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1.
Int J Mol Sci ; 25(10)2024 May 07.
Article in English | MEDLINE | ID: mdl-38791130

ABSTRACT

The increase in multi-drug resistant Candida strains has caused a sharp rise in life-threatening fungal infections in immunosuppressed patients, including those with SARS-CoV-2. Novel antifungal drugs are needed to combat multi-drug-resistant yeasts. This study aimed to synthesize a new series of 2-oxazolines and evaluate the ligands in vitro for the inhibition of six Candida species and in silico for affinity to the CYP51 enzymes (obtained with molecular modeling and protein homology) of the same species. The 5-(1,3-diphenyl-1H-pyrazol-4-yl)-4-tosyl-4,5-dihydrooxazoles 6a-j were synthesized using the Van Leusen reaction between 1,3-diphenyl-4-formylpyrazoles 4a-j and TosMIC 5 in the presence of K2CO3 or KOH without heating, resulting in short reaction times, high compound purity, and high yields. The docking studies revealed good affinity for the active site of the CYP51 enzymes of the Candida species in the following order: 6a-j > 4a-j > fluconazole (the reference drug). The in vitro testing of the compounds against the Candida species showed lower MIC values for 6a-j than 4a-j, and for 4a-j than fluconazole, thus correlating well with the in silico findings. According to growth rescue assays, 6a-j and 4a-j (like fluconazole) inhibit ergosterol synthesis. The in silico toxicity assessment evidenced the safety of compounds 6a-j, which merit further research as possible antifungal drugs.


Subject(s)
Antifungal Agents , Candida , Microbial Sensitivity Tests , Molecular Docking Simulation , Antifungal Agents/pharmacology , Antifungal Agents/chemical synthesis , Antifungal Agents/chemistry , Candida/drug effects , Humans , Oxazoles/chemistry , Oxazoles/pharmacology , Oxazoles/chemical synthesis , Pyrazoles/pharmacology , Pyrazoles/chemistry , Pyrazoles/chemical synthesis , Computer Simulation , SARS-CoV-2/drug effects
2.
Nat Commun ; 15(1): 3927, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38724531

ABSTRACT

Sputum culture reversion after conversion is an indicator of tuberculosis (TB) treatment failure. We analyze data from the endTB multi-country prospective observational cohort (NCT03259269) to estimate the frequency (primary endpoint) among individuals receiving a longer (18-to-20 month) regimen for multidrug- or rifampicin-resistant (MDR/RR) TB who experienced culture conversion. We also conduct Cox proportional hazard regression analyses to identify factors associated with reversion, including comorbidities, previous treatment, cavitary disease at conversion, low body mass index (BMI) at conversion, time to conversion, and number of likely-effective drugs. Of 1,286 patients, 54 (4.2%) experienced reversion, a median of 173 days (97-306) after conversion. Cavitary disease, BMI < 18.5, hepatitis C, prior treatment with second-line drugs, and longer time to initial culture conversion were positively associated with reversion. Reversion was uncommon. Those with cavitary disease, low BMI, hepatitis C, prior treatment with second-line drugs, and in whom culture conversion is delayed may benefit from close monitoring following conversion.


Subject(s)
Antitubercular Agents , Diarylquinolines , Nitroimidazoles , Oxazoles , Sputum , Tuberculosis, Multidrug-Resistant , Humans , Antitubercular Agents/therapeutic use , Antitubercular Agents/pharmacology , Sputum/microbiology , Tuberculosis, Multidrug-Resistant/drug therapy , Tuberculosis, Multidrug-Resistant/microbiology , Diarylquinolines/therapeutic use , Diarylquinolines/pharmacology , Male , Female , Oxazoles/therapeutic use , Adult , Nitroimidazoles/therapeutic use , Nitroimidazoles/pharmacology , Middle Aged , Prospective Studies , Mycobacterium tuberculosis/drug effects , Drug Repositioning
3.
Int J Risk Saf Med ; 35(2): 181-190, 2024.
Article in English | MEDLINE | ID: mdl-38701163

ABSTRACT

BACKGROUND: Delamanid (DLM) is a relatively new drug for drug-resistant tuberculosis (DR-TB) that has been used in Indonesia since 2019 despite its limited safety data. DLM is known to inhibit hERG potassium channel with the potential to cause QT prolongation which eventually leads to Torsades de pointes (TdP). OBJECTIVE: This study aims to analyse the changes of QTc interval in DR-TB patients on DLM regimen compared to shorter treatment regimens (STR). METHODS: A retrospective cohort was implemented on secondary data obtained from two participating hospitals. The QTc interval and the changes in QTc interval from baseline (ΔQTc) were assessed every 4 weeks for 24 weeks. RESULTS: The maximum increased of QTc interval and ΔQTc interval were smaller in the DLM group with mean difference of 18,6 (95%CI 0.3 to 37.5) and 31.6 milliseconds (95%CI 14.1 to 49.1) respectively. The proportion of QTc interval prolongation in DLM group were smaller than STR group (RR=0.62; 95%CI 0.42 to 0.93). CONCLUSION: This study has shown that DLM regimens are less likely to increase QTc interval compared to STR. However, close monitoring of the risk of QT interval prolongation needs to be carried out upon the use of QT interval prolonging antituberculoid drugs.


