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Targeted delivery of drugs into specific cancer cells is an effective way to enhance the efficacy and minimize the side effects of therapy. Prostate malignant cells overexpress the prostate-specific membrane antigen (PSMA), a membrane protein that may be a valid target for selective drug administration. To target prostate cancer cells, a ß-cyclodextrin perfunctionalised with dipeptide-like urea arms, a well-established mimic of a selective ligand against PSMA, is herein reported, to develop a multivalent drug delivery and targeting system. Firstly, fluorescein was used to validate the system on cells that express high levels of PSMA (prostate tumoral cells, LNCap) or very low levels of PSMA (non-tumoral cells, Hek293T). Then, the antineoplastic agent doxorubicin complexed with ß-cyclodextrin functionalized with PSMA-like ligand takes less time to induce cytotoxicity on LNCap cells compared to doxorubicin alone. This might represent a promising drug-delivery approach to selectively target prostate cancer cells.
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Neoplasias de la Próstata , beta-Ciclodextrinas , Antígenos de Superficie/metabolismo , Línea Celular Tumoral , Doxorrubicina/farmacología , Glutamato Carboxipeptidasa II/metabolismo , Células HEK293 , Humanos , Ligandos , Masculino , Neoplasias de la Próstata/patología , Urea/farmacología , Urea/uso terapéuticoRESUMEN
The synthesis of d-glucoheptose derivative containing a boronic moiety is described herein. Starting from benzyl 6,7-dideoxy-2,3,4-tri-O-benzyl-ß-d-gluco-ept-6-enopyranoside, the introduction of the boronic acid was performed through a metathesis reaction by using MIDA vinyl boronic acid and the 2nd generation Grubbs catalyst. Hydrogenation led to the final product in only two reaction steps. This new sugar-containing boronic acid in the skeleton could mimic carbohydrate behavior and follow the glucose uptake in living cells. The in vitro toxicity tests performed in fibroblasts and glioma tumor cell lines showed minimal toxicity. Boron uptake measured using ICP-MS was minimal in fibroblasts, while in glioma cells showed a value of 6 ng of total boron accumulation per mg of cells, implying that compound 1a is able to accumulate selectively in the tumor tissues compared to normal.
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Terapia por Captura de Neutrón de Boro , Glioma , Boro/farmacología , Compuestos de Boro/farmacología , Ácidos Borónicos/farmacología , Carbohidratos , Línea Celular Tumoral , Glioma/metabolismo , Glucosa , HumanosRESUMEN
The preparation of anomeric tetrabutylammonium sulphates of glucose and galactose derivatives is reported and their role as donors in glycosylation reactions is studied. Metal triflates showed good performance in activating sulphate as a leaving group. Among them, ytterbium triflate in stoichiometric amounts gave the best results. Basic conditions using barium oxide in combination with trimethylsilyl trifluoromethanesulfonate (TMSOTf) were also shown to give good results. Benzylated sulphates were much more reactive than benzoylated donors when activated either by ytterbium triflate or by BaO and TMSOTf. Different acceptors were tested, such as isopropanol, cholesterol, and other common sugar derivatives. High reaction rates and excellent glycosylation yields were obtained under mild reaction conditions. The α/ß anomeric ratio suggests a predominant SN2-like reaction mechanism.
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After the development of accelerators as neutron source, the access to new suitable agents for boron neutron capture therapy (BNCT) became a major need. Among many others, sugar boronic acids have recently attracted attention as boron carriers. Herein we report the synthesis and preliminary biological studies of two new sugar analogues containing a boronic acid at the anomeric position. The analogues were obtained by hydroboration of proper open-chain terminal alkenes that, after quenching with water, spontaneously afforded cyclic boronic acids with hemiacetal-like structures.
