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Small (Weinheim An Der Bergstrasse,... Mar 2023Optical imaging in the second near-infrared (NIR-II, 900-1700 nm) window has been extensively investigated for bioimaging. However, a strong autofluorescence background...
Optical imaging in the second near-infrared (NIR-II, 900-1700 nm) window has been extensively investigated for bioimaging. However, a strong autofluorescence background from real-time excitation light significantly reduces the images' quality of NIR-II fluorescence (FL) imaging. To resolve this issue, a NIR-II self-luminous small molecule (CLPD) based on bioluminescence (BL) resonance energy transfer (BRET) mechanism is first developed. The reactive oxygen species (ROS) can trigger NIR-II BL and reduce the NIR-II FL signals of the CLPD simultaneously, enabling ROS-correlated ratiometric BL/FL imaging. CLPD is used for high-contrast NIR-II BL imaging of osteoarthritis as well as guiding the treatment process by ratiometric BL/FL imaging. Moreover, CLPD is applied for NIR-II BL imaging of tumor triggered by the generated ROS during PDT. A correlation between the ratiometric NIR-II BL/FL signal and tumor size is constructed, providing a trustworthy tool for early assessment of PDT effect. Overall, this study presents a novel NIR-II self-luminous small molecular probe for in vivo imaging and provides a strategy for design a self-evaluation system of therapeutic effect.
Topics: Humans; Molecular Probes; Reactive Oxygen Species; Neoplasms; Inflammation
PubMed: 36534901
DOI: 10.1002/smll.202206666 -
Current Opinion in Chemical Biology Feb 2016High throughput screening (HTS) has historically been used for drug discovery almost exclusively by the pharmaceutical industry. Due to a significant decrease in costs... (Review)
Review
High throughput screening (HTS) has historically been used for drug discovery almost exclusively by the pharmaceutical industry. Due to a significant decrease in costs associated with establishing a high throughput facility and an exponential interest in discovering probes of development and disease associated biomolecules, HTS core facilities have become an integral part of most academic and non-profit research institutions over the past decade. This major shift has led to the development of new HTS methodologies extending beyond the capabilities and target classes used in classical drug discovery approaches such as traditional enzymatic activity-based screens. In this brief review we describe some of the most interesting developments in HTS technologies and methods for chemical probe discovery.
Topics: Drug Discovery; Humans; Molecular Probes; Phenotype; Proteins; Small Molecule Libraries
PubMed: 26615565
DOI: 10.1016/j.cbpa.2015.10.032 -
Journal of Photochemistry and... Sep 2022Nitric oxide (NO) is involved in many biological processes affecting the cardiovascular, nervous and immune systems. Intracellular NO can be monitored using fluorescent...
A highly photostable and versatile two-photon fluorescent probe for the detection of a wide range of intracellular nitric oxide concentrations in macrophages and endothelial cells.
Nitric oxide (NO) is involved in many biological processes affecting the cardiovascular, nervous and immune systems. Intracellular NO can be monitored using fluorescent probes in combination with fluorescence imaging techniques. Most of the currently available NO fluorescent molecular probes are excited via one-photon excitation using UV or Vis light, which results in poor penetration and high photodamage to living tissues. Here, we report a two-photon fluorescent molecular probe, DANPY-NO, able to detect NO in live cells. The probe consists of an o-phenylenediamine linked to a naphthalimide core; and operates via photoinduced electron transfer. DANPY-NO exhibits good sensitivity (LOD of 77.8 nM) and high selectivity towards NO, and is stable over a broad range of pHs. The probe targeted acidic organelles within macrophages and endothelial cells, and demonstrated enhanced photostability over a commercially available NO probe. DANPY-NO was used to selectively detect endogenous NO in RAW264.7ϒ NO macrophages, THP-1 human leukemic cells, primary mouse (bone marrow-derived) macrophages and endothelial cells. The probe was also able to detect exogenous NO in endothelial cells and distinguish between increasing concentrations of NO. The NO detection was evidenced using confocal laser scanning and two-photon microscopies, and flow cytometry. Further evidence was obtained by recording the changes in the intracellular fluorescence emission spectrum of the probe. Importantly, the probe displayed negligible toxicity to the analysed biological samples. The excellent sensitivity, selectivity, stability and versatility of DANPY-NO confirm its potential for in vitro and in vivo imaging of NO.
Topics: Animals; Endothelial Cells; Fluorescent Dyes; HeLa Cells; Humans; Macrophages; Mice; Molecular Probes; Nitric Oxide; Photons
PubMed: 35850002
DOI: 10.1016/j.jphotobiol.2022.112512 -
Nuklearmedizin. Nuclear Medicine 2016Optical imaging has long been considered a method for histological or microscopic investigations. Over the last 15 years, however, this method was applied for... (Review)
Review
Optical imaging has long been considered a method for histological or microscopic investigations. Over the last 15 years, however, this method was applied for preclinical molecular imaging and, just recently, was also able to show its principal potential for clinical applications (e .g. fluorescence-guided surgery). Reviewing the development and preclinical evaluation of new fluorescent dyes and target-specific dye conjugates, these often show characteristic patterns of their routes of excretion and biodistribution, which could also be interesting for the development and optimization of radiopharmaceuticals. Especially ionic charges show a great influence on biodistribution and net-charge and charge-distribution on a conjugate often determines unspecific binding or background signals in liver, kidney or intestine, and other organs. Learning from fluorescent probe behaviour in vivo and translating this knowledge to radiopharmaceuticals might be useful to further optimize emerging and existing radiopharmaceuticals with respect to their biodistribution and thereby availability for binding to their targets.
