Preparation of Ergosterol-Loaded Nanostructured Lipid Carriers for Enhancing Oral Bioavailability and Antidiabetic Nephropathy Effects.

In our previously studies, we confirmed that ergosterol could ameliorate diabetic nephropathy by suppressing the proliferation of mesangial cells and the accumulation of extracellular matrix (ECM). However, the therapeutic application of ergosterol may be confined due to poor aqueous solubility and low oral bioavailability. We aim to prepare ergosterol-loaded nanostructured lipid carriers (ERG-NLCs) to enhance the solubility and oral bioavailability of ergosterol. ERG-NLCs were prepared using glyceryl monostearate and decanoyl/octanoyl-glycerides by hot emulsification-ultrasonication method and characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) analysis, entrapment efficiency (EE), and drug loading (DL) capacity studies. The prepared ERG-NLCs were spherical, with particle size of 81.39 nm and negative zeta potential of 30.77 mV. Ergosterol was successfully encapsulated in NLCs with a high EE of 92.95% and a DL capacity of 6.51%. In pharmacokinetic study, Cmax and AUC0-∞ of ergosterol in ERG-NLCs were obviously enhanced, and the relative oral bioavailability of ERG-NLCs was 277.56% higher than that of raw ergosterol. Moreover, the in vitro pharmacodynamic study indicated that ERG-NLCs inhibited high-glucose-stimulated mesangial cells over proliferation and ECM accumulation more effectively compared to raw ergosterol. In conclusion, the validated ERG-NLCs showed that NLCs mediated delivery could be used as potential vehicle to enhance solubility, oral bioavailability and therapeutic efficacy of ergosterol.

Efficacy of curcumin in the treatment of experimental vulvovaginal candidiasis / Eficacia de la curcumina en el tratamiento de la candidiasis vulvovaginal experimental

Background: Candida albicans is the main agent that causes vulvovaginal candidiasis. Resistance among isolates to azole antifungal agents has been reported. Aims: Due to the well-known antifungal potential of curcumin, the purpose of this work was to evaluate the in vitro anticandidal activity of curcumin and its effect in the treatment of experimental vulvovaginal candidiasis. Methods: The anticandidal activity of curcumin was investigated against eight Candida strains by the broth microdilution assay, and its mechanism of action was evaluated by testing the binding to ergosterol. Then, the effect of curcumin in the treatment of vulvovaginal candidiasis was evaluated in an immunosuppressed, estrogen treated rat model. Results: Curcumin showed minimum inhibitory concentration values of 125-1000μg/ml, and the best result was observed against Candida glabrata. The compound was shown to be able to bind to the ergosterol present in the membrane, event that may be the mechanism of action. In addition, in the in vivo model of vulvovaginal candidiasis with C. albicans, treatments reduced the vaginal fungal burden in infected rats after seven days of treatment with different doses. Conclusions: Curcumin could be considered a promising effective antifungal agent in the treatment of vulvovaginal candidiasis

Antecedentes: Candida albicans es la principal causante de la candidiasis vulvovaginal y algunos aislamientos pueden presentar resistencia a los antifúngicos azólicos. Objetivos: Debido al conocido potencial antifúngico de la curcumina, el objetivo de este trabajo fue evaluar su actividad anti-Candidain vitro y su efecto en el tratamiento de la candidiasis vulvovaginal experimental. Métodos: La actividad anti-Candida de la curcumina se evaluó frente a ocho cepas de Candida mediante un ensayo de microdilución en caldo, y su mecanismo de acción se estudió por una prueba de unión a ergosterol. Posteriormente se evaluó el efecto de la curcumina en el tratamiento de la candidiasis vulvovaginal con un modelo de rata inmunosuprimida, tratada con estrógenos. Resultados: La curcumina mostró valores de concentración inhibitoria mínima de 125-1.000μg/ml, y el mejor resultado se observó frente a Candida glabrata. El compuesto demostró ser capaz de unirse al ergosterol de la membrana, lo que podría ser su mecanismo de acción. Además, en el modelo in vivo de candidiasis vulvovaginal con C. albicans, los tratamientos redujeron la carga fúngica vaginal en ratas infectadas después de siete días de tratamiento con diferentes dosis. Conclusiones: La curcumina podría considerarse un agente antifúngico eficaz prometedor en el tratamiento de la candidiasis vulvovaginal

Ergosterol-loaded poly(lactide-co-glycolide) nanoparticles with enhanced in vitro antitumor activity and oral bioavailability.

