Glaucatotones A-I: Guaiane-type sesquiterpenoids from the roots of Lindera glauca with anti-inflammatory activity.

Glaucatotones A - I, nine new guaiane-type sesquiterpenoids, along with two reported compounds, namely (1ß,5ß)-1-hydroxyguaia-4(15),11(13)-dieno-12,5-lactone (10) and pseudoguaianelactone C (11), were isolated from the roots of Lindera glauca. The structures and absolute configurations of these compounds were elucidated by extensive spectroscopic analyses, single-crystal X-ray diffraction, and comparison of experimental and calculated electronic circular dichroism (ECD) data. Structurally, glaucatotone A (1) is characterized as a dihomosesquiterpenoid with an unprecedented 5/5/7/6 ring system. A pair of enantiomers, (±)-glaucatotone B (2a/2b), represent the first rearranged norsesquiterpenoid with a (cyclopentylmethyl)cyclohexane skeleton. 3 is defined as a dinorsesquiterpenoid possessing a 5/7/5 ring system. 4-6 are three guaiane-type norsesquiterpenoids. In vitro bioactivity, 2a selectively inhibited Bcap-37 with IC50 value of 5.60 µM, and 9 selectively inhibited Du-145 with IC50 value of 5.52 µM. The anti-inflammatory activity of 1-9 were tested, and of these compounds, 1, 2a, 2b and 7 exhibited potent inhibitory effects.

Sesquiterpenoids from the roots of Lindera glauca and their cytotoxicity activities.

The chemical investigation of the roots of Lindera glauca guided the isolation and identification of 3 new sesquiterpenoids, namely glaucatotones J-L (1-3), and one known congener, (1ß,5ß)-1-hydroxyguaia-4(15),11(13)-dieno-12,5-lactone (4). The structures of new compounds were established based on comprehensive spectrographic methods, mainly including 1D & 2D NMR and HRESIMS analyses, and the absolute configurations were further confirmed by the comparison of experimental and calculated electronic circular dichroism. The cytotoxicity activities of isolates were evaluated, and the results showed that they have moderate cytotoxic activities.

Dihydropashanone Isolated from Lindera erythrocarpa, a Potential Natural Product for the Treatment of Neurodegenerative Diseases.

Lindera erythrocarpa, a flowering plant native to eastern Asia, has been reported to have neuroprotective activity. However, reports on the specific bioactive compounds in L. erythrocarpa are finite. The aim of this study was to investigate the anti-neuroinflammatory and neuroprotective effects of the compounds isolated from L. erythrocarpa. Dihydropashanone, a compound isolated from L. erythrocarpa extract, was found to have protected mouse hippocampus HT22 cells from glutamate-induced cell death. The antioxidant and anti-inflammatory properties of dihydropashanone in mouse microglial BV2 and HT22 cells were explored in this study. The results reveal that dihydropashanone inhibits lipopolysaccharide-induced inflammatory response and suppresses the activation of nuclear factor (NF)-κB in BV2 cells. In addition, dihydropashanone reduced the buildup of reactive oxygen species in HT22 cells and induced activation of the nuclear factor E2-related factor 2 (Nrf2)/heme oxygenase (HO)-1 signaling pathway in BV2 and HT22 cells. Our results suggest that dihydropashanone reduces neuroinflammation by decreasing NF-κB activation in microglia cells and protects neurons from oxidative stress via the activation of the Nrf2/HO-1 pathway. Thus, our data suggest that dihydropashanone offers a broad range of applications in the treatment of neurodegenerative illnesses.

[A new sesquiterpenoid from Lindera aggregata].

