Effect of Ergothioneine on 7-Ketocholesterol-Induced Endothelial Injury.

Ergothioneine (ET) is a naturally occurring antioxidant that is synthesized by non-yeast fungi and certain bacteria. ET is not synthesized by animals, including humans, but is avidly taken up from the diet, especially from mushrooms. In the current study, we elucidated the effect of ET on the hCMEC/D3 human brain endothelial cell line. Endothelial cells are exposed to high levels of the cholesterol oxidation product, 7-ketocholesterol (7KC), in patients with cardiovascular disease and diabetes, and this process is thought to mediate pathological inflammation. 7KC induces a dose-dependent loss of cell viability and an increase in apoptosis and necrosis in the endothelial cells. A relocalization of the tight junction proteins, zonula occludens-1 (ZO-1) and claudin-5, towards the nucleus of the cells was also observed. These effects were significantly attenuated by ET. In addition, 7KC induces marked increases in the mRNA expression of pro-inflammatory cytokines, IL-1ß IL-6, IL-8, TNF-α and cyclooxygenase-2 (COX2), as well as COX2 enzymatic activity, and these were significantly reduced by ET. Moreover, the cytoprotective and anti-inflammatory effects of ET were significantly reduced by co-incubation with an inhibitor of the ET transporter, OCTN1 (VHCL). This shows that ET needs to enter the endothelial cells to have a protective effect and is unlikely to act via extracellular neutralizing of 7KC. The protective effect on inflammation in brain endothelial cells suggests that ET might be useful as a nutraceutical for the prevention or management of neurovascular diseases, such as stroke and vascular dementia. Moreover, the ability of ET to cross the blood-brain barrier could point to its usefulness in combatting 7KC that is produced in the CNS during neuroinflammation, e.g. after excitotoxicity, in chronic neurodegenerative diseases, and possibly COVID-19-related neurologic complications.

Quality evaluation of Bolbostemmatis Rhizoma by UPLC fingerprint combined with QAMS / 中国中药杂志

The present study was performed to establish the UPLC fingerprints of Bolbostemmatis Rhizoma and determine the contents of three saponins by quantitative analysis of multi-components by single marker(QAMS), and provide basis for quality evaluation of Bolbostemmatis Rhizoma. The analysis was carried out on an analytical column of Waters Cortecs T3(2.1 mm×100 mm,1.6 μm)with gradient elution by acetonitrile-0.1% phosphoric acid solution, at a flow rate of 0.3 mL·min~(-1). The detection wavelength was 203 nm, the column temperature was 30 ℃ and the injection volume was 1 μL. The UPLC fingerprints of Bolbostemmatis Rhizoma were established and evaluated by similarity calculation, cluster analysis and principal component analysis. The relative calibration factors of toberoside B and toberoside C were determined with toberoside A as internal reference. The content was calculated by relative calibration factors to develop a method of QAMS. Comparing the results of QAMS with those of ESM, the accuracy and feasibility of one-eva-luation and multi-evaluation can be determined. RESULTS:: showed that the fingerprints of 19 batches of Bolbostemmatis Rhizoma have four common peaks with similarities ranging from 0.754 to 1.000. Cluster analysis and principal component analysis classified 19 batches of Bolbostemmatis Rhizoma into three categories, which was consistent with the similarity evaluation results. The relative deviation between the content of tubeicosides B and C in 19 batches of Bolbostemmatis Rhizoma determined by QAMS and ESM is less than 5.0%, indicating that there was no significant difference between the two methods. Therefore, the UPLC fingerprints combined with QAMS and similarity evaluation can be effectively used to evaluate the quality of Bolbostemmatis Rhizoma.