Identification of tyrosine brominated extracellular matrix proteins in normal and fibrotic lung tissues.

Peroxidasin (PXDN) is a secreted heme peroxidase that catalyzes the oxidative crosslinking of collagen IV within the extracellular matrix (ECM) via intermediate hypobromous acid (HOBr) synthesis from hydrogen peroxide and bromide, but recent findings have also suggested alternative ECM protein modifications by PXDN, including incorporation of bromide into tyrosine residues. In this work, we sought to identify the major target proteins for tyrosine bromination by HOBr or by PXDN-mediated oxidation in ECM from mouse teratocarcinoma PFHR9 cells. We detected 61 bromotyrosine (BrY)-containing peptides representing 23 proteins in HOBr-modified ECM from PFHR9 cells, among which laminins displayed the most prominent bromotyrosine incorporation. Moreover, we also found that laminin α1, laminin ß1, and tubulointerstitial nephritis antigen-like (TINAGL1) contained BrY in untreated PFHR9 cells, which depended on PXDN. We extended these analyses to lung tissues from both healthy mice and mice with experimental lung fibrosis, and in lung tissues obtained from human subjects. Analysis of ECM-enriched mouse lung tissue extracts showed that 83 ECM proteins were elevated in bleomycin-induced fibrosis, which included various collagens and laminins, and PXDN. Similarly, mRNA and protein expression of PXDN and laminin α/ß1 were enhanced in fibrotic mouse lung tissues, and also in mouse bone-marrow-derived macrophages or human fibroblasts stimulated with transforming growth factor ß1, a profibrotic growth factor. We identified 11 BrY-containing ECM proteins, including collagen IV α2, collagen VI α1, TINAGL1, and various laminins, in both healthy and mouse fibrotic lung tissues, although the relative extent of tyrosine bromination of laminins was not significantly increased during fibrosis. Finally, we also identified 7 BrY-containing ECM proteins in human lung tissues, again including collagen IV α2, collagen VI α1, and TINAGL1. Altogether, this work demonstrates the presence of several bromotyrosine-modified ECM proteins, likely involving PXDN, even in normal lung tissues, suggesting a potential biological function for these modifications.

Coupling and regulation mechanisms of the flavin-dependent halogenase PyrH observed by infrared difference spectroscopy.

Flavin-dependent halogenases are central enzymes in the production of halogenated secondary metabolites in various organisms and they constitute highly promising biocatalysts for regioselective halogenation. The mechanism of these monooxygenases includes formation of hypohalous acid from a reaction of fully reduced flavin with oxygen and halide. The hypohalous acid then diffuses via a tunnel to the substrate-binding site for halogenation of tryptophan and other substrates. Oxidized flavin needs to be reduced for regeneration of the enzyme, which can be performed in vitro by a photoreduction with blue light. Here, we employed this photoreduction to study characteristic structural changes associated with the transition from oxidized to fully reduced flavin in PyrH from Streptomyces rugosporus as a model for tryptophan-5-halogenases. The effect of the presence of bromide and chloride or the absence of any halides on the UV-vis spectrum of the enzyme demonstrated a halide-dependent structure of the flavin-binding pocket. Light-induced FTIR difference spectroscopy was applied and the signals assigned by selective isotope labeling of the protein moiety. The identified structural changes in α-helix and ß-sheet elements were strongly dependent on the presence of bromide, chloride, the substrate tryptophan, and the product 5-chloro-tryptophan, respectively. We identified a clear allosteric coupling in solution at ambient conditions between cofactor-binding site and substrate-binding site that is active in both directions, despite their separation by a tunnel. We suggest that this coupling constitutes a fine-tuned mechanism for the promotion of the enzymatic reaction of flavin-dependent halogenases in dependence of halide and substrate availability.

Identification of Down-Expressed CRNN Associated with Cancer Progression and Poor Prognosis in Laryngeal Squamous Cell Carcinoma.