The chemical composition of the aqueous part of the extract from Lindera aggregata was studied, which was separated and purified by the macroporous resin column chromatography, MCI medium pressure column chromatography, semi-preparative high-performance liquid phase and other methods. The structures of the compounds were identified according to physical and chemical properties and spectroscopic data. Thirteen compounds were isolated and identified from the aqueous extracts, which were identified as(1S,3R,5R,6R,8S,10S)-epi-lindenanolide H(1), tachioside(2), lindenanolide H(3), leonuriside A(4), 3,4-dihydroxyphenyl ethyl ß-D-glucopyranoside(5), 3,4,5-trimethoxyphenol-1-O-6-α-L-rhamnose-(1→6)-O-ß-D-glucoside(6), 5-hydroxymethylfurfural(7),(+)-lyoniresin-4-yl-ß-D-glucopyranoside(8), lyoniside(9), norboldine(10), norisopordine(11), boldine(12), reticuline(13). Among them, compound 1 was a new one, and compounds 2, 5, 6, 8, 9 were obtained from L. aggregata for the first time. The inflammatory model was induced by lipopolysaccharide(LPS) in the RAW264.7 cells. The results showed that compounds 1, 8, 10 and 12 had significant anti-inflammatory activity.

Essential Oils of the Leaves of Epaltes australis Less. and Lindera myrrha (Lour.) Merr.: Chemical Composition, Antimicrobial, Anti-inflammatory, Tyrosinase Inhibitory, and Molecular Docking Studies.

Epaltes australis Less. has been traditionally used to treat fever and snake bites, whereas Lindera myrrha (Lour.) Merr. is well-known for addressing colds, chest pain, indigestion, and worm infestations. This study marks the first report on the chemical compositions and biological potentials of essential oils extracted from the leaves of Epaltes australis and Lindera myrrha. Essential oils obtained by hydro-distillation were analysed using the GC/MS (gas chromatography-mass spectrometry). E. australis exhibited a predominant presence of non-terpenic compounds (46.3 %), with thymohydroquinone dimethyl ether as the major compound, constituting 44.2 % of the oil. L. myrrha leaf oil contained a good proportion of sesquiterpene hydrocarbons (56.8 %), with principal compounds including (E)-caryophyllene (22.2 %), ledene (9.7 %), selina-1,3,7(11)-trien-8-one (9.6 %), and α-pinene (7.0 %). Both essential oils exhibited antimicrobial activity against the bacteria Bacillus subtilis and Clostridium sporogenes, and Escherichia coli, and the fungus Aspergillus brasiliensis. L. myrrha leaf essential oil exhibited potent control over the yeast Saccharomyces cerevisiae with a MIC of 32 µg/mL. Additionally, L. myrrha leaf oil showed strong anti-inflammatory activity with an IC50 value of 15.20 µg/mL by inhibiting NO (nitric oxide) production in LPS (lipopolysaccharide)-stimulated RAW2647 murine macrophage cells. Regarding anti-tyrosinase activity, E. australis leaf oil showed the best monophenolase inhibition with the IC50 of 245.59 µg/mL, while L. myrrha leaf oil successfully inhibited diphenolase with the IC50 of 152.88 µg/mL. From molecular docking study, selina-1,3,7(11)-trien-8-one showed the highest affinity for both COX-2 (cyclooxygenase-2) and TNF-α (tumor necrosis factor-α) receptors. Hydrophobic interactions play a great role in the bindings of ligand-receptor complexes.

Linderone Isolated from Lindera erythrocarpa Exerts Antioxidant and Anti-Neuroinflammatory Effects via NF-κB and Nrf2 Pathways in BV2 and HT22 Cells.

Linderone is a major compound in Lindera erythrocarpa and exhibits anti-inflammatory effects in BV2 cells. This study investigated the neuroprotective effects and mechanisms of linderone action in BV2 and HT22 cells. Linderone suppressed lipopolysaccharide (LPS)-induced inducible nitric oxide synthase, cyclooxygenase-2, and pro-inflammatory cytokines (e.g., tumor necrosis factor alpha, interleukin-6, and prostaglandin E-2) in BV2 cells. Linderone treatment also inhibited the LPS-induced activation of p65 nuclear factor-kappa B, protecting against oxidative stress in glutamate-stimulated HT22 cells. Furthermore, linderone activated the translocation of nuclear factor E2-related factor 2 and induces the expression of heme oxygenase-1. These findings provided a mechanistic explanation of the antioxidant and anti-neuroinflammatory effects of linderone. In conclusion, our study demonstrated the therapeutic potential of linderone in neuronal diseases.

[Chemical constituents of Lindera aggregata and their bioactivities: a review].

