Study on the Material Basis of Neuroprotection of Myrica rubra Bark.

Background: Increasing attention has been given to the search for neuroprotective ingredients from natural plants. Myrica rubra bark (MRB) has been used in traditional oriental medicine for over thousand years and has potential neuroprotection. Methods and Results: Ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was used to identify the compounds in MRB extract, and the MTT assay was performed to evaluate the neuroprotection of six major compounds from MRB against glutamate-induced damage in PC12 cells. The result displayed nineteen compounds were identified, and myricitrin and myricanol 11-sulfate were shown to have neuroprotection, which prevented cell apoptosis through alleviating oxidative stress by reducing the levels of reactive oxygen species and methane dicarboxylic aldehyde, as well as by enhancing the activities of superoxide dismutase. Conclusions: Several active compounds from MRB may offer neuroprotection and have the potential for the development of new drugs against central nervous system diseases.

Improved dialysis removal of protein-bound uremic toxins by salvianolic acids.

BACKGROUND: Indoxyl sulfate (IS) and p-cresyl sulfate (pCS) are two key protein-bound uremic toxins that accumulate in patients with end-stage renal disease. IS and pCS cannot be efficiently removed by conventional hemodialysis because they are highly bound to proteins. One promising means to optimize the removal of protein-bound uremic toxins involves using binding competitors to liberate uremic toxins from protein-binding partners. PURPOSE: In this study, we try to identify potential binding competitors that can enhance the dialysis removal of IS and pCS in natural compounds of phytomedicine. METHODS: We employed microdialysis to evaluate whether Danhong injection (DHI) and its salvianolic acids can increase the free fractions of IS and pCS and thus improve their dialysis efficiency in vitro. Furthermore, we confirmed the positive effects of DHI and salvianolic acids in vivo on chronic kidney disease model rats in which IS and pCS had heavily accumulated. RESULTS: DHI significantly increased the dialysis efficiency of IS and pCS by 99.13% and 142.00% in vitro (10-fold dilution), respectively, and by 135.61% and 272.13% in vivo (4.16 ml/kg). Salvianolic acids including lithospermic acid (LA), salvianolic acid A (SaA), tanshinol (DSS), caffeic acid (CA), salvianolic acid B (SaB), protocatechuic aldehyde (PA) and rosmarinic acid (RA) significantly enhanced the dialysis removal of IS and pCS in a concentration-dependent manner. LA, the best competitor of the tested salvianolic acids, increased dialysis efficiency levels of IS and pCS by 197.23% and 198.31% in vitro (400 µM), respectively, and by 119.55% and 127.56% in vivo (24.69 mg/kg). CONCLUSION: The removal of protein-bound uremic toxins IS and pCS using DHI or salvianolic acids as protein-bound competitors is superior to previously reported strategies and drugs and may contribute to clinical hemodialysis therapeutic practice.

Dereplication and targeted isolation of bioactive sulphur compound from bacteria isolated from a hydrothermal field.

Marine micro-organisms in the deep-sea hydrothermal vent systems are considered as potential sources of bioactive natural products. Sixteen bacterial strains were isolated from a deep-sea hydrothermal field and screened for bioactive metabolism studies. After the strains were subjected to bioactive testing at different culture media, chemical dereplication by HPLC coupled to high-resolution mass spectrometer was performed to analyse or determine the main secondary metabolisms in those strains. Strain 06204 was large-scale fermented with relative optimal media, for isolating the desired sulphur compound. Butyrolactone I 3-sulphate was isolated and structurally identified from the extract, guided by dereplication and showed moderate antivirus activities against H3N2 and EV71 viruses. Our study suggests that deep-sea hydrothermal bacteria are good sources of sulphur natural products. Meanwhile, the described approach, mainly bioactive screening, dereplication and targeted isolation, is effective and efficient to discover interesting bioactive compounds in hydrothermal bacteria.

Anti-inflammatory activity of sulfate-containing phenolic compounds isolated from the leaves of Myrica rubra.

Three sulfated phenolic compounds, juglanin B (11R)-O-sulfate (1), myricetin 3´-O-sulfate (2), and ampelopsin 3´-O-sulfate (3), were isolated from the leaves of Myrica rubra. Compound 1 was a new sulfated lignan, 2 was a new sulfated flavone, and 3 was a known sulfated flavone. The structures of the new compounds (1 and 2) were determined by acid hydrolysis and spectroscopic methods, including IR, FAB-MS, 1D and 2D NMR. The inhibitory activities of compounds 1-3 and their hydrolysates (1a-3a) against LPS-induced cytokine (TNF-α, IL-1ß, and IL-6) production in macrophage RAW 264.7 cells were evaluated. The 2 new compounds (1 and 2) and their aglycones (1a and 2a) significantly reduced LPS-induced expression of iNOS and COX-2 proteins.

Three new triterpene glycosides from Ilex asprella.

Three new sulfated triterpene glycosides, asprellanosides C-E (1-3), were isolated from the roots of Ilex asprella. Their structures were elucidated as 3ß-[(2-O-sulfo-ß-d-xylopyranosyl)oxy]urs-12,19(29)-diene-28-oic acid 28-ß-d-glucopyranoside (1), 3ß-[(2-O-sulfo-ß-d-xylopyranosyl)oxy]urs-12,19-diene-28-oic acid 28-ß-d-glucopyranoside (2), and 3ß-[(2-O-sulfo-ß-d-xylopyranosyl)oxy]urs-12,19-diene-28-oic acid (3) on the basis of the spectral and chemical methods.

