Search Results (7)

Boron (B) neutron capture therapy (BNCT) is a novel non-invasive targeted cancer therapy based on the nuclear capture reaction ¹⁰B (n, alpha) ⁷Li that enables the death of cancer cells without damaging neighboring normal cells. However, the development of clinically approved boron drugs remains challenging. We have previously reported on self-forming nanoparticles for drug delivery consisting of a biodegradable polymer, namely, “AB-type” Lactosome^® nanoparticles (AB-Lac particles)- highly loaded with hydrophobic B compounds, namely o-Carborane (Carb) or 1,2-dihexyl-o-Carborane (diC6-Carb), and the latter (diC6-Carb) especially showed the “molecular glue” effect. Here we present in vivo and ex vivo studies with human pancreatic cancer (AsPC-1) cells to find therapeutically optimal formulas and the appropriate treatment conditions for these particles. The biodistribution of the particles was assessed by the tumor/normal tissue ratio (T/N) in terms of tumor/muscle (T/M) and tumor/blood (T/B) ratios using near-infrared fluorescence (NIRF) imaging with indocyanine green (ICG). The in vivo and ex vivo accumulation of B delivered by the injected AB-Lac particles in tumor lesions reached a maximum by 12 h post-injection. Irradiation studies conducted both in vitro and in vivo showed that AB-Lac particles-loaded with either ¹⁰B-Carb or ¹⁰B-diC6-Carb significantly inhibited the growth of AsPC-1 cancer cells or strongly inhibited their growth, with the latter method being significantly more effective. Surprisingly, a similar in vitro and in vivo irradiation study showed that ICG-labeled AB-Lac particles alone, i.e., without any ¹⁰B compounds, also revealed a significant inhibition. Therefore, we expect that our ICG-labeled AB-Lac particles-loaded with ¹⁰B compound(s) may be a novel and promising candidate for providing not only NIRF imaging for a practical diagnosis but also the dual therapeutic effects of induced cancer cell death, i.e., “theranostics”. Full article

A new luminescent hybrid material based on silica aerogel and a boron-containing coordination compound with 8-hydroxyquinoline was created, and its physicochemical and spectral-luminescent characteristics were studied. A simple scheme for the synthesis of a hybrid luminescent material was developed. Simultaneously with the synthesis of the aerogel, the formation of a boron-containing phosphor was carried out using an isopropanol solution of boric acid and 8-hydroxyquinoline. Using in situ luminescent measurements, the mechanisms of the formation of boron-based luminescent complexes in isopropanol and tetrahydrofuran media were established. Both hydrophilic and hydrophobic silica aerogels were tested as matrices for the hybrid material. The formation of a thin layer of a boron-containing coordination luminescent compound on the highly developed surface of the SiO₂ aerogel made it possible to strongly stabilize the aerogel structure and noticeably increase the thermal stability of the synthesized hybrid material. Full article

Chlamydia trachomatis, a parasitic intracellular bacterium, is a major human pathogen that causes millions of trachoma, sexually transmitted infections, and pneumonia cases worldwide. Previously, peptidomimetic inhibitors consisting of a hydrophobic dipeptide derivative exhibited significant inhibitory effects against chlamydial growth. Based on this finding, this study showed that both bortezomib (BTZ) and ixazomib (IXA), anticancer drugs characterized by proteasome inhibitors, have intensive inhibitory activity against Chlamydia. Both BTZ and IXA consisted of hydrophobic dipeptide derivatives and strongly restricted the growth of Chlamydia (BTZ, IC₅₀ = 24 nM). In contrast, no growth inhibitory effect was observed for other nonintracellular parasitic bacteria, such as Escherichia coli. BTZ and IXA appeared to inhibit chlamydial growth bacteriostatically via electron microscopy. Surprisingly, Chlamydia-infected cells that induced a persistent infection state were selectively eliminated by BTZ treatment, whereas uninfected cells survived. These results strongly suggested the potential of boron compounds based on hydrophobic dipeptides for treating chlamydial infections, including persistent infections, which may be useful for future therapeutic use in chlamydial infectious diseases. Full article

