Necrosis is a key factor in myocardial injury during cardiac pathological processes, such as myocardial infarction (MI), ischemia/reperfusion (I/R) injury and heart failure. Increasing evidence suggests that several aspects of necrosis are programmed and tightly regulated, so targeting the necrosis process has become a new trend for myocardial protection. Multiple cellular signaling pathways have been implicated in necrotic cell death, such as the death receptor-mediated extrinsic and mitochondrial intrinsic pathways. However, the precise mechanisms underlying myocardial necrosis remain unclear. In this study, we showed that apoptosis repressor with caspase recruitment domain (ARC) participated in the mitochondrial intrinsic pathway and inhibited myocardial necrosis by preventing the opening of the mitochondrial permeability transition pore (mPTP). ARC attenuated necrotic cell death triggered by exposure to 500 μM hydrogen peroxide (H2O2) in the cardiomyocyte cell line H9c2. In mice, ARC ameliorated myocardial necrosis, reduced the myocardial infarct size and improved long-term heart function during I/R injury. Mechanistically, it has been shown that the inhibition of necrosis by ARC was dependent on its mitochondrial localization and that ARC prevented the opening of mPTP by targeting CypD, the main regulator of mPTP. In addition, ARC expression was negatively regulated by the transcription factor p53 at the transcriptional level during the necrosis process. These findings identified the novel role of ARC in myocardial necrosis and delineated the p53-ARC-CypD/mPTP necrosis pathway during ischemia- and oxidative stress-induced myocardial damage, which can provide a new strategy for cardiac protection.
5 May 2022 in Journal of Materials Research and Technology
The dietary flavonoid quercetin is ubiquitously distributed in fruits, vegetables, and medicinal herbs. Quercetin has been a focal point in recent years due to its versatile health‐promoting benefits and high pharmacological values. It has well documented that quercetin exerts anticancer actions by inhibiting cell proliferation, inducing apoptosis, and retarding the invasion and metastasis of cancer cells. However, the exact mechanism of quercetin‐mediated cancer chemoprevention is still not fully understood. With the advances in high‐throughput sequencing technologies, the intricate oncogenic signaling networks have been gradually characterized. Increasing evidence on the close association between noncoding RNA (ncRNAs) and cancer etiopathogenesis emphasizes the potential of ncRNAs as promising molecular targets for cancer treatment. Available experimental studies indicate that quercetin can dominate multiple cancer‐associated ncRNAs, hence repressing carcinogenesis and cancer development. Thus, modulation of ncRNAs serves as a key mechanism responsible for the anticancer effects of quercetin. In this review, we focus on the chemopreventive effects of quercetin on cancer pathogenesis by targeting cancer‐relevant ncRNAs, supporting the viewpoint that quercetin holds promise as a drug candidate for cancer chemoprevention and chemotherapy. An in‐depth comprehension of the interplay between quercetin and ncRNAs in the inhibition of cancer development and progression will raise the possibility of developing this bioactive compound as an anticancer agent that could be highly efficacious and safe in clinical practice.
Ti alloys have been widely used in biomedical field due to good compatibility and corrosion resistance. However, corrosion-related failures of implanted Ti devices and prostheses have been regularly reported within the medical literature. The corrosion of Ti alloys has attracted much attention in vivo and in vitro. In the current study, the corrosion behavior of Ti6Al4V alloy was investigated using surface analysis and electrochemical tests. Corrosion of Ti6Al4V in 2 M hydrochloric acid is temperature dependent within the temperature range studied. It has found that the steady state current density at −510 mV vs. SCE (the primary passivation potential at the physiological temperature of 37°C) becomes higher with increasing temperature. The α phase of Ti6Al4V is preferentially dissolved relative to the β phase after potentiostatic measurement at primary passivation potential in 2 M HCl at 37°C. This investigation provides novel and useful information for Ti corrosion-related failures of biomedical implants and prostheses.
1 September 2018 in European Journal of Cell Biology