Kawasaki disease (KD) is the most common cause of pediatric cardiac disease in developed countries, and can lead to permanent coronary artery damage and long term sequelae such as coronary artery aneurysms. Given the prevalence and severity of KD, further research is warranted on its pathophysiology. It is known that endothelial cell damage and inflammation are two essential processes resulting in the coronary endothelial dysfunction in KD. However, detailed mechanisms are largely unknown. In this study, we investigated the role of pyroptosis in the setting of KD, and hypothesized that pyroptosis may play a central role in its pathophysiology. In vivo experiments of patients with KD demonstrated that serum levels of pyroptosis-related proteins, including ASC, caspase-1, IL-1β, IL-18, GSDMD and lactic dehydrogenase (LDH), were significantly increased in KD compared with healthy controls (HCs). Moreover, western blot analysis showed that the expression of GSDMD and mature IL-1β was notably elevated in KD sera. In vitro, exposure of human umbilical vein endothelial cells (HUVECs) to KD sera-treated THP1 cells resulted in the activation of NLRP3 inflammasome and subsequent pyroptosis induction, as evidenced by elevated expression of caspase-1, GSDMD, cleaved p30 form of GSDMD, IL-1β and IL-18, and increased LDH release and TUNEL and propidium iodide (PI)-positive cells. Furthermore, our results showed that NLRP3-dependent endothelial cell pyroptosis was activated by HMGB1/RAGE/cathepsin B signaling. These findings were also recapitulated in a mouse model of KD induced by Candida albicans cell wall extracts (CAWS). Together, our findings suggest that endothelial cell pyroptosis may play a significant role in coronary endothelial damage in KD, providing novel evidence that further elucidates its pathophysiology.

Kawasaki disease (KD), an acute febrile systemic vasculitis in children, has become the leading cause of acquired heart disease in developed countries. Recently, the altered gut microbiota was found in KD patients during the acute phase. However, little is known about its characteristics and role in the pathogenesis of KD. In our study, an altered gut microbiota composition featured by the reduction in SCFAs-producing bacteria was demonstrated in the KD mouse model. Next, probiotic Clostridium butyricum (C. butyricum) and antibiotic cocktails were respectively employed to modulate gut microbiota. The use of C. butyricum significantly increased the abundance of SCFAs-producing bacteria and attenuated the coronary lesions with reduced inflammatory markers IL-1β and IL-6, but antibiotics depleting gut bacteria oppositely deteriorated the inflammation response. The gut leakage induced by dysbiosis to deteriorate the host’s inflammation was confirmed by the decreased intestinal barrier proteins Claudin-1, Jam-1, Occludin, and ZO-1, and increased plasma D-lactate level in KD mice. Mechanistically, SCFAs, the major beneficial metabolites of gut microbes to maintain the intestinal barrier integrity and inhibit inflammation, was also found decreased, especially butyrate, acetate and propionate, in KD mice by gas chromatography-mass spectrometry (GC-MS). Moreover, the reduced expression of SCFAs transporters, monocarboxylate transporter 1 (MCT-1) and sodium-dependent monocarboxylate transporter 1 (SMCT-1), was also shown in KD mice by western blot and RT-qPCR analyses. As expected, the decrease of fecal SCFAs production and barrier dysfunction were improved by oral C. butyricum treatment but was deteriorated by antibiotics. In vitro, butyrate, not acetate or propionate, increased the expression of phosphatase MKP-1 to dephosphorylate activated JNK, ERK1/2 and p38 MAPK against excessive inflammation in RAW264.7 macrophages. It suggests a new insight into probiotics and their metabolites supplements to treat KD.

Background: Transcatheter closure of perimembranous ventricular septal defects is one of the greatest challenges in interventional cardiology. Short- and midium-term follow-up data for large samples are limited. This report presents our experience with transcatheter closure of perimembranous ventricular septal defects using an occluder. Methods: Two hundred fifty-three patients included in the database of the Second Affiliated Hospital and Yuying Children’s Hospital from January 2011– December 2015 with transcatheter closure of perimembranous ventricular septal defects and discharged from follow-up. All patients were invited for clinical and transthoracic echocardiography, electrocardiogram, and thoracic radiography check-up. Results: Device implantation was successful in 252 of 253 patients (99.6%). The median age was 42 months (range 27–216 months). The median follow-up duration was 36 months (range 6–60 months). The mean defect diameter was 3.5 ± 1.4 mm and the mean size of the ventricular septal defect rim below the aortic valve was 3.7 ± 1.8 mm. The mean diameter of the devices used was 4 mm. Thirty-seven patients developed arrhythmia after the procedure and recovered within 24 months; four patients had hemolysis and four had moderate tricuspid valve regurgitation. No other serious adverse event occurred during the follow-up period. Conclusion: Transcatheter closure of perimembranous ventricular septal defects using an occluder is safe and effective in most patients.

