Neural cell adhesion molecule expression in dilated cardiomyopathy is associated with intramyocardial inflammation and hypertrophy

The effects of extracellular vesicles derived from Krüppel-Like Factor 2 overexpressing endothelial cells on the regulation of cardiac inflammation in the dilated cardiomyopathy

BACKGROUND

Dilated cardiomyopathy (DCM) is one of the common causes of heart failure. Myocardial injury triggers an inflammatory response and recruits immune cells into the heart. High expression of Krüppel-like factor 2 (KLF2) in endothelial cells (ECs) potentially exerts an anti-inflammatory effect. However, the role of extracellular vesicles (EVs) from KLF2-overexpressing ECs (KLF2-EVs) in DCM remains unclear.

METHODS AND RESULTS

EVs were separated from the supernatant of KLF2-overexpressing ECs by gradient centrifugation. Mice were repeatedly administered low-dose doxorubicin (DOX) and then received KLF2-EVs through an intravenous injection. Treatment with KLF2-EVs prevented doxorubicin-induced left ventricular dysfunction and reduced the recruitment of Ly6^high Mo/Mø in the myocardium. We used flow cytometry to detect Ly6^high monocytes in bone marrow and spleen tissues and to elucidate the mechanisms underlying this beneficial effect. KLF2-EVs increased the retention of Ly6C^high monocytes in the bone marrow but not in the spleen tissue. KLF2-EVs also significantly downregulated C-C chemokine receptor 2 (CCR2) protein expression in cells from the bone marrow.

CONCLUSIONS

EVs derived from KLF2-overexpressing ECs reduced cardiac inflammation and ameliorated left ventricular dysfunction in DCM mice by targeting the CCR2 protein to inhibit Ly6C^high monocyte mobilization from the bone marrow.

Quercetin Efficiently Alleviates TNF-α-Stimulated Injury by Signal Transducer and Activator of Transcription 1 and Mitogen-Activated Protein Kinase Pathway in H9c2 Cells: A Protective Role of Quercetin in Myocarditis

ABSTRACT

This study aimed to evaluate the protective effect of quercetin and its in-depth mechanism in TNF-α-stimulated cardiomyocytes. The differential expression of TNF-alpha (TNF-α) and signal transducer and activator of transcription 1 (STAT1) was analyzed based on the GEO database. H9c2 cells were stimulated with TNF-α to simulate myocarditis. Cell counting kit-8 assay and flow cytometry assay were performed to detect the cell viability and apoptosis. ELISA was used to measure the levels of proinflammatory cytokines (IL-6 and IL-17A) and anti-inflammatory cytokine (IL-10). STAT1 expression was downregulated by transfection with si-STAT1, and its expression was detected using quantitative real-time polymerase chain reaction and Western blot. Western blot was also performed to assess the expression of the mitogen-activated protein kinase (MAPK) pathway-related factors. In this article, TNF-α was highly expressed in patients with myocarditis, and TNF-α (20 μg/mL) declined the viability of H9c2 cells. Quercetin pretreatment partially alleviated the decrease of cell viability, the increase of apoptosis, and the release of inflammatory cytokines (IL-10, IL-6, and IL-17A) induced by TNF-α. In addition, TNF-α increased STAT1 expression, but quercetin prevented the TNF-α-increased STAT1 level. Remarkably, knockdown of STAT1 enhanced the protective effect of quercetin on TNF-α-injured H9c2 cells. Moreover, quercetin restrained the TNF-α-induced activation of the MAPK pathway. Also, the inhibitory effect of quercetin on the pathway was aggravated by STAT1 lacking. In summing, quercetin plays a protective role in TNF-α-stimulated H9c2 cell injury, which may be related to the regulation of STAT1 and MAPK pathway.

Relationship of elevated neural cell adhesion molecule 1 with interleukin-10 and disease severity in bipolar disorder

Neural plasticity and inflammation are known to play a role in the pathogenesis of Bipolar disorder. The data related to markers of neural plasticity in bipolar disorder are limited. The objective of the study was to assess the levels of neural cell adhesion molecule 1 (NCAM 1) and interleukin-10 and their association with disease severity in bipolar disorder. 40 bipolar disorder I patients with acute manic symptoms and 40 age matched controls were enrolled in the study. Neural cell adhesion molecule 1 and interleukin-10 (IL-10) levels were assessed in both the groups. NCAM 1 and interleukin-10 levels were significantly increased in bipolar disorder when compared with controls. There was significant positive correlation of Young Mania Rating score with NCAM 1 (r = 0.538, p = < 0.001) in patients with BD. Multi variate analysis revealed that IL-10 (p = 0.021) was lower in controls by 0.012 ng/L and NCAM 1(p = 0.048) was lower in controls by 0.002 ng/L compared to BD cases and this difference was statistically significant. Based on the findings we conclude that neural cell adhesion molecule 1 is increased and associated with disease severity in bipolar disorder.