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Methionine adenosyltransferase 2 A (MAT2A) mediates the synthesis of methyl donor S-Adenosylmethionine (SAM), providing raw materials for methylation reactions in cells. MAT2A inhibitors are currently used for the treatment of tumors with methylthioadenosine phosphorylase (MTAP) deficiency in clinical research. Methyltransferase like 3 (METTL3) catalyzes N6-methyladenosine (m 6 A) modification of mRNA in mammalian cells using SAM as the substrate which has been shown to affect the tumorigenesis of non-small cell lung cancer (NSCLC) from multiple perspectives. MAT2A-induced SAM depletion may have the potential to inhibit the methyl transfer function of METTL3. Therefore, in order to expand the applicability of inhibitors, improve anti-tumor effects and reduce toxicity, the combinational effect of MAT2A inhibitor AG-270 and METTL3 inhibitor STM2457 was evaluated in NSCLC. The results showed that this combination induced cell apoptosis rather than cell cycle arrest, which was non-tissue-specific and was independent of MTAP expression status, resulting in a significant synergistic anti-tumor effect. We further elucidated that the combination-induced enhanced apoptosis was associated with the decreased m 6 A level, leading to downregulation of PI3K/AKT protein, ultimately activating the apoptosis-related proteins. Unexpectedly, although combination therapy resulted in metabolic recombination, no significant change in methionine metabolic metabolites was found. More importantly, the combination also exerted synergistic effects in vivo. In summary, the combination of MAT2A inhibitor and METTL3 inhibitor showed synergistic effects both in vivo and in vitro, which laid a theoretical foundation for expanding the clinical application research of the two types of drugs., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Methylmercury (MeHg) is a bio-accumulative global environmental contaminant present in fish and seafood. MeHg accumulates in the aquatic environment and eventually reaches the human system via the food chain by bio-magnification. The central nervous system is the primary target of toxicity and is particularly vulnerable during development. It is well documented that developmental MeHg exposure can lead to neurological alterations, including cognitive and motor dysfunction. Apoptosis is a primary characteristic of MeHg-induced neurotoxicity, and may be regulated by autophagic activity. However, mechanisms mediating the interaction between apoptosis and autophagy remains to be explored. Autophagy is an adaptive response under stressful conditions, and the basal level of autophagy ensures the physiological turnover of old and damaged organelles. Autophagy can regulate cell fate through different crosstalk signaling pathways. A complex interplay between autophagy and apoptosis determines the degree of apoptosis and the progression of MeHg-induced neurotoxicity as demonstrated by pre-clinical models and clinical trials. This review summarizes recent advances in the roles of autophagy and apoptosis in MeHg neurotoxicity and thoroughly explores the relationship between them. The autophagic pathway may be a potential therapeutic target in MeHg neurotoxicity through modulation of apoptosis., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Methylmercury (MeHg) is a environmental contaminant, which can induce neurotoxic effects. So far, the exact molecular mechanisms of autophagy and its effect on apoptosis in MeHg-induced neurotoxicity have not been elucidated. Here, rats were exposed to MeHg (4, 8, or 12 μmol/kg) for 4 weeks to evaluate the dose-effect relationship between MeHg and apoptosis, or autophagy in cerebral cortex. On this basis, rapamycin (Rapa) or 3-methyladenine (3-MA) was administrated to further explore the regulatory mechanisms of autophagy on MeHg-induced neuronal apoptosis. The pathological changes, autophagy or apoptosis levels, expression of autophagic or apoptotic-associated factors such as mTOR, S6K1, 4EBP1, Vps34, Beclin1, p62, LC3, Bcl-2/Bax, caspase, or MAPKs were investigated. Results showed that MeHg dose-dependently induced pathological changes in cerebral cortex, and the levels of autophagy and apoptosis were increased. Furthermore, Rapa pretreatment antagonized MeHg-induced apoptosis, whereas 3-MA further aggravated apoptosis, which were supported by findings that Rapa activated mTOR-mediated autophagy while 3-MA inhibited Vps34-related autophagy, further affect neuronal apoptosis through regulation of apoptotic factors mentioned above. In conclusion, the findings indicated that MeHg dose-dependently induced autophagy or apoptosis, and mTOR or Vps34 may play important roles in mediating autophagy, which further regulated apoptosis through MAPKs or mitochondrial apoptosis pathways., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Diclofenac sodium (DFS), a nonsteroidal anti-inflammatory drug, is frequently used in ophthalmology, but it causes negative effects on corneas. The mechanisms underlying the toxicities to corneas remains unclear. The present study was designed to assess the cytotoxicity of DFS to human corneal epithelial (HCEP) cells in vitro and further investigate its related mechanisms. The HCEP cells were treated with DFS at different concentrations ranging from 0.003 125% to 0.1%. DFS showed a dose- and time-dependent cytotoxicity to HCEP cells including abnormal morphology and declined viability. The 0.05% DFS-treated HCEP cells presented cell cycle arrest at S phase, reactive oxygen species (ROS) overproduction, and positive staining of phosphorylated H2AX, suggesting that DFS caused ROS-mediated DNA damage. The upregulation of p53 expression, formation of apoptotic body, phosphatidylserine externalization, and DNA ladder demonstrated that the p53-dependent apoptosis pathway was involved in the cytotoxicity of DFS. Furthermore, DFS activated caspase-8, caspase-9, and caspase-3 altered the expression levels of Bcl-2 family proteins including tBid, Bax, and Bcl-2, as well as increased poly(ADP-ribose) polymerase (PARP) cleavage. DFS also induced ΔΨm disruption, resulting in the release of cytochrome c and apoptosis-inducing factor into the cytoplasm. Additionally, the DFS-induced apoptosis was alleviated by p53 inhibitor. Taken together, DFS triggered p53-dependent apoptosis in HCEP cells via ROS-mediated crosstalk between the extrinsic and intrinsic pathways.

miRNAs are a class of small non-coding RNAs that are involved in various biological processes. In the preliminary work of the laboratory, found that miR-383-5p was down-regulated in the liver tissue of acute cold stress rats and has been shown to be an important regulatory factor in tumour proliferation, but there are very few studies involving the mediation of cold stress in rat liver tissues. Therefore, the purpose of this study was to determine the effect of miR-383-5p on the livers of cold stress rats by simulating the cold stress state of rat liver tissues in vitro using H 2 O 2 to induce rat hepatocyte oxidative stress. The results showed that MDA content, Caspase 3 and Cyto C protein levels increased significantly; GPx activity and SOD1 protein levels decreased significantly and miR-383-5p expression was significantly down-regulated in rat liver tissues after cold stress. Different concentrations of H 2 O 2 was added to rat hepatocytes, and the results showed that the expression of miR-383-5p, the ROS level, and the apoptosis rate in rat hepatocytes was increased significantly in a concentration-dependent fashion. Transfection of miR-383-5p inhibitor revealed that the apoptosis rate of rat hepatocytes, and the protein level of apoptosis-related protein Caspase 3 were reduced; the results of the dual-luciferase reporter gene assay showed that miR-383-5p targeted regulation of Bcl2. The results suggested that the expression of miR-383-5p was up-regulated in oxidative stress rat hepatocytes and may aggravate the apoptosis of rat hepatocytes induced by targeting inhibition of Bcl2 translation., (© 2020 Blackwell Verlag GmbH.)

