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Frontiers in Pharmacology 2024plants were traditionally used to treat diseases associated with endothelial dysfunction. The present study investigated the effects of an ethanolic extract of Willd....
plants were traditionally used to treat diseases associated with endothelial dysfunction. The present study investigated the effects of an ethanolic extract of Willd. (commonly named water lily, WL) and its main compound (quercetin 3-methyl ether 3'-O--xylopyranoside) on vascular function in rats. The vasorelaxant effects of the WL extract and its main compound and their underlying mechanisms of action were evaluated on isolated mesenteric arteries from Wistar rats. Blood pressure and heart rate were measured in anesthetized rats after infusion (i.v) of vehicle, WL extract, and compound (at 0.01, 0.025, 0.05, 0.1, 0.5, and 1 mg/kg). Nifedipine was used as a positive control. Both WL extract and compound induced vasorelaxant effects (with EC of 0.08 ± 0.01 mg/mL and 42.8 ± 6.3 µM, respectively) that were reduced by endothelium removal. A significant decrease in these relaxations was observed with L-NAME but not with apamin-charybdotoxin or indomethacin. In the endothelium-denuded condition, WL extract-induced relaxation was enhanced by 4-aminopyridine and glibenclamide, while iberiotoxin and ODQ (1H-[1,2,4]oxadiazolo[4,3-a]quinoxaline-1-one) had no effect. In contrast, compound -induced relaxation was not changed by any of these inhibitors. Both WL extract and compound enhanced sodium nitroprusside-induced relaxation and inhibited receptor-operated Ca channels. Only the WL extract was able to reduce PE-induced contraction ( < 0.001). As compared to the vehicle, the infusion of WL extract and compound lowered systolic and diastolic blood pressure. Interestingly, the hypotensive effect of the compound was similar to that of nifedipine. The rebound tachycardia found at the highest dose of nifedipine was not observed with the WL extract or compound ( < 0.05). Our study demonstrated a vasorelaxant effect of the WL extract and its main compound quercetin 3-methyl ether 3'-O--xylopyranoside, relying on the potentiation of the NO-cGMP pathway and calcium inhibitory effects. These vasorelaxant effects were associated with a potent hypotensive effect, providing pharmacological evidence for the traditional use of this plant.
PubMed: 38576494
DOI: 10.3389/fphar.2024.1379752 -
Communications Biology Apr 2024The CLIP1-LTK fusion was recently discovered as a novel oncogenic driver in non-small cell lung cancer (NSCLC). Lorlatinib, a third-generation ALK inhibitor, exhibited a...
The CLIP1-LTK fusion was recently discovered as a novel oncogenic driver in non-small cell lung cancer (NSCLC). Lorlatinib, a third-generation ALK inhibitor, exhibited a dramatic clinical response in a NSCLC patient harboring CLIP1-LTK fusion. However, it is expected that acquired resistance will inevitably develop, particularly by LTK mutations, as observed in NSCLC induced by oncogenic tyrosine kinases treated with corresponding tyrosine kinase inhibitors (TKIs). In this study, we evaluate eight LTK mutations corresponding to ALK mutations that lead to on-target resistance to lorlatinib. All LTK mutations show resistance to lorlatinib with the L650F mutation being the highest. In vitro and in vivo analyses demonstrate that gilteritinib can overcome the L650F-mediated resistance to lorlatinib. In silico analysis suggests that introduction of the L650F mutation may attenuate lorlatinib-LTK binding. Our study provides preclinical evaluations of potential on-target resistance mutations to lorlatinib, and a novel strategy to overcome the resistance.
Topics: Humans; Carcinoma, Non-Small-Cell Lung; Lung Neoplasms; Anaplastic Lymphoma Kinase; Drug Resistance, Neoplasm; Lactams, Macrocyclic; Mutation; Cytoskeletal Proteins; Receptor Protein-Tyrosine Kinases; Aminopyridines; Lactams; Pyrazoles
PubMed: 38575808
DOI: 10.1038/s42003-024-06116-6 -
Journal of Experimental & Clinical... Apr 2024Brain metastasis (BM) is common among cases of advanced non-small cell lung cancer (NSCLC) and is the leading cause of death for these patients. Mesothelin (MSLN), a...
