•In vivo fluorescence imaging is important for disease diagnosis and evaluation.•Strategies for developing fluorescent probes using cyanine dyes are summarized.•Cyanine-based probes and materials ...provide appropriate tools for biomedical visualization.
In vivo fluorescence imaging provides vital information required for biomedical research in living animals, and as such plays an essential role in disease assessment. Unfortunately, due to the lack of coherent approaches, in vivo fluorescence visualization is challenging, wasting not only time but the animals used. In recent years, cyanine-based systems have been found to exhibit attractive optical properties with appropriate bio-functionality and therefore have become go-to probes for in vivo research. Herein, we collected the recent breakthroughs using cyanine-based systems associated with use in living mammals, to provide researchers with the required information to develop appropriate strategies able to meet the increasing stringent requirements for practical applications. We concentrate on 6 sites within the cyanine skeleton, including the: meso-position (1), N-indole (2), phenyl-indole (2), cyclohexane (1), which have been used to design symmetric or asymmetric cyanine structures. Substitutions at the meso-position provide fluorescence probes featuring a switch of EWG and EDG, PET, spiro-cyclization, ICT within the cyanine skeleton, or FRET, for visualizing analytes in vivo. Substitution at the N-indole forms a positively charged system with long wavelength emission suitable for in vivo imaging. While, modification of the phenyl-indole contributes to the functional properties, including photoacoustic, photothermal and photodynamic behavior, which can be used for multimodal imaging as well as functional imaging in vivo. With a specific trigger at the N-indole or meso-position, NIR fluorescence pro-drugs could be developed for in vivo tracing of the efficiency of drug delivery. While modification of the cyclohexane can introduce a targeting moiety for the accurate monitoring of tumors or organs. Using these strategies appropriate design platforms can be developed to provide the next generation of optical systems for living animal research. Moreover, we hope this review will enable researchers to design systems with high efficiency for in vivo research, which will reduce both the development time and number of animals required to progress the research.
The malondialdehyde (MDA)-specific detection probe (MDA-6) was successfully synthesised through the photoinduced electron transfer (PET) mechanism which possesses many biological applications. ...In vivo biological applicability of this probe was proved in different cell lines, zebrafish and mice. In these models, the MDA was produced by oxygen stress injury and the relationship between MDA and probe were evaluated in vitro as well as in vivo under different stress conditions. After comparing evaluated results with commercial MDA kit, MDA-6 was concluded with high specificity, low limit of detection (0.03 μM), and can achieve micro-detection of MDA with low cytotoxicity, demonstrating MDA-6 enables safe and effective detection.
When MDA-6 entered into the body and combined with MDA, the fluorescence signal can be produced with low limit of detection (0.03 μM). These produced signals of MDA-6 can detect MDA in cells, zebrafish, and mice sensitively without the use of cumbersome conventional kits.Chemical structure of MDA-6 and application in different models. Display omitted
•The synthesis of probe (MDA-6) used photoinduced electron transfer mechanism with low detection limit and high specificity.•The MDA-6 was successfully achieved detecting and fluorescent visualizing endogenous MDA in cells, living zebrafish and mice•The fluorescence of MDA-6-MDA is stable in the pH range of 6–8 and proper to physiological range.
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It is essential to optimize a carrier of dry powder inhalation (DPI) for the aerodynamic deposition in vitro to achieve pulmonary delivery of drug molecules in vivo. In this study, ...neutralized nanoporous γ-cyclodextrin metal-organic framework (CD-MOF) crystals with cubic morphology and uniform inhalation size were developed and modified as a DPI carrier for budesonide (BUD). Cholesterol (CHO) and leucine (LEU)-poloxamer were used to modify the CD-MOF powder for the improvement of flowability and particle aerodynamic behaviour, for which the particle size distribution, Carr's index and in vitro pulmonary deposition were assessed. Compared to CD-MOF or LEU-CD-MOF-BUD, CHO-CD-MOF had a superior mass median aerodynamic diameter (4.35 ± 0.04 μm) and inhalable performance (fine particle fraction of 30.60 ± 0.76%), which were maintained after budesonide loading (4.47 ± 0.30 μm, 24.95 ± 4.33%). The crystallinity, cytotoxicity and in vivo deposition of drug loaded samples (CHO-CD-MOF-BUD) were then investigated by powder X-ray diffraction (PXRD), cell viability study, in vivo fluorescence imaging and pharmacokinetic studies in rats. The characteristic PXRD crystallinity peaks of budesonide disappeared after being loaded into CHO-CD-MOF, potentially indicating the molecular incorporation of budesonide into the pores of CD-MOF. The cell viability of A549 cell was more than 90% for CHO-CD-MOF-BUD as a result of the good biocompatibility of CD-MOF. When Rhodamine B was carried by the DPI particles, the fluorescence signal at the lung tissue was markedly improved after cholesterol modification compared with CD-MOF, whilst the bioavailability of CHO-CD-MOF-BUD in rat was equivalent with that of the commercial product of Pulmicort Turbuhaler. Therefore, the CD-MOF powders modified by cholesterol can be used as a promising inhalable carrier for pulmonary delivery of drugs with small dose.
