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Key message: Oxidative stress and apoptosis-like programmed cell death, induced in part by H O , are two key factors that damage cells during plant cryopreservation. Their inhibition can improve cell viability. Abstract: We hypothesized that oxidative stress and apoptosis-like event induced by ROS seriously impact plant cell viability during cryopreservation. This study documented changes in cell morphology and ultrastructure, and detected dynamic changes in ROS components (O, HO and OH·), antioxidant systems, and programmed cell death (PCD) events during embryonic callus cryopreservation of Agapanthus praecox. Plasmolysis, organelle ultrastructure changes, and increases in malondialdehyde (a membrane lipid peroxidation product) suggested that oxidative damage and PCD events occurred at several early cryopreservation steps. PCD events including autophagy, apoptosis-like, and necrosis also occurred at later stages of cryopreservation, and most were apoptosis. HO is the most important ROS molecule mediating oxidative damage and affecting cell viability, and catalase and AsA-GSH cycle are involved in scavenging the intracellular HO and protecting the cells against stress damage in the whole process. Gene expression studies verified changes of antioxidant system and PCD-related genes at the main steps of the cryopreservation process that correlated with improved cell viability. Reducing oxidative stress or inhibition of apoptosis-like event by deactivating proteases improved cryopreserved cell viability from 49.14 to 86.85 % and 89.91 %, respectively. These results verify our model of ROS-induced oxidative stress and apoptosis-like event in plant cryopreservation. This study provided a novel insight into cell stress response mechanisms in cryopreservation. [ABSTRACT FROM AUTHOR]

Atherosclerosis (AS) is mainly characterized by the activation of inflammatory cells and chronic inflammatory responses after cell injury. Pyroptosis is a form of programmed cell death (PCD) accompanied by the release of inflammatory factors. Many studies have shown that pyroptosis plays an important role in AS. Increasing evidence also indicates that long non-coding RNA H19 (lncRNA H19) involved in AS. However, whether the role of lncRNA H19 in AS is related to pyroptosis and the underlying mechanisms are largely unknown. In this study, we found that oxidized low-density lipoprotein (ox-LDL) induced pyroptosis and decreased the expression of lncRNA H19 in Raw 264.7 cells. Besides, silencing endogenous lncRNA H19 increased inflammatory responses and pyroptosis while exogenous overexpression of lncRNA H19 reversed this effect. Notably, we identified that the inhibitor of caspase-1 (XV-765) completely abrogated the silencing endogenous lncRNA H19 mediated pyroptosis. In addition, we found that lncRNA H19 inhibited ox-LDL-induced activation of nuclear factor-kappa B (NF-κB), mitochondrial dysfunction, and reduced the production of reactive oxygen species (ROS). Moreover, VX-765 impaired the silencing endogenous lncRNA H19 mediated pyroptosis. Overall, these findings indicated that lncRNA H19 may play an important role in pyroptosis and may serve as a potential therapeutic target for AS. [ABSTRACT FROM AUTHOR]

As a polyphenolic compound, resveratrol (Res) is widely present in a variety of plants. Previous studies have shown that Res can inhibit various tumors. However, its role in c remains largely unexplored. In the present study, we first demonstrated that Res inhibited cell viability and induced apoptosis of glioblastoma A172 cell. Further experiments showed that Res induced mitochondrial dysfunction and activated the activity of caspase‐9. Functional studies have found that Res treatment is associated with an increase in the expression of Pak2. Interestingly, inhibition of Pak2 could further augment the proapoptotic effect of Res. Mechanistically, Pak2 inhibition induced reactive oxygen species overproduction, mitochondria‐JNK pathway activation, and AMPK‐YAP axis suppression. However, overexpression of YAP could abolish the anticancer effects of Res and Pak2 inhibition, suggesting a necessary role played by the AMPK‐YAP pathway in regulating cancer‐suppressive actions of Res and Pak2 inhibition. Altogether, our results indicated that Res in combination with Pak2 inhibition could further enhance the anticancer property of Res and this effect is mediated via the AMPK‐YAP pathway. [ABSTRACT FROM AUTHOR]

Background: Chronic alcohol intake increases circulating endotoxin levels causing excessive inflammation that aggravates the liver injury. (E)‐2,3‐dimethoxy‐4′‐methoxychalcone (L6H21), a derivative of chalcone, has been found to inhibit inflammation in cardiac diseases and nonalcoholic fatty liver disease. However, the use of L6H21 in alcoholic liver disease to inhibit exotoxin‐associated inflammation has not been explored. In this study, we examined the effects of L6H21 on EtOH + LPS‐induced hepatic inflammation, steatosis, and liver injury and investigated the underlying mechanisms. Methods: C57BL6 mice were treated with 5% EtOH for 10 days, and LPS was given to the mice 6 hours before sacrificing. One group of mice was supplemented with L6H21 with EtOH and LPS. RAW264.7 cells were used to analyze the effects of L6H21 on macrophage activation. Results: EtOH + LPS treatment significantly increased hepatic steatosis and serum levels of alanine transaminase (ALT) and aspartate transaminase (AST), which were reduced by L6H21 treatment. EtOH + LPS treatment increased hepatic inflammation, as shown by the increased hepatic protein levels of Toll‐like receptor‐4, p65, and p‐IκB, and increased oxidative stress, as shown by protein carbonyl levels and reactive oxygen species formation, which were reduced by L6H21 treatment. In addition, L6H21 treatment markedly inhibited EtOH + LPS‐elevated hepatic protein levels of NLRP3, cleaved caspase‐1, cleaved IL‐1β, and caspase‐1‐associated apoptosis. Conclusions: Our results demonstrate that L6H21 treatment inhibits EtOH + LPS‐induced liver steatosis and injury through suppression of NLRP3 inflammasome activation. L6H21 may be used as an alternative strategy for ALD prevention/treatment. [ABSTRACT FROM AUTHOR]