ABSTRACT
A highly bioactive glass solvBG76 in a binary system 76SiO2-24CaO (wt%) was prepared following a solvothermal path of the synthesis. The facile synthesis, in terms of the steps and reagents needed, enabled the achievement of a mesoporous material. Many factors such as nano-size (<50 nm), different morphology (non-spherical), use of an unconventional network modifier (calcium hydroxide) during the synthesis, a structure free of crystalline impurities, and textural properties greatly enhanced the kinetic deposition process of hydroxyapatite (HA) when contacting with physiological fluids. The formation of a HA layer on the glass was analyzed by various techniques, namely XRD, IR-ATR, Raman, XPS, EDS analyses, SEM, and HR-TEM imaging. The results obtained were compared to the 45S5 glass tested as a reference biomaterial as well as 70S30C-a glass with similar size and composition to reported solvBG76 but obtained by the conventional sol-gel method. For the first time, superior apatite-mineralization ability in less than 1 h in a physiological-like buffer was achieved. This unique bioactivity is accompanied by biocompatibility and hemocompatibility, which was indicated by a set of various assays in human dermal fibroblasts and MC3T3 mouse osteoblast precursor cells, as well as hemolytic activity determination.
Subject(s)
Durapatite , Glass , Animals , Apatites , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Durapatite/chemistry , Glass/chemistry , MiceABSTRACT
AIM: Ebselen (Eb) is an example of a repurposed drug with poor aqueous solubility which requires sophisticated delivery system such as nanoencapsulation in nanocapsules for topical application. MATERIALS & METHODS: Eb-nanocapsules were examined for morphology, activity against Candida spp., cytotoxicity and skin permeation. RESULTS: Eb-nanocapsules were active against skin-infecting Candida tropicalis, Candida albicans and Candida parapsilosis yeasts (minimal inhibitory concentration values were about 4-, 2- and 1.25-times lower vs free Eb, respectively) and able to suppress induced lipid oxidation in the oil/water emulsion. Moreover, demonstrated minimal toxicity in normal human dermal fibroblast cell line, whereas ex vivo skin permeation studies showed no transdermal passage and strong interactions with stratum corneum. CONCLUSION: Eb-nanocapsules represent a promising, safe and complementary alternative to the treatment of cutaneous candidiasis.
Subject(s)
Antifungal Agents/administration & dosage , Azoles/administration & dosage , Candidiasis/drug therapy , Nanocapsules/administration & dosage , Organoselenium Compounds/administration & dosage , Administration, Topical , Antifungal Agents/chemistry , Azoles/chemistry , Biopolymers/administration & dosage , Biopolymers/chemistry , Candida albicans/drug effects , Candida albicans/pathogenicity , Candidiasis/microbiology , Drug Repositioning , Emulsions/chemistry , Humans , Isoindoles , Microbial Sensitivity Tests , Nanocapsules/chemistry , Organoselenium Compounds/chemistryABSTRACT
Indoloquinoline alkaloids represent an important class of antimalarial, antibacterial and antiviral compounds. Indolo[2,3-b]quinolines are a family of DNA intercalators and inhibitors of topoisomerase II, synthetic analogs of neocryptolepine, an alkaloid traditionally used in African folk medicine. These cytotoxic substances are promising anticancer agents. Active representatives of indolo[2,3-b]quinolines affect model and natural membranes. The distinct structure and hydrophobicity of the compounds leads to marked differences in the disturbing effects on membrane organization and function. Our results also indicated a strong relationship between the presence of the chain and the Poct of the molecule as well as the capacity for incorporation into carboxyfluorescein-trapped liposomes in the 0.02-0.06 mM range. Moreover, a correlation between binding to neutral dimyristoylphosphatidylcholine (DMPC) or negative charged dimyristoylphosphatidylcholine:dimyristoylphosphatidylglycerol (DMPC:DMPG, 9:1 w/w) liposomes, as well as to erythrocyte ghosts and pKa, was also found. All the compounds cause hemolysis in isotonic conditions with concentration causing 50% hemolysis (HC50) in the 0.12-0.88 mM range. The concentration-dependent inhibitory effect of the tested agents on erythrocyte ghosts' acetylcholinesterase activity was also studied.
Subject(s)
Alkaloids/pharmacology , Antineoplastic Agents, Phytogenic/pharmacology , Cell Membrane/drug effects , Cryptolepis/chemistry , Erythrocytes/drug effects , Hemolysis/drug effects , Plant Extracts/pharmacology , Quinolines/pharmacology , Acetylcholinesterase/metabolism , Alkaloids/chemistry , Animals , Antineoplastic Agents, Phytogenic/chemistry , Cell Membrane/metabolism , Dimyristoylphosphatidylcholine/chemistry , Dose-Response Relationship, Drug , Erythrocytes/metabolism , Hydrophobic and Hydrophilic Interactions , Intercalating Agents/chemistry , Intercalating Agents/pharmacology , Liposomes , Medicine, African Traditional , Phosphatidylglycerols/chemistry , Plant Extracts/chemistry , Quinolines/chemistry , Sheep , Structure-Activity Relationship , Topoisomerase II Inhibitors/chemistry , Topoisomerase II Inhibitors/pharmacologyABSTRACT
In our previous study, we developed very stable formulations of submicron oil-in-water emulsions from Adenanthera pavonina L. (family Leguminosae, subfamily Mimosoideae) seed oil, stabilised with soybean lecithin (SPC). Continuing our research, we introduced an additional co-emulsifier, Tween 80, to those formulations in order to decrease the size of the emulsion particles and improve their stability. Formulations with a mean particle size ranging from 43.6 to 306.5 nm and a negative surface charge from -45.3 to -28.5 mV were obtained. Our stability experiments also revealed that most of the tested formulations had a very good degree of stability over a 3-month storage period, both at 4 degrees C and at room temperature. Since many intravenous injectable drugs exhibit lytic activity against erythrocytes, we examined this activity for the emulsion form of cardol, a natural compound with already proven hemolytic properties. The incorporation of this agent into the emulsion caused an evident decrease in hemolytic activity (97-99%). This highly protective effect, observed against sheep erythrocytes, was independent of both the composition and the particle size of the emulsions used. Our studies suggest that nonionic surfactant/phospholipid-based emulsions containing this edible oil of A. pavonina L. may be useful as an alternative formulation matrix for pharmaceutical, nutritional or cosmetic applications of otherwise membrane-acting components.
Subject(s)
Fabaceae/chemistry , Hemolysis/drug effects , Plant Oils/chemistry , Plant Oils/pharmacology , Protective Agents/pharmacology , Seeds/chemistry , Animals , Emulsions , Erythrocytes/drug effects , Particle Size , Protective Agents/chemistry , Sheep , TemperatureABSTRACT
The oil of Adenanthera pavonina L. seeds was analysed by chromatographic and instrumental means. The oil was found to be rich in neutral lipids (86.2%), and low in polar lipids (13.8%). The neutral lipids consisted mainly of triacylglycerols (64.2%). Unsaturated fatty acids were found as high as 71%, while the percentage of saturated fatty acids was only 29%. GC and GC/MS analyses revealed linoleic, oleic and lignocerotic acid to be predominant among all fatty acids in the A. pavonina oil, whereas stigmasterol was the major steroid identified within this study. Subsequently, the oil was used for preparation of submicron oil-in-water (o/w) lipid emulsions. Lipid emulsions were formulated by using soybean lecithin (SL) to investigate their particle size, Zeta potential and stability at the different oil and SL ratios. The results obtained indicate possible applications of the tested oil in pharmaceutical and medical fields as drug and cosmetic active ingredient carriers.