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Phytochemical investigation on the dried fruits of Casearia grewiifolia led to the identification of 10 new salicinoyl quinic acid derivatives (1-10), a new benzoyl quinic acid (11), and two known compounds (12 and 13). The structures of the new compounds were elucidated by interpreting 1D and 2D NMR spectroscopic data including HMBC and EXSIDE along with a chemical method for sugar unit analysis. All isolates were evaluated for their inhibitory activities against prostaglandin E2 (PGE2) production in ultraviolet B (UVB)-irradiated HaCat keratinocytes. Of the isolates tested, compounds 6 and 12 were found to inhibit PGE2 production with IC50 values of 20.5 and 28.8 μM, respectively.

Gaylussacin (1), a stilbene glucoside, has been isolated from Pentarhizidium orientale and is used in Korean folk medicine. Although it was first isolated in 1972, the synthesis of gaylussacin has ...

Phytochemical investigation of the methanol extract of the aerial parts of Salvia plebeia aided by a proprotein convertase subtilisin/kexin type 9 (PCSK9) mRNA expression screening assay in HepG2 cells led to the identification of 19 compounds including one new norsesquiterpene (1), six new eudesmane sesquiterpenoids (2-5, 8, and 11), and 12 known compounds. The structures of all compounds were elucidated by interpretation of their 1D and 2D NMR spectroscopic and MS data. Furthermore, computational prediction of ECD or chemical shifts was used to propose the absolute configurations of the new structures. All isolates were assessed for their inhibitory activities against PCSK9 mRNA expression and PCSK9-low-density lipoprotein receptor (LDLR) interactions. None of the isolated compounds inhibited PCSK9 and LDLR interactions. However, compounds 1, 9, and 10 downregulated PCSK9 mRNA expression.

Three acylated saponins and three flavonoid glycosides, along with nine known flavonoids, were isolated from the fruits of Stewartia koreana Nakai ex Rehder (Theaceae) using relative mass defect filtering analysis. The structures of these compounds were determined by performing spectroscopic analyses and using chemical methods. Furthermore, all the isolates were evaluated for their effects on the mRNA expression of the genes for proprotein convertase subtilisin/kexin type 9 (PCSK9) and low-density lipoprotein receptor (LDLR) as well as their inhibitory activities on PCSK9 and LDLR binding. None of the isolates was deemed to be active in PCSK9-LDLR binding inhibition. However, (+)-catechin was found to inhibit PCSK9 expression and increase LDLR expression, suggesting the potential of (+)-catechin to lower cholesterol level via the downregulation of PCSK9 expression.

This study was aimed to evaluate the potential neurotrophic effect of Lycium barbarum fruit extract (LB-E) via increased neurite outgrowth and synaptic formation, and its neurotrophic and neuroprotective efficacy was also checked in vitro. LB-E exerted neurotrophic effects by regulating TrkA/ERK/CREB signaling. In nervous system, LB-E promoted neuronal survival and differentiation by increasing neurotrophic factor secretion in C6 glioma cells. Interestingly, LB-E increased the expressed levels of synaptophysin and GAP-43 in CNS cell lines. It also subsequently increased the number of ciliated cells and length of cilia in N1 hypothalamic neuronal cells induced by CNTF and displayed the enhanced dendrite length in primary cortical neurons. We investigated N-trans feruloyl tyramine (NTFT) from LB-E by LC-MS/MS, and confirmed NTFT as a biologically active ingredient showing the neurotrophic effect. These results suggested that NTFT from LB-E may be beneficial in the treatment of age-related brain diseases caused by the deficiency of neurotrophins.