Subject(s)
Antitubercular Agents , Electrocardiography , Long QT Syndrome , Nitroimidazoles , Oxazoles , Tuberculosis, Multidrug-Resistant , Humans , Retrospective Studies , Male , Female , Tuberculosis, Multidrug-Resistant/drug therapy , Adult , Antitubercular Agents/adverse effects , Antitubercular Agents/administration & dosage , Antitubercular Agents/therapeutic use , Long QT Syndrome/chemically induced , Nitroimidazoles/adverse effects , Nitroimidazoles/therapeutic use , Nitroimidazoles/administration & dosage , Oxazoles/adverse effects , Oxazoles/therapeutic use , Oxazoles/administration & dosage , Middle Aged , Indonesia , Torsades de Pointes/chemically induced
4.
Int J Pharm ; 658: 124186, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38701908

ABSTRACT

Because of the difficult challenges of nanopharmaceutics, the development of a variety of nanovectors is still highly desired. Photodynamic therapy, which uses a photosensitizer to locally produce reactive oxygen species to kill the undesired cells, is a typical example for which encapsulation has been shown to be beneficial. The present work describes the use of coumarin-functionalized polymeric nanovectors based on the self-assembly of amphiphilic poly(2-oxazoline)s. Encapsulation of pheophorbide a, a known PDT photosensitizer, is shown to lead to an increased efficiency compared to the un-encapsulated version. Interestingly, the presence of coumarin both enhances the desired photocytotoxicity and enables the crosslinking of the vectors. Various nanovectors are examined, differing by their size, shape and hydrophilicity. Their behaviour in PDT protocols on HCT-116 cells monolayers is described, the influence of their crosslinking commented. Furthermore, the formation of a protein corona is assessed.


Subject(s)
Coumarins , Oxazoles , Photochemotherapy , Photosensitizing Agents , Photochemotherapy/methods , Humans , Coumarins/chemistry , Oxazoles/chemistry , Photosensitizing Agents/chemistry , Photosensitizing Agents/pharmacology , HCT116 Cells , Cell Survival/drug effects , Chlorophyll/analogs & derivatives , Chlorophyll/chemistry , Chlorophyll/pharmacology , Nanoparticles/chemistry , Drug Carriers/chemistry , Polymers/chemistry
5.
JAMA Netw Open ; 7(4): e244435, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38568692

ABSTRACT

Importance: Little is known regarding the outcomes associated with tucatinib combined with trastuzumab and capecitabine (TTC) after trastuzumab-deruxtecan exposure among patients with ERBB2 (previously HER2)-positive metastatic breast cancer (MBC). Objective: To investigate outcomes following TTC treatment in patients with ERBB2-positive MBC who had previously received trastuzumab-deruxtecan. Design, Setting, and Participants: This cohort study included all patients with MBC who were treated in 12 French comprehensive cancer centers between August 1, 2020, and December 31, 2022. Exposure: Tucatinib combined with trastuzumab and capecitabine administered at the recommended dose. Main Outcomes and Measures: Clinical end points included progression-free survival (PFS), time to next treatment (TTNT), overall survival (OS), and overall response rate (ORR). Results: A total of 101 patients with MBC were included (median age, 56 [range, 31-85] years). The median number of prior treatment lines for metastatic disease at TTC treatment initiation was 4 (range, 2-15), including 82 patients (81.2%) with previous trastuzumab and/or pertuzumab and 94 (93.1%) with previous ado-trastuzumab-emtansine) exposure. The median duration of trastuzumab-deruxtecan treatment was 8.9 (range, 1.4-25.8) months, and 82 patients (81.2%) had disease progression during trastuzumab-deruxtecan treatment, whereas 18 (17.8%) had stopped trastuzumab-deruxtecan for toxic effects and 1 (1.0%) for other reasons. Tucatinib combined with trastuzumab and capecitabine was provided as a third- or fourth-line treatment in 37 patients (36.6%) and was the immediate treatment after trastuzumab-deruxtecan in 86 (85.1%). With a median follow-up of 11.6 (95% CI, 10.5-13.4) months, 76 of 101 patients (75.2%) stopped TTC treatment due to disease progression. The median PFS was 4.7 (95% CI, 3.9-5.6) months; median TTNT, 5.2 (95% CI, 4.5-7.0) months; and median OS, 13.4 (95% CI, 11.1 to not reached [NR]) months. Patients who received TTC immediately after trastuzumab-deruxtecan had a median PFS of 5.0 (95% CI, 4.2-6.0) months; median TTNT of 5.5 (95% CI, 4.8-7.2) months, and median OS of 13.4 (95% CI, 11.9-NR) months. Those who received TTC due to trastuzumab-deruxtecan toxicity-related discontinuation had a median PFS of 7.3 (95% CI, 3.0-NR) months. Best ORR was 29 of 89 patients (32.6%). Sixteen patients with active brain metastasis had a median PFS of 4.7 (95% CI, 3.0-7.3) months, median TTNT of 5.6 (95% CI, 4.4 to NR), and median OS of 12.4 (95% CI, 8.3-NR) months. Conclusions and Relevance: In this study, TTC therapy was associated with clinically meaningful outcomes in patients with ERBB2-positive MBC after previous trastuzumab-deruxtecan treatment, including those with brain metastases. Prospective data on optimal drug sequencing in this rapidly changing therapeutic landscape are needed.