The medicinal Lindera aggregata(Lindera, Lauraceae) boasts abundant resources, which is widely used in clinical settings. It has been found that the main chemical constituents of this medicinal species are sesquiterpenoids, alkaloids, sesquiterpenoid dimers, flavonoids, and phenolic acids. Some unreported novel structures, including lindenane-type sesquiterpene dimers and trimers, have been discovered from L. aggregata in recent years. The extracts and active components of L. aggregata have anti-tumor, anti-inflammatory, antalgic, liver-protecting, antioxidant, lipid-lowering, and glucose-lowering activities, and their mechanisms of action have been comprehensively investigated. This study summarizes the research on the chemical constituents and bioactivities of L. aggregata over the past decade, which is expected to serve as a reference for the future research and utilization of L. aggregata.

Drug-drug interactions induced by Linderane based on mechanism-based inactivation of CYP2C9 and the molecular mechanisms.

Linderane (LDR) is a main furan-containing sesquiterpenoid of the common herbal medicine Lindera aggregata (Sims) Kosterm. Our early study indicated that LDR led to mechanism-based inactivation (MBI) of CYP2C9 in vitro, implying possible drug-drug interactions (DDIs) in clinic. In the present study, influence of LDR on the pharmacokinetics of the corresponding hydroxylated metabolites of CYP2C9 substrates in rats was investigated. Pharmacokinetic studies revealed that pretreatment with LDR at 20 mg/kg for 15 days inhibited the metabolism of both tolbutamide and warfarin catalyzed by CYP2C9. As for 4-hydroxytolbutamide, the Cmax was decreased, the t1/2z was prolonged, and the Vz/F was increased, all with significant difference. As for 7-hydroxywarfarin, the AUC0-t/AUC0-∞ and CLz/F were significantly decreased and increased, respectively. Furthermore, the underlying molecular mechanisms based on MBI of CYP2C9 by LDR were revealed. Two reactive metabolites of LDR, furanoepoxide and γ-ketoenal intermediates were identified in CYP2C9 recombinant enzyme incubation systems. Correspondingly, covalent modifications of lysine and cysteine residues of CYP2C9 protein were discovered in the CYP2C9 incubation system treated with LDR. The formation of protein adducts exhibited obvious time- and dose-dependence, which is consistent with the trend of enzyme inhibition caused by LDR in vitro. In addition to the apoprotein of CYP2C9, the heme content was significantly reduced after co-incubation with LDR. These data revealed that modification of both apoprotein and heme of CYP2C9 by reactive metabolites of LDR led to MBI of CYP2C9, therefore resulting in the inhibition of biotransformation of CYP2C9 substrates to their corresponding metabolites in vivo.

Effects of Compounds Isolated from Lindera erythrocarpa on Anti-Inflammatory and Anti-Neuroinflammatory Action in BV2 Microglia and RAW264.7 Macrophage.

Lindera erythrocarpa contains various constituents such as cyclopentenedione-, flavonoid-, and chalcone-type components. In this study, a novel bi-linderone derivative and 17 known compounds were isolated from the leaves of L. erythrocarpa by using various chromatographic methods. The structures of the components were determined from nuclear magnetic resonance and mass spectrometry data. All isolated compounds were tested for anti-inflammatory and anti-neuroinflammatory activities in lipopolysaccharide (LPS)-induced BV2 and RAW264.7 cells. Some of these compounds showed anti-inflammatory effects by inhibiting the nitric oxide (NO) produced by LPS. In particular, linderaspirone A (16), bi-linderone (17) and novel compound demethoxy-bi-linderone (18) showed significant inhibitory effects on the production of prostaglandin E2 (PGE2), tumor necrosis factor-α, and interleukin-6. The three compounds also inhibited the expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2), which are pro-inflammatory proteins, and the activation of nuclear factor κB (NF-κB). Therefore, linderaspirone A (16), bi-linderone (17), and demethoxy-bi-linderone (18) isolated from the leaves of L. erythrocarpa have therapeutic potential in neuroinflammatory diseases.

[Mechanism of Linderae Radix against gastric cancer based on network pharmacology and in vitro experimental validation].

