- Tumor microenvironment-targeted poly-L-glutamic acid-based combination conjugate for enhanced triple negative breast cancer treatment. [Journal Article]
- BBiomaterials 2018; 186:8-21
- The intrinsic characteristics of the tumor microenvironment (TME), including acidic pH and overexpression of hydrolytic enzymes, offer an exciting opportunity for the rational design of TME-drug deli...
The intrinsic characteristics of the tumor microenvironment (TME), including acidic pH and overexpression of hydrolytic enzymes, offer an exciting opportunity for the rational design of TME-drug delivery systems (DDS). We developed and characterized a pH-responsive biodegradable poly-L-glutamic acid (PGA)-based combination conjugate family with the aim of optimizing anticancer effects. We obtained combination conjugates bearing Doxorubicin (Dox) and aminoglutethimide (AGM) with two Dox loadings and two different hydrazone pH-sensitive linkers that promote the specific release of Dox from the polymeric backbone within the TME. Low Dox loading coupled with a short hydrazone linker yielded optimal effects on primary tumor growth, lung metastasis (∼90% reduction), and toxicological profile in a preclinical metastatic triple-negative breast cancer (TNBC) murine model. The use of transcriptomic analysis helped us to identify the molecular mechanisms responsible for such results including a differential immunomodulation and cell death pathways among the conjugates. This data highlights the advantages of targeting the TME, the therapeutic value of polymer-based combination approaches, and the utility of -omics-based analysis to accelerate anticancer DDS.
- Synthetic isoflavones and doping: A novel class of aromatase inhibitors? [Journal Article]
- DTDrug Test Anal 2018 Aug 17
- Anectodical information suggests that flavonoids may be widely used among athletes for their multiple biochemical and pharmacological effects. We have evaluated in vitro the effects of two synthetic ...
Anectodical information suggests that flavonoids may be widely used among athletes for their multiple biochemical and pharmacological effects. We have evaluated in vitro the effects of two synthetic isoflavones, methoxyisoflavone and ipriflavone, on the catalytic activity of human aromatase (CYP19), the enzyme catalyzing the conversion of androgens (ie, testosterone or androstenedione) to estrogens (ie, estradiol and estrone). The potential inhibitory effect was evaluated by measuring the rate of aromatization of testosterone, monitored by gas chromatography-mass spectrometry (GC-MS), both in the presence and in the absence of methoxyisoflavone or ipriflavone, comparing their effects with those of synthetic aromatase inhibitors (formestane, anastrozole, and aminoglutethimide) presently included in the list of prohibited substances and methods, and of natural flavonoids (chrysin, quercetin, and daidzein), that are known inhibitors of CYP19. The preliminary results of our in vitro study show that methoxyisoflavone and ipriflavone act as competitive inhibitors of aromatase, the degree of inhibition measured in vitro being of the same order of magnitude of that of the aromatase inhibitors commonly used in anti-estrogenic therapies. Our preliminary in vitro results indicate that, in principle, a sufficiently large intake of isoflavones could alter the kinetics of the dynamic equilibria between androgens and estrogens, suggesting their monitoring in doping control routine analysis.
- Increased 27-hydroxycholesterol production during luteolysis may mediate the progressive decline in progesterone secretion. [Journal Article]
- MHMol Hum Reprod 2018 01 01; 24(1):2-13
- Does 27-hydroxycholesterol (27OH) actively facilitate the progression of luteolysis?
Does 27-hydroxycholesterol (27OH) actively facilitate the progression of luteolysis?
- Ergostane-Type Sterols from King Trumpet Mushroom (Pleurotus eryngii) and Their Inhibitory Effects on Aromatase. [Journal Article]
- IJInt J Mol Sci 2017 Nov 21; 18(11)
- Two new ergostane-type sterols; (22E)-5α,6α-epoxyergosta-8,14,22-triene-3β,7β-diol (1) and 5α,6α-epoxyergost-8(14)-ene-3β,7α-diol (2) were isolated from the fruiting bodies of king trumpet mushroom (...
Two new ergostane-type sterols; (22E)-5α,6α-epoxyergosta-8,14,22-triene-3β,7β-diol (1) and 5α,6α-epoxyergost-8(14)-ene-3β,7α-diol (2) were isolated from the fruiting bodies of king trumpet mushroom (Pleurotus eryngii), along with eight known compounds (3-10). All isolated compounds were evaluated for their inhibitory effects on aromatase. Among them, 4 and 6 exhibited comparable aromatase inhibitory activities to aminoglutethimide.
