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Background: NLRP3 inflammasome activation and pyroptosis play a significant role in myocardial ischemia reperfusion injury (MI/RI). Geniposide was reported to show potential therapeutic use for MI/RI with its anti-inflammatory and anti-oxidative properties. However, research on the specific mechanism of geniposide has not been reported. Methods: The MIRI model of animal was created in male C57BL/6J mice and the hypoxia reoxygenation (H/R) model was established for the in vitro experiments. Neonatal rat ventricular myocytes (NRVMs) and H9c2 cells with knockdown of TXNIP or NLRP3 were used. Geniposide was administered to mice before vascular ligation. HE staining, 2,3,5-triphenyltetrazolium chloride (TTC) staining, echocardiography, oxidative stress and myocardial enzyme detection were used to evaluate the cardioprotective effect of geniposide. Meanwhile, pharmacological approaches of agonist and inhibitor were used to observe potential pathway for geniposide cardioprotective in vitro and in vivo. Moreover, ELISA kits were adopted to detect the levels of inflammatory factors, such as IL-1β and IL-18. The gene and protein expression of NLRP3 and pyroptosis-related factors in heart tissue were performed by RT-PCR, western blotting and immunofluorescence in vivo and in vitro, respectively. Results: Our results indicate that geniposide can reduce the area of myocardial infarction, improve heart function, and inhibit the inflammatory response in mice after MI/RI. In addition, RT-PCR and western blotting shown geniposide promoting AMPK phosphorylation to activate myocardium energy metabolism and reducing the levels of genes and proteins expression of NLRP3, ASC, N-GSDMD and cleaved caspase-1, IL-1β, IL-18. Meanwhile, geniposide improved NRVMs energy metabolism, which decreased ROS levels and the protein expression of TXNIP and thus suppressed the expression of NLRP3. AMPK antagonist or agonist and siRNA downregulation of TXNIP or NLRP3 were also verify the effect of geniposide against H/R injury. Further research found that geniposide promoted the translocation of TXNIP and reduce the binding of TXNIP and NLRP3. Conclusions: In our study, geniposide can significantly inhibit NLRP3 inflammasome activation via the AMPK signaling pathway and inhibit pyroptosis of cardiomyocytes in myocardial tissues. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effect of cardiac troponin I-interacting kinase (TNNI3K) on sepsis-induced myocardial dysfunction (SIMD) and further explore the underlying molecular mechanisms. In this study, a lipopolysaccharide- (LPS-) induced myocardial injury model was used. qRT-PCR was performed to detect the mRNA expression of TNNI3K. Western blot was conducted to quantitatively detect the expression of TNNI3K and apoptosis-related proteins (Bcl-2, Bax, and caspase-3). ELISA was performed to detect the content of lactate dehydrogenase (LDH) and creatine kinase (CK). TUNEL assay was used to detect the apoptosis of H9C2 cells. In LPS-induced H9C2 cells, TNNI3K was up regulated. Besides, the CK activity, the content of LDH, and the apoptosis of H9C2 cells were significantly increased after treatment with LPS. Silencing TNNI3K decreased the LDH release activity and CK activity and inhibited apoptosis of H9C2 cell. Further research illustrated that si-TNNI3K promoted the protein expression of Bcl-2 and decreased the protein expression of Bax and cleaved caspase-3. The study concluded that TNNI3K was upregulated in LPS-induced H9C2 cells. Importantly, functional research findings indicated that silencing TNNI3K alleviated LPS-induced H9C2 cell injury by regulating apoptosis-related proteins. [ABSTRACT FROM AUTHOR]

Hypoxia‐induced apoptosis is linked to the pathogenesis of myocardial infarction (MI) and heart failure. Ubiquitin‐specific peptidase 7 (USP7) is related to catabolic/pro‐apoptotic signaling. However, its role in cardiomyocyte injury is unclear. In this study, we aimed to investigate the role and the underlying regulatory mechanism of USP7 in MI. H9c2 cardiomyocytes were cultured in hypoxia to establish an in vitro model of myocardial hypoxic/ischemic injury. Sprague‐Dawley (SD) rats were used to establish animal models with MI. Quantitative real‐time polymerase chain reaction (qRT‐PCR) and Western blot assays were performed to evaluate the expression levels of miR‐409‐5p, USP7, and p53, respectively. After USP7 and miR‐409‐5p were selectively regulated in H9c2 cells, the inflammatory response, apoptosis, and cell viability were detected by ELISA, flow cytometry, and MTT assay, respectively. The interaction between USP7 and miR‐409‐5p was determined by bioinformatics analysis, qRT‐PCR, Western blot, and dual‐luciferase reporter assay. LVEF, LVIDd, and LVIDs of rats after MI were also measured. USP7 expression was markedly elevated while miR‐409‐5p expression was significantly down‐regulated in H9c2 cells under hypoxic culture. Augmentation of USP7 expression led to a dramatic promotion of hypoxia‐induced apoptosis of cardiomyocytes, accompanied by an increase in the secretion of the cytokines IL‐1β, TNF‐α, and IL‐6. Myocardial injury markers LDH, cTnI, and CK‐MB expressions were also increased. Besides, overexpression of USP7 aggravated left ventricular remodeling and decreased left ventricular function of the rats. Conversely, the up‐regulation of miR‐409‐5p expression protected H9c2 cells from apoptosis and inhibited the release of cytokines and myocardial injury. Left ventricular remodeling and left ventricular function were also improved by miR‐409‐5p overexpression. Furthermore, USP7 was identified as a target of miR‐409‐5p and the overexpression of miR‐409‐5p reversed the effects of USP7 on H9c2 cells. USP7 exacerbates myocardial ischemic injury by promoting inflammation and apoptosis of cardiomyocytes, and the up‐regulation of its expression is partly caused by the down‐regulation of miR‐409‐5p expression. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) play critical roles in the progression of laryngeal cancer (LC). In this study, we aimed to investigate whether miR-149 is associated with the prognosis of patients with LC. A total of 97 laryngeal squamous cell carcinoma patients who underwent tumor resection were included in our follow-up study. In vitro studies was performed in cancer cell line Hep-2 to explore the antitumor role of miR-149 in LC. We found that the expression of miR-149 was significantly lower in tumor tissues, compared with vocal cord polyp tissues (P<0.05). Kaplan-Meier analysis revealed that miR-149 expression status is significantly associated with survival duration (log rank test, P<0.05), and multivariate Cox regression analysis revealed that patients with low miR-149 expression had shorter survival times compared with patients with high miR-149 expression. In vitro studies revealed that the exogenous expression of miRNA-149 inhibits the proliferation of human Hep-2 cells and induces cell apoptosis. Our study suggests that miR-149 expression in laryngeal squamous cell carcinoma tissues is critically associated with the prognosis of patients, and the ectopic expression of miR-149 in Hep-2 cells inhibits proliferation and cell cycle progression. [ABSTRACT FROM AUTHOR]