Near-IR/Visible-Emitting Thiophenyl-Based Ru(II) Complexes: Efficient Photodynamic Therapy, Cellular Uptake, and DNA Binding.

Near-IR-emitting and/or efficiently photodynamic water-soluble Ru(II) complexes that hold great application potentials as photodynamic therapy and/or photodetection agents for cancers have been poorly explored. In this paper, the solvatochromism, calf thymus DNA binding, and singlet oxygen generation properties of a known ruthenium(II) complex of visible-emitting [Ru(bpy)2(dtdpq)](ClO4)2 (Ru1) and a new homoleptic complex of near-IR-emitting [Ru(dtdpq)3](ClO4)2 (Ru2) (bpy = 2,2'-bipyridine, dtdpq = 2,3-bis(thiophen-2-yl)pyrazino[2,3-f][1,10]phenanothroline) in water are reported. Moreover, DNA photocleavage, singlet oxygen generation in HeLa cells, cellular uptake/localization, and in vitro photodynamic therapy for cancer cells of water-soluble Ru1 are described in detail. The results show that Ru1 acted as potent photodynamic cancer therapy and mitochondrial imaging agents. Ru2 exhibited very strong solvatochromism from a visible emission maximum at 588 nm in CH2Cl2 to the near-IR region at 700 nm in water and singlet oxygen generation yield in water (23%) and DNA binding properties (intercalative DNA binding constant on the order of 106 M-1) comparable to those of Ru1, which should make Ru2 attractive for the aforementioned applications of Ru1 if the water solubility of Ru2 can be improved enough for the studies above.

TEM8 functions as a receptor for uPA and mediates uPA-stimulated EGFR phosphorylation.

BACKGROUND: TEM8 is a cell membrane protein predominantly expressed in tumor endothelium, which serves as a receptor for the protective antigen (PA) of anthrax toxin. However, the physiological ligands for TEM8 remain unknown. RESULTS: Here we identified uPA as an interacting partner of TEM8. Binding of uPA stimulated the phosphorylation of TEM8 and augmented phosphorylation of EGFR and ERK1/2. Finally, TEM8-Fc, a recombinant fusion protein comprising the extracellular domain of human TEM8 linked to the Fc portion of human IgG1, efficiently abrogated the interaction between uPA and TEM8, blocked uPA-induced migration of HepG2 cells in vitro and inhibited the growth and metastasis of human MCF-7 xenografts in vivo. uPA, TEM8 and EGFR overexpression and ERK1/2 phosphorylation were found co-located on frozen cancer tissue sections. CONCLUSIONS: Taken together, our data provide evidence that TEM8 is a novel receptor for uPA, which may play a significant role in the regulation of tumor growth and metastasis.

Aggregation of Ribosomal Protein S6 at Nucleolus Is Cell Cycle-Controlled and Its Function in Pre-rRNA Processing Is Phosphorylation Dependent.

Ribosomal protein S6 (rpS6) has long been regarded as one of the primary r-proteins that functions in the early stage of 40S subunit assembly, but its actual role is still obscure. The correct forming of 18S rRNA is a key step in the nuclear synthesis of 40S subunit. In this study, we demonstrate that rpS6 participates in the processing of 30S pre-rRNA to 18S rRNA only when its C-terminal five serines are phosphorylated, however, the process of entering the nucleus and then targeting the nucleolus does not dependent its phosphorylation. Remarkably, we also find that the aggregation of rpS6 at the nucleolus correlates to the phasing of cell cycle, beginning to concentrate in the nucleolus at later S phase and disaggregate at M phase. J. Cell. Biochem. 117: 1649-1657, 2016. © 2015 Wiley Periodicals, Inc.

An Electrostatically Self-Assembled Thin Film Made of Zn-Substituted Tungstoborate and Rhodamine B with Photoelectrochemical Properties.

An electrostatically self-assembled multilayer thin film consisting of alternating layers of Keggin polyoxometalate of Zn-substituted tungstoborate (BW11Zn) and Rhodamine B (RhB) has successfully been prepared on a quartz and indium-tin oxide (ITO) glass substrate. The ultraviolet-visible (UV-vis) absorption spectra demonstrated that the electrostatically self-assembled film of (BW11Zn/RhB)n was uniformly deposited layer by layer, and the RhB molecules in the film formed the J-aggregation. The photoelectrochemical investigations showed that the films generated stable cathodic photocurrents that originated from RhB, and the maximal cathodic photocurrent density generated by an eight-layer film was 4.9 µA/cm2 while the film was irradiated with 100 mW/cm2 polychromatic light of 730 nm > λ > 325 nm at an applied potential of 0 V versus a saturated calomel electrode.

