Super enhancer-driven core transcriptional regulatory circuitry crosstalk with cancer plasticity and patient mortality in triple-negative breast cancer.

Triple-negative breast cancer (TNBC) is a clinically aggressive subtype of breast cancer. Core transcriptional regulatory circuitry (CRC) consists of autoregulated transcription factors (TFs) and their enhancers, which dominate gene expression programs and control cell fate. However, there is limited knowledge of CRC in TNBC. Herein, we systemically characterized the activated super-enhancers (SEs) and interrogated 14 CRCs in breast cancer. We found that CRCs could be broadly involved in DNA conformation change, metabolism process, and signaling response affecting the gene expression reprogramming. Furthermore, these CRC TFs are capable of coordinating with partner TFs bridging the enhancer-promoter loops. Notably, the CRC TF and partner pairs show remarkable specificity for molecular subtypes of breast cancer, especially in TNBC. USF1, SOX4, and MYBL2 were identified as the TNBC-specific CRC TFs. We further demonstrated that USF1 was a TNBC immunophenotype-related TF. Our findings that the rewiring of enhancer-driven CRCs was related to cancer immune and mortality, will facilitate the development of epigenetic anti-cancer treatment strategies.

Study of the influence of meteorological factors on HFMD and prediction based on the LSTM algorithm in Fuzhou, China.

BACKGROUND: This study adopted complete meteorological indicators, including eight items, to explore their impact on hand, foot, and mouth disease (HFMD) in Fuzhou, and predict the incidence of HFMD through the long short-term memory (LSTM) neural network algorithm of artificial intelligence. METHOD: A distributed lag nonlinear model (DLNM) was used to analyse the influence of meteorological factors on HFMD in Fuzhou from 2010 to 2021. Then, the numbers of HFMD cases in 2019, 2020 and 2021 were predicted using the LSTM model through multifactor single-step and multistep rolling methods. The root mean square error (RMSE), mean absolute error (MAE), mean absolute percentage error (MAPE) and symmetric mean absolute percentage error (SMAPE) were used to evaluate the accuracy of the model predictions. RESULTS: Overall, the effect of daily precipitation on HFMD was not significant. Low (4 hPa) and high (≥ 21 hPa) daily air pressure difference (PRSD) and low (< 7 °C) and high (> 12 °C) daily air temperature difference (TEMD) were risk factors for HFMD. The RMSE, MAE, MAPE and SMAPE of using the weekly multifactor data to predict the cases of HFMD on the following day, from 2019 to 2021, were lower than those of using the daily multifactor data to predict the cases of HFMD on the following day. In particular, the RMSE, MAE, MAPE and SMAPE of using weekly multifactor data to predict the following week's daily average cases of HFMD were much lower, and similar results were also found in urban and rural areas, which indicating that this approach was more accurate. CONCLUSION: This study's LSTM models combined with meteorological factors (excluding PRE) can be used to accurately predict HFMD in Fuzhou, especially the method of predicting the daily average cases of HFMD in the following week using weekly multifactor data.

Study on the influence of meteorological factors on influenza in different regions and predictions based on an LSTM algorithm.