The present study explored the main active ingredients and the underlying mechanism of Linderae Radix the treatment of gastric cancer by network pharmacology, molecular docking, and in vitro cell experiments. TCMSP, OMIM and GeneCards database were used to obtain the active ingredients of Linderae Radix to predict the related targets of both Linderae Radix and gastric cancer. After screening the common potential action targets, the STRING database was used to construct the PPI network for protein interaction of the two common targets. Enrichment analysis of GO and KEGG by DAVID database. Based on STRING and DAVID platform data, Cytoscape software was used to construct an "active ingredient-target" network and an "active ingredient-target-pathway" network. Molecular docking was performed using the AutoDock Vina to predict the binding of the active components to the key action targets, and finally the key targets and pathways were verified in vitro. According to the prediction results, there were 9 active components, 179 related targets of Radix Linderae, 107 common targets of Linderae Radix and gastric cancer, 693 biological processes, 57 cell compositions, and 129 molecular functions involved in the targets, and 161 signaling pathways involved in tumor antigen p53, hypoxia-indu-cible factor 1, etc. Molecular docking results showed that the core component, jimadone, had high binding activity with TP53. Finally, in an in vitro experiment, the screened radix linderae active ingredient gemmadone is used for preliminarily verifying the core targets and pathways of the human gastric cancer cell SGC-7901, The results showed that germacrone could significantly inhibit the proliferation of gastric cancer cells and induce the apoptosis of SGC-7901 by regulating the expression of p53, Bax, Bcl-2 and other key proteins. In summary, Radix Linderae can control the occurrence and development of gastric cancer through multi-components, multi-targets and multi-pathways, which will provide theoretical basis for further clinical discussion on the mechanism of Radix Linderae in treating gastric cancer.

Linderapyrone: A Wnt signal inhibitor isolated from Lindera umbellata.

Linderapyrone, a Wnt signal inhibitor was isolated from the methanolic extract of the stems and twigs of Lindera umbellata together with epi-(-)-linderol A. Linderapyrone inhibited TCF/ß-catenin transcriptional activity that was evaluated using cell-based TOPFlash luciferase assay system. To evaluate the structure-activity relationship and mechanism, we synthesized linderapyrone and its derivatives from piperitone. As the results of further bioassay for synthesized compounds, we found both of pyrone and monoterpene moieties were necessary for inhibitory effect. cDNA microarray analysis in a linderapyrone derivative treated human colorectal cancer cells showed that this compound downregulates Wnt signaling pathway. Moreover, we successes to synthesize the derivative of linderapyrone that has stronger inhibitory effect than linderapyrone and ICG-001 (positive control).

Butyrolactone and sesquiterpene derivatives as inhibitors of iNOS from the roots of Lindera glauca.

Nine previously undescribed butyrolactone and sesquiterpene derivatives, named cyclopentanone A (1), subamolides F and G (2 and 3), secosubamolide F (4), rupestonic acids J - L (5-7), linderaguaianols A and B (8 and 9), together with six known ones 10-15 were isolated from the roots of Lindera glauca. Their structures, including their absolute configurations were elucidated by extensive spectroscopic analysis, quantum chemical calculations, and Mo2(AcO)4-induced circular dichroism. Compound 1 that possessed a unique five-membered cyclopentane skeleton with a side chain was rarely found from natural sources. The biogenetic pathway for 1-4 was postulated. Secosubamolide F (4) inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW264.7 cells with IC50 value of 1.73 ± 0.18 µM and also significantly suppressed the production of iNOS. The binding interactions between 4 and iNOS were investigated using docking analyses.

Bioassay-Guided Isolation of Two Eudesmane Sesquiterpenes from Lindera strychnifolia Using Centrifugal Partition Chromatography.

