Journal of Natural Medicines最新文献

In multicomponent drugs, such as Kampo (traditional Japanese medicine) medicines, compound–compound interactions, including synergistic effects, inhibitory effects, and complex formations, should be considered. Orengedokuto is a Kampo formula, which is used for the treatment of various diseases, including inflammation, hypertension, gastrointestinal disorders, and liver and cerebrovascular diseases. During the decoction process in the production of Orengedokuto, yellow precipitates are obtained from berberine–baicalin complexation; these precipitates enhance the in vivo coprecipitation and coabsorption of both compounds. Scutellaria root contains various baicalin analogs, such as wogonoside, oroxyloside, and scutellarin; however, the compound–compound interactions between berberine and flavonoid glycosides have not been investigated. Herein, we performed precipitation assays for berberine and the crude extract of Scutellaria root to detect and quantify compounds that interact with berberine by HPLC analysis. Furthermore, we performed precipitation assays and NMR experiments to identify chemical structures that affect the formation of precipitates; specifically, we analyzed all combinations of berberine and identified flavonoids to provide insights into associated compound–compound interactions. The NMR experiments indicated that C-8 modification affected the pi–pi interaction between berberine and flavonoids. This information enables the synthesis of more effective molecules and provides insights into their functions, such as drug delivery. The investigation of the interaction mechanisms of berberine and baicalin analogs in Kampo medicines can provide comprehensive insights regarding multicomponent drugs.

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Kampo medicines are widely co-prescribed with Western drugs, yet package inserts typically recommend preprandial dosing. This convention can complicate co-medication schedules and may reduce adherence, while human pharmacokinetic (PK) evidence on meal-timing effects remains limited. We compared pre- versus postprandial administration of maoto to quantify effects on absorption rate and extent for ephedrine and pseudoephedrine. In a two-period, two-sequence crossover, eight healthy adults received ethical maoto extract granules (2.5 g) 30 min before or after a standardized meal. Plasma ephedrine and pseudoephedrine were measured by LC–MS/MS through 24 h. PK was characterized by non-compartmental analysis (NCA) and a pre-specified one-compartment absorption model. The absorption rate constant (k_a) was the mechanistic primary endpoint; AUC quantified extent. Sensitivity (male-only; leave-one-out) and crossover diagnostics (sequence/period) were conducted, and model adequacy was compared by modified Akaike’s Information Criterion (AICc). Preprandial dosing yielded higher C_max, shorter T_max, and larger k_a for both analytes, indicating faster absorption. In contrast, AUC_0–24 h and model-based AUC_∞ were similar between conditions, and k_e did not differ, indicating unchanged extent and disposition. Sensitivity analyses supported these findings; no sequence or period effects were detected. AICc distributions were comparable between conditions. Meal timing primarily alters the absorption rate of ephedrine/pseudoephedrine from maoto without materially changing overall exposure. Preprandial dosing may be preferred when rapid onset is desired, whereas postprandial dosing remains reasonable when adherence and co-medication scheduling are prioritized.

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Naturally occurring compounds like Theobromine, found in tea, coffee, and cocoa, may have anticancer effects. This study explores how Theobromine induces cell death and apoptosis in bladder cancer cells and its impact on NRF2-related gene activity. Two human bladder cancer cell lines—RT112 (non-invasive) and HTB9 (invasive)—were employed. Cell viability was measured using the WST-1 assay, whereas apoptosis and caspase 3/7 activation were determined through flow cytometry. qPCR was performed to measure the expression of NRF2, KEAP1, and P62 genes. Theobromine exhibited a dose-dependent reduction in cell viability in both RT112 and HTB9 bladder cancer cells, while also significantly enhancing apoptosis and caspase 3/7 activity (p<0.0001). Flow cytometry analysis indicated G1-phase arrest in RT112 cells and S-phase accumulation in HTB9 cells following Theobromine treatment, while Cisplatin induced S-phase arrest in both cell lines. Theobromine suppressed NRF2 and P62 while increasing KEAP1 levels in HTB9 cells, suggesting NRF2 pathway inhibition. For RT112 cells, Theobromine upregulated NRF2 and P62 without altering KEAP1 expression, highlighting cell type-specific modulation of the NRF2 signaling pathway. This study shows that Theobromine differentially regulates the Nrf2-Keap1-p62 pathway in bladder cancer cells, inhibiting NRF2 and P62 expression in a cell-specific manner. These findings suggest its potential as a natural anticancer compound, warranting further in vivo studies to assess its therapeutic potential.

