[A new xanthone from hulls of Garcinia mangostana and its cytotoxic activity].

Eight compounds were isolated from ethyl acetate fraction of 80% ethanol extract of the hulls of Garcinia mangostana by silica gel, Sephadex LH-20 column chromatography, as well as prep-HPLC methods. By HR-ESI-MS, MS, 1D and 2D NMR spectral analyses, the structures of the eight compounds were identified as 16-en mangostenone E(1), α-mangostin(2), 1,7-dihydroxy-2-(3-methy-lbut-2-enyl)-3-methoxyxanthone(3), cratoxyxanthone(4), 2,6-dimethoxy-para-benzoquinone(5), methyl orselinate(6), ficusol(7), and 4-(4-carboxy-2-methoxyphenoxy)-3,5-dimethoxybenzoic acid(8). Compound 1 was a new xanthone, and compound 4 was a xanthone dimer, compound 5 was a naphthoquinone. All compounds were isolated from this plant for the first time except compounds 2 and 3. Cytotoxic bioassay suggested that compounds 1, 2 and 4 possessed moderate cytotoxicity, suppressing HeLa cell line with IC_(50) va-lues of 24.3, 35.5 and 17.1 µmol·L~(-1), respectively. Compound 4 also could suppress K562 cells with an IC_(50) value of 39.8 µmol·L~(-1).

[Effect of guarana on lipid metabolism in obese rats: a study based on lipidomics].

This study investigated the effect of guarana on plasma lipid metabolites in obese rats and analyzed its mechanism in the treatment of dyslipidemia in obesity. High-fat diet was used to establish obese rat models, and the therapeutic effect of guarana on obese rats was evaluated by measuring body weight, white fat, liver weight, and lipid content, as well as observing liver histomorphology. Lipid metabolites in plasma of rats in each group were detected by UHPLC-Q-TOF-MS lipidomics. The protein expressions of fatty acid synthase, acetyl-CoA carboxylase 1, triglyceride synthesis enzyme, carnitine palmitoyltransferase Ⅰ, and acetyl-coenzyme A acyltransferase 2 in rat liver were detected using Western blot. The results revealed that guarana significantly reduced body weight, white fat, and liver weight of obese rats due to high-fat diet, and alleviated dyslipidemia and liver steatosis. Lipidomics showed that some triglycerides and phospholipids were significantly elevated in the high-fat model group, and part of them was reduced after guarana treatment. Western blot found that guarana inhibited the expression of hepatic fatty acid and triglyceride synthesis-related proteins and increased the expression of fatty acid ß-oxidation-related proteins. Abnormalities in triglyceride and phospholipid metabolism are the main characteristics of plasma lipid metabolism in obese rats induced by high-fat diet. Guarana may regulate partial triglyceride and phospholipid metabolism by inhibiting hepatic fatty acid and triglyceride synthesis and increasing fatty acid ß-oxidation, thereby improving rat obesity and dyslipidemia.

Analysis of Regulatory Mechanism of AcrB and CpxR on Colistin Susceptibility Based on Transcriptome and Metabolome of Salmonella Typhimurium.