Preparation, electrochemical properties and electrocatalytic activity of Zn-substituted tungstoborate modified electrode.

3-Aminopropyltrimethoxysilane (APTMS) was covalently grafted on a glassy carbon electrode (GCE) by silicon-oxygen bonds formation. The APTMS-modified GCE was used as a suitable charged substrate to fabricate Keggin Zn-substituted tungstoborate (BW11Zn)-consisting monolayer film through layer-by-layer assembly based on the electrostatic attraction. This modification strategy is proven to be a general one suitable for anchoring many kinds of POMs on the APTMS-modified GCE. The APTMS/BW11Zn film obtained on GCE is electrochemically active in acid aqueous solutions and exhibited three pairs of well defined, stable and quasi-reversible cyclic voltammetry peaks in the pH range 0-2. The anodic and cathodic peak currents are linearly proportional to the scan rate in the 200-1000 mV s(-1), indicating a surface confined electrode process. The formal potentials of BW11Zn film, E0 versus saturated calomel electrode (SCE), are -0.27, -0.43, -0.55 V in pH 1 H2SO4 solution and changed linearly with the slope of 44, 63, and 60 mV/pH in the pH range 0-2, respectively. The BW11Zn/APTMS/GC electrode shows good catalytic activity for the reduction of BrO3-, NO2- and H2O2.

Preparation and photoelectrochemical properties of a self-assembled film based on wheel type polyoxomolybdate and hemicyanine derivative.

A new electrostatically self-assembled film has been successfully prepared on quartz and indium-tin-oxide (ITO) coated glass substrates by alternating adsorption of a wheel-shaped polyoxomolybdate {Mo154} and a hemicyanine of (E)-1,1'-methylenebis(4-(4-(dimethylamino)styryl)pyridinium) bromide (H1). The UV-visible spectra demonstrated that the film was uniform, reproducible, and the H1 in the film forms the J-aggregation. Photoelectrochemical investigations showed that the films can generate stable cathodic photocurrent, and the cathodic photocurrent density of three-layer film was 5.1 microA/cm2 while irradiated with 100 mW/cm2 polychromatic light of 730 nm > lambda > 325 nm at an applied potential of -0.3 V versus saturated calomel electrode.

Topical Ozone Accelerates Diabetic Wound Healing by Promoting Re-Epithelialization through the Activation of IGF1R-EGFR Signaling.

Ozonated oil increases the healing of chronic diabetic wounds, but the underlying mechanisms remain unclear. We investigated the effect of topical ozonated oil on wound healing in mice with diabetes with diet-induced obesity and further elucidated the role of EGFR and IGF1R signaling in diabetic wound healing. We found that topical ozonated oil accelerated wound healing; increased phosphorylation of IGF1R, EGFR, and VEGFR; and improved vascularization at the wound leading edge in mice with diabetes with diet-induced obesity. Exposure of normal epidermal keratinocytes to ozonated medium (20 µM for 2 hours daily) increased cell proliferation and migration distance by increasing phosphorylation of IGF1R and EGFR and downstream phosphoinositide 3-kinase, protein kinase B, and extracellular signal-regulated kinase. These findings shed light on the mechanism for topical ozone action in chronic wounds and support its potential therapeutic application.

NMDA receptor activation induces damage of alveolar type II cells and lung fibrogenesis through ferroptosis.

