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Objectives: To evaluate whether the glycosylation of chrysin (CHR) enhances its protective effects against aluminum-induced neurotoxicity. Methods: To compare the antioxidant, anticholinesterase, and behavioral effects of CHR with its glycosylated form (CHR bonded to β-d-glucose tetraacetate, denoted as LQFM280), we employed an integrated approach using both in vitro (SH-SY5Y cells) and in vivo (aluminum-induced neurotoxicity in Swiss mice) models. Key findings: LQFM280 demonstrated higher antioxidant activity than CHR in both models. Specifically, LQFM280 exhibited the ability to exert antioxidant effects in the cytoplasm of SH-SY5Y cells, indicating its competence in traversing neuronal membranes. Remarkably, LQFM280 proved more effective than CHR in recovering memory loss and counteracting neuronal death in the aluminum chloride mice model, suggesting its increased bioavailability at the brain level. Conclusions: The glycosylation of CHR with β-d-glucose tetraacetate amplifies its neuroprotective effects, positioning LQFM280 as a promising lead compound for safeguarding against neurodegenerative processes involving oxidative stress. Graphical Abstract [ABSTRACT FROM AUTHOR]

Advances have been made in the search for new multi-target modulators to control pain and inflammation. Therefore, compound 3,5-di-tert-butyl-4-hydroxyphenyl)(4-methylpiperazin-1-yl)methanone (LQFM202) was synthesised and evaluated. First, in vitro assays were performed for COX-1, COX-2, and 5-LOX enzymes. Subsequently, adult female Swiss albino mice treated orally with LQFM202 at doses of 25–200 mg/kg were subjected to acetic acid-induced writhing, formalin-induced pain, carrageenan-induced hyperalgesia, carrageenan- or zymosan-induced paw oedema, or pleurisy. LQFM202 inhibited COX-1, COX-2, and LOX-5 (IC50 = 3499 µM, 1565 µM, and 1343 µM, respectively). In acute animal models, LQFM202 (50, 100, or 200 mg/kg) decreased the amount of abdominal writhing (29%, 52% and 48%, respectively). Pain in the second phase of the formalin test was reduced by 46% with intermediate dose. LQFM202 (100 mg/kg) reduced the difference in nociceptive threshold in all 4 h evaluated (46%, 37%, 30%, and 26%, respectively). LQFM202 (50 mg/kg) decreased the carrageenan-oedema from the second hour (27%, 31% and 25%, respectively); however, LQFM202 (100 mg/kg) decreased the carrageenan-oedema in all hours evaluated (35%, 42%, 48% and 50%, respectively). When using zymosan, LQFM202 (50 mg/kg) decreased the oedema in all hours evaluated (33%, 32%, 31% and 20%, respectively). In the carrageenan-pleurisy test, LQFM202 (50 mg/kg) reduced significantly the number of polymorphonuclear cells (34%), the myeloperoxidase activity (53%), TNF-α levels (47%), and IL-1β levels (58.8%). When using zymosan, LQFM202 (50 mg/kg) reduced the number of polymorphonuclear and mononuclear cells (54% and 79%, respectively); and the myeloperoxidase activity (46%). These results suggest antinociceptive and anti-inflammatory effects of LQFM202. [ABSTRACT FROM AUTHOR]

Conductive polymers can stimulate the adhesion and proliferation of several cell types being an interesting material to be applied in the field of tissue engineering. In this application, the addition of a thermosensitive polymer has been pointed out as an attractive strategy to improve mechanical strength and to provide conformation changes at temperature close to human body temperature. The main goal of this work was to evaluate the physical–chemical properties and promotion of cell proliferation and possible application as scaffolds for tissue engineering of blends of poly(N‐vinylcaprolactam) (PNVCL) and poly(N‐vinylcaprolactam‐co‐butylacrylate) (PNVCL‐co‐ABu) with poly(3‐hexylthiophene) (P3HT). Both polymers were synthesized and their chemical structures were confirmed by Fourier Transform Infrared (FT‐IR) and nuclear magnetic resonance (NMR) analyses. The materials were processed in films form for structural characterization, impedance measurements, and thermogravimetric analysis. The in vitro biological assays were performed using the materials as electrospun mats. The FT‐IR was also used to characterize the blends. The addition of P3HT did not change thermal stability and showed low conductivity values of the blends. Comparing the in vitro behavior of the blends and the polymers it was possible to conclude that the presence of P3HT improved cytocompatibility and promoted cell proliferation. [ABSTRACT FROM AUTHOR]