BACKGROUND: Influenza epidemics pose a threat to human health. It has been reported that meteorological factors (MFs) are associated with influenza. This study aimed to explore the similarities and differences between the influences of more comprehensive MFs on influenza in cities with different economic, geographical and climatic characteristics in Fujian Province. Then, the information was used to predict the daily number of cases of influenza in various cities based on MFs to provide bases for early warning systems and outbreak prevention. METHOD: Distributed lag nonlinear models (DLNMs) were used to analyse the influence of MFs on influenza in different regions of Fujian Province from 2010 to 2021. Long short-term memory (LSTM) was used to train and model daily cases of influenza in 2010-2018, 2010-2019, and 2010-2020 based on meteorological daily values. Daily cases of influenza in 2019, 2020 and 2021 were predicted. The root mean squared error (RMSE), mean absolute error (MAE), mean absolute percentage error (MAPE) and symmetric mean absolute percentage error (SMAPE) were used to quantify the accuracy of model predictions. RESULTS: The cumulative effect of low and high values of air pressure (PRS), air temperature (TEM), air temperature difference (TEMD) and sunshine duration (SSD) on the risk of influenza was obvious. Low (< 979 hPa), medium (983 to 987 hPa) and high (> 112 hPa) PRS were associated with a higher risk of influenza in women, children aged 0 to 12 years, and rural populations. Low (< 9 °C) and high (> 23 °C) TEM were risk factors for influenza in four cities. Wind speed (WIN) had a more significant effect on the risk of influenza in the ≥ 60-year-old group. Low (< 40%) and high (> 80%) relative humidity (RHU) in Fuzhou and Xiamen had a significant effect on influenza. When PRS was between 1005-1015 hPa, RHU > 60%, PRE was low, TEM was between 10-20 °C, and WIN was low, the interaction between different MFs and influenza was most obvious. The RMSE, MAE, MAPE, and SMAPE evaluation indices of the predictions in 2019, 2020 and 2021 were low, and the prediction accuracy was high. CONCLUSION: All eight MFs studied had an impact on influenza in four cities, but there were similarities and differences. The LSTM model, combined with these eight MFs, was highly accurate in predicting the daily cases of influenza. These MFs and prediction models could be incorporated into the influenza early warning and prediction system of each city and used as a reference to formulate prevention strategies for relevant departments.

Cadmium disrupts mouse embryonic stem cell differentiation into ovarian granulosa cells through epigenetic mechanisms.

Cadmium (Cd) can influence germ cell development, and epigenetic events may be involved. However, there is no study on whether Cd can influence germ cells differentiation into ovarian granulosa cells (GCs), and more insight into the molecular mechanism of the effect of Cd on germ cell development from mouse embryonic stem (ES) cells into ovarian granulosa cells and investigation of appropriate epigenetic factors are of great importance. In this study, mouse ES cell differentiation into GCs was established in an in vitro model. Subsequently, different Cd concentrations of 0, 0.1, 0.3, and 1 and then 3.0, and 10.0 µmol/L were cultured in this in vitro model. We demonstrated that Cd treatment can interrupt ES cell differentiation into GCs by morphology and ultrastructure observation. Four specific markers (octamer-binding transcription factor 4 (OCT4), sex-determining region Y-box 2 (SOX2), Nanog homeobox (Nanog), and Anti-müllerian hormone type II receptor (Amhr2)) were significantly changed as measured by quantitative real-time-PCR or Western blot (p < 0.05). Cd also significantly changed the DNA methylation of GC sites on the CpG island of Nanog according to the sequential mass ARRAYR methylation method (p < 0.05). The MeRIP-qPCR method was used to detect the levels of N6-methyladenosine (m6A) methylation modification of long noncoding RNA (lncRNA) 1281 and indicated that they were decreased (p < 0.05). Microarray chip analysis, miRNA screening, and bioinformatics were used to further explore the roles of marker regulation-related miRNAs, and 27 miRNAs were putatively related to Cd-interrupted differentiation in ES cells. These data indicated that Cd can interrupt ES cell differentiation into GCs and affect germ cell development, and the underlying mechanism may involve epigenetic mechanisms.

Left ventricular long-axis ultrasound strain (GLS) is an ideal indicator for patients with anti-hypertension treatment.

BACKGROUND: Primary hypertension is one of the most well-known risk factors for cardiovascular disease. Currently, there is still no ideal indicator for left ventricular end-diastolic pressure. METHODS: 73 hypertension patients and 37 healthy people were enrolled in this study. Each member was examined with conventional echocardiography including multiple indicators such as Peak mitral valve flow velocity (E, A), E/A, left atrial volume index (LAVl), tissue Doppler (PW-TDI) peak velocities during early and late diastolic mitral valve flow (e '), E/e ', and GLS. We have collected clinical data from all enrolled members. The above cardiac ultrasound indicators were obtained before the antihypertensive treatment, one month and three months after treatment. RESULTS: Left ventricular end-diastolic pressure (LVEDP) was positively correlated and negatively correlated with GLS (r = 0.638, P < .01) and E/e' (r = -0.578, P < .05), respectively. The hypertensives had lower e' value and higher values of GLS, E/e', and LAVI than the control group (P < .05). GLS and E/e' were significantly lower in hypertension group than those in the Control group after one month and three months of treatment (P < .05). The improvement rate of GLS was significantly higher than those in the improvement rate of e', E/e', LAVI after treatment (p < .05). CONCLUSION: The GLS improvement rate was significantly higher than those of e', E/e' after one and three-month treatment. Therefore, GLS might be a potential ideal index for patients with anti-hypertension treatment. The results obtained in this study provide useful information for further study.