Topics: Fluorescent Dyes; Microscopy, Fluorescence; Molecular Imaging; Molecular Probe Techniques; Molecular Probes; Optical Imaging; Radiopharmaceuticals; Staining and Labeling
PubMed: 27067793
DOI: No ID Found -
Scientific Reports Oct 2020Redox status influences the course of the inflammatory, metabolic, and proliferative liver diseases. Oxidative stress is thought to play a crucial and sustained role in...
Redox status influences the course of the inflammatory, metabolic, and proliferative liver diseases. Oxidative stress is thought to play a crucial and sustained role in the pathological progression of early steatosis to severe hepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. Oxidative stress induced by reactive oxygen species which are generated in the mitochondria can lead to chronic organelle damage in hepatocytes. Currently, the diagnosis of liver disease requires liver biopsy, which is invasive and associated with complications. The present report describes the development of a novel molecular probe, EDA-PROXYL, with higher reactivity and mitochondrial selectivity than standard carboxyl-PROXYL and carbamoyl-PROXYL probes. The membrane permeability of our probe improved in aqueous environments which led to increased accumulation in the liver and interaction of EDA-PROXYL with the carnitine transporter via the amine (NH) group further increased accumulation. This increased mitochondrial sensitivity and enhanced accumulation highlight the potential of EDA-PROXYL as a molecular probe for determining metabolic reactions of the mitochondria. Thus, this novel probe could be a tool for the evaluation of redox status of the mitochondria to assess the degree of liver injury and, ultimately, the response to pharmacological therapy.
Topics: Animals; Carcinoma, Hepatocellular; Hepatocytes; Liver; Liver Cirrhosis; Liver Neoplasms; Male; Mice; Mice, Inbred C57BL; Mitochondria; Molecular Probes; Oxidation-Reduction; Oxidative Stress; Reactive Oxygen Species
PubMed: 33020535
DOI: 10.1038/s41598-020-73336-1 -
Analytical Chemistry Sep 2020Mercury (Hg) is considered an extremely toxic heavy metal which is extremely harmful to both the human body and environment. In addition, Hg-induced oxidative stress...
Mercury (Hg) is considered an extremely toxic heavy metal which is extremely harmful to both the human body and environment. In addition, Hg-induced oxidative stress also exerts a crucial role to play in pathophysiological mechanisms of mercury toxicity. Thus, efficient and specific fluorescent probes for imaging Hg-induced oxidative stress are necessary. In the present study, we rationally design a novel Hg-activated and ICT-based NIR emission fluorescent probe for sequentially monitoring the ONOO level with a "dual-key-and-lock" strategy. The probe showed rapid response and excellent specificity and sensitivity for the detection of Hg and ONOO in vitro. Cell imaging demonstrated that Hg-induced oxidative stress was involved in ONOO upregulation. Also, GSH, NAC, and EDTA were employed as excellent detoxifying drugs against Hg-induced toxicity. Moreover, the probe was successfully used for imaging Hg and ONOO in vivo. In brief, provides a simple and powerful approach which can be used to image Hg-induced oxidative stress in the pathological environment.
Topics: Animals; Humans; Mercury; Mice; Molecular Probes; Oxidative Stress
PubMed: 32786484
DOI: 10.1021/acs.analchem.0c02509 -
Nature Communications Jun 2018Increased cancer cell motility constitutes a root cause of end organ destruction and mortality, but its complex regulation represents a barrier to precision targeting....
Increased cancer cell motility constitutes a root cause of end organ destruction and mortality, but its complex regulation represents a barrier to precision targeting. We use the unique characteristics of small molecules to probe and selectively modulate cell motility. By coupling efficient chemical synthesis routes to multiple upfront in parallel phenotypic screens, we identify that KBU2046 inhibits cell motility and cell invasion in vitro. Across three different murine models of human prostate and breast cancer, KBU2046 inhibits metastasis, decreases bone destruction, and prolongs survival at nanomolar blood concentrations after oral administration. Comprehensive molecular, cellular and systemic-level assays all support a high level of selectivity. KBU2046 binds chaperone heterocomplexes, selectively alters binding of client proteins that regulate motility, and lacks all the hallmarks of classical chaperone inhibitors, including toxicity. We identify a unique cell motility regulatory mechanism and synthesize a targeted therapeutic, providing a platform to pursue studies in humans.
