Gut microbiota as a target for prevention and treatment of type 2 diabetes: Mechanisms and dietary natural products.

Type 2 diabetes mellitus (T2DM) is among the most remarkable public health concerns globally. Accumulating research evidence documents that alteration of gut microbiota has an indispensable role in the onset and progression of obesity and T2DM. A reduced microbial diversity is linked to insulin resistance and energy metabolism, especially for the rise of the Firmicutes/Bacteroidetes ratio. Changes in metabolites followed by the gut dysbacteriosis are linked to the presence of T2DM. Moreover, endotoxin leakage and gut permeability caused by gut dysbacteriosis is more of a trigger for the onset and progression of T2DM. Research documents that natural products are remarkable arsenals of bioactive agents for the discovery of anti-T2DM drugs. Many studies have elucidated that the possible mechanisms of the anti-T2DM effects of natural products are remarkably linked to its regulation on the composition of gut microflora and the successive changes in metabolites directly or indirectly. This review presents a brief overview of the gut microbiota in T2DM and several relevant mechanisms, including short-chain fatty acids, biosynthesis and metabolism of branched-chain fatty acids, trimethylamine N-oxide, bile acid signaling, endotoxin leakage, and gut permeability, and describes how dietary natural products can improve T2DM via the gut microbiota.

Discovery of Quality Markers in Hugan Qingzhi Formula by Integrating a Lipid-Lowering Bioassay with UHPLC-QQQ-MS/MS.

Nonalcoholic fatty liver disease (NAFLD) is a prevalent chronic liver disease. The Hugan Qingzhi formula (HGQZ) has been proven effective in treating NAFLD through clinical and pharmacological mechanism studies. A screening study of the chemical components was carried out to better control the quality of this formula. Current research has combined biological activity assessment with chemical analysis to screen and identify the bioactive compounds in HGQZ for use as potential quality markers (Q-markers) to control the quality of this herbal product. The HGQZ extracted by three different solvents was evaluated in a free fatty acid-induced hepatic steatosis LO2 cell model. Simultaneously, the twelve major chemical constituents of these extracts were quantitatively measured by ultrahigh-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UHPLC-QQQ-MS/MS). Extraction with 50% ethanol showed the most potent lipid-lowering effect in steatosis LO2 cells and the highest extraction rate of major chemical constituents. Correlation analysis was used to establish the relationship between the biological activities and chemical characteristics of these extracts. The results showed that the contents of typhaneoside, hyperoside, isoquercitrin, isorhamnetin-3-O-neohesperidoside, notoginsenoside R1, and alisol B 23-acetate were positively correlated to the lipid-lowering effect. The subsequent bioassay confirmed that typhaneoside, isoquercitrin, and alisol B 23-acetate played the role of reducing the lipid effect. In conclusion, 50% of ethanol extraction produced the most active extract of HGQZ. Typhaneoside, isoquercitrin, and alisol B 23-acetate could be considered potential Q-markers for the quality control of HGQZ.

[Effect of Hugan Qingzhi tablets on AMPK pathway activation and NF-κB-p65 protein expression in the liver of rats with nonalcoholic fatty liver disease].

OBJECTIVE: To investigate the effect of Hugan Qingzhi tablets on lipid metabolism and inflammation in rats fed on high-fat diet and explore the underlying mechanisms. METHODS: Sixty male Sprague-Dawley rats were randomly divided into 6 groups, namely HFD group (with high-fat diet and distilled water), control group (with normal diet and distilled water), fenofibrate group (with high-fat diet and treatment with 0.1 g

Comparison of microbial diversity determined with the same variable tag sequence extracted from two different PCR amplicons.

BACKGROUND: Deep sequencing of the variable region of 16S rRNA genes has become the predominant tool for studying microbial ecology. As sequencing datasets have accumulated, meta-analysis of sequences obtained with different variable 16S rRNA gene targets and by different sequencing methods has become an intriguing prospect that remains to be evaluated experimentally. RESULTS: We amplified a group of fecal samples using both V4F-V6R and V6F-V6R primer sets, excised the same V6 fragment from the two sets of Illumina sequencing data, and compared the resulting data in terms of the α-diversity, ß-diversity, and community structure. Principal component analysis (PCA) comparing the microbial community structures of different datasets, including those with simulated sequencing errors, was very reliable. Procrustes analysis showed a high degree of concordance between the different datasets for both abundance-weighted and binary Jaccard distances (P < 0.05), and a meta-analysis of individual datasets resulted in similar conclusions. The Shannon's diversity index was consistent as well, with comparable values obtained for the different datasets and for the meta-analysis of different datasets. In contrast, richness estimators (OTU and Chao) varied significantly, and the meta-analysis of richness estimators was also biased. The community structures of the two datasets were obviously different and led to significant changes in the biomarkers identified by the LEfSe statistical tool. CONCLUSIONS: Our results suggest that beta-diversity analysis and Shannon's diversity are relatively reliable for meta-analysis, while community structures and biomarkers are less consistent. These results should be useful for future meta-analyses of microbiomes from different data sources.

