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Here, we describe the design of a molecular probe (NB-ALA) based on the Nile Blue fluorophore, which can detect alanine aminopeptidase enzyme (a kidney damage biomarker) in urine by simple fluorometric measurements.

Cellular senescence is a stable cell cycle arrest in response to stress or other damage stimuli to maintain tissue homeostasis. However, the accumulation of senescent cells can lead to the progression of various senescence-related disorders. In this paper, we describe the development of a β-galactosidase-activatable near-infrared (NIR) senoprobe

[EN] beta-Galactosidase (beta-Gal) is a widely used enzyme as a reporter gene in the field of molecular biology which hydrolyzes the beta-galactosides into monosaccharides. beta-Gal is an essential enzyme in humans and its deficiency or its overexpression results in several rare diseases. Cellular senescence is probably one of the most relevant physiological disorders that involve beta-Gal enzyme. In this review, we assess the progress made to date in the design of molecular-based probes for the detection of beta-Gal both in vitro and in vivo. Most of the reported molecular probes for the detection of beta-Gal consist of a galactopyranoside residue attached to a signalling unit through glycosidic bonds. The beta-Gal-induced hydrolysis of the glycosidic bonds released the signalling unit with remarkable changes in color and/or emission. Additional examples based on other approaches are also described. The wide applicability of these probes for the rapid and in situ detection of de-regulation beta-Gal-related diseases has boosted the research in this fertile field, R.M laboratory members received the financial support from the Spanish Government (project RTI2018-100910-B-C41) and the Generalitat Valenciana (project PROMETEO 2018/024). B.L-T. received support from the Spanish Ministry of Economy for their PhD grants (FPU15/02707). J. F.-B received fellowship (CD19/00038)

[EN] The characteristics and electromechanical properties of conductive polymers together to their biocompatibility have boosted their application as a suitable tool in regenerative medicine and tissue engineering. However, conducting polymers as drug release materials are far from being ideal. A possibility to overcome this drawback is to combine conducting polymers with on-command delivery particles with inherent high-loading capacity. In this scenario, we report here the preparation of conduction polymers containing gated mesoporous silica nanoparticles (MSN) loaded with a cargo that is delivered on command by electro-chemical stimuli increasing the potential use of conducting polymers as controlled delivery systems. MSNs are loaded with Rhodamine B (Rh B), anchored to the conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) doped with poly[(4-styrenesulfonic acid)-co-(maleic acid)], functionalized with a bipyridinium derivative and pores are capped with heparin (P3) by electrostatic interactions. P3 releases the entrapped cargo after the application of ¿640 mV voltage versus the saturated calomel electrode (SCE). Pore opening in the nanoparticles and dye delivery is ascribed to both (i) the reduction of the grafted bipyridinium derivative and (ii) the polarization of the conducting polymer electrode to negative potentials that induce detachment of positively charged heparin from the surface of the nanoparticles. Biocompatibility and cargo release studies were carried out in HeLa cells cultures., Alba Garcia-Fernandez, Beatriz Lozano-Torres contributed equally to this work. A. Garcia-Fernandez and B. Lozano-Torres are grateful to the "Ministerio de Economia y Competitividad" of the Spanish Government for her PhD fellowships. J. F. Blandez thanks the "Universitat Politecnica de Valencia" for his postdoctoral fellowship (PAID-10-17). The authors thank to the Spanish Government (Projects RTI2018-100910-B-C41 and RTI2018-101599-B-C22 (MCUI/AEI/FEDER, EU)) and the Generalitat Valencia (Project PROMETEO2018-024) for support.