Curcumin, an active component of the rhizome turmeric, has gained much attention as a plant-based compound with pleiotropic pharmacological properties. It possesses anti-inflammatory, antioxidant, hypoglycemic, antimicrobial, neuroprotective, and immunomodulatory activities. However, the health-promoting utility of curcumin is constrained due to its hydrophobic nature, water insolubility, poor bioavailability, rapid metabolism, and systemic elimination. Therefore, an innovative stride was taken, and complexes of metals with curcumin have been synthesized. Curcumin usually reacts with metals through the β-diketone moiety to generate metal–curcumin complexes. It is well established that curcumin strongly chelates several metal ions, including boron, cobalt, copper, gallium, gadolinium, gold, lanthanum, manganese, nickel, iron, palladium, platinum, ruthenium, silver, vanadium, and zinc. In this review, the pharmacological, chemopreventive, and therapeutic activities of metal–curcumin complexes are discussed. Metal–curcumin complexes increase the solubility, cellular uptake, and bioavailability and improve the antioxidant, anti-inflammatory, antimicrobial, and antiviral effects of curcumin. Metal–curcumin complexes have also demonstrated efficacy against various chronic diseases, including cancer, arthritis, osteoporosis, and neurological disorders such as Alzheimer’s disease. These biological activities of metal–curcumin complexes were associated with the modulation of inflammatory mediators, transcription factors, protein kinases, antiapoptotic proteins, lipid peroxidation, and antioxidant enzymes. In addition, metal–curcumin complexes have shown usefulness in biological imaging and radioimaging. The future use of metal–curcumin complexes may represent a new approach in the prevention and treatment of chronic diseases. Full article

The development of novel, tumor-selective and boron-rich compounds as potential agents for use in boron neutron capture therapy (BNCT) represents a very important field in cancer treatment by radiation therapy. Here, we report the design and synthesis of two promising compounds that combine meta-carborane, a water-soluble monosaccharide and a linking unit, namely glycine or ethylenediamine, for facile coupling with various tumor-selective biomolecules bearing a free amino or carboxylic acid group. In this work, coupling experiments with two selected biomolecules, a coumarin derivative and folic acid, were included. The task of every component in this approach was carefully chosen: the carborane moiety supplies ten boron atoms, which is a tenfold increase in boron content compared to the l-boronophenylalanine (l-BPA) presently used in BNCT; the sugar moiety compensates for the hydrophobic character of the carborane; the linking unit, depending on the chosen biomolecule, acts as the connection between the tumor-selective component and the boron-rich moiety; and the respective tumor-selective biomolecule provides the necessary selectivity. This approach makes it possible to develop a modular and feasible strategy for the synthesis of readily obtainable boron-rich agents with optimized properties for potential applications in BNCT. Full article

A systematic evaluation of eight different coatings made of solid phase extraction (SPE) and carbon-based sorbents immobilized with polyacrylonitrile in the thin-film microextraction (TFME) format using LC-MS/MS was described. The investigated coatings included graphene, graphene oxide, multi-walled carbon nanotubes (MWCNTs), carboxylated MWCNTs, as carbon-based coatings, and polystyrene-divinylbenzene (PS-DVB), octadecyl-silica particles (C18), hydrophilic–hydrophobic balance particles (HLB) and phenyl-boronic acid modified particles (PBA), as SPE-based coatings. A total of 24 compounds of diverse moieties and of a wide range of polarities (log P from −2.99 to 6.98) were selected as probes. The investigated coatings were characterized based on their extraction performance toward the selected probes at different pH values and at optimized desorption conditions. In the case of SPE-based coatings, PS-DVB and HLB exhibited a balanced extraction for compounds within a wide range of polarities, and C18 showed superior extraction recoveries for non-polar analytes. Carbon-based coatings showed high affinity for non-polar compounds given that their main driving force for extraction is hydrophobic interactions. Interestingly, among the studied carbon-based coatings, graphene oxide showed the best extraction capabilities toward polar compounds owing to its oxygen-containing groups. Overall, this work provided important insights about the extraction mechanisms and properties of the investigated coatings, facilitating the coating selection when developing new TFME applications. Full article

4-Phenyl-1,8-naphthalimide was synthesized by imidation of commercially available 4-bromo-1,8-naphthalic anhydride, followed by Suzuki coupling with phenyl boronic acid, both under microwave heating. The microwave-assisted reactions were found to be faster and more efficient than reactions carried out by heating in oil-baths. While this compound was quite fluorescent in solvents such as chloroform, methanol and ethanol, it is virtually non-fluorescent in DMSO; however, upon the addition of water to DMSO solutions of this dye, fluorescence was restored, suggesting a tendency for aggregation-induced emission. The fluorescent properties of 4-phenyl-1,8-naphthalimide were found to be influenced by salt concentrations, likely as a result of hydrophobic effects. While this dye does not show binding to DNA, presence of bovine serum albumin leads to effective fluorescence quenching. Full article