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AIM: Boron Neutron Capture Therapy (BNCT) is a binary hadrontherapy which exploits the neutron capture reaction in boron, together with a selective uptake of boronated substances by the neoplastic tissue. There is increasing evidence that future improvements in clinical BNCT will be triggered by the discovery of new boronated compounds, with higher selectivity for the tumor with respect to clinically used sodium borocaptate (BSH) and boronophenylalanine (BPA). BACKGROUND: Therefore, a (10)B quantification technique for biological samples is needed in order to evaluate the performance of new boronated formulations. MATERIALS AND METHODS: This article describes an improved neutron autoradiography set-up employing radiation sensitive films where the latent tracks are made visible by proper etching conditions. RESULTS: Calibration curves for both liquid and tissue samples were obtained. CONCLUSIONS: The obtained calibration curves were adopted to set-up a mechanism to point out boron concentration in the whole sample.
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STUDY QUESTION: Does antimicrobial peptide, LL-37, inhibit sperm fertilizing ability? SUMMARY ANSWER: Our results indicate that LL-37 inhibits mouse and human sperm fertilizing ability. WHAT IS KNOWN ALREADY: LL-37, a cationic antimicrobial peptide, exerts its microbicidal effects through the disruption of microbial cytoplasmic membranes following its interaction with microbial surface anionic phospholipids. ALL-38 (an LL-37 close analogue: LL-37 + Ala at the N-terminus) is produced in the vagina 2-6 h post-intercourse from its precursor hCAP-18, a seminal plasma component. At this time, motile sperm have already swum into the uterine cavity, thus unexposed to ALL-38. Since sperm contain a substantial amount of acidic sulfogalactosylglycerolipid (SGG) on their surface, treatment of sperm with LL-37 may cause their membrane disruption in an analogous manner to that occurring on microbial membranes. STUDY DESIGN, SIZE AND DURATION: Mouse/human sperm treated (2-30 min) with LL-37 in a physiological concentration range (up to 10.8 µM) were assessed for SGG-dependent LL-37 binding, and parameters relevant to fertilizing ability, namely motility and intactness of the sperm acrosome and plasma membrane. Ability of mouse sperm to fertilize eggs in vitro was also evaluated. Each study was performed with greater than or equal to three different sperm samples. The efficacy of LL-37 to inhibit sperm fertilizing ability in vivo was determined in female mice (n = 26 each for LL-37 treatment and no treatment), using sperm retrieved from 26 males. PARTICIPANTS/MATERIALS, SETTING, METHODS: Human sperm samples were donated by fertile men. LL-37 was chemically synthesized and was biotinylated for sperm binding studies. Sperm motility was assessed by videomicroscopy and the acrosomal status by Coomassie blue staining of acrosome-intact mouse sperm or the exposure of CD46, an inner acrosomal membrane protein, of acrosome reacted human sperm. Sperm membrane permeabilization/disruption was assessed by the loss of hypo-osmotic swelling response, an incorporation of Sytox Green (a membrane impermeable fluorescent DNA dye), and electron microscopy. Mouse IVF was scored by the presence of two pronuclei in eggs 6 h post-insemination. Ability of mouse sperm to fertilize eggs in vivo was determined by the pregnancy outcome of female mice injected transcervically with sperm with or without LL-37. MAIN RESULTS AND THE ROLE OF CHANCE: Biotinylated LL-37 bound to both mouse and human sperm and the binding was partially dependent on sperm surface SGG. Mouse and human sperm became immotile and underwent a premature acrosome reaction upon treatment with LL-37 at 3.6 and 10.8 µM, respectively. The initial action of LL-37 on both mouse and human sperm appeared to be through permeabilization/disruption of sperm surface membranes evidenced by the loss of hypo-osmotic swelling response, Sytox Green staining and electron microscopy revealing ultrastructural damage. Mouse sperm treated with 3.6 µM LL-37 lost the ability to fertilize eggs both in vitro and in vivo. All 26 female mice inseminated with sperm and LL-37 did not become pregnant. No apparent damage to the reproductive tract was observed as revealed by histological characterization in LL-37-inseminated mice and these females resumed fecundity following mating with fertile males. LIMITATIONS, REASONS FOR CAUTION: Direct demonstration that LL-37 treated human sperm fail to fertilize eggs was limited by legal restrictions on obtaining human eggs for such use. WIDER IMPLICATIONS OF THE FINDINGS: Our results reveal selective inhibitory effects of LL-37 on sperm fertilizing ability in mice without apparent impairment to the female reproductive tract. LL-37 is therefore a promising candidate to be developed into a vaginal contraceptive with microbicidal activity. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by Grand Challenges Explorations grant from the Bill & Melinda Gates Foundation (OPP1024509), Canadian Institutes of Health Research (MOP119438 & CCI82413) and International Collaboration and Exchanges NSFC of China (No.30611120525). There are no competing interests to declare.
