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219
result(s) for
"methoxsalen"
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Evaluation of Alkaloids Isolated from Ruta graveolens as Photosynthesis Inhibitors
by
Lotina-Hennsen, Blas
,
Bellete, Barbara Sayuri
,
King-Diaz, Beatriz
in
acridone alkaloids
,
Alkaloids - chemistry
,
Alkaloids - isolation & purification
2018
Eight alkaloids (1–8) were isolated from Ruta graveolens, and their herbicide activities were evaluated through in vitro, semivivo, and in vivo assays. The most relevant results were observed for Compounds 5 and 6–8 at 150 μM, which decreased dry biomass by 20% and 23%, respectively. These are significant results since they presented similar values with the positive control, commercial herbicide 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU). Based on the performed assays, Compound 5 (graveoline) is classified as an electron-transport inhibitor during the light phase of photosynthesis, as well as a plant-growth regulator. On the other hand, Compounds 6–8 inhibited electron and energy transfers, and are also plant-growth inhibitors. These phytotoxic behaviors based on acridone and quinolone alkaloids may serve as a valuable tool in the further development of a new class of herbicides since natural products represent an interesting alternative to replace commercial herbicides, potentially due their low toxicity.
Journal Article
Traumatic Brain Injury-Mediated Neuroinflammation and Neurological Deficits are Improved by 8-Methoxypsoralen Through Modulating PPARγ/NF-κB Pathway
by
Zhang, Haitao
,
Shi, Lei
,
Hui, Yuzuo
in
Animals
,
Anti-Inflammatory Agents - pharmacology
,
Apoptosis
2023
8-Methoxypsoralen (8-MOP) has anti-inflammatory, antioxidant and tissue-repairing abilities. Here, we probed the function and mechanism of 8-MOP in traumatic brain injury (TBI). The
in
-
vivo
TBI model was constructed in Sprague-Dawley (SD) rats using controlled cortical impact (CCI) surgery. In parallel, BV2 microglia and HT22 neurons were activated by lipopolysaccharide (LPS) to establish an
in-vitro
model. The modified neurological score (mNSS) and the Morris water maze experiment were employed to evaluate the rats’ neurological functions. The rats’ brain edema was assessed by the dry and wet method, and neuronal apoptosis in damaged brain tissues was monitored by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) and Nissl’s staining. Immunohistochemistry (IHC) was applied to verify Iba1-microglial activation in brain lesions of rats. The expression of inflammatory cytokines in BV2 microglia and HT22 neurons in the injured lesion of TBI rats was examined by the enzyme-linked immunosorbent assay (ELISA). The levels of iNOS, COX2, TLR4, PPARγ, STAT3, and NF-κB in brain lesions, BV2 microglia and HT22 neurons were compared by Western blot. As a result, 8-MOP administration reduced inflammation and LPS-induced neuronal damage in BV2 microglia. In vivo, 8-MOP treatment relieved neurological deficits in TBI rats, improved cognitive, learning and motor functions and mitigated brain edema and neuroinflammation induced by TBI. Furthermore, LPS or TBI activated the NF-κB and STAT3 pathways and repressed the PPARγ expression. However, 8-MOP treatment attenuated NF-κB and STAT3 phosphorylation and elevated PPARγ levels. Hence, 8-MOP exerts neuroprotective and anti-inflammatory effects in TBI rats by modulating the PPARγ/NF-κB pathway.
Journal Article
Methoxsalen and Bergapten Prevent Diabetes-Induced Osteoporosis by the Suppression of Osteoclastogenic Gene Expression in Mice
by
Lee, Hae-In
,
Choi, Ra-Yeong
,
Ham, Ju Ri
in
5-Methoxypsoralen - administration & dosage
,
5-Methoxypsoralen - pharmacology
,
Alkaline Phosphatase - metabolism
2019
This study evaluated whether bergapten and methoxsalen could prevent diabetes-induced osteoporosis and its underlying mechanism. For 10 weeks, bergapten or methoxsalen (0.02%, w/w) was applied to diabetic mice that were provided with a high-fat diet and streptozotocin. Bone mineral density (BMD) and microarchitecture quality were significantly reduced in the diabetic control group; however, both bergapten and methoxsalen reversed serum osteocalcin, bone-alkaline phosphatase and femur BMD. These coumarin derivatives significantly increased bone volume density and trabecular number, whereas they decreased the structure model index of femur tissue in diabetic mice. Conversely, tartrate-resistant acid phosphatase 5 (TRAP) staining revealed that these derivatives reduced osteoclast numbers and formation in diabetic bone tissue. Additionally, both bergapten and methoxsalen tended to downregulate the expression of osteoclast-related genes such as receptor activator of nuclear factor kappa-B ligand (RANKL), nuclear of activated T-cells, cytoplasmic 1 (NFATc1) and TRAP in diabetic femurs, with NFATc1 and TRAP expression showing significant reductions. Our data suggest that both bergapten and methoxsalen prevent diabetic osteoporosis by suppressing bone resorption.