Subject(s)
Brain Neoplasms , Breast Neoplasms , Oxazoles , Pyridines , Quinazolines , Humans , Middle Aged , Female , Breast Neoplasms/drug therapy , Capecitabine/therapeutic use , Cohort Studies , Prospective Studies , Trastuzumab/therapeutic use , Disease Progression , Receptor, ErbB-2
6.
Pestic Biochem Physiol ; 200: 105826, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38582590

ABSTRACT

Acetyl-CoA carboxylase (ACCase)-inhibiting herbicides are among the most commonly used herbicides to control grassy weeds, especially Leptochloa chinensis, in rice fields across China. Herein, we collected a suspected resistant (R) population of L. chinensis (HFLJ16) from Lujiang county in Anhui Province. Whole plant dose response tests showed that, compared with the susceptible (S) population, the R population showed high resistance to cyhalofop-butyl (22-fold) and displayed cross-resistance to metamifop (9.7-fold), fenoxaprop-P-ethyl (18.7-fold), quizalofop-P-ethyl (7.6-fold), clodinafop-propargyl (12-fold) and clethodim (8.4-fold). We detected an amino acid substitution (Cys-2088-Arg) in the ACCase of resistant L. chinensis. However, ACCase gene expression levels were not significantly different (P > 0.05) between R plants and S plants, without or with cyhalofop-butyl treatment. Furthermore, pretreatment with piperonyl butoxide (PBO, a cytochrome P450 monooxygenase (CYP450) inhibitor) or 4-chloro-7-nitrobenzoxadiazole (NBD-Cl, a glutathione-S-transferase (GST) inhibitor), inhibited the resistance of the R population to cyhalofop-butyl significantly (by approximately 60% and 26%, respectively). Liquid chromatography tandem mass spectrometry analysis showed that R plants metabolized cyhalofop-butyl and cyhalofop acid (its metabolite) significantly faster than S plants. Three CYP450 genes, one GST gene, and two ABC transporter genes were induced by cyhalofop-butyl and were overexpressed in the R population. Overall, GST-associated detoxification, CYP450 enhancement, and target-site gene mutation are responsible for the resistance of L. chinensis to cyhalofop-butyl.


Subject(s)
4-Chloro-7-nitrobenzofurazan , Acetyl-CoA Carboxylase , Butanes , Herbicides , Nitriles , Oxazoles , Propionates , Acetyl-CoA Carboxylase/metabolism , Plant Proteins/genetics , Poaceae/genetics , Poaceae/metabolism , Herbicides/pharmacology , Cytochrome P-450 Enzyme System/genetics , Mutation , Herbicide Resistance/genetics
8.
Nat Microbiol ; 9(5): 1325-1339, 2024 May.
Article in English | MEDLINE | ID: mdl-38589468

ABSTRACT

Drug-resistant fungal infections pose a significant threat to human health. Dual-targeting compounds, which have multiple targets on a single pathogen, offer an effective approach to combat drug-resistant pathogens, although ensuring potent activity and high selectivity remains a challenge. Here we propose a dual-targeting strategy for designing antifungal compounds. We incorporate DNA-binding naphthalene groups as the hydrophobic moieties into the host defence peptide-mimicking poly(2-oxazoline)s. This resulted in a compound, (Gly0.8Nap0.2)20, which targets both the fungal membrane and DNA. This compound kills clinical strains of multidrug-resistant fungi including Candida spp., Cryptococcus neoformans, Cryptococcus gattii and Aspergillus fumigatus. (Gly0.8Nap0.2)20 shows superior performance compared with amphotericin B by showing not only potent antifungal activities but also high antifungal selectivity. The compound also does not induce antimicrobial resistance. Moreover, (Gly0.8Nap0.2)20 exhibits promising in vivo therapeutic activities against drug-resistant Candida albicans in mouse models of skin abrasion, corneal infection and systemic infection. This study shows that dual-targeting antifungal compounds may be effective in combating drug-resistant fungal pathogens and mitigating fungal resistance.


