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Theranostics 2023Lipid droplets (LDs) are critical organelles associated with many physiological processes in eukaryotic cells. To visualize and study LDs, fluorescence imaging...
Lipid droplets (LDs) are critical organelles associated with many physiological processes in eukaryotic cells. To visualize and study LDs, fluorescence imaging techniques including the confocal imaging as well as the emerging super-resolution imaging of stimulated emission depletion (STED), have been regarded as the most useful methods. However, directly limited by the availability of advanced LDs fluorescent probes, the performances of LDs fluorescence imaging are increasingly unsatisfied with respect to the fast research progress of LDs. We herein newly developed a superior LDs fluorescent probe named as a powerful tool for LDs fluorescence imaging and biological study. Colocalization imaging of and LDs fluorescent probe Ph-Red was conducted in four cell lines. The LDs staining selectivity and the photostability of were also evaluated by comparing with the commercial LDs probe Nile Red. The in-situ fluorescence lifetime of in LDs was determined by time-gated detection. The cytotoxicity of was assessed by MTT assay. The STED saturation intensity as well as the power- and gate time-dependent resolution were tested by Leica SP8 STED super-resolution nanoscopy. The time-lapse 3D confocal imaging and time-lapse STED super-resolution imaging were then designed to study the complex physiological functions of LDs. Featuring with the advantages of the super-photostability, high LDs selectivity, long fluorescence lifetime and low STED saturation intensity, the fluorescent probe was capable of the long-term time-lapse three-dimensional (3D) confocal imaging to in-situ monitor LDs in 3D space and the time-lapse STED super-resolution imaging (up to 500 STED frames) to track the dynamics of LDs with nanoscale resolution (37 nm). Based on the state-of-the-art fluorescence imaging results, some new biological insights into LDs have been successfully provided. For instance, the long-term time-lapse 3D confocal imaging has surely answered an important and controversial question that the number of LDs would significantly decrease rather than increase upon starvation stimulation; the time-lapse STED super-resolution imaging with the highest resolution has impressively uncovered the fission process of nanoscale LDs for the first time; the starvation-induced change of LDs in size and in speed has been further revealed at nanoscale by the STED super-resolution imaging. All of these results not only highlight the utility of the newly developed fluorescent probe but also significantly promote the biological study of LDs.
Topics: Molecular Probes; Microscopy, Fluorescence; Fluorescent Dyes; Lipid Droplets; Optical Imaging
PubMed: 36593956
DOI: 10.7150/thno.79052 -
Spectrochimica Acta. Part A, Molecular... Jun 2023Hydrazine (NH) can cause serious damage to human health, while intracellular viscosity is highly associated with many diseases and cellular dysfunctions. Herein, we...
Hydrazine (NH) can cause serious damage to human health, while intracellular viscosity is highly associated with many diseases and cellular dysfunctions. Herein, we report the synthesis of a dual-responsive organic molecule-based fluorescent probe with excellent water solubility being capable of detection of NH and viscosity through dual-fluorescence channels in "turn on" manner for both. Besides sensitive detection of NH in aqueous solution with detection limit of 0.135 μM, this probe could be used for vapor NH detection in colorimetric and fluorescent manners. In addition, the probe demonstrated viscosity-dependent fluorescence enhancement behavior, and as high as 150-fold enhancement could be obtained at 95% glycerol aqueous solution. Cell imaging experiment revealed that the probe could be used for the discriminating of living and dead cells.
Topics: Humans; Molecular Probes; Water; Viscosity; Spectrometry, Fluorescence; Fluorescent Dyes; Hydrazines; HeLa Cells
PubMed: 36863083
DOI: 10.1016/j.saa.2023.122558 -
Cell Chemical Biology Oct 2017Mitochondrial superoxide (O) underlies much oxidative damage and redox signaling. Fluorescent probes can detect O, but are of limited applicability in vivo, while in...
Mitochondrial superoxide (O) underlies much oxidative damage and redox signaling. Fluorescent probes can detect O, but are of limited applicability in vivo, while in cells their usefulness is constrained by side reactions and DNA intercalation. To overcome these limitations, we developed a dual-purpose mitochondrial O probe, MitoNeoD, which can assess O changes in vivo by mass spectrometry and in vitro by fluorescence. MitoNeoD comprises a O-sensitive reduced phenanthridinium moiety modified to prevent DNA intercalation, as well as a carbon-deuterium bond to enhance its selectivity for O over non-specific oxidation, and a triphenylphosphonium lipophilic cation moiety leading to the rapid accumulation within mitochondria. We demonstrated that MitoNeoD was a versatile and robust probe to assess changes in mitochondrial O from isolated mitochondria to animal models, thus offering a way to examine the many roles of mitochondrial O production in health and disease.
Topics: Animals; Biological Transport; Cell Line; DNA; Male; Mass Spectrometry; Mice; Mitochondria; Models, Molecular; Molecular Probes; Nucleic Acid Conformation; Oxidation-Reduction; Superoxides
PubMed: 28890317
DOI: 10.1016/j.chembiol.2017.08.003 -
Neuroscience Letters Jan 2020Magnetic resonance molecular imaging, as a safe imaging technology, provides a new idea for the early qualitative and hierarchical diagnosis of gliomas. The purpose of...