A novel sterol sulfate and new oligosaccharide polyester from the aerial parts of Polygala sibirica.

Polygalasterol A (1), a new sterol sulfate, and a new oligosaccharide ester, polygalasibiricose I (2), have been isolated from the n-butanol soluble fraction of the aerial parts of Polygala sibirica L. Their structures were determined to be (24R)-24-sulfo-5a-cholestane-3a,7a,12a,24-tetrol (1) and 3-O-benzoyl-beta-D-fructofuranosyl-(2-->1 )-[beta-D-glucopyranosyl-( 1 --2)]-4-0- {4-0-[3-O-[3-O-benzoyl-(2-O-acetyl)-alpha-L-rhamnopyranosyl-(1-->3 )]-2-O-acetyl-alpha-L-rhamnopyranosyl]-(Z)-p-coumaroyl}-alpha-D-glucopyranoside (2), respectively, by HRESIMS, and 1D and 2D NMR spectroscopic studies.

Three new sulfated triterpenoids from the roots of Gypsophila pacifica.

Three new sulfated triterpenoids (1-3), along with one known compound (4), were isolated from the roots of Gypsophila pacifica Kom. The structures of the new compounds were established as 3ß-O-sulfate gypsogenin 28-O-ß-d-glucopyranosyl ester (1), 3ß-O-sulfate gypsogenin (2), and 3ß-O-sulfate quillaic acid (3) on the basis of 1D, 2D NMR, and HR-ESI-MS methods.

Two new glycosides from Breynia vitis-idaea.

A new sulfur-containing spiroketal glycoside, breynin I (1), and a new terpenic glycoside, breyniaionoside E (2), together with 10 known compounds, were isolated from the aerial parts of Breynia vitis-idaea (Euphorbiaceae), a traditional Chinese medicine used for the treatment of chronic bronchitis and wounds. Their structures were elucidated on the basis of spectroscopic analysis and modified Mosher's method.

Composition of the fresh leaves and stems of Melissa officinalis and evaluation of skin irritation in a reconstituted human epidermis model.

The composition of a centrifuged product obtained from the fresh leaves and stems of Melissa officinalis and skin irritation in the reconstituted human epidermis (Episkin model) have been investigated in comparison to the EtOH-H(2)O (1:1) extract obtained by Soxhlet from the dried plant. Two new sulfated triterpenes (1 and 2) and two ionol derivatives have been isolated for the first time from Melissa officinalis together with caffeic and rosmarinic acids. The structures of compounds 1 and 2 were established by analysis of their spectroscopic data. Both the centrifuged material and its major constituents neither affected cell viability nor caused the release of pro-inflammatory mediators or the decrease of trans-epithelial electrical resistance (TEER) in the reconstituted human epidermis.

Sulfated lupane triterpene derivatives and a flavone C-glycoside from Gypsophila repens.

A new sulfated lupane triterpene, Gypsophilin (1), and its glucosyl ester, Gypsophilinoside (2) were isolated from the roots of Gypsophila repens whereas a new flavone C-glycoside (3) was obtained from the aerial parts. Their structures were established as (3beta)-3-O-(sulfo)lup-20(29)-en-23,28-dioic acid (1), (3beta)-3-O-(sulfo)lup-20(29)-en-23,28-dioic acid -28-O-beta-D-glucopyranosyl ester (2) and luteolin-7-O-alpha-L-arabinopyranosyl-6-C-beta-glucopyranoside (3) by spectroscopic methods such as 1D and 2D NMR, HR-ESI-MS and FAB-MS.

Sulfated triterpene derivatives from Fagonia arabica.

Two new sulfated triterpenes (1, 6) and four new sulfated triterpene glycosides (2-5) have been isolated from the aerial parts of Fagonia arabica. Their structures were established by spectroscopic data analysis. Compounds 1/2 and 3/4 are sulfated derivatives of the rare sapogenins 3beta,27-dihydroxyolean-12-en-28-oic acid and 3beta,27-dihydroxyurs-12-en-28-oic acid, respectively. Compound 5 is an unusual disulfated oleanene derivative characterized by the occurrence of a 13,18-double bond, while compound 6 is the first reported naturally occurring saturated and sulfated pentacyclic triterpene of the taraxastane series with a C-20,28 lactone unit.

A new pterocarpan, (-)-maackiain sulfate, from the roots of Sophora subprostrata.

A new pterocarpan, (-)-maackiain 3-sulfate (1) was isolated from the methanol extract of roots of Sophora subprostarata together with (-)-maackiain (2), trifolirhizin (3), lupeol (4), ononin (5), 7,4'-dihydroxyflavone (6), and (+)-syringaresinol (7). The structure of 1 was determined by analyses of 2D NMR and HRFABMS. Compounds 5-7 were isolated from this plant for the first time.

Isolation of new alkylthiosulfides from the essential oil and extracts from the bark of Scorodophloeus zenkeri Harms.

2,3,5-trithiahexane, 2,3,4,6-tetrathiaheptane, 2,4,5,7-tetrathiaoctane, two pentathianonanes, 2,4,5,7,9-pentathiadecane and two hexathiaundecanes were isolated from the essential oil and extracts from the bark of Scorodophloeus zenkeri Harms. Four other thioalkanes were found in small amounts in the essential oil.