Norfloxacin (NOR) is applied clinically to treat keratitis. However, NOR has brought severe side-effects for human corneal epithelium (HCEP) due to overdose and potential toxicity. In this study, two in vitro experimental models including monolayer HCEP cells and tissue-engineered human corneal epithelium (TE-HCEP) were used to explore the cytotoxicity and its related mechanisms. The HCEP cells treated with NOR at concentrations from 0.1875 to 3.0 mg/mL displayed abnormal morphology, declined viability, and increased plasma membrane permeability. Moreover, 0.75 mg/mL NOR induced chromatin condensation, S phase arrest, phosphatidylserine externalization, and formation of apoptotic body through activation of caspase-2/-8/-9/-3, downregulation of Bcl-2 and Bcl-xL, upregulation of Bad and Bax, mitochondrial transmembrane potential disruption and release of cytochrome c and apoptosis inducing factor into cytosol, whereas 1.5 mg/mL and 3.0 mg/mL NOR upregulated the expressions of receptor-interacting protein kinase 1 (RIPK1), RIPK3 and mixed lineage kinase domain-like (MLKL) together with inactivation of caspase-2/-8. Furthermore, 0.1875-3.0 mg/mL NOR destroyed the multilayer structure of TE-HCEP model due to a dose-dependent cytotoxicity, which validated the above results. Overall, low-dose (0.1875-0.75 mg/mL) NOR induced apoptosis through mitochondrion-dependent and death receptor-mediated pathways, and high-dose (1.5-3.0 mg/mL) NOR triggered necroptosis via RIPK1-RIPK3-MLKL cascade in HCEP cells., Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest regarding the publication of this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Methylmercury (MeHg) is a potent neurotoxin,which leads to a wide range of intracellular effects. The molecular mechanismsassociated to MeHg-induced neurotoxicity have not been fully understood.Oxidative stress, as well as synaptic glutamate (Glu) dyshomeostasis have beenidentified as two critical mechanisms during MeHg-mediated cytotoxicity. Here,we developed a rat model of MeHg poisoning to evaluate its neurotoxic effectsby focusing on cellular oxidative stress and synaptic Glu disruption. Inaddition, we investigated the neuroprotective role of alpha-lipoic acid (α-LA), a natural antioxidant, todeeply explore the underlying interaction between them. Fifty-six rats wererandomly divided into four groups: saline control, MeHg treatment (4 or 12μmol/kg MeHg), and α-LApre-treatment (35 μmol/kg α-LA+12μmol/kg MeHg). Rats exposed to 12 μmol/kg MeHg induced neuronal oxidativestress, with ROS accumulation and cellular antioxidant system impairment. Nrf2 andxCT pathways were activated with MeHg treatment. The enzymatic or non-enzymaticof cellular GSH synthesis were also disrupted by MeHg. On the other hand, the abnormalactivities of GS and PAG disturbed the "Glu-Gln cycle", leading to NMDARsover-activation, Ca2+ overload, and the calpain activation, which acceleratedNMDARs degradation. Meanwhile, the high expressions of phospho-p44/42 MAPK,phospho-p38 MAPK, phospho-CREB, and the high levels of caspase 3 and Bax/Bcl-2 finallyindicated the neuronal apoptosis after MeHg exposure. Pre-treatment with α-LA significantly preventedMeHg-induced neurotoxicity. In conclusion, the oxidative stress and synapticGlu dyshomeostasis contributed to MeHg-induced neuronal apoptosis. Alpha-LAattenuated these toxic effects through mechanisms of anti-oxidation andindirect Glu dyshomeostasis prevention., (© 2020 Wiley Periodicals, Inc.)

Background: Epulis has a tumor-like appearance but is considered to be a massive reactive lesion rather than a true neoplasia. Limited information about the pathogenesis of epulis is available. The purpose of our study was to identify potential signaling pathways in fibrous epulis through transcriptome profiling., Methods: Differentially expressed genes (DEGs) between fibrous epulis lesions and normal gingival tissues were detected using RNA sequencing (RNAseq). The expression levels of eighteen genes were validated using quantitative real-time PCR (qRT-PCR)., Results: RNAseq identified 533 upregulated genes and 732 downregulated genes. The top 10 upregulated genes were IL11, OSM, MMP3, KRT75, MMP1, IL6, IL1B, IL24, SP7, and ADGRG3. The top 10 downregulated genes were BCHE, TYR, DCT, KRT222, RP11-507K12.1, COL6A5, PMP2, GFRA1, SCN7A, and CDH19. KEGG pathway analysis further indicated that the DEGs were enriched in "Pathways in cancer" and the "Ras signaling pathway". quantitative real-time PCR verified that the expression levels of SOS1, HRAS, PIK3CA, AKT3, IKBKA, IKBKB, NFKB1, BCL2, BCL2L1, XIAP, BIRC2, and BIRC3 were increased significantly., Conclusions: The current transcriptomic profiling study reveals that in fibrous epulis, RAS-PI3K-AKT-NF-κB pathway transcriptionally regulates the expression of BCL2 family and IAP family genes, leading to increased proliferation and apoptosis inhibition., (© 2019 The Authors. Journal of Clinical Laboratory Analysis published by Wiley Periodicals, Inc.)

Overexposure to manganese (Mn) is neurotoxic. Our previous research has demonstrated that the interaction of endoplasmic reticulum (ER) stress and autophagy participates in the early stage of Mn-mediated neurotoxicity in mouse. However, the mechanisms of ER stress signalling pathways in the initiation of autophagy remain confused. In the current study, we first validated that ER stress-mediated cell apoptosis is accompanied by autophagy in SH-SY5Y cells. Then, we found that inhibiting ER stress with 4-phenylbutyrate (4-PBA) decreased ER stress-related protein expression and reduced cell apoptosis, whereas blocking autophagy with 3-methyladenine (3-MA) increased cell apoptosis. These data indicate that protective autophagy was activated to alleviate ER stress-mediated apoptosis. Knockdown of the protein kinase RNA-like ER kinase (PERK) gene inhibited Mn-induced autophagy and weakened the interaction between ATF4 and the LC3 promoter. Our results reveal a novel molecular mechanism in which ER stress may regulate autophagy via the PERK/eIF2α/ATF4 signalling pathway. Additionally, Mn may activate protective autophagy to alleviate ER stress-mediated apoptosis via the PERK/eIF2α/ATF4 signalling pathway in SH-SY5Y cells., (© 2019 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Background: Acute respiratory distress syndrome (ARDS) is a severe form of acute lung injury during which severe inflammatory responses induce cell apoptosis, necrosis, and fibrosis. Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a multiple function long noncoding RNA that was found overexpressed during acute lung injury. However, the roles of MALAT1 in ARDS patients are still unknown., Methods: Total RNA was extracted from the plasma, plasma exosome, and peripheral blood mononuclear cells (PBMCs) from 65 ARDS patients and 36 healthy controls. The MALAT1 and six candidate miRNAs levels were detected by qRT-PCR. The interaction between MALAT1 and miR-425 was predicted using a bioinformatics tool and verified by dual luciferase assay. Exosomes from ARDS patients were cultured with A549 and HFL-1 cells to confirm the delivery of miR-425 by exosomes. Cell apoptosis and viability were determined by flow cytometry and MTT assay., Results: We found MALAT1 was significantly increased in the ARDS patients' plasma and PBMCs. The MALAT1 level in PBMCs was negatively correlated with exosomal miR-425 level. MALAT1 interacted with miR-425 and protected phosphatase and tensin homolog (PTEN) expression in A549 and HFL-1 cells. Exosomes from ARDS patients delivered less miR-425 into A549 and HFL-1 cells and induced cell apoptosis via upregulating PTEN., Conclusion: This study identified increased MALAT1 and decreased miR-425 in ARDS patients and unveiled their roles during the pathogenesis of ARDS., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2019 Lu Wang et al.)