In this study, the chemical diversity of polyphenols in Iris lactea var. chinensis seeds was identified by combined MS/MS-NMR analysis. Based on the annotated chemical profile, the isolation of stilbene oligomers was conducted, and consequently, stilbene oligomers (1-10) were characterized. Of these, compounds 1 and 2 are previously undescribed stilbene dimer glycoside (1) and tetramer glycoside (2), respectively. Besides, to evaluate this plant seed as a rich source of stilbene oligomers, we quantified three stilbene oligomers of I. lactea var. chinensis seeds. The contents of three major stilbene oligomers&mdash, trans-&epsilon, viniferin (3), vitisin A (6), and vitisin B (9)&mdash, in I. lactea var. chinensis seeds were quantified as 2.32 (3), 4.95 (6), and 1.64 (9) mg/g dry weight (DW). All the isolated compounds were tested for their inhibitory activities against influenza neuraminidase. Compound 10 was found to be active with the half maximal inhibitory concentration (IC50) values at 4.76 &mu, M. Taken together, it is concluded that I. lactea var. chinensis seed is a valuable source of stilbene oligomers with a human health benefit.

In recent years, investigations into the biochemistry of insect-associated bacteria have increased. When combined with analytical dereplication processes, these studies provide a powerful strategy to identify structurally and/or biologically novel compounds. Non-ribosomally synthesized cyclic peptides have a broad bioactivity spectrum with high medicinal potential. Here, we report the discovery of three new cyclic tripeptides: natalenamides A&ndash, C (compounds 1&ndash, 3). These compounds were identified from the culture broth of the fungus-growing termite-associated Actinomadura sp. RB99 using a liquid chromatography (LC)/ultraviolet (UV)/mass spectrometry (MS)-based dereplication method. Chemical structures of the new compounds (1&ndash, 3) were established by analysis of comprehensive spectroscopic methods, including one-dimensional (1H and 13C) and two-dimensional (1H-1H-COSY, HSQC, HMBC) nuclear magnetic resonance spectroscopy (NMR), together with high-resolution electrospray ionization mass spectrometry (HR-ESIMS) data. The absolute configurations of the new compounds were elucidated using Marfey&rsquo, s analysis. Through several bioactivity tests for the tripeptides, we found that compound 3 exhibited significant inhibitory effects on 3-isobutyl-1-methylxanthine (IBMX)-induced melanin production. The effect of compound 3 was similar to that of kojic acid, a compound extensively used as a cosmetic material with a skin-whitening effect.

Thirteen C-methylated flavonoid glycosides (1–13), along with 15 previously known flavonoids (14–28), were isolated from rhizomes of Pentarhizidium orientale. Among these compounds, matteuorienates D–K (1–8) were obtained as analogues of matteuorienates A–C (14–16), which contain a characteristic 3-hydroxy-3-methylglutaryl (HMG) moiety. The structures of 1–13 were characterized by spectroscopic analysis and chemical derivatization. The isolates were evaluated for their antiviral activities against influenza virus (H1N1), with compounds 21, 22, 23, 25, and 26 showing inhibitory effects (IC50 of 23.9–30.3 μM) against neuraminidases.

Background Nonalcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome. Recently, the inhibitory effects of flavone glycosides isolated from Sicyos angulatus extract on hepatic lipid accumulation in vitro were demonstrated. However, the effects of S. angulatus extract and its major flavonoid glycoside on in vivo hepatic steatosis induced by a high-fat diet have not yet been established. Hypothesis/Purpose The aim of this study was to investigate the effects of S. angulatus extract and its major flavonoid glycoside, kaempferol 3-O-[α- l -rhamnopyranosyl-(1→6)]-β- d -glucopyranosyl-7-O-α- l -rhamnopyranoside, on hepatic steatosis in high-fat diet-fed mice, which serves as a model of NAFLD. In addition, attempts have been made to chemically profile the metabolites involved in the activity of the S. angulatus extract. Methods C57BL/6 J mice were divided into vehicle, total extract of S. angulatus (SA; 50, 100 and 200 mg/kg) and major active component (20 mg/kg) groups. The mice were fed a high-fat diet (HFD) with or without S. angulatus extract or its major single compound for 10 weeks. Chemical identification was carried out using ultra-high-pressure liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UHPLC-qTOF-MS/MS) and then quantified by HPLC-DAD. Results Administration of S. angulatus extract significantly lowered plasma ALT and AST levels in HFD-fed mice compared to those of the vehicle group. The hepatic lipid content, as evidenced by oil-red O staining and quantification, was significantly lower in the S. angulatus-administered group, and the effect was dose dependent. These beneficial effects of S. angulatus extract were related to the decreased expression of hepatic genes involved in fatty acid (ACC1, FAS and SCD1) and triglyceride (DGAT) synthesis. The expression levels of two key transcription factors regulating lipogenesis, SREBP-1c and PPARγ, were significantly suppressed in the liver by administration of S. angulatus extract with HFD. Treatment of the HFD-fed mice with the major compound isolated from S. angulatus extract resulted in improved liver function along with an anti-steatotic effect similar to the results seen with S. angulatus extract. For the standardization of the S. angulatus extract, 23 compounds were identified based on MS/MS fragmentation and UV spectroscopy. Quantitative analysis of the major compound showed that the major component was present in 15.35 ± 0.01 mg/g of total extract. Conclusion These findings suggest that S. angulatus extract and its major component have the potential to improve liver function and hepatic steatosis in diet-induced obese mice.

