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1.
J Am Chem Soc ; 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32130860

RESUMO

Glutathione (GSH) mediates a wide variety of biological events and human diseases. Although it has been the subject of intense study in recent years, a further understanding of its molecular mechanisms and metabolism routes in living cells has remained limited due to a lack of appropriate analytical tools. Sulfur dioxide (SO2), an important metabolite of GSH, is usually associated with the symptoms of neurological disorders, cardiovascular diseases, and lung cancer. Herein, a novel multisignal fluorescent probe was rationally designed and exploited for the simultaneous detection of GSH and its metabolite SO2 via an ICT-FRET synergetic mechanism. The probe shows completely reversed fluorescence responses toward GSH (enhanced red emission) and SO2 (annihilated red fluorescence) with high selectivity and sensitivity. In particular, the probe displayed completely different fluorescent signals (blue-shift) with SO2 in the presence of GSH, thereby allowing the imaging of the metabolism process of GSH to SO2 in two independent channels without spectral cross interference. Given these advantages, this probe has been successfully applied to the real-time monitoring of the SO2 metabolic process in living cells and mice models, and it has thus been found that GSH can metabolize SO2 by enzymatic reaction with TST (thiosulfate sulphurtransferase); additionally, SO2 was transformed into sulfate under SUOX (sulfite oxidase). We anticipate that this research will provide a convenient and efficient tool for understanding the interrelated physiological functions of GSH and SO2 in more biosystems.

2.
J Am Chem Soc ; 142(6): 3262-3268, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31951702

RESUMO

Heat stroke (HS) can cause serious organism damage or even death. Early understanding of the mechanism of heat cytotoxicity can prevent or treat heat stroke related diseases. In this work, probe Ly-NT-SP was synthesized, characterized, and used for sulfur dioxide (SO2) detection in lysosomes. PBS solutions of probe Ly-NT-SP at pH 5.0 present a marked broad emission band in the green zone (535 nm). After UV irradiation, the spiropyran group in Ly-NT-SP isomerizes to the merocyanine form (Ly-NT-MR), which presented a weak red-shifted emission at 630 nm. In addition, photocontrolled isomerization of Ly-NT-SP to Ly-NT-MR generated a C═C-C═N+ fragment able to react, through a Michael addition, with SO2 to yield a highly emissive adduct with a marked fluorescence in the green channel (535 nm). In vitro studies showed a remarkable selectivity of photoactivated Ly-NT-MR to SO2 with a limit of detection as low as 4.7 µM. MTT viability assays demonstrated that the Ly-NT-SP is nontoxic to HeLa cells and can be used to detect SO2 in lysosomes. Taking advantage of this, the sensor is successfully applied to image increasing SO2 values in lysosomes during heat shock for the first time. Moreover, we also confirmed that the increased SO2 can protect the small intestine against damage induced by heat shock through regulating oxidative stress in cells and mice.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 118001, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31935657

RESUMO

Hypochlorous acid, a type of reactive oxygen species, has been shown to play an important role in organisms. Nowadays, there are many kinds of fluorescence detecting mechanisms to detect hypochlorous acid in vivo. Due to the high selectivity, the mechanism of using the strong oxidation of hypochlorous acid to break carbon­carbon double bonds has been favored by many scientists. However, the reported probes of breaking carbon­carbon double bonds still had drawback such as slow response. Based on this, we introduced electron-withdrawing group malonitrile to accelerate the oxidation of hypochlorous acid, resulting in reaction time less than 150 s. Meanwhile, the probe exhibited excellent selectivity, optical stability, high sensitivity and the detection limit as low as 0.19 µM. More importantly, we also successfully proved the potential application of the probe for the detection of intracellular ClO- living cells and Arabidopsis root tip by fluorescence imaging.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 227: 117537, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31690486

RESUMO

The development of fluorescent probes enabling distinguishable detection Cys, Hcy, GSH and H2S is still a considerable challenge owing to their similar functional group with comparable reactivity. In this work, a novel fluorescent probe FHC-O-NBD has been synthesized, and a practicable strategy for the fluorescence discrimination of Cys/Hcy and GSH/H2S, especially the colorimetric detection for H2S have been presented. FHC-O-NBD reacted with Cys/Hcy to produce two fluorescent emissions at 486 nm and 550 nm, while for GSH/H2S, only one fluorescent signal at 486 nm appeared. And, only upon addition of H2S, the color of the system changed from colorless to pink. So it can serve as a colorimetric probe for H2S by "naked eye". Furthermore, FHC-O-NBD can selectively distinguish Cys/Hcy and GSH/H2S in living cells, meaning it has great potential in biological applications.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 225: 117517, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31521001