Lung cancer (especially, non-small cell lung cancer [NSCLC]) is one of the most malignant cancers in the world. Hinesol is the major component of the essential oil of Atractylodes lancea (Thunb.) DC and possesses the most promising anticancer function. However, the effects and molecular mechanism of hinesol on antiproliferation in NSCLC cells has not been well understood. In this study, we found that hinesol effectively inhibited the A549 and NCI-H1299 cells in a dose- and time-dependent manner by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay. In addition, hinesol induced cell cycle arrest at G0/G1 phase and apoptosis assessed by flow cytometry in A549 cells. Furthermore, Western blot analysis showed that hinesol decreased phosphorylation of mitogen-activated protein kinase, extracellular signal-regulated kinase, IκBα, and p65 inhibited the expressions of Bcl-2, cyclin D1 and upregulated the expression of Bax. Based on these results, hinesol might be a potential drug candidate of anti-NSCLC for therapy., (© 2019 Wiley Periodicals, Inc.)

Methyl-mercury (MeHg) is a dangerous environmental contamination biotransformed from mercury or inorganic mercury compounds in waterways, which induces severe toxic effects in central nervous system. Oxidative stress is involved in various ways of intracellular physiological or pathological processes including neuronal apoptosis. For understanding the ways that oxidative stress participating in MeHg-induced apoptosis, the current study attempted to explore the effects of oxidative stress on endoplasmic reticulum (ER) and mitochondria function, especially focussing on ER stress followed by unfold protein response (UPR), as well as mitochondrial apoptosis pathways activation in primary cultured cortical neurons. Cells were exposed to 0, 0.25, 0.5, or 1 µM MeHg for 1-6 h, respectively, followed by cell viability quantification. For further experiments, 100 µM of 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (trolox) pre-treatment for 3 h followed by 1 µM MeHg for 6 h were performed for evaluation of oxidative stress, neuronal apoptosis, ER stress, UPR activation, and mitochondrial dysfunction. Results showed that MeHg induced neuronal oxidative stress, apoptosis, up-regulating glucose-regulated protein (GRP78, GRP94), spliced Xbp1, activating transcription factor 4 (ATF4) mRNA, with activation of UPR including PKR-like ER kinase-eIF2α, inositol-requiring enzyme 1, and ATF6 pathways, as well as C/EBP homologous transcription factor protein and cleaved caspase-12 up-regulation. In addition, mitochondrial function was disrupted by MeHg, which was supported by caspase-3 and caspase-9 activation, and high levels of cytoplasm cytochrome C and apoptosis induce factor. Trolox pre-treatment significantly blocked neuronal apoptosis, ER stress, UPR activation, as well as mitochondrial dysfunction, in addition to the direct anti-oxidation. In conclusion, MeHg induces neuronal apoptosis through ER and mitochondria pathway, oxidative stress plays important roles in mediating apoptosis pathways activation.

Background/aims: Several long non-coding RNAs (lncRNAs) play vital roles in osteoarthritis (OA), whereas the role of lncRNA RP11-445H22.4 in OA remains unclear. The study aimed to investigate the effect of lncRNA RP11-445H22.4 on lipopolysaccharide (LPS)-induced cell viability, apoptosis and inflammatory injury of OA., Methods: The expression of RP11-445H22.4, miR-301a and CXCR4 in human cartilage ATDC5 cells were altered by transfection, and then cells were exposed to 5 µg/ml LPS for 12 h. Then cell viability, apoptosis, apoptosis-related factors and inflammatory cytokines were analyzed by CCK-8, flow cytometry, western blot, RT-qPCR and ELISA, respectively. Dual-luciferase reporter assay was performed to assess the binging sites of RP11-445H22.4 and miR-301a. The signal pathways of NF-κB and MAPK/ ERK were determined by western blot., Results: LPS reduced cell viability, increased apoptosis and stimulated release of IL-1β, IL-6, IL-8 and TNF-α. However, RP11-445H22.4 inhibition significantly rescued LPS-induced injuries by promoting cell viability, suppressing apoptosis and inflammatory cytokines secretions in ATDC5 cells. In addition, miR-301a directly bound to RP11-445H22.4, and suppression of miR-301a inversed the effects of RP11-445H22.4 inhibition. Furthermore, CXCR4 was a direct target of miR-301a, and CXCR4 silencing increased cell viability, decreased apoptosis and inflammatory cytokines secretions in LPS-treated ATDC5 cells. Besides, we found that CXCR4 silencing blocked LPS-activated NF-κB and MAPK/ERK pathways., Conclusions: The study indicated that lncRNA RP11-445H22.4-miR-301a-CXCR4 axis played an important role in cartilage ATDC5 cells and provided a theoretical basis of lncRNA RP11-445H22.4 in OA., (© 2018 The Author(s). Published by S. Karger AG, Basel.)

MUC1, a membrane tethered mucin glycoprotein, is overexpressed in > 60% of human pancreatic cancers (PCs), and is associated with poor prognosis and enhanced metastasis. Here, we report the effect of silencing MUC1 expression on the growth, migration and invasive ability of pancreatic cancer cells, and explored its mechanisms. We observed that siRNA mediated suppression of the MUC1 expression significantly reduced invasive and migrative capability and induced apoptosis of the pancreatic cancer PANC-1 cells. We found that Slug was inhibited in the MUC1 siRNA transfected PANC-1 cells (MUC1 siRNA/PANC-1 cells). Expression of PUMA and E-cadherin was increased in the MUC1 siRNA/PANC-1 cells. PANC-1 cells overexpressing full long Slug gene (when transfected with Slug cDNA plasmid) significantly inhibited PUMA and E-cadherin expression in the MUC1 siRNA/PANC-1 cells. Silencing PUMA expression inhibited apoptosis in the MUC1 siRNA transfected PANC-1 cells (MUC1 siRNA/PANC-1 cells). Silencing E-cadherin expression restored the invasion and migration ability in the MUC1 siRNA/PANC-1 cells. We therefore concluded that silencing MUC1 expression inhibited migration and invasion, and induced apoptosis of PANC-1 cells via downregulation of Slug and upregulation of Slug dependent PUMA and E-cadherin expression. MUC1 could serve as a potential therapeutic target in pancreatic cancer.

