Quinic acid derivatives from Saussurea triangulata attenuates glutamate-induced neurotoxicity in primary cultured rat cortical cells

Abstract

The leaves of Saussurea triangulata (Compositae) have been eaten with rice as a wrapping vegetable for preventing neuroaging. However, the components responsible for the neuroprotective effects of S. triangulata still remain unidentified. In the process of investigating the neuroprotective activity of S. triangulata, we found that a methanol extract of S. triangulata exhibited significant protection against glutamate-induced toxicity in primary cultured rat cortical cells. Three quinic acid derivatives were isolated from the n-BuOH fraction of S. triangulata. Among these three quinic acid derivatives, methyl 5-caffeoylquinic acid (3) exhibited significant neuroprotective activities against glutamate-induced toxicity exhibiting cell viability of about 50%, at concentrations ranging from 0.1 mM to 10 mM. Therefore, the neuroprotective effect of S. triangulata might be due to the inhibition of glutamate-induced toxicity by the quinic acid derivatives from S. triangulata.

Current Advances in Naturally Occurring Caffeoylquinic Acids: Structure, Bioactivity, and Synthesis

“…The bioassay-guided isolation led to the identification of 5-CQA methyl ester (10) from the n-BuOH fraction of Saussurea triangulata (Compositae). 108 Compound 10 exhibited potent neuroprotective effects against glutamateinduced primary cultured rat cortical cell toxicity at 1 μM (46.2 ± 1.5% cell viability). ceae), a plant used as Chinese folk medicine, were shown to prevent glutamate-induced primary cultures of rat cerebral cortical neuron death by restraining the increase of Ca 2+ and the production of reactive oxygen species (ROS) (concentration range of 0.1−5 μM).…”

“…In another report, three new 4,5-DCQA derivatives (92−94), featuring different moieties at C-1, together with five known CQA derivatives were identified. 82 Their free radical scavenging activities were performed by DPPH, ABTS, and ferric reducing antioxidant power (FRAP) assays, and the abilities of these compounds increased in the order 5-CQA (9) < DCQA derivatives (91−94) < DCQAs (71 and 75) < TCQA (108). These results suggested that the antioxidant ability of CQAs was associated with the number of caffeoyl groups.…”

“…129 Moreover, these two compounds displayed inhibitory activities against the synthesis or release of monocyte chemoattractant protein 3 in a dose-dependent manner. Interestingly, 3,4,5-TCQA (108) was not able to inhibit PGE2 production both in vitro and in vivo. 130 However, another report by Motaal et al 131 suggested that compound 108 from Solidago virgaurea L. (Asteraceae) showed significant inhibition of the edema volume of paw at a dose of 50 mg/kg in a carrageenaninduced rat model.…”

“…The injection of 25 and 50 mg/kg of compound 75 in mice significantly improved the convulsions induced by pentylenetetrazole. The bioassay-guided isolation led to the identification of 5-CQA methyl ester ( 10 ) from the n -BuOH fraction of Saussurea triangulata (Compositae) . Compound 10 exhibited potent neuroprotective effects against glutamate-induced primary cultured rat cortical cell toxicity at 1 μM (46.2 ± 1.5% cell viability).…”

How to identify and discriminate between the methyl quinates of chlorogenic acids by liquid chromatography–tandem mass spectrometry

“…Three isomers were detected at m/z 557 and they were assigned as methyl diferuloylquinates (18)(19)(20). From the previous discussion of methyl quinates, it is generalized that the most hydrophilic isomer is methyl 3,4-diferuloylquinate 18 which produced the MS 2 (Fig.…”