Discrepancy Study of the Chemical Constituents of Panax Ginseng from Different Growth Environments with UPLC-MS-Based Metabolomics Strategy.

Panax ginseng (P. ginseng), the dried root and rhizome of P. ginseng C. A. Meyer, is widely used in many fields as dietary supplements and medicine. To characterize the chemical constituents in P. ginseng cultivated in different growth environments, a UPLC-TOF-MS method was established for qualitative analysis. Four hundred and eight ginsenosides, including 81 new compounds, were characterized in P. ginseng from different regions. Among the detected compounds, 361 ginsenosides were recognized in P. ginseng cultivated in the region of Monsoon Climate of Medium Latitudes, possessing the largest amount of ginsenosides in all samples. Furthermore, 41 ginsenosides in 12 batches of P. ginsengs were quantified with a UPLC-MRM-MS method, and P. ginsengs from different regions were distinguished via chemometric analysis. This study showed that the different environments have a greater influence on P. ginseng, which laid a foundation for further quality control of the herb.

Characterization of Ginsenosides from the Root of Panax ginseng by Integrating Untargeted Metabolites Using UPLC-Triple TOF-MS.

To compare the chemical distinctions of Panax ginseng Meyer in different growth environments and explore the effects of growth-environment factors on P. ginseng growth, an ultra-performance liquid chromatography-tandem triple quadrupole time-of-flight mass spectrometry (UPLC-Triple-TOF-MS/MS) was used to characterize the ginsenosides obtained by ultrasonic extraction from P. ginseng grown in different growing environments. Sixty-three ginsenosides were used as reference standards for accurate qualitative analysis. Cluster analysis was used to analyze the differences in main components and clarified the influence of growth environment factors on P. ginseng compounds. A total of 312 ginsenosides were identified in four types of P. ginseng, among which 75 were potential new ginsenosides. The number of ginsenosides in L15 was the highest, and the number of ginsenosides in the other three groups was similar, but it was a great difference in specie of ginsenosides. The study confirmed that different growing environments had a great influence on the constituents of P. ginseng, and provided a new breakthrough for the further study of the potential compounds in P. ginseng.

DNA methylation and histone deacetylation regulating insulin sensitivity due to chronic cold exposure.

In this study, we investigated the causal relationship between chronic cold exposure and insulin resistance and the mechanisms of how DNA methylation and histone deacetylation regulate cold-reduced insulin resistance. 46 adult male mice from postnatal day 90-180 were randomly assigned to control group and cold-exposure group. Mice in cold-exposure group were placed at temperature from -1 to 4 °C for 30 days to mimic chronic cold environment. Then, fasting blood glucose, blood insulin level and insulin resistance index were measured with enzymatic methods. Immunofluorescent labeling was carried out to visualize the insulin receptor substrate 2 (IRS2), Obese receptor (Ob-R, a leptin receptor), voltage-dependent anion channel protein 1 (VDAC1), cytochrome C (cytC), 5-methylcytosine (5-mC) positive cells in hippocampal CA1 area. Furthermore, the expressions of some proteins mentioned above were detected with Western blot. The results showed: ① Chronic cold exposure could reduce the insulin resistance index (P < 0.01) and increase the number of IRS2 positive cells and Ob-R positive cells in hippocampus (P < 0.01). ② The expressions of mitochondrial energy-relative proteins, VDAC1 and cytC, were higher in cold-exposure group than in control group with both immunohistochemical staining and Western blot (P < 0.01). ③ Chronic cold exposure increased DNA methylation and histone deacetylation in the pyramidal cells of CA1 area and led to an increase in the expression of histone deacetylase 1 (HDAC1) and DNA methylation relative enzymes (P < 0.01). In conclusion, chronic cold exposure can improve insulin sensitivity, with the involvement of DNA methylation, histone deacetylation and the regulation of mitochondrial energy metabolism. These epigenetic modifications probably form the basic mechanism of cold-reduced insulin resistance.

Application of UPLC-Triple TOF-MS/MS metabolomics strategy to reveal the dynamic changes of triterpenoid saponins during the decocting process of Asian ginseng and American ginseng.

Triterpenoid saponins are the main bioactive components contributed to the nutritional value of ginseng, and different process conditions will affect their content and quality. To study the holistic characterization and dynamic changes of triterpenoid saponins in Asian ginseng (ASG) and American ginseng (AMG) during soaking and decoction, a UPLC-Triple TOF-MS/MS-based metabolomics strategy was used to characterize and discover differential saponin markers. In total, 739 triterpenoid saponins (including 225 potential new saponins) were identified from ASG and AMG in untargeted metabolomics. Based on PCA and OPLS-DA, 51 and 48 saponin markers were screened from soaked and decocted ASG and AMG, respectively. Additionally, targeted metabolomics analysis and HCA of 22 ginsenoside markers suggested that decoction of ASG and AMG for 2 h to 4 h could significantly increase the contents of rare ginsenosides (G), such as G-Rg3, G-Rg5, G-F4. This study provides a scientific insight that high boiling combined with simmering enriches ASG and AMG extracts with rich rare ginsenosides that are more beneficial to human health.

