Phytochemical Investigation of Equisetum arvense and Evaluation of Their Anti-Inflammatory Potential in TNFα/INFγ-Stimulated Keratinocytes.

Equisetum arvense L. (Equisetaceae), widely known as 'horsetail', is a perennial plant found extensively across Asia. Extracts of E. arvense have been used in traditional medicine, particularly for the treatment of inflammatory disorders. This study aimed to determine the phytochemical compounds in E. arvense ethanolic extract and their anti-inflammatory properties. Subsequently, we isolated and identified nine secondary metabolites, including kaempferol 3,7-di-O-ß-D-glucopyranoside (1), icariside B2 (2), (Z)-3-hexenyl ß-D-glucopyranoside (3), luteolin 5-O-ß-D-glucopyranoside (4), 4-O-ß-D-glucopyranosyl caffeic acid (5), clemastanin B (6), 4-O-caffeoylshikimic acid (7), (7S,8S)-threo-7,9,9'-trihydroxy-3,3'-dimethoxy-8-O-4'-neolignan-4-O-ß-D-glucopyranoside (8), and 3-O-caffeoylshikimic acid (9). The chemical structures of the isolated compounds (1-9) were elucidated using HR-ESI-MS data, NMR spectra, and ECD data. Next, the anti-inflammatory effects of the isolates were evaluated in tumor necrosis factor (TNF)α/interferon (IFN)γ-induced HaCaT, a human keratinocyte cell line. Among the isolates, compound 3 showed the highest inhibitory effect on the expression of pro-inflammatory chemokines, followed by compounds 6 and 8. Correspondingly, the preceding isolates inhibited TNFα/IFNγ-induced activation of pro-inflammatory transcription factors, signal transducer and activator of transcription 1, and nuclear factor-κB. Collectively, E. arvense could be employed for the development of prophylactic or therapeutic agents for improving dermatitis.

Anti-Adipogenic Effects of Salicortin from the Twigs of Weeping Willow (Salix pseudolasiogyne) in 3T3-L1 Cells.

Salix pseudolasiogyne (Salicaceae), the "weeping willow," has been used in traditional Korean medicine to treat pain and fever due to its high concentrations of salicylic acid and salicin. The present study investigated bioactive compounds from S. pseudolasiogyne twigs to discover bioactive natural products. Phytochemical investigation of the ethanol (EtOH) extract of S. pseudolasiogyne twigs followed by liquid chromatography-mass spectrometry (LC/MS)-based analysis led to the isolation of two salicin derivatives, salicortinol and salicortin, the structures of which were determined by interpretation of their NMR spectra and data from the LC/MS analysis. To the best of our knowledge, this is the first report of salicortinol isolated from S. pseudolasiogyne. The isolated compounds were evaluated for their anti-adipogenic effects in 3T3-L1 cells. Both salicortinol and salicortin were found to significantly inhibit adipocyte differentiation in 3T3-L1 cells. In particular, salicortin exhibited a strong inhibitory effect on lipid accumulation. Furthermore, salicortin inhibited the expression of lipogenic and adipogenic transcription factors, including FASN, FABP4, C/EBPα, C/EBPß, and PPARγ, without inducing cytotoxicity. These results suggest that salicortin could be a potential therapeutic compound for the prevention or treatment of metabolic disorders such as obesity.

Bioactive Phytochemicals from Salix pseudolasiogyne Twigs: Anti-Adipogenic Effect of 2'-O-Acetylsalicortin in 3T3-L1 Cells.

Salix pseudolasiogyne (Salicaceae) is a willow tree and has been used as a medicinal herb in Korea to treat pain and fever. As a part of an ongoing study to identify bioactive natural products, potential anti-adipogenic compounds were investigated using the ethanol (EtOH) extract of S. pseudolasiogyne twigs. Phytochemical investigation of the EtOH extracts using liquid chromatography-mass spectrometry (LC/MS) led to the separation of two compounds, oregonin (1) and 2'-O-acetylsalicortin (2). The structures of the isolates were identified using nuclear magnetic resonance spectroscopy and LC/MS analysis. To the best of our knowledge, it is the first report identifying oregonin (1) in twigs of S. pseudolasiogyne. Here, we found that the isolated compounds, oregonin (1) and 2'-O-acetylsalicortin (2), showed anti-adipogenic effects during 3T3-L1 cell differentiation. Notably, 2'-O-acetylsalicortin (2), at a concentration of 50 µM, significantly suppressed lipid accumulation. Moreover, the mRNA and protein levels of lipogenic and adipogenic transcription factors were reduced in 2'-O-acetylsalicortin (2)-treated 3T3-L1 cells. Taken together, these results indicate that 2'-O-acetylsalicortin (2), isolated from S. pseudolasiogyne twigs, has the potential to be applied as a therapeutic agent to effectively control adipocyte differentiation, a critical stage in the progression of obesity.

