de mortalidade intra-hospitalar. Considerou-se valor de p <0,05 como estatisticamente significativo. Resultados Foram comparados 82 pacientes antes desta rede (1º de fevereiro de 2016 a 31 de janeiro de 2018) com 196 pacientes depois da implantação da mesma (1º de fevereiro de 2018 a 31 de janeiro de 2020). Após a implantação da rede, houve aumento significativo da proporção de pacientes que receberam terapia de reperfusão (60% vs. 92%), risco relativo (RR): 1,594 [intervalo de confiança (IC) 95% 1,331 - 1,909], p <0,0001 e redução da mortalidade intra-hospitalar (13,4% vs. 5,6%), RR: 0,418 [IC 95% 0,189 - 0,927], p = 0,028. Conclusão Rede de telemedicina baseada no WhatsApp® associou-se a aumento da porcentagem de pacientes com IAMCSST que receberam terapia de reperfusão e a redução na mortalidade intra-hospitalar.

Abstract Background About 40% of patients with ST-segment elevation myocardial infarction (STEMI) in Brazil do not receive reperfusion therapy. Objective The use of a telemedicine network based on WhatsApp® could increase the percentage of patients receiving reperfusion therapy. Methods A cross-sectional study analyzed outcomes before and after the organization of a telemedicine network to send the electrocardiogram via WhatsApp® of patients suspected of STEMI from 25 municipalities that are members of the Regional Health Department of Ribeirão Preto (DRS−XIII) to a tertiary hospital, which could authorize immediate patient transfer using the same system. The analyzed outcomes included the percentage of patients who received reperfusion therapy and the in-hospital mortality rate. A p value < 0.05 was considered statistically significant. Results The study compared 82 patients before (February 1, 2016 to January 31, 2018) with 196 patients after this network implementation (February 1, 2018 to January 31, 2020). After implementing this network, there was a significant increase in the proportion of patients who received reperfusion therapy (60% vs. 92%), relative risk (RR): 1.594 [95% confidence interval (CI) 1.331 - 1.909], p < 0.0001 and decrease in the in-hospital mortality rate (13.4% vs. 5.6%), RR: 0.418 [95%CI 0.189 - 0.927], p = 0.028. Conclusion The use of WhatsApp®-based telemedicine has led to an increase in the percentage of patients with STEMI who received reperfusion therapy and a decrease in the in-hospital mortality rate.

Effect of curcumin on acute chronic kidney disease due to ischemia-reperfusion syndrome / Efecto de la curcumina en la enfermedad renal crónica agravada por el síndrome de isquemia-reperfusión / Efeito da curcumina na doença renal crônica agudizada pela síndrome isquemia-reperfusão

ABSTRACT Objective: To evaluate the effect of curcumin on renal function, hemodynamics, and renal oxidative profile of rats with chronic kidney disease (CKD) subjected to renal ischemia-reperfusion injury (IRI). Methods: Wistar rats, 250-300 g, distributed in four groups: Sham (n = 5), CKD simulation; CKD (n = 5), 5/6 renal ablation for CKD induction; CKD + IRI (n = 5), CKD and renal pedicle clamping for 30 minutes; and CKD + IRI+curcumin (n = 5), CKD + IRI, curcumin administration 30 mg/kg/day, orally, for 10 days. Renal function (inulin clearance, urine flow, plasma creatinine), hemodynamics (blood pressure), and oxidative profile (peroxides, TBARS, and urine nitrate, non-protein soluble thiols in renal tissue) were evaluated. Results: The CKD + IRI + curcumin group showed increased inulin clearance and reduced plasma creatinine, decreased RVR and increased RBF, decreased oxidative metabolites in urine and increased thiols in renal tissue when compared with the CKD + IRI group. Conclusion: The treatment with curcumin preserved renal function and hemodynamics of animals with acute CKD, improving oxidative profile, with reduction of oxidants and preservation of antioxidant reserve.

RESUMEN Objetivo: Evaluar el efecto de la curcumina sobre la función renal, hemodinámica y el perfil oxidativo renal en ratas con enfermedad renal crónica (ERC) sometidas a isquemia-reperfusión renal (I/R). Métodos: Ratas Wistar, entre 250-300 g, divididas en cuatro grupos: Sham (n = 5), simulación de ERC; ERC (n = 5), ablación de 5/6 de los riñones para inducción de ERC; ERC + I/R (n = 5), ERC y pinzamiento del pedículo renal durante 30 minutos; y ERC + I/R + curcumina (n = 5) y ERC + I/R, administración de curcumina 30 mg/kg/día, vía oral, durante 10 días. Se evaluaron la función renal (clearance de inulina, flujo urinario, creatinina plasmática), hemodinámica (presión arterial) y el perfil oxidativo (peróxidos, TBARS y nitrato urinario, tioles solubles no proteicos en tejido renal). Resultados: El grupo ERC + I/R + curcumina tuvo un aumento en el clearance de inulina y disminución de creatinina plasmática, disminución de la RVR y aumento del FSR, disminución de metabolitos oxidativos en orina y aumento de tioles en el tejido renal en comparación con el grupo ERC + I/R. Conclusión: El tratamiento con curcumina preservó la función renal y la hemodinámica de los animales con ERC agravada, promoviendo una mejora en el perfil oxidativo, con reducción de oxidantes y preservación de la reserva antioxidante.