C-myc promotes miR-92a-2-5p transcription in rat ovarian granulosa cells after cadmium exposure.

Cadmium (Cd) can induce ovarian injury by microRNAs (miRNAs), however, the molecular mechanism of miRNAs after Cd exposure have not known. In this study, 56-day-old adult female Sprague-Dawley (SD) rats were injection with PMSG, after 48 h, ovarian granulosa cells (GCs) were extracted and cultured for 24 h, then treated with 0, 2.5, 5, 10 and 20 µM Cd for 24 h. The results showed that expression levels of miR-92a-2-5p (upregulated) and Bcl2 (downregulated) changed significantly after Cd exposure. The messenger RNA (mRNA) and protein expression levels of DNMT1, DNMT3A, and DNMT3B had changed, but no obvious differences were found in miR-92a-2-5p single site methylation. The transcription factors C-MYC (upregulated), E2F1 (downregulated), and SP1 (downregulated), which target miRNAs significantly changed after exposure to Cd. The human ovarian GC tumor line (COV434) was used to knocked down C-myc, and the expression of miR-92a-2-5p was downregulated in the COV434-C-myc + 10 µM Cd group compared with COV434 cells. The N6-methyladenosine (m6A) methylation modification levels of long noncoding RNA (lncRNA) MT1JP and lncRNA CDKN2B-AS, which regulate miR-92a-2-5p were detected. In the 10 µM Cd group, m6A methylation levels at MT1JP-84, CDKN2B-AS-257, and CDKN2B-AS-329 were reduced. In summary, after Cd exposure, expression of miR-92a-2-5p, which targets the antiapoptotic gene Bcl2, was upregulated, which may be primarily related to upregulation of C-myc. MiR-92a-2-5p promoter DNA methylation may has no obvious effect on miR-92a-2-5p. Otherwise, the role of m6A methylation modified lncRNA MT1JP and lncRNA CDKN2B-AS in the regulation of miR-92a-2-5p needs further study.

Graphene quantum dots wrapped square-plate-like MnO2 nanocomposite as a fluorescent turn-on sensor for glutathione.

Benefiting from their excellent optical absorption and electron transfer properties, manganese dioxide nanomaterials have been widely applied for fluorescence-based nanosensors. In this work, graphene quantum dots (GQDs) wrapped square-plate-like MnO2 nanocomposite was synthesized from potassium permanganate via an in situ redox procedure under ultrasonication with poly(allylamine hydrochloride) (PAH) being involved. Through an effective fluorescence resonance energy transfer (FRET) process and inner filter effect (IFE) between GQDs and MnO2, the fluorescence of GQDs was quenched. Furthermore, the introduction of glutathione (GSH) decomposed MnO2 and caused fluorescence recovery of GQDs. Therefore, a MnO2 mediated nanosensor was established for fluorescent turn-on sensing of GSH. A satisfactory linear range was found to be 0.07-70 µM and the detection limit was as low as 48 nM. Besides, the fluorescent recognition of cancer cells using GQDs-MnO2 nanocomposite was achieved because of the obviously higher GSH content in cancer microenvironment than normal cells. This nanosensor was constructed directly in GQDs solution in the presence of PAH without the complicated modifications or connections, making it a facile and novel nanosensor for GSH.

Isolation of a human monoclonal antibody specific for the receptor binding domain of SARS-CoV-2 using a competitive phage biopanning strategy.