Abstract The purpose of this study is to demonstrate scarless vocal fold (VF) regeneration by using a composite gel composed of small intestine submucosa (SIS) and mesenchymal stem cells (MSCs). A ...scar was made with an electrocoagulator on both VFs in 24 rabbits, followed by injection of either MSCs, SIS, or MSCs-SIS composite gel in the right side VF, while the left side VF was left untreated. VF scars were evaluated with in vivo fluorescence live imaging system (IFLIS), endoscopy, histology, and videokymography (VKG) after eight weeks. IFLIS demonstrated that SIS enabled the MSCs to survive and be engrafted in the VF. The histological analysis showed increased hyaluronic acid accumulation and controlled collagen deposition by MSCs-SIS composite gel. VKG analysis showed more favorable vibrations of MSCs-SIS injected VF, compared to other treatment group. In conclusion, the injectable SIS supplied a niche for the MSCs to stably settle down in scarred VFs and helped to regulate ECM synthesis. The ECM remodeling underwent by the surviving MSCs eventually led to the functional improvement of the VF. The results of the present investigation suggest that SIS-MSCs composite gel is a plausible biomaterial for prolonged survival of MSCs in VFs and promotes scarless VF healing.
Intravital imaging of brain vasculature through the intact cranium in vivo is based on the evolution of the fluorescence intensity and provides an ability to characterize various physiological ...processes in the natural context of cellular resolution. The involuntary motions of the examined subjects often limit in vivo non-invasive functional optical imaging. Conventional imaging diagnostic modalities encounter serious difficulties in correction of artificial motions, associated with fast high dynamics of the intensity values in the collected image sequences, when a common reference cannot be provided. In the current report, we introduce an alternative solution based on a time-space Fourier transform method so-called K-Omega. We demonstrate that the proposed approach is effective for image stabilization of fast dynamic image sequences and can be used autonomously without supervision and assignation of a reference image.
Chymotrypsin is a medication that is useful in treating inflammation, edema, expectoration, and corruption. It has a wide range of medical applications. Therefore, it is critical to create a ...chymotrypsin real-time drug tracking detection approach. The ester bond in the molecule can be severed by chymotrypsin. Intramolecular charge transfer (ICT) recovers when the ester bond in the probe breaks, resulting in fluorescence. As a result, in this research, we built and investigated the "turn-on" fluorescent probe NBD-1, NBD-2, and NBD-3, which are used to detect endogenous chymotrypsin, and explored the effect of molecular chain length on probe sensitivity through density functional theory (DFT) calculation and spectral testing, and screened the best probe NBD-3, which is a rare bright red fluorescence probe. The presence of endogenous chymotrypsin was subsequently discovered for the first time in the liver of mice with NBD-3 probe in confocal imaging of HeLa cells, in vivo imaging of mice, and in vitro imaging of organs in the experiment. This result confirmed that such probes could precisely detect the distribution of chymotrypsin in various organs of the organism. NBD-3's strong performance makes it possible to detect chymotrypsin medications in real time with a robust tool.
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•Three probes(NBD-1, NBD-2, NBD-3) were synthesized.•The probe NBD-3 has best sensitivity of chymotrypsin.•Probe NBD-3 detected the activity of chymotrypsin in HeLa cells and mice.•For the first time, chymotrypsin was detected in mouse liver using probe NBD-3.
FRET as the tool for in vivo nanomedicine tracking Kaeokhamloed, Norraseth; Legeay, Samuel; Roger, Emilie
Journal of controlled release,
September 2022, 2022-09-00, 20220901, 2022-09, Volume:
349
Journal Article
Peer reviewed
Open access
Advanced drug delivery system utilizing a nanocarrier is the major application of nanotechnology on pharmacotherapeutics. However, despite the promising benefits and a leading trend in pharmaceutical ...research, nanomedicine development suffers from a poor clinical translation problem as only a handful of nanomedicine products reach the market yearly. The conventional pharmacokinetic study generally focuses only on monitoring the level of a free drug but ignores the nanocarrier's role in pharmacokinetics. One hurdle is that it is difficult to directly track intact nanocarriers in vivo to explore their pharmacokinetics. Although several imaging techniques such as radiolabeling, nuclear imaging, fluorescence imaging, etc., have been developed over the past few years, currently, one method that can successfully track the intact nanocarriers in vivo directly is by Förster resonance energy transfer (FRET). This review summarizes the application of FRET as the in vivo nanoparticle tracker for studying the in vivo pharmacokinetics of the organic nanocarriers and gives elaborative details on the techniques utilized.
