Glycoside constituents from Cayratia geniculata.

Using various chromatographic separations, six glycoside derivatives (1-6), including one new ent-labdane glucoside named cayratioside (1), were isolated from the methanol extract of Cayratia geniculata stems and leaves. Their structures were elucidated by detailed analysis of the 1D, 2D NMR, and HRESIQTOF mass spectra. The inhibitory effect of 1-6 on LPS-induced NO production in RAW264.7 cells was also evaluated. Among isolated compounds, 1 exhibited moderate activity with an IC50 value of 59.65 ± 1.85 µM.

Asterosaponins from the starfish Protoreaster nodosus.

Five asterosaponins (1-5), including one new compound named protonodososide (1), were isolated from the methanol extract of the starfish Protoreaster nodosus, after subjecting to various chromatographic separations. The structural elucidation was confirmed by careful analysis of the 1D, 2D NMR, and HR ESI QTOF mass spectra. The cytotoxicity of isolated compounds was evaluated on five human cancer cell lines including HepG2, KB, MCF7, LNCaP, and SK-Mel2.

Fusarium solani PQF9 Isolated from Podocarpus pilgeri Growing in Vietnam as a New Producer of Paclitaxel.

Endophytic fungi are known as an alternative promising source of anticancer drug, paclitaxel, however fungi inhabiting in medicinal plant Podocarpus pilgeri and their paclitaxel production have not been reported to date. In the present study, a total of 15 culturable fungi classified into 5 genera, were successfully recovered from P. pilgeri collected in Vietnam. Screening fungal dichloromethane extracts for anticancer activity revealed that only PQF9 extract displayed potent inhibitory effects on A549 and MCF7 cancer cell lines with IC50 values of 33.9 ± 2.3 µg/mL and 43.5 ± 1.7 µg/mL, respectively. Through PCR-based molecular screening, the isolate PQF9 was found to possess 3 key genes involved in paclitaxel biosynthesis. Importantly, high-performance liquid chromatography quantification showed that fungal isolate PQF9 was able to produce 18.2 µg/L paclitaxel. The paclitaxel-producing fungus was identified as Fusarium solani PQF9 based on morphological and molecular phylogenetic analysis. Intensive investigations by chromatographic methods and spectroscopic analyses confirmed the presence of paclitaxel along with tyrosol and uracil. The pure paclitaxel had an IC50 value of 80.8 ± 9.4 and 67.9 ± 7.0 nM by using cell viability assay on A549 lung and MCF7 breast cancer cells. In addition, tyrosol exhibited strong antioxidant activity by scavenging 2, 2-diphenyl-picrylhydrazyl (DPPH) (IC50 5.1 ± 0.2 mM) and hydroxyl radical (IC50 3.6 ± 0.1 mM). In contrast, no biological activity was observed for uracil. Thus, the paclitaxel-producing fungus F. solani PQF9 could serve as a new material for large-scale production and deciphering paclitaxel biosynthesis. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-023-01119-z.

Sulfated Naphthopyrones and Anthraquinones from the Vietnamese Crinoid Comanthus delicata.

Three new sulfated naphthopyrone derivatives namely delicapyrons F-H (1-3) and two new sulfated anthraquinone derivatives namely delicaquinons A (4) and B (5), together with 6-methoxycomaparvin-5-methylether-8-O-sodium sulfate (6), 6-methoxycomaparvin-8-O-sodium sulfate (7), comaparvin-8-O-sodium sulfate (8), and 3-propyl-1,6,8-trihydroxy-9,10-anthraquinone-6-O-sodium sulfate (9) were isolated from the Vietnamese crinoid Comanthus delicata. Their chemical structures were elucidated by extensive analysis of the one dimensional (1D) and 2D-NMR, high resolution electrospray ionization quadrupole time-of-flight (HR-ESI-QTOF) mass spectra as well as calculation of optical rotation. In addition, significant cytotoxicity was observed for 6 against LNCaP (prostate cancer) cell line with IC50 value of 20.29 ± 2.43 µM, whereas moderate or weak cytotoxic effects were observed for 1-3 and 5-8 on SK-Mel-2 (melanoma) cell line and 7 and 8 against LNCaP cell line, with IC50 values ranging from 49.96 ± 1.74 to 76.92 ± 5.85 µM.

