Design and Synthesis of New Acridone-Based Nitric Oxide Fluorescent Probe.
Ontology highlight
ABSTRACT:
SUBMITTER: Panfilov M
PROVIDER: S-EPMC8307419 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:Nitric oxide (NO), a potent vasodilator and anti-atherogenic molecule, is synthesized in various cell types, including vascular endothelial cells (ECs). The biological importance of NO enforces the need to develop and characterize specific and sensitive probes. To date, several fluorophores, chromophores and colorimetric techniques have been developed to detect NO or its metabolites (NO(2) and NO(3)) in biological fluids, viable cells or cell lysates.Recently, a novel probe (NO(550)) has been developed and reported to detect NO in solutions and in primary astrocytes and neuronal cells with a fluorescence signal arising from a nonfluorescent background.Here, we report further characterization of this probe by optimizing conditions for the detection and imaging of NO products in primary vascular ECs, fibroblasts, and embryonic stem cell- and induced pluripotent stem cell-derived ECs in the absence and presence of pharmacological agents that modulate NO levels. In addition, we studied the stability of this probe in cells over time and evaluated its compartmentalization in reference to organelle-labeling dyes. Finally, we synthesized an inherently fluorescent diazo ring compound (AZO(550)) that is expected to form when the nonfluorescent NO(550) reacts with cellular NO, and compared its cellular distribution with that of NO(550).NO(550) is a promising agent for imaging NO at baseline and in response to pharmacological agents that modulate its levels.
| S-EPMC3927988 | biostudies-literature
Project description:In the present work, we systematically investigate the sensing abilities of two recently literature-reported two-photon fluorescent NO probes, i.e., the o-phenylenediamine derivative of Nile Red and the p-phenylenediamine derivative of coumarin. The recognition mechanisms of these probes are studied by using the molecular orbital classifying method, which demonstrates the photoinduced electron transfer process. In addition, we have designed two new probes by swapping receptor units present on fluorophores, i.e., the p-phenylenediamine derivative of Nile Red and the o-phenylenediamine derivative of coumarin. However, it illustrates that only the latter has ability to function as off-on typed fluorescent probe for NO. More importantly, calculations on the two-photon absorption properties of the probes demonstrate that both receptor derivatives of coumarin possess larger TPA cross-sections than Nile Red derivatives, which makes a better two photon fluorescent probe. Our theoretical investigations reveal that the underlying mechanism satisfactorily explain the experimental results, providing a theoretical basis on the structure-property relationships which is beneficial to developing new two-photon fluorescent probes for NO.
| S-EPMC5982152 | biostudies-literature
Project description:To study the role and (sub) cellular nitric oxide (NO) constitution in various disease processes, its direct and specific detection in living cells and tissues is a major requirement. Several methods are available to measure the oxidation products of NO, but the detection of NO itself has proved challenging. We visualized NO production using a NO-sensitive copper-based fluorescent probe (Cu 2FL2E) and two-photon laser scanning microscopy (TPLSM). Cu 2FL2E demonstrated high sensitivity and specificity for NO synthesis, combined with low cytotoxicity. Furthermore, Cu 2FL2E showed superior sensitivity over the conventionally used Griess assay. NO specificity of Cu 2FL2E was confirmed in vitro in human coronary arterial endothelial cells and porcine aortic endothelial cells using various triggers for NO production. Using TPLSM on ex vivo mounted murine carotid artery and aorta, the applicability of the probe to image NO production in both endothelial cells and smooth muscle cells was shown. NO-production and time course was detected for multiple stimuli such as flow, acetylcholine and hydrogen peroxide and its correlation with vasodilation was demonstrated. NO-specific fluorescence and vasodilation was abrogated in the presence of NO-synthesis blocker L-NAME. Finally, the influence of carotid precontraction and vasorelaxation validated the functional properties of vessels. Specific visualization of NO production in vessels with Cu 2FL2E-TPLSM provides a valid method for studying spatial-temporal synthesis of NO in vascular biology at an unprecedented level. This approach enables investigation of the pathways involved in the complex interplay between NO and vascular (dys) function.