BACKGROUND: The prevalence of laryngeal squamous cell carcinoma (LSCC) is increasing, and it poses a significant threat to human health; therefore, identifying specific targets for LSCC remains crucial. METHODS: Bioinformatics analysis was used to compare the different expression genes expressed in LSCC. Immunohistochemical assay and western blotting were used to analysis protein expression. Cell viability was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide)((4,5 Dimethyl thiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide)4,5 Dimethyl thiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide (MTT) and 5-ethynyl 2'-deoxyuridine (Edu) assay. Flow cytometry was used to measure the cell cycle. Cell migration was measured by wound healing assay and transwell assay. RESULTS: Our analysis revealed 36 upregulated and 65 downregulated differentially expressed genes (DEGs) when comparing LSCC tumors to adjacent tissues, with cornulin (CRNN) identified as a key hub gene connecting these DEGs. We observed a consistent downregulation of CRNN expression in LSCC cell lines and tissues and was associated with poor patient survival and the tumor microenvironment. CRNN overexpression was found to significantly inhibit cell growth, cell cycle progression, migration and invasion, while CRNN knockdown had the opposite effects. Additionally, in vivo experiments demonstrated that CRNN overexpression suppressed tumor growth in nude mice. CONCLUSIONS: CRNN functions as a potential tumor suppressor and regulates important aspects of LSCC, providing valuable insights into the role of CRNN in LSCC pathogenesis and potential for targeted therapeutic interventions.

Methylation of Phenyl Rings in Ester-Stabilized Phosphorus Ylides Vastly Enhances Their Protonophoric Activity.

We have recently discovered that ester-stabilized phosphorus ylides, resulting from deprotonation of a phosphonium salt such as [Ph3PCH2COOR], can transfer protons across artificial and biological membranes. To create more effective cationic protonophores, we synthesized similar phosphonium salts with one ((heptyloxycarbonylmethyl)(p-tolyl)bromide) or two ((butyloxycarbonylmethyl)(3,5-xylyl)osphonium bromide) methyl substituents in the phenyl groups. The methylation enormously augmented both protonophoric activity of the ylides on planar bilayer lipid membrane (BLM) and uncoupling of mammalian mitochondria, which correlated with strongly accelerated flip-flop of their cationic precursors across the BLM.

Efficacy of ceramidase inhibition on human renal cell carcinoma: a cell culture study.

OBJECTIVE: Cancer-preventative medicines like curcumin, resveratrol, and nonsteroidal anti-inflammatory medications all have their effects modulated by ceramide. According to research, these medications raise ceramide levels in cancer cells, leading to programmed cell death. Recently, cancer research has been involved in sphingolipid metabolism. The critical molecule here is ceramide. We aimed to investigate if the inhibition of ceramidases induces death in the human renal cell carcinoma cell line. MATERIALS AND METHODS: Human kidney carcinoma A-498 (ATCC® HTB-44™) cells were used as test cells. Ceranib-2, fetal bovine serum (FBS), penicillin/streptomycin, dimethyl sulfoxide, 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl-2H-tetrazolium bromide and Dulbecco's Modified Eagle Medium High Glucose, caspase 3/7, annexin-V, Bcl-2 activation dual detection, and MitoPotential kits were used. 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl-2H-tetrazolium bromide (MTT) colorimetric assay, annexin-V analysis, caspase 3/7 analysis, Bcl-2 activation analysis, and measurement of mitochondrial membrane potential were performed. RESULTS: MTT colorimetric assay results for 24 hours indicated that the viability of human renal cell carcinoma cells decreased compared to the control group with an increase in the applied concentration of the ceramidase inhibitor-ceranib-2. The growth inhibition by ceranib-2 for 24 hours did not decrease the viability under 50%; thus, it could not be possible to calculate the IC50 value for the short-term application of ceranib-2 for 24 hours to A-498 cells. A statistically significant decrease in cell viability was recorded at doses of 100, 50, 25, and 12.2 µM of ceranib-2, and no significant decrease was detected at the lower doses of ceranib-2. The highest inhibition caused by ceranib-2 on human renal cell carcinoma cells A-498 was detected at an application time of 72 hours. This inhibition was statistically significant for all applied doses of ceranib-2 on A-498 cells compared to untreated cells. Annexin-V technique that detects the translocation of phosphatidylserine to the outer membrane of apoptotic cells indicated that after the application of ceranib-2, apoptosis was triggered on A-498 cells with a total apoptotic profile of 12.12% compared to the untreated cells that were used as controls. Compared to untreated A-498 cells, a rise in percentage to 16.25% of cells with activated caspases 3/7 was recorded after applying IC50 concentration of ceranib-2 on A-498 cells for 48 hours. CONCLUSIONS: The results of our study indicated that the application of ceramidase inhibitor, ceranib-2 on human renal cell carcinoma A-498 cells cause cytotoxicity, antiproliferative, growth inhibitory, and apoptotic efficacies in a dose and time-dependent manner probably via inhibiting the acid ceramidases that hydrolyze ceramides that induce cell death. For further conclusions, more mechanical, pharmacokinetic, and pharmaceutic, as well as in vitro and in vivo anti-cancer activity investigations are required.

Bone marrow stromal cells attenuate oxygen and glucose deprivation followed by re­oxygenation­induced brain microvascular endothelial cell injury.

