ABSTRACT Purpose: The epithelial–mesenchymal transition of human lens epithelial cells plays a role in posterior capsule opacification, a fibrotic process that leads to a common type of cataract. Hyaluronic acid has been implicated in this fibrosis. Studies have investigated the role of transforming growth factor (TGF)-β2 in epithelial–mesenchymal transition. However, the role of TGF-β2 in hyaluronic acid-mediated fibrosis of lens epithelial cell remains unknown. We here examined the role of TGF-β2 in the hyaluronic acid-mediated epithelial–mesenchymal transition of lens epithelial cells. Methods: Cultured human lens epithelial cells (HLEB3) were infected with CD44-siRNA by using the Lipofectamine 3000 transfection reagent. The CCK-8 kit was used to measure cell viability, and the scratch assay was used to determine cell migration. Cell oxidative stress was analyzed in a dichloro-dihydro-fluorescein diacetate assay and by using a flow cytometer. The TGF-β2 level in HLEB3 cells was examined through immunohistochemical staining. The TGF-β2 protein level was determined through western blotting. mRNA expression levels were determined through quantitative real-time polymerase chain reaction. Results: Treatment with hyaluronic acid (1.0 μM, 24 h) increased the epithelial–mesenchymal transition of HLEB3 cells. The increase in TGF-β2 levels corresponded to an increase in CD44 levels in the culture medium. However, blocking the CD44 function significantly reduced the TGF-β2-mediated epithelial–mesenchymal transition response of HLEB3 cells. Conclusions: Our study showed that both CD44 and TGF-β2 are critical contributors to the hyaluronic acid-mediated epithelial-mesenchymal transition of lens epithelial cells, and that TGF-β2 in epithelial-mesenchymal transition is regulated by CD44. These results suggest that CD44 could be used as a target for preventing hyaluronic acid-induced posterior capsule opacification. Our findings suggest that CD44/TGF-β2 is crucial for the hyaluronic acid-induced epithelial-mesenchymal transition of lens epithelial cells. Purpose epithelialmesenchymal mesenchymal opacification cataract TGFβ2 TGFβ TGF β2 β (TGF)-β However TGF-β acidmediated mediated unknown Methods HLEB (HLEB3 CD44siRNA CDsiRNA siRNA CD 300 reagent CCK8 CCK 8 CCK- viability migration dichlorodihydrofluorescein dichloro dihydro fluorescein cytometer staining blotting realtime real time reaction Results 1.0 10 1 0 (1. μM 2 h CD4 medium TGFβ2mediated TGFβmediated Conclusions acidinduced induced CD44/TGFβ2 CD44TGFβ2 CDTGFβ CD44/TGF CD44/TGF-β (HLEB 30 1. (1 CD44/TGFβ CD44TGFβ CD44TGF CDTGF 3 (

Resumo Fundamento A doxorrubicina está associada à cardiotoxicidade e à morbidade cardíaca tardia. O heme está relacionado ao stress oxidativo celular. Entretanto, sua regulação específica em cardiomiócitos sob os efeitos de doxorrubicina ainda não foi documentada. Objetivo Nosso objetivo é avaliar as alterações de enzimas limitantes de velocidade no caminho metabólico do heme sob o efeito de doxorrubicina. Métodos Cardiomiócitos H9c2 com doxorrubicina em concentrações diferentes (1, 2, 5, 10μM respectivamente). Os testes de PCR em tempo real e Western Blot foram usados para determinar a expressão de proteína e mRNA para quatro enzimas cruciais (ALAS1, ALAS2, HOX-1, e HOX-2) que regulam o metabolismo do heme celular, e os níveis de heme foram detectados por ELISA. Um p<0,01 foi considerado significativo. Resultados Observamos um padrão com alteração dependendo da dose nos níveis de heme nas células H9c2 com o nível mais alto na concentração de 5μM de doxorrubicina, o que ocorreu sincronicamente com o nível mais alto de regulação para cima de ALAS1, bem como as enzimas degenerativas HOX-1 e HOX-2 na expressão de proteína e mRNA. Em contraste, observamos que a ALAS2 foi regulada para baixo gradualmente, inversamente proporcional às concentrações de doxorrubicina. Conclusão O aumento da expressão de ALAS1 pode ter um papel na elevação do nível do heme quando o cardiomiócito H9c2 for exposto à doxorrubicina, e pode ser um alvo terapêutico para a toxicidade miocárdica induzida por doxorrubicina. (Arq Bras Cardiol. 2021; 116(2):315-322)