| S-EPMC3781046 | biostudies-literature
Project description:Fluorescence assays employing semisynthetic or commercial dansyl-polymyxin B have been widely employed to assess the affinity of polycations, including polymyxins, for bacterial cells and lipopolysaccharide (LPS). The five primary ?-amines on diaminobutyric acid residues of polymyxin B are potentially derivatized with dansyl-chloride. Mass spectrometric analysis of the commercial product revealed a complex mixture of di- or tetra-dansyl-substituted polymyxin B. We synthesized a mono-substituted fluorescent derivative, dansyl[Lys]¹polymyxin B?. The affinity of polymyxin for purified gram-negative LPS and whole bacterial cells was investigated. The affinity of dansyl[Lys]¹polymyxin B? for LPS was comparable to polymyxin B and colistin, and considerably greater (K(d)<1 ?M) than for whole cells (K(d)?6-12?M). Isothermal titration calorimetric studies demonstrated exothermic enthalpically driven binding between both polymyxin B and dansyl[Lys]¹polymyxin B? to LPS, attributed to electrostatic interactions. The hydrophobic dansyl moiety imparted a greater entropic contribution to the dansyl[Lys]¹polymyxin B?-LPS reaction. Molecular modeling revealed a loss of electrostatic contact within the dansyl[Lys]¹polymyxin B?-LPS complex due to steric hindrance from the dansyl[Lys]¹ fluorophore; this corresponded with diminished antibacterial activity (MIC?16?g/mL). Dansyl[Lys]¹polymyxin B? may prove useful as a screening tool for drug development.
| S-EPMC3106281 | biostudies-literature
Project description:Nitric oxide (NO) is often involved in many different physiological processes including the regulation of lysosomal functions. However, it remains a great challenge to explore the variations of NO levels in lysosomes, limiting the understanding behind its biological functions in cellular signaling pathways and various diseases. Herein, a pH-activatable fluorescent probe, Rhod-H-NO, was designed and synthesized for the determination of lysosomal NO, in which the activation response model is beneficial towards getting accurate biological information. To ensure that Rhod-H-NO can accumulate effectively and exist stably in lysosomes without interference and degradation from other active species, Rhod-H-NO was engineered into the nanopores of mesoporous silica nanoparticles (MSNs) with ?-cyclodextrin (?-CD) as the gatekeeper to obtain a nanolab. The nanolab was successfully applied to detect lysosomal NO in living cells and in vivo with high time and spatial resolution. This nanolab could serve as an excellent molecular tool to exploit and elucidate the function of NO at sub-cellular levels.
| S-EPMC5966799 | biostudies-other
Project description:Once it was discovered that the enzyme nitric oxide synthase (NOS) is responsible for the biosynthesis of NO, NOS became a drug target. Particularly important is the over production of NO by neuronal NOS (nNOS) in various neurodegenerative disorders. After the various NOS isoforms were identified, inhibitor development proceeded rapidly. It soon became evident, however, that isoform selectivity presents a major challenge. All 3 human NOS isoforms, nNOS, eNOS (endothelial NOS), and iNOS (inducible NOS) have nearly identical active site structures thus making selective inhibitor design especially difficult. Of particular importance is the avoidance of inhibiting eNOS owing to its vital role in the cardiovascular system. This review summarizes some of the history of NOS inhibitor development and more recent advances in developing isoform selective inhibitors using primarily structure-based approaches.
| S-EPMC5569579 | biostudies-literature
Project description:Fluorescent turn-on probes for nitric oxide based on seminaphthofluorescein scaffolds were prepared and spectroscopically characterized. The Cu(II) complexes of these fluorescent probes react with NO under anaerobic conditions to yield a 20-45-fold increase in integrated emission. The seminaphthofluorescein-based probes emit at longer wavelengths than the parent FL1 and FL2 fluorescein-based generations of NO probes, maintaining emission maxima between 550 and 625 nm. The emission profiles depend on the excitation wavelength; maximum fluorescence turn-on is achieved at excitations between 535 and 575 nm. The probes are highly selective for NO over other biologically relevant reactive nitrogen and oxygen species including NO(3)(-), NO(2)(-), HNO, ONOO(-), NO(2), OCl(-), and H(2)O(2). The seminaphthofluorescein-based probes can be used to visualize endogenously produced NO in live cells, as demonstrated using Raw 264.7 macrophages.