The infection of the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused more than 200 000 deaths, but no vaccine or therapeutic monoclonal antibody is currently available. SARS-CoV-2 relies on its spike protein, in particular the receptor-binding domain (RBD), to bind human cell receptor angiotensin-converting enzyme 2 (ACE2) for viral entry, and thus targeting RBD holds the promise for preventing SARS-CoV-2 infection. In this work, a competitive biopanning strategy of a phage display antibody library was applied to screen blocking antibodies against RBD. High-affinity antibodies were enriched after the first round using a standard panning process in which RBD-His was immobilized as a bait. At the next two rounds, immobilized ACE2-Fc and free RBD-His were mixed with the enriched phage antibodies. Antibodies binding to RBD at epitopes different from ACE2-binding site were captured by the immobilized ACE2-Fc, forming a "sandwich" complex. Only antibodies competed with ACE2 can bind to the free RBD-His in the supernatant and be subsequently separated by the nickel-nitrilotriacetic acid magnetic beads. rRBD-15 from the competitive biopanning of our synthetic antibody library, Lib AB1, was produced as the full-length IgG1 format. It was proved to competitively block the binding of RBD to ACE2 and potently inhibit SARS-CoV-2 pseudovirus infection with IC50 values of 12 nM. Nevertheless, rRBD-16 from the standard biopanning can only bind to RBD in vitro, but not have the blocking or neutralization activity. Our strategy can efficiently isolate the blocking antibodies of RBD, and it would speed up the discovery of neutralizing antibodies against SARS-CoV-2.

A graphene quantum dots-Pb2+ based fluorescent switch for selective and sensitive determination of D-penicillamine.

Taking consideration of metal-induced fluorescence quenching and excellent coordination effect of D-penicillamine (D-PA), a graphene quantum dots (GQDs)-based fluorescent switch for D-PA detection was designed and established firstly with the help of lead ions. GQDs obtained from citric acids made them rich in carboxyl and hydroxyl groups, giving GQDs the ability to combine with lead ions. As anticipated, the fluorescence intensity was quenched by Pb2+ through electron transfer process. Further, the addition of D-PA effectively recovered the fluorescence due to the departure of Pb2+ from GQDs aroused by the strong coordination between D-PA and Pb2+. Thus, a fluorescent switch was activated for D-PA detection. The fluorescence recovery efficiencies were found to be proportional to the concentration of D-PA in the range of 0.6-50 µmol L-1 and the detection limit was 0.47 µmol L-1. The real sample detection was performed in human urea sample and satisfactory recoveries of 96.84%-102.13% were obtained. The GQDs-Pb2+ based fluorescent switch sensing method was firstly established with low detection limit and wide linear range, making it a supplement and improvement for D-PA detection.

Surface effects on the self equilibrium, self bending and symmetry lowering of nanofilms.

A continuum theoretical scheme for self equilibrium, self bending and symmetry lowering of nanofilms was obtained by considering surface elasticity, surface stress and the corresponding surface slice thickness. When surface stress and surface elasticity are both balance, the nanofilm is simply compressed (or expanded). When the surface stress or surface elasticity is imbalance, the nanofilm will bend. On the other hand, surface stress and surface elasticity imbalances induce a nanofilm to curl into a nanotube when the nanofilm is very thin. The surface stress and surface elasticity balances induce uniform in-plane strain (the overall film relaxation), while the vertical direction of the nanofilm relaxes reversely due to Poisson's effect. And then, the crystal lattice constants of in-plane and vertical directions are different from each other, the ratio of these two lattice constants decrease with film thickness increase. Hence, the symmetry of the nanofilm is lowered by the overall film relaxation.

The Advanced Anaerobic Expanded Granular Sludge Bed (AnaEG) Possessed Temporally and Spatially Stable Treatment Performance and Microbial Community in Treating Starch Processing Wastewater.

This study implements temporal and spatial appraisals on the operational performance and corresponding microbial community structure of a full-scale advanced anaerobic expanded granular sludge bed (AnaEG) which was used to treat low organic loading starch processing wastewater. Results showed stable treatment efficiency could be maintained with long-term erratic influent quality, and a major reaction zone located at the bottom of the AnaEG, where the main pollutant removal rate was greater than 90%. Remarkably, high-throughput sequencing of 16S rRNA gene amplicons displayed that the predominant members constructed the major part of the overall microbial community and showed highly temporal stability. They were affiliated to Chloroflexi (16.4%), Proteobacteria (14.01%), Firmicutes (8.76%), Bacteroidetes (7.85%), Cloacimonetes (3.21%), Ignavibacteriae (1.80%), Synergistetes (1.11%), Thermotogae (0.98%), and Euryarchaeota (3.18%). This part of microorganism implemented the long-term stable treatment efficiency of the reactor. Simultaneously, an extraordinary spatial homogeneity in the granule physic properties and microbial community structure along the vertical direction was observed within the AnaEG. In conclusion, the microbial community structure and the bioreactor's performance showed notable spatial and temporal consistency, and the predominant populations guaranteed a long-term favorable treatment performance of the AnaEG. It provides us with a better understanding of the mechanism of this recently proposed anaerobic reactor which was used in low organic loading wastewater treatment.