Ischemic stroke is a severe threat to the health of older individuals. Bone marrow mesenchymal stem cells (BMSCs) have been implicated in ischemic stroke. Urokinase­type plasminogen activator (uPA) and its specific receptor (uPAR) are associated with the pathological process of ischemic stroke. However, the relationship between BMSCs and uPA/uPAR in ischemic stroke remains unclear. For simulating the occurrence of an ischemic stroke in vitro, human cerebral microvascular endothelial cells (HBMECs) were subjected to oxygen and glucose deprivation followed by re­oxygenation (OGD/R) and were then cocultured with BMSCs. 3,4,5­dimethylthiazol­2,5­diphenyltetrazolium bromide and bromodeoxyuridine staining were used for measuring cell viability and proliferation. Flow cytometry was performed for assessing cell apoptosis. Endothelial cell tube formation was determined using angiogenesis assays. Alterations in the protein and gene expression in HBMECs were evaluated using western blot analysis and quantitative reverse transcription­polymerase chain reaction, respectively. OGD/R considerably inhibited the viability and proliferation of HBMECs by inducing apoptosis, which was reversed by BMSCs. Consistently, OGD/R­induced inhibition of angiogenesis was attenuated by BMSCs. In addition, BMSCs could protect HBMECs against OGD/R­induced injury by positively regulating the uPA/uPAR/stromal cell­derived factor­1α (SDF­1α)/C­X­C chemokine receptor type 4 (CXCR4) pathway, and uPA/uPAR could mediate the SDF­1α/CXCR4 pathway in OGD/R­treated HBMECs. Therefore, this study provides novel strategies to investigate the specific role of BMSCs in ameliorating OGD/R­induced vascular endothelial cell injury.

Circ-WDR27 regulates mycobacterial vitality and secretion of inflammatory cytokines in Mycobacterium tuberculosis-infected macrophages via the miR-370-3p/FSTL1 signal network.

Tuberculosis (TB) is a common disease caused by Mycobacterium tuberculosis (M.tb) infection. Our study was to explore the function and mechanism of circular RNA WD repeat domain 27 (circ-WDR27) in TB progression. Cell viability and apoptosis were detected by 3-(4, 5-dimethylthiazol-2-y1)-2, 5-diphenyl tetrazolium bromide assay and flow cytometry. Protein quantification was performed by Western blot. Inflammatory cytokines were examined using enzyme-linked immunosorbent assay. RNA levels were assayed via quantitative reverse-transcription polymerase chain reaction. M.tb survival was assessed using colony-forming unit assay. Target binding was analyzed via dual-luciferase reporter assay and RNA immunoprecipitation assay. Cell damages were induced by M.tb infection, and inflammatory cytokines were secreted in human macrophages. Circ-WDR27 was downregulated in TB patients and M.tb-infected macrophages. Circ-WDR27 overexpression reduced M.tb survival and released inflammatory cytokines in macrophages. Circ-WDR27 acted as a sponge for miR-370-3p. Circ-WDR27-mediated inhibition of TB progression was partly achieved by sponging miR-370-3p. miR-370-3p directly targeted Follistatin-like protein 1 (FSTL1). FSTL1 suppressed M.tb-induced cell damages, and reversed the protective role of miR-370-3p inhibition in TB progression. Circ- WDR27 regulated FSTL1 expression by targeting miR-370-3p. These results showed that circ-WDR27 repressed M.tb vitality and stimulated pro-inflammatory cytokines in M.tb-infected macrophages by affecting the miR-370-3p/FSTL1 axis.

Excessive Zinc Ion Caused PC12 Cell Death Correlating with Inhibition of NOS and Increase of RAGE in Cells.

Zinc ion (Zn2+) is an important functional factor; however, excessive Zn2+ can be toxic. To understand the neurotoxicity of excessive Zn2+ and the underlying mechanism, PC12 cells were treated with excessive Zn2+ and Zn2+ plus N, N, N', N'-Tetrakisethylenediamine (TPEN), a zinc ion chelator agent. Trypan blue and 3-(4,5-dimethyl-2- thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide, thiazolyl blue tetrazolium bromide (MTT) assays were used to test cell viability; the relative kits were used to detect the activity of NOS synthase and the content of the receptor for advanced glycation end product (RAGE) in cells. We observed that excessive zinc caused PC12 cell damage and that TPEN partially reversed cell damage caused by excessive zinc. In addition, excessive zinc decreased total nitric oxide synthase (TNOS) activity in cells, in which constitutive nitric oxide synthase (cNOS) activity was significantly reduced; however, inducible nitric oxide synthase (iNOS) activity was extremely promoted. Moreover, excessive zinc upregulated the expression of RAGE, and TPEN effectively reversed the increase in RAGE induced by excessive zinc ions. Therefore, we concluded that excessive zinc caused PC12 cell damage, correlating with the inhibition of NOS and increase of RAGE induced in cells.