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Péptidos Catiónicos Antimicrobianos/farmacología , Anticonceptivos , Fertilización/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Acrosoma/efectos de los fármacos , Animales , Femenino , Humanos , Masculino , Ratones , Motilidad Espermática/efectos de los fármacos , Interacciones Espermatozoide-Óvulo/efectos de los fármacos , CatelicidinasRESUMEN
CD1e is a member of the CD1 family that participates in lipid antigen presentation without interacting with the T-cell receptor. It binds lipids in lysosomes and facilitates processing of complex glycolipids, thus promoting editing of lipid antigens. We find that CD1e may positively or negatively affect lipid presentation by CD1b, CD1c, and CD1d. This effect is caused by the capacity of CD1e to facilitate rapid formation of CD1-lipid complexes, as shown for CD1d, and also to accelerate their turnover. Similar results were obtained with antigen-presenting cells from CD1e transgenic mice in which lipid complexes are assembled more efficiently and show faster turnover than in WT antigen-presenting cells. These effects maximize and temporally narrow CD1-restricted responses, as shown by reactivity to Sphingomonas paucimobilis-derived lipid antigens. CD1e is therefore an important modulator of both group 1 and group 2 CD1-restricted responses influencing the lipid antigen availability as well as the generation and persistence of CD1-lipid complexes.
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Antígenos CD1/inmunología , Inmunidad/inmunología , Lípidos/inmunología , Animales , Presentación de Antígeno/inmunología , Células Clonales , Células Dendríticas/inmunología , Glucolípidos/inmunología , Glicoproteínas/inmunología , Infecciones por Bacterias Gramnegativas/inmunología , Humanos , Cinética , Ratones , Ratones Transgénicos , Células T Asesinas Naturales/inmunología , Sphingomonas/inmunologíaRESUMEN
INTRODUCTION: Cardiopulmonary exercise testing (CPET) is nowadays used to study the exercise response in healthy subjects and in disease. Ventilatory efficiency is one of the main determinants in exercise tolerance, and its main variables are a useful tool to guide pathophysiologists toward specific diagnostic pathways, providing prognostic information and improving disease management, treatment, and outcomes. AREAS COVERED: This review will be based on today's available scientific evidence, describing the main physiological determinants of ventilatory efficiency at rest and during exercise, and focusing also on how CPET variables are modified in specific diseases, leading to the possibility of early diagnosis and management. EXPERT OPINION: Growing knowledge on CPET interpretation and a wider use of this clinical tool is expected in order to offer more precise diagnostic and prognostic information to patients and clinicians, helping in the management of therapeutic decisions. Future research could be able to identify new and more simple markers of ventilatory efficiency, and to individuate new interventions for the improvement of symptoms, such as exertional dyspnea.