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•FRET directly tracks intact organic nanoparticles in vivo semi-quantitatively.•FRET allows for live imaging biodistribution study of intact nanoparticles.•FRET spectra can be analyzed by conventional fluorometer or confocal microscopy.
Far-red emitting fluorescent labels are highly desirable for spectral multiplexing and deep tissue imaging. Here, we describe the generation of frFAST (far-red Fluorescence Activating and absorption ...Shifting Tag), a 14-kDa monomeric protein that forms a bright far-red fluorescent assembly with (4-hydroxy-3-methoxy-phenyl)allylidene rhodanine (HPAR-3OM). As HPAR-3OM is essentially nonfluorescent in solution and in cells, frFAST can be imaged with high contrast in presence of free HPAR-3OM, which allowed the rapid and efficient imaging of frFAST fusions in live cells, zebrafish embryo/larvae and chicken embryo. Beyond enabling genetic encoding of far-red fluorescence, frFAST allowed the design of a farred chemogenetic reporter of protein-protein interactions, demonstrating its great potential for the design of innovative far-red emitting biosensors.
Here we report the synthesis of PLGA/DOXO-core Au-branched shell nanostructures (BGNSHs) functionalized with a human serum albumin/indocyanine green/folic acid complex (HSA-ICG-FA) to configure a ...multifunctional nanotheranostic platform. First, branched gold nanoshells (BGNSHs) were obtained through a seeded-growth surfactant-less method. These BGNSHs were loaded during the synthetic process with the chemotherapeutic drug doxorubicin, a DNA intercalating agent and topoisomerase II inhibitior. In parallel, the fluorescent near-infrared (NIR) dye indocyanine green (ICG) was conjugated to the protein human serum albumin (HSA) by electrostatic and hydrophobic interactions. Subsequently, folic acid was covalently attached to the HSA-ICG complex. In this way, we created a protein complex with targeting specificity and fluorescent imaging capability. The resulting HSA-ICG-FA complex was adsorbed to the gold nanostructures surface (BGNSH-HSA-ICG-FA) in a straightforward incubation process thanks to the high affinity of HSA to gold surface. In this manner, BGNSH-HSA-ICG-FA platforms were featured with multifunctional abilities: the possibility of fluorescence imaging for diagnosis and therapy monitoring by exploiting the inherent fluorescence of the dye, and a multimodal therapy approach consisting of the simultaneous combination of chemotherapy, provided by the loaded drug, and the potential cytotoxic effect of photodynamic and photothermal therapies provided by the dye and the gold nanolayer of the hybrid structure, respectively, upon NIR light irradiation of suitable wavelength. The combination of this trimodal approach was observed to exert a synergistic effect on the cytotoxicity of tumoral cells in vitro. Furthermore, FA was proved to enhance the internalization of nanoplatform. The ability of the nanoplatforms as fluorescence imaging contrast agents was tested by preliminary analyzing their biodistribution in vivo in a tumor-bearing mice model.
Endogenous circadian clocks control 24-h physiological and behavioral rhythms in mammals. Here, we report a real-time in vivo fluorescence recording system that enables long-term monitoring of ...circadian rhythms in the brains of freely moving mice. With a designed reporter of circadian clock gene expression, we tracked robust Cry1 transcription reporter rhythms in the suprachiasmatic nucleus (SCN) of WT, Cry1
−/−, and Cry2
−/− mice in LD (12 h light, 12 h dark) and DD (constant darkness) conditions and verified that signals remained stable for over 6 mo. Further, we recorded Cry1 transcriptional rhythms in the subparaventricular zone (SPZ) and hippocampal CA1/2 regions of WT mice housed under LD and DD conditions. By using a Cre-loxP system, we recorded Per2 and Cry1 transcription rhythms specifically in vasoactive intestinal peptide (VIP) neurons of the SCN. Finally, we demonstrated the dynamics of Per2 and Cry1 transcriptional rhythms in SCN VIP neurons following an 8-h phase advance in the light/dark cycle.
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