LncRNA HOTAIR inhibits the progression of fibroblast-like synoviocytes by sponging miRNA-106b-5p in rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic progressive autoimmune disease of unknown etiology. Human fibroblast-like synoviocytes (HFLSs) are the main effector cells for synovial hyperplasia and invasion in RA. Long non-coding RNAs (lncRNAs) play key roles in several autoimmune diseases, including RA. We investigated the effects of lncRNA HOX transcript antisense intergenic RNA (HOTAIR) on the pathological behavior of HFLSs in RA. The microRNAs (miRNAs) with potential binding sites for lncRNA HOTAIR were predicted using Starbase v2.0. TargetScan (http://www.targetscan.org) was used to analyze the potential target genes of miR-106b-5p. The interactions were further verified using a dual-luciferase reporter assay. RNA and protein expression was determined using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blotting. The proliferation, cell invasion and migration, and cell apoptosis of HFLSs in RA was detected by the 3-(4,5-dimethylthiazol)-2,5-diphenyl-tetrazolium bromide (MTT) assay, transwell assay, and flow cytometry (FCM). The dual luciferase reporter assay confirmed the interactions between lncRNA HOTAIR and miR-106b-5p and between miR-106b-5p and SMAD family member 7 (SMAD7). The qRT-PCR results indicated that the expression of lncRNA HOTAIR was markedly decreased and that of miR-106b-5p was markedly increased in HFLSs of RA. Cell proliferation, invasion, and migration of HFLSs were inhibited by lncRNA HOTAIR upregulation, and the expression of miR-106b-5p was negatively regulated by lncRNA HOTAIR in HFLSs. Apoptosis of HFLS cells was improved by the overexpression of lncRNA HOTAIR. All the effects of lncRNA HOTAIR upregulation on HFLSs were reversed after the overexpression of miR-106b-5p. Smad7 was identified as a target gene of miR-106b-5p, and the effects of downregulation of miR-106b-5p on HFLSs could be abolished by silencing Smad7. We found that lncRNA HOTAIR was significantly downregulated in the HFLSs of patients with RA. Moreover, lncRNA HOTAIR influenced cell growth, migration, invasion, and apoptosis in HFLSs through the miR-106b-5p/Smad7 axis.

CircRNA circUSP36 impairs the stability of NEDD4L mRNA through recruiting PTBP1 to enhance ULK1-mediated autophagic granulosa cell death.

BACKGROUND: Hypercholesterolemia is defined as a high risk factor for causing female infertility by changing the cholesterol level in granulosa cells to impair the microenvironment of oocyte development and maturation. High blood levels of oxidized low-density lipoprotein (ox-LDL) undergoes an increase of autophagic granulosa cell death. Unfortunately, this underlying molecular mechanism remains largely elusive. We aim to uncover the role of circ-ubiquitin specific peptidase 36 (USP36) in autophagic granulosa cell death. METHODS: Exposure of ox-LDL on the ovarian granulosa cell-like human granulosa (KGN) cells line was established for simulating the situation of hypercholesterolemia in vitro. Levels of circUSP36 and ULK1 were detected using real-time polymerase chain reaction (RT-PCR). Cell viability and apoptosis were assessed using (4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, respectively. Immunofluorescence staining of LC3 was performed to evaluate activity of autophagy. Western blot was employed to determine expression of apoptosis and autophagy-associated markers. RNA immunoprecipitation (RIP) and RNA pull-down assays were subjected to verify the circUSP36-PTBP1-NEDD4L regulatory axis. RESULTS: Treatment of ox-LDL induced aberrantly up-regulated circUSP36. Knockdown of circUSP36 alleviated cell apoptosis and excessive autophagy of granulosa cells triggered by ox-LDL. Mechanistically, reinforced expression of circUSP36 guided and facilitated PTBP1 binding to the coding region (CDS) of NEDD4L, resulting in NEDD4L mRNA decay. ULK1 was regulated by the circUSP36-PTBP1-NEDD4L axis in granulosa cells, thereby contributing to autophagic granulosa cell death. CONCLUSIONS: In summary, ox-LDL fostered autophagic granulosa cell death through circUSP36-mediated NEDD4L mRNA decay, thus elevating ULK1 expression.

Light activation of iridium(III) complexes driving ROS production and DNA damage enhances anticancer activity in A549 cells.