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High levels of UV radiation in Okinawa contribute to skin damage, photoaging, and inflammation. Calophyllum inophyllum L. (Tamanu) trees are frequently cultivated along roadways in Okinawa. The oil isolated from Tamanu nuts is renowned for antioxidants, antibacterial, and anti-inflammatory properties. However, the specific UV-absorbing compounds responsible for its anti-inflammatory activity remain unidentified. This study aimed to isolate, characterize, and evaluate the anti-inflammatory activity of UV-absorbing components from Okinawan Tamanu oil. Clinical tests confirmed the UV-protective effects of Tamanu oil, with SPF and PA values of 6.3 ± 0.4 and 2.9 ± 0.6, respectively. UV-absorbing compounds were isolated based on absorbance at 300 nm and structurally characterized by mass spectrometry and NMR. The anti-inflammatory effects of calophyllolide (CAL), inocalophyllin A (ICA), and inocalophyllin B (ICB) were evaluated in LPS-stimulated RAW 264 macrophages and UVB-induced HaCaT keratinocytes. The specific absorbance at 300 nm of CAL, ICA, and ICB isolated from Tamanu oil (300 nm specific absorbance (E_{1cm}^{1% }) = 28) were (E_{1cm}^{1% }) = 695, 285, and 378, respectively. All three compounds significantly inhibited nitric oxide production in LPS-induced RAW 264 cells. CAL downregulated TNF-α, IL-1β, IL-6, and IL-1α, while ICA and ICB suppressed IL-1β, IL-6, and IL-1α. In UVB-stimulated HaCaT cells, all compounds reduced IL-1α production. ICA also suppressed TNF-α, HMGB1, and HDAC2, while ICB downregulated CASP1, BAX, NLRP3, HDAC1, and HDAC2 significantly. These findings suggest that CAL, ICA, and ICB have strong anti-inflammatory properties, with ICA and ICB providing additional protection against UVB-induced skin damage via inhibition of necroptosis and inflammatory signaling.

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This study aims to investigate the mechanism of action of BHLHE40 and its targeted drug, digoxin, in cervical cancer. The clinical significance of BHLHE40 was evaluated in cervical cancer samples using the UALCAN and Human Protein Atlas databases. The effects of BHLHE40 on proliferation, migration, invasion, and epithelial–mesenchymal transition (EMT) were then assessed through loss- and gain-of-function experiments coupled with CCK-8, wound healing, Transwell and Western blot analysis. A murine lung-metastasis model was further established to `validate the pro-metastatic role of BHLHE40 in vivo. JASPAR-based motif prediction, chromatin immunoprecipitation-qPCR (ChIP-qPCR), and luciferase reporter assays were employed to elucidate the transcriptional regulation of ANGPTL3 by BHLHE40. Molecular docking and cellular thermal shift assay (CETSA) were used to clarify the molecular interaction between digoxin and BHLHE40. BHLHE40 was markedly up-regulated in cervical cancer tissues and positively correlated with advanced tumor stage, lymph node metastasis, and poor prognosis. Knockdown of BHLHE40 suppressed proliferation, colony formation, migration, invasion, and attenuated EMT. Consistently, silencing BHLHE40 reduced the number of pulmonary metastatic nodules in nude mice. Mechanistically, BHLHE40 bound directly to the ANGPTL3 promoter and enhanced its transcriptional activity. Knock-down ANGPTL3 reversed BHLHE40-induced increases in migratory and invasive capacities as well as EMT-related phenotypic changes. Digoxin bound to the conserved domain of BHLHE40, down-regulated both BHLHE40 and ANGPTL3, and suppressed EMT and cell motility. Overexpression of BHLHE40 rescued these inhibitory effects of digoxin. Collectively, our findings demonstrate that BHLHE40 promotes EMT and metastasis in cervical cancer by transcriptionally activating ANGPTL3, whereas digoxin exerts anti-EMT effects by targeting this axis. These data highlight the critical role of the BHLHE40-ANGPTL3 axis in cervical cancer progression and suggest that repurposing digoxin offers a novel therapeutic strategy for suppressing EMT in this disease.