Lignans are known to be an important class of phenylpropanoid secondary metabolites. In the course of our studies on the chemodiversity of lignans, the necessity arose to develop a method for the fast detection and identification of bioactive lignan subclasses. In this study, we detected 10 lignan derivatives of different extracts of F. viridissima by UHPLC-ESI-QTOF-MS. Lignan glycosides (1 and 2), lignans (3 and 4), and lignan dimers (5&ndash, 10) were identified by analysis of their exact masses and MSe spectra along with the characteristic mass fragmentation patterns and molecular formulas. We further investigated NO inhibitory effects of F. viridissima fractions and their major lignan derivatives to evaluate those anti-inflammatory effects. The methylene chloride fraction of F. viridissima as well as compounds 8 and 10 showed potent dose-dependent NO inhibitory effects on RAW 264.7 cells. Corresponding to the NO inhibition by compounds 8 and 10, lipopolysaccharide (LPS)-induced inducible nitric oxide synthase (iNOS) expression was notably reduced by both compounds. Our combined data with the bioactive results and the component analysis by UHPLC-ESI-QTOF-MS suggest that the methylene chloride fraction of F. viridissima roots could be potential anti-inflammatory agents and these are related to major lignans including dimeric dibenzylbutyrolactone lignans.

Ethnopharmacological relevance The fruits of Schisandra chinensis (Trucz.) Baill. (Schisandraceae) which have been used as a tonic especially for kidney yin deficiency in Chinese traditional medicine are recently receiving attention for its preventive activity on age-related neurodegenerative diseases. A variety of studies demonstrated the cognitive-enhancing effects of Schisandra chinensis through animal tests and also in clinical trials. Aim of study In this study, we attempted to investigate the effects of the lignan-riched extract of Schisandra chinensis fruits (ESP-806) on neurotoxicity and memory impairment induced by Aβ 1–42 injection in mice. Materials and methods The fruits of Schisandra chinensis were extracted with the mixture of n -hexane:ethanol (9:1), which is riched with bioactive dibenzocyclooctadiene lignans, schizandrin, gomisin N, wuweigisu C. After oral treatment of ESP-806 (100 mg/kg body weight) followed by injection of Aβ 1–42 (2 μg/mouse, i.c.v. ), novel object recognition and passive avoidance tests were evaluated. To verify the cognition enhancing effects of ESP-806, we examined the effects of ESP-806 on the activities of β -secretase and acetylcholinesterase, and the contents of Aβ and the reduced glutathione within the cortex and hippocampus of Aβ-injected mice. Results Oral treatment of ESP-806 (100 mg/kg body weight) significantly attenuated Aβ 1–42 -induced memory impairment evaluated by behavioral tests. Furthermore, the treatment of ESP-806 attenuated the elevation of β -secretase activity accompanying the reduced level of Aβ 1–42 in the cortex and hippocampus of the brain. ESP-806 also significantly inhibited the acetylcholinesterase activity in the hippocampus and increased the content of the reduced glutathione in the cortex and hippocampus of mouse brain. Conclusions These data suggested that the extract of Schisandra chinensis fruits riched with dibenzocyclooctadiene lignans may be useful in the prevention and treatment of Alzheimer's disease.