The work aimed to synthesize and characterize two iridium(III) complexes [Ir(ppy)2(IPPH)](PF6) (Ir1, IPPH = (2S,3R,5S,6R)-2-(2-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)phenoxy)-6-(hydroxymethyl)tetrahydro-2H-pyran-3,4,5-triol, ppy = 2-phenylpyridine), [Ir(piq)2(IPPH)](PF6) (Ir2, piq = 1-phenylisoquinoline). The cytotoxicity of the complexes against BEL-7402, A549, HCT-116, B16 cancer cells and normal LO2 was evaluated through 3-(4,5-dimethylthiazole-2-yl)-2,5-biphenyl tetrazolium bromide (MTT) method. The complexes show no cytotoxic activity (IC50 > 100 µM) against these cancer cells, while their cytotoxicity can significantly be elevated upon illumination. The IC50 values range from 0.2 ± 0.05 to 35.5 ± 3.5 µM. The cellular uptake, endoplasmic reticulum and mitochondria localization, reactive oxygen species, the change of mitochondrial membrane potential, γ-H2AX levels, cycle arrest, apoptosis and the expression of B-cell lymphoma-2 were investigated. The calreticulin (CRT), heat shock protein 70 (HSP70), high mobility group box 1 (HMGB1) were explored. This study demonstrates that photoactivatable complexes induce cell death in A549 through ROS-mediated endoplasmic reticulum stress-mitochondrial pathway, DNA damage pathways, immunogenic cell death (ICD), activation of PI3K/AKT signaling pathway and inhibit the cell growth at S phase.

Knockdown of circ_0025908 inhibits proliferation, migration, invasion, and inflammation while stimulates apoptosis in fibroblast-like synoviocytes by regulating miR-650-dependent SCUBE2.

BACKGROUND: Circular RNAs (circRNAs) are demonstrated to play vital roles in human diseases, including rheumatoid arthritis (RA). Therefore, this research aimed to explore the effects of hsa_circRNA_0025908 (circ_0025908) on RA. METHODS: RNA expression of circ_0025908, microRNA-650 (miR-650), and Signal peptide-CUBepidermal growth factor-like containing protein 2 (SCUBE2) were assessed by real-time quantitative polymerase chain reaction; protein expression of SCUBE2, apoptosis- and invasion-related proteins was evaluated by western blot assay. Functional assays were performed using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-2H-tetrazol-3-ium bromide, 5-ethynyl-2'-deoxyuridine, transwell, flow cytometry, and enzyme linked immunosorbent assay assays. Dual-luciferase reporter, RNA immunoprecipitation, and RNA pull-down assays confirmed the interaction relationship among circ_0025908, miR-650, and SCUBE2. RESULTS: Circ_0025908 was overexpressed in synovial tissues and fibroblast-like synoviocytes (FLS) from RA patients. Inhibition of circ_0025908 repressed proliferation, migration, invasion, inflammation, and cell cycle progression, while induced apoptosis in the FLS isolated from RA patients (FLS-RA), accompanied with increased Bax, cleaved caspase-3 and E-cadherin, but declined Bcl-2, N-cadherin and Vimentin. MiR-650 was a target of circ_0025908, and SCUBE2 was a target for miR-650. Silencing of miR-650 could overturned above effects of circ_0025908 knockdown in FLS-RA, whereas its overexpression could mimic those effects by downregulating SCUBE2. Additionally, SCUBE2 expression could be positively regulated by circ_0025908 and inversely regulated by miR-650. Notably, Pearson's correlation analysis confirmed the linear correlation among circ_0025908, miR-650 and SCUBE2 in these RA tissues. CONCLUSION: Circ_0025908 inhibition can suppress FLS-RA dysfunctions through targeting miR-650/SCUBE2 axis, suggesting a new potential therapeutic clue for RA patients.

Induction of apoptosis in SGC-7901 cells by iridium(III) complexes via endoplasmic reticulum stress-mitochondrial dysfunction pathway.