RESUMO

Alterations of the homeostasis balance of cysteine (Cys) are associated with a variety of diseases and cellular functions, and therefore, Cys dynamic real-time living cell intracellular imaging and quantification are important for understanding the pathophysiological processes. Thus, Cys probe that can permeate high efficiently is the first one to be affected. In fact, it is difficult for organic molecular probes to infiltrate cells because of the unique structure of the cell membrane. In this work, we found that probe containing-carboxyl just stagnated in cytomembrane due to carboxyl of probe and amino group of membrane protein forming peptide chains, nevertheless, the addition of NEM, improved membrane permeability by NEM reacting with sulfhydryl of membrane protein, which made probe permeate high efficiently and sequentially real-time detect the Cys in cytoplasm. It is the first time noted that NEM can regulate Cys probe containing-carboxyl for high efficient detection in cytoplasm. Additionally, probe was successfully applied to image Cys in mouse.

6.
J Am Chem Soc ; 142(3): 1614-1620, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31887253

RESUMO

Understanding the pathological process of biological systems can greatly improve the prevention and treatment of diseases. The study of pathological processes has now reached the molecular level, and molecular fluorescent probes have become a powerful tool. Chromene, also known as benzo-pyran molecule, is a structural element of natural products with good biological compatibility and was developed as a fluorescent probe. The thiol-chromene "click" nucleophilic pyran ring-opening reaction allows the quick detection of thiol. In this work, the chromene alcohol can function as an efficient self-immolative spacer, which covalently links NIR fluorophore via a carbonyl ester. Due to its favorable characteristics and superior applicability, the self-immolative amplifier NIR-HMPC achieves the specific, rapid, sensitive, NIR fluorescent detection of thiols. Furthermore, the indoles iodized salt in the system can specifically target thiols in mitochondria. Thus, this probe was used to visualize the fluctuations of thiols during oxidative stress and cell apoptosis, cerebral ischemia reperfusion, demonstrating that it is valuable for elucidating pathophysiology process in living organism. This discovery provides an effective means for studying the pathological process of thiol related diseases.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 117905, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31865108

RESUMO

Water pollution is the main cause of death of aquatic organisms such as fish et al. Content of thiophenols in water samples is an important indicator for assessing the degree of water pollution. The development of fluorescent probes with high selectivity and high sensitivity to detect thiophenols in water samples is extremely important in both environmental and life sciences. Although several fluorescent probes for thiophenols detection have been reported in recent years, most of them required the assistance of organic solvents to remedy the restriction caused by the poor water solubility of the probe, which did not fully reflect the actual situation of thiophenols in actual water samples. To fully overcome this shortage, we modified the 1,8-naphthylimide moiety with carboxyl to obtain a water-soluble fluorescent probe which could react with thiophenols specifically through nucleophilic aromatic substitution reaction (SNAr) reaction with turn-on fluorescent responses. The corresponding detection limit was 71 nM. Supported by the spectroscopic changes, test strips based on the probe could detect thiophenols quantificationally and conveniently. At the same time, the probe could detect thiophenols in water sample with quantitative recovery. Besides, cell imaging experiments demonstrated the possibility of the probe to detect thiophenols in living cells.

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 117987, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887682

RESUMO

Statins, as the most commonly drugs could reduce the concentration of low-density lipoprotein cholesterol, have been proved to elevate the H2S generation in cells. Besides, the abnormal levels of biothiols might lead to cancer. Therefore, it is worth considering how to combine the characteristics of the two diseases to realize the detection of cancer cells. Based on this view, we developed a multiresponse fluorescent probe for the detection of hydrogen sulfide (H2S) and biothiols successively based on theoretical calculation. It is interesting that the fluorescence intensity of the probe reacting H2S and biothiols successively was significantly higher than that of probe reacting either of them. Based on this view, we further explored the biological application of the probe and found that the probe had obvious signal response to cancer cells than the normal cells in the presence of fluvastatin. This interesting finding might provide a new insight into cancer cell recognition.