Diarylheptanoids have been the center of the intensive research efforts for Alzheimer's disease and other neurodegenerative diseases. The present study aimed to determine the effect of the standardized extract of B. platyphylla bark and its major diarylheptanoids in scopolamine-induced amnesic mice through cyclic AMP response element-binding protein (CREB) activation. Oral administration of the standardized extract of B. platyphylla bark (100 mg/kg body weight), aceroside VIII (1 mg/kg body weight) and platyphylloside (1 or 2 mg/kg body weight) significantly ameliorated scopolamine-induced amnesia in passive avoidance test. CREB phosphorylation and brain-derived neurotrophic factor (BDNF) expression in the cortex and hippocampus of the scopolamine-treated mice were markedly increased by the treatment of the standardized extract of B. platyphylla bark and platyphylloside. The standardized extract of B. platyphylla bark and its major diarylheptanoids also significantly protected HT22 cells against neurotoxicity induced by glutamate insult. The standardized extract of B. platyphylla bark and platyphylloside may ameliorate memory deficits by activating the CREB–BDNF pathway and prevent a neurodegeneration by inhibiting neuronal cell death.

Bioassay-guided fractionation of the EtOAc extract from Disporum viridescens roots led to the isolation of five new benzyl benzoate glycosides, BBGs (1-5). The neuroprotective activities of the BBGs were screened using neuronal HT22 hippocampal cells. BBG-D (4) significantly protected murine hippocampal HT22 cells against glutamate-induced neurotoxicity by maintaining the antioxidative defense systems such as superoxide dismutase, glutathione reductase, glutathione peroxidase, and the glutathione content. BBG-D, in a dose-and time-dependent manner, increased HO-1 expression through the selective activation of pERK signaling among the MAPK pathways. These results suggest that BBG-D could be a promising candidate for the treatment of neurodegenerative diseases related to glutamate-induced oxidative neuronal cytotoxicity.

The neuroprotective potential of flavonoids within the brain comprises anti-apoptosis of neuronal cells, anti-neuroinflammation and enhancement of cognitive function. We reported that Rhus vernciflua inhibits glutamate-induced neurotoxicity in primary cultured rat cortical cells. Here we narrowed it down to get neuroprotective fractions from the plant yielding flavonoid-rich ethyl acetate fraction (PREF). Among its active flavonoids, fisetin exhibited not only inhibitory effect against lipopolysaccharide (LPS)-induced neuroinflammation by suppressing inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 but also memory enhancing effects via reactivation of cAMP responsive element binding protein (CREB)-brain derived neurotrophic factor (BDNF) pathway in memory-impaired mice by scopolamine. Butein also showed a similar activity to fisetin even though to a lesser extent. The neuroprotection by PREF and selected flavonoids may involve maintenance of antioxidant defense mechanism including glutathione peroxidase (GSH-Px), glutathione reductase (GR) and superoxide dismutase (SOD). Conclusively, we demonstrate the R. vernciflua bark extract and its active flavonoids with potent neuroprotective and anti-inflammatory effects might be good therapeutic candidates as cognitive-enhancers.

A methanolic extract of the roots of Polygala tenuifolia (Polygalaceae) significantly attenuated nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated BV2 microglia cells. Five xanthones, 1-hydroxy-7-methoxyxanthone (1), 3,6-dihydroxy-1,2,7-trimethoxyxanthone (2), 1,3,6-trihydroxy-2,7-dimethoxyxanthone (3), 1,7-dihydroxy-2,3-dimethoxyxanthone (4) and 1,7-dihydroxy-3-methoxyxanthone (5), and five phenylpropanoids, 4-hydroxy-3-methoxypropiophenone (6), methyl 4-hydroxy-3-methoxycinnamic acid (7), 3,4,5-trimethoxycinnamic acid (8), 4-methoxycinnamic acid (9) and β-d-(3-O-sinapoyl) fructofuranosyl-α-d-(6-O-sinapoyl)glucopyranoside (10), were isolated from CHCl(3) fraction using bioactivity-guided fractionation. Among these compounds, compounds 1, 2, 4, 5 and 7 showed significant inhibitory effects on LPS-induced NO production in BV2 microglia cells at the concentration ranging from 10.0 to 100.0 μM.