Synaptotagmin‑7 (SYT7) is a member of the synaptotagmin gene family, and encodes a protein that mediates the calcium‑dependent regulation of membrane trafficking during synaptic transmission. A previous study demonstrated that the expression of SYT7 is associated with prostate cancer and serves an important role in development of prostate cancer. However, the roles of SYT7 in the progression of glioma remain unknown. In the present study, reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) analysis demonstrated that SYT7 was expressed in three human glioma cell lines. Western blotting and RT‑qPCR analysis demonstrated the knockdown efficiency of SYT7 shRNA in 293T cells and U87MG cells. Celigo Image Cytometer Analysis, a caspase‑3/7 assay, flow cytometry and an MTT assay demonstrated that the proliferation of U87MG cells was inhibited as SYT7 was downregulated by a lentiviral vector expressing SYT7 shRNA, via the promotion of cellular apoptosis. The results of the present study demonstrated that the downregulation of SYT7 inhibited glioblastoma growth by promoting cellular apoptosis, and that SYT7 may therefore be a potential target for glioma intervention.

Currently, multiple microRNAs (miRNAs) have been found to play vital roles in the pathogenesis of osteosarcoma. This study aimed to investigate the role of miR-21 in osteosarcoma. The level of miR-21 in 20 pairs of osteosarcoma and corresponding adjacent tissues was monitored by qPCR. Human osteosarcoma cell line SAOS-2 was transfected with either miR-21 mimic or miR-21 inhibitor, and then cell viability, survival, and apoptosis were measured by MTT, colony formation assay, and flow cytometry. A target of miR-21 was predicted by the microRNA.org database and verified in vitro by using luciferase reporter, qPCR, and Western blot analyses. Finally, cells were cotransfected with siRNA against caspase 8 and miR-21 inhibitor, and the apoptotic cell rate was determined again. Results showed that the mRNA level of miR-21 was highly expressed in osteosarcoma tissues compared with adjacent tissues. Overexpression of miR-21 improved cell viability and survival but suppressed apoptosis. Caspase 8 was a direct target of miR-21, and it was negatively regulated by miR-21. Moreover, miR-21 suppression attenuated caspase 8 silencing and induced the decrease in apoptosis. In conclusion, overexpression of miR-21 suppressed SAOS-2 cell apoptosis via directly targeting caspase 8.

Methylmercury (MeHg), an extremely dangerous environmental pollutant, accumulating preferentially in central nervous system, causes a series of cytotoxic effects. The present study explored the mechanisms which contribute to MeHg-induced neurotoxicity focusing on the oxidative stress in rat cerebral cortex. In addition, the protective effects of alpha-lipoic acid (LA), a potent antioxidant on MeHg-mediated neuronal injury, was also investigated in current study. A MeHg poisoning model was established as 64 rats randomly divided into 4 groups of which saline control group, MeHg-treated groups (4 and 12 μmol kg -1 ), and LA pretreatment (35 μmol kg -1 ) group, respectively. After administration of 12 μmol kg -1 MeHg for 4 weeks, it was found that obvious pathological changes and apoptosis in neuronal cells. Meanwhile, total Hg levels elevated significantly, superoxide dismutase (SOD) and gluthathione peroxidase (GSH-Px) activities were inhibited, and ROS formation elevated, which might be critical to aggravate oxidative stress in cerebral cortex. In addition, NF-E2-related factor 2 (Nrf2) pathways were activated, as heme oxygenase-1 (HO-1) and γ-glutamylcysteine synthetase heavy subunit (γ-GCSh) expressions were up-regulated obviously by MeHg exposure. Moreover, activities of Na + -K + -ATPase and Ca 2+ -ATPase were inhibited, leading to intracellular calcium (Ca 2+ ) overload. LA pre-treatment partially reduced MeHg neurotoxic effects via anti-oxidation pathways. In conclusion, these findings clearly indicated that MeHg aggravated oxidative stress and Ca 2+ overload in cerebral cortex. LA possesses the ability to prevent MeHg neurotoxicity through its anti-oxidative properties. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 931-943, 2017., (© 2016 Wiley Periodicals, Inc.)

Background: Chronic myelogenous leukemia (CML) is a hematological stem cell disorder. Tyrosine kinase inhibitors (TKIs) are the standard treatments for CML, but a number of patients fail to respond effectively due to gene mutations. Celecoxib, a cyclooxygenase-2 (COX-2) inhibitor, has been shown to have anti-tumor effect on solid tumor whereas the anti-CML effect and its underlying mechanism have not been completely elucidated., Methods: The cytotoxic effects of celecoxib and/or imatinib were evaluated by MTT assay. Cell cycle distribution was examined by propidium iodide (PI) assay. Apoptosis or necrosis was analyzed by Annexin-V/PI, Hoechst 33342 staining and Western blot assays. Autophagy suppression effect of celecoxib was examined by Western blot and LysoTracker probe labelling. Lysosensor probe labelling was used to detect the effect of celecoxib on the lysosomal function., Results: In this study, we found that celecoxib had therapy efficacy in KBM5 and imatinib-resistant KBM5-T315I CML cell lines. Celecoxib caused significant cytotoxic effect in both cell lines, especially in KBM5-T315I cells exposed to celecoxib for 72 h. Moreover, celecoxib induced necrosis and apoptosis while inhibited autophagy in CML cell lines and patient samples. Furthermore, this study demonstrated that celecoxib prevented the autophagic flux by inhibiting lysosome function. Celecoxib was tested in combination with imatinib, demonstrating that celecoxib could strengthen the cytotoxicity of imatinib in imatinib-resistant CML cells., Conclusions: These findings showed that celecoxib had therapy efficacy on CML cells. And it is first time to demonstrate that celecoxib is an autophagy suppresser and a combination of celecoxib and imatinib might be a promising new therapeutic strategy for imatinib-resistant CML cells.