Chemical Constituents from the Branches and Leaves of Alchornea trewioides.

Two new megastigmane glucosides namely trewiosides A (1) and B (2), along with 20α-hydroxypregn-4-en-3-one ß-D-glucopyranoside (3), sugeroside (4), and schizandriside (5) were isolated from the branches and leaves of Alchornea trewioides. The structure elucidation was confirmed by extensive analysis of the one and two dimensional (1 and 2D) NMR, electronic circular dichroism (ECD) as well as high resolution electrospray ionization quadrupole time-of-flight (HR-ESI-QTOF) mass spectra. Noteworthily, the isolation of compounds 1 and 2 represents the second finding of megastigmane derivatives with a methoxycarbonyl group at C-5 to date. In addition, compound 3 showed weak cytotoxicity against three human cancer cell lines as A549 (lung carcinoma), HepG2 (hepatocarcinoma), and MCF7 (breast carcinoma). Besides, compounds 2 and 3 exhibited moderate inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 cells. Whereas, the remaining compounds 1, 4 and 5 showed weak inhibitory activity.

Diterpenoids and Flavonoids from Andrographis paniculata.

Chemical investigation of the aerial parts of Andrographis paniculata resulted in isolation of nine compounds, including a new ent-labdane diterpenoid, andrographic acid methyl ester (1), a new chalcone glucoside, pashanone glucoside (5), and seven known metabolites, andrograpanin (2), andrographolide (3), andropanolide (4), andrographidine A (6), andrographidine F (7), 6-epi-8-O-acetyl-harpagide (8), and curvifloruside F (9). Their chemical structures were elucidated based on comprehensive analyses of the spectroscopic data, including NMR and MS. Among the isolated compounds, andropanolide exerted cytotoxicity toward LNCaP, HepG2, KB, MCF7, and SK-Mel2 carcinoma cells, with IC50 values ranging from 31.8 to 45.9 µM. In addition, andropanolide significantly inhibited the overproduction of nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages, with an IC50 value of 13.4 µM.

Anti-inflammatory effect of 3,7-dimethyl-1,8-hydroxy-6-methoxyisochroman via nuclear factor erythroid 2-like 2-mediated heme oxygenase-1 expression in lipopolysaccharide-stimulated RAW264.7 and BV2 cells.

Objective: The isochroman-type fungal metabolite 3,7-dimethyl-1,8-hydroxy-6-methoxyisochroman (DMHM) was isolated from the extracts of a marine-derived fungal strain of Penicillium sp. SF-6013. In this study, we investigated the effect of DMHM on inflammatory response. Materials and methods: Anti-inflammatory effects of DMHM were examined in lipopolysaccharide (LPS)-stimulated RAW264.7 and BV2 cells. We observed their anti-inflammatory effects by ELISA, qRT-PCR, and western blot analysis. Results: DMHM revealed that it suppressed the production of prostaglandin E2 (PGE2), nitric oxide (NO), cyclooxygenase-2 (COX-2), and inducible NO synthase (iNOS) in LPS-stimulated RAW264.7 and BV2 cells. Furthermore, DMHM decreased the mRNA expression of pro-inflammatory cytokines including interleukin (IL)-1ß and IL-6. Therefore, DMHM was further investigated to elucidate the mechanisms of its anti-inflammatory properties; the results indicated that its effect was mediated by the suppression of the nuclear factor (NF)-κB and c-Jun N-terminal kinase (JNK) MAPK pathways. Furthermore, the anti-inflammatory activity of DMHM correlated with its induction of heme oxygenase-1 (HO)-1 expression via activation of the nuclear factor erythroid 2-like 2 (Nrf2) pathway. Discussion and conclusions: Collectively, the results of this study suggest that DMHM inhibited several inflammatory pathways including the NF-κB and MAPK pathways, and induced Nrf2-mediated HO-1 expression, demonstrating its potential usefulness for treating inflammatory and neuroinflammatory diseases.

