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International Journal of Molecular... Jan 2022Fluorescein is a fluorescent dye used as a diagnostic tool in various fields of medicine. Although fluorescein itself possesses low toxicity, after photoactivation, it...
Fluorescein is a fluorescent dye used as a diagnostic tool in various fields of medicine. Although fluorescein itself possesses low toxicity, after photoactivation, it releases potentially toxic molecules, such as singlet oxygen (O) and, as we demonstrate in this work, also carbon monoxide (CO). As both of these molecules can affect physiological processes, the main aim of this study was to explore the potential biological impacts of fluorescein photochemistry. In our in vitro study in a human hepatoblastoma HepG2 cell line, we explored the possible effects on cell viability, cellular energy metabolism, and the cell cycle. We observed markedly lowered cell viability (≈30%, 75-2400 μM) upon irradiation of intracellular fluorescein and proved that this decrease in viability was dependent on the cellular oxygen concentration. We also detected a significantly decreased concentration of Krebs cycle metabolites (lactate and citrate < 30%; 2-hydroxyglutarate and 2-oxoglutarate < 10%) as well as cell cycle arrest (decrease in the G2 phase of 18%). These observations suggest that this photochemical reaction could have important biological consequences and may account for some adverse reactions observed in fluorescein-treated patients. Additionally, the biological activities of both O and CO might have considerable therapeutic potential, particularly in the treatment of cancer.
Topics: Angiography; Antineoplastic Agents; Carbon Monoxide; Cell Cycle Checkpoints; Cell Survival; Citric Acid Cycle; Fluorescein; Gas Chromatography-Mass Spectrometry; Hep G2 Cells; Humans; Light; Photochemical Processes; Singlet Oxygen
PubMed: 35163426
DOI: 10.3390/ijms23031504 -
Indian Journal of Ophthalmology Apr 2023The health of the ocular surface is vital for clear vision and comfort. Various factors can adversely influence the ocular surface and tear film homeostasis, and these... (Review)
Review
The health of the ocular surface is vital for clear vision and comfort. Various factors can adversely influence the ocular surface and tear film homeostasis, and these include procedures like cataract and corneal refractive surgery. It is, therefore, important to assess the integrity of the ocular surface in a rapid, predictable, and consistent manner in the clinic. Various tests and devices have been described, and while these are useful, this article highlights the importance of using fluorescein staining of the ocular surface in detecting changes. This is a simple, inexpensive, rapidly performed test that is available in most eye clinics. However, a proper technique of dye instillation and assessment is important to recognize the changes that can occur. Once detected, these changes can be quantified, and the location and patterns can be used to diagnose the diseases that are present; these changes can also be used to monitor treatment outcomes and disease progression. The article discusses the technique, assessment, and interpretation of fluorescein staining of the ocular surface, along with the role of the two other vital dyes - rose bengal and lissamine green.
Topics: Humans; Dry Eye Syndromes; Lissamine Green Dyes; Staining and Labeling; Fluorescein; Cornea; Tears
PubMed: 37026238
DOI: 10.4103/ijo.IJO_2137_22 -
Biochemistry Nov 2021The measurement of ion concentrations and fluxes inside living cells is key to understanding cellular physiology. Fluorescent indicators that can infiltrate and provide...
The measurement of ion concentrations and fluxes inside living cells is key to understanding cellular physiology. Fluorescent indicators that can infiltrate and provide intel on the cellular environment are critical tools for biological research. Developing these molecular informants began with the seminal work of Racker and colleagues ( (1979) 18, 2210), who demonstrated the passive loading of fluorescein in living cells to measure changes in intracellular pH. This work continues, employing a mix of old and new tradecraft to create innovative agents for monitoring ions inside living systems.
Topics: Biochemistry; Fluorescein; Fluorescent Dyes; History, 20th Century; Hydrogen-Ion Concentration; Intravital Microscopy; Microscopy, Fluorescence
PubMed: 34096721
DOI: 10.1021/acs.biochem.1c00299 -
Tomography (Ann Arbor, Mich.) Aug 2023Recent advances in tumor visualization have improved the extent of resection (EOR) of primary and secondary tumors of the central nervous system, while limiting the... (Meta-Analysis)
Meta-Analysis Review
Intraoperative Fluorophores: An Update on 5-Aminolevulinic Acid and Sodium Fluorescein in Resection of Tumors of the Central Nervous System and Metastatic Lesions-A Systematic Review and Meta-Analysis.