Ferroptosis, a newly discovered type of regulated cell death, has been implicated in numerous human diseases. Idiopathic pulmonary fibrosis (IPF) is a progressive and ultimately fatal interstitial lung disease with poor prognosis and limited treatment options. Emerging evidence has linked ferroptosis and glutamate-determined cell fate which is considered a new light on the etiology of pulmonary fibrosis. Here, we observed that N-methyl d-aspartate receptor (NMDAR) activation promoted cell damage and iron deposition in MLE-12 cells in a dose-, time-, and receptor-dependent manner. This mediated substantial Ca2+ influx, upregulated the expression levels of nNOS and IRP1, and affected intracellular iron homeostasis by regulating the expression of iron transport-related proteins (i.e., TFR1, DMT1, and FPN). Excessive iron load promoted the continuous accumulation of total intracellular and mitochondrial reactive oxygen species, which ultimately led to ferroptosis. NMDAR inhibition reduced lung injury and pulmonary fibrosis in bleomycin-induced mice. Bleomycin stimulation upregulated the expression of NMDAR1, nNOS, and IRP1 in mouse lung tissues, which ultimately led to iron deposition via regulation of the expression of various iron metabolism-related genes. NMDAR activation initiated the pulmonary fibrosis process by inducing iron deposition in lung tissues and ferroptosis of alveolar type II cells. Our data suggest that NMDAR activation regulates the expression of iron metabolism-related genes by promoting calcium influx, increasing nNOS and IRP1 expression, and increasing iron deposition by affecting cellular iron homeostasis, ultimately leading to mitochondrial damage, mitochondrial dysfunction, and ferroptosis. NMDAR activation-induced ferroptosis of alveolar type II cells might be a key event to the initiation of pulmonary fibrosis.

Bipolar Hemicyanine-Based Photodynamic Modulation of Type I Pathway for Efficient Sterilization and Real-Time Monitoring.

The development of photosensitizers with low oxygen dependence for generating type I ROS is in high demand to be able to treat pathogenic infections in hypoxic conditions. Here, we report a series of cationic bipolar hemicyanines (C3, C6, and C10) with alkyl linkers of varying lengths that are found to exclusively produce hydroxyl radicals and superoxide radicals with the aid of white light and that have different antibacterial abilities toward a variety of pathogens. Furthermore, hemicyanines could differentiate live from dead bacteria to track the status of pathogens in real time. It is expected that hemicyanines could be applied for combatting various microbial infections in hypoxia and real-time tracking.

Preparation and photocatalytic activity of an electrostatically self-assembled film made of [PMo12O40](3-) and a bipolar hemicyanine cation.

An electrostatically self-assembled film of PMo12/H6 has successfully been prepared on quartz substrates by alternating adsorption of [PMo12O40(3-) (PMo12) and a bipolar hemicyanine derivative of (E)-1,1'-(hexane-1,6-diyl)bis(4-(4-(dimethylamino)styryl)pyridinium) bromide (H6Br2). The UV-visible spectra showed that the film was uniformly deposited and the charge transfer between two film-forming components might occur in the film. The photocatalytic performance of the film was studied for the degradation of aqueous dye Methyl Red (MR) under UV irradiation. The degradation of MR follows Langmuir-Hinshelwood first-order kinetics.

Preparation and electrochemical and electrocatalytic properties of nanocomposite multilayer film based on a Keggin-type phosphomolybdate.

An electrostatically self-assembled multilayer film has successfully been prepared on quartz or indium-tin-oxide substrates by alternating adsorption of a Keggin-type phosphomolybdate H3PMo12O40 (PMo12) and 1,10-diaminodecane (1,10-DAD). The formation of (PMo12/1,10-DAD), film was investigated by ultraviolet (UV) spectroscopy. The UV spectra showed that the deposition of the films was uniform and reproducible. The cyclic voltammetry on the PMo12-based multilayer film indicated that the PMo12 anions in the film undergo rapid four 2e(-)/2H+ redox processes, and electrocatalytically active towards the reduction of bromate.

[Synthesis, spectroscopy and photocatalytic activity of II B elements substituted tungstoborate heteropoly complexes].

The Keggin II B element-monosubstitiuted heteropoly compounds with the stoichiometry of K7 [BW11 O39 M(H2O)] (M = Zn, Cd) were prepared by one-pot method and characterizated via elemental analyses, FTIR, UV and XRD. The photocatalytic activity of K7 [BW11O39M(H2O)] was tested vis degradation of the model molecule, methyl red (MR). After 60 min irradiation in the presence of K7 [BW11O39M(H2O)] (20 mg x L(-1)), the degradation rate of an aqueous MR (25 micromol X L(-1), pH 2) got to 95%.

Design and Application of Conjugated Polymer Nanomaterials for Detection and Inactivation of Pathogenic Microbes.