Magnetic resonance molecular imaging, as a safe imaging technology, provides a new idea for the early qualitative and hierarchical diagnosis of gliomas. The purpose of this study was to design and evaluate the value of neuropilin-1 (NRP-1) targeting molecular probes in the hierarchical diagnosis of gliomas. First, we created an NRP-1 targeted magnetic resonance molecular probe (USPIO-PEG-tLyP-1) by combining the polypeptide tLyP-1 with ultra-small superparamagnetic iron oxide nanoparticles (USPIONs), detecting the physical properties by transmission electron microscopy (TEM) and dynamic light scattering (DLS). Second, in vivo experiments, we established two different degrees of malignant gliomas in-situ in nude mice by injecting U87 and CHG-5 cells. Then, to detect the binding ability of the probe with different grades of tumour tissues, we injected the probe into the tumour-bearing mice through the tail vein. Next, MRI was performed before injection, and 6 h, 12 h, 24 h after injection, and we found significantly more iron particles in the tumour tissues of U87 tumour-bearing mice than in tumour tissues of CHG-5 tumour-bearing mice. The signal intensities of the T2-weighted images of the tumour tissues of each group as well as microscopic observations by Prussian blue staining indicated that the binding ability of this molecular probe to U87 glioma (HGG) with high NRP-1 expression was significantly greater than that of CHG-5 glioma (LGG) with low NRP-1 expression (P < 0.01). Therefore, this study confirms that the novel molecular probe USPIO-PEG-tLyP-1 can be used for the grading diagnosis by MRI for gliomas of high and low grade with different NRP-1 expression levels.
Topics: Animals; Cell Line, Tumor; Cell-Penetrating Peptides; Contrast Media; Dextrans; Dynamic Light Scattering; Glioma; Magnetic Resonance Imaging; Magnetite Nanoparticles; Mice; Mice, Nude; Microscopy, Electron, Transmission; Molecular Probes; Neoplasm Grading; Neuropilin-1; Peptides, Cyclic; Polyethylene Glycols; RNA Interference; Transfection
PubMed: 31705924
DOI: 10.1016/j.neulet.2019.134617 -
Critical Reviews in Food Science and... 2023Antibiotic contamination is becoming a prominent global issue. Therefore, sensitive, specific and simple technology is desirable the demand for antibiotics detection.... (Review)
Review
Antibiotic contamination is becoming a prominent global issue. Therefore, sensitive, specific and simple technology is desirable the demand for antibiotics detection. Biosensors based on split aptamer has gradually attracted extensive attention for antibiotic detection due to its higher sensitivity, lower cost, false positive/negative avoidance and flexibility in sensor design. Although many of the reported split aptamers are antibiotics aptamers, the acquisition and mechanism of splitting is still unknow. In this review, six reported split aptamers in antibiotics are outlined, including Enrofloxacin, Kanamycin, Tetracycline, Tobramycin, Neomycin, Streptomycin, which have contributed to promote interest, awareness and thoughts into this emerging research field. The study introduced the pros and cons of split aptamers, summarized the assembly principle of split aptamer and discussed the intermolecular binding of antibiotic-aptamer complexes. In addition, the recent application of split aptamers in antibiotic detection are introduced. Split aptamers have a promising future in the design and development of biosensors for antibiotic detection in food and other field. The development of the antibiotic split aptamer meets many challenges including mechanism discovery, stability improvement and new biosensor development. It is believed that split aptamer could be a powerful molecular probe and plays an important role in aptamer biosensor.
Topics: Anti-Bacterial Agents; Aptamers, Nucleotide; Biosensing Techniques; Molecular Probes
PubMed: 35507474
DOI: 10.1080/10408398.2022.2064810 -
Theranostics 2017The precision oncology significantly relies on the development of multifunctional agents to integrate tumor targeting, imaging and therapeutics. In this study, a first...
The precision oncology significantly relies on the development of multifunctional agents to integrate tumor targeting, imaging and therapeutics. In this study, a first small-molecule theranostic probe, RhoSSCy is constructed by conjugating 5'-carboxyrhodamines (Rho) and heptamethine cyanine IR765 (Cy) using a reducible disulfide linker and pH tunable amino-group to realize thiols/pH dual sensing. experiments verify that RhoSSCy is highly sensitive for quantitative analysis and imaging intracellular pH gradient and biothiols. Furthermore, RhoSSCy shows superb tumor targeted dual-modal imaging via near-infrared fluorescence (NIRF) and photoacoustic (PA). Importantly, RhoSSCy also induces strongly reactive oxygen species for tumor photodynamic therapy (PDT) with robust antitumor activity both and . Such versatile small-molecule theranostic probe may be promising for tumor targeted imaging and precision therapy.