Suppression of 6-Hydroxydopamine-Induced Oxidative Stress by Hyperoside Via Activation of Nrf2/HO-1 Signaling in Dopaminergic Neurons.

In our ongoing research to discover natural products with neuroprotective effects, hyperoside (quercetin 3-O-galactoside) was isolated from Acer tegmentosum, which has been used in Korean traditional medicine to treat liver-related disorders. Here, we demonstrated that hyperoside protects cultured dopaminergic neurons from death via reactive oxygen species (ROS)-dependent mechanisms, although other relevant mechanisms of hyperoside activity remain largely uncharacterized. For the first time, we investigated the neuroprotective effects of hyperoside on 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in neurons, and the possible underlying mechanisms. Hyperoside significantly ameliorated the loss of neuronal cell viability, lactate dehydrogenase release, excessive ROS accumulation and mitochondrial membrane potential dysfunction associated with 6-OHDA-induced neurotoxicity. Furthermore, hyperoside treatment activated the nuclear erythroid 2-related factor 2 (Nrf2), an upstream molecule of heme oxygenase-1 (HO-1). Hyperoside also induced the expression of HO-1, an antioxidant response gene. Remarkably, we found that the neuroprotective effects of hyperoside were weakened by an Nrf2 small interfering RNA, which blocked the ability of hyperoside to inhibit neuronal death, indicating the vital role of HO-1. Overall, we show that hyperoside, via the induction of Nrf2-dependent HO-1 activation, suppresses neuronal death caused by 6-OHDA-induced oxidative stress. Moreover, Nrf2-dependent HO-1 signaling activation represents a potential preventive and therapeutic target in Parkinson's disease management.

Standardized Cirsium setidens Nakai Ethanolic Extract Suppresses Adipogenesis and Regulates Lipid Metabolisms in 3T3-L1 Adipocytes and C57BL/6J Mice Fed High-Fat Diets.

Cirsium setidens Nakai, a wild perennial herb, grows mainly in Gangwon province, Korea, and has been reported to contain bioactive ingredients with various medicinal activities, including the treatment of edema, bleeding, and hemoptysis. However, the potential antiobesity effects of C. setidens Nakai have not been fully investigated. This study evaluated the antiobesity effect of standardized C. setidens Nakai ethanolic extract (CNE) in 3T3-L1 adipocytes and in obese C57BL/6J mice fed a high-fat diet. CNE suppressed the expression of lipogenic genes and increased the expression of lipolytic genes. The antiadipogenic and antilipogenic effects of CNE appear to be mediated by the inhibition of peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein (C/EBP) expressions. Moreover, CNE stimulated fatty acid oxidation in an AMPK-dependent manner. CNE-treated groups of C57BL/6J mice showed reduced body weights and adipose tissue weight and improved serum lipid profiles through the downregulation of PPARγ, C/EBPα, fatty acid binding protein 4 (FABP4), sterol regulatory element binding protein-1c (SREBP-1c), and fatty acid synthase (FAS) and the upregulation of adiponectin and carnitine palmitoyltransferase-1 (CPT-1) in obese C57BL/6J mice fed a high-fat diet. These results suggest that CNE may have an antiobesity effect on adipogenesis and lipid metabolism in vitro and in vivo and present the possibility of developing a treatment for obesity with nontoxic natural resources.

Pinecone of Pinus koraiensis Inducing Apoptosis in Human Lung Cancer Cells by Activating Caspase-3 and its Chemical Constituents.

Pinecones from Pinus koraiensisSiebold & Zucc. (Pinaceae), which have historically been treated as an undesired waste by-product in the processing of seeds, have recently been shown to contain ingredients with potent biological activities, such as polyphenols exhibiting antitumor activity. With this study, we seek to broaden our understanding of antitumor compounds contained in these pinecones beyond just polyphenols. We found that the water extract of P. koraiensis pinecones exhibits significant cytotoxic activity, with IC50 values ranging from 0.62 to 1.73 mg/ml in four human lung cancer cell lines, A549, H1264, H1299, and Calu-6, irrespective of their p53 status. We also demonstrate that pinecone water extract induces apoptosis associated with caspase-3 activation in the same cancer cell lines. Chemical investigation of the pinecone water extract revealed eight main components (1 - 8), and their structures were identified as dehydroabietic acid (1), 15-hydroxy-7-oxodehydroabietic acid (2), 7ß,15-dihydroxydehydroabietic acid (3), ß-d-glucopyranosyl labda-8(17,13)-diene-(15,16)-lactone-19-oate (4), 7α,15-dihydroxydehydroabietic acid (5), (+)-(1S,2S,4R)-limonene-1,2-diol (6), sobrerol (7), and 4-hydroxybenzoic acid (8). These findings suggest a novel biological application of P. koraiensis pinecones in combatting human lung cancer, and further identify the major compounds that could contribute to this anticancer activity.