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Chemistry (Weinheim An Der Bergstrasse,... Jun 2024Meso-nitrile oxide group in 1,7-Diphenyl-containing BODIPYs can be involved in highly unusual [3+2] intramolecular cycloaddition reaction with the formation of the...
Use of Unprecedented Intramolecular 1, 3-Dipolar Cycloaddition Reaction in meso-Nitrile Oxide-Containing BODIPYs as a New Pathway for the Preparation of Fused NIR Platforms.
Meso-nitrile oxide group in 1,7-Diphenyl-containing BODIPYs can be involved in highly unusual [3+2] intramolecular cycloaddition reaction with the formation of the dihydrobenzo[d]isoxazole-containing BODIPYs. Oxidation of these compounds results in the formation of unprecedented either benzisoxazole- or benzo[b]azepine-fused fully conjugated NIR absorbing BODIPYs. The photophysical properties and electronic structures of the target compounds were studied by an array of experimental and theoretical methods.
PubMed: 38634769
DOI: 10.1002/chem.202401210 -
Journal of Chemical Information and... May 2024Allosteric modulation plays a critical role in enzyme functionality and requires a deep understanding of the interactions between the active and allosteric sites....
Allosteric modulation plays a critical role in enzyme functionality and requires a deep understanding of the interactions between the active and allosteric sites. γ-Secretase (GS) is a key therapeutic target in the treatment of Alzheimer's disease (AD), through its role in the synthesis of amyloid β peptides that accumulate in AD patients. This study explores the structure and dynamic effects of GS modulation by E2012 binding, employing well-tempered metadynamics and conventional molecular dynamics simulations across three binding scenarios: (1) GS enzyme with and without L458 inhibitor, (2) the GS-substrate complex together with the modulator E2012 in two different binding modes, and (3) E2012 interacting with a C99 substrate fragment. Our findings reveal that the presence of L458 induces conformational changes that contribute to stabilization of the GS enzyme dynamics, previously reported as a key factor that allowed the resolution of the cryo-EM structure and the enhanced binding of E2012. Furthermore, we identified the most favorable binding site for E2012 within the GS-substrate complex, uncovering significant modulatory effects and a complex network of interactions that influence the position of the substrate for catalysis. In addition, we explore a potential substrate-modulator binding before the formation of the enzyme-substrate complex. The insights gained from our study emphasize the importance of these interactions in the development of potential therapeutic interventions that target the functionality of the GS enzyme in AD.
Topics: Amyloid Precursor Protein Secretases; Molecular Dynamics Simulation; Substrate Specificity; Protein Binding; Humans; Protein Conformation; Allosteric Regulation; Alanine; Azepines
PubMed: 38623052
DOI: 10.1021/acs.jcim.3c01993 -
American Journal of Physiology.... Jun 2024Inhibition of the bromodomain and extraterminal domain (BET) protein family is a potential strategy to prevent and treat diabetes; however, the clinical use of BET...