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Prueba de Esfuerzo , Tolerancia al Ejercicio , Intercambio Gaseoso Pulmonar , Humanos , Intercambio Gaseoso Pulmonar/fisiología , Ventilación Pulmonar/fisiología , Ejercicio Físico/fisiología , Pronóstico , Pulmón/fisiopatologíaRESUMEN
INTRODUCTION: DOK7 gene deficiency is a neuromuscular disease with an alteration in post-synaptic neuromuscular junction, leading to progressive respiratory impairment. Although, the therapy is not standardized, adrenergic agonists are suggested as first-line treatment. Case presentation: Our patient had an ambiguous late childhood-onset and had a generalized muscle weakness free of respiratory symptoms during the early phase of the disease. Subsequently, when the respiratory muscle and the diaphragm involvement was impaired, a substantial loss of respiratory function with hypopneas and severe desaturation was detected. It was noteworthy the striking respiratory beneficial impact of oral salbutamol in the resolution of symptoms and functional impairments, leading to a remarkable respiratory improvement and a better quality of life. Conclusion: Oral salbutamol treatment combined to a timely clinical recognition led to an outstanding respiratory improvement.
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Asymmetric epoxidation represents a hot topic in organic synthesis. In recent years, organocatalysts based on sugar skeletons have been exploited in asymmetric epoxidation to achieve enantiomeric pure epoxides. In this work, two different endocyclic ketones derived from glucose and galactose protected with a 4,6-O-benzylidene group have been prepared and exploited for Shi-type epoxidation. The two carbohydrates show an opposite preferential stereoselective epoxidation on various olefins, affording the epoxides in high conversions and modest enantioselectivities. DFT calculations disclosed the reasons behind the inversion of selectivity achieved by the two catalysts, showing that a delicate balance between the catalyst conformation, its protecting groups, and the secondary interactions with the substrate govern the final observed results.
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BACKGROUND: Long COVID is defined as persistency of symptoms, such as exertional dyspnea, twelve weeks after recovery from SARS-CoV-2 infection. OBJECTIVES: To investigate ventilatory efficiency by the use of cardiopulmonary exercise testing (CPET) in patients with exertional dyspnea despite normal basal spirometry after 18 (T18) and 36 months (T36) from COVID-19 pneumonia. METHODS: One hundred patients with moderate-critical COVID-19 were prospectively enrolled in our Long COVID program. Medical history, physical examination and lung high-resolution computed tomography (HRCT) were obtained at hospitalization (T0), 3 (T3) and 15 months (T15). All HRCTs were revised using a semi-quantitative CT severity score (CSS). Pulmonary function tests were obtained at T3 and T15. CPET was performed in a subset of patients with residual dyspnea (mMRC ≥ 1), at T18 and at T36. RESULTS: Remarkably, at CPET, ventilatory efficiency was reduced both at T18 (V'E/V'CO2 slope = 31.4±3.9â¯SD) and T36 (V'E/V'CO2 slope = 31.28±3.70â¯SD). Furthermore, we identified positive correlations between V'E/V'CO2 slope at T18 and T36 and both percentage of involvement and CSS at HRCT at T0, T3 and T15. Also, negative linear correlations were found between V'E/V'CO2 slope at T18 and T36 and DLCO at T3 and T15. CONCLUSIONS: At eighteen months from COVID-19 pneumonia, 20â¯% of subjects still complains of exertional dyspnea. At CPET this may be explained by persistently reduced ventilatory efficiency, possibly related to the degree of lung parenchymal involvement in the acute phase of infection, likely reflecting a damage in the pulmonary circulation.
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COVID-19 , Disnea , Humanos , COVID-19/fisiopatología , COVID-19/complicaciones , Masculino , Disnea/fisiopatología , Disnea/etiología , Femenino , Persona de Mediana Edad , Anciano , Prueba de Esfuerzo , Tomografía Computarizada por Rayos X , Pruebas de Función Respiratoria , Estudios Prospectivos , Pulmón/fisiopatología , Pulmón/diagnóstico por imagen , Espirometría , SARS-CoV-2 , Ventilación Pulmonar/fisiologíaRESUMEN
Given the renewed interest in boron neutron capture therapy (BNCT) and the intensified search for improved boron carriers, as well as the difficulties of coherently comparing the carriers described so far, it seems necessary to define a basic set of assays and standardized methods to be used in the early stages of boron carrier development in vitro. The selection of assays and corresponding methods is based on the practical experience of the authors and is certainly not exhaustive, but open to discussion. The proposed tests/characteristics: Solubility, lipophilicity, stability, cytotoxicity, and cellular uptake apply to both low molecular weight (up to 500 Da) and high molecular weight (5000 Da and more) boron carriers. However, the specific methods have been selected primarily for low molecular weight boron carriers; in the case of high molecular weight compounds, some of the methods may need to be adapted.