With the increasing and inappropriate use of colistin, the emerging colistin-resistant isolates have been frequently reported during the last few decades. Therefore, new potential targets and adjuvants to reverse colistin resistance are urgently needed. Our previous study has confirmed a marked increase of colistin susceptibility (16-fold compared to the wild-type Salmonella strain) of cpxR overexpression strain JSΔacrBΔcpxR::kan/pcpxR (simplified as JSΔΔ/pR). To searching for potential new drug targets, the transcriptome and metabolome analysis were carried out in this study. We found that the more susceptible strain JSΔΔ/pR displayed striking perturbations at both the transcriptomics and metabolomics levels. The virulence-related genes and colistin resistance-related genes (CRRGs) were significantly downregulated in JSΔΔ/pR. There were significant accumulation of citrate, α-ketoglutaric acid, and agmatine sulfate in JSΔΔ/pR, and exogenous supplement of them could synergistically enhance the bactericidal effect of colistin, indicating that these metabolites may serve as potential adjuvants for colistin therapy. Additionally, we also demonstrated that AcrB and CpxR could target the ATP and reactive oxygen species (ROS) generation, but not proton motive force (PMF) production pathway to potentiate antibacterial activity of colistin. Collectively, these findings have revealed several previously unknown mechanisms contributing to increased colistin susceptibility and identified potential targets and adjuvants for potentiating colistin treatment of Salmonella infections. IMPORTANCE Emergence of multidrug-resistant (MDR) Gram-negative (G-) bacteria have led to the reconsideration of colistin as the last-resort therapeutic option for health care-associated infections. Finding new drug targets and strategies against the spread of MDR G- bacteria are global challenges for the life sciences community and public health. In this paper, we demonstrated the more susceptibility strain JSΔΔ/pR displayed striking perturbations at both the transcriptomics and metabolomics levels and revealed several previously unknown regulatory mechanisms of AcrB and CpxR on the colistin susceptibility. Importantly, we found that exogenous supplement of citrate, α-ketoglutaric acid, and agmatine sulfate could synergistically enhance the bactericidal effect of colistin, indicating that these metabolites may serve as potential adjuvants for colistin therapy. These results provide a theoretical basis for finding potential new drug targets and adjuvants.

Synergistic antibacterial activity of baicalin and EDTA in combination with colistin against colistin-resistant Salmonella.

The emergence and rapid spread of multidrug resistant (MDR) Gram-negative bacteria have posed a serious threat to global health and security. Because of the time-consuming, high cost and high risk of developing new antibiotics, a significant method is to use antibiotic adjuvants to revitalize the existing antibiotics. The purpose of the study is to research the traditional Chinese medicine baicalin with the function of inhibiting the efflux pump and EDTA whether their single or combination can increase the activity of colistin against colistin-resistant Salmonella in vitro and in vivo, and to explore its molecular mechanisms. In vitro antibacterial experiments, we have observed that baicalin and EDTA alone could enhance the antibacterial activity of colistin. At the same time, the combination of baicalin and EDTA also showed a stronger synergistic effect on colistin, reversing the colistin resistance of all Salmonella strains. Molecular docking and RT-PCR results showed that the combination of baicalin and EDTA not only affected the expression of mcr-1, but also was an effective inhibitor of MCR-1. In-depth synergistic mechanism analysis revealed that baicalin and EDTA enhanced colistin activity through multiple pathways, including accelerating the tricarboxylic acid cycle (TCA cycle), inhibiting the bacterial antioxidant system and lipopolysaccharide (LPS) modification, depriving multidrug efflux pump functions and attenuating bacterial virulence. In addition, the combinational therapy of colistin, baicalin and EDTA displayed an obvious reduction in bacterial loads cfus of liver and spleen compared with monotherapy and 2-drug combination therapy. In conclusion, our study indicates that the combination of baicalin and EDTA as a novel colistin adjuvant can provide a reliable basis for formulating the therapeutic regimen for colistin resistant bacterial infection.

[Chemical constituents from Salacia polysperma].

Nine compounds were isolated from the 90% ethanol extract of Salacia polysperma by silica gel, Sephadex LH-20 column chromatography, together with preparative HPLC methods. Based on HR-ESI-MS, MS, 1D and 2D NMR spectral analyses, the structures of the nine compounds were identified as 28-hydroxy wilforlide B(1), wilforlide A(2), 1ß,3ß-dihydroxyurs-9(11),12-diene(3),(-)-epicatechin(4),(+)-catechin(5),(-)-4'-O-methyl-ent-galloepicatechin(6), 3-hydroxy-1-(4-hydroxy-3-methoxy-phenyl)propan-1-one(7),(-)-(7S,8R)-4-hydroxy-3,3',5'-trimethoxy-8',9'-dinor-8,4'-oxyneoligna-7,9-diol-7'-aldehyde(8), and vanillic acid(9). Compound 1 is a new oleanane-type triterpene lactone. Compounds 1, 3, 4, 7-9 were isolated from the Salacia genus for the first time. All compounds were assayed for their α-glucosidase inhibitory activity. The results suggested that compound 8 exhibited moderate α-glucosidase inhibitory activity, with an IC_(50) value of 37.2 µmol·L~(-1), and the other compounds showed no α-glucosidase inhibitory activity.