INTRODUCTION
Recent advances in tumor visualization have improved the extent of resection (EOR) of primary and secondary tumors of the central nervous system, while limiting the morbidity and mortality of the surgery. One area of recent interest has been the use of intraoperative fluorophores for tumor visualization such as 5-aminolevulinic acid (5-ala) and sodium fluorescein. We performed a systematic review and meta-analysis on the utility of fluorophore administration and EOR with each fluorophore to update the current literature.
METHODS
We conducted a systematic review and meta-analysis on the use of intraoperative 5-ala or fluorescein between 2021 and 2023 using the PubMed, SCOPUS, and WOS databases. The initial search yielded 8688 results. After inclusion and exclusion criteria were met, 44 studies remained for review. A meta-analysis was performed to compare the EOR between studies for each fluorophore and to compare the presence of intraoperative fluorescence by tumor type. Odds ratios (OR) were calculated for gross total resection (GTR), and two-way ANOVA tests were performed to compare rates of intraoperative fluorescence by fluorophore and tumor type.
RESULTS
In all groups except low-grade glioma, fluorescence was present after 5-ala administration; fluorescence was present for all groups after fluorescein administration. Two-way ANOVA analysis for both fluorophores demonstrated no statistically significant difference in presence of fluorescence between type of tumor resected. Meta-analysis of EOR did show a higher, but not significant, rate of GTR in the 5-ala group compared to controls (OR = 1.29, 95% CI = 0.49; 3.37). In the fluorescein group, there were statistically significant higher odds of GTR compared to the control group (OR = 2.10, 95% CI = 1.43; 3.10, I = 0%).
CONCLUSIONS
Both 5-ala and sodium fluorescein demonstrated intraoperative fluorescence among various tumor types in both cranial and spinal tumors, as well as efficacy in improving EOR. Both fluorophores merit further investigation for use in surgery of CNS tumors.
Topics: Humans; Fluorescein; Aminolevulinic Acid; Levulinic Acids; Glioma
PubMed: 37736977
DOI: 10.3390/tomography9050124 -
Journal of the American Chemical Society Apr 2021Xanthene fluorophores, like fluorescein, have been versatile molecules across diverse fields of chemistry and life sciences. Despite the ubiquity of 3-carboxy and...
Xanthene fluorophores, like fluorescein, have been versatile molecules across diverse fields of chemistry and life sciences. Despite the ubiquity of 3-carboxy and 3-sulfonofluorescein for the last 150 years, to date, no reports of 3-phosphonofluorescein exist. Here, we report the synthesis, spectroscopic characterization, and applications of 3-phosphonofluoresceins. The absorption and emission of 3-phosphonofluoresceins remain relatively unaltered from the parent 3-carboxyfluorescein. 3-Phosphonofluoresceins show enhanced water solubility compared to 3-carboxyfluorescein and persist in an open, visible light-absorbing state even at low pH and in low dielectric media while 3-carboxyfluoresceins tend to lactonize. In contrast, the spirocyclization tendency of 3-phosphonofluoresceins can be modulated by esterification of the phosphonic acid. The bis-acetoxymethyl ester of 3-phosphonofluorescein readily enters living cells, showing excellent accumulation (>6x) and retention (>11x), resulting in a nearly 70-fold improvement in cellular brightness compared to 3-carboxyfluorescein. In a complementary fashion, the free acid form of 3-phosphonofluorescein does not cross cellular membranes, making it ideally suited for incorporation into a voltage-sensing scaffold. We develop a new synthetic route to functionalized 3-phosphonofluoresceins to enable the synthesis of phosphono-voltage sensitive fluorophores, or phosVF2.1.Cl. Phosphono-VF2.1.Cl shows excellent membrane localization, cellular brightness, and voltage sensitivity (26% ΔF/F per 100 mV), rivaling that of sulfono-based VF dyes. In summary, we develop the first synthesis of 3-phosphonofluoresceins, characterize the spectroscopic properties of this new class of xanthene dyes, and utilize these insights to show the utility of 3-phosphonofluoresceins in intracellular imaging and membrane potential sensing.