In this study, a centrifugal partition chromatography (CPC) separation was applied to identify antioxidant-responsive element (ARE) induction molecules from the crude extract of Lindera strychnifolia roots. CPC was operated with a two-phase solvent system composed of n-hexane-methanol-water (10:8.5:1.5, v/v/v) in dual mode (descending to ascending), which provided a high recovery rate (>95.5%) with high resolution. Then, ARE induction activity of obtained CPC fractions was examined in ARE-transfected HepG2 cells according to the weight ratios of the obtained fractions. The fraction exhibiting ARE-inducing activity was further purified by preparative HPLC that led to isolation of two eudesmane type sesquiterpenes as active compounds. The chemical structures were elucidated as linderolide U (1) and a new sesquiterpene named as linderolide V (2) by spectroscopic data. Further bioactivity test demonstrated that compounds 1 and 2 enhanced ARE activity by 22.4-fold and 7.6-fold, respectively, at 100 µM concentration while 5 µM of sulforaphane induced ARE activity 24.8-fold compared to the control.

Subjective Effects of Inhaling Kuromoji Tea Aroma.

Teas and various herbal teas are well-known beverages and are commonly consumed around the world. In this study, we focused on kuromoji tea. Kuromoji is a deciduous shrub of the Lauraceae family, and the plucked leaves and branches have been drunk as a tea in production areas for a long time. However, no studies have investigated the subjective and physiological effects of kuromoji tea. In this study, the effects of kuromoji tea were examined on the basis of the measurements of heart rate variability and cerebral blood flow, core body temperature and subjective assessments. Moreover, the results of this study showed that a pleasant subjective feeling could be obtained by sniffing the aroma of kuromoji teas, especially tea leaves. It was also found that the aroma of kuromoji teas has the potential to stimulate saliva secretion and increase subjective and physiological excitements in the oral cavity. 1,8-Cineole, linalool, terpinen-4-ol, carvone and geraniol were determined in both kuromoji leaves and branches. In this study, the beneficial effects of kuromoji teas when drunk conventionally were investigated.

Psychological and Antibacterial Effects of Footbath Using the Lindera umbellata Essential Oil.

Lindera umbellata (Lu) essential oil primarily contains linalool and has relaxation properties. We investigated the psychological and antibacterial effects of footbath with Lu essential oil. The participants included 20 women without medical history and received two intervention plans: footbath without any essential oil and footbath using Lu essential oil. Next, questionnaires regarding impressions and mood states were provided for them to answer. In addition, their autonomic nervous system activity was measured, and the aerobic viable of count on the feet was determined. The high-frequency value reflecting the parasympathetic nervous system activity significantly increased after footbath using Lu essential oil. In the questionnaire about the mood states, the subscale scores of tension-anxiety, depression, fatigue, and confusion after intervention were lower than those before intervention regardless of the use of the essential oil. Conversely, the anger-hostility score decreased only in the group using Lu essential oil. Furthermore, the decrease in aerobic viable count after intervention was not significantly different between the two groups. Footbath using Lu essential oil increased the parasympathetic nervous system activity and relieved anger. Taken together, we suggest that footbath using Lu essential oil has a relaxation effect.

Mitigating Effect of Lindera obtusiloba Blume Extract on Neuroinflammation in Microglial Cells and Scopolamine-Induced Amnesia in Mice.

Lindera obtusiloba Blume (family, Lauraceae), native to Northeast Asia, has been used traditionally in the treatment of trauma and neuralgia. In this study, we investigated the neuroinflammatory effect of methanol extract of L. obtusiloba stem (LOS-ME) in a scopolamine-induced amnesia model and lipopolysaccharide (LPS)-stimulated BV2 microglia cells. LOS-ME downregulated the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, inflammatory cytokines, and inhibited the phosphorylation of nuclear factor kappa-B (NF-ĸB) and extracellular signal-regulated kinase (ERK) in LPS-stimulated BV2 cells. Male C57/BL6 mice were orally administered 20 and 200 mg/kg of LOS-ME for one week, and 2 mg/kg of scopolamine was administered intraperitoneally on the 8th day. In vivo behavioral experiments (Y-maze and Morris water maze test) confirmed that LOS-ME alleviated cognitive impairments induced by scopolamine and the amount of iNOS expression decreased in the hippocampus of the mouse brain. Microglial hyper-activation was also reduced by LOS-ME pretreatment. These findings suggest that LOS-ME might have potential in the treatment for cognitive improvement by regulating neuroinflammation.

Anti-inflammatory principles from Lindera aggregata.