Journal Article
Graveoline Analogs Exhibiting Selective Acetylcholinesterase Inhibitory Activity as Potential Lead Compounds for the Treatment of Alzheimer’s Disease
by
Jin, Juan
,
Li, Zeng
,
Mu, Chaoyu
in
acetylcholinesterase (AChE)
,
Acetylcholinesterase - chemistry
,
Acetylcholinesterase - metabolism
2016
This study designed and synthesized a series of new graveoline analogs on the basis of the structural characteristics of acetylcholinesterase (AChE) dual-site inhibitors. The activity of these analogs was also evaluated. Results showed that the synthesized graveoline analogs displayed stronger inhibitory activity against AChE and higher selectivity than butyrylcholine esterase (BuChE) (Selectivity Index from 45 to 486). When the two sites in the graveoline parent ring substituting phenyl and amino terminal had six chemical bonds (n = 3) and the terminal amino was piperidine, compound 5c showed the best activity. Furthermore, the mechanism of action and binding mode were explored by enzyme kinetic simulation, molecular docking, and thioflavin T-based fluorometric assay. Cytotoxicity assay showed that the low concentration of the analogs did not affect the viability of the neurocyte SH-SY5Y.
Journal Article
Structures of human microsomal cytochrome P450 2A6 complexed with coumarin and methoxsalen
by
Hsu, Mei-Hui
,
Stout, C David
,
Griffin, Keith J
in
Aryl Hydrocarbon Hydroxylases - chemistry
,
Aryl Hydrocarbon Hydroxylases - metabolism
,
Biochemistry
2005
Human microsomal cytochrome P450 2A6 (CYP2A6) contributes extensively to nicotine detoxication but also activates tobacco-specific procarcinogens to mutagenic products. The CYP2A6 structure shows a compact, hydrophobic active site with one hydrogen bond donor, Asn297, that orients coumarin for regioselective oxidation. The inhibitor methoxsalen effectively fills the active site cavity without substantially perturbing the structure. The structure should aid the design of inhibitors to reduce smoking and tobacco-related cancers.
Journal Article
Extracorporeal photopheresis (ECP) in the treatment of chronic lung allograft dysfunction (CLAD): a prospective, multicentre, open-label, randomised controlled trial studying the addition of ECP to standard care in the treatment of bilateral lung transplant patients with CLAD (E-CLAD UK)
2024
BackgroundLong-term survival after lung transplantation is limited compared with other organ transplants. The main cause is development of progressive immune-mediated damage to the lung allograft. This damage, which can develop via multiple immune pathways, is captured under the umbrella term chronic lung allograft dysfunction (CLAD). Despite the availability of powerful immunosuppressive drugs, there are presently no treatments proven to reverse or reliably halt the loss of lung function caused by CLAD. The aim of the E-CLAD UK trial is to determine whether the addition of immunomodulatory therapy, in the form of extracorporeal photopheresis (ECP), to standard care is more efficacious at stabilising lung function in CLAD compared with standard care alone.Methods and analysisE-CLAD UK is a Phase II clinical trial of an investigational medicinal product (Methoxsalen) delivered to a buffy coat prepared via an enclosed ECP circuit. Target recruitment is 90 bilateral lung transplant patients identified as having CLAD and being treated at one of the five UK adult lung transplant centres. Participants will be randomised 1:1 to intervention plus standard of care, or standard of care alone. Intervention will comprise nine ECP cycles spread over 20 weeks, each course involving two treatments of ECP on consecutive days. All participants will be followed up for a period of 24 weeks.The primary outcome is lung function stabilisation derived from change in forced expiratory volume in one second and forced vital capacity at 12 and 24 weeks compared with baseline at study entry. Other parameters include change in exercise capacity, health-related quality of life and safety. A mechanistic study will seek to identify molecular or cellular markers linked to treatment response and qualitative interviews will explore patient experiences of CLAD and the ECP treatment.A patient and public advisory group is integral to the trial from design to implementation, developing material to support the consent process and interview materials.Ethics and disseminationThe East Midlands—Derby Research Ethics Committee has provided ethical approval (REC 22/EM/0218). Dissemination will be via publications, patient-friendly summaries and presentation at scientific meetings.Trial registration numberEudraCT number 2022-002659-20; ISRCTN 10615985.
