In vitro and in silico studies of 7'',8''-buddlenol D anti-inflammatory lignans from Carallia brachiata as p38 MAP kinase inhibitors

Discovery of soluble epoxide hydrolase inhibitors from Inula britannica: Inhibition kinetics, molecular dynamics simulation, biochemical, and in vitro cell-based studies

Soluble epoxide hydrolase (sEH) is an enzyme involved in transforming epoxyeicosatrienoic acids (EETs) to dihydroxyeicosatrienoic acids (DHETs). EETs play a pivotal role in maintaining anti-inflammatory response and pain regulation, making sEH as an important target for therapeutic interventions. Based on our present study of discovery of sEH inhibitors, herein, six new (1-6) and fifteen known compounds (7-21) with inhibitory effects toward sEH were isolated from Inula britannica. Among them, compounds 5 (inulabritanthymol G) and 9 (bellidtfolin) possessed strongest inhibitory abilities with IC50 values of 3.87 and 2.85 μM, respectively. Inhibition kinetics indicated that they were assigned as uncompetitive inhibitors, and their Ki values were 1.93 and 1.89 μM, respectively. Molecular dynamics simulation demonstrated that the stability and interactions of inhibitors 5/9 with sEH were attributed to hydrogen bonds with amino acid residues of Asp335, Ser374, or Asn472. In addition, inhibitors 5 and 9 could exert anti-inflammatory effects through suppressing the NF-κB activation in LPS-exposed RAW264.7 cells, highlighting their potential as natural therapeutic agents for managing inflammatory diseases.

Maeruines A-E, elusive indole alkaloids from stems of Maerua siamensis and their inhibitory effects on cyclooxygenases and HT-29 colorectal cancer cell proliferation

Five previously undescribed indole alkaloids, maeruines A-E (1-5), bearing imino-2H-thieno[2,3-b]indol-3(8H)-one skeleton, were obtained from the stems of Maerua siamensis. Their chemical structures were elucidated using spectroscopic techniques [NMR, MS, IR, and UV], and single-crystal X-ray diffraction. Maeruine D (4) displayed selective cyclooxygenase-2 (COX-2) inhibitory activity in vitro with an IC50 of 29.72 ± 6.36 μM. Molecular dynamics simulations revealed that maeruine D could form a stable complex with human COX-2, predominantly driven by hydrophobic interactions. In addition, five amino-acid residues including Val349, Leu352, Leu384, Val523, and Ala527 were identified as hot-spot ones, which may lead to high binding affinity and selectivity. Furthermore, it exhibited cytotoxicity against HT-29 colorectal cancer cells with an IC50 of 29.32 ± 4.76 μM, and, at 0.1-10 μM, significantly inhibited their proliferation, induced by the proinflammatory cytokine interleukin-1β (IL-1β), in a dose-dependent manner.

Repurposing FDA-approved drugs targeting FZD10 in nasopharyngeal carcinoma: insights from molecular dynamics simulations and experimental validation

Wnt signaling is a critical pathway implicated in cancer development, with Frizzled proteins, particularly FZD10, playing key roles in tumorigenesis and recurrence. This study focuses on the potential of repurposed FDA-approved drugs targeting FZD10 as a therapeutic strategy for nasopharyngeal carcinoma (NPC). The tertiary structure of human FZD10 was constructed using homology modeling, validated by Ramachandran plot and ProQ analysis. Virtual screening of 1,094 FDA-approved drugs identified 17 potential inhibitors, with prazosin, rilpivirine, doxazosin, and nicergoline demonstrating significant cytotoxicity against NPC cells. Further molecular dynamics simulations and binding energy analyses confirmed the stable binding of these drugs to FZD10. The results suggest that these repurposed drugs could serve as promising candidates for targeted NPC therapy, warranting further investigation.

