Comprehensive Identification of Ginsenosides in the Roots and Rhizomes of Panax ginseng Based on Their Molecular Features-Oriented Precursor Ions Selection and Targeted MS/MS Analysis.

Panax ginseng is widely used in Asian countries and its active constituents-ginsenosides-need to be systematically studied. However, only a small part of ginsenosides have been characterized in the roots and rhizomes of panax ginseng (RRPG) up to date, mainly because of a lack of the fragmentation ions of many more ginsenosides. In order to comprehensively identify ginsenosides in RRPG, molecular features of ginsenosides orienting precursor ions selection and targeted tandem mass spectrometry (MS/MS) analysis strategy were proposed in our study, in which the precursor ions were selected according to the molecular features of ginsenosides irrespective of their peak abundances, and targeted MS/MS analysis was then performed to obtain their fragmentation ions for substance characterization. Using this strategy, a total of 620 ginsenosides were successfully characterized in RRPG, including 309 protopanaxadiol-type ginsenosides, 258 protopanaxatriol-type ginsenosides and 53 oleanane-type ginsenosides. It is worth noting that, except for the known aglycones mass-to-charge ratio (m/z) 459, 475 and 455, twelve other aglycones, including m/z 509, 507, 493, 491, 489, 487, 477, 473, 461, 457, 443 and 441, were first reported in our experiment and they were probably the derivatizations of the protopanaxatriol and protopanaxadiol. Our study will not only help people to improve the cognition of ginsenosides in RRPG, but will also play a guiding and reference role for the isolation and characterization of potentially new ginsenosides from RRPG.

Screening of Potential α-Glucosidase Inhibitors from the Roots and Rhizomes of Panax Ginseng by Affinity Ultrafiltration Screening Coupled with UPLC-ESI-Orbitrap-MS Method.

Panax ginseng was a traditional Chinese medicine with various pharmacological activities and one of its important activities was hypoglycemic activity; therefore, panax ginseng has been used in China as an adjuvant in the treatment of diabetes mellitus. In vivo and in vitro tests have revealed that ginsenosides, which are derived from the roots and rhizomes of panax ginseng have anti-diabetic effects and produce different hypoglycemic mechanisms by acting on some specific molecular targets, such as SGLT1, GLP-1, GLUTs, AMPK, and FOXO1. α-Glucosidase is another important hypoglycemic molecular target, and its inhibitors can inhibit the activity of α-Glucosidase so as to delay the absorption of dietary carbohydrates and finally reduce postprandial blood sugar. However, whether ginsenosides have the hypoglycemic mechanism of inhibiting α-Glucosidase activity, and which ginsenosides exactly attribute to the inhibitory effect as well as the inhibition degree are not clear, which needs to be addressed and systematically studied. To solve this problem, affinity ultrafiltration screening coupled with UPLC-ESI-Orbitrap-MS technology was used to systematically select α-Glucosidase inhibitors from panax ginseng. The ligands were selected through our established effective data process workflow based on systematically analyzing all compounds in the sample and control specimens. As a result, a total of 24 α-Glucosidase inhibitors were selected from panax ginseng, and it was the first time that ginsenosides were systematically studied for the inhibition of α-Glucosidase. Meanwhile, our study revealed that inhibiting α-Glucosidase activity probably was another important mechanism for ginsenosides treating diabetes mellitus. In addition, our established data process workflow can be used to select the active ligands from other natural products using affinity ultrafiltration screening.

Effect of 2″-O-Rhamnosyl Icariside II, Baohuoside I and Baohuoside II in Herba Epimedii on Cytotoxicity Indices in HL-7702 and HepG2 Cells.

Herba Epimedii, a commonly used Chinese medicine, has attracted much attention recently because of its potential hepatotoxic effects. 2″-O-Rhamnosyl icariside II, baohuoside I and baohuoside II are the main components of Herba Epimedii, and previous research indicates that these three compounds are related to the hepatotoxicity of Herba Epimedii. To test this idea, in this study, HL-7702 and HepG2 cells were chosen as the in vitro models and the influences of these three compounds on a series of cytotoxicity indices, including ALT, AST, LDH, SOD, GSH, MDA, ROS and MMP, were determined. The results showed that at certain concentrations, the three compounds had different effects on the indices. Among them, baohuoside I at high concentration (32 µg/mL) displayed more significant cytotoxicity than the other two compounds; therefore, it was inferred to be more closely correlated with the liver injury induced by Herba Epimedii combined with the previous study, and its toxic mechanisms may be involved in increasing oxidative stress and inducing apoptosis. The findings of this study may provide evidence of the toxic composition of Herba Epimedii to preliminarily discuss the toxic mechanisms and provide improved guidance for its clinical safety.

Astragaloside IV protects rat retinal capillary endothelial cells against high glucose-induced oxidative injury.

AIM: Diabetic retinopathy is a microvascular complication of diabetes that leads to blindness. Hyperglycemia causes oxidative stress, which is an important cause in the pathogenesis of microangiopathy. The aim of this study was to investigate the potential protective effects of astragaloside IV (AS-IV) in retinal capillary endothelial cells (RCECs) incubated with high glucose conditions. METHODS AND RESULTS: Based on rat RCECs cultured with high glucose (30 mM) in vitro, a significant increase in cell viability in rat RCECs incubated with both AS-IV and high glucose for 48 or 72 h by MTT assay. The increased viability was accompanied by decreased glucose transporter-1 expression using immunofluorescent assay. Meanwhile, AS-IV reduced intracellular hydrogen peroxide and superoxide, decreased mitochondrial reactive oxygen species in rat RCECs with high glucose by the fluorescent probes, and lowered malondialdehyde levels. In addition, AS-IV increased the activities of total superoxide dismutase, MnSOD, catalase, and glutathione peroxidase. The glutathione content also increased after AS-IV treatment. Furthermore, AS-IV reduced NADPH oxidase 4 expression by western blot method. CONCLUSION: These results suggest that the main mechanism underlying the protective effects of AS-IV in high glucose-injured RCECs may be related to its antioxidative function.

[Concentration and Size Distribution Characteristics of Culturable Bioaerosols at Various Air Quality Levels During Fall and Winter in Xi'an, China].

The concentration and size distribution of culturable bacteria and fungi were studied in Xi'an city at various air quality levels. The culturable bioaerosols were collected by an Andersen bioaerosol aerosol sampler between Sept. 2014 and Jan. 2015. Principal component analysis and multiple linear regressions were applied to link the concentrations with meteorological conditions including ambient temperature and relative humidity, as well as the levels of air pollutants such as PM2.5, PM10, NO2, SO2, and O3. These measured results showed that the concentration of culturable bacteria and fungi were in the ranges of 97-1909 CFU·m-3 and 92-1737 CFU·m-3, respectively. The concentrations of culturable bioaerosols increased along with a deterioration in air quality. The size distribution of the bacteria migrated to coarse particles. Fungal aerosols showed a normal distribution at low pollution levels, while for a high levels, they preferenced fine particles. Results from the principal component analysis (PCA) indicate that the concentration of culturable bioaerosols is mainly influenced by haze, solar radiation, and relative humidity. Multiple linear regression analysis showed that bacterial aerosol concentrations are positively correlated with haze (P<0.05) and relative humidity, while no significant negative correlations with solar radiation exists. Fungal aerosol concentrations did not have significant positive correlations with haze, solar radiation, or relative humidity. The results of this study will provide basic data for evaluating the effects of bioaerosols on human health and the environment.