Background: Kawasaki disease (KD) is a kind of vasculitis with unidentified etiology. Given that the current diagnosis and therapeutic strategy of KD are mainly dependent on clinical experiences, further research to explore its pathological mechanisms is warranted. Methods: Enzyme linked immunosorbent assay (ELISA) was used to measure the serum levels of SIGIRR, TLR4 and caspase-8. Western blotting was applied to determine protein levels, and flow cytometry was utilized to analyze cell apoptosis. Hematoxylin eosin (HE) staining and TUNEL staining were respectively used to observe coronary artery inflammation and DNA fragmentation. Results: In this study, we found the level of SIGIRR was downregulated in KD serum and KD serum-treated endothelial cells. However, the level of caspase-8 was increased in serum from KD patients compared with healthy control (HC). Therefore, we hypothesized that SIGIRR-caspase-8 signaling may play an essential role in KD pathophysiology. In vitro experiments demonstrated that endothelial cell apoptosis in the setting of KD was associated with caspase-8 activation, and SIGIRR overexpression alleviated endothelial cell apoptosis via inhibiting caspase-8 activation. These findings were also recapitulated in the Candida albicans cell wall extracts (CAWS)-induced KD mouse model. Conclusion: Our data suggest that endothelial cell apoptosis mediated by SIGIRR-caspase-8 signaling plays a crucial role in coronary endothelial damage, providing potential targets to treat KD.

Background: Manifesting as acute rash, fever and vasculitis, belonging to autoimmune syndrome, Kawasaki disease(KD) is prone to occur in infants and young children. Males and females is affected by KD at a ratio of 1.4 to 1.7: 1. KD is known to own many common clinical manifestations and complications, like coronary artery lesion(CAL) and coronary artery aneurysm(CAA). Polymorphisms of the rs6505162 locus in the miRNA-423 gene are associated with enhancive susceptibility to coronary artery disease and the alterations of the four cytokines IL-4., IL-10, IL-21, IL-22 in the early stages of diabetes. However, no researcher has reported whether rs6505162 is related to KD susceptibility or no. Therefore, we carried out the trial concentrating on the connection between miRNA-423 rs6505162 C>A polymorphism and KD susceptibility. Methods: To obtain the genotypes of rs6505162 in objects enrolled by 532 KD children and 623 control, we applied Taqman real-time PCR and all statistical analyses was carried out by SAS. Results: The comparison between all cases and all controls hinted that the rs6505162C>A polymorphism has no relationship with KD susceptibility. Nevertheless, a subgroup analysis revealed that the CA/AA genotypes of rs6505162 could reduce the occurrence of CAA (Adjusted age and gender odds ratio=1.30, 95%CI=1.02-1.67, P =0.037) and CAL (Adjusted OR=1.56, 95%CI=1.19-2.03, P =0.001)in KD patients. Conclusion: Our final results stated clearly that miRNA-423 rs6505162 polymorphism appears to be a protective element of CAL and CAA in southern Chinese suffers with KD.

The etiology and disease processes of viral myocarditis remain elusive. However, it is unknown whether early growth response-1 (Egr-1) and Target Egr-1 (TOE1) play a role in viral myocarditis. CVB3 infection was used to induce a mouse model of myocarditis, and cultured neonatal mouse cardiomyocytes were exposed to CVB3 to establish a cell model of VMC. RT-qPCR was used to determine mRNA expression levels of Egr-1, TOE1, P53, P21, and CVB3. Western blot analysis was employed to determine protein expression levels of Egr-1, TOE1, BAX, and BCL-2, and HE staining was utilized to observe pathological changes of myocardial inflammation. TUNEL staining was used to detect apoptosis levels in cardiomyocytes. In vivo results revealed that mRNA and protein expression levels of Egr-1 and TOE1 in myocardial tissues increased with prolonged CVB3 infection, BAX expression levels were upregulated, and BCL-2 expression levels were down-regulated. Moreover, in vitro findings demonstrated that 100nM Egr-1 siRNA and 100nM TOE1 siRNA could separately inhibit Egr-1 and TOE1 mRNA expression. The down-regulation of Egr-1 or TOE1 down-regulated P53, P21, and CVB3 mRNA expression in CVB3-infected myocardial cells decreased apoptotic protein BAX expression and increased anti-apoptotic protein BCL-2 expression. TUNEL assay revealed that Egr-1 or TOE1 gene down-regulation reduced CVB3 infection-induced apoptosis in cardiac myocytes. This study demonstrated that down-regulation of Egr-1 and TOE1 genes could inhibit cardiomyocyte apoptosis triggered by CVB3 virus infection and reduce CVB3 virus amplification, thus exerting a protective effect on myocardium.