[EN] A new method for senescent cell detection is described, which is based on lipofuscin labeling with a fluorescent reporter through a biorthogonal strain-promoted azide-alkyne cycloaddition. The sensing protocol involves a first step where the interaction of lipofuscin with a Sudan Black B derivative containing an azide moiety (SBB-N3 ) is carried out. In the final step, the azide moiety reacts with a fluorophore containing a cyclooctene ring (BODIPY). The efficacy of this two-step protocol is assessed in senescent melanoma SK-MEL-103 cells, senescent triple-negative breast cancer MDA-MB-231 cells and senescent WI-38 fibroblasts. In all cases, a clear fluorescence pattern was observed in senescent cells, compared to proliferative cells, only when the SBB-N3 -BODIPY probe was formed. Our results provide an alternative tool for the detection of senescent cells, based on an in situ bio-orthogonal reaction for lipofuscin labeling, RM laboratory members are grateful for financial support from the FEDER foundation of European Union (IDIFEDER/2021/044), the Spanish Government (projects RTI2018-100910-B-C41 and RTI2018-101599-B-C22) and the Generalitat Valenciana (project PROMETEO 2018/024). BL-T and AG-F acknowledge their current Margarita Salas postdoctoral fellowship from UPV-MIU and 'Next Generation EU' program. JF-B is grateful for his Sara Borrell postdoctoral fellowship (CD19/00038).

Triple-negative breast cancer (TNBC) is a very aggressive subtype of breast cancer with a poor prognosis and limited effective therapeutic options. Induction of senescence, arrest of cell proliferation, has been explored as an effective method to limit tumor progression in metastatic breast cancer. However, relapses occur in some patients, possibly as a result of the accumulation of senescent tumor cells in the body after treatment, which promote metastasis. In this study, we explored the combination of senescence induction and the subsequent removal of senescent cells (senolysis) as an alternative approach to improve outcomes in TNBC patients. We demonstrate that a combination treatment, using the senescence-inducer palbociclib and the senolytic agent navitoclax, delays tumor growth and reduces metastases in a mouse xenograft model of aggressive human TNBC (hTNBC). Furthermore, considering the off-target effects and toxicity derived from the use of navitoclax, we propose a strategy aimed at minimizing the associated side effects. We use a galacto-conjugated navitoclax (nav-Gal) as a senolytic prodrug that can preferentially be activated by β-galactosidase overexpressed in senescent cells. Concomitant treatment with palbociclib and nav-Gal in vivo results in the eradication of senescent hTNBC cells with consequent reduction of tumor growth, while reducing the cytotoxicity of navitoclax. Taken together, our results support the efficacy of combination therapy of senescence-induction with senolysis for hTNBC, as well as the development of a targeted approach as an effective and safer therapeutic opportunity.

There is a growing need for non-invasive, cheap, and versatile diagnostic methods and the development of low-cost point-of-care assays constitutes a potential solution. Here, we describe the design of a renal clearable fluorogenic probe (Cy7Gal) which produces a fluorogenic signal readable in the urine. The Cy7Gal probe is applied to the detection of the burden of senescence in several in vivo models. The probe is composed of a dye (Cy7) conjugated with a galactose derivative. Upon administration of the probe in vivo, the up-regulated β-galactosidase enzyme in senescent cells cleaves the O-glycosidic bond in Cy7Gal, releasing the highly emissive Cy7 dye that is renally cleared and measured in unmodified urine by an IVIS imaging system or by a fluorimeter. A good correlation between the burden of senescence and emission in urine is observed. Cy7Gal probe is the first example for the fluorogenic in vivo detection of senescence in urine and may serve as a basis for the development of generalized fluorogenic diagnostic platforms for the easy diagnosis in the urine of different diseases as well as for monitoring therapeutic treatments without the use of expensive equipment or trained personnel.