Topics: Cell Membrane; Cell Membrane Permeability; Cyclization; Fluorescein; Fluoresceins; HEK293 Cells; Humans; Hydrogen-Ion Concentration; Spectrometry, Fluorescence
PubMed: 33797899
DOI: 10.1021/jacs.1c01139 -
Scientific Reports Jun 2021This study aims to investigate the reliability and efficacy of maximum fluorescein tear break-up time (FTBUTmax) in diagnosing dry eye disease (DED). 147 participants... (Randomized Controlled Trial)
Randomized Controlled Trial
This study aims to investigate the reliability and efficacy of maximum fluorescein tear break-up time (FTBUTmax) in diagnosing dry eye disease (DED). 147 participants were enrolled in this study. Ocular symptoms were assessed by Ocular Surface Disease Index (OSDI). The fluorescein tear break-up time (FTBUT) examination, corneal fluorescein staining (CFS), and Schirmer I test were performed on both eyes. Each participant underwent 3 consecutive FTBUT tests, and five types of FTBUT values including FTBUTmax, the minimum FTBUT (FTBUTmin), the first FTBUT (FTBUT1), the average of three FTBUTs (FTBUT123) and the average of the first and second FTBUT (FTBUT12) were recorded. FTBUTmax was larger than the other FTBUT values, but no differences were found among the values of FTBUT1, FTBUT123, FTBUT12 and FTBUTmin. In the ROC analysis, FTBUTmax had the largest or the second largest area under the ROC (AUROC) in all three DED diagnostic criteria, while FTBUTmin had the least AUROC of them. ROC efficacy of FTBUTmax was significantly higher than that of FTBUT123, FTBUT12, FTBUT1 and FTBUTmin in the OSDI criteria and higher than that of FTBUT1 and FTBUTmin in Schirmer I test and CFS tests. FTBUTmax has a close correlation with OSDI, Schirmer I test and CFS, and is an effective tool for the DED diagnosis.
Topics: Adult; Dry Eye Syndromes; Female; Fluorescein; Humans; Male; Middle Aged; Prospective Studies; Tears
PubMed: 34075199
DOI: 10.1038/s41598-021-91110-9 -
American Journal of Physiology.... Aug 2022Quantitative measurement of the degree of hepatic ischemia-reperfusion injury (IRI) is crucial for developing therapeutic strategies for its treatment. We hypothesized...
Quantitative measurement of the degree of hepatic ischemia-reperfusion injury (IRI) is crucial for developing therapeutic strategies for its treatment. We hypothesized that clearance of fluorescent dye through bile metabolism may reflect the degree of hepatic IRI. In this study, we investigated sodium fluorescein clearance kinetics in blood and bile for quantifying the degree of hepatic IRI. Warm ischemia times (WITs) of 0, 30, or 60 min followed by 1 h or 4 h of reperfusion, were applied to the median and lateral lobes of the liver in Sprague-Dawley rats. Subsequently, 2 mg/kg of sodium fluorescein was injected intravenously, and blood and bile samples were collected over 60 min to measure fluorescence intensities. The bile-to-plasma fluorescence ratios demonstrated an inverse correlation with WIT and were distinctly lower in the 60-min WIT group than in the control or 30-min WIT groups. Bile-to-plasma fluorescence ratios displayed superior discriminability for short versus long WITs when measured 1 h after reperfusion versus 4 h. We conclude that the bile-to-blood ratio of fluorescence after sodium fluorescein injection has the potential to enable the quantification of hepatic IRI severity. Previous attempts to use fluorophore clearance to test liver function have relied on a single source of data. However, the kinetics of substrate processing via bile metabolism include decreasing levels in blood and increasing levels in bile. Thus, we analyzed data from blood and bile to better reflect fluorescein clearance kinetics.
Topics: Animals; Bile; Fluorescein; Kinetics; Liver; Rats; Rats, Sprague-Dawley; Reperfusion Injury
PubMed: 35700191
DOI: 10.1152/ajpgi.00038.2022 -
Translational Vision Science &... Aug 2020To conduct aqueous angiography (AA) using a clinically applicable technique in normal dogs and to compare findings to intravenous scleral angiography (SA).
PURPOSE
To conduct aqueous angiography (AA) using a clinically applicable technique in normal dogs and to compare findings to intravenous scleral angiography (SA).