Subject(s)
Antifungal Agents , Microbial Sensitivity Tests , Antifungal Agents/pharmacology , Antifungal Agents/chemistry , Animals , Mice , Humans , Drug Resistance, Multiple, Fungal , Disease Models, Animal , Cryptococcus neoformans/drug effects , Aspergillus fumigatus/drug effects , Candida albicans/drug effects , Naphthalenes/pharmacology , Naphthalenes/chemistry , Oxazoles/pharmacology , Oxazoles/chemistry , Candida/drug effects , Mycoses/drug therapy , Mycoses/microbiology
9.
Environ Sci Pollut Res Int ; 31(19): 28754-28763, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38558345

ABSTRACT

Fenoxaprop-p-ethyl (FE) is one of the typical aryloxyphenoxypropionate herbicides. FE has been widely applied in agriculture in recent years. Human health and aquatic ecosystems are threatened by the cyanobacteria blooms caused by Microcystis aeruginosa, which is one of the most common cyanobacteria responsible for freshwater blooming. Few studies have been reported on the physiological effects of FE on M. aeruginosa. This study analyzed the growth curves, the contents of chlorophyll a and protein, the oxidative stress, and the microcystin-LR (MC-LR) levels of M. aeruginosa exposed to various FE concentrations (i.e., 0, 0.5, 1, 2, and 5 mg/L). FE was observed to stimulate the cell density, chlorophyll a content, and protein content of M. aeruginosa at 0.5- and 1-mg/L FE concentrations but inhibit them at 2 and 5 mg/L FE concentrations. The superoxide dismutase and catalase activities were enhanced and the malondialdehyde concentration was increased by FE. The intracellular (intra-) and extracellular (extra-) MC-LR contents were also affected by FE. The expression levels of photosynthesis-related genes psbD1, psaB, and rbcL varied in response to FE exposure. Moreover, the expressions of microcystin synthase-related genes mcyA and mcyD and microcystin transportation-related gene mcyH were significantly inhibited by the treatment with 2 and 5 mg/L FE concentrations. These results might be helpful in evaluating the ecotoxicity of FE and guiding the rational application of herbicides in modern agriculture.


Subject(s)
Herbicides , Marine Toxins , Microcystis , Oxazoles , Microcystis/drug effects , Herbicides/toxicity , Antioxidants/metabolism , Oxidative Stress/drug effects , Propionates , Gene Expression/drug effects , Microcystins
10.
Brain Res Bull ; 211: 110943, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38614408

ABSTRACT

BACKGROUND: Existing evidence suggests that the composition of the gut microbiota is associated with neuropathic pain (NP), but the mechanistic link is elusive. Peroxisome proliferator-activated receptor α (PPARα) has been shown to be a pharmacological target for the treatment of metabolic disorders, and its expression is also involved in inflammatory regulation. The aim of this study was to investigate the important modulatory effects of PPARα on gut microbiota and spinal cord metabolites in mice subjected to chronic constriction injury. METHODS: We analyzed fecal microbiota and spinal cord metabolic alterations in mice from the sham, CCI, GW7647 (PPARα agonist) and GW6471 (PPARα antagonist) groups by 16 S rRNA amplicon sequencing and untargeted metabolomics analysis. On this basis, the intestinal microbiota and metabolites that were significantly altered between treatment groups were analyzed in a combined multiomics analysis. We also investigated the effect of PPARα on the polarization fractionation of spinal microglia. RESULTS: PPARα agonist significantly reduce paw withdrawal threshold and paw withdrawal thermal latency, while PPARα antagonist significantly increase paw withdrawal threshold and paw withdrawal thermal latency. 16 S rRNA gene sequencing showed that intraperitoneal injection of GW7647 or GW6471 significantly altered the abundance, homogeneity and composition of the gut microbiome. Analysis of the spinal cord metabolome showed that the levels of spinal cord metabolites were shifted after exposure to GW7647 or GW6471. Alterations in the composition of gut microbiota were significantly associated with the abundance of various spinal cord metabolites. The abundance of Licheniformes showed a significant positive correlation with nicotinamide, benzimidazole, eicosanoids, and pyridine abundance. Immunofluorescence results showed that intraperitoneal injection of GW7647 or GW6471 altered microglial activation and polarization levels. CONCLUSION: Our study shows that PPARα can promote M2-type microglia polarization, as well as alter gut microbiota and metabolites in CCI mice. This study enhances our understanding of the mechanism of PPARα in the treatment of neuropathic pain.