RESUMO Objetivo: Avaliar o efeito da curcumina na função renal, hemodinâmica e perfil oxidativo renal de ratos com doença renal crônica (DRC) submetidos a isquemia-reperfusão renal (I/R). Métodos: Ratos Wistar, 250-300 g, distribuídos em quatro grupos: Sham (n = 5), simulação da DRC; DRC (n = 5), ablação de 5/6 dos rins para indução de DRC; DRC + I/R (n = 5), DRC e clampeamento do pedículo renal por 30 minutos; DRC + I/R + curcumina (n = 5) e DRC + I/R, administração de curcumina 30 mg/kg/dia, via oral, por 10 dias. Foram avaliadas a função renal (clearance de inulina, fluxo urinário, creatinina plasmática), hemodinâmica (pressão arterial) e perfil oxidativo (peróxidos, TBARS e nitrato urinário, tióis solúveis não proteicos no tecido renal). Resultados: O grupo DRC + I/R + curcumina apresentou elevação do clearance de inulina e redução da creatinina plasmática, diminuição da RVR e aumento do FSR, diminuição de metabólitos oxidativos na urina e aumento dos tióis no tecido renal quando comparado ao grupo DRC + I/R. Conclusão: O tratamento com curcumina preservou a função e hemodinâmica renal dos animais com DRC agudizada, promovendo melhora no perfil oxidativo, com redução de oxidantes e preservação de reserva antioxidante.

Evaluation of nefrotoxicity by tacrolimus and micophenolate mofetil associated with kidney ischemia and reperfusion: experimental study in rats / Avaliação da nefrotoxicidade pelo tacrolimus e micofenolato mofetil associados à isquemia e reperfusão renal: estudo experimental em ratos

ABSTRACT Objective: to evaluate the renal toxicity caused by tacrolimus and mycophenolate mofetil (MMF) in a single kidney ischemia and reperfusion model. Method: experimental study using Wistar rats, submitted to right nephrectomy and left renal ischemia for 20 minutes, separated into groups in the postoperative period (PO): 1) Control (nonoperated); 2) Sham (operated, without PO drug); 3) TAC0.1, TAC1 and TAC10, tacrolimus administered PO at doses of 0.1mg/kg, 1mg/kg and 10mg/kg via gavage, respectively; 4) MMF, administered mycophenolate mofetil 20mg/kg; 5) MMF/TAC1 and MMF/TAC0.5, with an association of mycophenolate mofetil 20mg/kg and tacrolimus 1mg/kg and 0.5mg/kg, respectively. They were killed on the 14th PO and the kidney was removed for tissue oxidative stress analysis, by the dosage of reduced glutathione (GSH), lipoperoxidation (LPO) and protein carbonylation (PCO), and histological analysis by glomerular stereology (Glomerular volume density, Numerical density glomerular and mean glomerular volume). Renal function was evaluated by the measurement of serum creatinine and urea. Results: both drugs caused alterations in renal function, and the toxicity of tacrolimus was dose-dependent. Subacute toxicity did not show significant glomerular histological changes, and there was renal and compensatory glomerular hypertrophy in all groups except TAC10. Conclusion: Both drugs cause changes in renal function. Glomerular morphometry and stereology showed negative interference of immunosuppressants during compensatory glomerular hypertrophy.