Background: Imbalance in bone remodeling causes osteoporosis., Purpose: In the present study, we identified that protocatechuic acid inhibits osteoclast differentiation and induces apoptosis in RAW264.7 murine macrophage cells., Methods: Tartrate-resistance acid phosphatase (TRAP) activity was used to determine osteoclast formation. Oxidative stress was analyzed through ROS, lipid peroxide and antioxidant enzyme activities. Osteoclast and inflammatory marker expressions were determined through western blot. Apoptosis induction was determined through membrane potential analysis, Cyt c release and caspase activation., Results: Protocatechuic acid dose dependently reduced RANKL-induced tartrate-resistance acid phosphatase (TRAP) activity and multinucleated osteoclasts formation. Protocatechuic acid inhibited oxidative stress by reducing ROS and lipid peroxide levels with concomitant increase in antioxidant status. Osteoclast specific marker expression (MMP, c-Src, TRAP, TRAF-6, Cathepsin) and transcription factor AP-1 and NFATc1 expression were significantly down regulated by protocatechuic acid. Further, MAPK activation and inflammatory proteins such as NF-kB and COX-2 expressions were significantly down regulated by protocatechuic acid treatment. Further, protocatechuic acid enhanced Nrf-2 translocation into the nucleus. In mature osteoclasts, protocatechuic acid induced apoptosis by inducing mitochondrial membrane potential, cytochrome c release and caspase activation., Interpretation: The present findings shows evidence that, protocatechuic acid prevents osteoclast differentiation through regulating oxidative stress, inflammation and inducing apoptosis in RAW264.7 murine macrophage cells., (Copyright © 2016. Published by Elsevier Masson SAS.)

Background: MicroRNAs (miRNAs) have been demonstrated playing important roles in the procession of prostate cancer cells transformation from androgen-dependence to androgen-independence., Methods: We conducted the miRNA microarray and realtime PCR analyses in both androgen-dependent (ADPC) and androgen-independent prostate cancer (AIPC) tissues. We also explored the role of hsa-miR-146a-5p (miR-146a) in MSKCC prostate cancer clinical database. Moreover, the impact of miR-146a on prostate cancer cells apoptosis were detected by Hoechst staining and fluorescence-activated cell sorter (FACS). Its target is predicted by DIANA LAB online database and the result was assumed by western blotting and luciferase assay., Results: We demonstrated that miR-146a was down-regulated in AIPC tissues and cell lines compared to that in the ADPC tissues. In MSKCC data re-analyses, we found that miR-146a was underexpressed in metastatic prostate cancer tissues and those with Gleason score >8, moreover, low level of miR-146a represented a high biochemical relapse rate after radical prostatectomy. In the functional analyses, we transfected miR-146a mimics into CPRC cell lines and found miR-146a induced cells apoptosis. In mechanic analyses, we found that miR-146a inhibited the basal level of Rho-associated, coiled-coil containing protein kinase 1 (ROCK1) expression by targeting its 3'UTR and an inverse correlation of expression between miR-146a and ROCK1 was observed. Moreover, caspase 3 activity was stimulated by miR-146a overexpression., Conclusion: miR-146a has a critical role in the process of AIPC prostate cancer cells apoptosis through regulation of ROCK/Caspase 3 pathway. Targeting this pathway may be a promising therapeutic strategy for future personalized anti-cancer treatment., (© 2015 Wiley Periodicals, Inc.)

MicroRNAs (miRNAs) play a significant role in tumor development. Recent studies indicate that miRNAs are implicated in prostate cancer (PCa). In this study, we found that miR-19a expression was significantly increased in castration-resistant prostate cancer (CRPC) tissues compared with androgen-dependent prostate cancer (ADPC) tissues. We found that inhibiting the overexpression of miR-19a in CRPC cells suppressed proliferation and increased apoptosis. Additionally, we found that miR-19a repressed BTG1 expression by binding to its 3'-untranslated region. The overexpression of BTG1 in CRPC cells significantly suppressed proliferation and increased apoptosis. We conclude that miR-19a regulates proliferation and apoptosis of CRPC cells by directly targeting the tumor suppressor gene BTG1., (Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.)

Objective: To explore the effect of up-regulation of KA1 subunit of the kainate receptor on endoplasmic reticulum stress (ERS)-induced excitotoxic neurodegeneration in mouse hippocampus., Methods: Seventy adult male KM mice were subjected to microinjections into the hippocampus of kainic acid (KA) or 500, 1000, or 2000 µg/ml tunicamycin (TM). At 1, 2, 3, 4, 5, 8, and 12 h after the injections, the mice were assessed for Bederson scores and sacrificed for FJB staining and immunofluorescence observation of the brain slices., Results: At 3, 4, 5, and 8 h after KA injection and at 4 and 5 h after of 2000 µg/ml TM injection, the mice showed severe central nervous system dysfunction, and FJB staining revealed increased cell death in the hippocampus, where up-regulated expressions of KA1 receptor and ERS marker P-eIF2α were found by immunofluorescence staining (P<0.05)., Conclusion: Microinjection of KA or TM into the hippocampus causes neuronal death and ERS with up-regulated expression of KA1. In this process of neuronal apoptosis, the membrane receptor KA1 receives the apoptosis signal and transfers it to the inside of the cells to cause cell endoplasmic reticulum dysfunction and ERS response, which ultimately leads to neuronal death.

Excessive manganese (Mn) exposure can lead to oxidative injury. Nuclear factor erythroid 2-related factor 2 (Nrf2) exerts an antioxidant response toward various environmental toxicants in the brain. However, the role of Nrf2 against Mn-induced oxidative injury remains largely unexplored. This study investigated the role of melatonin (MLT), an agent that was recently shown to induce the activation of the Kelch-like ECH-associated protein 1 (Keap1)-Nrf2-antioxidant response elements (ARE) pathway against manganism. Mice were randomly divided into six groups, including control, 12.5, 25, 50 mg/kg MnCl2, MLT control, and MLT + 50 mg/kg MnCl2. The following were determined: behavioral activity; pathological changes; immunofluorescence staining of Neuronal Nuclei and glial fibrillary acidic protein; cell apoptosis; the levels of reactive oxygen species (ROS), malondialdehyde (MDA), and glutathione (GSH); the immunohistochemical expression; and the protein levels of Nrf2, Keap1, and downstream enzymes. Mn-induced motor disorders, pathological damage, neuron degeneration, astrocytes activation, apoptosis, ROS and MDA generation, and GSH depletion. Nrf2, keap1, heme oxygenase-1 and NAD(P)H dehydrogenase, and quinone 1 showed a biphasic expression trend, which was most evidenced in the 12.5 mg/kg MnCl2 group. Changes in γ-glutamylcysteine synthetase, glutathione peroxidase 1, glutathionine S-transferase, glutathione reductase, and superoxide dismutase decreased in a concentration-dependent manner as a result of Mn exposure. MLT antagonized oxidative injury through the activation of the Keap1-Nrf2-ARE signaling pathway. In conclusion, disturbance of the Keap1-Nrf2-ARE signaling pathway partly caused oxidative injury. MLT can activate Nrf2 and its downstream enzymes and reverse Mn-induced oxidative injury.