Subject(s)
Gastrointestinal Microbiome , Metabolomics , Neuralgia , PPAR alpha , RNA, Ribosomal, 16S , Spinal Cord , Animals , Male , Mice , Feces/microbiology , Gastrointestinal Microbiome/drug effects , Gastrointestinal Microbiome/physiology , Mice, Inbred C57BL , Microglia/metabolism , Microglia/drug effects , Neuralgia/metabolism , Neuralgia/drug therapy , Neuralgia/microbiology , Oxazoles , PPAR alpha/metabolism , RNA, Ribosomal, 16S/genetics , Spinal Cord/metabolism , Spinal Cord/drug effects , Tyrosine/analogs & derivatives
11.
Drug Alcohol Depend ; 259: 111276, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38676968

ABSTRACT

BACKGROUND: As nicotine dependence represents a longstanding major public health issue, new nicotine cessation pharmacotherapies are needed. Administration of N-oleoyl glycine (OlGly), an endogenous lipid signaling molecule, prevents nicotine-induced conditioned place preference (CPP) through a peroxisome proliferator-activated receptor-alpha (PPARα) dependent mechanism, and also ameliorated withdrawal signs in nicotine-dependent mice. Pharmacological evidence suggests that the methylated analog of OlGly, N-oleoyl alanine (OlAla), has an increased duration of action and may offer translational benefit. Accordingly, OlAla was assessed in nicotine CPP and dependence assays as well as its pharmacokinetics compared to OlGly. METHODS: ICR female and male mice were tested in nicotine-induced CPP with and without the PPARα antagonist GW6471. OlAla was also assessed in nicotine-dependent mice following removal of nicotine minipumps: somatic withdrawal signs, thermal hyper-nociception and altered affective behavior (i.e., light/dark box). Finally, plasma and brain were collected after administration of OlGly or OlAla and analyzed by high-performance liquid chromatography tandem mass spectrometry. RESULTS: OlAla prevented nicotine-induced CPP, but this effect was not blocked by GW6471. OlAla attenuated somatic and affective nicotine withdrawal signs, but not thermal hyper-nociception in nicotine-dependent mice undergoing withdrawal. OlAla and OlGly showed similar time-courses in plasma and brain. CONCLUSIONS: The observation that both molecules showed similar pharmacokinetics argues against the notion that OlAla offers increased metabolic stability. Moreover, while these structurally similar lipids show efficacy in mouse models of reward and dependence, they reduce nicotine reward through distinct mechanisms.


Subject(s)
Mice, Inbred ICR , Nicotine , Reward , Substance Withdrawal Syndrome , Tobacco Use Disorder , Animals , Substance Withdrawal Syndrome/metabolism , Substance Withdrawal Syndrome/drug therapy , Mice , Male , Nicotine/pharmacology , Female , Tobacco Use Disorder/metabolism , PPAR alpha/metabolism , Alanine/pharmacology , Alanine/analogs & derivatives , Oleic Acids/pharmacology , Glycine/pharmacology , Glycine/analogs & derivatives , Aminopyridines/pharmacology , Brain/metabolism , Brain/drug effects , Oxazoles , Tyrosine/analogs & derivatives
12.
Molecules ; 29(8)2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38675561

ABSTRACT

The search for novel effective TAAR1 ligands continues to draw great attention due to the wide range of pharmacological applications related to TAAR1 targeting. Herein, molecular docking studies of known TAAR1 ligands, characterized by an oxazoline core, have been performed in order to identify novel promising chemo-types for the discovery of more active TAAR1 agonists. In particular, the oxazoline-based compound S18616 has been taken as a reference compound for the computational study, leading to the development of quite flat and conformationally locked ligands. The choice of a "Y-shape" conformation was suggested for the design of TAAR1 ligands, interacting with the protein cavity delimited by ASP103 and aromatic residues such as PHE186, PHE195, PHE268, and PHE267. The obtained results allowed us to preliminary in silico screen an in-house series of pyrimidinone-benzimidazoles (1a-10a) as a novel scaffold to target TAAR1. Combined ligand-based (LBCM) and structure based (SBCM) computational methods suggested the biological evaluation of compounds 1a-10a, leading to the identification of derivatives 1a-3a (hTAAR1 EC50 = 526.3-657.4 nM) as promising novel TAAR1 agonists.