[Study on time-toxicity relationship and mechanism of Gardeniae Fructus extract on hepatoxicity in rats based on proteomics].

To study the time-toxicity relationship and mechanism of Gardeniae Fructus extract on the hepatoxicity in rats. Rats were randomly divided into C group(0 day), D5 group(5 days), D12 group(12 days), D19 group(19 days), and D26 group(7 days recovery after 19 days of administration). The rats in normal group received normal saline through intragastric administration, and the rats in other groups received 10 g·kg~(-1 )Gardeniae Fructus extract through intragastric administration. After the final administration, the livers were collected. Hematoxylin-eosin staining was used to observe the histopathological changes in the liver tissue. Total liver proteins were extracted for proteomic analysis, detected by the Nano-ESI liquid-mass spectrometry system and identified by Protein Disco-very software. SIEVE software was used for relative quantitative and qualitative analysis of proteins. The protein-protein interaction network was constructed based on STRING. Cytoscape software was used for cluster analysis of differential proteins. Kyoto encyclopedia of genes and genomes(KEGG) database was used to perform enrichment signal pathway analysis. Pearson correlation analysis was performed for the screened differential protein expression and liver pathology degree score. The results showed that the severity of liver injury in D5, D12 and D19 groups was significantly higher than that in group C. The degree of liver damage in D5 group was slightly higher than that in D12 and D19 groups, with no significant difference between group D26 and group C. Totally 147 key differential proteins have been screened out by proteomics and mainly formed 6 clusters, involving in drug metabolism pathways, retinol metabolism pathways, proteasomes, amino acid biosynthesis pathways, and glycolysis/gluconeogenesis pathways. The results of Pearson correlation analysis indicated that differential protein expressions had a certain temporal relationship with the change of liver pathological degree. The above results indicated that the severity of liver damage caused by Gardeniae Fructus extract did not increase with time and would recover after drug with drawal. The above pathways may be related to the mechanism of liver injury induced by Gardeniae Fructus extract.

A novel palmitic acid hydroxy stearic acid (5-PAHSA) plays a neuroprotective role by inhibiting phosphorylation of the m-TOR-ULK1 pathway and regulating autophagy.

AIMS: Type 2 diabetes mellitus (T2DM) can lead to brain dysfunction and a series of neurological complications. Previous research demonstrated that a novel palmitic acid (5-PAHSA) exerts effect on glucose tolerance and chronic inflammation. Autophagy was important in diabetic-related neurodegeneration. The aim of the present study was to investigate whether 5-PAHSA has specific therapeutic effects on neurological dysfunction in diabetics, particularly with regard to autophagy. METHODS: 5-PAHSA was successfully synthesized according to a previously described protocol. We then carried out a series of in vitro and in vivo experiments using PC12 cells under diabetic conditions, and DB/DB mice, respectively. PC12 cells were treated with 5-PAHSA for 24 h, while mice were administered with 5-PAHSA for 30 days. At the end of each experiment, we analyzed glucolipid metabolism, autophagy, apoptosis, oxidative stress, cognition, and a range of inflammatory factors. RESULTS: Although there was no significant improvement in glucose metabolism in mice administered with 5-PAHSA, ox-LDL decreased significantly following the administration of 5-PAHSA in serum of DB/DB mice (p < 0.0001). We also found that the phosphorylation of m-TOR and ULK-1 was suppressed in both PC12 cells and DB/DB mice following the administration of 5-PAHSA (p < 0.05 and p < 0.01), although increased levels of autophagy were only observed in vitro (p < 0.05). Following the administration of 5-PAHSA, the concentration of ROS decreased in PC12 cells and the levels of CRP increased in high-dose group of 5-PAHSA (p < 0.01). There were no significant changes in terms of apoptosis, other inflammatory factors, or cognition in DB/DB mice following the administration of 5-PAHSA. CONCLUSION: We found that 5-PAHSA can enhance autophagy in PC12 cells under diabetic conditions. Our data demonstrated that 5-PAHSA inhibits phosphorylation of the m-TOR-ULK1 pathway and suppressed oxidative stress in PC12 cells, and exerted influence on lipid metabolism in DB/DB mice.