Infectious deaths due to drug resistance of pathogens caused by the abuse of antibiotics have seriously endangered public health in the world. Therefore, it is urgent to develop diversified methods for rapid detection of pathogens and antimicrobial drugs that are not prone to develop resistance. Conjugated polymers (CPs) are macromolecular compounds composed of many luminescent units through covalent bond. They have high molar extinction coefficient and strong light absorption capacity. In addition, they have good photo stability and excellent biocompatibility. In recent years, conjugated polymer nanomaterials (CPNs) have stimulated the research enthusiasm of many researchers because of the materials' small size, high fluorescence intensity, and easy modification. This article reviews the recent research progress of conjugated polymer nanomaterials in the detection and killing of pathogenic microbes.

Poly(p-phenylenevinylene) nanoparticles modified with antiEGFRvIII for specific glioblastoma therapy.

Glioblastoma is the most common primary brain cancer and it is nearly impossible to remove the entire tumor with surgery or a single drug. EGFRvIII is the most frequent genetic change associated with glioblastoma, so EGFRvIII-based targeting therapies provide promise for treating glioblastoma. Herein, poly[2-methoxy-5-(2'-ethylhexyloxy)-p-phenylenevinylene] (PPV) was used as the core to prepare a conjugated polymer nanoparticle (PPVN) modified with anti-EGFRvIII (PPVN-A) that exhibited high ROS generation ability under white light irradiation. PPVN-A could target EGFRvIII-overexpressed tumor cells and damaged more than 90% of tumor cells with the light illumination while PPVN without modification exhibited no obvious cytotoxicity toward these cells under the same condition. Thus, the photodynamic treatment of glioblastoma cells using PPVN-A could be achieved, indicating the potential of anti-EGFRvIII-modified nanoparticles as a therapeutic material for treating glioblastoma in clinic.

A triphenylamine-grafted imidazo[4,5-f][1,10]phenanthroline ruthenium(II) complex: acid-base and photoelectric properties.

A new heteroleptic ruthenium(II) complex of [Ru(Hipdpa)(Hdcbpy)(NCS)(2)](-).0.5H(+).0.5[N(C(4)H(9))(4)](+) Ru(Hipdpa) {where Hdcbpy = monodeprotonated 4,4'-dicarboxy-2,2'-bipyridine and Hipdpa = 4-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)-N,N-diphenylaniline} was synthesized and characterized by elementary analysis, standard spectroscopy techniques, and cyclic voltammetry. The ground- and excited-state acid-base properties of Ru(Hipdpa) were studied by means of UV-vis absorption spectrophotometric and spectrofluorimetric titrations in 4:1(v/v) Britton-Robinson/dimethylformamide buffer solution. The four-step separate protonation/deprotonation processes were found in the ground states, and one of which taking place near the physiological pH range. The two observable excited-state protonation/deprotonation processes were found for the Ru(Hipdpa), constituting pH-induced "off-on-off" emission switches. The performance of the complexes as photosensitizers in nanocrystalline TiO(2)-based liquid solar cells containing an electrolyte solution (0.05 M I(2), 0.5 M LiI, and 0.5 M 4-tert-butylpyridine in 50% acetonitrile and 50% propylene carbonate) was investigated and found to achieve a much improved device performance (a short-circuit photocurrent density of 18.7 mA cm(-2), an open-circuit voltage of 630 mV, and an overall conversion efficiency of 6.85%) compared to a triphenylamine-free parent complex [Ru(Hpip)(Hdcbpy)(NCS)(2)](-).[N(C(4)H(9))(4)](+)-based device {Hpip = 2-phenyl-1H-imidazo[4,5-f][1,10]phenanthroline} and a comparable performance to that of cis-bis(isothiocyanato)bis(2,2'-bipyridine-4,4'-dicarboxylic acid)ruthenium(II) (N3) under identical experimental conditions. A density functional theory calculation of the molecular structures and electronic properties of the complexes was also carried out in an effort to understand their effectiveness in TiO(2)-based solar cells.

Self-assembled films of a biferrocenyl-containing hemicyanine derivative with SiW12O40(4-): preparation, UV-visible spectroscopy and electrochemical properties.

Electrostatic self-assembled films were successfully prepared by alternating deposition of SiW12O40(4-) and a biferrocenyl-containing hemicyanine derivative on quartz or indium-tin-oxide coated glass substrates. The films were characterized by UV-visible absorption spectroscopy and cyclic voltammetry.

Recent Progress in Polynuclear Ruthenium Complex-Based DNA Binders/Structural Probes and Anticancer Agents.

