Dryness-alleviating effect of processed Aurantii Fructus from Lingnan based on correlation of fecal metabolomics and dryness / 中国中药杂志

With the approach of untargeted metabolomics and correlation analysis, this study aimed to explore the mechanism of Aurantii Fructus from Lingnan region in alleviating dryness by analyzing the different effects of raw Aurantii Fructus(RAF) and processed Aurantii Fructus(PAF) on fecal endogenous metabolism in normal rats. Eighteen Sprague-Dawley(SD) rats were randomly divided into a control group(C), an RAF group(10 g·kg~(-1)), and a PAF group(10 g·kg~(-1)). After seven days of administration, the effects of RAF and PAF on dryness-related indexes were compared, including water intake, fecal water content, salivary secretion, the expression of AQP5, VIP, and 5-HT in the submandibular gland, as well as the expression of AQP3, VIP, and 5-HT in the colon. The fecal samples in each group were determined by LC-MS. Multivariate statistical analysis and Pearson correlation coefficient were used for screening the differential metabolites and metabolic pathways in alleviating dryness of RAF. The results indicated that both RAF and PAF showed certain dryness, and the dryness of RAF was more significant. Moreover, PAF could alleviate dryness of RAF to a certain extent by reducing the water intake, fecal water content, and the expression of AQP3, VIP, and 5-HT in the colon and increasing the salivary secretion and the levels of AQP5, VIP, and 5-HT in the submandibular gland. According to the analysis of fecal metabolomics, 99 and 58 metabolites related to dryness were found in RAF and PAF respectively, where 16 of them played an important role in alleviating dryness of RAF. Pathway analysis revealed that the mechanism of PAF in alleviating dryness of RAF was presumably related to the regulation of riboflavin metabolism, purine metabolism, arginine biosynthesis, pyrimidine metabolism, alanine metabolism, aspartate metabolism, glutamate metabolism, and retinol metabolism pathways. This study suggested that PAF might alleviate dryness of RAF by affecting the metabolic levels of the body, which provides a new basis for further clarifying the processing mechanism of PAF.

Determining the protective effects of Ma-Mu-Ran Antidiarrheal Capsules against acute DSS-induced enteritis using 16S rRNA gene sequencing and fecal metabolomics / 中国天然药物

Ma-Mu-Ran Antidiarrheal Capsules (MMRAC) is traditional Chinese medicine that has been used to treat diarrhea caused by acute enteritis (AE) and bacillary dysentery in Xinjiang (China) for many years. However, the potential therapeutic mechanism of MMRAC for AE and its regulatory mechanism on host metabolism is unclear. This study used fecal metabolomics profiling with GC/MS and 16S rRNA gene sequencing analysis to explore the potential regulatory mechanisms of MMRAC on a dextran sulfate sodium salt (DSS)-induced mouse model of AE. Fecal metabolomics-based analyses were performed to detect the differentially expressed metabolites and metabolic pathways. The 16S rRNA gene sequencing analysis was used to assess the altered gut microbes at the genus level and for functional prediction. Moreover, Pearson correlation analysis was used to integrate differentially expressed metabolites and altered bacterial genera. The results revealed that six intestinal bacteria and seven metabolites mediated metabolic disorders (i.e., metabolism of amino acid, carbohydrate, cofactors and vitamins, and lipid) in AE mice. Besides, ten altered microbes mediated the differential expression of eight metabolites and regulated these metabolisms after MMRAC administration. Overall, these findings demonstrate that AE is associated with metabolic disorders and microbial dysbiosis. Further, we present that MMRAC exerts protective effects against AE by improving host metabolism through the intestinal flora.

Effect of Kansui Radix stir-fried with vinegar on fecal metabolomics in Walker-256 rats with ascites / 中国中药杂志

Utilizing metabolomics technology, this study explored the change of fecal endogenous metabolites in Walker-256 rats with malignant ascites after the administration with Kansui Radix(KR) stir-fried with vinegar(VKR), sought the potential biomarkers in feces which were related to the treatment of malignant ascites by VKR and revealed the biological mechanism of water-expelling effect of VKR. Ultra-fast liquid chromatography-quadrupole-time-of-flight mass spectrometry(UFLC-Q-TOF-MS) was employed to detect the feces of rats in all groups. Principle component analysis(PCA) and partial least squares discriminant analysis(PLS-DA) were conducted to achieve pattern recognition. Combining t-test and variable importance in the projection(VIP) enabled the screening of potential biomarkers for the malignant ascites. Metabolic pathway analysis was accomplished with MetaboAnalyst. Correlation analysis was finally conducted integrating the sequencing data of gut microbiota to elucidate the mechanism underlying the water-expelling effect of VKR. The results showed that both KR and VKR could restore the abnormal metabolism of model rats to some extent, with VKR being inferior to KR in the regulation. Eleven potential biomarkers were identified to be correlated with the malignant ascites and five metabolic pathways were then enriched. Four kinds of gut microbiota were significantly related to the potential biomarkers. The water-expelling effect of VKR may be associated with the regulation of phenylalanine metabolism, biosynthesis of phenylalanine, tyrosine and tryptophan, tryptophan metabolism, glycerophospholipid metabolism, and glycosylphosphatidylinositol(GPI)-anchor biosynthesis. This study can provide a scientific basis for comprehensive understandings of the interaction between gut microbiota and host which has relation to the water-expelling effect of VKR and guide the reasonable clinical application of VKR.

