Journal of Natural Medicines最新文献

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.

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.

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.

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.

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.