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Compuestos de Boro , Terapia por Captura de Neutrón de Boro , Peso Molecular , Humanos , Compuestos de Boro/química , Terapia por Captura de Neutrón de Boro/métodosRESUMEN
The discovery of new glycosylation reactions is still a major challenge in carbohydrate chemistry. Traditional glycosylation reactions require the preparation of sugar donors with anomeric active or latent leaving groups. Dehydrative glycosylation is a fascinating alternative that enables the direct formation of the glycosidic bond from the hemiacetal, eliminating the need for (sometimes unstable) leaving groups, and allowing to reduce reaction, work-up, and purification times. Although some interesting methods of dehydrative glycosylation have been reported, in order to compete with conventional chemical glycosylation, a greater number of efficient and stereoselective methods need to be developed. Herein, a dehydrative procedure that uses a combination of iodine, triphenylphosphine, and a base (DMAP or imidazole) is described. This methodology allows for the preparation of sugar derivatives from commercially available 1-hydroxy glycosyl donors. The reaction takes place under mild conditions through the in situ-formation of an anomeric iodide intermediate, which, upon reaction with an alcohol, gives the corresponding glycosides up to quantitative yields and with high α-stereoselectivity.
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Yodo , Glicosilación , Compuestos Organofosforados , Química Orgánica , GlicósidosRESUMEN
Glycosylation is the key reaction by which our body can produce and modify carbohydrates and their conjugates which are molecules essential for life. The study of the diversity of their functions is a current and ever-expanding topic that requires the ability to provide pure saccharides quickly, efficiently and in a controlled way which can be achieved by chemical synthesis. Although the influence of the donor and the promoter on the outcome of a glycosylation reaction is well documented, the search for new methodologies and new promoters/activators is constantly expanding. In this review, after an introduction dealing with well-known glycosylation strategies, we describe the most recent advances in terms of the use of innovative approaches, focalizing the study on new promoters and leaving groups exploited in the last ten years.
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Carbohidratos , Carbohidratos/química , Glicosilación , EstereoisomerismoRESUMEN
Sugars are a versatile tool for targeting malignant cells and have been extensively used for drug delivery and imaging techniques. Their prototype, fluorodeoxyglucose ([18F]FDG), is currently used for positron emission tomography. Boron neutron capture therapy (BNCT) is a cancer treatment that relies on irradiation with thermal neutrons of cancer cells previously loaded with [10B]-containing compounds. The recent introduction of accelerators as a neutron source for clinical use prompts the planning of delivery compounds enriched with boron able to be traced in real time. This work describes the first synthesis of a new class of sugar derivatives conjugated to a trifluoroborate moiety as potential theranostic agents. Stability and cytotoxicity studies are reported for all compounds, together with [18F] radiolabeling optimization and in vivo preliminary positron emission tomography (PET) experiments on a selected compound.
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The Hendrickson reagent is able to perform efficiently dehydrative glycosylation of 1-hydroxyglycosyl donors. The reaction occurs under mild conditions through an anomeric oxophosphonium intermediate detected by nuclear magnetic resonance. Further insight into the mechanism was gained by (18)O labeling of anomeric OH.