RESUMO Objetivo: avaliar a toxicidade renal causada pelo tacrolimus e micofenolato mofetil (MMF) em um modelo de isquemia e reperfusão de rim único. Método: estudo experimental utilizando ratos Wistar, submetidos á nefrectomia direita e isquemia renal esquerda por 20 minutos, separados em grupos no pós- operatório (PO): 1) Controle (não operados); 2) Sham (operados, sem droga PO); 3) TAC0.1, TAC1 e TAC10, administrado tacrolimus no PO nas doses 0,1mg/kg, 1mg/kg e 10mg/kg via gavagem, respectivamentae; 4) MMF, administrado micofenolato mofetil 20mg/kg; 5) MMF/TAC1 e MMF/TAC0.5, com associação de micofenolato mofetil 20mg/kg e tacrolimus 1mg/kg e 0,5mg/kg, respectivamente. Foram mortos no 14º PO e retirado rim para análise do estresse oxidativo tecidual, pela dosagem de glutationa reduzida (GSH), lipoperoxidação (LPO) e carbonilação de proteínas (PCO), e análise histológica por estereologia glomerular (Densidade de volume glomerular, Densidade numérica glomerular e Volume glomerular médio). Foi avaliada função renal pela dosagem de creatinina e uréia séricas. Resultados: ambas drogas provocaram alteração na função renal, sendo a toxicidade do tacrolimus dosedependente. A toxicidade subaguda não mostrou alterações histológicas glomerulares significativas, sendo que houve hipertrofia renal e glomerular compensatória em todos os grupos exceto em TAC10. Conclusão: Ambas drogas provocam alteração na função renal. A morfometria e a estereologia glomerular mostraram interferência negativa dos imunossupressores durante a hipertrofia glomerular compensatória..

O Pré-Condicionamento com Dexmedetomidina Reduz a Lesão de Isquemia-Reperfusão do Miocárdio em Ratos, Inibindo a Via PERK / Dexmedetomidine Preconditioning Reduces Myocardial Ischemia-Reperfusion Injury in Rats by Inhibiting the PERK Pathway

Resumo Fundamento A cardiopatia isquêmica atraiu muito atenção devido às altas taxas de mortalidade, custos do tratamento e a crescente morbidade na população jovem. Estratégias de reperfusão reduziram a mortalidade. Porém, a reperfusão pode levar à morte do cardiomiócito e subsequente dano irreversível ao miocárdio. No momento, não há um tratamento eficiente e direcionado para a lesão de isquemia-reperfusão (I/R). Objetivos Avaliar se a dexmedetomidina (DEX) tem efeito protetivo na I/R do miocárdio e explorar os possíveis mecanismos por trás dela. Métodos Corações de ratos foram perfundidos com o sistema de perfusão de Langendorff e aleatoriamente distribuídos em cinco grupos: grupo controle, perfundido com solução de Krebs-Henseleit (K-H) por 205 minutos sem isquemia; e quatro grupos de teste que foram submetidos a 40 minutos de isquemia global e 120 minutos de reperfusão. O Grupo DEX, o grupo ioimbina (IO) e o grupo DEX + IO foram perfundidos com DEX (10 nM), IO (1 μM) ou a combinação de DEX e IO antes da reperfusão, respectivamente. A hemodinâmica cardíaca, o tamanho do infarto do miocárdio e a histologia do miocárdio foram avaliados. A expressão da proteína-78 regulada pela glicose (GRP78), a proteína quinase do retículo endoplasmático (PERK), a PERK fosforilada, o fator de iniciação eucariótico 2α (eIF2α), eIF2α fosforilado, o fator de transcrição 4 (TCF-4) e a proteína homóloga à proteína ligadora do acentuador CCAAT (CHOP) foram avaliados. P< 0,05 foi considerado para indicar a diferença estatisticamente significativa. Resultados O pré-condicionamento com DEX melhorou a função cardíaca nos corações com I/R, reduziu o infarto do miocárdio, a apoptose do miocárdio e a expressão de GRP78, p-PERK, eIF2α, p-eIF2α, TCF-4 e CHOP. Conclusões O pré-tratamento com DEX reduziu a lesão de I/R no miocárdio ao suprimir a apoptose, o que foi induzido pela via PERK.

Abstract Background Ischemic heart disease has attracted much attention due to its high mortality rates, treatment costs and the increasing morbidity in the young population. Strategies for reperfusion have reduced mortality. However, reperfusion can lead to cardiomyocyte death and subsequent irreversible myocardial damage. At present, the timely and targeted treatment of ischemia-reperfusion (I/R) injury is often lacking. Objectives To evaluate if dexmedetomidine (DEX) has a protective effect in myocardiual I/R and explore the possible mechanism behind it. Methods Rat hearts were perfused with a Langendorff perfusion system, and randomly assigned to five groups: control group, perfused with Krebs-Henseleit (K-H) solution for 205 minutes without ischemia; and four test groups that underwent 40 minutes of global ischemia and 120 min of reperfusion. The DEX group, the yohimbine (YOH) group and the DEX + YOH group were perfused with DEX (10 nM), YOH (1 μM) or the combination of DEX and YOH prior to reperfusion, respectively. Cardiac hemodynamics, myocardial infarct size, and myocardial histology were evaluated. The expression of glucose-related protein 78 (GRP78), protein kinase R-like ER kinase (PERK), phosphorylated PERK, eukaryotic initiation factor 2α (eIF2α), phosphorylated eIF2α, activating transcription factor 4 (ATF4), and CCAAT/enhancer-binding protein homologous protein (CHOP) were assessed. P<0.05 was considered to indicate a statistically significant difference. Results DEX preconditioning improved the cardiac function of I/R hearts, reduced myocardial infarction, myocardial apoptosis, and the expression of GRP78, p-PERK, eIF2α, p-eIF2α, ATF4 and CHOP. Conclusions DEX pretreatment reduced myocardial I/R injury by suppressing apoptosis, which was induced by the PERK pathway.

