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21 result(s) for "Schelz, Zsuzsanna"
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Ginger and Its Purified Major Components Inhibit Clinically Relevant Uptake and Efflux Transporters In Vitro
Background/Objectives: Ginger (Zingiber officinale Roscoe) is a flowering plant widely used as a spice and natural medicine for millennia. Ginger demonstrates multiple protective effects, regulates cholesterol, and may reduce the risk of cancer and colitis. However, little attention has been paid to its potential to cause herb–drug interactions (HDIs). The aim of this study was to investigate the interaction of ginger extract and its major components [6]-gingerol and [6]-shogaol with clinically relevant uptake and efflux transporters in vitro. Methods: Transporter-overexpressing cell lines of 25 uptake transporters and inside-out membrane vesicles containing 8 efflux transporters were employed to measure potential interactions. Results: Zingiber officinale extract at 150 µg/mL interacted with 17 of 33 transporters examined. These were further investigated for interactions with the purified active components. Seven and 16 transporters interacted with pure [6]-gingerol (100 µM) and [6]-shogaol (100 µM), respectively. To evaluate the risk of in vivo inhibition, IC50 values were determined for the affected transporters. Based on standard risk assessment calculations, we confirmed previously reported inhibitory effects of ginger components on MDR1 (67.64 µM) and BCRP (9.931 µM), and revealed novel potential interactions with renal OAT3 (0.956 µM) and URAT1 (5.887 µM), hepatic OCT1 (4.287 µM) and BSEP (25.45 µM), and the ubiquitously expressed ENT1 (11.62 µM) ([6]-shogaol IC50 values are shown in parentheses). Strong and isoform-selective inhibition of OAT3 by [6]-shogaol is particularly intriguing. Additionally, via cell viability experiments on a set of human cervical, breast, and oropharyngeal cancer cell lines, we demonstrated the antiproliferative effect of [6]-shogaol in vitro. Conclusions: Prolonged consumption of high-dose ginger supplements may pose a risk of transporter-mediated HDIs when consumed concomitantly with conventional medications. Our study encourages follow-up of the suspected effects in vivo.
Stereoselective Synthesis and Antiproliferative Activity of Steviol-Based Diterpene 1,3-Aminoalcohol Regioisomers
A series of novel diterpene-type 1,3-aminoalcohols and their regioisomers have been synthesised from natural stevioside in a stereoselective manner. The key intermediate β-keto alcohol was prepared using Wagner–Meerwein rearrangement of the epoxide derived from steviol methyl ester. The primary aminoalcohol was formed via Raney-nickel-catalysed hydrogenation of an oxime, and a versatile library of aminoalcohols was synthesised using a Schiff base with the primary amines. The aminoalcohol regioisomers were prepared from the mesylate of the β-keto alcohols. The corresponding primary aminoalcohol was formed via the palladium-catalysed hydrogenation of hydroxyl-azide, and click reactions of the latter were also carried out. The new compounds were characterised using 1D- and 2D-NMR techniques and HRMS measurements. The in vitro investigations showed high inhibition of cell growth in human cancer cell lines (HeLa, SiHa, A2780, MCF-7 and MDA-MB-231) in the case of naphthalic N-substituted derivatives. The antiproliferative effects were assayed using the MTT method.
In Vitro Investigation of the Antiproliferative and Antimetastatic Effects of Atorvastatin: A Focus on Cervical and Head and Neck Cancers
Background/Objectives: In spite of substantial treatment progress, cancer persists as a leading health challenge. With the slow advancement in developing new anticancer agents, drug repurposing provides a promising strategy to enhance cancer therapy. This study investigates the antiproliferative and antimetastatic properties of two 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, atorvastatin and rosuvastatin, which represent lipophilic and hydrophilic statins, respectively. Methods: Growth inhibition was evaluated in a panel of human cancer cells using the standard MTT assay. Apoptotic effects were determined through flow cytometry, caspase-3 activity assay, mitochondrial membrane potential assessment, and Hoechst/Propidium iodide fluorescent double staining. Migration and invasion assays were conducted using wound-healing and Boyden chamber assays, respectively. Results: Atorvastatin demonstrated more pronounced growth-inhibitory effects than rosuvastatin, with the IC50 values in the range of 2.57–61.01 µM. Atorvastatin exhibited both biochemical and morphological indicators of apoptosis. Flow cytometry revealed cell cycle disruptions and increased sub-G1 apoptotic populations in HPV-positive oral squamous carcinoma cells (UPCI-SCC-154) and HPV-negative cervical cancer cells (C33A). Atorvastatin also significantly inhibited cell migration and invasion in the tested cell lines. Conclusions: Our results highlight the promising anticancer potential of atorvastatin in cervical cancer and oral squamous carcinoma cells. However, these findings are limited to in vitro models and warrant further in vivo validation.