Subject(s)
Molecular Docking Simulation , Receptors, G-Protein-Coupled , Receptors, G-Protein-Coupled/agonists , Receptors, G-Protein-Coupled/metabolism , Receptors, G-Protein-Coupled/chemistry , Humans , Ligands , Structure-Activity Relationship , Models, Molecular , Protein Binding , Binding Sites , Oxazoles/chemistry , Oxazoles/pharmacology , Benzimidazoles/chemistry , Benzimidazoles/pharmacology , Molecular Structure , Drug Discovery
13.
Breast Dis ; 43(1): 61-64, 2024.
Article in English | MEDLINE | ID: mdl-38578876

ABSTRACT

BACKGROUND: Tucatinib is a tyrosine kinase inhibitor currently used in salvage therapy for human epidermal growth factor receptor 2 (HER2)-positive breast and colorectal cancer. The use of tucatinib alone or in combination with ado-trastuzumab emtansine (T-DM1) in the treatment of advanced HER2-positive cancers is rapidly expanding. OBJECTIVE/METHODS: We report the case of a 66-year-old female who presented to the dermatology clinic with a one-year history of widespread telangiectasias that began after initiation of combination chemotherapy with tucatinib and T-DM1 for metastatic HER2-positive invasive ductal carcinoma. RESULTS: The patient's lesions regressed upon cessation of combination therapy and reappeared in the setting of tucatinib re-initiation, with gradual improvement over the following four months following electrocautery to the affected regions. CONCLUSIONS: We postulate that telangiectasias may be a previously unreported dermatologic side effect of combination treatment with tucatinib and T-DM1. Electrocautery is a safe and effective procedure to reduce the appearance of telangiectasias and improve patient satisfaction during chemotherapy.


Subject(s)
Breast Neoplasms , Oxazoles , Pyridines , Female , Humans , Aged , Ado-Trastuzumab Emtansine/therapeutic use , Breast Neoplasms/pathology , Trastuzumab/adverse effects , Quinazolines/therapeutic use , Receptor, ErbB-2/genetics , Receptor, ErbB-2/metabolism , Antineoplastic Combined Chemotherapy Protocols/adverse effects
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124337, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-38676988

ABSTRACT

Polarity is a vital element in endoplasmic reticulum (ER) microenvironment, and its variation is closely related to many physiological and pathological activities of ER, so it is necessary to trace fluctuations of polarity in ER. However, most of fluorescent probes for detecting polarity dependent on the changes of single emission, which could be affected by many factors and cause false signals. Ratiometric fluorescent probe with "built-in calibration" can effectively avoid detection errors. Here, we have designed a ratiometric fluorescent probe HM for monitoring the ER polarity based on the intramolecular reaction of spiro-oxazolidine. It forms ring open/closed isomers driven by polarity to afford ratiometric sensing. Probe HM have manifested its ratiometric responses to polarity in spectroscopic results, which could offer much more precise information for the changes of polarity in living cells with the internal built-in correction. It also showed large emission shift ( 133 nm), high selectivity and photo-stability. In biological imaging, HM could selectively accumulate in ER with high photo-stability. Importantly, HM has ability for in situ tracing the changes of ER polarity with ratiometric behavior during the ER stress process with the stimulation of tunicamycin, dithiothreitol and hypoxia, suggesting that HM is an effective molecule tool for monitoring the variations of ER polarity.


Subject(s)
Endoplasmic Reticulum Stress , Fluorescent Dyes , Oxazoles , Spiro Compounds , Fluorescent Dyes/chemistry , Fluorescent Dyes/chemical synthesis , Humans , Spiro Compounds/chemistry , Oxazoles/chemistry , Endoplasmic Reticulum Stress/drug effects , Spectrometry, Fluorescence , HeLa Cells , Endoplasmic Reticulum/metabolism
15.
Int J Mol Sci ; 25(8)2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38673739

ABSTRACT

Pseudoproline derivatives such as Thr(ΨPro)-OH are commonly used in peptide synthesis to reduce the likelihood of peptide aggregation and to prevent aspartimide (Asi) formation during the synthesis process. In this study, we investigate notable by-products such as aspartimide formation and an imine derivative of the Thr(ΨPro) moiety observed in flow peptide chemistry synthesis. To gain insight into the formation of these unexpected by-products, we design a series of experiments. Furthermore, we demonstrate the oxazolidine character of the pseudoproline moiety and provide plausible mechanisms for the two-way ring opening of oxazolidine leading to these by-products. In addition, we present evidence that Asi formation appears to be catalyzed by the presence of the pseudoproline moiety. These observed side reactions are attributed to elevated temperature and pressure; therefore, caution is advised when using ΨPro derivatives under such harsh conditions. In addition, we propose a solution whereby thermodynamically controlled Asi formation can be kinetically prevented.