Study on the fecal metabolomics of CUMS-susceptible and CUMS-resilient rats / 药学学报

Proton nuclear magnetic resonance (1H NMR) based metabolomics was applied to characterize the fecal metabolic profiles of chronic unpredictable mild stress (CUMS)-depression (CUMS-D) and CUMS-resilience (CUMS-R) rats. The fecal biomarkers and metabolic pathways involved in CUMS-D and CUMS-R were screened and identified, revealing the underlying mechanisms of two different responses of the body to the same stresses. Firstly, the classic depression model, i.e. CUMS, was constructed. According to the fecal metabolomics profiles, the model rats were divided into two groups, i.e. the CUMS-D group and the CUMS-R group. And then, the depression statuses of CUMS-D rats and CUMS-R rats were verified by their sucrose preference rates. Lastly, multivariate data analysis was applied to clarify the fecal biomarkers and corresponding metabolic pathways involving in CUMS-D and CUMS-R. The results show that compared with the control rats, the sucrose preference rates of CUMS-D rats were significantly reduced. By contrast, the sucrose preference rates of CUMS-R rats had no significant difference. At the same time, CUMS-D and CUMS-R showed both unique and shared biomarkers and pathways. Three pathways are significantly related to CUMS-D, including taurine and hypotaurine metabolism, alanine, aspartate and glutamate metabolism, and arginine and proline metabolism. Glycerolipid metabolism and tryptophan metabolism are specific pathways related to CUMS-R. This study explores the mechanisms of the emergence of susceptible and resilience of rats under the same stimulus from a metabolomics perspective. The current findings provide not only a new perspective for studying depression, and personalized and precision treatments in clinic, but also the research and development of antidepressants.

Anti-depression mechanisms of Xiaoyao Powder based on fecal metabolomics / 中草药

Objective: To characterize the endogenous metabolites and metabolic changes of feces of chronic unpredictable mild stress (CUMS) rats by 1H-NMR, evaluate the improvement effects of Xiaoyao Powder and investigate the underlying mechanisms. Methods: The depression model was established by CUMS procedure. 1H-NMR coupled with multivariate statistical analysis was employed to reveal the changes of fecal metabolic profiles of CUMS rats and identify potential bio-markers involved in CUMS-induced depression. Based on the potential bio-markers, the relevant metabolic pathways were constructed. Results: A total of 10 metabolites was identified as potential bio-markers in fecal samples for the CUMS model. Compared with the control group, the contents of asparagine, aspartate, lactate and propionic acid in the CUMS rats were significantly increased (P < 0.05, 0.01), while phenylalanine, tyrosine, glutamate, glutamine, alanine and proline were significantly decreased (P < 0.05, 0.01). The administration of Xiaoyao Powder could significantly increase the levels of phenylalanine, tyrosine, glutamate, glutamine and proline, whereas reduced the levels of asparagine, lactate and propionic acid. Compared with the control group, six metabolic pathways were recognized as the most influenced pathways associated with the CUMS-induced depression: (1) aminoacyl-tRNA biosynthesis, (2) alanine, aspartate and glutamate metabolism, (3) arginine and proline metabolism, (4) glutamine and glutamate metabolism, (5) phenylalanine metabolism and (6) pyruvate metabolism. Among them, Xiaoyao Powder significantly mediated abnormalities of five pathways of (2), (3), (4), (5) and (6). Conclusion: It is the first report to investigate the antidepressant-like effects and underlying mechanisms of Xiaoyao Powder from the perspective of fecal metabolites. The current results showed that the anti-depression mechanisms of Xiaoyao Powder might be related to regulating the amino acid metabolism, glucose metabolism and intestinal microbial metabolism. This study provides a solid basis for revealing the anti-depression mechanisms of Xiaoyao Powder comprehensively and deeply.

Effect of chemical ingredients B and C in Kansui stir-baked with vinegar on fecal metabolomics in rats / 中国中药杂志

To reveal the toxic mechanism of Kansui stir-baked with vinegar(VEK), conducta comparative study on the metabolites of fecal samples of rats before and after being treated with chemical constituents group B and C(VEKB/VEKC) extracted from VEK by metabolomics approach. The fecal samples of each group were analyzed using ultra performance liquid chromatography-quadrupole-time of flight-mass spectrometry(UFLC-Q-TOF-MS). Then the data was processed by principal component analysis(PCA) and partial least square discriminant analysis(OPLS-DA) to screen and identify biomarkers relating to the toxicity of VEK. Besides, t-test was adopted for univariate statistical analysis, so as to study the changes of these biomarkers in drug groups before and after being treated with VEKB/VEKC and explore the effect of VEKB/VEKC on the metabolism of rat feces. Furthermore, the toxic mechanism of VEKB/VEKC was explored based on the results of the metabolic pathway analysis. The results displayed that compared with control group, the metabolism of fecal samples of VEKB and VEKC treated groups show obvious changes, and the VEKB treated group show more significant changes. A total of 16 potential biomarkers and 5 metabolic pathways relating to the toxicity of VEK were found and identified. And the toxicity of VEK might be associated with the disorder of such metabolic pathways as tryptophan metabolism, primary bile acid biosynthesis, amino sugar and nucleotide sugar metabolism, purine metabolism, and degradation of valine, leucine and isoleucine. This study provides a scientific basis for the clinical safety application of VEK.