BACKGROUND
Brain metastasis (BM) is common among cases of advanced non-small cell lung cancer (NSCLC) and is the leading cause of death for these patients. Mesothelin (MSLN), a tumor-associated antigen expressed in many solid tumors, has been reported to be involved in the progression of multiple tumors. However, its potential involvement in BM of NSCLC and the underlying mechanism remain unknown.
METHODS
The expression of MSLN was validated in clinical tissue and serum samples using immunohistochemistry and enzyme-linked immunosorbent assay. The ability of NSCLC cells to penetrate the blood-brain barrier (BBB) was examined using an in vitro Transwell model and an ex vivo multi-organ microfluidic bionic chip. Immunofluorescence staining and western blotting were used to detect the disruption of tight junctions. In vivo BBB leakiness assay was performed to assess the barrier integrity. MET expression and activation was detected by western blotting. The therapeutic efficacy of drugs targeting MSLN (anetumab) and MET (crizotinib/capmatinib) on BM was evaluated in animal studies.
RESULTS
MSLN expression was significantly elevated in both serum and tumor tissue samples from NSCLC patients with BM and correlated with a poor clinical prognosis. MSLN significantly enhanced the brain metastatic abilities of NSCLC cells, especially BBB extravasation. Mechanistically, MSLN facilitated the expression and activation of MET through the c-Jun N-terminal kinase (JNK) signaling pathway, which allowed tumor cells to disrupt tight junctions and the integrity of the BBB and thereby penetrate the barrier. Drugs targeting MSLN (anetumab) and MET (crizotinib/capmatinib) effectively blocked the development of BM and prolonged the survival of mice.
CONCLUSIONS
Our results demonstrate that MSLN plays a critical role in BM of NSCLC by modulating the JNK/MET signaling network and thus, provides a potential novel therapeutic target for preventing BM in NSCLC patients.
Topics: Humans; Animals; Mice; Carcinoma, Non-Small-Cell Lung; Mesothelin; Lung Neoplasms; GPI-Linked Proteins; Crizotinib; Cell Line, Tumor; Brain Neoplasms; Benzamides; Imidazoles; Triazines
PubMed: 38570866
DOI: 10.1186/s13046-024-03015-w -
Leukemia Research May 2024Limited treatment options are available for patients with relapsed/refractory acute myeloid leukemia (R/R AML). We recently reported results from the phase 3 IDHENTIFY... (Randomized Controlled Trial)
Randomized Controlled Trial
Limited treatment options are available for patients with relapsed/refractory acute myeloid leukemia (R/R AML). We recently reported results from the phase 3 IDHENTIFY trial (NCT02577406) showing improved response rates and event-free survival with enasidenib monotherapy compared with conventional care regimens (CCR) in heavily pretreated, older patients with late-stage R/R AML bearing IDH2 mutations. Here we investigated the prognostic impact of mutational burden and different co-mutation patterns at study entry within the predominant IDH2 variant subclasses, IDH2-R140 and IDH2-R172. The prognostic relevance of these variants is well documented in newly diagnosed AML, but data are lacking in R/R AML. In this large R/R AML patient cohort, targeted next-generation sequencing at baseline (screening) revealed distinct co-mutation patterns and mutational burden between subgroups bearing different IDH2 variants: variant IDH2-R140 was associated with greater mutational burden and was enriched predominantly with poor-risk mutations, including FLT3, RUNX1, and NRAS, while variant IDH2-R172 was associated with lower mutational burden and was preferentially co-mutated with DNMT3A. In multivariable analyses, RAS and RTK pathway mutations were significantly associated with decreased overall survival, after adjusting for treatment arm, IDH2 variant, and mutational burden. Importantly, enasidenib-mediated survival benefit was more pronounced in patients with IDH2-R172 variants.
