Cerebrosides from Longan Arillus

Isolation of New Constituents from Whole Plant of Salsola imbricata Forssk. of Saudi Origin

This work describes the first report of the known glycosidic constituents β-sitosterol-3-O-β-d-glucoside-6'-palmitate (1), β-sitosterol-3-O-β-d-glucoside (2), momor-cerebroside I (3), phytolacca cerebroside (4), 1,2-di-O-palmitoyl-3-O-(6-sulfoquinovopyranosyl)-glycerol (5), isorhamnetin-3-robinobioside (6), and isorhamnetin-3-rutinoside (7) from the plant Salsola imbricata Forssk. grown in the eastern region of Saudi Arabia. The structures of the isolated compounds were elucidated from extensive 1D and 2D nuclear magnetic resonance (NMR), gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS), and chemical analyses. Compound 1 is reported for the first time from the Amaranthaceae family. In addition to the isolated and identified fatty alcohols, compounds 3, 4, 5, and 6 are also reported for the first time from the genus Salsola. The findings of this study suggest a contribution of the isolated compounds to the various biological activities reported for this plant.

Chemical Characterization and Metabolic Profiling of the Compounds in the Chinese Herbal Formula Li Chang Decoction by UPLC-QTOF/MS

Background

Li Chang decoction (LCD), a Chinese medicine formula, is commonly used to treat ulcerative colitis (UC) in clinics.

Purpose

This study aimed to identify the major components in LCD and its prototype and metabolic components in rat biological samples.

Methods

The chemical constituents in LCD were identified by establishing a reliable ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF/MS) method. Afterwards, the rats were orally administered with LCD, and the biological samples (plasma, urine, and feces) were collected for further analyzing the effective compounds in the treatment of UC.

Result

A total of 104 compounds were discriminated in LCD, including 26 flavonoids, 20 organic acids, 20 saponins, 8 amino acids, 5 oligosaccharides, 5 tannins, 3 lignans, 2 alkaloids, and 15 others (nucleosides, glycosides, esters, etc.). About 50 prototype and 94 metabolic components of LCD were identified in biological samples. In total, 29 prototype components and 22 metabolic types were detected in plasma. About 27 prototypes and 96 metabolites were discriminated in urine, and 34 prototypes and 18 metabolites were identified in feces.

Conclusion

The flavonoids, organic acids, and saponins were the major compounds of LCD, and this study promotes the further pharmacokinetic and pharmacological evaluation of LCD.

Longan (Dimocarpus longan Lour.) Aril ameliorates cognitive impairment in AD mice induced by combination of D-gal/AlCl3 and an irregular diet via RAS/MEK/ERK signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

According to the theory of traditional Chinese medicine (TCM), Alzheimer's disease (AD) is identified as "forgetfulness" or "dementia", and it can be caused by spleen deficiency. Longan Aril (the aril of Dimocarpus longan Lour., LA) is a kind of Chinese medicine, and it can improve intelligence attributed to entering the spleen-meridian. This study aimed to explore the therapeutic effects of LA on AD mice with spleen deficiency, and to understand anti-AD mechanism of LA.

MATERIAL AND METHODS

A mouse model of AD with spleen deficiency was established by D-gal (140 mg/kg, intraperitoneal injection) and AlCl₃ (20 mg/kg, intragastrical administration) in combination with an irregular diet for 60 days, in which mice in LA group were daily given LA (0.5, 1.0 or 2.0 g/kg). The anti-AD effects of LA were evaluated by the Morris water maze, enzyme-linked immunosorbent assay (ELISA), hematoxylin and eosin (H&E), Nissl, and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays. The anti-AD mechanism of LA was studied by using metabolomics, and the expressions of RAS/MEK/extracellular signal-regulated kinase (ERK) signaling pathway-related proteins were detected by Western blotting.

RESULTS

LA improved learning and memory abilities, superoxide dismutase (SOD) level, and form and number of Nissl bodies, while reduced the levels of Aβ₄₂, phosphorylated-tau (p-tau), reactive oxygen species (ROS), malondialdehyde (MDA), monoamine oxidase-B (MAO-B), histological injury, and apoptosis rate in AD group (P < 0.05, P < 0.01 or P < 0.001). The anti-AD mechanism of LA may be related to RAS/MEK/ERK and other signaling pathways, in which the expressions of RAS/MEK/ERK signaling pathway-related proteins significantly reduced (P < 0.05 or P < 0.01).

CONCLUSIONS

LA could improve the cognitive ability and reduce the pathologic impairment in AD mice, which might be partly mediated via inhibition of RAS/MEK/ERK singling pathway.

Neuroprotective Activity of Cerebrosides from Typhonium giganteum by Regulating Caspase-3 and Bax/Bcl-2 Signaling Pathways in PC12 Cells

An investigation of the potential neuroprotective natural product constituents of the rhizomes of Typhonium giganteum led to the isolation of two new cerebrosides, typhonosides E (1) and F (2), along with 11 known analogues (3-13). The structures of compounds 1 and 2 were elucidated by spectroscopic data interpretation. The activity of these compounds against glutamate-induced cell apoptosis was investigated in PC12 cells. All compounds exhibited such activity, which was related to the length of the fatty acyl chain. Among them, longan cerebroside II (11), with the longest fatty acyl chain, showed the most potent protective effect in PC12 cells from glutamate injury, with an EC₅₀ value of 2.5 μM. Moreover, at the molecular level, longan cerebroside II (11) downregulated the expression of caspase-9, caspase-3, and Bax, upregulated the expression of Bcl-2, and decreased the level of cytosolic cytochrome c in a concentration-dependent manner.