9.
Anal Chem ; 91(23): 15057-15063, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31657199

RESUMO

The activation and execution of cancer invasion and metastasis involves a complex network of intracellular and extracellular molecule levels (such as reactive oxygen species (ROS), matrix metalloproteinases (MMPs)) and signaling cascades. Fluorescence sensing is a powerful detection tool for analytes. However, for imaging the intracellular signal cascades involving multiple molecules, traditional fluorescence probes are unsuitable, because most of them can only determine the change of species rather than response of multiple species simultaneously. Herein we constructed a novel probe: a H2O2-responding fluorophore donor was linked to a MMP2-sensitive peptide tagged with a FRET Cy5 acceptor. Upon addition of H2O2, the system was subjected to green fluorescence emission (555 nm), further triggering a brighter red fluorescent emission (672 nm, belonging to Cy5 acceptor), owing to FRET. In contrast, in the presence of MMP2, the FRET was turned off, due to the special cleavage of the peptide linker. The stimulation with H2O2 made the probe-loaded living cells emit multicolor fluorescence, mainly red fluorescence in normal RAW264.7 cells and poorly invasive MCF7 cells, and only green fluorescence in highly invasive MDA-MA-231 cells, owing to overexpressed MMP2. This means that after the activation with H2O2, the probe can be used to distinguish MDA-MA-231 cells from RAW264.7 macrophages and MCF7 cells. Therefore, this multicolor fluorescent probe is a powerful tool in monitoring cancer invasion and metastasis, which will provide precision information for cancer control and cure.

10.
J Fluoresc ; 29(5): 1241-1248, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31612344

RESUMO

The identification of thiols has become a research hotspot due to its role in biological systems. In this work, we simply constructed a turn-on fluorescent probe named 3-(5-bromopyridin-3-yl)-1-(pyren-1-yl) prop-2-en-1-one, that a combination of pyrene ring and substituted pyridine via the connection of α, ß-unsaturated ketone. Cys can destroy the space effect by Michael addition reaction, which makes the fluorescence intensity changes. Furthermore, the probe featured excellent selectivity and high sensitivity (the detection limit was 0.52 µM) by addition of Cys. Moreover, this probe suggested a potential for imaging in vivo owing to the successful imaging of the probe in HepG2 cells, zebrafish, and Arabidopsis thaliana.

11.
J Mater Chem B ; 7(43): 6855-6860, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31613293

RESUMO

Few studies determined the role of intracellular labile Ca2+ in H2S homeostasis. Undoubtedly, fluorescent probes are powerful tools for exploring the question because of their unique advantages: non-destruction, visualization, and multi-levels imaging. Herein, a near-infrared (λem = 687 nm) and methylene blue chromophore-based fluorescent probe (MB1) for H2S was rationally developed. Based on its high sensitivity and selectivity, MB1 was employed to image the concentration change of H2S, upon stimulating it with ionomycin (a specific calcium ionophore). We found that the intracellular labile Ca2+ acted as a promotor for H2S production in living cells. Furthermore, cystathionine γ-lyase (CSE) might have functioned as a positive mediator of Ca2+-dependent H2S production. These direct and visible links for H2S/Ca2+ will help us to understand the complex signaling in a better way.

12.
Acta Biomater ; 97: 597-607, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31398472

RESUMO

An effective treatment for peri-implantitis is to completely remove all the bacterial deposits from the contaminated implants, especially the organic residues, to regain biocompatibility and re-osseointegration, but none of the conventional decontamination treatments has achieve this goal. The photocatalytic activity of TiO2 coating on titanium implants to degrade organic contaminants has attracted researchers' attention recently. But a pure TiO2 coating only responses to harmful ultraviolet light. Additionally, the poor coating mechanical properties are unable to protect the coating integrity versus initial mechanical decontamination. To address these issues, a unique TiO2 nanoceramic coating was fabricated on titanium substrates through an innovative plasma electrolytic oxidation (PEO) based procedure, which showed a disordered layer with oxygen vacancies on the outmost part. As a result, the coating could decompose methylene blue, rhodamine B, and pre-adsorbed lipopolysaccharide (LPS) under visible light. Additionally, the coating showed two-fold higher hardness than untreated titanium and excellent wear resistance against steel decontamination instruments, which could be attributed to the specific micro-structure, including the densely packed nanocrystals and good metallurgical combination. Moreover, the in vitro response of MG63 cells confirmed that the coating had comparable biocompatibility and osteoconductivity to untreated titanium substrates. This study provides a unique coating technique as well as a photocatalytic cleaning strategy to enhance decontamination of titanium dental implants, which will favour the development of peri-implantitis treatments. STATEMENT OF SIGNIFICANCE: The treatment of peri-implantitis is based on the complete removal of bacterial deposits, especially the organic residues, but conventional decontamination treatments are hard to achieve it. The photocatalytic activity of TiO2 coating on titanium implants to degrade organic contaminants provides a promising strategy for deeper decontamination, but its nonactivation to visible light and poor mechanical properties have limited its application. To address these issues, a unique TiO2 nanoceramic coating was fabricated on titanium substrates based on plasma electrolytic oxidation. The coating showed enhanced visible-light photocatalytic activity, excellent wear resistance and satisfied biocompatibility. Based on this functional coating, it is promising to develop a more efficient strategy for deep decontamination of implant surface, which will favour the development of peri-implantitis treatments.