Study on time-toxicity relationship and mechanism of Gardeniae Fructus extract on hepatoxicity in rats based on proteomics / 中国中药杂志

To study the time-toxicity relationship and mechanism of Gardeniae Fructus extract on the hepatoxicity in rats. Rats were randomly divided into C group(0 day), D5 group(5 days), D12 group(12 days), D19 group(19 days), and D26 group(7 days recovery after 19 days of administration). The rats in normal group received normal saline through intragastric administration, and the rats in other groups received 10 g·kg~(-1 )Gardeniae Fructus extract through intragastric administration. After the final administration, the livers were collected. Hematoxylin-eosin staining was used to observe the histopathological changes in the liver tissue. Total liver proteins were extracted for proteomic analysis, detected by the Nano-ESI liquid-mass spectrometry system and identified by Protein Disco-very software. SIEVE software was used for relative quantitative and qualitative analysis of proteins. The protein-protein interaction network was constructed based on STRING. Cytoscape software was used for cluster analysis of differential proteins. Kyoto encyclopedia of genes and genomes(KEGG) database was used to perform enrichment signal pathway analysis. Pearson correlation analysis was performed for the screened differential protein expression and liver pathology degree score. The results showed that the severity of liver injury in D5, D12 and D19 groups was significantly higher than that in group C. The degree of liver damage in D5 group was slightly higher than that in D12 and D19 groups, with no significant difference between group D26 and group C. Totally 147 key differential proteins have been screened out by proteomics and mainly formed 6 clusters, involving in drug metabolism pathways, retinol metabolism pathways, proteasomes, amino acid biosynthesis pathways, and glycolysis/gluconeogenesis pathways. The results of Pearson correlation analysis indicated that differential protein expressions had a certain temporal relationship with the change of liver pathological degree. The above results indicated that the severity of liver damage caused by Gardeniae Fructus extract did not increase with time and would recover after drug with drawal. The above pathways may be related to the mechanism of liver injury induced by Gardeniae Fructus extract.

Combined application of extended depth of field imaging, image stitching and polarized microscopy techniques in identification of Spatholobus suberectus.

Objective: As traditional techniques for microscopic identification of Chinese medicines currently lack objective and high-quality reference images, here we developed a systemic procedure to be used in microscopic identification of Chinese medicines, which would lead to more objective, effective and accurate identification process. Methods: Spatholobi Caulis (Jixueteng in Chinese) was used as the specimen in the development of such procedure. Jixueteng samples were microscopically examined in bright- and dark-field microscopy. Microscopic images were obtained by regular, EDF, and image stitching techniques. Results: The microscopic images of the characteristics in pulverized Jixueteng were captured, thanks to EDF imaging and image stitching techniques which allowed the detailed and full sighting of each characteristic to be obtained simultaneously. Different layers in anatomical transverse section, including cork, phelloderm, cortex, phloem, cambium, xylem and pith, were distinctively observed. Moreover, by comparing images of bright- and dark-field microscopy, birefringent and non- birefringent components could readily be distinguished. Conclusion: With application of the developed procedure, high-definition, panoramic and microscopic images were acquired, which could be used as the reference images for microscopic identification of Chinese medicines.