Topics: Adenocarcinoma; Animals; Disease Models, Animal; Humans; MCF-7 Cells; Mice, Inbred BALB C; Molecular Probes; Photochemotherapy; Photosensitizing Agents; Treatment Outcome
PubMed: 28638467
DOI: 10.7150/thno.18437 -
Cell Chemical Biology Jan 2016The chaperome is a large and diverse protein machinery composed of chaperone proteins and a variety of helpers, such as the co-chaperones, folding enzymes, and... (Review)
Review
The chaperome is a large and diverse protein machinery composed of chaperone proteins and a variety of helpers, such as the co-chaperones, folding enzymes, and scaffolding and adapter proteins. Heat shock protein 90s and 70s (HSP90s and HSP70s), the most abundant chaperome members in human cells, are also the most complex. As we have learned to appreciate, their functions are context dependent and manifested through a variety of conformations that each recruit a subset of co-chaperone, scaffolding, and folding proteins and which are further diversified by the posttranslational modifications each carry, making their study through classic genetic and biochemical techniques quite a challenge. Chemical biology tools and techniques have been developed over the years to help decipher the complexities of the HSPs and this review provides an overview of such efforts with focus on HSP90 and HSP70.
Topics: Animals; HSP70 Heat-Shock Proteins; HSP90 Heat-Shock Proteins; Humans; Models, Molecular; Molecular Diagnostic Techniques; Molecular Probe Techniques; Molecular Probes
PubMed: 26933742
DOI: 10.1016/j.chembiol.2015.12.006 -
ChemistryOpen Jul 2022Norepinephrine (NE), acting as both a neurotransmitter and hormone, plays a significant role in regulating the action of the brain and body. Many studies have...
Norepinephrine (NE), acting as both a neurotransmitter and hormone, plays a significant role in regulating the action of the brain and body. Many studies have demonstrated a strong correlation between mental disorders and aberrant NE levels. Therefore, it is of urgent demand to develop in vivo analytical methods of NE for diagnostic assessment and mechanistic investigations of mental diseases. Herein, we report a F MRI probe (NRFP) for sensing and imaging NE, which is constructed by conjugating a gadolinium chelate to a fluorine-containing moiety through a NE-responsive aromatic thiocarbonate linkage. The capacity and specificity of NRFP for detecting NE is validated with in vitro detecting/imaging experiments. Furthermore, the feasibility of NRFP for visualizing NE in animals is illustrated by ex vivo and in vivo imaging experiments, demonstrating the promising potential of NRFP for selective detection and specific imaging of NE in deep tissues of living subjects.
Topics: Animals; Contrast Media; Fluorine; Humans; Magnetic Resonance Imaging; Molecular Probes; Norepinephrine
PubMed: 35762743
DOI: 10.1002/open.202200110 -
Cancer Cell Jul 2017Small-molecule chemical probes or tools have become progressively more important in recent years as valuable reagents to investigate fundamental biological mechanisms... (Review)
Review
Small-molecule chemical probes or tools have become progressively more important in recent years as valuable reagents to investigate fundamental biological mechanisms and processes causing disease, including cancer. Chemical probes have also achieved greater prominence alongside complementary biological reagents for target validation in drug discovery. However, there is evidence of widespread continuing misuse and promulgation of poor-quality and insufficiently selective chemical probes, perpetuating a worrisome and misleading pollution of the scientific literature. We discuss current challenges with the selection and use of chemical probes, and suggest how biologists can and should be more discriminating in the probes they employ.
Topics: Humans; Molecular Probes; Neoplasms; Research Design
PubMed: 28697345
DOI: 10.1016/j.ccell.2017.06.005 -
Clinical Pharmacology and Therapeutics Nov 2018Drug transporters can govern the absorption, distribution, metabolism, and excretion of substrate drugs and endogenous substances. Investigations to examine their... (Review)
Review
Drug transporters can govern the absorption, distribution, metabolism, and excretion of substrate drugs and endogenous substances. Investigations to examine their potential impact to pharmacokinetic (PK) drug-drug interactions (DDIs) are an integral part of the risk assessment in drug development. To evaluate a new molecular entity as a potential perpetrator of transporters, use of well characterized and/or clinically relevant probe substrates with good selectivity and sensitivity are critical for robust clinical DDI assessment that could inform DDI management strategy in the product labeling. The availability of endogenous biomarkers to monitor transporter-mediated DDIs in early phases of clinical investigations would greatly benefit downstream clinical plans. This article reviews the state-of-the-art in transporter clinical probe drugs and emerging biomarkers, including current challenges and limitations, delineates methods and workflows to identify and validate novel endogenous biomarkers to support clinical DDI evaluations, and proposes how these probe drugs or biomarkers could be used in drug development.
Topics: Animals; Biomarkers; Drug Development; Drug Interactions; Humans; Membrane Transport Modulators; Membrane Transport Proteins; Models, Biological; Molecular Probe Techniques; Molecular Probes; Pharmacokinetics; Risk Assessment; Workflow
PubMed: 30347454
DOI: 10.1002/cpt.1216