Antimicrobial, Multidrug Resistance Reversal and Biofilm Formation Inhibitory Effect of Origanum majorana Extracts, Essential Oil and Monoterpenes
Origanum majorana L. is a widely used medicinal plant; its distilled oil and preparations are extensively utilised in the phytotherapy and food industries. The objective of this study is to evaluate the extracts and the essential oil (EO) of Origanum majorana L, and its monoterpenes for antimicrobial, bacterial multidrug resistance reversing, and biofilm formation inhibitory potency. The composition of EO and n-hexane extract was characterized by GC-MS. In the essential oil terpinen-4-ol (24.92%), trans-sabinene hydrate (25.18%), γ-terpinene (6.48%), cis-sabinene hydrate (5.44%), p-cymene (4.72%), sabinene (4.53%), α-terpineol (4.43%), and α-terpinene (3.00%) were found as the main constituents while trans-sabinene hydrate (1.43%), and terpinen-4-ol (0.19%) were detected in the n-hexane extract besides a series of hydrocarbons. The antibacterial activity of EO and terpinen-4-ol, α-terpinene, and linalool was also assessed against sensitive and drug-resistant S. aureus, and E. coli strains with MIC values of 0.125–0.250% and 30–61 µM, respectively. In the efflux pump (EP) inhibitory assay, made by the ethidium bromide accumulation method in E. coli ATCC 25922, and AG100 and S. aureus ATCC 25923, and MRSA ATCC 43300 strains, EO exhibited substantial activity, especially in the E. coli ATCC 25922 strain. Among the EO constituents, only sabinene was an EP inhibitor in sensitive Escherichia strain. In the case of S. aureus strains, EO and sabinene hydrate exhibited moderate potency on the drug-resistant phenotype. The antibiofilm effects of the samples were tested by crystal violet staining at sub-MIC concentration. γ-Terpinene, terpinen-4-ol, sabinene, sabinene hydrate and linalool were found to be effective inhibitors of biofilm formation (inhibition 36–86%) on E. coli ATCC 25922 and S. aureus MRSA ATCC 43300, while EO was ineffective on these strains. In contrast to this, biofilms formed by E. coli AG100 and S. aureus ATCC 25923 were significantly inhibited by the EO; however, it was not affected by any of the monoterpenes. This observation suggests that the antibiofilm effect might be altered by the synergism between the components of the essential oil.
Development, in vitro and ex vivo characterization of lamotrigine-loaded bovine serum albumin nanoparticles using QbD approach
The present study aimed to prepare and optimize lamotrigine-loaded bovine serum albumin nanoparticles (LAM-NP) using the Quality by Design (QbD) approach and to investigate both the and effects of different cross-linking agents glutaraldehyde (GLUT), glucose (GLUC) and 1-(3-dimethylaminutesopropyl)-3-ethylcarbodiimide hydrochloride (EDC) on intranasal applicability. Cross-linked LAM-NP from EDC (NP-EDC-1) showed the lowest Z-average value (163.7 ± 1.9 nm) and drug encapsulation efficacy (EE%) of 97.31 ± 0.17%. The drug release of GLUC cross-linked LAM-NP (NP-GLUC-9), glutaraldehyde cross-linked LAM-NP (NP-GLUT-2), and NP-EDC-1 at blood circulation conditions was higher than the initial LAM. The results of the blood-brain barrier parallel artificial membrane permeability assay (BBB-PAMPA) showed an increase in the permeability of LAM through the BBB with NP-GLUC-9 and an increase in flux with all selected formulations. The study showed that LAM diffusion from the selected formulations through the human nasal mucosa was higher than in case of initial LAM. The cytotoxicity study indicated that BSA-NP reduced LAM toxicity, and GLUC 9 mM and EDC 1 mg could be alternative cross-linking agents to avoid GLUT 2% v/v toxicity. Furthermore, permeability through Caco-2 cells showed that nasal epithelial transport/absorption of LAM was improved by using BSA-NPs. The use of BSA-NP may be a promising approach to enhance the solubility, permeability through BBB and decrease the frequency of dosing and adverse effects of LAM.