AIM: Ergosterol is a plant sterol with anti-tumor and anti-angiogenic activities, but is poorly soluble. In this study, we attempted to enhance its anti-tumor action and oral bioavailability via poly(lactide-co-glycolide) (PLGA) nanoparticle encapsulation. METHODS: Ergosterol-loaded PLGA nanoparticles (NPs/Erg) were prepared using the emulsion/solvent evaporation technique. Their physicochemical properties were characterized, and their cytotoxicity against human cancer cell lines was evaluated with MTT assay. The pharmacokinetics and tissue distribution of NPs/Erg were investigated in rats and mice, respectively. RESULTS: NPs/Erg were spherical in shape with a particle size of 156.9±4.8 nm and a Zeta potential of -19.27±1.13 mV, and had acceptable encapsulation efficiency and loading capacity. NPs/Erg exerted much stronger cytotoxicity against human cancer cells than the free ergosterol, and showed significantly reduced IC50 values (14.69±0.48 µg/mL in glioma U251 cells; 9.43±0.52 µg/mL in breast cancer MCF-7 cells; 4.70±0.41 µg/mL in hepatoma HepG2 cells). After oral administration of a single dose in rats, NPs/Erg displayed a prolonged plasma circulation with a 4.9-fold increase of oral bioavailability compared with the free ergosterol. After mice received NPs/Erg, the ergosterol in NPs/Erg was rapidly distributed in stomach, kidneys, liver, brain, spleen, and virtually non-existent in heart and lungs. The presence of NPs/Erg in brain was particularly improved compared with the free ergosterol. CONCLUSION: The PLGA nanoparticles serve as a promising carrier for the poorly soluble ergosterol and significantly improve its bioavailability, biodistribution and in vitro anti-tumor activities.

Metabolites identification and multi-component pharmacokinetics of ergostane and lanostane triterpenoids in the anticancer mushroom Antrodia cinnamomea.

Antrodia cinnamomea is a precious medicinal mushroom popularly used for adjuvant cancer therapy in Taiwan. Its major bioactive constituents are ergostane and lanostane triterpenoids. Although clinical trials for A. cinnamomea have been recently initiated, its metabolism remains unclear. The present study aims to elucidate the metabolism and pharmacokinetics of A. cinnamomea in rats. After oral administration of an ethanol extract, 18 triterpenoids and 8 biotransformed metabolites were detected in rats plasma by UHPLC/qTOF-MS. Four of the metabolites were prepared by semi-synthesis and fully identified by NMR, while the others were tentatively characterized by comparing with the metabolites of single compounds (antcins B, C, H and K). Furthermore, a multi-component pharmacokinetic study of A. cinnamomea was carried out to monitor the plasma concentrations of 14 triterpenoids (ergostanes 1-3, 5-8, 14-16; lanostanes 9, 10, 17, 19) and 2 metabolites (M5, M6) by LC/MS/MS in rats after oral administration of the ethanol extract (1.0 g/kg). The results showed that ergostanes and Δ(7,9(11)) lanostanes, but not Δ(8) lanostanes, could get into circulation. The low-polarity ergostanes (antcins B and C) undertook hydrogenation (C-3 or C-7 carbonyl groups) or hydroxylation to produce polar metabolites. High-polarity ergostanes (antcins H and K) and Δ(7,9(11)) lanostanes were metabolically stable. We also discovered that ergostanes and lanostanes showed remarkably different pharmacokinetic patterns. The ergostanes were generally absorbed and eliminated rapidly, whereas the lanostanes remained in the plasma at a low concentration for a relatively long time. The results indicate that high-polarity ergostanes are the major plasma-exposed components of A. cinnamomea, and may play an important role in its therapeutic effects.

Simultaneous HPLC determination of ergosterol and 22,23-dihydroergosterol in Flammulina velutipes sterol-loaded microemulsion.

An efficient HPLC method was developed and validated for the simultaneous determination of ergosterol and 22,23-dihydroergosterol in Flammulina velutipes sterol-loaded microemulsions (FVSMs). The different chromatographic conditions for in vitro and in vivo determinations were investigated, with the application examined by tissue distribution. Chromatographic separation was achieved on an Inertsil ODS-SP (250 × 4.6 mm, 5 µm) analytical column using a mobile phase of 98% methanol (in vitro), and 93% methanol for stomach samples and 96% methanol for other samples (in vivo) at 1.0 mL/min. The sterol content was detected at 282 nm. The established in vitro linearity ranges for ergosterol and 22,23-dihydroergosterol were 0.58-72.77 µg/mL (r1 = 0.9999) and 0.59-73.25 µg/mL (r2 = 0.9999), respectively, with the biological (in vivo) samples following the same trend. The accuracy of the method was >99% (in vitro) and between 93%-108% (in vivo). The LOQ was 2.15 µg/L for ergosterol and 2.41 µg/L for 22,23-dihydroergosterol in the in vitro studies. Also, the precisions met the acceptance criterion. These results indicate that the established HPLC method was specific, linear, accurate, precise and sensitive for the separation and simultaneous determination of ergosterol and 22,23-dihydroergosterol.