- Usefulness of Simultaneous Measurement of Plasma Steroids, Including Precursors, for the Evaluation of Drug Effects on Adrenal Steroidogenesis in Rats. [Journal Article]
- TPToxicol Pathol 2017; 45(6):756-763
- The aim of this study was to evaluate the usefulness of simultaneous measurement of plasma steroids, including precursors, for the evaluation of drug effects on adrenal steroidogenesis in vivo. Plasm...
The aim of this study was to evaluate the usefulness of simultaneous measurement of plasma steroids, including precursors, for the evaluation of drug effects on adrenal steroidogenesis in vivo. Plasma concentrations of corticosterone and its precursors were examined in rats dosed with compounds that affect adrenal steroidogenesis via different modes of action as well as the relationships of the changes with blood chemistry and adrenal histopathology. Male rats were dosed with tricresyl phosphate, aminoglutethimide, trilostane (TRL), metyrapone (MET), ketoconazole (KET), or mifepristone for 7 days. In the TRL, MET, and KET groups, precursor levels were markedly increased, while there were no significant changes in the corticosterone level, suggesting that the precursors are more sensitive biomarkers to detect the effect on adrenal steroidogenesis. Also, the precursors with increased levels were those that are normally metabolized by the inhibited enzymes, reflecting the modes of action of the compounds. In addition, different patterns of changes were observed in blood chemistry and histopathology, supporting the mechanism suggested by the steroid changes. These results show that simultaneous measurement of plasma steroids, including precursors, can be a valuable method to sensitively evaluate drug effects on adrenal steroidogenesis and to investigate the underlying mechanisms.
- Impact of nonsteroidal aromatase inhibitors on steroid profile in a Chinese population. [Randomized Controlled Trial]
- MMedicine (Baltimore) 2017; 96(28):e7411
- Steroid profiling was introduced to determine the endogenous steroid misuse in sports. Thus, screening for the exogenous use of these prohibited substances can be established by monitoring a range of...
Steroid profiling was introduced to determine the endogenous steroid misuse in sports. Thus, screening for the exogenous use of these prohibited substances can be established by monitoring a range of endogenous steroids, which constitute the steroid profile and evaluate their concentrations and ratios against reference values. The steroid profiling is currently based on population statistics. As large interindividual variations exist, athlete biological passport (ABP) analysis is ongoing. This study aimed to identify new biomarker(s) for aromatase inhibitor detection in sports using statistical analysis and adapt the model into ABP analysis.Forty-one Chinese nonathlete volunteers (21 males and 20 females) were administered 3 nonsteroidal aromatase inhibitors (aminoglutethimide, letrozole, and anastrozole) independently. Statistical analysis was performed on 16 steroid profile parameters.After administration, the concentrations of endogenous androgen biomarkers including testosterone (T), epitestosterone, androsterone (AN), etiocholanolone (ETIO), 5α-diol, 5β-diol, and dehydroepiandrosterone were increased, while the level of estrogen was decreased. These biomarkers returned to the baselines levels within 1 month. In females, the concentrations of endogenous biomarkers were affected by nonsteroidal aromatase inhibitors, without a common trend. Three new endogenous biomarkers (AN/estrone, ETIO/estrone, and T/estrone) elevated significantly after treatment. The 3 new models were more sensitive than the World Anti-Doping Agency ratio biomarkers. They were also effective in exponentially weighted moving average chart analysis.Verification experiment demonstrated that the biomarker T/estrone was valid in judging the steroidal aromatase inhibitor abuse. The screening of these new endogenous biomarkers can provide additional parameters to support ABP monitoring and specific information regarding the administered steroids.
- Liver X Receptor α Is Involved in Counteracting Mechanical Allodynia by Inhibiting Neuroinflammation in the Spinal Dorsal Horn. [Journal Article]
- AAnesthesiology 2017; 127(3):534-547
- CONCLUSIONS: Activation of liver X receptor α inhibits mechanical allodynia by inhibiting the activation of glial cells and rebalancing cytokines in the spinal dorsal horn via neurosteroids.
- Aminoglutethimide-induced lysosomal changes in adrenal gland in mice. [Journal Article]
- ETExp Toxicol Pathol 2017 Sep 05; 69(7):424-429
- Aminoglutethimide is a steroidogenesis inhibitor and inhibits a cholesterol side-chain cleavage enzyme (CYP11A1) that converts cholesterol to pregnenolone in mitochondria. We investigated histopathol...