Intranasal administration of mucus-penetrating nanoparticles is an emerging trend to increase drug delivery to the brain. In order to overcome rapid nasal mucociliary clearance, low epithelial permeation, and local enzymatic degradation, we investigated the influence of PEGylation on nose-to-brain delivery of polycaprolactone (PCL) nanoparticles (PCL-NPs) encapsulating bexarotene, a potential neuroprotective compound. PEGylation with 1, 3, 5, and 10% PCL-PEG did not affect particle diameter or morphology. Upon incubation with artificial nasal mucus, only 5 and 10% of PCL-PEG coating were able to ensure NP stability and homogeneity in mucus. Rapid mucus-penetrating ability was observed for 98.8% of PCL-PEG5% NPs and for 99.5% of PCL-PEG10% NPs. Conversely, the motion of non-modified PCL-NPs was markedly slower. Fluorescence microscopy showed that the presence of PEG on NP surface did not reduce their uptake by RMPI 2650 cells. Fluorescence tomography images evidenced higher translocation into the brain for PCL-PEG5% NPs. Bexarotene loaded into PCL-PEG5% NPs resulted in area under the curve in the brain (AUCbrain) 3 and 2-fold higher than that for the drug dispersion and for non-PEGylated NPs (p < 0.05), indicating that approximately 4% of the dose was directly delivered to the brain. Combined, these results indicate that PEGylation of PCL-NPs with PCL-PEG5% is able to reduce NP interactions with the mucus, leading to a more efficient drug delivery to the brain following intranasal administration. [ABSTRACT FROM AUTHOR]

Factors that reduce the quality of common bean during storage, including oxidative rancidity caused by lipoxygenase, have been extensively studied. In this context, this work evaluates lipoxygenase activity in five Carioca bean cultivars at different temperatures and storage times using ultraviolet (UV) and nuclear magnetic resonance (NMR) spectroscopies. UV absorption analyses demonstrated that the storage temperature of the grains influences the kinetic reaction rates during the enzymatic activity of lipoxygenase. Pinto beans and CNFC 10467 presented lower initial activity than the three BRS varieties but were more sensitive to high temperatures. BRS Estilo presented an anomalous behavior, with a strong reduction in activity at 15 and 21 °C until 72 days of storage. BRSMG Madrepérola and BRS Pontal presented stable enzymatic rates until 108 days of storage. A 26% reduction in fatty acid content, as a result of lipoxygenase action during storage, was observed both in solution-state and high resolution magic angle spinning (HR-MAS) NMR studies. These results highlight the importance of NMR in enzymatic kinetic reactions studies, complementing the results obtained by UV. [ABSTRACT FROM AUTHOR]

This work describes the isolation and structural elucidation of compounds from the leaves of Myrcia tomentosa (Aubl.) DC. (goiaba-brava) and evaluates the antimicrobial activity of the crude extract, fractions and isolated compounds against bacteria and fungi. Column chromatography was used to fractionate and purify the extract of the M. tomentosa leaves and the chemical structures of the compounds were determined using spectroscopic techniques. The antibacterial and antifungal activities were assessed using the broth microdilution method. The phytochemical investigation isolated 11 compounds: α-bisabolol, α-bisabolol oxide B, α-cadinol, β-sitosterol, n-pentacosane, n-tetracosane, quercetin, kaempferol, avicularin, juglanin and guaijaverin. The crude ethanolic extract and its fractions were tested against 15 bacteria and 9 yeasts. The crude extract inhibited the in vitro growth of yeasts at concentration of 4 to 32 μg/mL. The hexane, dichloromethane, ethyl acetate and aqueous fractions inhibited Candida sp. at concentrations of 4 to 256 μg/mL, whereas the Cryptococcus sp. isolates were inhibited only by the hexane and dichloromethane fractions in minimal inhibitory concentrations (MICs) at 16 to 64 μg/mL. The flavonoid quercetin-3-O-α-arabinofuranose (avicularin) was the most active compound, inhibiting Candida species in concentrations of 2 to 32 μg/mL. The MIC values suggest potential activity of this plant species against yeast. [ABSTRACT FROM AUTHOR]

In recent years, due to the rapid development of nanotechnology and the desire for breakthroughs in cementitious materials, there has been a strong research focus on the application of nanoparticles as supplementary cementitious materials (SCM) such as nanosilica (NS). This paper investigates the effect of functionalized nanosilica (NSF) with amino groups on Portland cement pastes. Fourier transform infrared (FTIR) spectroscopy, 29Si nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), and transmission electron microscopy (TEM) assays were performed to characterize the NSF and confirm the grafting of the amine organic groups on the nanosilica surface (NS). Samples of cement masses were prepared containing NSF or NS with varying content of 0.3, 0.9 and 2.7% by weight, a reference sample of cement mass was also prepared without any addition. For the characterization of cement pastes, induction calorimetry, mercury intrusion porosimetry, and compressive strength tests were performed. The results showed that NSF samples led to reduced superplasticizer use and decreased hydration rate and that the 0.9% NSF sample achieved compressive strength at 28 days greater than 50 MPa. [ABSTRACT FROM AUTHOR]