Ruthenium complexes have stood out by several mononuclear complexes which have entered into clinical trials, such as imidazolium [trans-RuCl4(1H-imidazole)(DMSO-S)] (NAMI-A) and ([Ru(II)(4,4'-dimethyl-2,2'-bipyridine)2-(2(2'-,2'':5'',2'''-terthiophene)-imidazo[4,5-f] [1,10]phenanthroline)] 2+) (TLD-1433), opening a new avenue for developing promising ruthenium-based anticancer drugs alternative to Cisplatin. Polynuclear ruthenium complexes were reported to exhibit synergistic and/or complementary effects: the enhanced DNA structural recognition and DNA binding as well as in vitro anticancer activities. This review overviews some representative polynuclear ruthenium complexes acting as DNA structural probes, DNA binders and in vitro anticancer agents, which were developed during last decades. These complexes are reviewed according to two main categories of homo-polynuclear and hetero-polynuclear complexes, each of which is further clarified into the metal centers linked by rigid and flexible bridging ligands. The perspective, challenges and future efforts for investigations into these exciting complexes are pointed out or suggested.

DNA groove-binding and acid-base properties of a Ru(II) complex containing anthryl moieties.

DNA groove binders have been poorly studied as compared to the intercalators. A novel Ru(II) complex of [Ru(aeip)2(Haip)](PF6)2 {Haip = 2-(9-anthryl)-1H-imidazo[4,5-f][1,10]phenanthroline and aeip = 2-(anthracen-9-yl)-1-ethyl-imidazo[4,5-f][1, 10]phenanthroline} is synthesized and characterized by elemental analysis, 1H NMR spectroscopy and mass spectrometry. The complex is evidenced to be a calf-thymus DNA groove binder with a large intrinsic binding constant of 106 M-1 order of magnitude as supported by UV-visible absorption spectral titrations, salt effects, DNA competitive binding with ethidium bromide, DNA melting experiment, DNA viscosity measurements and density functional theory calculations. The acid-base properties of the complex studied by UV-Vis spectrophotometric titrations are reported as well.

Conjugated Polymer and Triphenylamine Derivative Codoped Nanoparticles for Photothermal and Photodynamic Antimicrobial Therapy.

The photothermal conjugated polymer (DPPT-TT) and a triphenylamine derivative (DPATP-CN) codoped nanoparticles (DDNPs) were designed and prepared via self-assembly. The obtained DDNPs exhibit both efficient and stable photothermal properties and excellent ROS production capability to synergistically achieve photothermal therapy (PTT) and photodynamic therapy (PDT). DDNPs showed antimicrobial activity with more than 70%, 90%, and 99% inhibition ratio, respectively, toward Gram-(-) bacteria (E. coli), Gram-(+) bacteria (S. aureus), and fungi (C. albicans) under combined irradiation of near-infrared light and white light. Therefore, DDNPs are broad-spectrum antimicrobial materials and provide a significant perspective to select an appropriate sterilization strategy for different microorganisms.

pH-Sensitive Near-IR Emitting Dinuclear Ruthenium Complex for Recognition, Two-Photon Luminescent Imaging, and Subcellular Localization of Cancer Cells.

A dinuclear Ru(II) complex of [(bpy)2Ru(Hdip)Ru(H2bip)](ClO4)4 {bpy is 2,2'-bipyridine, Hdip is 2-(2,6-di(pyridin-2-yl)-pyridin-4-yl)-1H-imidazo[4,5-f]-[1,10]phenanthroline, and H2bip is 2,6-bis(imidazole-2-yl)-pyridine} was synthesized and characterized by elemental analysis, mass spectrometry, and 1H NMR spectroscopy. Spectrophotometric pH titrations in aqueous buffer and in vitro cell experiments indicated the response ability of the complex to pH fluctuations in the physiological pH range (6.0-8.0). The complex was found to be capable of differentiating live HeLa cells from healthy HEK293 cells by selectively accumulating in lysosomes of the HeLa cells. The low cytotoxicity (IC50 > 100 µM), a large Stokes shift (∼200 nm), strong near-IR emission at ∼700 nm, a relatively long excited state lifetime, high photostability, and solubility make this complex considerably promising in real-time tracking and visualization of lysosomes in live cells. More interestingly, the tumor cell-specific two-photon luminescent imaging properties also endow this Ru complex with potential for applications in high-resolution tumor imaging and luminescence-guided tumor resection.