MiR-15b-5p Regulates Collateral Artery Formation by Targeting AKT3 (Protein Kinase B-3).

OBJECTIVE: To identify circulating microRNAs that are differentially expressed in severe coronary heart disease with well or poorly developed collateral arteries and to investigate their mechanisms of action in vivo and in vitro. APPROACH AND RESULTS: In our study, we identified a circulating microRNA, miR-15b-5p, with low expression that, nevertheless, characterized patients with sufficient coronary collateral artery function. Moreover, in murine hindlimb ischemia model, in situ hybridization identified that miR-15b-5p was specifically expressed in vascular endothelial cells of adductors in sham group and was remarkably downregulated after femoral artery ligation. Overexpressed miR-15b-5p significantly inhibited arteriogenesis and angiogenesis in mice. In vitro, both under basal and vascular endothelial growth factor stimulation, loss-of-function or gain-of-function studies suggested that miR-15b-5p significantly promoted or depressed the migration and proliferation of endothelial cells. We identified AKT3 (protein kinase B-3) as a direct target of miR-15b-5p. Interestingly, AKT3 deficiency by injection with Chol-AKT3-siRNA obviously suppressed arteriogenesis and the recovery of blood perfusion after femoral ligation in mice. CONCLUSIONS: These results indicate that circulating miR-15b-5p is a suitable biomarker for discriminating between patients with well-developed or poorly developed collaterals. Moreover, miR-15b-5p is a key regulator of arteriogenesis and angiogenesis, which may represent a potential therapeutic target for ischemic disease.

HHEX: A Crosstalker between HCMV Infection and Proliferation of VSMCs.

Objective: The study was designed to evaluate the role of Human cytomegalovirus (HCMV) infection on homebox (HOX) gene expression and the effects of overexpression of HOX genes on proliferation and apoptosis of vascular smooth muscle cells (VSMCs). Methods: Viral infection was verified by observation of cytopathic effects through inverted microscopy, viral particles by electron microscopy and HCMV IE gene amplification by RT-PCR. cDNA profiling technology was used to screen expression of HOX genes after HCMV infection in VSMCs. Abnormal expression of Haematopoietically-expressed homeobox (HHEX) was selected to construct over-expressed vector and transfected into VSMCs. The effects of over expression of HHEX on cell proliferation and apoptosis of VSMCs were assayed by flow cytometry. Apoptosis and proliferation-associated genes were also assayed by RT-PCR. Results: Multiple HOX gene expression levels had obvious changes after HCMV infection, among which expression of HHEX gene increased obviously at 24, 48, and 72 h after infection. Over expression of HHEX can promote VSMCs proliferation by promoting G0/G1 phase cells into S phase and inhibit VSMCs apoptosis. HHEX inhibited the expression of apoptosis-associated caspase 2 and caspase3 and promoted the expression of cell cycle-related genes such as CDK2 and CDK6, CyclinB2 and CyclinD2. Conclusion: HHEX over expression induced by HCMV infection closely associated with vascular proliferative diseases.

Lipid Metabolism in Vascular Smooth Muscle Cells Infuenced by HCMV Infection.

BACKGROUND: The present study was designed to observe the infection of human cytomegalovirus (HCMV) to human vascular smooth muscle cells (VSMCs), and the effect of viral infection on lipid metabolism in VSMCs. METHODS: The cytopathic effects were observed by inverted microscopy and viral infection were examined by electron microscopy and RT-PCR. The lipid metabolism related gene profiling of VSMCs after HCMV infection was assayed by cDNA assay and the abnormal expression of genes were validated by quantitative RT-PCR. The content of cholesterol in VSMCs after HCMV infection was assayed by cholesterol detection kit. RESULTS: VSMCs showed obvious cytopathic effects after HCMV infection. Intact viral particles could be detected in VSMCs using electron microscope. By use of RT-PCR technology, IE gene of HCMV could be amplified from VSMCs. The expression of cell lipid metabolism related gene profiling showed obvious disorders. The expression levels of HMG-CoA synthase and HMG-CoA reductase after infection increased significantly. The cellular cholesterol content (µmol/106 cells) was significantly higher than that of mock infected group at 72h post infection. CONCLUSION: HCMV can infect VSMCs and the infection can affect cellular lipid metabolism related gene expression, which get involved in the occurrence and development of atherosclerosis (AS).