Four new sesquiterpenes (1-4), one new alkaloid (5), and one new benzenoid glycoside (6) were characterized from Lindera aggregata, and their structures were elucidated according to their spectrometric analytical data. Among these isolates, 3 and 4 were constructed as possessing unprecedented carbon skeletons from the natural source. Some of these purified constituents were examined for their anti-inflammatory bioactivity. Among the tested compounds, linderaggredin C (3), (+)-N-methyllaurotetanine, and (+)-isoboldine displayed the significant inhibition of superoxide anion generation in human neutrophils with IC50 values of 7.45 ± 0.74, 8.36 ± 0.11, and 5.81 ± 0.59 µM, respectively.

Aqueous extracts of Lindera aggregate (Sims) Kosterm leaves regulate serum/hepatic lipid and liver function in normal and hypercholesterolemic mice.

The leaves of Lindera aggregate (Sims) Kosterm. are traditionally used as healthy tea for the prevention and treatment of hyperlipidemia in Chinese. The aim of this study was to evaluate the antihyperlipidemic effects and potential mechanisms of the aqueous extracts from L. aggregate leaves (AqLA-L) on normal and hypercholesterolemic (HCL) mice. HCL mice were induced by high fat diet (HFD) and orally administrated with or without AqLA-L for ten days. The results showed that AqLA-L (0.3, 0.6, 1.2 g/kg) significantly reduced serum TG, ALT, but elevated fecal TG in normal mice. AqLA-L (0.3, 0.6, 1.2 g/kg) also remarkably lowered serum TC, TG, LDL, N-HDL, ALT, GLU, APOB, hepatic GLU and increased serum HDL, APOA-I, fecal TG levels in HCL mice. These results revealed that AqLA-L treatment regulated the disorders of the serum lipid and liver function, reduced hepatic GLU contents both in normal and HCL mice. The potential mechanisms for cholesterol-lowering effects of AqLA-L might be up-regulation of cholesterol 7-alpha-hydroxylase (CYP7A1) and ATP-binding cassette transporter A1 (ABCA1), as well as down-regulation of 3-hydroxy-3-methylglutaryl CoA reductase (HMGCR). The data indicated that AqLA-L has potential therapeutic value in treatment of hyperlipidemia with great application security.

Atypical Lindenane-Type Sesquiterpenes from Lindera myrrha.

Two new lindenane sesquiterpenes were obtained from the roots of Lindera myrrha. These compounds were structurally elucidated by HRMS data, extensive NMR analyses, and comparison between experimental and theoretical 13C-NMR data. Myrrhalindenane A is the first monomeric seco-d lindenane displaying a non-rearranged, cyclohexanic C-ring. Myrrhalindenane B is the second occurrence of an angular lindenane-sesquiterpene related to a C6-C7 lactonization.

Comparison of Chemical Composition between Kuromoji (Lindera umbellata) Essential Oil and Hydrosol and Determination of the Deodorizing Effect.

Kuromoji (Lindera umbellata) is a tree that grows throughout Japan. The components of kuromoji essential oil have antitumor and aromatherapy effects. However, the composition of the hydrosol, obtained as a by-product of the essential oil process, is unknown. Furthermore, it is unknown whether kuromoji essential oil has a deodorizing effect. Therefore, the purpose of the current study was to compare the chemical composition of kuromoji essential oil and hydrosol, as well as evaluate the deodorizing effect of the former. The chemical composition of samples was evaluated using gas chromatography-mass spectrometry (GC-MS). Additionally, the deodorizing effect of Kuromoji essential oil was investigated with the detector tube method using ammonia, hydrogen sulfide, methyl mercaptan, and isovaleric acid. Linalool was the most abundant component in both the essential oil and hydrosol; however, its proportion was higher in the hydrosol (57.5%) than in the essential oil (42.8%). The hydrosol contained fewer chemical components, but higher proportions of trans-geraniol and ethanol. Moreover, the essential oil eliminated 50% of ammonia and 97.6% or more of isovaleric acid. Interestingly, linalool was soluble in the hydrosol and did not irritate the skin. This suggests that the hydrosol may be an effective foot care product.