Crosstalk between CYP2E1 and PPARα substrates and agonists modulate adipose browning and obesity.

Although the functions of metabolic enzymes and nuclear receptors in controlling physiological homeostasis have been established, their crosstalk in modulating metabolic disease has not been explored. Genetic ablation of the xenobiotic-metabolizing cytochrome P450 enzyme CYP2E1 in mice markedly induced adipose browning and increased energy expenditure to improve obesity. CYP2E1 deficiency activated the expression of hepatic peroxisome proliferator-activated receptor alpha (PPARα) target genes, including fibroblast growth factor (FGF) 21, that upon release from the liver, enhanced adipose browning and energy expenditure to decrease obesity. Nineteen metabolites were increased in Cyp2e1-null mice as revealed by global untargeted metabolomics, among which four compounds, lysophosphatidylcholine and three polyunsaturated fatty acids were found to be directly metabolized by CYP2E1 and to serve as PPARα agonists, thus explaining how CYP2E1 deficiency causes hepatic PPARα activation through increasing cellular levels of endogenous PPARα agonists. Translationally, a CYP2E1 inhibitor was found to activate the PPARα-FGF21-beige adipose axis and decrease obesity in wild-type mice, but not in liver-specific Ppara-null mice. The present results establish a metabolic crosstalk between PPARα and CYP2E1 that supports the potential for a novel anti-obesity strategy of activating adipose tissue browning by targeting the CYP2E1 to modulate endogenous metabolites beyond its canonical role in xenobiotic-metabolism.

Mouse induced pluripotent stem cells-derived Alzheimer's disease cerebral organoid culture and neural differentiation disorders.

Alzheimer's disease (AD) is a progressive neurodegenerative disease, characterized by cognitive impairment. However, the pathogenesis of AD are very complicated, and the theories of Aß and neurofibrillary tangles cannot explain all pathological alterations and clinical symptoms. Here, we used three-dimensional (3D) neural organoids culture derived from mouse induced pluripotent stem cells (iPSCs) to investigate the pathological mechanisms of AD. In this study, AD cerebral organoids were generated by overexpressing familial AD mutations (APP and PS1 genes) in mouse induced pluripotent stem cells, so that the early pathogenesis of AD could be investigated well with protein and cellular phenotype analyses. The results showed that AD cerebral organoids appeared some AD pathological alterations, and high levels of Aß and p-Tau were induced as well. Furthermore, the number of GFAP-positive astrocytes and glutamatergic excitatory neurons increased significantly, but the number of GABAergic interneurons decreased. In conclusion, we suggest that cerebral organoids are a suitable AD model for scientific study, and that will provide us a novel insight into the understanding of the pathogenesis of AD.

Synaptic aging disrupts synaptic morphology and function in cerebellar Purkinje cells.

Synapses are key structures in neural networks, and are involved in learning and memory in the central nervous system. Investigating synaptogenesis and synaptic aging is important in understanding neural development and neural degeneration in diseases such as Alzheimer disease and Parkinson's disease. Our previous study found that synaptogenesis and synaptic maturation were harmonized with brain development and maturation. However, synaptic damage and loss in the aging cerebellum are not well understood. This study was designed to investigate the occurrence of synaptic aging in the cerebellum by observing the ultrastructural changes of dendritic spines and synapses in cerebellar Purkinje cells of aging mice. Immunocytochemistry, DiI diolistic assays, and transmission electron microscopy were used to visualize the morphological characteristics of synaptic buttons, dendritic spines and synapses of Purkinje cells in mice at various ages. With synaptic aging in the cerebellum, dendritic spines and synaptic buttons were lost, and the synaptic ultrastructure was altered, including a reduction in the number of synaptic vesicles and mitochondria in presynaptic termini and smaller thin specialized zones in pre- and post-synaptic membranes. These findings confirm that synaptic morphology and function is disrupted in aging synapses, which may be an important pathological cause of neurodegenerative diseases.

CD226 reduces endothelial cell glucose uptake under hyperglycemic conditions with inflammation in type 2 diabetes mellitus.

CD226 is a co-stimulatory adhesion molecule found on immune and endothelial cells. Here, we evaluated a possible role for CD226 in inhibiting glucose uptake in isolated human umbilical vein endothelial cells (HUVECs) and in wild-type (WT) and CD226 knockout (KO) mice with high-fat diet (HFD)-induced type 2 diabetes (T2DM). CD226 expression increased under hyperglycemic conditions in the presence of TNF-α. Furthermore, CD226 knockdown improved glucose uptake in endothelial cells, and CD226 KO mice exhibited increased glucose tolerance. Levels of soluble CD226 in plasma were higher in T2DM patients following an oral glucose tolerance test (OGTT) than under fasting conditions. Our results indicate that low-grade inflammation coupled with elevated blood glucose increases CD226 expression, resulting in decreased endothelial cell glucose uptake in T2DM.