Repositioning of HMG-CoA Reductase Inhibitors as Adjuvants in the Modulation of Efflux Pump-Mediated Bacterial and Tumor Resistance
Efflux pump (EP)-mediated multidrug resistance (MDR) seems ubiquitous in bacterial infections and neoplastic diseases. The diversity and lack of specificity of these efflux mechanisms raise a great obstacle in developing drugs that modulate efflux pumps. Since developing novel chemotherapeutic drugs requires large investments, drug repurposing offers a new approach that can provide alternatives as adjuvants in treating resistant microbial infections and progressive cancerous diseases. Hydroxy-methyl-glutaryl coenzyme-A (HMG-CoA) reductase inhibitors, also known as statins, are promising agents in this respect. Originally, statins were used in the therapy of dyslipidemia and for the prevention of cardiovascular diseases; however, extensive research has recently been performed to elucidate the functions of statins in bacterial infections and cancers. The mevalonate pathway is essential in the posttranslational modification of proteins related to vital eukaryotic cell functions. In this article, a comparative review is given about the possible role of HMG-CoA reductase inhibitors in managing diseases of bacterial and neoplastic origin. Molecular research and clinical studies have proven the justification of statins in this field. Further well-designed clinical trials are urged to clarify the significance of the contribution of statins to the lower risk of disease progression in bacterial infections and cancerous diseases.
CuAAC-Based Synthesis, Copper-Catalyzed Aldehyde-Forming Hydrolytic Fission and Antiproliferative Evaluation of Novel Ferrocenoylamino-Substituted Triazole-Tethered Quinine–Chalcone Hybrids
A series of novel triazole-tethered ferrocenoylamino-substituted cinchona–chalcone hybrids along with two representative benzoylamino-substituted reference compounds were prepared by three methods of CuAAC chemistry. In line with the limited success or complete failure of attempted conversions with low catalyst loadings, by means of DFT modeling studies, we demonstrated that a substantial part of the Cu(I) ions can be chelated and thus trapped in the aroylamino-substituted cinchona fragment and all of the accessible coordinating sites of the chalcone residues. Accordingly, increased amounts of catalysts were used to achieve acceptable yields; however, the cycloadditions with para-azidochalcones were accompanied by partial or complete aldehyde-forming hydrolytic fission of the enone C=C bond in a substituent-, solvent- and copper load-dependent manner. The experienced hydrolytic stability of the hybrids obtained by cycloadditions with ortho-azidochalcones was interpreted in terms of relative energetics, DFT reactivity indices and MO analysis of simplified models of two isomer copper–enone complexes. The novel hybrids were evaluated on HeLa, MDA-MB-231 and A2780 cell lines and showed substantial activity at low-to-submicromolar concentrations. An organometallic model carrying 3,4,5-trimethoxyphenyl residue in the enone part with a para-disubstituted benzene ring in the central skeletal region was identified as the most potent antiproliferative lead, characterized by submicromolar IC50 values measured on the three investigated cells. The biological assays also disclosed that this ferrocenoylamino-containing lead compound displays a ca. two- to five-fold more substantial antiproliferative effect than its benzoylamino-substituted counterpart.