Inhibition of the bromodomain and extraterminal domain (BET) protein family is a potential strategy to prevent and treat diabetes; however, the clinical use of BET bromodomain inhibitors (BETis) is associated with adverse effects. Here, we explore a strategy for targeting BETis to β cells by exploiting the high-zinc (Zn) concentration in β cells relative to other cell types. We report the synthesis of a novel, Zn-chelating derivative of the pan-BETi (+)-JQ1, (+)-JQ1-DPA, in which (+)-JQ1 was conjugated to dipicolyl amine (DPA). As controls, we synthesized (+)-JQ1-DBA, a non-Zn-chelating derivative, and (-)-JQ1-DPA, an inactive enantiomer that chelates Zn. Molecular modeling and biophysical assays showed that (+)-JQ1-DPA and (+)-JQ1-DBA retain potent binding to BET bromodomains in vitro. Cellular assays demonstrated (+)-JQ1-DPA attenuated NF-ĸB target gene expression in β cells stimulated with the proinflammatory cytokine interleukin 1β. To assess β-cell selectivity, we isolated islets from a mouse model that expresses green fluorescent protein in insulin-positive β cells and mTomato in insulin-negative cells (non-β cells). Surprisingly, Zn chelation did not confer β-cell selectivity as (+)-JQ1-DPA was equally effective in both β and α cells; however, (+)-JQ1-DPA was less effective in macrophages, a nonendocrine islet cell type. Intriguingly, the non-Zn-chelating derivative (+)-JQ1-DBA displayed the opposite selectivity, with greater effect in macrophages compared with (+)-JQ1-DPA, suggesting potential as a macrophage-targeting molecule. These findings suggest that Zn-chelating small molecules confer endocrine cell selectivity rather than β-cell selectivity in pancreatic islets and provide valuable insights and techniques to assess Zn chelation as an approach to selectively target small molecules to pancreatic β cells. Inhibition of BET bromodomains is a novel potential strategy to prevent and treat diabetes mellitus. However, BET inhibitors have negative side effects. We synthesized a BET inhibitor expected to exploit the high zinc concentration in β cells to accumulate in β cells. We show our inhibitor targeted pancreatic endocrine cells; however, it was less effective in immune cells. A control inhibitor showed the opposite effect. These findings help us understand how to target specific cells in diabetes treatment.
Topics: Animals; Zinc; Chelating Agents; Insulin-Secreting Cells; Mice; Transcription Factors; Triazoles; Humans; Male; Azepines; Glucagon-Secreting Cells; Mice, Inbred C57BL; Bromodomain Containing Proteins; Nuclear Proteins
PubMed: 38618911
DOI: 10.1152/ajpregu.00259.2023 -
Neurologia May 2024In the present study, anticonvulsant effects of aqueous extract (AE), hydro-alcoholic crude extract (HE), and its fractions (F-CHCl, F-EtOAc, F-MeOH) of Paeonia daurica...
INTRODUCTION
In the present study, anticonvulsant effects of aqueous extract (AE), hydro-alcoholic crude extract (HE), and its fractions (F-CHCl, F-EtOAc, F-MeOH) of Paeonia daurica subsp. macrophylla (P. daurica ssp. macrophylla) root examined by using a pentylenetetrazol-induced model (PTZ) on mice.
METHODS
HE and its fractions as well as AE, in concentrations of (100, 200 and 400mg/kg), valproate (Val) (100 and 200mg/kg), and saline (negative control) (10mg/kg) were injected intraperitoneally (i.p.) 30min before PTZ (80mg/kg, i.p.). The time taken before the onset of myoclonic convulsions (MC), MC duration, time taken before the onset of generalized tonic-clonic seizures (GTCS), the duration of GTCS, and the percentage of GTCS and mortality protection recorded. The plant's anticonvulsant mechanisms were assessed using flumazenil (5mg/kg, i.p.) before AE (100, 200, and 400mg/kg, i.p.) injection. GraphPad Prism software was used to compare the differences between various treatment groups with one-way analysis of variance (ANOVA) followed by Tukey-Krammer multiple comparison tests.
RESULTS
All the plant samples except F-EtOAc significantly delayed the onset and decreased the duration of PTZ-induced MCS and GTCS, and significantly reduced the GTCS and mortality rate. Pretreatment with flumazenil diminished the significant anticonvulsant effects of AE against PTZ-induced seizures.
CONCLUSIONS
It can report that extract of P. daurica ssp. macrophylla might be a helpful guide for future studies in the treatment of epilepsy.
Topics: Animals; Mice; Anticonvulsants; Pentylenetetrazole; Paeonia; Flumazenil; Seizures
PubMed: 38616060
DOI: 10.1016/j.nrleng.2021.08.004 -
International Journal of Molecular... Mar 2024This study presents the synthesis of four series of novel hybrid chalcones ()- and ()- and six series of 1,3,5-triazine-based pyrimido[4,5-][1,4]diazepines (-)- and the...
