Prenatal alcohol exposure may cause cardiac development defects, however, the underlying mechanisms are not yet clear. In the present study we have investigated the roles of histone modification by curcumin on alcohol induced fetal cardiac abnormalities during the development. Q-PCR and Western blot results showed that alcohol exposure increased gene and active forms of caspase-3 and caspase-8, while decreased gene and protein of bcl-2. ChIP assay results showed that, alcohol exposure increased the acetylation of histone H3K9 near the promoter region of caspase-3 and caspase-8, and decreased the acetylation of histone H3K9 near the promoter region of bcl-2. TUNEL assay data revealed that alcohol exposure increased the apoptosis levels in the embryonic hearts. In vitro experiments demonstrated that curcumin treatment could reverse the up-regulation of active forms of caspase-3 and caspase-8, and down-regulation of bcl-2 induced by alcohol treatment. In addition, curcumin also corrected the high level of histone H3K9 acetylation induced by alcohol. Moreover, the high apoptosis level induced by alcohol was reversed after curcumin treatment in cardiac cells. These findings indicate that histone modification may play an important role in mediating alcohol induced fetal cardiac apoptosis, possibly through the up-regulation of H3K9 acetylation near the promoter regions of apoptotic genes. Curcumin treatment may correct alcohol-mediated fetal cardiac apoptosis, suggesting that curcumin may play a protective role against alcohol abuse caused cardiac damage during pregnancy.
Bone marrow derived stem cells (BMSCs) have the potential to differentiate into cardiomyocytes, but the rate of differentiation is low and the mechanism of differentiation is unclear completely. Here, we aimed to investigate the role of miR1-2 in differentiation of mouse BMSCs into cardiomyocyte-like cells and reveal the involved signaling pathways in the procedure. Mouse BMSCs were treated with miR1-2 and 5-azacytine (5-aza). The expression of cardiac cell markers: NKx2.5, cTnI and GATA4 in BMSCs were examined by qPCR. The apoptosis rate was detected by flow cytometry and the activity of the Wnt/β-catenin signaling pathway was evaluated by measuring the upstream protein of this signaling pathway. After over-expression of miR1-2 in mouse BMSCs, the apoptosis rate was significantly lower than the 5-aza group, while the expressions of cardiac-specific genes: such as Nkx2.5, cTnI and GATA4 were significantly increased compared to the control group and the 5-aza group. Meanwhile, over-expression of miR1-2 in mouse BMSCs enhanced the expression of wnt11, JNK, β-catenin and TCF in the Wnt/β-catenin signaling pathway. Use of LGK-974, an inhibitor of Wnt/β-catenin signaling pathway, significantly reduced the expression of cardiac-specific genes and partially blocked the role of the miR1-2. Over-expression of miR1-2 in mouse BMSCs can induce them toward promoted cardiomyocyte differentiation via the activation of the Wnt/β-catenin signaling pathway. Compared to 5-aza, miR1-2 can induce differentiation of BMSCs into cardiomyocytes more effectively with a less cytotoxicity.
Our previous studies have demonstrated that Ca2+ desensitizing catechin could correct diastolic dysfunction in experimental animals with restrictive cardiomyopathy. In this study, it is aimed to assess the effects of green tea extract catechin on cardiac function and other clinical features in pediatric patients with cardiomyopathies. Twelve pediatric cardiomyopathy patients with diastolic dysfunction were enrolled for the study. Echocardiography, ECG, and laboratory tests were performed before and after the catechin administration for 12 months. Comparison has been made in these patients before and after the treatment with catechin. Next Generation Sequencing was conducted to find out the potential causative gene variants in all patients. A significant decrease of isovolumetric relaxation time (115 ± 46 vs 100 ± 42 ms, P = 0.047 at 6 months; 115 ± 46 vs 94 ± 30 ms, P = 0.033 at 12 months), an increase of left ventricle end diastolic volume (40 ± 28 vs 53 ± 28 ml, P = 0.028 at 6 months; 40 ± 28 vs 48 ± 33 ml, P = 0.011 at 12 months) and stroke volume (25 ± 16 vs 32 ± 17 ml, P = 0.022 at 6 months; 25 ± 16 vs 30 ± 17 ml, P = 0.021 at 12 months) were observed with echocardiography in these patients 6-month after the treatment with catechin. Ejection fraction, left ventricular wall thickness, biatrial dimension remained unchanged. No significant side effects were observed in the patients tested. This study indicates that Ca2+ desensitizing green tea extract catechin, is helpful in correcting the impaired relaxation in pediatric cardiomyopathy patients with diastolic dysfunction.
Restrictive cardiomyopathy (RCM) is a rare, fatal disorder that rapidly progresses in children. TNNI3 mutations represent the most common genetic cause. Although cTnI mutations are known to increase myofilament calcium sensitivity and impair diastolic function, this mechanism alone does not fully account for disease pathogenesis. Recent studies have revealed that the immune system plays an important role in cardiovascular diseases, however, its involvement in RCM remains unclear. Here, we generated a classic cTnIR193H mouse model using CRISPR/Cas9. Cardiac RNA-seq analysis indicated marked activation of innate immune pathways. moreover, biotin-mediated proximity labeling combined with quantitative mass spectrometry identified differential interactors of the cTnIR193H mutant, with Irgm1 emerging as the most significantly altered immune-related protein. Notably, the cTnIR193H mutation enhances binding to Irgm1 without affecting its expression, thereby indirectly inhibiting its normal function. This aberrant interaction activates the cGAS-STING pathway and elicits a type I interferon response in the hearts of RCM mice. Furthermore, treatment with the STING inhibitor C176 partially restored diastolic function and significantly alleviated cardiac fibrosis. Taken together, this study reveals for the first time that immune mechanisms play a crucial role in RCM pathogenesis and provides a potential therapeutic target for RCM treatment from an immunological perspective.