Journal Article
A randomized phase II study of SM‐88 plus methoxsalen, phenytoin, and sirolimus in patients with metastatic pancreatic cancer treated in the second line and beyond
by
Picozzi, Vincent J.
,
Kim, Semmie
,
Van Tornout, Jan M.
in
Adenocarcinoma
,
Adenocarcinoma - pathology
,
Antineoplastic Combined Chemotherapy Protocols - adverse effects
2022
Background This trial explores SM‐88 used with methoxsalen, phenytoin, and sirolimus (MPS) in pretreated metastatic pancreatic ductal adenocarcinoma (mPDAC) Methods Forty‐nine patients were randomized to daily 460 or 920 mg oral SM‐88 with MPS (SM‐88 Regimen). The primary endpoint was objective response rate (RECIST 1.1). Results Thirty‐seven patients completed ≥ one cycle of SM‐88 Regimen (response evaluable population). Disease control rate (DCR), overall survival (OS), and progression‐free survival (PFS) did not differ significantly between dose levels. Stable disease was achieved in 9/37 patients (DCR, 24.3%); there were no complete or partial responses. Quality‐of‐life (QOL) was maintained and trended in favor of 920 mg. SM‐88 Regimen was well tolerated; a single patient (1/49) had related grade 3 and 4 adverse events, which later resolved. In the intention‐to‐treat population of 49 patients, the median overall survival (mOS) was 3.4 months (95% CI: 2.7–4.9 months). Those treated in the second line had an mOS of 8.1 months and a median PFS of 3.8 months. Survival was higher for patients with stable versus progressive disease (any line; mOS: 10.6 months vs. 3.9 months; p = 0.01). Conclusions SM‐88 Regimen has a favorable safety profile with encouraging QOL effects, disease control, and survival trends. This regimen should be explored in the second‐line treatment of patients with mPDAC. ClinicalTrials.gov Identifier: NCT03512756. This trial explores 460 or 920 mg oral SM‐88 daily, used with methoxsalen, phenytoin, and sirolimus (MPS) in previously treated patients with metastatic pancreatic ductal adenocarcinoma (mPDAC). SM‐88 + MPS was well tolerated (1 of 49 patients had drug‐related grade 3/4 adverse events), patient quality‐of‐life was maintained, and overall survival trended toward being better for patients treated in the second (median overall survival [mOS], 8.1 months; median progression‐free survival [mPFS], 3.8 months) versus ≥ third line (mOS, 3.7 months; mPFS, 1.8 months). SM‐88 + MPS should be further explored in the second‐line treatment of patients with mPDAC.
Journal Article
Deciphering the Molecular Mechanisms of Reactive Metabolite Formation in the Mechanism-Based Inactivation of Cytochrome p450 1B1 by 8-Methoxypsoralen and Assessing the Driving Effect of phe268
by
Lamsabhi, Al Mokhtar
,
Kamel, Emadeldin M.
,
Rudayni, Hassan A.
in
8-methoxypsoralen
,
Analysis
,
Binding sites
2024
This study provides a comprehensive computational exploration of the inhibitory activity and metabolic pathways of 8-methoxypsoralen (8-MP), a furocoumarin derivative used for treating various skin disorders, on cytochrome P450 (P450). Employing quantum chemical DFT calculations, molecular docking, and molecular dynamics (MD) simulations analyses, the biotransformation mechanisms and the active site binding profile of 8-MP in CYP1B1 were investigated. Three plausible inactivation mechanisms were minutely scrutinized. Further analysis explored the formation of reactive metabolites in subsequent P450 metabolic processes, including covalent adduct formation through nucleophilic addition to the epoxide, 8-MP epoxide hydrolysis, and non-CYP-catalyzed epoxide ring opening. Special attention was paid to the catalytic effect of residue Phe268 on the mechanism-based inactivation (MBI) of P450 by 8-MP. Energetic profiles and facilitating conditions revealed a slight preference for the C4′=C5′ epoxidation pathway, while recognizing a potential kinetic competition with the 8-OMe demethylation pathway due to comparable energy demands. The formation of covalent adducts via nucleophilic addition, particularly by phenylalanine, and the generation of potentially harmful reactive metabolites through autocatalyzed ring cleavage are likely to contribute significantly to P450 metabolism of 8-MP. Our findings highlight the key role of Phe268 in retaining 8-MP within the active site of CYP1B1, thereby facilitating initial oxygen addition transition states. This research offers crucial molecular-level insights that may guide the early stages of drug discovery and risk assessment related to the use of 8-MP.