Topics: Adult; Aged; Aged, 80 and over; Female; Humans; Male; Middle Aged; Aminopyridines; Drug Resistance, Neoplasm; Isocitrate Dehydrogenase; Leukemia, Myeloid, Acute; Mutation; Neoplasm Recurrence, Local; Prognosis; Triazines
PubMed: 38564986
DOI: 10.1016/j.leukres.2024.107497 -
Lung Cancer (Amsterdam, Netherlands) May 2024Lorlatinib is a brain-penetrant, third-generation tyrosine kinase inhibitor (TKI) indicated for the treatment of anaplastic lymphoma kinase (ALK)-positive metastatic... (Review)
Review
Lorlatinib is a brain-penetrant, third-generation tyrosine kinase inhibitor (TKI) indicated for the treatment of anaplastic lymphoma kinase (ALK)-positive metastatic non-small cell lung cancer (NSCLC). In clinical trials, lorlatinib has shown durable efficacy and a manageable safety profile in treatment-naive patients and in those who have experienced progression while receiving first- and/or second-generation ALK TKIs. Lorlatinib has a distinct safety profile from other ALK TKIs, including hyperlipidemia and central nervous system effects. Clinical trial data showed that most adverse events (AEs) can be managed effectively or reversed with dose modifications (such as dose interruptions or reductions) or with concomitant medications without compromising clinical efficacy or quality of life for patients. A pragmatic approach to managing AEs related to lorlatinib is required. We present patient-focused recommendations for the evaluation and management of select AEs associated with lorlatinib developed by clinicians and nurses with extensive lorlatinib expertise in routine clinical practice. The recommendations follow the general framework of "prepare, monitor, manage, reassess" to streamline AE management and assist in practical, actionable, and personalized patient care.
Topics: Humans; Lactams; Aminopyridines; Carcinoma, Non-Small-Cell Lung; Pyrazoles; Lung Neoplasms; Protein Kinase Inhibitors; Lactams, Macrocyclic; Anaplastic Lymphoma Kinase; Drug-Related Side Effects and Adverse Reactions; Antineoplastic Agents; Disease Management
PubMed: 38554546
DOI: 10.1016/j.lungcan.2024.107535 -
Journal of Alzheimer's Disease : JAD 2024Deposits of amyloid-β (Aβ) appear early in Alzheimer's disease (AD).
BACKGROUND
Deposits of amyloid-β (Aβ) appear early in Alzheimer's disease (AD).
OBJECTIVE
The aim of the present study was to compare the presence of cortical and subcortical Aβ in early AD using positron emission tomography (PET).
METHODS
Eight cognitively unimpaired (CU) subjects, 8 with mild cognitive impairment (MCI) and 8 with mild AD were examined with PET and [11C]AZD2184. A data driven cut-point for Aβ positivity was defined by Gaussian mixture model of isocortex binding potential (BPND) values.
RESULTS
Sixteen subjects (3 CU, 5 MCI and 8 AD) were Aβ-positive. BPND was lower in subcortical and allocortical regions compared to isocortex. Fifteen of the 16 Aβ-positive subjects displayed Aβ binding in striatum, 14 in thalamus and 10 in allocortical regions.
CONCLUSIONS
Aβ deposits appear to be widespread in early AD. It cannot be excluded that deposits appear simultaneously throughout the whole brain which has implications for improved diagnostics and disease monitoring.
Topics: Humans; Alzheimer Disease; Carbon Radioisotopes; Amyloid beta-Peptides; Cognitive Dysfunction; Positron-Emission Tomography; Neocortex; Aminopyridines; Benzothiazoles
PubMed: 38552111
DOI: 10.3233/JAD-231013 -
Respiratory Investigation May 2024Many disease-causing variants in the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) gene remain uncharacterized and untreated. Restoring the function of the...