This study was intended to evaluate the anticancer activity of three newly synthesized iridium(III) complexes [Ir(ppy)2(PEIP)](PF6) (1) (ppy = 2-phenylpyridine, PEIP = 2-phenethyl-1H-imidazo[4,5-f][1,10]phenanthroline), [Ir(ppy)2(SIP)](PF6) (2) (SIP = (E)-2-styryl-1H-imidazo[4,5-f][1,10]phenanthroline) and [Ir(ppy)2(PEYIP)](PF6) (3) (PEYIP = 2-phenethynyl-1H-imidazo[4,5-f][1,10]phenanthroline). The cytotoxic activity in vitro against A549, SGC-7901, HepG2, HeLa and normal NIH3T3 cells was investigated by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) method. We found that the complexes 1, 2 and 3 significantly inhibited cell proliferation, in particular, complexes 2 and 3 show high cytotoxic effect on SGC-7901 cells with an IC50 value of 5.8 ± 0.7 and 4.4 ± 0.1 µM. Moreover, cell cycle assay revealed that the complexes could block G2/M phase of the cell cycle. Apoptotic evaluation by Annexin V/PI staining indicated that complexes 1-3 can induce apoptosis in SGC-7901 cells. In addition, microscopy detection suggested that disruption of mitochondrial functions, characterized by increased generation of intracellular ROS and Ca2+ as well as decrease of mitochondrial membrane potential. Western blot analysis shows that the complexes upregulate the expression of pro-apoptotic Bax and downregulate the expression of anti-apoptotic Bcl-2, which further activates caspase-3 and prompts the cleavage of PARP. Taken together, these results demonstrated that complexes 1-3 exert a potent anticancer effect on SGC-7901 cells via ROS-mediated endoplasmic reticulum stress-mitochondrial apoptotic pathway and have a potential to be developed as novel chemotherapeutic agents for human gastric cancer. Three new iridium(III) complexes [Ir(ppy)2(PEIP)](PF6) (1) (ppy = 2-phenylpyridine, PEIP = 2-phenethyl-1H-imidazo[4,5-f][1,10]phenanthroline), [Ir(ppy)2(SIP)](PF6) (2) (SIP = 2-styryl-1H-imidazo[4,5-f][1,10]phenanthroline) and [Ir(ppy)2(PEYIP)](PF6) (3) (PEYIP = 2-phenethynyl-1H-imidazo[4,5-f][1,10]phenanthroline) were synthesized and characterized. The anticancer activity in vitro was investigated by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) method. The results show that the complexes induce apoptosis via ROS-mediated endoplasmic reticulum stress-mitochondrial dysfunction pathway.

Circ_0062558 promotes growth, migration, and glutamine metabolism in triple-negative breast cancer by targeting the miR-876-3p/SLC1A5 axis.

BACKGROUND: Circular RNAs (circRNAs) have been reported to function as vital regulators in cancers, including triple-negative breast cancer (TNBC). This study aimed to explore the role of circ_0062558 in TNBC. METHODS: The real-time quantitative polymerase chain reaction (RT-qPCR) was conducted to quantify the expressions of circ_0062558, microRNA-876-3p (miR-876-3p), and solute carrier family 1 (neutral amino acid transporter), member 5 (SLC1A5) in TNBC tissues and cells. 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyl-2H-tetrazol-3-ium bromide (MTT), thymidine analog 5-ethynyl-2'-deoxyuridine (EdU), flow cytometry, wound healing, and Transwell assays were employed for cell phenotype analyses. Protein expression was tested by western blot analysis. Dual-luciferase reporter was used to confirm the association among circ_0062558, miR-876-3p, and SLC1A5 in TNBC. Xenograft experiments were performed to elucidate the function of circ_0062558 in vivo. RESULTS: TNBC tissues and cells showed the higher level of circ_0062558 when compared with control samples. Downregulation of circ_0062558 inhibited proliferation, migration, invasion, and glutamine metabolism, while enhanced apoptosis of TNBC cells, and silencing of circ_0062558 also inhibited the growth of tumor in vivo. MiR-876-3p was confirmed as a target of circ_0062558, and circ_0062558 knockdown repressed TNBC cell malignant behaviors by increasing miR-876-3p. Furthermore, miR-876-3p inhibited malignant behaviors of TNBC cells by down-regulating SLC1A5, a newly identified target of miR-876-3p. CONCLUSION: Circ_0062558 promoted TNBC progression by enhancing proliferation, survival, migration, invasion, and glutamine metabolism via miR-876-3p/SLC1A5 axis, which was helpful for understanding the carcinogenic roles of circ_0062558.

LncRNA AFAP1-AS1 Knockdown Represses Cell Proliferation, Migration, and Induced Apoptosis in Breast Cancer by Downregulating SEPT2 Via Sponging miR-497-5p.