Cellular senescence is a state of stable cell cycle arrest that can negatively affect the regenerative capacities of tissues and can contribute to inflammation and the progression of various aging-related diseases. Advances in the in vivo detection of cellular senescence are still crucial to monitor the action of senolytic drugs and to assess the early onset or accumulation of senescent cells. Here, we describe a naphthalimide-styrene-based probe (HeckGal) for the detection of cellular senescence both in vitro and in vivo. HeckGal is hydrolyzed by the increased lysosomal β-galactosidase activity of senescent cells, resulting in fluorescence emission. The probe was validated in vitro using normal human fibroblasts and various cancer cell lines undergoing senescence induced by different stress stimuli. Remarkably, HeckGal was also validated in vivo in an orthotopic breast cancer mouse model treated with senescence-inducing chemotherapy and in a renal fibrosis mouse model. In all cases, HeckGal allowed the unambiguous detection of senescence in vitro as well as in tissues and tumors in vivo. This work is expected to provide a potential technology for senescence detection in aged or damaged tissues.

[EN] Cellular senescence is a state of stable cell cycle arrest that can negatively affect the regenerative capacities of tissues and can contribute to inflammation and the progression of various aging-related diseases. Advances in the in vivo detection of cellular senescence are still crucial to monitor the action of senolytic drugs and to assess the early onset or accumulation of senescent cells. Here, we describe a naphthalimide-styrene-based probe (HeckGal) for the detection of cellular senescence both in vitro and in vivo. HeckGal is hydrolyzed by the increased lysosomal beta-galactosidase activity of senescent cells, resulting in fluorescence emission. The probe was validated in vitro using normal human fibroblasts and various cancer cell lines undergoing senescence induced by different stress stimuli. Remarkably, HeckGal was also validated in vivo in an orthotopic breast cancer mouse model treated with senescence-inducing chemotherapy and in a renal fibrosis mouse model. In all cases, HeckGal allowed the unambiguous detection of senescence in vitro as well as in tissues and tumors in vivo. This work is expected to provide a potential technology for senescence detection in aged or damaged tissues., R.M. laboratory members thank the financial support from the Spanish Government (project RTI2018-100910-B-C41) and the Generalitat Valenciana (project PROMETEO 2018/024). B.L.-T. is grateful to the Spanish Ministry of Economy for their PhD grants (FPU15/02707). I.G. thanks her contract from IDM. J.F.-B. thanks to his postdoctoral fellowship (CD19/00038). J.A.L.-D. thanks the financial support from the Ministry of Science/MICINN (IJCI-2017-33047). Work in the laboratory of M.S. was funded by the IRB and by grants from the Spanish Ministry of Economy cofunded by the European Regional Development Fund (ERDF) (SAF201348256-R), the European Research Council (ERC-2014-AdG/669622), and the "laCaixa" Foundation. The D.M.-E. laboratory is supported by the Cancer Research U.K. (CRUK), Cambridge Centre Early Detection Programme, by a CRUK Early Detection OHSU project award (C62187/A26989), by a Medical Research Council (MRC) New Investigators Research Grant (NIRG, MR/R000530/1).

[EN] Benzene is a highly toxic aromatic hydrocarbon. Inhaling benzene can cause dizziness, vertigo, headaches, aplasia, mutations and, in the most extreme cases, cancer. Trans,trans-muconic acid (t,t-MA) is one of the metabolization products of benzene. Although different analytical methods have been reported for the determination of t,t-MA, these are often expensive, require trained personnel, are not suitable for on-site measurements, and use hazardous organic solvents. For these reasons, the development of reliable, selective and sensitive methods for rapid and in situ detection of t,t-MA are of importance. Addressing this challenge, a nanodevice for the selective and sensitive quantification of t,t-MA in urine is reported. The nanodevice used is achieved using mesoporous silica nanoparticles loaded with a dye reporter and capped with a dicopper(II) azacryptand. Pore opening and payload release is induced rapidly (10 min) and selectively with t,t-MA in urine, using a simple fluorimeter without sample pretreatment., The authors thank the Spanish Government (RTI2018-100910-B-C41) and the Generalitat Valenciana (PROMETEO 2018/024) for support.