Journal Article
Accelerated Development and Toxin Tolerance of the Navel Orangeworm Amyelois transitella (Lepidoptera: Pyralidae) in the Presence of Aspergillus flavus
by
Berenbaum, May R
,
Bush, Daniel S
,
Siegel, Joel P
in
Aspergillus flavus
,
Bioassays
,
Detoxification
2018
The navel orangeworm (Amyelois transitella) and the fungus Aspergillus flavus constitute a facultative mutualism and pest complex in tree nut and fruit orchards in California. The possibility exists that the broad detoxification capabilities of A. flavus benefit its insect associate by metabolizing toxicants, including hostplant phytochemicals and pesticides. We examined this hypothesis by conducting laboratory bioassays to assess growth rates and survivorship of pyrethroid-resistant (R347) and susceptible (CPQ) larval strains on potato dextrose agar diet containing almond meal with and without two furanocoumarins, xanthotoxin and bergapten, found in several hostplants, and with and without two insecticides, bifenthrin and spinetoram, used in almond and pistachio orchards. Additionally, fungi were incubated in liquid diets containing the test chemicals, and extracts of these diets were added to almond potato dextrose agar (PDA) diets and fed to larvae to evaluate the ability of the fungus to metabolize these chemicals. Larvae consuming furanocoumarin-containing diet experienced higher mortality than individuals on unamended diets, but adding A. flavus resulted in up to 61.7% greater survival. Aspergillus flavus in the diet increased development rate > two-fold when furanocoumarins were present, demonstrating fungal enhancement of diet quality. Adding extracts of liquid diets containing xanthotoxin and fungus decreased mortality compared to xanthotoxin alone. On diets containing bifenthrin and spinetoram, however, mortality increased. These results support the hypothesis that A. flavus enhances navel orangeworm performance and contributes to detoxification of xenobiotics. Among practical implications of our findings, this mutualistic association should be considered in designing chemical management strategies for these pests.
Journal Article
Bergapten drives autophagy through the up-regulation of PTEN expression in breast cancer cells
by
Santoro, Marta
,
Andò, Sebastiano
,
Perrotta, Ida
in
Analysis
,
Autophagy - drug effects
,
Autophagy - genetics
2015
Background
Bergapten (5-methoxypsoralen), a natural psoralen derivative present in many fruits and vegetables, has shown antitumoral effects in a variety of cell types. In this study, it has been addressed how Bergapten in breast cancer cells induces autophagic process.
Results
In MCF7 and ZR-75 breast cancer cells Bergapten exhibited anti-survival response by inducing the autophagic process increasing Beclin1, PI3KIII, UVRAG, AMBRA expression and conversion of LC3-I to LC3-II. LC3-GFP, Acridine orange assay and transmission electron microscopy even confirmed the increased autophagosome formations in treated cells. Bergapten-induced autophagy is dependent by PTEN up-regulation, since silencing this gene, the induction of Beclin1 and the p-AKT/p-mTOR signal down-regulation were reversed. PTEN is transcriptionally regulated by Bergapten through the involvement of p38MAPK/NF-Y, as evidenced by the use of p38MAPK inhibitor SB203580, site-direct mutagenesis of NF-Y element and NF-Y siRNA. Furthermore NF-Y knockdown prevented Bergapten-induced acid vesicular organelle accumulations (AVOs), strengthening the role of this element in mediating autophagy.
Conclusions
Our data indicate PTEN as a key target of Bergapten action in breast cancer cells for the induction of autophagy. These findings add further details on the mechanism of action of Bergapten, therefore suggesting that phytochemical compounds may be implemented in the novel strategies for breast cancer treatment.
Journal Article