Background & Aims: Apoptosis mediated by p53 plays a pathological role in the progression of hepatosteatosis. It is noteworthy that p53 can promote the expression of damage-regulated autophagy modulator (DRAM), an inducer of autophagy-mediated apoptosis. However, the relationship between p53-mediated apoptosis and autophagy in hepatosteatosis remains elusive. This study aimed to examine how p53 orchestrates autophagy and apoptosis to affect hepatosteatosis., Methods: HepG2 cells were treated with oleic acid (OA) for 24 h to induce hepatosteatosis. Mice were fed a high-fat diet for 20 or 40 weeks to induce hepatosteatosis., Results: OA induced a dose-dependent increase in steatosis severity and apoptosis. OA also induced autophagy, which was a critical inducer of apoptosis in mild steatosis induced by 400 μM OA, but not in the more severe steatosis induced by 800 and 1200 μM OA. p53 inhibition by siRNA mostly blocked OA-induced apoptosis and autophagy. Moreover, OA-induced autophagy was DRAM-dependent and primarily occurred in the mitochondria (mitophagy), where DRAM was localized. In severe steatosis induced by 1200 μM OA, apoptosis was mainly dependent on p53-induced expression of BAX, which was also localized to the mitochondria. Our in vivo study showed that p53 expression increased in both mild and severe hepatosteatosis. Increased DRAM expression and autophagy were identified in mild hepatosteatosis, whereas greater BAX expression was observed in severe hepatosteatosis., Conclusions: p53 may induce apoptosis via different mechanisms. DRAM-mediated mitophagy is a primary apoptotic inducer in mild hepatosteatosis, whereas p53-induced BAX expression mainly induces apoptosis in severe hepatosteatosis.

Cancer targeting gene-viro-therapy (CTGVT) may prove to be an effective treatment for pancreatic cancer (PC). This study was intended to explore the anti-tumor effect of ZD55-IL-24 (oncolytic adenovirus ZD55 harboring IL-24) on PC in immune-competent mice. The expression of gene harbored by oncolytic adenovirus ZD55 in PC cells was detected by reporter-gene assays. The in vitro anti PC ability of ZD55-IL-24 was tested by MTT, crystal violet staining and apoptosis assays. The in vivo anti PC effect of ZD55-IL-24 was further observed in an immune-competent mice model by detecting anti-tumor immunity and induction of apoptosis. The expression of gene harbored by ZD55 in PC cells was significantly higher than that harbored by the replicated-deficient adenovirus, and the amount of gene expression was time-dependent and dose-dependent. Both ZD55-IL-24 and ZD55 inhibited PC cells growth, but the anti-tumor effect of ZD55-IL-24 was significantly stronger than that of ZD55, and the ability of ZD55-IL-24 in inducing PC apoptosis was significantly stronger than that of ZD55. The tumor-forming rate of group ZD55-IL-24 was the lowest, and the tumor-growing rate was also significantly lower than that of group ZD55 in immune-competent PC models. Moreover, ZD55-IL-24 mediated more anti-cancer immunity effects by induction of stronger T-lymphocytes response to PC cells, higher levels of γ-IFN and IL-6 cytokines. ZD55-IL-24-mediated CTGVT could inhibit PC growth not only by inducing oncolysis and apoptosis but enhancing the anti-cancer immune effects by inducing T cell response to PC and up-regulating γ-IFN and IL-6 cytokine in immune-competent mice. This may serve as a candidate therapeutic approach for the treatment of PC.

Occupational or environmental exposure to excessive Mn would cause manganism, which is resembled Parkinson disease. However, the mechanism underlying manganism is still unknown. It had been documented that astrocytes play important roles in physiological function in brain. Therefore, in the present study, the cultured astrocytes were exposed to 0, 125, 250, and 500 μM MnCl(2), and cell viability, lactate dehydrogenase (LDH) leakage, morphological change, cell cycle progression, and apoptosis were determined. In addition, 100 μM riluzole (a glutamatergic modulator) was pretreated for 6 h before no MnCl(2) exposure or 500 μM MnCl(2) exposure. The results showed that cell viability inhibited, LDH leakage elevated, morphology injured, G(0)/G(1) phase cell cycle arrested, and apoptosis rate increased in a concentration-dependent manner. Further investigation indicated that riluzole pretreatment reversed cytotoxicity, cell cycle aberration, and apoptosis on astrocytes caused by MnCl(2). These results suggested that MnCl(2) could cause cytotoxicity, cell cycle arrest, and apoptosis concentration-dependently; riluzole might antagonize Mn toxicity on astrocytes.

Androgen-independent prostate cancers express high levels of Bcl-2, and this over-expression of Bcl-2 protects prostate cancer cells from undergoing apoptosis. Ursolic acid (UA) has demonstrated an anti-proliferative effect in various tumor types. The aim of this study is to evaluate the difference between UA-induced apoptosis in androgen-dependent prostate cancer cell line LNCaP cells and androgen-independent prostate cancer cell line LNCaP-AI cells and to reveal the molecular mechanisms underlying the apoptosis. We found that UA treatment in vitro can effectively induce apoptosis in LNCaP and LNCaP-AI cells. UA can overcome Bcl-2-mediated resistance to apoptosis in LNCaP-AI cells. Intrinsic apoptotic pathways can be triggered by UA treatment because c-Jun N-terminal kinase (JNK) is activated and subsequently provokes Bcl-2 phosphorylation and degradation, inducing activation of caspase-9. Although further evaluation is clearly needed, the present results suggest the potential utility of UA as a novel therapeutic agent in advanced prostate cancer., ((c) 2009 Wiley-Liss, Inc.)

Objective: Programmed death-1 (PD-1) up-regulation can impair virus-specific CD8(+) T-cell responses during chronic viral infection. Whether PD-1 affects virus-specific CD8 T cells in humans with acute hepatitis B virus (HBV) infection remains unknown. This study aimed to characterize the PD-1 expression during acute hepatitis B (AHB), and further addressed how PD-1 regulates the apoptosis of CD8(+) T cells in this disease., Methods: PD-1 expression on HBV env-183-191-, env-335-343- and CMV pp65-specific CD8(+) T cells were quantitatively analyzed by flow cytometry in peripheral blood from 15 HLA-A2-positive AHB patients. The spontaneous apoptosis indicated by annexin V expression was performed for analyses of the impact of PD-1 expression. We also confirmed the effects of PD-1/PD-L1 pathway on the in vitro apoptosis of CD8(+) T cells through PD-1 blockade assay., Results: PD-1 expression on HBV-specific CD8(+) T cells was significantly up-regulated compared with CMV-specific CD8(+) T cells in the early phase of acute HBV infection. High levels of PD-1 expression significantly correlated with the apoptosis of HBV-specific CD8(+) T cells. Blockade of PD-1 ligation using anti-PD-L1 rescued the HepG2.215-induced CD8(+) T cell apoptosis., Conclusion: PD-1/PD-L1 inhibitory pathway is actively involved in the apoptotic regulation of HBV-specific CD8(+) T cells at early phase of acute HBV infection, and high PD-1 expression by HBV-specific CD8(+) T cells appear to efficiently temper liver damage.