Synthesis of Novel Triazine-Based Chalcones and 8,9-dihydro-7-pyrimido[4,5-][1,4]diazepines as Potential Leads in the Search of Anticancer, Antibacterial and Antifungal Agents.
This study presents the synthesis of four series of novel hybrid chalcones ()- and ()- and six series of 1,3,5-triazine-based pyrimido[4,5-][1,4]diazepines (-)- and the evaluation of their anticancer, antibacterial, antifungal, and cytotoxic properties. Chalcones ,, ,, ,-, - and the pyrimido[4,5-][1,4]diazepines ,, , ,,-, ,,- exhibited outstanding anticancer activity against a panel of 60 cancer cell lines with GI values between 0.01 and 100 μM and LC values in the range of 4.09 μM to >100 μM, several of such derivatives showing higher activity than the standard drug 5-fluorouracil (5-FU). On the other hand, among the synthesized compounds, the best antibacterial properties against , (ATCC 43300), and were exhibited by the pyrimido[4,5-][1,4]diazepines (MICs: 0.25-62.5 µg/mL). The antifungal activity studies showed that triazinylamino-chalcone and triazinyloxy-chalcone were the most active compounds against and and , respectively (MICs = 62.5 μg/mL). Hemolytic activity studies and in silico toxicity analysis demonstrated that most of the compounds are safe.
Topics: Chalcones; Antifungal Agents; Staphylococcus aureus; Anti-Bacterial Agents; Azepines; Fluorouracil; Mycobacterium tuberculosis; Neisseria gonorrhoeae; Triazines; Isocyanates
PubMed: 38612435
DOI: 10.3390/ijms25073623 -
The Journal of Organic Chemistry May 2024An oxidative cascade iodocyclization of 1,7- or 1,8-dienes has been realized under mild conditions. By employing I as an iodine source, this protocol provides a concise...
An oxidative cascade iodocyclization of 1,7- or 1,8-dienes has been realized under mild conditions. By employing I as an iodine source, this protocol provides a concise and efficient approach to a great deal of biologically significant iodinated benzo[]azepine and benzo[]azocine derivatives in moderate to good yields. The gram-scale synthesis and further transformation of products render the approach practical and attractive. Radical trapping and deuterium-labeling experiments help to understand the mechanism.
PubMed: 38603543
DOI: 10.1021/acs.joc.4c00438 -
Nan Fang Yi Ke Da Xue Xue Bao = Journal... Mar 2024To explore the inhibitory effect of saikosonin a (SSa) on pentylenetetrazol-induced acute epilepsy seizures in a mouse model of depression and explore the mechanism...
OBJECTIVE
To explore the inhibitory effect of saikosonin a (SSa) on pentylenetetrazol-induced acute epilepsy seizures in a mouse model of depression and explore the mechanism mediating this effect.
METHODS
Male C57BL/6J mouse models of depression was established by oral administration of corticosterone drinking water for 3 weeks, and acute epileptic seizures were induced by intraperitoneal injection of a single dose of pentylenetetrazole. The effect of intraperitoneal injection of SSa prior to the treatment on depressive symptoms and epileptic seizures were assessed using behavioral tests, epileptic seizure grading and hippocampal morphology observation. ELISA was used to detect blood corticosterone levels of the mice, and RTqPCR was performed to detect the pro- and anti-inflammatory factors. Microglia activation in the mice was observed using immunofluorescence staining.
RESULTS
The mouse model of corticosterone-induced depression showed body weight loss and obvious depressive behaviors with significantly increased serum corticosterone level (all < 0.05). Compared with those with pentylenetetrazole-induced epilepsy alone, the epileptic mice with comorbid depression showed significantly shorter latency of epileptic seizures, increased number, grade and duration of of seizures, reduced Nissl bodies in hippocampal CA1 and CA3 neurons, increased number of Iba1-positive cells, and significantly enhanced hippocampal expressions of IL-1β, IL-10, TNF-α and IFN-γ. Pretreatment of the epileptic mice with SSa significantly prolonged the latency of epileptic seizures, reduced the number, duration, and severity of seizures, increased the number of Nissl bodies, decreased the number of Iba1-positive cells, and reduced the expression levels of IL-1β, IL-10, TNF-α, and IFN-γ in the hippocampus ( < 0.05).