13.
Chem Soc Rev ; 48(15): 4336-4337, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31282907

RESUMO

Correction for 'Functional synthetic probes for selective targeting and multi-analyte detection and imaging' by Yongkang Yue et al., Chem. Soc. Rev., 2019, DOI: 10.1039/c8cs01006d.

14.
Spectrochim Acta A Mol Biomol Spectrosc ; 223: 117350, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31306961

RESUMO

The intracellular pH has a significant effect on several essential biological processes such as material transfer, enzymatic action, cell apoptosis et al. Thus, it is necessary to monitor pH fluctuation in living cells. Here, we designed a near-infrared ratiometric fluorescence probe for pH detection. The spectroscopic responses of probe to pH variations were investigated in CH3OH/PBS (v/v, 1:1) mixed solution at different pH values. The experimental results showed that the probe is sensitive to acidity, and the pKa of probe is calculated to be 4.85. When the pH was decreased from 9.0 to 1.0, the color of probe solution change from purple to yellow was found by naked eye. Moreover, the probe can be a practical tool for assessing cellular pH by cell imaging.


Assuntos
Benzopiranos/química , Corantes Fluorescentes/química , Indóis/química , Nitrocompostos/química , Espectroscopia de Luz Próxima ao Infravermelho , Células A549 , Sobrevivência Celular , Corantes Fluorescentes/síntese química , Humanos , Concentração de Íons de Hidrogênio , Espectroscopia de Prótons por Ressonância Magnética , Solventes , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Fatores de Tempo
15.
Chem Soc Rev ; 48(15): 4155-4177, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31204740

RESUMO

In contrast to the classical design of a probe with one binding site to target one specific analyte, probes with multiple interaction sites or, alternatively, with single sites promoting tandem reactions to target one or multiple analytes, have been developed. They have been used in addressing the inherent challenges of selective targeting in the presence of structurally similar compounds and in complex matrices, as well as the visualization of the in vivo interaction or crosstalk between the analytes. Examples of analytes include reactive sulfur species, reactive oxygen species, nucleotides and enzymes. This review focuses on recent innovations in probe design, detection mechanisms and the investigation of biological processes. The vision is to promote the ongoing development of fluorescent probes to enable deeper insight into the physiology of bioactive analytes.

16.
Org Lett ; 21(13): 5277-5280, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31247742

RESUMO

Herein, a novel fluorescent probe by integrating 4-azide-1,8-naphthalic anhydride and spiropyran was obtained. NT-N3-SP was capable of specifically monitoring H2S by azide reduced. Upon irradiation by alternate ultraviolet and visible light, both the structure and emission of spiropyran moiety in NT-N3-SP can be reversibly tuned. Importantly, the alternation will be interrupted in the presence of SO2. Additionally, NT-N3-SP was successfully used for detection of H2S/SO2 in cells and mice.