Polymeric scaffold integrated with nanovesicle-entrapped curcuminoids for enhanced therapeutic efficacy

Aim: Polymeric scaffolds were developed fortified with nanovesicle-encapsulated individual curcumin (CUR) and tetrahydrocurcumin (THC) for improved therapeutic efficacy due to their low stability and efficacy in native form. Method: Nanovesicle-encapsulated individual CUR and THC were fabricated using thin-film hydration techniques and characterized. Results & conclusion: CUR/THC in native and vesicle-encapsulated form demonstrated diminished LPS-instigate nitric oxide (NO) levels in macrophage cells in a concentration-dependent demeanor. However, vesicle-encapsulated CUR/THC inhibited NO production at lower concentrations, compared with the native CUR/THC form. Furthermore, the scaffold fortified with vesicle-encapsulated CUR/THC demonstrated improved physical properties with excellent antioxidant, biocompatibility, and human keratinocyte cell proliferation ability. The results recommended that nanovesicle-encapsulated THC can be retained as a potential substitute for CUR with improved therapeutic efficacy.

Eight structurally diverse components with anti-acetylcholinesterase activity from Daphne bholua

Eight structurally diverse components, including six undescribed ones, (±)-daphuarin A (1a/1b), daphuarin B (2), daphuarin D-E (4-6), together with a pair of new natural products (±)-daphuarin C (3a/3b) were isolated from the herb of Daphne bholua Buch.-Ham. ex D. Don. Their planar structures were elucidated by extensive spectroscopic analyses. The configurations were established with the assistance of quantum chemical calculations, together with the Custom DP4+ method. The inhibitory potentials of all isolates against acetylcholinesterase were evaluated.

Regulation of neuroinflammation in Alzheimer's disease via nanoparticle-loaded phytocompounds with anti-inflammatory and autophagy-inducing properties

BACKGROUND

Alzheimer's disease (AD) is characterized by neuroinflammation linked to amyloid β (Aβ) aggregation and phosphorylated tau (τ) protein in neurofibrillary tangles (NFTs). Key elements in Aβ production and NFT assembly, like γ-secretase and p38 mitogen-activated protein kinase (p38MAPK), contribute to neuroinflammation. In addition, impaired proteosomal and autophagic pathways increase Aβ and τ aggregation, leading to neuronal damage. Conventional neuroinflammation drugs have limitations due to unidirectional therapeutic approaches and challenges in crossing the Blood-Brain Barrier (BBB). Clinical trials for non-steroidal anti-inflammatory drugs (NSAIDs) and other therapeutics remain uncertain. Novel strategies addressing the complex pathogenesis and BBB translocation are needed to effectively tackle AD-related neuroinflammation.

PURPOSE

The current scenario demands for a much-sophisticated theranostic measures which could be achieved via customized engineering and designing of novel nanotherapeutics. As, these therapeutics functions as a double edge sword, having the efficiency of unambiguous targeting, multiple drug delivery and ability to cross BBB proficiently.

METHODS

Inclusion criteria involve selecting recent, English-language studies from the past decade (2013-2023) that explore the regulation of neuroinflammation in neuroinflammation, Alzheimer's disease, amyloid β, tau protein, nanoparticles, autophagy, and phytocompounds. Various study types, including clinical trials, experiments, and reviews, were considered. Exclusion criteria comprised non-relevant publication types, studies unrelated to Alzheimer's disease or phytocompounds, those with methodological flaws, duplicates, and studies with inaccessible data.

RESULTS

In this study, polymeric nanoparticles loaded with specific phytocompounds and coated with an antibody targeting the transferrin receptor (anti-TfR) present on BBB. Thereafter, the engineered nanoparticles with the ability to efficiently traverse the BBB and interact with target molecules within the brain, could induce autophagy, a cellular process crucial for neuronal health, and exhibit potent anti-inflammatory effects. Henceforth, the proposed combination of desired phytocompounds, polymeric nanoparticles, and anti-TfR coating presents a promising approach for targeted drug delivery to the brain, with potential implications in neuroinflammatory conditions such as Alzheimer's disease.