[The quality standard study on Hugan qingzhi tablets].

OBJECTIVE: To develop a method of quality control for Hugan qingzhi tablets. METHODS: Fructus Crataegi, Rhizoma Alismatis and Radix Notoginseng were identified by TLC. HPLC was used for the determination of ursolic acid in Hugan qingzhi tablets. RESULTS: The chromatographic spots were identified without the interference of negative control. Ursolic acid had a good linearity over the concentration range of 40-200 microg/mL (r = 1.000). The average recoveries was 99.05% with relatively standard deviations of 1.3%. CONCLUSION: This method is reliable, accurate and specific and can be used for the quality control of Hugan qingzhi tablets.

[Optimization of the supercritical fluid extraction process of Tuirezhitongsan].

OBJECTIVE: To optimize the extraction process of Tuirezhitongsan and extract the pharmacodynamically active fractions. METHODS: Orthogonal test methods and supercritical-CO(2) fluid extraction (SFE-CO(2)) were used for the extraction, and the the pharmacodynamically active fractions were screened with analgesic experiments. RESULTS: The optimal extraction of the active fractions was achieved with the extraction pressure at 25 MPa, extraction temperature at 45 degrees celsius, resolution pressure at 6.7 MPa, and resolution temperature at 50 degrees celsius. CONCLUSION: SFE- CO(2) is rapid, efficient, and energy-saving in the extraction of the active fractions in Tuirezhotongsan, and provides a mew method for extraction of traditional Chinese medicine.

[Study of the extraction technique of volatile oil from Chinese herbs for manufacturing Xiaoerjianpixiaoshi oral solution].

OBJECTIVE: To determine the optimal extracting technique for the volatile oil from the Chinese herbs for manufacturing Xiaoerjianpixiaoshi oral solution. METHODS: Two steam distillation processes were carried out to extract the volatile oil from three Chinese herbs. UV-spectrophotometry method was used to determine the oil content in the distillate, and the mathematical model was established according to volatile oil distillation process by exponential curve regression analysis. RESULT: Direct extraction of the oil by means of steam distillation process was more workable, and the decrement of oil content conformed well with the exponential model. Collection of 2 volumes of the distillate resulted in the yield of volatile oil of 61.64%. CONCLUSION: The optimal extraction of the volatile oil can be resulted from immersion of the drugs in 8 volumes of water for 0.5 h and collection of 2 volumes of the distillate.

Analysis with gas chromatography and mass spectrography of volatile components of Ligusticum wallichii Franch extracted by CO2 supercritical fluid extraction in combination with molecular distillation.

OBJECTIVE: To evaluate the possibility of using the technique of CO2 supercritical fluid extraction (SFE) combined with molecular distillation (MD) to extract, separate and purify the volatile components of Ligusticum wallichii Franch, a Chinese herbal medicine. METHODS: SFE was employed to extract the volatile components of Ligusticum wallichii Franch, followed by MD of the product. Analysis of the chemical constituents of the extract both before and after MD was performed with gas chromatography (GC) in conjunction with mass spectrography (MS). RESULTS: There were 45 kinds of chemical constituents in the extract of Ligusticum wallichii Franch yielded from SFE, among which 39 were left after distillation by MD. Changes also took place in the content of the constituents in the extract after distillation. CONCLUSIONS: SFE combined with MD, a technique better than simple SFE, can be used to extract, separate and purify the volatile components of Chinese herbs.

Determination of L-sesamin and L-asarinin in Zanthoxylum(Roxb.) DC. by high performance liquid chromatography.

OBJECTIVE: To establish a method for determining the content of L-sesamin and L-asarinin indifferent parts of Zanthoxylum(Roxb.)DC. METHOD: High-performance liquid chromatography (HPLC) was utilized for this purpose with the column of HYPERSIL BDS C18 and the mobile phase containing acetonitrile and water (50:50), the detection wavelength being 287 nm. RESULTS: The average recovery rates for L-sesamin and L-asarinin were 100.13% and 1.61% and their relative standard deviation (RSD) were 101.24% and 1.46% respectively. CONCLUSION: The method can be used for the quality control of Zanthoxylum(Roxb.)DC, and the roots of this herb contains more L-sesamin and L-asarinin than its other parts do.