Correction: Kim, D.-C.; et al. Steppogenin Isolated from Cudrania tricuspidata Shows Antineuroinflammatory Effects via NF-κB and MAPK Pathways in LPS-Stimulated BV2 and Primary Rat Microglial Cells. Molecules 2017, 22, 2130.

The author wishes to make the following correction to this paper [1].[...].

Anti-neuroinflammatory effects of cudraflavanone A isolated from the chloroform fraction of Cudrania tricuspidata root bark.

CONTEXT: Cudrania tricuspidata Bureau (Moraceae) is an important source of traditional Korean and Chinese medicines used to treat neuritis and inflammation. OBJECTIVE: The anti-neuroinflammatory effects of cudraflavanone A isolated from a chloroform fraction of C. tricuspidata were investigated in LPS-induced BV2 cells. MATERIALS AND METHODS: Cudraflavanone A was isolated from the root of C. tricuspidata, and its structure was determined by MS and NMR data. Cytotoxicity of the compound was examined by MTT assay, indicating no cytotoxicity at 5-40 µM of cudraflavanone A. NO concentration was measured by the Griess reaction, and the levels of PGE2, cytokines and COX-2 enzyme activity were measured by each ELISA kit. The mRNA levels of cytokines were analysed by quantitative-PCR. The expression of iNOS, COX-2, HO-1, NF-κB, MAPKs and Nrf2 was detected by Western blot. RESULTS: Cudraflavanone A had no major effect on cell viability at 40 µM indicating 91.5% viability. It reduced the production of NO (IC50 = 22.2 µM), PGE2 (IC50 = 20.6 µM), IL-1ß (IC50 = 24.7 µM) and TNF-α (IC50 = 33.0 µM) in LPS-stimulated BV2 cells. It also suppressed iNOS protein, IL-1ß and TNF-α mRNA expression. These effects were associated with the inactivation of NF-κB, JNK and p38 MAPK pathways. This compound mediated its anti-neuroinflammatory effects by inducing HO-1 protein expression via increased nuclear translocation of Nrf2. DISCUSSION AND CONCLUSIONS: The present study suggests a potent effect of cudraflavanone A to prevent neuroinflammatory diseases. Further investigation is necessary to elucidate specific molecular mechanism of cudraflavanone A.

Sesquiterpene derivatives from marine sponge Smenospongia cerebriformis and their anti-inflammatory activity.

Using various chromatographic methods, five new sesquiterpene derivatives named smenohaimiens A-E (1-5) and five known, 19-hydroxy-polyfibrospongol B (6), ilimaquinone (7), dictyoceratin C (8), polyfibrospongol A (9), and polyfibrospongol B (10) were isolated from the marine sponge Smenospongia cerebriformis Duchassaing & Michelotti, 1864. Their structures were assigned by 1D, 2D NMR spectroscopic analysis, HR ESI MS, and calculations of the electron circular dichroism spectra. All compounds were evaluated for the inhibitory activity against NO production in lipopolysaccharide-stimulated in BV2 microglia cells. As the results, compound 7 significantly inhibited NO production with the IC50 value of 10.40±1.28µM. The remaining compounds showed moderate inhibitory NO production activities with IC50 values ranging from 24.37 to 30.43µM.

Naphtoquinones and Sesquiterpene Cyclopentenones from the Sponge Smenospongia cerebriformis with Their Cytotoxic Activity.

Two new naphtoquinones (smenocerones A and B, 1 and 2) and four known sesquiterpene cyclopentenones (dactylospongenones A-D, 3-6) were isolated from sponge Smenospongia cerebriformis living in the Eastern Sea of Vietnam. Their chemical structures were determined by high resolution electrospray ionization (HR-ESI)-MS, NMR spectroscopic analysis, and in comparison with the reported data. The chiroptical properties of compounds 3-6 were examined by experiment and theoretical calculation of circular dichroism (CD) spectra to prove their absolute configurations. Compound 2 significantly exhibited cytotoxic activity towards lung carcinoma (LU-1), hepatocellular carcinoma (HepG-2), promyelocytic leukemia (HL-60), breast carcinoma (MCF-7), and melanoma (SK-Mel-2) human cancer cells with IC50 values of 5.5±0.8, 3.2±0.2, 4.0±0.7, 4.1±0.8, and 5.7±1.1 µg/mL, respectively.