[EN] In vivo detection of cellular senescence is accomplished by using mesoporous silica nanoparticles loaded with the NIR-FDA approved Nile blue (NB) dye and capped with a galactohexasaccharide (S3). NB emission at 672 nm is highly quenched inside S3, yet a remarkable emission enhancement is observed upon cap hydrolysis in the presence of beta-galactosidase and dye release. The efficacy of the probe to detect cellular senescence is tested in vitro in melanoma SK-Mel-103 and breast cancer 4T1 cells and in vivo in palbociclib-treated BALB/cByJ mice bearing breast cancer tumor., R.M. thanks financial support from the Spanish Government (RTI2018-100910-B-C41 and RTI2018-101599-B-C22 (MCUI/AEI/FEDER, UE)) and the Generalitat Valenciana (PROMETEO 2018/024). M.O. thanks the financial support from SAF2017-84689-R project and MINECO/AEI/FEDER, UE and the Generalitat Valenciana (PROMETEO/2019/065). B.L.-T. is grateful to the Spanish Ministry of Economy for her PhD grant. I.G. thanks her contract from IDM. J.F.-B. and M.A. thank the UPV for their postdoctoral fellowship.

Detecting senescent cells has become a task of increasing importance in recent years. The implication of cellular senescence in a variety of physiological processes as well as in various diseases is the main reason why potential diagnostic tools for senescent cells are sought. This chapter clearly and concisely addresses the discussion of the published tools (molecular based probes and nanocarriers) to carry out the diagnosis of senescent cells both in vitro and in vivo and in tissues. The comprehensive reading of this chapter will allow the reader to overview the advances in the area of the detection of cellular senescence using probes and carriers as diagnostic methods.

[EN] Pharmacologically active compounds with preferential cytotoxic activity for senescent cells, known as senolytics, can ameliorate or even revert pathological manifestations of senescence in numerous preclinical mouse disease models, including cancer models. However, translation of senolytic therapies to human disease is hampered by their suboptimal specificity for senescent cells and important toxicities that narrow their therapeutic windows. We have previously shown that the high levels of senescence-associated lysosomal beta-galactosidase (SA-beta-gal) found within senescent cells can be exploited to specifically release tracers and cytotoxic cargoes from galactose-encapsulated nanoparticles within these cells. Here, we show that galacto-conjugation of the BCL-2 family inhibitor Navitoclax results in a potent senolytic prodrug (Nav-Gal), that can be preferentially activated by SA-beta-gal activity in a wide range of cell types. Nav-Gal selectively induces senescent cell apoptosis and has a higher senolytic index than Navitoclax (through reduced activation in nonsenescent cells). Nav-Gal enhances the cytotoxicity of standard senescence-inducing chemotherapy (cisplatin) in human A549 lung cancer cells. Concomitant treatment with cisplatin and Nav-Gal in vivo results in the eradication of senescent lung cancer cells and significantly reduces tumour growth. Importantly, galacto-conjugation reduces Navitoclax-induced platelet apoptosis in human and murine blood samples treated ex vivo, and thrombocytopenia at therapeutically effective concentrations in murine lung cancer models. Taken together, we provide a potentially versatile strategy for generating effective senolytic prodrugs with reduced toxicities., Royal Society, Grant/Award Number: RG160806; Medical Research Council, Grant/Award Number: MR/R000530/1; Cancer Research UK, Grant/Award Number: C62187/A26989 and C62187/A29760; CRUK Cambridge Centre Early Detection Programme, Grant/Award Number: RG86786

[EN] MIL-101(Cr) having substituents at the terephthalate linker (X = H, NO2, SO3H, Cl, CH3 and NH2) promotes the aerobic oxidation of benzylamines to the corresponding N-benzylidene benzylamines at different rates. MIL-101(Cr)¿NO2 was the most active catalyst, about 6-fold more active than the parent MIL-101(Cr). MIL-101(Cr)¿NO2 does not deactivate significantly upon five consecutive reuses, does not leach the metal to the solution and maintains its crystallinity. MIL-101(Cr)¿NO2 is active for a wide range of benzylamines including para-substituted, heterocyclic benzylamines and di- and tribenzylamines., Financial support by the Spanish Ministry of Economy and Competitiveness (CTQ 2015-69153-CO2-1, CTQ2014-53292-R, Severo Ochoa) and Generalitat Valenciana (Prometeo 2013014) is gratefully acknowledged.