Development of Lomustine and n-Propyl Gallate Co-Encapsulated Liposomes for Targeting Glioblastoma Multiforme via Intranasal Administration
This work aimed to develop lomustine (LOM) and n-propyl gallate (PG)-loaded liposomes suitable for targeting glioblastoma multiforme (GBM) via the auspicious nose-to-brain drug delivery pathway. The therapeutical effect of LOM, as a nitrosourea compound, can be potentiated by PG suitable for enhanced anti-cancer therapy. Nose-to-brain delivery of PG and LOM combined in liposomes can overcome the poor water solubility, absorption properties, and toxicity issues in the systemic circulation. Optimization and characterization of the liposomal carrier with binary drug contents were carried out in order to achieve adequate encapsulation efficiency, loading capacity, drug release, and ex vivo permeation. The optimized liposome co-encapsulated with both drugs showed suitable Z-average (127 ± 6.9 nm), size distribution (polydispersity index of 0.142 ± 0.009), zeta potential (−34 ± 1.7 mV), and high encapsulation efficacy (63.57 ± 1.3% of PG and 73.45 ± 2.2% of LOM, respectively) meeting the acceptance criteria of nose-to-brain transport for both drugs. MTT assays of PG-LOM formulations were also conducted on NIH/3T3 (murine embryonic fibroblast), U87 (glioblastoma), and A2780 (ovarian cancer) cell lines indicating reduced an antiproliferative effect on all types of cells. Our results supported the use of this novel combination of LOM and PG in a liposomal formulation as a promising carrier for glioblastoma targeting via the intranasal route.
Isolation and NMR Scaling Factors for the Structure Determination of Lobatolide H, a Flexible Sesquiterpene from Neurolaena lobata
A new flexible germacranolide (1, lobatolide H) was isolated from the aerial parts of Neurolaena lobata. The structure elucidation was performed by classical NMR experiments and DFT NMR calculations. Altogether, 80 theoretical level combinations with existing 13C NMR scaling factors were tested, and the best performing ones were applied on 1. 1H and 13C NMR scaling factors were also developed for two combinations utilizing known exomethylene containing derivatives, and the results were complemented by homonuclear coupling constant (JHH) and TDDFT-ECD calculations to elucidate the stereochemistry of 1. Lobatolide H possessed remarkable antiproliferative activity against human cervical tumor cell lines with different HPV status (SiHa and C33A), induced cell cycle disturbance and exhibited a substantial antimigratory effect in SiHa cells.
Modulation of Multispecific Transporters by Uncaria tomentosa Extract and Its Major Phytoconstituents
Background/Objectives: One of the major risks associated with the concomitant use of herbal products and therapeutic drugs is herb–drug interactions (HDIs). The most common mechanism leading to HDIs is the inhibition and/or induction of transport proteins and drug-metabolizing enzymes by herbal ingredients, causing changes in the pharmacokinetic disposition of the victim drug. The present study aimed to determine the potential interactions of Uncaria tomentosa (UT) (cat’s claw), a popular herb due to its supposed health benefits. Methods: The effect of UT extract and its major oxindole alkaloids was investigated on multispecific solute carrier (SLC) and ATP-binding cassette (ABC) drug transporters, using SLC transporter-overexpressing cell lines and vesicles prepared from ABC transporter-overexpressing cells. Results: UT extract significantly inhibited all ABC transporters and the majority of the SLC transporters tested. Of the investigated oxindole alkaloids, isopteropodine significantly inhibited OATP, OCT1 and OCT2, OAT3, ENT4, MDR1, and BCRP transporters. OCTs, OCTN1-, ENT1-, and MDR1-mediated substrate accumulation was below 50% in the presence of mitraphylline. Conclusions: Based on the calculated intestinal concentration of UT extract, interactions with intestinal transporters, especially OATP2B1, ENTs, MRP1, MRP2, MDR1, and BCRP could be relevant in vivo. Our data can help to predict the clinical consequences of UT co-administration with drugs, such as increased toxicity or altered efficacy. In conclusion, the use of these in vitro models is applicable for the analysis of transporter-mediated HDIs similar to drug–drug interaction (DDI) prediction.