Oleanane-type Saponins from Glochidion hirsutum and Their Cytotoxic Activities.

Five new oleanane-type saponins, hirsutosides A - E, were isolated from the leaves of Glochidion hirsutum (Roxb.) Voigt. Their structures were elucidated as 21ß-benzoyloxy-3ß,16ß,23,28-tetrahydroxyolean-12-ene 3-O-ß-d-glucopyranoside (1), 21ß-benzoyloxy-3ß,16ß,23,28-tetrahydroxyolean-12-ene 3-O-ß-d-glucopyranosyl-(1 â†’ 3)-ß-d-glucopyranoside (2), 21ß-benzoyloxy-3ß,16ß,23,28-tetrahydroxyolean-12-ene 3-O-6-acetyl-[ß-d-glucopyranosyl-(1 â†’ 3)]-ß-d-glucopyranoside (3), 21ß-benzoyloxy-3ß,16ß,23,28-tetrahydroxyolean-12-ene 3-O-ß-d-glucopyranosyl-(1 â†’ 3)-〈-l-arabinopyranoside (4), and 21ß-benzoyloxy-3ß,16ß,23-trihydroxyolean-12-ene-28-al 3-O-ß-d-glucopyranosyl-(1 â†’ 3)-α-l-arabinopyranoside (5). All isolated compounds were evaluated for cytotoxic activities on four human cancer cell lines, HepG-2, A-549, MCF-7, and SW-626 using the SRB assay. Compounds 1, 2, 4, and 5 showed significant cytotoxic activities against all human cancer cell lines with IC50 values ranging from 3.4 to 10.2 µm. Compound 3 containing acetyl group at glc C(6″) exhibited weak cytotoxic activity with IC50 values ranging from 47.0 to 54.4 µm.

Chemical Components from Phaeanthus vietnamensis and Their Inhibitory NO Production in BV2 Cells.

Phaeanthus vietnamensis Bân is a well-known medicinal plant which has been used for the treatment of various inflammatory diseases in traditional medicine. Using various chromatographic methods, three new compounds, (7S,8R,8'R)-9,9'-epoxy-3,5,3',5'-tetramethoxylignan-4,4',7-triol (1), 8α-hydroxyoplop-11(12)-en-14-one (5), and (1R,2S,4S)-4-acetyl-2-[(E)-(cinnamoyloxy)]-1-methylcyclohexan-1-ol (12) along with twelve known compounds were isolated from the leaves of P. vietnamensis. Their chemical structures were elucidated by physical and chemical methods. All compounds were evaluated for the inhibitory activities of nitric oxide production in LPS-stimulated BV2 cells. As the results, compound 6 showed the most potent inhibitory activity on LPS-stimulated NO production in BV2 cells with the IC50 values of 15.7 ± 1.2 µm. Compounds 2, 7, and 8 significantly inhibited inflammatory NO production with IC50 values ranging from 22.6 to 25.3 µm.

Steppogenin Isolated from Cudrania tricuspidata Shows Antineuroinflammatory Effects via NF-κB and MAPK Pathways in LPS-Stimulated BV2 and Primary Rat Microglial Cells.

Excessive microglial stimulation has been recognized in several neurodegenerative diseases, including Parkinson's disease (PD), Alzheimer's disease (AD), amyotropic lateral sclerosis (ALS), HIV-associated dementia (HAD), multiple sclerosis (MS), and stroke. When microglia are stimulated, they produce proinflammatory mediators and cytokines, including nitric oxide (NO) derived from inducible NO synthase (iNOS), prostaglandin E2 (PGE2) derived from cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-12 (IL-12), and interleukin-6 (IL-6). These inflammatory reactions are related to the nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Therefore, the modulation of NF-κB and MAPK is vital to prevent microglial activation and confer resistance against neuronal injury. In this study, steppogenin (1) isolated from Cudrania tricuspidata suppressed the neuroinflammatory responses to lipopolysaccharide (LPS). Steppogenin (1) inhibited the production of proinflammatory mediators and cytokines in LPS-challenged BV2 and rat primary microglial cells. Moreover, western blot analysis and immunofluorescence revealed that the nuclear translocation of NF-κB was inhibited in LPS-induced BV2 and rat primary microglial cells. The LPS-stimulated activation of BV2 and rat primary microglial cells was inhibited by steppogenin (1) through the suppression of c-Jun NH2-terminal kinase (JNK) and p38 MAPK signaling. These results suggested that steppogenin (1) exerted antineuroinflammatory effects against acute neuroinflammation in BV2 and rat primary microglial cells by suppressing the activation of NF-κB and MAPK signaling and the production of proinflammatory mediators and cytokines.