[Preparation and evaluation of pharmacodynamic of the pectin-doxorubicin conjugate nanosuspensions].

This study was conducted to produce pectin-doxorubicin conjugate（PDC） nanosuspensions by high-pressure homogenization, and investigating the physico-chemical properties, the cumulative release rate in vitro and in vivo, and the anti-tumor activity. The major production parameters such as pressure, cycle numbers and types of stabilizers on the mean particle size and polydispersity index（PI） of PDC nanosuspensions were investigated. The cumulative release rate in phosphate buffer saline（PBS） at pH 5.1 or 7.0 were studied. The concentration of doxorubicin（DOX） in plasma of rabbit were recorded after intraperitoneal injection of PDC nanosuspensions(DOX was equivalent to 10 mg·kg-1) or DOX (10 mg·kg-1). We established an animal model of the nude mice with SKOV3 cell, and injected the PDC nanosuspensions(DOX was equivalent to 10, 5, 2.5 mg·kg-1) in the first day, and observed the growth state of nude mice. The particle size of PDC nanosuspensions was 118.8 ± 6.93 nm, PI was 0.14 ± 0.03, as well as the zeta potential was -27.2 ± 0.36 m V. It shows that no drug release was found in PBS at p H 7.4. About 40% cumulative release was determined in PBS at 5.1 after 30 h. The concentration of DOX in plasma of PDC group was 60 ng·mL-1, and was lower than that of DOX group. Compared with control group, high-dose-group decreased the weight of nude mice's ascites tumor and burrknot. PDC nanosuspensions can inhibit the growth of SKOV3 cell line in nude mice.In summary, PDC nanosuspensions are target-specific drugs with high efficiency and low toxicity in the ascites cancer model.

High-Density Lipoprotein Prevents Endoplasmic Reticulum Stress-Induced Downregulation of Liver LOX-1 Expression.

Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is a specific cell-surface receptor for oxidized-low-density lipoprotein (ox-LDL). The impact of high-density lipoprotein (HDL) on endoplasmic reticulum (ER) stress-mediated alteration of the LOX-1 level in hepatocytes remains unclear. We aimed to investigate the impact on LOX-1 expression by tunicamycin (TM)-induced ER stress and to determine the effect of HDL on TM-affected LOX-1 expression in hepatic L02 cells. Overexpression or silencing of related cellular genes was conducted in TM-treated cells. mRNA expression was evaluated using real-time polymerase chain reaction (PCR). Protein expression was analyzed by western blot and immunocytochemistry. Lipid uptake was examined by DiI-ox-LDL, followed by flow cytometric analysis. The results showed that TM induced the upregulation of ER chaperone GRP78, downregulation of LOX-1 expression, and lipid uptake. Knock down of IRE1 or XBP-1 effectively restored LOX-1 expression and improved lipid uptake in TM-treated cells. HDL treatment prevented the negative impact on LOX-1 expression and lipid uptake induced by TM. Additionally, 1-10 µg/mL HDL significantly reduced the GRP78, IRE1, and XBP-1 expression levels in TM-treated cells. Our findings reveal that HDL could prevent the TM-induced reduction of LOX-1 expression via inhibiting the IRE1/XBP-1 pathway, suggesting a new mechanism for beneficial roles of HDL in improving lipid metabolism.

Asymmetric dimethylarginine triggers macrophage apoptosis via the endoplasmic reticulum stress pathway.

Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase (NOS), is emerging as a key contributing factor in atherogenesis, a process in turn known to involve macrophage apoptosis. The aim of this study was to determine the effect of ADMA on macrophage apoptosis, with specific reference to the endoplasmic reticulum (ER) stress pathway. Macrophage apoptosis was evaluated by Annexin V- Propidium iodide (PI) and Hoechst 33258 staining assays. Levels of the ER stress marker glucose regulated protein 78 (GRP78) were characterized by western blot. Levels of the proapoptotic C/EBP-homologous protein (CHOP) were evaluated by western blot and reverse transcription polymerase chain reaction (RT-PCR), and caspase-4 activity was measured using a colorimetric protease assay kit. We observed ADMA dose- and time-dependent increases in macrophage levels of GRP78. Similar ADMA dose- and time-dependent increases were detected in intracellular caspase-4 activity and macrophage apoptosis, all of which were sensitive to treatment with siRNAs for protein kinase RNA-like ER kinase and inositol-requiring protein-1 (IRE1), the ADMA antagonist L-arginine, as well as inhibitors of eukaryotic translation initiation factor-2 (salubrinal), IRE1 (irestatin 9389), and c-Jun N-terminal kinase (SP600125). Our results indicate that ADMA triggers macrophage apoptosis via the ER stress pathway.

Ox-LDL induces endothelial cell apoptosis via the LOX-1-dependent endoplasmic reticulum stress pathway.

OBJECTIVE: To investigate the effect of lectin-like ox-LDL receptor-1 (LOX-1) on oxidized low-density lipoprotein (ox-LDL)-induced apoptosis and the involvement of the endoplasmic reticulum (ER) stress response pathway. METHODS AND RESULTS: Human umbilical vein endothelial cells were treated with 50, 100, or 200 µg/ml ox-LDL and cultured for 12, 24, or 48 h for concentration- and time-dependent studies. Cells were transfected with LOX-1 or Nox-4 shRNAs, and target proteins were inhibited with the corresponding antibodies for mechanistic studies. Active proteins and mRNAs were analyzed by Western blotting and RT-PCR, respectively. Cell apoptosis was analyzed by Annexin and Hoechst staining assays. Ox-LDL induced both apoptosis and protein expression of LOX-1 and Nox-4 through activation of ER stress sensors IRE1 and PERK, and nuclear translocation of ATF6 and their subsequent pathways were indicated by JNK, eukaryotic initiation factor 2 phosphorylation, XBP-1, and chaperone GRP78 expression; up-regulation of proapoptotic proteins CHOP and Bcl-2; and caspase-12 activity. LOX-1 gene silencing and treatment with an anti-LOX-1 antibody attenuated the effects of ox-LDL. Pretreatment with irestatin 9389, salubrinal, or AEBSF also blocked ox-LDL-induced expression of CHOP and Bcl-2 and activation of caspase-12 activity, leading to an attenuation of endothelial cell apoptosis. Furthermore, Nox-4 siRNA attenuated the up-regulated expression of GRP78, PERK, IRE1, and XBP-1 to reduce ox-LDL-induced endothelial cell apoptosis. CONCLUSIONS: LOX-1 plays a critical role in ox-LDL-induced endothelial cell apoptosis via the ER stress pathway.

Adsorption of tetracycline to nano-NiO: the effect of co-existing Cu(ii) ions and environmental implications.

Nano-sized nickel oxide (nano-NiO) is a new nanomaterial that has shown great promise in many areas of application. Understanding its environmental fate and effects is critical for minimizing the potential environmental implications of this new material due to incidental and accidental releases in the future. In this study, we observed strong adsorption of tetracycline to nano-NiO and found that the adsorption affinity can be further enhanced by Cu(ii) ions - the observed distribution coefficient (Kd) values are 10(3.1) to 10(4.2) L kg(-1) in the absence of Cu(ii) and 10(3.0) to 10(5.5) L kg(-1) in the presence of Cu(ii); such adsorption affinities are even comparable to those of tetracycline to carbonaceous materials. The strong adsorptive affinities of nano-NiO for tetracycline are likely attributable to several mechanisms, including surface complexation, cation exchange, and electrostatic attraction. As a strong complexing agent, Cu(ii) can significantly enhance adsorption of tetracycline by serving as a bridging agent between tetracycline and nano-NiO. The findings of this study have important implications for the risk assessment of engineered nanomaterials - in aquatic environments nano-NiO (and likely other metal oxide nanomaterials) can strongly adsorb tetracycline antibiotics, resulting in the changes of environmental risks of the metal oxide nanomaterials and/or bioavailability of the adsorbed contaminants.