| S-EPMC3183332 | biostudies-literature
Project description:Copper, as the third most abundant transition metal ions of human, plays an essential role in the redox reaction, signal transduction, hematopoiesis, and other physiological processes. Abnormal content of copper ions in the body will cause some diseases such as anemia, coronary heart disease, Menkes' syndrome. In this article, a new fluorescence probe L for Cu2+ was designed and synthetized by using 4-bromo-1,8 naphthalene anhydride and 2-thiophene formaldehyde as raw materials. Fluorescent probe L itself exhibited strong fluorescence, upon the addition of Cu2+ ions, the fluorescence was quenched. The fluorescent detection limit for Cu2+ ions was determined to be 1.8 ?M based on a 3?/S method. UV-vis absorption and fluorescence spectra indicated that probe L showed good selectivity and sensitivity for Cu2+, and this selectivity was not interfered by other metal ions and anions. Further cell fluorescence imaging experiments indicated that the probe L had potential to be used to examine copper ions in vivo.
| S-EPMC5658116 | biostudies-literature
Project description:rs05-08_no - no - Cadmium treatment induces slow but long lasting nitric oxide production in plant tissues. This NO production can be suppressed using the commonly used Nitric Oxide Synthase inhibitor L-NAME. This inhibitor tends to partially alleviate Cd toxicity. This effect is correlated with a strong diminution of Cd content in roots of plants treated both with Cd and L-NAME compared to roots from plants treated with Cd only. The main goal of this study is the identification of transcriptionnal changes caused by Cd-induced nitric oxide, and that could potentially result in enhanced Cd root accumulation. - Germination of surface sterilized seeds was performed on solid MS/2 medium. After 2 weeks, the young plantlets were placed on sand for an additional 3 week period in a controlled environment (8 h photoperiod of 300 umol m-2 s-1, 22degreeC, 70% relative humidity) . Plants of similar rosette diameters were then transfered to an hydroponic culture using the nutritive solution described in [Gravot et al. 2004 FEBS Letters 561:22-28] for an acclimation of 3 days. L-NAME and cadmium treatments were respectively started 1 and 2 hours after the start of illumination and root tissues were collected 24 h later and immediatly frozen in liquid nitrogen before RNA extraction. Treatments were : 1 : control 2 : L-NAME 5 mM 3 : Cd 30 uM 4 : L-NAME 5mM + Cd 30 uM 5 : Cd 15 uM For each condition, 3 independent biological repetitions were conducted. RNA were extracted separatly and checked for quality before pooling together. Keywords: treated vs untreated comparison
2007-05-31 | GSE7945 | GEO
Project description:In situ fluorescence imaging of nitric oxide (NO) is a powerful tool for studying the critical roles of NO in biological events. However, the selective imaging of NO is still a challenge because most currently available fluorescent probes rely on the o-phenylenediamine (OPD) recognition site, which reacts with both NO and some abundant reactive carbonyl species (RCS) (such as dehydroascorbic acid and methylglyoxal) and some reactive oxygen/nitrogen species (ROS/RNS). To address this problem, a new fluorescent probe, NCNO, based on the N-nitrosation of aromatic secondary amine was designed to bypass the RCS, ROS, and RNS interference. As was expected, the probe NCNO could recognize NO with pronounced selectivity and sensitivity among ROS, RNS, and RCS. The probe was validated by detecting NO in live cells and deep tissues owing to its two-photon excitation and red-light emission. It was, hence, applied to monitor NO in ischemia reperfusion injury (IRI) in mice kidneys by two-photon microscopy for the first time, and the results vividly revealed the profile of NO generation in situ during the renal IRI process.
| S-EPMC5472031 | biostudies-literature