Spirostanol saponins from Tacca vietnamensis and their anti-inflammatory activity.

Using various chromatographic methods, five new steroidal saponins named taccavietnamosides A-E (1-5) and three known, (24S,25R)-spirost-5-en-3ß,24-diol 3-O-α-l-rhamnopyranosyl-(1→2)-[α-l-rhamnopyranosyl-(1→3)]-ß-d-glucopyranoside (6), (24S,25R)-spirost-5-en-3ß,24-diol 3-O-α-l-rhamnopyranosyl-(1→2)-[ß-d-glucopyranosyl-(1→4)-α-l-rhamnopyranosyl-(1→3)]-ß-d-glucopyranoside (7), and chantrieroside A (8) were isolated from the rhizomes of Tacca vietnamensis Thin et Hoat. Their chemical structures were elucidated by physical and chemical methods. All compounds were evaluated for the inhibitory activities of nitric oxide production in LPS-stimulated RAW 264.7 macrophages and BV2 cells. As the results, compounds 3-5 showed moderate inhibition on NO production in LPS-stimulated BV2 cells and RAW 264.7 macrophages with the IC50 values ranging from 37.0 to 60.7µM.

New Lignans from Antidesma hainanensis Inhibit NO Production in BV2 Microglial Cells.

Two new lignans (7S,7'R,8S,8'R)-3,3'-dimethoxy-7,7'-epoxylignan-4,4',9-triol 4-O-ß-D-glucopyranoside (1) and 9-O-formylaviculin (2) together with other thirteen known secondary metabolites were isolated from the leaves of Antidesma hainanensis. Their chemical structures were determined using NMR, electrospray ionization (ESI)-MS, circular dichroism (CD) spectroscopic methods, and as well as by comparison with those reported in the literature. Neuro-inflammatory activity of isolated compounds was evaluated by their inhibition on nitric oxide (NO) production in activated BV2 microglial cells. At concentration of 40 µM, compounds 1-3, 5, 7, 8, 9, 14, and 15 exhibited inhibitory effects over 50%, suggesting that they could be potential candidate drugs for the cure of neuro-inflammation. In addition, compounds 1, 8, 14, and 15 significantly inhibited 16.23, 27.76, 21.23, and 29.44% NO production at diluted concentration as low as 2.5 µM.

Prenylated Flavonoids from Cudrania tricuspidata Suppress Lipopolysaccharide-Induced Neuroinflammatory Activities in BV2 Microglial Cells.

In Korea and China, Cudrania tricuspidata Bureau (Moraceae) is an important traditional medicinal plant used to treat lumbago, hemoptysis, and contusions. The C. tricuspidata methanol extract suppressed both production of NO and PGE2 in BV2 microglial cells. Cudraflavanone D (1), isolated from this extract, remarkably suppressed the protein expression of inducible NO synthase and cyclooxygenase-2, and decreased the levels of NO and PGE2 in BV2 microglial cells exposed to lipopolysaccharide. Cudraflavanone D (1) also decreased IL-6, TNF-α, IL-12, and IL-1ß production, blocked nuclear translocation of NF-κB heterodimers (p50 and p65) by interrupting the degradation and phosphorylation of inhibitor of IκB-α, and inhibited NF-κB binding. In addition, cudraflavanone D (1) suppressed the phosphorylation of c-Jun N-terminal kinase (JNK) and p38 MAPK pathways. This study indicated that cudraflavanone D (1) can be a potential drug candidate for the cure of neuroinflammation.