Ultra performance liquid chromatography coupled with electrospray and atmospheric pressure chemical ionization (ESCi)-quadrupole time-of-flight mass spectrometry with novel mass spectrometry(Elevated Energy) (MS(E)) data collection technique: determination and pharmacokinetics, tissue distribution and biliary excretion study of ergone in rat.

Ergosta-4,6,8(14),22-tetraen-3-one (ergone) has been proved to have novel antitumor effects on HepG2 cells. The aim of this study was to investigate the pharmacokinetics, tissue distribution, and biliary excretion of ergone in rats following a single oral administration (5, 10, and 20 mg/kg). The levels of ergone in plasma, tissues, and bile were measured by ultra performance liquid chromatography coupled with electrospray and atmospheric pressure chemical ionization (ESCi)-quadrupole time-of-flight mass spectrometry with novel mass spectrometry(Elevated Energy) (MS(E)) data collection technique method. The results show ergone was distributed and eliminated from rat plasma and in non-linear pharmacokinetics from a dose range of 5-20 mg/kg. The ergone was found to distribute widely in the internal organs, with tissue concentrations in order of lungs, spleen, liver, intestine, kidneys, heart, stomach, parorchis, teasticles, and brain. At 12 h after dosing, the tissue concentrations in the organs were markedly decreased. The lungs, spleen, and liver were the dominant organs with high tissue concentrations that might be the primary sites for metabolism and elimination of ergone. Total recoveries of ergone within 24 h in bile were 34.14%.

Pharmacokinetics of ergosterol in rats using rapid resolution liquid chromatography-atmospheric pressure chemical ionization multi-stage tandem mass spectrometry and rapid resolution liquid chromatography/tandem mass spectrometry.

Rapid resolution liquid chromatography/tandem multi-stage mass spectrometry (RRLC-MS(n)) and rapid resolution liquid chromatography/tandem mass spectrometry (RRLC/MS/MS) methods were developed for the identification and quantification of ergosterol and its metabolites from rat plasma, urine and faeces. Two metabolites (ERG1 and ERG2) were identified by RRLC/MS(n). The concentrations of the ergosterol were determined by RRLC/MS/MS. The separation was performed on an Agilent Zorbax SB-C18 with the mobile phase consisting of methanol and water (containing 0.1% formic acid). The detection was carried out by means of atmospheric pressure chemical ionization mass spectrometry in positive ion mode with multiple reaction monitoring (MRM). Linear calibration curves were obtained in the concentration range of 7-2000, 6-2000 and 8-7500 ng/mL for plasma, urine and faecal homogenate, respectively. The intra- and inter-day precision values (RSD) were below 10%. The method was applied to the pharmacokinetic properties and elimination pathway of ergosterol in rats.

A fast and sensitive HPLC-MS/MS analysis and preliminary pharmacokinetic characterization of ergone in rats.

A fast and sensitive HPLC-APCI-MS/MS method was developed for the determination of ergosta-4,6,8(14),22-tetraen-3-one (ergone) in rat plasma. The plasma sample containing ergone and ergosterol (internal standard) were simply treated with acetone to precipitate and remove proteins and the isolated supernatants were directly injected into the HPLC-APCI-MS/MS system. Chromatographic separation was performed on a 1.8microm Zorbax SB-C18 column (100mm x 3.0mm) with a 97:3 (v/v) mixed solution of methanol and 0.1% aqueous formic acid being used as mobile phase. Quantification was performed by multiple selected reactions monitoring (MRM) of the transitions with (m/z)(+) 393-268 for ergone and (m/z)(+) 379-69 for the IS. The method was validated in the concentration range of 5-1600ng/mL for ergone. The precision of the assay (RSD%) was less than 10.5% at all concentrations levels within the tested range and adequate accuracy, and the limit of detection was 1.5ng/mL. The absolute recoveries of both ergone and ergosterol from the plasma were more than 95%. The developed method has been successfully applied to the pharmacokinetic study of the drug in SD rats.

Effects of cholesterol depletion and increased lipid unsaturation on the properties of endocytic membranes.