17.
Dent Mater ; 35(9): 1238-1253, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31201017

RESUMO

OBJECTIVE: Periodontal tissue engineering is an attractive approach for restoring periodontal-supporting structures and functions. However, complete periodontal regeneration has not been accomplished. Previous studies demonstrated the feasibility of using cell sheets and treated dentin matrix (TDM) to regenerate bio-roots. METHODS: In this study, we regenerated periodontal tissue using cell sheets combined with TDM particles (TDMPs). Human dental follicle cells (hDFCs) were isolated and characterized. Human dental follicle cells sheets (hDFCSs) and human TDMPs (hTDMP) were fabricated and characterized. The osteogenic effect of hTDMP was evaluated on human bone marrow stromal cells (hBMSCs) in vitro and a rat calvarial bone defect in vivo. Real-time PCR, western blotting, radiograph analysis, and histological analysis were performed to evaluate the periodontal induction capacity of hTDMP. One-wall periodontal intrabony defects were prepared to evaluate the periodontal regeneration capacity of TDMP/DFCSs on beagle dogs. RESULTS: The results showed that hDFCs were mesenchymal stem cells. hTDMP promoted the proliferation and osteogenic differentiation of hBMSCs. New bone formation was observed in the rat calvarial bone defect zone in both the hTDMP and hydroxyapatite/ß-tricalcium phosphate groups. Periodontal-like tissues showed better regeneration in the canine TDMP+DFCS group than in the other groups. SIGNIFICANCE: These results demonstrate the potential of using TDMP/DFCSs in periodontal regeneration.


Assuntos
Saco Dentário , Osteogênese , Animais , Diferenciação Celular , Dentina , Cães , Humanos , Ligamento Periodontal , Ratos , Regeneração
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 221: 117156, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31153120

RESUMO

Biological species analyses on account of fluorescence detection technology are receiving increasing attention, because they combine the advantages both powerful detection capability and excellent imaging technology. By effectively integrating isophorone and phosphate group via p-hydroxybenzaldehyde, the alkaline phosphatase (ALP) detection probe was obtained. Based on the enzyme-catalyzed dephosphorization course, phosphate group was separated from the probe by ALP and released yellow fluorescence signal. Upon addition with ALP, the probe exhibited high selectivity, short response time (6 min) and longer emission peak shift (570 nm). Furthermore, bioimaging experiment results indicated that the probe could detect endogenous ALP effectively.


Assuntos
Fosfatase Alcalina/análise , Cicloexanonas/química , Corantes Fluorescentes/química , Corantes Fluorescentes/toxicidade , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Imagem Molecular/métodos , Fosfatos/química , Sensibilidade e Especificidade , Solubilidade , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Fatores de Tempo
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 220: 117148, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31141776

RESUMO

Fluorescence detection of sulfur dioxide has attracted great interest from researchers in recent years. Usually double bonds and aldehyde group were employed as reaction sites for sulfur dioxide. In this work, the double bond was linked with cyano and carboxyl group as dual electron-withdrawing to enhance the reaction reactivity between the probe and sulfite. Meanwhile, coumarin with good biocompatibility was introduced as fluorophore. Thus D-π-A form constructs intramolecular charge transfer (ICT), the probe has weak yellow fluorescence emission (565 nm), after addition reaction taking place between the probe and bisulfate, conjugated double bond is broken, the system showed a short-wavelength fluorescence emission (483 nm). All these realized a ratiometric fluorescence detection for bisulfate. The study found that dual electron-withdrawing groups enhanced the specificity and sensibility (with a low detection limit 82 nM) of the probe recognizing bisulfate. These excellent properties led directly to the use of probes to image sulfur dioxide in living cells. Further applications are still being on the way.


Assuntos
Corantes Fluorescentes/química , Imagem Molecular/métodos , Dióxido de Enxofre/análise , Acetatos/química , Cumarínicos/química , Elétrons , Corantes Fluorescentes/síntese química , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Sensibilidade e Especificidade , Solubilidade , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Sulfatos/análise , Sulfitos/metabolismo
20.
J Fluoresc ; 29(3): 619-626, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30963368

RESUMO

We designed and synthesized a simple fluorescent probe, (E)-2-(2-(3,4,5-Trimethoxybenzylidene)hydrazinyl) benzothiazole (probe), which could be applied to the detection of strongly acidic and alkaline pH in DMSO/water (1/4, v/v) system. It could be used to quantitatively detect strong acid in the range of 2.60-3.53 with a pKa of 2.78. Meanwhile, it also showed an excellent linear relationship between the fluorescence intensity and alkaline pH values over the range of 9.98-10.95 with a pKa of 9.32. The probe exhibited excellent properties to pH with high selectivity and sensitivity. The mechanism studies showed that the H+ binding with the N atom of benzothiazole moiety and hydrazine moiety in acid solution while the deprotonation of N atom in hydrazine group in basic environment. Importantly, the probe was successfully applied for imaging the strongly acidic and alkaline in E.coil cells.


Assuntos
Escherichia coli/citologia , Corantes Fluorescentes/química , Benzotiazóis/química , Escherichia coli/química , Imagem Óptica
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