Naringin and trimetazidine improve baroreflex sensitivity and nucleus tractus solitarius electrical activity in renal ischemia-reperfusion injury / Naringin and trimetazidine improve baroreflex sensitivity and nucleus tractus solitarius electrical activity in renal ischemia-reperfusion injury

Resumo Fundamento: O núcleo do trato solitário (NTS) é uma área do cérebro que desempenha um papel fundamental na regulação renal e cardiovascular através dos impulsos dos barorreceptores. Objetivos: O objetivo deste estudo foi avaliar o efeito da Naringina (NAR) e trimetazidina (TMZ), isoladamente e combinadas, na atividade elétrica do NTS e na sensibilidade barorreflexa (SBR) na lesão de isquemia e reperfusão (I/R) renal. Métodos: Foram utilizados quarenta ratos machos Sprague-Dawley (200-250 g), alocados em 5 grupos com 8 ratos cada. Grupos: 1) Sham; 2) I/R; 3) TMZ 5 mg/kg; 4) NAR 100 mg/kg; e 5) TMZ5 + NAR100. A veia femoral esquerda foi canulada para infundir a solução salina ou droga e avaliar a SBR. A I/R foi induzida por oclusão dos pedículos renais por 45 min, seguida de reperfusão de 4 horas. O eletroencefalograma local do NTS foi registrado antes, durante a isquemia e durante a reperfusão. A fenilefrina foi injetada por via intravenosa para avaliar a SBR ao final do tempo de reperfusão. Os dados foram analisados por ANOVA de duas vias com medidas repetidas seguida pelo teste post hoc de Tukey. Um valor de p<0,05 foi considerado como significativo. Resultados: As ondas elétricas do NTS não se alteraram durante o tempo de isquemia, mas diminuíram significativamente durante todos os tempos de reperfusão. A atividade elétrica do NTS e a SBR foram reduzidas drasticamente em ratos com lesão I/R; no entanto, a administração de NAR e TMZ, isoladamente e combinadas, melhorou significativamente essas alterações em ratos com lesão I/R. Conclusões: Os resultados mostraram que a lesão de I/R leva à redução da atividade elétrica da SBR e do NTS, e pode haver uma ligação entre a I/R e a diminuição da SBR. Além disso, a NAR e a TMZ são agentes promissores para tratar complicações de I/R.

Abstract Background: Nucleus tractus solitarius (NTS) is a brain area that plays a key role in kidney and cardiovascular regulation via baroreceptors impulses. Objectives: The aim of this study was to evaluate the effect of naringin (NAR) and trimetazidine (TMZ) alone and their combination on NTS electrical activity and baroreceptor sensitivity (BRS) in renal ischemia- reperfusion (I/R) injury. Methods: Forty male Sprague-Dawley rats (200- 250 g) were allocated into 5 groups with 8 in each. 1) Sham; 2) I/R; 3) TMZ 5 mg/kg; 4) NAR 100 mg/kg; and 5) TMZ5+ NAR100. The left femoral vein was cannulated to infuse saline solution or drug and the BRS was evaluated. I/R was induced by occlusion of renal pedicles for 45 min, followed by 4 hours of reperfusion. The NTS local electroencephalogram (EEG) was recorded before, during ischemia and throughout the reperfusion. Phenylephrine was injected intravenously to evaluate BRS at the end of reperfusion time. The data were analyzed by two-way repeated measurement ANOVA followed by Tukey's post hoc test. A p-value <0.05 was considered significant. Results: NTS electrical waves did not change during ischemia time, while they significantly decreased during the entire reperfusion time. NTS electrical activity and BRS dramatically reduced in rats with I/R injury; however, administration of NAR, TMZ alone or their combination significantly improved these changes in rats with I/R injury. Conclusions: The results showed that I/R injury leads to reduced BRS and NTS electrical activity and there may be an association between I/R and decreased BRS. In addition, NAR and TMZ are promising agents to treat I/R complications.