Lymphoma is one of the most common types of hematological malignancies and proteins from the Bcl-2 family are highly expressed in human lymphomas. Apogossypolone (ApoG2), the most potent gossypol derivative, has been classified as a novel small-molecule inhibitor of antiapoptotic Bcl-2 family proteins. Here, we assessed the in-vitro cytotoxicity of ApoG2 on human U937 lymphoma cells, and explored the underlying intracellular molecular mechanisms of ApoG2. Using the WST-8 assay, we found that ApoG2 inhibited growth of U937 cells in a dose-dependent and time-dependent manner, and the IC50 values were 30.08, 14.81, and 9.26 mumol/l for 24, 48, and 72 h treatments, respectively. ApoG2 also induced apoptosis in U937 cells, as noted through changes in morphological characteristics, including cellular internucleosomal DNA fragmentation and the appearance of a sub-G1 apoptotic peak. Treatment with ApoG2 downregulated Bcl-xL and Mcl-1 protein expression and blocked the binding of Bcl-2 with Bax protein. Furthermore, ApoG2 led to an abundant release of cytochrome c from mitochondria and a five-fold increase in the activity of caspase-3 and caspase-9. Taken together, our results suggest that ApoG2 could effectively suppress the growth of human lymphoma cell line U937 through the inhibition of the antiapoptotic Bcl-2 family proteins and the induction of mitochondria-dependent apoptotic cell death.

cis-Diamminedichloroplatinum (CDDP), commonly know as cisplatin, is a well known DNA-damaging agent, which is highly active in suppressing the proliferation of tumor cells. However, it is not clear that CDDP can induce growth inhibition of esophagus cancer cells. Using the cell line EC-109 from the esophagus, we found that CDDP would induce apoptotic responses. The addition of CDDP to cells led to the inhibition of growth in a time- and dose-dependent manner. CDDP generated reactive oxygen species (ROSs) in cells, which brought about a reduction in the intracellular mitochondrial transmembrane potential (Deltapsim), leading to apoptosis. Our findings demonstrate that ROSs, and the resulting oxidative stress, play a pivotal role in apoptosis. Preincubation of EC-109 cells with the hydrogen-peroxide-scavenging enzyme catalase partially inhibited the following: (i) the production of ROS; (ii) the disruption of the Deltapsim; and (iii) apoptosis. These results indicate that the enhancement of the generation of ROS and the disruption of Deltapsim are events involved in the apoptotic pathway of EC-109 induced by CDDP.

Background & Objective: Reactive oxygen species (ROS), in vivo oxygen metabolites and important signaling molecules, play a vital role in cell apoptosis. This study was to investigate the role of ROS in cisplatin (DDP)-induced apoptosis of esophageal cancer cell line EC-109, and explore the mechanism., Methods: EC-109 cells were treated with different concentrations (0, 1, 5, 10, and 15 microg/ml) of DDP. MTT assay was used to evaluate the influence of DDP on cell proliferation. Flow cytometry was used to test ROS levels, intracellular mitochondrial transmembrane potential (Delta psi m), and hypodiploid apoptosis peak in EC-109 cells. Cell apoptosis after pretreatment with hydrogen peroxide-scavenging enzyme catalase (CAT) was also detected., Results: DDP obviously suppressed proliferation of EC-109 cells. When treated with 0, 1, 5, 10, 15 microg/ml of DDP for 2 h, ROS levels were (3.3+/-1.0)%, (21.6+/-2.0)%, (32.6+/-3.2)%, (44.7+/-2.2)%, and (53.1+/-3.6)%, respectively; when treated for 12 h, Delta psi m were (97.2+/-1.9)%, (90.6+/-1.9)%, (85.5+/-1.4)%, (67.8+/-2.0)%, and (62.4+/-3.0)%, respectively; when treated for 24 h, cell apoptotic rates were (3.4+/-1.2)%, (16.2+/-2.3)%, (28.1+/-1.5)%, (33.2+/-3.9)%, and (45.5+/-3.8)%, respectively. Pretreatment with CAT significantly rescued cells from apoptosis (P<0.05)., Conclusion: DDP generates ROS in esophageal cancer EC-109 cells, which causes mitochondrial membrane permeabilization and Delta psi m decrease, therefore, leads to apoptosis of EC-109 cells.

Sonodynamic therapy (SDT) is a cutting-edge method for the biological effects of ultrasound combined with sound-sensitive agents. In recent years, SDT has been a concern of experts and scholars in the oral field, and a series of experimental studies has been carried out. We will introduce the progress of SDT in the field of stomatology from three aspects: the therapeutic mechanism of SDT, the application of SDT in the oral field, and the current situation and future of SDT in the treatment of oral diseases. It is currently believed that singlet oxygen theory, cavitation effects, and induction of apoptosis are the main therapeutic mechanisms. The research of SDT on oral disease prevention mainly focuses on oral tumors (especially squamous cell carcinoma and osteosarcoma) and infectious diseases (such as periodontitis, maxillofacial infection, and oral mucosal disease). Although the current research is still in the experimental stage, with the continuous exploration of sonosensitizers and nanotechnology, SDT will provide great help for the clinical prevention and treatment of oral diseases in the future.

Programed cell death plays a key role in promoting human development and maintaining homeostasis. Ferroptosis is a recently identified pattern of programmed cell death that is closely associated with the onset and progression of neurodegenerative diseases. Ferroptosis is mainly caused by the intracellular accumulation of iron-dependent lipid peroxides. The cysteine/glutamate antibody Solute carrier family 7 member 11 (SLC7A11, also known as xCT) functions to import cysteine for glutathione biosynthesis and antioxidant defense. SLC7A11 has a significant impact on ferroptosis, and inhibition of SLC7A11 expression promotes ferroptosis. Moreover, SLC7A11 is also closely associated with neurodegenerative diseases. In this paper, we summarize the relationship between ferroptosis and neurodegenerative diseases and the role of SLC7A11 during this process. The various regulatory mechanisms of SLC7A11 are also discussed. In conclusion, we are looking forward to a theoretical basis for further understanding the occurrence and development of ferroptosis in SLC7A11 and neurodegenerative diseases, and to seek new clues for the treatment of neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Objective: Photosensitivity is one of the most common manifestations of systemic lupus erythematosus (SLE), yet its pathogenesis is not well understood. The normal‐appearing epidermis of patients with SLE exhibits increased ultraviolet B (UVB)–driven cell death that persists in cell culture. Here, we investigated the role of epigenetic modification and Hippo signaling in enhanced UVB‐induced apoptosis seen in SLE keratinocytes. Methods: We analyzed DNA methylation in cultured keratinocytes from SLE patients compared to keratinocytes from healthy controls (n = 6/group). Protein expression was validated in cultured keratinocytes using immunoblotting and immunofluorescence. An immortalized keratinocyte line overexpressing WWC1 was generated via lentiviral vector. WWC1‐driven changes were inhibited using a large tumor suppressor kinase 1/2 (LATS1/2) inhibitor (TRULI) and small interfering RNA (siRNA). The interaction between the Yes‐associated protein (YAP) and the transcriptional enhancer associate domain (TEAD) was inhibited by overexpression of an N/TERT cell line expressing a tetracycline‐inducible green fluorescent protein–tagged protein that inhibits YAP–TEAD binding (TEADi). Apoptosis was assessed using cleaved caspase 3/7 and TUNEL staining. Results: Hippo signaling was the top differentially methylated pathway in SLE versus control keratinocytes. SLE keratinocytes (n = 6) showed significant hypomethylation (Δβ = −0.153) and thus overexpression of the Hippo regulator WWC1 (P = 0.002). WWC1 overexpression increased LATS1/2 kinase activation, leading to YAP cytoplasmic retention and altered proapoptotic transcription in SLE keratinocytes. Accordingly, UVB‐mediated apoptosis in keratinocytes could be enhanced by WWC1 overexpression or YAP–TEAD inhibition, mimicking SLE keratinocytes. Importantly, inhibition of LATS1/2 with either the chemical inhibitor TRULI or siRNA effectively eliminated enhanced UVB‐apoptosis in SLE keratinocytes. Conclusion: Our work unravels a novel driver of photosensitivity in SLE: overactive Hippo signaling in SLE keratinocytes restricts YAP transcriptional activity, leading to shifts that promote UVB apoptosis. [ABSTRACT FROM AUTHOR]