CONCLUSION
Depressive state aggravates epileptic seizures, increases microglia activation, and elevates inflammation levels. SSA treatment can alleviate acute epileptic seizures in mouse models of depression possibly by suppressing microglia activation-mediated inflammation.
Topics: Male; Mice; Animals; Pentylenetetrazole; Interleukin-10; Microglia; Tumor Necrosis Factor-alpha; Depression; Corticosterone; Mice, Inbred C57BL; Seizures; Epilepsy; Hippocampus; Inflammation; Interleukin-1beta; Disease Models, Animal; Oleanolic Acid; Saponins
PubMed: 38597443
DOI: 10.12122/j.issn.1673-4254.2024.03.13 -
Pesticide Biochemistry and Physiology Mar 2024To explore active natural products against tobacco powdery mildew caused by Golovinomyces cichoracearum, an extract from the fermentation of endophytic Aspergillus...
To explore active natural products against tobacco powdery mildew caused by Golovinomyces cichoracearum, an extract from the fermentation of endophytic Aspergillus fumigatus 0338 was investigated. The mechanisms of action for active compounds were also studied in detail. As a result, 14 indole alkaloid derivatives were isolated, with seven being newly discovered (1-7) and the remaining seven previously described (8-14). Notably, compounds 1-3 are rare linearly fused 6/6/5 tricyclic prenylated indole alkaloids, with asperversiamide J being the only known natural product of this kind. The isopentenyl substitutions at the 5-position in compounds 4 and 5 are also rare, with only compounds 1-(5-prenyl-1H-indol-3-yl)-propan-2-one (8) and 1-(6-methoxy-5-prenyl-1H-indol3-yl)-propan-2-one currently available. In addition, compounds 6 and 7 are new framework indole alkaloid derivatives bearing a 6-methyl-1,7-dihydro-2H-azepin-2-one ring. The purified compounds were evaluated for their activity against G. cichoracearum, and the results revealed that compounds 7 and 9 demonstrated obvious anti-G. cichoracearum activities with an inhibition rate of 82.6% and 85.2%, respectively, at a concentration of 250 μg/mL, these rates were better than that of the positive control agent, carbendazim (78.6%). The protective and curative effects of compounds 7 and 9 were also better than that of positive control, at the same concentration. Moreover, the mechanistic study showed that treatment with compound 9 significantly increased the structural tightness of tobacco leaves and directly affect the conidiospores of G. cichoracearum, thereby enhancing resistance. Compounds 7 and 9 could also induce systemic acquired resistance (SAR), directly regulating the expression of defense enzymes, defense genes, and plant semaphorins, which may further contribute to increased plant resistance. Based on the activity experiments and molecular dockings, the indole core structure may be the foundation of these compounds' anti-G. cichoracearum activity. Among them, the indole derivative parent structures of compounds 6, 7, and 9 exhibit strong effects. Moreover, the methoxy substitution in compound 7 can enhance their activity. By isolating and structurally identifying the above indole alkaloids, new candidates for anti-powdery mildew chemical screening were discovered, which could enhance the utilization of N. tabacum-derived fungi in pesticide development.
Topics: Aspergillus fumigatus; Nicotiana; Indole Alkaloids; Alkaloids; Neoprene
PubMed: 38582586
DOI: 10.1016/j.pestbp.2024.105814 -
Behavioural Brain Research May 2024This study verified the effects of the natural compounds berberine and hesperidin on seizure development and cognitive impairment triggered by pentylenetetrazole (PTZ)...