A Prenylated Xanthone, Cudratricusxanthone A, Isolated from Cudrania tricuspidata Inhibits Lipopolysaccharide-Induced Neuroinflammation through Inhibition of NF-κB and p38 MAPK Pathways in BV2 Microglia.

Cudrania tricuspidata Bureau (Moraceae) is an important source of traditional Korean and Chinese medicines used to treat neuritis and inflammation. Cudratricusxanthone A (1), a prenylated xanthone, isolated from C. tricuspidata, has a variety of biological and therapeutic activities. The goal of this study was to examine the effects of compound 1 on neuroinflammation and characterize its mechanism of action in lipopolysaccharide (LPS)-stimulated BV2 microglia. Cudratricusxanthone A (1) suppressed the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 enzymes and decreased the production of iNOS-derived nitric oxide and COX-2-derived prostaglandin E2 in LPS-stimulated mouse BV2 microglia. The compound also decreased tumor necrosis factor-α, interleukin (IL)-1ß, and IL-12 production; inhibited the phosphorylation and degradation of IκB-α; and blocked the nuclear translocation of p50 and p65 in mouse BV2 microglia induced by LPS. Cudratricusxanthone A (1) had inhibitory effects on nuclear factor kappa B DNA-binding activity. Additionally, it inhibited the p38 mitogen-activated protein kinase signaling pathway. Our data suggests that cudratricusxanthone A (1) may be a useful therapeutic agent in the treatment of neurodegenerative diseases caused by neuroinflammation.

New ent-kauranes from the fruits of Annona glabra and their inhibitory nitric oxide production in LPS-stimulated RAW264.7 macrophages.

Three new ent-kaurane diterpenoids, 7ß,16α,17-trihydroxy-ent-kauran-19-oic acid (1), 7ß,17-dihydroxy-16α-ent-kauran-19-oic acid 19-O-ß-d-glucopyranoside ester (2), 7ß,17-dihydroxy-ent-kaur-15-en-19-oic acid 19-O-ß-d-glucopyranoside ester (3) along with five known compounds, paniculoside IV (4), 16α,17-dihydroxy-ent-kaurane (5), 16ß,17-dihydroxy-ent-kaurane (6), 16ß,17-dihydroxy-ent-kauran-19-al (7), and 16ß,17-dihydroxy-ent-kauran-19-oic acid (8) were isolated from the fruits of Annona glabra. Their chemical structures were elucidated by physical and chemical methods. All compounds were evaluated for inhibitory activity against nitric oxide (NO) production in LPS-stimulated RAW 264.7 macrophages. As the results, compound 3 showed potent inhibitory LPS-stimulated NO production in RAW 264.7 macrophages with the IC50 value of 0.01±0.01µM; compounds 1 and 7 showed significant inhibitory NO production with the IC50 values of 0.39±0.12µM and 0.32±0.04µM, respectively.

Dihydroisocoumarin Derivatives from Marine-Derived Fungal Isolates and Their Anti-inflammatory Effects in Lipopolysaccharide-Induced BV2 Microglia.

Chemical investigation of the EtOAc extracts of marine-derived fungal isolates Aspergillus sp. SF-5974 and Aspergillus sp. SF-5976 yielded a new dihydroisocoumarin derivative (1) and 12 known metabolites. The structures of the isolated metabolites were established by extensive spectroscopic analyses, including 1D and 2D NMR spectra and MS data. Among the metabolites, the absolute configuration of 5'-hydroxyasperentin (6) was determined by single-crystal X-ray diffraction analysis. The in vitro antineuroinflammatory effects of the metabolites were also evaluated in lipopolysaccharide (LPS)-stimulated microglial cells. Among the isolated metabolites, dihydroisocoumarin derivatives 1-6 (10-80 µM) were shown to inhibit LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production by suppressing the expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2), respectively, in LPS-stimulated BV2 microglia. Further, 1 (20-80 µM) was found to suppress the phosphorylation of the inhibitor of nuclear factor kappa B-α (IκB-α), interrupt the nuclear translocation of nuclear factor kappa B (NF-κB), and decrease the activation of p38 mitogen-activated protein kinase (MAPK).