ABSTRACT
Seventeen minor triterpenoid acids (1-17) were isolated from an aqueous decoction of Uncaria rhynchophylla by a combinatory application of column chromatography using multiple stationary phases, including macroporous adsorbent resin, MCI resin, Sephadex LH-20, Toyopearl HW-40C, silica gel, and C18 reversed phase silica gel, combined with separation techniques of flash chromatography (FC) and high performance liquid chromatography (HPLC). Their structures were determined by analysis of HR-ESI-MS, UV, CD, and IR as well as 1D and 2D NMR spectroscopic data, of which eight new compounds (1-8) are named successively uncarinic acids Q-X, while the structures of 2 and 7 were confirmed by single crystal X-ray diffraction. In the in vitro assays, 27-hydroxyolean-12-en-28-oic acid (17) inhibited TGF-β-induced HSC-T6 cell activation at the concentration of 5 μmol·L-1.
ABSTRACT
On the basis of the Uncaria transcriptome, specific primers were designed for UrSTR. The full-length cDNA of UrSTR (GeneBank: OL310251) was 1 541 bp, encoding 345 amino acid residues, and the promoter region sequence of UrSTR (GeneBank: OL310252) was 1 179 bp. Phylogenetic tree is revealed that UrSTR had a closest relationship with STR from Ophiorrhiza pumila and Ophiorrhiza japonica. Localization of UrSTR protein is revealed located in the vacuole membrane. Plant-care analysis indicated that the promoter region sequence of UrSTR, covering multiple light, stress and hormone-response cis-regulatory elements, and verified transcriptional activity. The results of SDS-PAGE show that pET-28a-UrSTR recombinant protein was successfully expressed, and the size was anticipated. The UrSTR prokaryotic expression system needs to be optimized in the later stage. The research lays the foundation for further purification to study its structure and functional characterization of the UrSTR protein.
ABSTRACT
Five new megastigmanes (1-5) were isolated from a decoction of Uncaria rhynchophylla by separation techniques of column chromatography using a combination of multiple stationary phases, including macroporous adsorbent resin, MCI resin, silica gel, Sephadex LH-20, and Toyopearl HW-40F, and reversed phase HPLC. Their structures were characterized by spectroscopic data analysis of HR-ESI-MS, NMR, and CD, in combination with Mosher's mothed as well as ECD and NMR calculations. The new compounds were named uncarphyllonone A (1), uncarphyllonols A (2) and B (3), and uncarphabscisic acids A (4) and B (5). Although the structures of 3 and 4 were previously reported, the reported NMR spectroscopic data were incorrect or do not support the assigned structures in literatures. This is also the first report of discovery of new megastigmane natural products from the Uncaria genus.
ABSTRACT
In this paper, the lipidomics was used to analyze the changes to address how Uncaria interrupts lipid metabolism in the liver of spontaneously hypertensive rats, and to explore the mechanism of action of Uncaria. All the experiments were approved by the animal protection and use committee of Shandong University of Traditional Chinese Medicine. UHPLC-Q Extractive orbitrap high-resolution mass spectrometry was used to collect lipid metabolite information of the rat livers. Through pattern recognition, matters with noticeable differences were recognized. Mass spectrum and data base searching helped to identify the potential biomarkers. Pattern recognition results indicated that the rats from control versus SHR group showed clear differences. Compared with the rats from the control group, there are decreases in sphosphatidylcholine, phosphatidic acid, diacylglycerol and sphingomyelin in rats from the SHR group, however lysophosphatidylcholine, triglyceride, linoleic acid, arachidonic acid and ceramide are increased. Uncaria could regulate the disorder of lipid metabolism by interfering with glycerophospholipid, sphingolipid, linoleic acid, and arachidonic acid metabolic pathways. This study provided the mechanistic understanding of the impact of Uncaria on lipid metabolism and revealed the lipid metabolism pathways affected to offer the explanation for the complex mechanism of action.
ABSTRACT
Five alkaloids were isolated from a decoction of Uncaria rhynchophylla by a combination of various chromatographic techniques, including macroporous adsorbent resin, MCI resin, silica gel, Sephadex LH-20, and reversed phase HPLC. Their structures were characterized by comprehensive analyses of spectroscopic data as monoterpene indole alkaloids (+)-(7R)-3-oxo-7-hydroxy-3,7-seco-dihydrorhynchohylline (1), (+)-(7S)-3-oxo-7-hydroxy-3,7-seco-dihydrorhyncho-hylline (2), (+)-(7R)-3-oxo-7-hydroxy-3,7-seco-rhynchohylline (3) and (+)-(7S)-3-oxo-7-hydroxy-3,7-seco-rhynchohylline (4), and a β-carboline alkaloid 1,2,3,4-tetrahydro-1-oxo-β-carboline (5). Among them, 1 and 2 are new compounds, 3 and 4 are new natural products that were semi-synthesized from isorhynchohylline with incorrect specific rotations, and 5 is isolated for the first time from the genus Uncaria.