Lipid analogs with dialkylindocarbocyanine (DiI) head groups and short or unsaturated hydrocarbon chains (e.g. DiIC(12) and FAST DiI) enter the endocytic recycling compartment efficiently, whereas lipid analogs with long, saturated tails (e.g. DiIC(16) and DiIC(18)) are sorted out of this pathway and targeted to the late endosomes/lysosomes (Mukherjee, S., Soe, T. T., and Maxfield, F. R. (1999) J. Cell Biol. 144, 1271-1284). This differential trafficking of lipid analogs with the same polar head group was interpreted to result from differential partitioning to different types of domains with varying membrane order and/or curvature. Here we investigate the system further by monitoring the trafficking behavior of these lipid analogs under conditions that alter domain properties. There was a marked effect of cholesterol depletion on the cell-surface distribution and degree of internalization of the lipid probes. Furthermore, instead of going to the late endosomes/lysosomes as in control cells, long chain DiI analogs, such as DiIC(16), were sorted to the recycling pathway in cholesterol-depleted cells. We confirmed that this difference was due to a change in overall membrane properties, and not cholesterol levels per se, by utilizing a Chinese hamster ovary cell line that overexpressed transfected stearoyl-CoA desaturase 1, a rate-limiting enzyme in the production of monounsaturated fatty acids. These cells have a decrease in membrane order because they contain a much larger fraction of unsaturated fatty acids. These cells showed alteration of DiI trafficking very similar to cholesterol-depleted cells. By using cold Triton X-100 extractability of different lipids as a criterion to determine the membrane properties of intracellular organelles, we found that the endocytic recycling compartment has abundant detergent-resistant membranes, in contrast to the late endosomes and lysosomes.

Distribution and transport of cholesterol in Caenorhabditis elegans.

Cholesterol transport is an essential process in all multicellular organisms. In this study we applied two recently developed approaches to investigate the distribution and molecular mechanisms of cholesterol transport in Caenorhabditis elegans. The distribution of cholesterol in living worms was studied by imaging its fluorescent analog, dehydroergosterol, which we applied to the animals by feeding. Dehydroergosterol accumulates primarily in the pharynx, nerve ring, excretory gland cell, and gut of L1-L3 larvae. Later, the bulk of dehydroergosterol accumulates in oocytes and spermatozoa. Males display exceptionally strong labeling of spermatids, which suggests a possible role for cholesterol in sperm development. In a complementary approach, we used a photoactivatable cholesterol analog to identify cholesterol-binding proteins in C. elegans. Three major and several minor proteins were found specifically cross-linked to photocholesterol after UV irradiation. The major proteins were identified as vitellogenins. rme-2 mutants, which lack the vitellogenin receptor, fail to accumulate dehydroergosterol in oocytes and embryos and instead accumulate dehydroergosterol in the body cavity along with vitellogenin. Thus, uptake of cholesterol by C. elegans oocytes occurs via an endocytotic pathway involving yolk proteins. The pathway is a likely evolutionary ancestor of mammalian cholesterol transport.

Metabolism of orally administered ergosterol and 7-dehydrocholesterol in rats and lack of evidence for their vitamin D biological activity.

Metabolism of orally administered ergosterol (Erg) and 7-dehydrocholesterol (7-DHC) in rats and their vitamin D biological activity were investigated. Most of orally administered Erg and 7-DHC were excreted in feces and the remaining sterols were absorbed through intestine. The absorbed sterols were not transported in skin as the intact forms but metabolized into brassicasterol and cholesterol, respectively, within 25 h. Neither increment of intestinal calcium absorption nor plasma calcium concentrations were observed by oral administration of Erg and 7-DHC to vitamin D-deficient rats. Therefore, we have concluded that orally administered Erg and 7-DHC have no vitamin D biological activity.

[Substrate specificity of the biotransformation enzymes in a Nocardia erythropolis culture]. / Izuchenie substratnoi spetsifichnosti fermentov biotransformatsii kul'tury Nocardia erthropolis.

Substrate specificity of biotransformation enzymes of culture Nocardia erythropolis was studied. Products of transformation of cholesterol and three sterols of microbial origin: ergosterol, ergosta-5,7-dien-3 beta-ol and ergosta-7,22-dien-3 beta-ol was identified with a help of thin-layer chromatography, UV spectrophotometry and mass-spectrometry. It was established, that delta 22-bond in the side chains of sterols and delta 7-bond slows and delta 5-bond makes impossible cleavage of side chains of sterols.

[Analysis of the products of ergosta-7,22-dien-3-beta-ol biotransformation by a Nocardia erythropolis culture]. / Analiz produktov biotransformatsii érgosta-7,22-dien-3-beta-ola kul'turoi Nocardia erythropolis.

The products of biotransformation by Nocardia erythropolis-402 of the microbial sterol ergosta-7,22-dien-3 beta-ol isolated from a Saccharomyces cerevisiae mutant were studied. The products were identified as ergosta-7,22-dien-3-one and ergosta-7,22-dien-17 alpha-ol-3-one by thin-layer chromatography, UV-spectrophotometry and mass-spectroscopy. It was found that the existence of 7-8 double bond slowed down the cleavage of the sterol side chain. The absence of 5-6 double bond prevents the formation of delta 4-3-ketosystem of coupled bonds.