Topics: Animals; Cell Line, Tumor; Cell Movement; Drug Screening Assays, Antitumor; Female; Flavones; Humans; Male; Membrane Glycoproteins; Mice; Molecular Probe Techniques; Molecular Probes; Neoplasms, Experimental
PubMed: 29934502
DOI: 10.1038/s41467-018-04465-5 -
Current Topics in Medicinal Chemistry 2018Molecular Dynamics (MD) based computational co-solvent mapping methods involve the generation of an ensemble of MD-sampled target protein conformations and using... (Review)
Review
Molecular Dynamics (MD) based computational co-solvent mapping methods involve the generation of an ensemble of MD-sampled target protein conformations and using selected small molecule fragments to identify and characterize binding sites on the surface of a target protein. This approach incorporates atomic-level solvation effects and protein mobility. It has shown great promise in the identification of conventional competitive and allosteric binding sites. It is also currently emerging as a useful tool in the early stages of drug discovery. This review summarizes efforts as well as discusses some methodological advances and challenges in binding site identification process through these co-solvent mapping methods.
Topics: Animals; Binding Sites; Humans; Molecular Dynamics Simulation; Molecular Probes; Protein Conformation; Proteins; Small Molecule Libraries; Surface Properties
PubMed: 30499401
DOI: 10.2174/1568026619666181130120308 -
Molecules (Basel, Switzerland) Jul 2023Human exposure to dicarbonyls occurs via ingestion (e.g., food), inhalation (e.g., electronic cigarettes) and dysregulation of endogenous metabolic pathways (e.g.,...
Human exposure to dicarbonyls occurs via ingestion (e.g., food), inhalation (e.g., electronic cigarettes) and dysregulation of endogenous metabolic pathways (e.g., glycolysis). Dicarbonyls are electrophiles able to induce carbonylation of endogenous substrate. They have been associated with the onset and progression of several human diseases. Several studies have advocated the use of dicarbonyl binders as food preservatives or as drugs aimed at mitigating carbonylation. This study presents the setup of an easy and cheap assay for the screening of selective and potent dicarbonyl binders. The method is based on the incubation of the candidate molecules with a molecular probe. The activity is then determined by measuring the residual concentration of the molecular probe over time by liquid chromatography (LC). However, the naturally occurring dicarbonyls (e.g., glyoxal, methylglyoxal) are not appealing as probes since they are hard to separate and detect using the most popular LC variants. Benzylglyoxal (BGO) was therefore synthesized and tested, proving to be a convenient probe that allows a direct quantification of residual dicarbonyls by reversed phase LC without derivatization. The method was qualified by assessing the binding ability of some molecules known as binders of natural occurring dicarbonyls, obtaining results consistent with literature.
Topics: Humans; Electronic Nicotine Delivery Systems; Glyoxal; Pyruvaldehyde; Chromatography, Liquid; Molecular Probes
PubMed: 37513213
DOI: 10.3390/molecules28145341 -
Hepatobiliary & Pancreatic Diseases... Jun 2019Clear tumor imaging is essential to the resection of hepatocellular carcinoma (HCC). This study aimed to create a novel biological probe to improve the HCC imaging.
BACKGROUND
Clear tumor imaging is essential to the resection of hepatocellular carcinoma (HCC). This study aimed to create a novel biological probe to improve the HCC imaging.
METHODS
Au nano-flower particles and CuInS-ZnS core-shell quantum dots were synthesized by hydrothermal method. Au was coated with porous SiO and combined with anti-AFP antibody. HCC cell line HepG2 was used to evaluate the targeting efficacy of the probe, while flow cytometry and MTT assay were used to detect the cytotoxicity and bio-compatibility of the probe. Probes were subcutaneously injected to nude mice to explore light intensity and tissue penetration.
RESULTS
The fluorescence stability of the probe was maintained 100% for 24 h, and the brightness value was 4 times stronger than that of the corresponding CuInS-ZnS quantum dot. In the targeting experiment, the labeled HepG2 emitted yellow fluorescence. In the cytotoxicity experiments, MTT and flow cytometry results showed that the bio-compatibility of the probe was fine, the inhibition rate of HepG2 cell with 60% Cu-QDs/Anti-AFP probe and Au-QDs/Anti-AFP probe solution for 48 h were significantly different (86.3%±7.0% vs. 4.9%±1.3%, t = 19.745, P<0.05), and the apoptosis rates were 83.3%±5.1% vs. 4.4%±0.8% (P<0.001). In the animal experiment, the luminescence of the novel probe can penetrate the abdominal tissues of a mouse, stronger than that of CuInS-ZnS quantum dot.
CONCLUSIONS
The Au@SiO@CuInS-ZnS/Anti-AFP probe can targetedly recognize and label HepG2 cells with good bio-compatibility and no toxicity, and the strong tissue penetrability of luminescence may be helpful to surgeons.
Topics: Animals; Carcinoma, Hepatocellular; Hep G2 Cells; Humans; Injections, Subcutaneous; Liver Neoplasms; Mice, Inbred BALB C; Mice, Nude; Molecular Imaging; Molecular Probes; Nanoparticles; Optical Imaging; Quantum Dots; Tissue Distribution; alpha-Fetoproteins
PubMed: 30879890
DOI: 10.1016/j.hbpd.2019.03.001