This study verified the effects of the natural compounds berberine and hesperidin on seizure development and cognitive impairment triggered by pentylenetetrazole (PTZ) in zebrafish. Adult animals were submitted to a training session in the inhibitory avoidance test and, after 10 minutes, they received an intraperitoneal injection of 25, 50, or 100 mg/kg berberine or 100 or 200 mg/kg hesperidin. After 30 minutes, the animals were exposed to 7.5 mM PTZ for 10 minutes. Animals were submitted to the test session 24 h after the training session to verify their cognitive performance. Zebrafish larvae were exposed to 100 µM or 500 µM berberine or 10 µM or 50 µM hesperidin for 30 minutes. After, larvae were exposed to PTZ and had the seizure development evaluated by latency to reach the seizure stages I, II, and III. Adult zebrafish pretreated with 50 mg/kg berberine showed a longer latency to reach stage III. Zebrafish larvae pretreated with 500 µM berberine showed a longer latency to reach stages II and III. Hesperidin did not show any effect on seizure development both in larvae and adult zebrafish. Berberine and hesperidin pretreatments prevented the memory consolidation impairment provoked by PTZ-induced seizures. There were no changes in the distance traveled in adult zebrafish pretreated with berberine or hesperidin. In larval stage, berberine caused no changes in the distance traveled; however, hesperidin increased the locomotion. Our results reinforce the need for investigating new therapeutic alternatives for epilepsy and its comorbidities.
Topics: Animals; Zebrafish; Pentylenetetrazole; Berberine; Hesperidin; Seizures; Avoidance Learning; Memory Consolidation; Memory Disorders; Male; Disease Models, Animal; Convulsants; Larva; Dose-Response Relationship, Drug; Anticonvulsants
PubMed: 38580198
DOI: 10.1016/j.bbr.2024.114981 -
Current Pharmaceutical Design 2024Spinal Muscular Atrophy (SMA) is a severe motor neuronal disorder with high morbidity and mortality. Securinine has shown the potential to treat SMA; however, its...
BACKGROUND
Spinal Muscular Atrophy (SMA) is a severe motor neuronal disorder with high morbidity and mortality. Securinine has shown the potential to treat SMA; however, its anti-SMA role remains unclear.
OBJECTIVE
This study aims to reveal the anti-SMA mechanisms of securinine.
METHODS
Securinine-associated targets were acquired from Herbal Ingredients' Targets (HIT), Similarity Ensemble Approach (SEA), and SuperPred. SMA-associated targets were obtained from GeneCards and Dis- GeNET. Protein-protein Interaction (PPI) network was constructed using GeneMANIA, and hug targets were screened using cytoHubba. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed using ClusterProfifiler. Molecular docking was conducted using Pymol and Auto- Dock. In vitro assays were used to verify the anti-SMA effects of securinine.
RESULTS
Twenty-six intersection targets of securinine and SMA were obtained. HDAC1, HDAC2, TOP2A, PIK3R1, PRMT5, JAK2, HSP90AB1, TERT, PTGS2, and PAX8 were the core targets in PPI network. GO analysis demonstrated that the intersecting targets were implicated in the regulation of proteins, steroid hormones, histone deacetylases, and DNA transcription. KEGG analysis, pathway-pathway, and hub target-pathway networks revealed that securinine might treat SMA through TNF, JAK-STAT, Ras, and PI3K-Akt pathways. Securinine had a favorable binding affinity with HDAC1, HSP90AB, JAK2, PRMT5, PTGS2, and TERT. Securinine rescued viability suppression, mitochondria damage, and SMN loss in the SMA cell model. Furthermore, securinine increased HDAC1 and PRMT5 expression, decreased PTGS2 expression, suppressed the JAK2-STAT3 pathway, and promoted the PI3K-Akt pathway.
CONCLUSION
Securinine might alleviate SMA by elevating HDAC1 and PRMT5 expression and reducing PTGS2 via JAK2-STAT3 suppression and PI3K-Akt activation.
Topics: Network Pharmacology; Muscular Atrophy, Spinal; Humans; Plants, Medicinal; Molecular Docking Simulation; Azepines; Lactones; Molecular Structure; Heterocyclic Compounds, Bridged-Ring; Piperidines
PubMed: 38561613
DOI: 10.2174/0113816128288504240321041408