METHODS
We examined 10 canine cadaver eyes and 12 eyes from live normal dogs. A gravity-fed trocar system delivered 2% sodium fluorescein and 0.25% indocyanine green (ICG) intracamerally (IC) in cadaver eyes. In vivo AA was subsequently performed in one eye of each of the 12 dogs via IC bolus of ICG under sedation. The same 12 dogs received SA via intravenous ICG (mean ± SD) 10.7 ± 3.3 days later. Identical scleral sectors were imaged using a Spectralis confocal scanning laser ophthalmoscope.
RESULTS
The gravity-fed trocar system permitted visualization of the conventional aqueous humor outflow (CAHO) pathways in cadaver eyes, but not in vivo. Fluorescence was observed superonasally in four of the 10 cadaver eyes within 24.0 ± 3.6 seconds. A single IC bolus of ICG showed CAHO pathways in vivo, demonstrating sectoral outflow patterns in the superotemporal sclera in 10 of the 12 eyes within 35.0 ± 4.3 seconds; four of the 12 eyes exhibited pulsatile aqueous movement. SA exhibited fluorescence patterns comparable to AA with weak pulsatile aqueous humor outflow.
CONCLUSIONS
Angiography (AA or SA) in dogs permits visualization of the CAHO pathway and its vascular components in vivo. AA may be a more useful modality to assess aqueous humor outflow.
TRANSLATIONAL RELEVANCE
Intracameral AA has potential utility for evaluating CAHO in vivo in dogs, an important animal model species
Topics: Animals; Aqueous Humor; Dogs; Fluorescein; Fluorescein Angiography; Indocyanine Green; Sclera
PubMed: 32934894
DOI: 10.1167/tvst.9.9.44 -
Molecules (Basel, Switzerland) Jan 2018In this study, three new fluorescein derivatives-5-bromo-4',5'-dinitrofluorescein (), 5-bromo-4',5'-diaminofluorescein (), and...
In this study, three new fluorescein derivatives-5-bromo-4',5'-dinitrofluorescein (), 5-bromo-4',5'-diaminofluorescein (), and 5-bromo-4',5'-bis(dimethylamino)fluorescein ()-were synthesized and their pH-dependent protolytic equilibria were investigated. In particular, exhibited pH-dependent fluorescence, showing strong emission only at pH 3-6. bears a bromine moiety and thus, can be used in various cross-coupling reactions to prepare derivatives and take advantage of its unique emission properties. To confirm this, the Suzuki and Sonogashira reactions of with phenylboronic acid and phenylacetylene, respectively, were performed, and the desired products were successfully obtained.
Topics: Acetylene; Boronic Acids; Fluorescein; Fluorescent Dyes; Hydrogen-Ion Concentration; Molecular Structure; Spectrometry, Fluorescence
PubMed: 29361711
DOI: 10.3390/molecules23010219 -
Contact Lens & Anterior Eye : the... Oct 2022To investigate the immediate short-term effects of smoking in habitual smokers, on the tear film, pupil size and accommodative ability of the human eye.
PURPOSE
To investigate the immediate short-term effects of smoking in habitual smokers, on the tear film, pupil size and accommodative ability of the human eye.
METHODS
Habitual smokers were tested within 5 min of smoking a cigarette. The tear film analysis was undertaken using tear break-up time (TBUT), tear lipid layer thickness and tears meniscus height (TMH) measurements. Three different ways of tear break-up time (TBUT) were used; using fluorescein; a non-invasive TBUT using tearscope; and a video captured method with a corneal topographer. Pupil size was measured objectively using the video capture on the corneal topographer. Accommodative ability was checked by performing a 'push up test' to measure amplitudes of accommodation (AoA) and by measuring defocus curves.
RESULTS
Forty-five participants were enrolled (mean age 22.0 ± 4.4 years). TBUT was reduced after smoking a cigarette with all three assessment methods and this reduction was statistically significant (p < 0.001). A reduction in lipid layer thickness was seen after smoking a cigarette with both methods used and was statistically significant (p < 0.01). A significant reduction in pupil size (p < 0.01) and in AoA (p < 0.001) was observed after smoking a cigarette. The difference in TMH and defocus curves, before and after smoking, were not statistically significant (p > 0.05).
CONCLUSION
The study shows that there is an immediate adverse effect of smoking on TBUT and AoA which seems to be very transient.
Topics: Adolescent; Adult; Dry Eye Syndromes; Fluorescein; Humans; Lipids; Smoking; Tears; Young Adult
PubMed: 35397995
DOI: 10.1016/j.clae.2022.101595