BACKGROUND
Many disease-causing variants in the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) gene remain uncharacterized and untreated. Restoring the function of the impaired CFTR protein is the goal of personalized medicine, particularly in patients carrying rare CFTR variants. In this study, functional defects related to the rare R334W variant were evaluated after treatment with CFTR modulators or Roflumilast, a phosphodiesterase-4 inhibitor (PDE4i).
METHODS
Rectal organoids from subjects with R334W/2184insA and R334W/2183AA > G genotypes were used to perform the Forskolin-induced swelling (FIS) assay. Organoids were left drug-untreated or treated with modulators VX-770 (I), VX-445 (E), and VX-661 (T) mixed, and their combination (ETI). Roflumilast (R) was used alone or as a combination of I + R.
RESULTS
Our data show a significant increase in FIS rate following treatment with I alone. The combined use of modulators, such as ETI, did not increase further swelling than I alone, nor in protein maturation. Treatment with R shows an increase in FIS response similar to those of I, and the combination R + I significantly increases the rescue of CFTR activity.
CONCLUSIONS
Equivalent I and ETI treatment efficacy was observed for both genotypes. Furthermore, significant organoid swelling was observed with combined I + R used that supports the recently published data describing a potentiating effect of only I in patients carrying the variant R334W and, at the same time, corroborating the role of strategies that include PDE4 inhibitors further to potentiate the effect of I for this variant.
Topics: Humans; Cystic Fibrosis Transmembrane Conductance Regulator; Cystic Fibrosis; Phosphodiesterase 4 Inhibitors; Colforsin; Organoids; Mutation; Aminopyridines; Benzamides; Cyclopropanes
PubMed: 38547757
DOI: 10.1016/j.resinv.2024.03.003 -
EBioMedicine Apr 2024Sarcomas represent an extensive group of malignant diseases affecting mesodermal tissues. Among sarcomas, the clinical management of chondrosarcomas remains a complex...
BACKGROUND
Sarcomas represent an extensive group of malignant diseases affecting mesodermal tissues. Among sarcomas, the clinical management of chondrosarcomas remains a complex challenge, as high-grade tumours do not respond to current therapies. Mutations in the isocitrate dehydrogenase (IDH) 1 and 2 genes are among the most common mutations detected in chondrosarcomas and may represent a therapeutic opportunity. The presence of mutated IDH (mIDH) enzymes results in the accumulation of the oncometabolite 2-HG leading to molecular alterations that contribute to drive tumour growth.
METHODS
We developed a personalized medicine strategy based on the targeted NGS/Sanger sequencing of sarcoma samples (n = 6) and the use of matched patient-derived cell lines as a drug-testing platform. The anti-tumour potential of IDH mutations found in two chondrosarcoma cases was analysed in vitro, in vivo and molecularly (transcriptomic and DNA methylation analyses).
FINDINGS
We treated several chondrosarcoma models with specific mIDH1/2 inhibitors. Among these treatments, only the mIDH2 inhibitor enasidenib was able to decrease 2-HG levels and efficiently reduce the viability of mIDH2 chondrosarcoma cells. Importantly, oral administration of enasidenib in xenografted mice resulted in a complete abrogation of tumour growth. Enasidenib induced a profound remodelling of the transcriptomic landscape not associated to changes in the 5 mC methylation levels and its anti-tumour effects were associated with the repression of proliferative pathways such as those controlled by E2F factors.
INTERPRETATION
Overall, this work provides preclinical evidence for the use of enasidenib to treat mIDH2 chondrosarcomas.
FUNDING
Supported by the Spanish Research Agency/FEDER (grants PID2022-142020OB-I00; PID2019-106666RB-I00), the ISC III/FEDER (PI20CIII/00020; DTS18CIII/00005; CB16/12/00390; CB06/07/1009; CB19/07/00057); the GEIS group (GEIS-62); and the PCTI (Asturias)/FEDER (IDI/2021/000027).