Subject(s)
Oxazoles , Peptides , Oxazoles/chemistry , Peptides/chemistry , Thermodynamics
16.
Bioorg Med Chem ; 102: 117663, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38457910

ABSTRACT

We report the development of a new oxazole-based cleavable linker to release peptides from attached cargo. Oxazoles are stable to most reaction conditions, yet they can be rapidly cleaved in the presence of single-electron oxidants like cerium ammonium nitrate (CAN). An oxazole linker could be synthesized and attached to peptides through standard solid-phase peptide coupling reactions. Cleavage of these peptide-oxazole conjugates is demonstrated on a broad scope of peptides containing various natural and unnatural amino acids. These results represent the first example of a peptide-based linker that is cleaved through single-electron oxidation. The oxazole is also demonstrated to be a suitable linker for both the release of a peptide from a conjugated small molecule and the orthogonal release of cargo from a peptide containing multiple cleavable linkers. Oxazole linkers could serve as a promising tool for peptide screening platforms such as peptide-encoded libraries.


Subject(s)
Oxazoles , Peptides , Oxazoles/chemistry , Peptides/chemistry , Amino Acids/chemistry , Peptide Library , Oxidation-Reduction
17.
Int J Pharm ; 655: 124031, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38521375

ABSTRACT

Tuberculosis (TB) is a serious health issue that contributes to millions of deaths throughout the world and increases the threat of serious pulmonary infections in patients with respiratory illness. Delamanid is a novel drug approved in 2014 to deal with multi-drug resistant TB (MDR-TB). Despite its high efficiency in TB treatment, delamanid poses delivery challenges due to poor water solubility leading to inadequate absorption upon oral administration. This study involves the development of novel formulation-based pressurized metered dose inhalers (pMDIs) containing self-microemulsifying mixtures of delamanid for efficient delivery to the lungs. To identify the appropriate self-microemulsifying formulations, ternary diagrams were plotted using different combinations of surfactant to co-surfactant ratios (1:1, 2:1, and 3:1). The combinations used Cremophor RH40, Poly Ethylene Glycol 400 (PEG 400), and peppermint oil, and those that showed the maximum microemulsion region and rapid and stable emulsification were selected for further characterization. The diluted self-microemulsifying mixtures underwent evaluation of dose uniformity, droplet size, zeta potential, and transmission electron microscopy. The selected formulations exhibited uniform delivery of the dose throughout the canister life, along with droplet sizes and zeta potentials that ranged from 24.74 to 88.99 nm and - 19.27 to - 10.00 mV, respectively. The aerosol performance of each self-microemulsifying drug delivery system (SMEDDS)-pMDI was assessed using the Next Generation Impactor, which indicated their capability to deliver the drug to the deeper areas of the lungs. In vitro cytotoxicity testing on A549 and NCI-H358 cells revealed no significant signs of toxicity up to a concentration of 1.56 µg/mL. The antimycobacterial activity of the formulations was evaluated against Mycobacterium bovis using flow cytometry analysis, which showed complete inhibition by day 5 with a minimum bactericidal concentration of 0.313 µg/mL. Moreover, the cellular uptake studies showed efficient delivery of the formulations inside macrophage cells, which indicated the potential for intracellular antimycobacterial activity. These findings demonstrated the potential of the Delamanid-SMEDDS-pMDI for efficient pulmonary delivery of delamanid to improve its effectiveness in the treatment of multi-drug resistant pulmonary TB.


Subject(s)
Nitroimidazoles , Oxazoles , Tuberculosis, Multidrug-Resistant , Tuberculosis, Pulmonary , Humans , Lung , Metered Dose Inhalers , Tuberculosis, Multidrug-Resistant/drug therapy , Surface-Active Agents , Solubility , Drug Delivery Systems , Emulsions , Biological Availability
18.
Int J Mol Sci ; 25(5)2024 Feb 20.
Article in English | MEDLINE | ID: mdl-38473712

ABSTRACT

Canine-mammary-gland tumors (CMTs) are prevalent in female dogs, with approximately 50% of them being malignant and often presenting as inoperable owing to their size or metastasis. Owing to poor outcomes, effective alternatives to conventional chemotherapy for humans are necessary. Two estrogen receptors, estrogen receptor alpha (ERα) and estrogen receptor beta (ERß), which act in opposition to each other, are involved, and CMT growth involves ERα through the phosphoinositide 3-kinases (PI3K)/AKT pathway. In this study, we aimed to identify the synergistic anti-cancer effects of ERB-041, an ERß agonist, and genistein, an isoflavonoid from soybeans known to have ERß-specific pseudo-estrogenic actions, on CMT-U27 and CF41.Mg CMT cell lines. ERB-041 and genistein synergistically inhibited cell proliferation and increased the number of annexin V-positive cells in both cell lines. Furthermore, we observed a synergistic increase in the Bax/Bcl-2 ratio and cleaved caspase-3 expression. Additionally, cell-cycle arrest occurred through the synergistic regulation of cyclin D1 and cyclin-dependent kinase 4 (CDK4). We also found a synergistic decrease in the expression of ERα, and the expression of proteins involved in the PI3K/AKT pathway, including p-PI3K, phosphatase and tensin homolog (PTEN), AKT, and mechanistic target of rapamycin (mTOR). In conclusion, ERB-041 and genistein exhibited a synergistic anticancer effect on CMTs, suggesting that cotreatment with ERB-041 and genistein is a promising treatment for CMTs.