Background: Long non-coding RNA actin filament-associated protein1-antisense RNA 1 (AFAP1-AS1) was confirmed to be associated with tumorigenesis. However, the role of AFAP1-AS1 in breast cancer was little known. Materials and Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the levels of AFAP1-AS1, microRNA-497-5p (miR-497-5p), and Septin 2 (SEPT2) in breast cancer tissues and cells. The cell proliferation, migration, and apoptosis were tested by Methylthiazolyldiphenyl-tetrazolium bromide (MTT), Transwell and Flow cytometry assays, respectively. The targeting relationship between genes was predicted by StarBase v.3.0 and confirmed by dual-luciferase reporter assay. Pearson's correlation coefficient was applied to examine the correlation between the two groups. SEPT2 protein expression was evaluated by Western blot. Xenograft models were established to investigate the role of AFAP1-AS1 knockdown in vivo. Results: AFAP1-AS1 was upregulated in breast cancer tissues and cells, and AFAP1-AS1 knockdown could hinder proliferation and migration of breast cancer cells, and contribute to cell apoptosis. MiR-497-5p, which was downregulated in breast cancer, was verified to be a target of AFAP1-AS1 and inversely correlated with AFAP1-AS1 expression. SEPT2, as a target gene of miR-497-5p, was negatively regulated by miR-497-5p and positively correlated with AFAP1-AS1 expression. Importantly, AFAP1-AS1 could upregulate SEPT2 expression by sponging miR-497-5p, and modulate cell progression by regulation of the miR-497-5p/SEPT2 axis in breast cancer. Conclusion: AFAP1-AS1 knockdown repressed the progression of breast cancer cells by sponging miR-497-5p and downregulating SEPT2.

lncRNA DANCR Promotes Proliferation and Metastasis of Breast Cancer Cells Through Sponging miR-4319 and Upregulating VAPB.

Background: Breast cancer is one of the most prevalent cancers that often occur in females. Long noncoding RNA differentiation antagonizing nonprotein coding RNA (DANCR) has been involved in the pathogenesis of various tumors, including breast cancer. This study aimed to investigate the role and underlying mechanism of DANCR in breast cancer. Materials and Methods: The level of DANCR was detected in breast cancer tissues and cells by quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability was evaluated by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. Cell apoptosis was assessed using flow cytometry. Cell migration and invasion were estimated by the Transwell assay. The relationship between DANCR, miR-4319, and vesicle-associated membrane protein-associated protein B (VAPB) was confirmed by bioinformatic analysis and dual-luciferase reporter assay. The level of microRNA-4319 (miR-4319) was tested by qRT-PCR. The expression of VAPB was measured by qRT-PCR or Western blot assay. Results: DANCR and VAPB were upregulated, while miR-4319 was downregulated in breast cancer tissues and cells. Knockdown of DANCR hindered proliferation, migration, and invasion and promoted apoptosis of breast cancer cells. DANCR knockdown inhibited breast cancer development through regulating miR-4319. Inhibition of miR-4319 restrained breast cancer cell progression by targeting VAPB. Moreover, DANCR regulated VAPB expression by sponging miR-4319 in breast cancer cells. Conclusion: DANCR facilitated breast cancer cell progression through regulating the miR-4319/VAPB axis, indicating that DANCR might be a potential biomarker and therapeutic target for breast cancer treatment.

Hunting the eagle killer: A cyanobacterial neurotoxin causes vacuolar myelinopathy.

Vacuolar myelinopathy is a fatal neurological disease that was initially discovered during a mysterious mass mortality of bald eagles in Arkansas in the United States. The cause of this wildlife disease has eluded scientists for decades while its occurrence has continued to spread throughout freshwater reservoirs in the southeastern United States. Recent studies have demonstrated that vacuolar myelinopathy is induced by consumption of the epiphytic cyanobacterial species Aetokthonos hydrillicola growing on aquatic vegetation, primarily the invasive Hydrilla verticillata Here, we describe the identification, biosynthetic gene cluster, and biological activity of aetokthonotoxin, a pentabrominated biindole alkaloid that is produced by the cyanobacterium A. hydrillicola We identify this cyanobacterial neurotoxin as the causal agent of vacuolar myelinopathy and discuss environmental factors-especially bromide availability-that promote toxin production.

Protective effects and potential mechanisms of (2-Carboxyethyl) dimethylsulfonium Bromide (Br-DMPT) on gill health status of on-growing grass carp (Ctenopharyngodon idella) after infection with Flavobacterium columnare.