[EN] A series of five isostructural zirconium terephthalate UiO-66 metal organic frameworks bearing different functional groups on the terephthalate linker (UiO-66-X; X = H, NH2, NO2, Br, Cl,) have been successfully prepared and characterized. UiO-66-X materials were evaluated as heterogeneous catalysts for the epoxide ring opening of styrene oxide by methanol, observing an increase in the initial reaction rate from UiO-66-H to UiO-66-Br, over one order of magnitude. The reactivity order, however, does not follow a linear relationship between the Hammett constant value of the substituent and the initial reaction rate. UiO-66-Br exhibits a wide scope, its activity depending on the structure of epoxide and nucleophile. The absence of Zr leaching to the solution together with the preservation of the UiO-66-X crystallinity confirms the stability of the framework under the reaction conditions. Nevertheless, UiO-66 undergoes a progressive deactivation upon reuse that was attributed to a strong adsorption of the reaction product., Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa and CTQ2015-69153 and CTQ2014-53292-R and Generalitat Valenciana (Prometeo 2013/14) and is grateful acknowledged. We also thank EU under the Being Energy contract for partial funding. J.F.B. thanks the Universitat Politecnica de Valencia for a postgraduate scholarship. S.N. thanks the Spanish Ministerio de Educacion, Cultura y Deporte for Jose Castillejo mobility programme (CAS14/00067).

[EN] N-hydroxyphthalimide (NHPI) derived from trimellitic anhydride has been covalently anchored (4wt%) through ester bonds to the surface of commercial diamond nanoparticles previously functionalized by chemical and thermal treatments (DH). IR spectroscopy of the NHPI/DH solid shows the presence of a characteristic peak at 1735cm(-1) attributable to the ester bond, while solid-state MAS (CNMR)-C-13 spectroscopy shows two broad bands corresponding to carbon atoms of carbonyl groups (167ppm) and aromatic carbons (127ppm). NHPI/DH promotes autoxidation of isobutylbenzene involving superoxide (O-2(.-)) and hydroperoxide (HOO) radicals; NHPI/DH can be reused at least three times and reach a minimum turnover number as high as 20600, which is probably due to the inertness of the diamond surface, allowing free diffusion of reactive oxygen species. Analogous materials in which NHPI was anchored on activated carbon and multiwall carbon nanotubes were inefficient as autoxidation catalysts. NHPI/DH is able to promote also selective aerobic oxidation of other benzylic hydrocarbons and cycloalkenes., Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa and CTQ2015-69153-CO2-R1 and CTQ2014-53292-R and Generalitat Valenciana (Prometeo 2013/14) and is grateful acknowledged. S.N. is thankful for financial support by Fundacion Ramon Areces (XVIII Concurso Nacional, Ciencias de la Vida y de la Materia, Energia renovable: materiales y procesos 2016).

Graphene oxide promotes the oxidative degradation of -guaiacylglycerol--guaiacyl ether, a lignin model compound, in different solvents including acetonitrile, toluene and water mainly to guaiacol, 2-methoxyquinone, vanillic acid and coniferyl aldehyde. Reduced graphene oxide and B-doped graphene exhibit similar activity as graphene oxide. Control experiments indicate that metal impurities should play a marginal role in the observed catalytic activity., Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa and CTQ2012-32315) and Generalitat Valenciana (Prometeo 2012-013) is gratefully acknowledged. Partial financial support by the European Union (Novacam project) is also acknowledged. J. F. B. thanks to the Technical University of Valencia for a PhD scholarship.