Subject(s)
Mammary Glands, Human , Oxazoles , Receptors, Estrogen , Dogs , Animals , Female , Humans , Receptors, Estrogen/metabolism , Genistein/pharmacology , Estrogen Receptor beta/genetics , Estrogen Receptor alpha/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Down-Regulation , Mammary Glands, Human/metabolism , Estrogens/metabolism
19.
Angew Chem Int Ed Engl ; 63(21): e202402465, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38482567

ABSTRACT

A targeted metabologenomic method was developed to selectively discover terminal oxazole-bearing natural products from bacteria. For this, genes encoding oxazole cyclase, a key enzyme in terminal oxazole biosynthesis, were chosen as the genomic signature to screen bacterial strains that may produce oxazole-bearing compounds. Sixteen strains were identified from the screening of a bacterial DNA library (1,000 strains) using oxazole cyclase gene-targeting polymerase chain reaction (PCR) primers. The PCR amplicon sequences were subjected to phylogenetic analysis and classified into nine clades. 1H-13C coupled-HSQC NMR spectra obtained from the culture extracts of the hit strains enabled the unequivocal detection of the target compounds, including five new oxazole compounds, based on the unique 1JCH values and chemical shifts of oxazole: lenzioxazole (1) possessing an unprecedented cyclopentane, permafroxazole (2) bearing a tetraene conjugated with carboxylic acid, tenebriazine (3) incorporating two modified amino acids, and methyl-oxazolomycins A and B (4 and 5). Tenebriazine displayed inhibitory activity against pathogenic fungi, whereas methyl-oxazolomycins A and B (4 and 5) selectively showed anti-proliferative activity against estrogen receptor-positive breast cancer cells. This metabologenomic method enables the logical and efficient discovery of new microbial natural products with a target structural motif without the need for isotopic labeling.


Subject(s)
Biological Products , Oxazoles , Oxazoles/chemistry , Oxazoles/pharmacology , Oxazoles/metabolism , Biological Products/chemistry , Biological Products/pharmacology , Biological Products/metabolism , Humans , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Cell Line, Tumor , Metabolomics , Molecular Structure , Cell Proliferation/drug effects , Drug Discovery , Bacteria/drug effects
20.
Skinmed ; 22(1): 61-66, 2024.
Article in English | MEDLINE | ID: mdl-38494618

ABSTRACT

XdemvyTM (lotilaner ophthalmic solution) 0.25% topical solution was recently approved for the treatment of Demodex blepharitis in adults aged ≥18 years. As an antiparasitic agent, lotilaner selectively inhibits gamma-aminobutyric acid chloride channels specific to the parasite and induces spastic paralysis, leading to death of Demodex blepharitis mites. In two randomized, double-masked, vehicle-controlled, multi-center, phase-3 clinical trials (Saturn-1 and Satuirn-2), lotilaner 0.25% topical solution was investigated for the treatment of Demodex blepharitis. Patients were assigned to receive either lotilaner 0.25% topical solution or vehicle (solution that did not contain lotilaner as an active ingredient) twice daily for 6 weeks. On day 43, lotilaner group demonstrated primary efficacy in achieving collarette cure ([collarette grade 0], Saturn-1: study group 44% [92/209], vehicle 7.4% [15/204]; Saturn-2: study group 56% [108/193], vehicle 12.5% [25/200]). Secondary efficacy was achieved by eradication of mite ([0 mite/lash], Saturn-1: study group 67.9% [142/209], vehicle 17.6% [36/304]; Saturn-2: study group 51.8% [99/193], vehicle 14.6% [29/200]), composite cure ([grade 0 collarette as well as grade 0 erythema], Saturn-1: study group 13.9% [29/209], vehicle 1.0% [2/204]; Saturn-2: study group 19.2% [37/193], vehicle 4% [8/200]), and erythema cure ([grade 0 erythema], study group 19.1% [40/209], vehicle 6.9% [14/204]; Saturn-2: study group 31.1% [60/193], vehicle 9.0% [18/199]). The adverse events were mild, with the most common being pain at instillation site. The recommended regimen for lotilaner 0.25% solution is one drop in each eye twice daily for 6 weeks.


Subject(s)
Blepharitis , Mite Infestations , Oxazoles , Thiophenes , Adolescent , Adult , Humans , Blepharitis/drug therapy , Blepharitis/parasitology , Erythema , Mite Infestations/drug therapy , Mite Infestations/parasitology , Ophthalmic Solutions/therapeutic use , Randomized Controlled Trials as Topic , Multicenter Studies as Topic , Clinical Trials, Phase III as Topic
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