Topics: Humans; Animals; Mice; Precision Medicine; Chondrosarcoma; Sarcoma; Isocitrate Dehydrogenase; Mutation; Bone Neoplasms; Aminopyridines; Triazines
PubMed: 38547578
DOI: 10.1016/j.ebiom.2024.105090 -
Biomedicines Feb 2024Glutamate is a major excitatory neurotransmitter that mediates neuronal damage in acute and chronic brain disorders. The effect and mechanism of phillygenin, a natural...
Glutamate is a major excitatory neurotransmitter that mediates neuronal damage in acute and chronic brain disorders. The effect and mechanism of phillygenin, a natural compound with neuroprotective potential, on glutamate release in isolated nerve terminals (synaptosomes) prepared from the rat cerebral cortex were examined. In this study, 4-aminopyridine (4-AP), a potassium channel blocker, was utilized to induce the release of glutamate, which was subsequently quantified via a fluorometric assay. Our findings revealed that phillygenin reduced 4-AP-induced glutamate release, and this inhibitory effect was reversed by removing extracellular Ca or inhibiting vesicular transport with bafilomycin A1. However, exposure to the glutamate transporter inhibitor dl-threo-beta-benzyl-oxyaspartate (dl-TOBA) did not influence the inhibitory effect. Moreover, phillygenin did not change the synaptosomal membrane potential but lowered the 4-AP-triggered increase in intrasynaptosomal Ca concentration ([Ca]). Antagonizing Ca2.2 (N-type) calcium channels blocked the inhibition of glutamate release by phillygenin, whereas pretreatment with the mitochondrial Na/Ca exchanger inhibitor, CGP37157 or the ryanodine receptor inhibitor, dantrolene, both of which block intracellular Ca release, had no effect. The effect of phillygenin on glutamate release triggered by 4-AP was completely abolished when MAPK/ERK inhibitors were applied. Furthermore, phillygenin attenuated the phosphorylation of ERK1/2 and its major presynaptic target, synapsin I, a protein associated with synaptic vesicles. These data collectively suggest that phillygenin mediates the inhibition of evoked glutamate release from synaptosomes primarily by reducing the influx of Ca through Ca2.2 calcium channels, thereby subsequently suppressing the MAPK/ERK/synapsin I signaling cascade.
PubMed: 38540109
DOI: 10.3390/biomedicines12030495 -
Toxins Feb 2024Ciguatoxins (CTXs) are neurotoxins responsible for ciguatera poisoning (CP), which affects more than 50,000 people worldwide annually. The development of analytical...
Ciguatoxins (CTXs) are neurotoxins responsible for ciguatera poisoning (CP), which affects more than 50,000 people worldwide annually. The development of analytical methods to prevent CP is a pressing global issue, and the N2a assay is one of the most promising methods for detecting CTXs. CTXs are highly toxic, and an action level of 0.01 μg CTX1B equivalent (eq)/kg in fish has been proposed. It is desirable to further increase the detection sensitivity of CTXs in the N2a assay to detect such low concentrations reliably. The opening of voltage-gated sodium channels (Na channels) and blocking of voltage-gated potassium channels (K channels) are thought to be involved in the toxicity of CTXs. Therefore, in this study, we developed an assay that could detect CTXs with higher sensitivity than conventional N2a assays, using K channel inhibitors as sensitizing reagents for N2a cells. The addition of the K channel inhibitors 4-aminopyridine and tetraethylammonium chloride to N2a cells, in addition to the traditional sensitizing reagents ouabain and veratridine, increased the sensitivity of N2a cells to CTXs by up to approximately 4-fold. This is also the first study to demonstrate the influence of K channels on the toxicity of CTXs in a cell-based assay.
Topics: Humans; Animals; Ciguatoxins; Ciguatera Poisoning; Aminopyridines; Potassium Channels, Voltage-Gated; Neuroblastoma
PubMed: 38535783
DOI: 10.3390/toxins16030118