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Schematic diagram of BHLHE40/ANGPTL3in CESC. BHLHE40promotes the epithelial-mesenchymal transition of CESCthrough ANGPTL3, andDigoxincan blockthis process by specifically binding to BHLHE40

Rice-derived glucosylceramides (GlcCer) consist of multiple molecules that comprise different types of sphingoid bases and saturated fatty acids. These GlcCer are critical for epidermal barrier function and exert anti-melanogenic effects. Regarding their effects on the immune system, a dead cell-derived GlcCer [d18:2/24:1] was shown to enhance the activation of antigen-presenting cells via Mincle receptors. However, the immunomodulatory effects of rice-derived GlcCer have yet to be examined. Therefore, we herein investigated the effects of rice-derived GlcCer on dendritic cell (DC) activation. Among rice-derived GlcCer, GlcCer[d18:2(4E,8Z)/18:0] (10 μM) significantly enhanced IL-6 production by iMylc DC established from induced pluripotent stem cells. CD40 and CD80 expression was significantly upregulated by GlcCer[d18:2(4E,8Z)/18:0] in aMylc DC derived from human peripheral blood mononuclear cells. In a toll-like receptor (TLR) competitive binding assay using TLR antagonists, GlcCer[d18:2(4E,8Z)/18:0] bound to TLR2 and 4. The antigen-presenting abilities of GlcCer[d18:2(4E,8Z)/18:0] and GlcCer[d18:2(4E,8Z)/26:0] were confirmed by the mixed lymphocyte reaction test, which showed a significant T-cell proliferative effect. These results indicate that GlcCer[d18:2(4E,8Z)/18:0] activated DC being sensed by TLR2 and 4 and induced T-cell responses through the expression of CD40 and CD80. Therefore, the limited GlcCer molecules in rice appear to promote innate immune responses on DC.

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Two new prunasines, bachmasides A and B (1–2), together with five known compounds, methyl 6-O-p-trans-coumaroyl-β-d-glucopyranoside (3), methyl 6-O-feruloyl-β-d-glucopyranoside (4), polystachyol (5), ethyl (6-O-p-hydroxybenzoyl)-β-d-glucopyranoside (6), and prunasin (7) were isolated from leaves of Elaeocarpus bachmaensis. The structures of isolated compounds (1–7) were elucidated by 1D-NMR, 2D-NMR, and HRMS spectra. The inhibition assays showed that compound 5 significantly inhibited α-amylase with IC₅₀ value of 90.2 ± 11.5 µg/ml, whereas compounds 1, 2, 4 and 6 significantly inhibited α-glucosidase with IC₅₀ values ranging from 42.4 ± 5.4 to 75.4 ± 5.6 µg/ml, considerably lower than those of acarbose (IC₅₀ of 112.1 ± 3.1 and 133.0 ± 4.4 µg/ml, respectively). These findings suggest that E. bachmaensis may be a promising source of antidiabetic agents.

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α-Glucosidase and α-amylase are two important glycosidases involved in carbohydrate metabolism. Inhibitors of these enzymes are considered crucial therapeutic agents for carbohydrate absorption disorders such as diabetes and obesity. However, the inhibition of salivary amylase can result in undigested starch reaching the stomach, causing indigestion and potentially leading to gastric and duodenal ulcers as well as gastritis. Selective inhibitors that possess α-glucosidase inhibitory activity without affecting α-amylase are needed to address this issue. It has been revealed that (+)-eupenoxide and its 3-ketone derivative, produced by the endophytic fungus of Aspergillus sp. C-1-1 strain associated with Catharanthus roseus, selectively inhibits α-glucosidase. Additionally, from the α-glucosidase inhibitory activity of related compounds, we have successfully deduced the chemical structure feature necessary for α-glucosidase inhibition.

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Carbazoles exhibit various pharmacological activities, including antitumor activity. Eustifoline-B is a carbazole from Murraya (Rutaceae) plants that exhibited strong antiproliferative activity against cancer stem cells (CSCs) that were established from a human glioblastoma (GBM) cell line (U-251 MG). This activity was stronger than that against GBM cells (non-CSCs), indicating that the activity was CSCs-selective. In this study, the efficacy of carbazole derivatives against GBM was evaluated, their structure–activity relationships were examined, and their blood–brain-barrier (BBB) permeability was investigated in vitro. First, 26 carbazole derivatives, two indole derivatives, and two quinoline derivatives were synthesized, including 12 new compounds. Next, 34 compounds, including the synthesized carbazole derivatives, were evaluated for their antiproliferative activities against U-251 MG CSCs and non-CSCs. Carbazoles with prenyl groups, including eustifoline-B, showed concentration-dependent antiproliferative activity against U-251 MG CSCs (IC₅₀ = 3.5–19.8 µM). Among the prenyl groups, carbazole derivatives with geranyl groups, such as eustifoline-B and eustifoline-C, tended to have stronger activity against CSCs (IC₅₀ = 6.2 µM and 3.5 µM) than that against non-CSCs (IC₅₀ > 25 µM and IC₅₀ = 6.6 µM), indicating that they are CSCs-selective. Finally, in vitro BBB permeability studies were performed using six carbazoles; most carbazoles, including eustifoline-C, exhibited BBB permeability. These results suggest the promising potential of carbazoles as new pharmaceutical agents for the treatment of GBM.

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