In vitro antibacterial, cytotoxic and antioxidant activities of plant Nephelium longan

The petroleum ether, chloroform and ethyl acetate fractions of ethanol extract of leaf and stem from the plant Nephelium longan (Fam-Sapindaceae) was subjected to antioxidant, antibacterial and cytotoxic activity. All the fractions showed potent antioxidant activity, of which the ethyl acetate and chloroform fraction of leaf demonstrated the strongest antioxidant activity with the IC50 value of 44.28 and 44.31 microg mL(-1), respectively. The petroleum ether extracts (500 microg disc(-1)) of leaf and stem of N. longan almost showed no activity against the tested pathogenic organisms except Escherichia coli. On the other hand, chloroform crude extracts of leaf and stem (500 microg disc(-1)) showed excellent antibacterial activity with the average zone of inhibition of 13-21 mm among the tested bacteria. Besides this, ethyl acetate crude extracts showed good activity against the growth of Sarcina lutea (20 mm), Vibrio mimicus (18 mm), Salmonella typhi (18 mm), E. coli (17 mm) and Staphylococcus aureus (14 mm). However, in the brine shrimp lethality bioassay, all the crude extracts of leaf and stem possessed considerable cytotoxic activity. It was evident that, the chloroform and ethyl acetate extracts of leaf and stem have significant cytotoxic potentials with the LC50 value of 8.802, 9.587, 9.248 and 10.45 microg mL(-1), respectively. Both the stem and leaf of the experimental plant have considerable antibacterial, cytotoxic and antioxidant properties which indicates that the plant have potent bioactive principles.

Methanol extract of Longanae Arillus augments pentobarbital-induced sleep behaviors through the modification of GABAergic systems

This experiment was performed to investigate whether methanol extract of Longanae Arillus (MELA) has hypnotic effects and/or enhances pentobarbital-induced sleep behaviors through the GABAergic systems. MELA prolonged sleep time and reduced sleep latency induced by pentobarbital similar to muscimol, a GABAA receptors agonist. MELA also increased sleep rate and sleep time in the combined administration with pentobarbital at the sub-hypnotic dosage and showed synergic effects with muscimol in potentiating sleep onset and enhancing sleep time induced by pentobarbital. However, MELA itself did not induce sleep at higher dose which was used in this experiment. In addition, both of MELA and pentobarbital increased chloride influx in primary cultured cerebellar granule cells. MELA increased GABAA receptors gamma-subunit expression and had no effect on the expression of alpha- and beta-subunits, and glutamic acid decarboxylase (GAD) in primary cultured cerebellar granule cells, showing different expression of subunits from pentobarbital. In conclusion, MELA itself does not induce sleep, but it augments pentobarbital-induced sleep behaviors through the modification of GABAergic systems.

A new cerebroside from fruits of Ailanthus altissima Swingle

A new cerebroside and three known cycloartan triterpenes were isolated from fruits of Ailanthus altissima Swingle. Their structures were identified as 1-O-beta-D-glucopyranosyl-(2S, 3R, 4E, 9E)-2-(2'R-hydroxyhexadecenoy)-4, 9-octadecadiene-1, 3-diol (1), 9, 19-cyclolanost-23 (Z)-ene-3beta, 25-diol (2), cycloart-25-ene-3beta, 24R-diol (3), and cycloart-25-ene-3beta, 24S-diol (4) by means of chemical and spectroscopic analysis. Compounds 2, 3, and 4 were isolated from genus Ailanthus for the first time. The analgesic activity of 1 was also evaluated.

Steryl esters and phenylethanol esters from Syringa komarowii

Three new steryl esters and a new phenylethanol ester, together with 22 known compounds were isolated from the aqueous ethanolic extract of the whole plants of Syringa komarowii. The new compounds were elucidated as stigmastane-3beta,6alpha-diol 3-O-tetradecanoate (1), stigmastane-3beta,6alpha-diol 3-O-palmitate (2), stigmastane-3beta,6alpha-diol 3-O-stearate (3), and 2-(4-hydroxyphenyl)-ethyl dotriacontanoate (4) on the basis of extensive spectral data and chemical evidences.

New ceramide from Alocasia macrorrhiza

A new ceramide alomacrorrhiza A was isolated from the ethanolic extract of the plant Alocasia macrorrhiza (L.) Schott. Its chemical structure was elucidated as (2S,3S,4R)-2N-[(2'R)-2'-hydroxy-hexacosanoyl]-tetradecane-1,3,4-triol based on extensive 1D, 2D NMR, EI-MS, FAB-MS, HR-FAB-MS spectroscopic data and chemical degradation studies.

A New Phenanthrene Glycoside and Other Constituents from Dioscorea opposita

Phytochemical investigation of the rhizome of Dioscorea opposita has led to the isolation of a new phenanthrene glycoside, 3,4,6-trihydroxyphenanthrene-3-O-beta-D-glucopyranoside (1), and five known compounds, soyacerebroside I (2), adenosine (3), beta-sitosterol (4), palmitic acid (5) and palmitoyloleoylphosphatidylcholine (6). Their structures were determined by spectroscopic methods, including 1D- and 2D-NMR. Compounds 1-6 exhibited no antifungal activity against the human pathogenic yeasts Candida albicans, C. glabrata and C. tropicalis.