[EN] Nickel nanoparticles (NPs) supported on different undoped or doped with N or B graphenes (Gs) have been tested as catalyst for the hydrosilylation of aldehydes to obtain the corresponding siloxanes with high conversion and good selectivity in short reaction time. The different Gs employed were obtained by pyrolysis under inert atmosphere of alginate or chitosan, modified or not with boric acid. Then the metal NPs obtained by polyol reduction method using ethylene glycol were adsorbed on Gs. The Ni-containing G catalysts were characterized by electron microscopy, XPS and Raman spectroscopy. The scope of the Ni/G catalyst includes aliphatic and aromatic aldehydes as well as a variety of hydrosilanes. (C) 2015 Elsevier B.V. All rights reserved., Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa and CTQ2012-32315) and Generalitat Valenciana (Prometeo 2013-019) in gratefully acknowledged. J.F.B. and I.E.A. thanks to the Technical University of Valencia and the Spanish Ministry of Economy and Competitiveness for postgraduate scholarships, respectively.

[EN] Metal oxide nanoparticles supported on graphene exhibit high catalytic activity for oxidation, reduction and coupling reactions. Here we show that pyrolysis at 900 C under inert atmosphere of copper(II) nitrate embedded in chitosan films affords 1.1.1 facet-oriented copper nanoplatelets supported on few-layered graphene. Oriented (1.1.1) copper nanoplatelets on graphene undergo spontaneous oxidation to render oriented (2.0.0) copper(I) oxide nanoplatelets on few-layered graphene. These films containing oriented copper(I) oxide exhibit as catalyst turnover numbers that can be three orders of magnitude higher for the Ullmann-type coupling, dehydrogenative coupling of dimethylphenylsilane with n-butanol and C–N cross-coupling than those of analogous unoriented graphene-supported copper(I) oxide nanoplatelets., Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa and CTQ2012-32315) and Generalitat Valenciana (Prometeo 2013-019) is gratefully acknowledged. Partial financial support from European Union (Being Energy project) is also acknowledged. J.F.B. and I. E.-A. thank the Technical University of Valencia and the Spanish Ministry of Science for PhD scholarships, respectively. The authors are grateful to Mrs. Amparo Forneli for her assistance in the sample preparation and to Dr. Agouram Said from SCSIE, University of Valencia for the sample preparation and HRTEM characterization of samples. AD thanks University Grants Commission, New Delhi, for the award of Assistant Professorship under its Faculty Recharge Programme. AD also thanks Department of Science and Technology, India, for the financial support through Fast Track project (SB/FT/CS-166/2013) and the Generalidad Valenciana for financial aid supporting his stay at Valencia through the Prometeo programme. VP thanks UEFISCDI for financial support through PN-II-ID-PCE-2011-3-0060 project (275/2011).

[EN] Copper nanoparticles (NPs) supported on a series of undoped and doped graphene materials (Gs) have been obtained by pyrolysis of alginate or chitosan biopolymers, modified or not with boric acid, containing Cu2+ ions at 900 8C under inert atmosphere. The resulting Cu-G materials containing about 17 wt% Cu NPs (from 10 to 200 nm) exhibit high catalytic activity for the dehydrogenative coupling of silanes with alcohols. The optimal material consisting on Cu- (B)G is more efficient than Cu NPs on other carbon supports, Financial support by the Spanish Ministry of economy and competitiveness (Severo Ochoa and CTQ2012-32315) and Generalitat Valenciana Prometeo 2012-013) is gratefully acknowledged.

Correction for ‘Palladium nanoparticles supported on graphene as catalysts for the dehydrogenative coupling of hydrosilanes and amines’ by Hermenegildo Garcia et al., Catal. Sci. Technol., 2015, DOI: 10.1039/c4cy01486c.