In this study, the protective effects and potential mechanisms of (2-Carboxyethyl) dimethylsulfonium Bromide (Br-DMPT) were evaluated in relation to the gill health status of on-growing young grass carp (Ctenopharyngodon idella). A total of 450 grass carp (216.49 ± 0.29 g) were randomly distributed into five treatments of three replicates each (30 fish per replicate) and were fed diets supplemented with gradational Br-DMPT (0-520.0 mg/kg levels) for 60 days. Subsequently, the fish were challenged with Flavobacterium columnare for 3 days, and the gills were sampled to evaluate antioxidant status and immune responses evaluation. Our results showed that, when compared to the control group, dietary supplementation with appropriate Br-DMPT levels resulted in the following: (1) decreased gill rot morbidity and improved gill histological symptoms after exposure to F. columnare (P < 0.05); (2) improved activities and gene expression levels (except GSTP2 gene) of antioxidant enzymes and decreased oxidative damage parameter values (reactive oxygen species, malondialdehyde and protein carbonyl) (P < 0.05), which may be partially associated with the nuclear factor-erythroid 2-related factor 2 (Nrf2) signalling pathway (P < 0.05); (3) increased lysozyme (LZ) and acid phosphatase (ACP) activities and complement 3 (C3), C4 and immunoglobulin M (IgM) contents, and upregulated genes expressions of antibacterial peptides (liver-expressed antimicrobial peptide-2A, -2B, hepcidin, ß-defensin and mucin2) (P < 0.05); (4) upregulated gene expressions of anti-inflammatory cytokines (except IL--4/13B) that may be partially to the TOR/(S6K1, 4E-BP1) signalling pathway, and downregulated gene expressions of pro-inflammatory cytokines (except IL-12P35) may be partially to the IKK ß, γ/IκBα/NF-kB) signalling pathway (P < 0.05). Taken together, our results indicate that dietary supplementation with appropriate amounts of Br-DMPT may effectively protect on-growing grass carp from F. columnare by strengthening gill antioxidant capacity and immunity. Furthermore, based on measures of combatting gill rot, antioxidant indices (MDA) and immune indices (LZ), the dietary Br-DMPT supplementation levels for on-growing grass carp are recommended to be 291.14, 303.38 and 312.01 mg/kg diet, respectively.

Bromide impairs the circadian clock and glycolytic homeostasis via disruption of autophagy in rat H9C2 cardiomyocytes.

BACKGROUND: Trace elements function as essential cofactors that are involved in various biochemical processes in mammals. Autophagy is vital for nutrient supplement, which is an important Zeitegber for the circadian homeostasis in heart. Here, we considered the possibility that autophagy, as well as the cardiomyocyte clock and glycolysis are interlinked. Detrimental effects were observed when cardiac system is exposed to bromine containing drugs. This study investigated the effects and mechanisms of bromide on the circadian clock and glycolytic metabolism of H9C2 cardiomyocytes. RESULTS: In the present study, bromide does not affect cell viability and apoptosis of H9C2 cardiomyocytes. Bromide dampens the clock and glycolytic (Hk2 and Pkm2) gene expression rhythmicity in a dose-dependent manner. Additionally, bromide inhibits autophagic process in H9C2 cardiomyocytes. In contrast, rapamycin (an autophagy inducer) dramatically restores the inhibitory effect of NaBr on the mRNA expression levels of clock genes (Bmal1, Cry1 and Rorα) and glycolytic genes (Hk2 and Pkm2). CONCLUSIONS: Our results reveal that bromide represses the clock and glycolytic gene expression patterns, partially through inhibition of autophagy.

Impact of Self-Assembled Monolayer Design and Electrochemical Factors on Impedance-Based Biosensing.

Real-time sensing of proteins, especially in wearable devices, remains a substantial challenge due to the need to convert a binding event into a measurable signal that is compatible with the chosen analytical instrumentation. Impedance spectroscopy enables real-time detection via either measuring electrostatic interactions or electron transfer reactions while simultaneously being amenable to miniaturization for integration into wearable form-factors. To create a more robust methodology for optimizing impedance-based sensors, additional fundamental studies exploring components influencing the design and implementation of these sensors are needed. This investigation addresses a sub-set of these issues by combining optical and electrochemical characterization to validate impedance-based sensor performance as a function of (1) biorecognition element density, (2) self-assembled monolayer chain length, (3) self-assembled monolayer charge density, (4) the electrochemical sensing mechanism and (5) the redox reporter selection. Using a pre-existing lysozyme aptamer and lysozyme analyte combination, we demonstrate a number of design criteria to advance the state-of-the-art in protein sensing. For this model system we demonstrated the following: First, denser self-assembled monolayers yielded substantially improved sensing results. Second, self-assembled monolayer composition, including both thickness and charge density, changed the observed peak position and peak current. Third, single frequency measurements, while less informative, can be optimized to replace multi-frequency measurements and in some cases (such as that with zwitterionic self-assembled monolayers) are preferred. Finally, various redox reporters traditionally not used in impedance sensing should be further explored. Collectively, these results can help limit bottlenecks associated with device development, enabling realization of next-generation impedance-based biosensing with customize sensor design for the specific application.