Aminoglutethimide is a steroidogenesis inhibitor and inhibits a cholesterol side-chain cleavage enzyme (CYP11A1) that converts cholesterol to pregnenolone in mitochondria. We investigated histopathological changes induced by 5-day administration of AG in mice. Cytoplasmic vacuoles of various sizes and single cell necrosis were found in zona fasciculata cells in AG-treated mice. Some vacuoles were positive for adipophilin, whereas others were positive for lysosome-associated membrane protein-2 on immunohistochemical staining, indicating they were enlarged lipid droplets and lysosomes, respectively. Electron microscopy revealed enlarged lysosomes containing damaged mitochondria and lamellar bodies in zona fasciculata cells, and they were considered to reflect the intracellular protein degradation processes, mitophagy and lipophagy. From these results, we showed that AG induces excessive lipid accumulation and mitochondrial damage in zona fasciculata cells, which leads to an accelerated lysosomal degradation in mice.
- Preclinical Efficacy and Safety Assessment of Artemisinin-Chemotherapeutic Agent Conjugates for Ovarian Cancer. [Journal Article]
- EEBioMedicine 2016; 14:44-54
- Artemisinin (ARS) and its derivatives, which are clinically used antimalarial agents, have shown antitumor activities. Their therapeutic potencies, however, are limited by their low solubility and po...
Artemisinin (ARS) and its derivatives, which are clinically used antimalarial agents, have shown antitumor activities. Their therapeutic potencies, however, are limited by their low solubility and poor bioavailability. Here, through a pharmacophore hybridization strategy, we synthesized ARS-drug conjugates, in which the marketed chemotherapeutic agents chlorambucil, melphalan, flutamide, aminoglutethimide, and doxifluridine, were separately bonded to Dihydroartemisinin (DHA) through various linkages. Of these, the artemisinin-melphalan conjugate, ARS4, exhibited most toxicity to human ovarian cancer cells but had low cytotoxicity to normal cells. ARS4 inhibited the growth and proliferation of ovarian cancer cells and resulted in S-phase arrest, apoptosis, and inhibition of migration; these effects were stronger than those of its parent drugs, DHA and melphalan. Furthermore, ARS4 modulated the expression of proteins involved in cell cycle progression, apoptosis, and the epithelial-mesenchymal transition (EMT). Moreover, in mice, ARS4 inhibited growth and intraperitoneal dissemination and metastasis of ovarian cancer cells without observable toxic effects. Our results provide a basis for development of the compound as a chemotherapeutic agent.
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- Enantioseparation of racemic aminoglutethimide using asynchronous simulated moving bed chromatography. [Journal Article]
- JCJ Chromatogr A 2016 Oct 07; 1467:347-355
- The separation of aminoglutethimide enantiomers by the continuous multicolumn chromatographic processes were investigated experimentally and theoretically, where the columns were packed with cellulos...
The separation of aminoglutethimide enantiomers by the continuous multicolumn chromatographic processes were investigated experimentally and theoretically, where the columns were packed with cellulose tris 3,5-dimethylphenyl-carbamate stationary phase (brand name Chiralcel OD) and mobile phase was a mixture of n-hexane and ethanol with monoethanolamine additive. The continuous enantioseparation processes included a synchronous shifting process (SMB) and an asynchronous shifting process (VARICOL), which allowed reducing the column number (here from six-column SMB to five-column VARICOL process). Transport-dispersive model with the consideration of both intraparticle mass transfer resistance and axial dispersion was adopted to design and optimize the operation conditions for the separation of aminoglutethimide enantiomers by SMB process and VARICOL process. According to the optimized operation conditions, experiments were carried out on VARICOL-Micro unit using five-column VARICOL process with 1/1.5/1.5/1 configuration and six-column SMB process with 1/2/2/1 configuration. Products of R-aminoglutethimide (R-AG) enantiomer and S-aminoglutethimide (S-AG) enantiomer with more than 99.0% purity were obtained continuously from extract stream and raffinate stream, respectively. Furthermore, the experiemntal data obtained from five-column VARICOL process were compared with that from six-column SMB process, the feasibility and efficiency for the separation of guaifenesin enantiomers by VARICOL processes were evaluated.