Methylmercury (MeHg) is a cumulative environmental pollutant that can easily cross the blood–brain barrier and cause damage to the brain, mainly targeting the central nervous system. The purpose of this study is to investigate the role of calcium ion (Ca2+) homeostasis between the endoplasmic reticulum (ER) and mitochondria in MeHg‐induced neurotoxicity. Rat primary cortical neurons exposed to MeHg (0.25–1 μm) underwent dose‐dependent cell damage, accompanied by increased Ca2+ release from the ER and elevated levels of free Ca2+ in cytoplasm and mitochondria. MeHg also increased the protein and messenger RNA expressions of the inositol 1,4,5‐triphosphate receptor, ryanodine receptor 2, and mitochondrial calcium uniporter. Ca2+ channel inhibitors 2‐aminoethyl diphenylborinate and procaine reduced the release of Ca2+ from ER, while RR and 4,4′‐diisothiocyanatostilbene‐2,2′‐disulfonate inhibited Ca2+ uptake from mitochondria. In addition, pretreatment with Ca2+ chelator BAPTA‐AM effectively restored mitochondrial membrane potential levels, inhibited over opening of mitochondrial permeability transition pore, and maintained mitochondrial function stability. Meanwhile, the expression of mitochondrial apoptosis‐related proteins recovered to some extent, along with the reduction of the early apoptosis ratio. These results suggest that Ca2+ homeostasis plays an essential role in mitochondrial damage and apoptosis induced by MeHg, which may be one of the important mechanisms of MeHg‐induced neurotoxicity. [ABSTRACT FROM AUTHOR]

Background: Osteoclast cell increase is a major risk factor for osteoporosis and degenerative bone and joint diseases. At present, RANKL and M-CSF are commonly used to induce osteoclastogenesis. Thioacetamide (TAA) can lead to many types of liver and kidney damage, but less attention has been paid to the association of TAA with bone damage. In this work, we investigated the effects of TAA on the osteoclastogenesis and differentiation of bone marrow macrophages (BMMs). Methods: BMMs of SD rat suckling mice were taken for primary culture. CCK-8 was used to detect the toxic effects of TAA on BMMs, and flow cytometry was used to detect the effects of TAA on the cell cycle, cell viability, apoptosis and intracytoplasmic Ca2+ concentration of BMMs. TRAP staining was used to detect the effect of RANKL and M-CSF and TAA on osteoclast differentiation of BMMs. Western Blot was used to detect the expression level of PI3K/AKT pathway and osteoclast-specific proteins (TRAP and cathepsin K). Results: The results suggested that TAA inhibited the proliferation of BMMs, while enhancing osteoclastogenesis at 0.5 mg/mL and 1 mg/mL as assayed by TRAP staining. Exposed to TAA, BMMs could differentiate into osteoclast-like cells with overexpression of cathepsin K and TRAP proteins. Western blot results showed that TAA can activate the expression levels of P-PI3K, P-AKT, P-P38, and P-JNK, accompanied by apoptosis of BMMs and increase in intracellular Ca2+. Conclusion: TAA may induce osteoclast formation in BMMs by activating the expression of PI3K/AKT pathway proteins, which is comparable to the classic osteoclast differentiation inducer RANKL and M-CSF. This suggests that we may find a cheap osteoclast inducer. [ABSTRACT FROM AUTHOR]

Summary: G-quadruplexes (G4s) are DNA or RNA structures formed by guanine-rich repeating sequences. Recently, G4s have become a highly attractive therapeutic target for BRCA-deficient cancers. Here, we show that a substituted quinolone amide compound, MTR-106, stabilizes DNA G-quadruplexes in vitro. MTR-106 displayed significant antiproliferative activity in homologous recombination repair (HR)-deficient and PARP inhibitor (PARPi)-resistant cancer cells. Moreover, MTR-106 increased DNA damage and promoted cell cycle arrest and apoptosis to inhibit cell growth. Importantly, its oral and i.v. administration significantly impaired tumor growth in BRCA-deficient xenograft mouse models. However, MTR-106 showed modest activity against talazoparib-resistant xenograft models. In rats, the drug rapidly distributes to tissues within 5 min, and its average concentrations were 12-fold higher in the tissues than in the plasma. Overall, we identified MTR-106 as a novel G-quadruplex stabilizer with high tissue distribution, and it may serve as a potential anticancer agent. [ABSTRACT FROM AUTHOR]

Cold stress is one of the serious factors restricting the development of animal husbandry in cold areas. Cold exposure can easily lead to cold stress, slow growth and even death of newborn animals. O -GlcNAcylation modification can act as type of "stress receptor" and"nutrition sensor" in a variety of stress responses, however, it is not clear how O -GlcNAcylation can regulate glucose metabolism in the liver of piglets under cold stress. In this study, piglets 21 days of age were exposed to 4 °C for 4 h or 8 h in a phytotron. Serum cortisol and other stress hormones were used to assess body status to establish a cold stress piglet model. The changes of glycogen in liver were detected by PAS. FDP and PA were also measured to study the glycolysis level of liver. To characterize potential mechanisms of O -GlcNAcylation on the livers of cold stress piglets, AKT, GSK3β, GS, PFKFB2, AS160 and their corresponding phosphorylation were determined by Western blotting. Results show O -GlcNAcylation increased and apoptosis levels increased in the liver following cold exposure during excessive CORT or metabolic dysfunction. It is suggested that the acute cold exposure of piglets induced a sequential change in the level of O -GlcNAcylation, which may be one of the factors mediating liver cell apoptosis and glucose metabolism regulation by the O -GlcNAc/AKT pathway. These findings provide new insight into the mechanisms of the cold stress response, which can facilitate the development of new strategies to combat the effects of hypothermia. [ABSTRACT FROM AUTHOR]