Abstract Background Doxorubicin is associated with cardiotoxicity and late cardiac morbidity. Heme is related to cellular oxidative stress. However, its specific regulation in cardiomyocytes under doxorubicin effects has not yet been documented. Objective This study seeks to evaluate the changing profiles of rate-limiting enzymes in the heme metabolism pathway under the effect of doxorubicin. Methods H9c2 cardiomyocytes were incubated with doxorubicin at different concentrations (1,2,5,10μM respectively). The real-time PCR and Western Blot were used to determine the mRNA and protein expression for four pivotal enzymes (ALAS1, ALAS2, HOX-1, and HOX-2) regulating cellular heme metabolism, as well as the levels of heme were detected by ELISA. p<0.01 was considered significant. Results This study observed a dose-dependent changing pattern in heme levels in H9c2 cells with the highest level at the 5μM concentration for doxorubicin, which occurred synchronously with the highest upregulation level of ALAS1, as well as the degradative enzymes, HOX-1, and HOX-2 in mRNA and protein expression. By contrast, ALAS2, contrary to the increasing concentrations of doxorubicin, was found to be progressively down-regulated. Conclusion The increase in ALAS1 expression may play a potential role in the heme level elevation when H9c2 cardiomyocyte was exposed to doxorubicin and may be a potential therapeutic target for doxorubicin-induced myocardial toxicity. (Arq Bras Cardiol. 2021; 116(2):315-322)

Resumo Fundamento: A carga trombótica intracoronária durante a intervenção coronária percutânea primária em pacientes com Infarto com Supradesnivelamento do Segmento ST (STEMI) pode levar a resultados negativos.Os monócitos foram descritos para desempenhar um papel importante nos distúrbios trombóticos. Objetivos: Este estudo investigou a relação entre a contagem de monócitos no momento da internação e a carga trombótica angiográfica intracoronária em pacientes submetidos à intervenção coronária percutânea primária (ICPP). Métodos: Um total de 273 pacientes com STEMI agudo submetidos à ICPP participaram. Os pacientes se dividiram em dois grupos de acordo com o grau trombótico na trombólise do infarto do miocárdio (TIMI): grupo baixa carga trombótica, com graus de 0-2, e grupo alta carga trombótica, com graus de 3-4. A contagem de monócitos e outros parâmetros laboratoriais foram medidos na internação antes da ICPP. Consideramos o valor de p < 0,05 significativo. Resultados: Havia 95 pacientes (34,8%) no grupo alta carga trombótica, e 178 pacientes (65,2%) no grupo baixa carga trombótica. Pacientes com alta carga trombótica apresentaram contagem de monócitos no momento da internação mais alta (0,61 ± 0,29×109/L vs. 0,53 ± 0,24×109/L, p = 0,021). Na análise multivariada, a contagem de monócitos foi o indicador independente da alta carga trombótica angiográfica (odds ratio 3,107, intervalo de confiança de 95% [IC] 1,199-7,052, p = 0,020). Para a previsão da alta carga trombótica angiográfica, a contagem de monócitos na internação tinha ponto de corte de 0,48×109/L, chegou a 0.59 ROC-AUC (71,9% sensibilidade, 46,9% especificidade). Conclusões: a contagem de monócitos na internação foi um indicador clínico independente da alta carga trombótica em pacientes com STEMI submetidos à ICPP. Nossos achados sugerem que a contagem de monócitos na internação pode estar disponível para a estratificação de risco precoce da alta carga trombótica em pacientes com STEMI agudo, e podem levar à otimização da terapia antitrombótica para melhorar os resultados da ICPP.

Abstract Background: The intracoronary high-thrombus burden during the primary percutaneous coronary intervention in patients with ST-elevation myocardial infarction (STEMI) can lead to poor outcomes. Monocytes have been described to play an important role in thrombotic disorders. Objectives: This study aimed to investigate the relationship between admission monocyte count and angiographic intracoronary thrombus burden in patients receiving primary percutaneous coronary intervention (PPCI). Methods: A total of 273 patients with acute STEMI who underwent PPCI were enrolled. The patients were divided into two groups according to the thrombolysis in myocardial infarction (TIMI) thrombus grade: low-thrombus burden group with a grade of 0-2 and high-thrombus burden group with a grade of 3-4. The monocyte count and other laboratory parameters were measured on admission before PPCI. P-value < 0.05 was considered significant. Results: There were 95 patients (34.8%) in the high-thrombus burden group, and 178 patients (65.2%) in the low-thrombus burden group. Patients with high-thrombus burden had significantly higher admission monocyte count (0.61 ± 0.29×109/L vs. 0.53 ± 0.24×109/L, p = 0.021). In multivariate analysis, monocyte count was the independent predictor of angiographic high-thrombus burden (odds ratio 3.107, 95% confidence interval [CI] 1.199-7.052, p = 0.020). For the prediction of angiographic high-thrombus burden, admission monocyte count at a cut-off value of 0.48×109/L yielded 0.59 ROC-AUC (71.9% sensitivity, 46.9% specificity). Conclusions: Monocyte count on admission was an independent clinical predictor of high-thrombus burden in patients with STEMI undergoing PPCI. Our findings suggest that admission monocyte count may be available for early risk stratification of high-thrombus burden in acute STEMI patients and might allow the optimization of antithrombotic therapy to improve the outcomes of PPCI.