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Glicósidos/química , Indicadores y Reactivos/química , Glicosilación , Espectroscopía de Resonancia Magnética , Estructura MolecularRESUMEN
Grape seeds are among the main constituents of grape pomace, ranging between 20% and 30% of the wet matrix; however, their oligosaccharide composition has not been studied. This paper describes the purification and the identification of low molecular weight oligosaccharides contained in an EtOH/water extract of grape seeds. A sequential two-step purification by size exclusion chromatography was carried out to fractionate compounds according to molecular weights. Chemical characterization of the combined fractions was performed by Magnetic Resonance Spectroscopy and Gas Chromatography-Mass Spectrometry analyses. The separation process gave two fractions abundant in sucrose and glucose. A third fraction containing trisaccharides was acetylated allowing the purification of the main trisaccharide. The structure elucidation of the acetylated product made it possible to identify gentianose, a predominant carbohydrate reserve found in the storage roots of perennial Gentiana lutea. Grape seeds are wine industry by-products and the obtained results suggest the importance of their recovery.
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Oligosacáridos/química , Vitis/metabolismo , Fraccionamiento Químico , Cromatografía en Gel , Cromatografía en Capa Delgada , Cromatografía de Gases y Espectrometría de Masas , Oligosacáridos/aislamiento & purificación , Semillas/metabolismoRESUMEN
Boron neutron capture therapy (BNCT) has the potential to specifically destroy tumor cells without damaging the tissues infiltrated by the tumor. BNCT is a binary treatment method based on the combination of two agents that have no effect when applied individually: 10B and thermal neutrons. Exclusively, the combination of both produces an effect, whose extent depends on the amount of 10B in the tumor but also on the organs at risk. It is not yet possible to determine the 10B concentration in a specific tissue using non-invasive methods. At present, it is only possible to measure the 10B concentration in blood and to estimate the boron concentration in tissues based on the assumption that there is a fixed uptake of 10B from the blood into tissues. On this imprecise assumption, BNCT can hardly be developed further. A therapeutic approach, combining the boron carrier for therapeutic purposes with an imaging tool, might allow us to determine the 10B concentration in a specific tissue using a non-invasive method. This review provides an overview of the current clinical protocols and preclinical experiments and results on how innovative drug development for boron delivery systems can also incorporate concurrent imaging. The last section focuses on the importance of proteomics for further optimization of BNCT, a highly precise and personalized therapeutic approach.
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Seminolipid, also known as sulfogalactosylglycerolipid (SGG), plays important roles in male reproduction. Therefore, an accurate and sensitive method for SGG quantification in testes and sperm is needed. Here we compare SGG quantitation by the traditional colorimetric Azure A assay with LC-ESI-MS/MS using multiple reaction monitoring (MRM). Inclusion of deuterated SGG as the internal standard endowed accuracy to the MRM method. The results showed reasonable agreement between the two procedures for purified samples, but for crude lipid extracts, the colorimetric assay significantly overestimated the SGG content. Using ESI-MS/MS MRM, C16:0-alkyl/C16:0-acyl SGG of Cgt(+/â») mice was quantified to be 406.06 ± 23.63 µg/g testis and 0.13 ± 0.02 µg/million sperm, corresponding to 78% and 87% of the wild-type values, respectively. CGT (ceramide galactosyltransferase) is a critical enzyme in the SGG biosynthesis pathway. Cgtâ»/â» males depleted of SGG are infertile due to spermatogenesis arrest. However, Cgt(+/â») males sire offspring. The higher than 50% expression level of SGG in Cgt(+/â») animals, compared with the wild-type expression, might be partly due to compensatory translation of the active CGT enzyme. The results also indicated that 78% of SGG levels in Cgt(+/â») mice were sufficient for normal spermatogenesis.
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Cromatografía Liquida/métodos , Glucolípidos/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Animales , Colorimetría/métodos , Femenino , Glucolípidos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , N-Acilesfingosina Galactosiltransferasa/metabolismo , Sensibilidad y Especificidad , Espermatozoides/metabolismo , Testículo/metabolismoRESUMEN
The first synthesis of the sulfonate analogue of seminolipid, the main sulfoglycolipid in mammalian sperm, is reported. Installation of the sulfonate unit was accomplished by a quite unexplored strategy based on Horner-Wadsworth-Emmons olefination on a 3 '-keto-galactoside, followed by stereoselective double bond reduction.