Integrating plasma metabolomics and gut microbiome to reveal the mechanisms of Huangqi Guizhi Wuwu Decoction intervene diabetic peripheral neuropathy.

ETHNOPHARMACOLOGICAL RELEVANCE: Huangqi Guizhi Wuwu Decoction (HGWD) is a classic traditional Chinese herbal formula from "Synopsis of Golden Chamber," which is used to treat blood stagnation and has been used for alleviating diabetic peripheral neuropathy (DPN) in the clinic. However, the mechanisms of HGWD intervention DPN are still to be discovered. AIM OF THE STUDY: This study aims to explore the mechanism of HGWD intervention DPN by integrating plasma metabolomics and gut microbiome. MATERIALS AND METHODS: BKS Cg-m+/+Leprdb/J (db/db) mice with DPN were at 16 weeks of age. The indices of DPN phenotypes in db/db mice, pathomorphology of the sciatic nerve, intraepithelial nerve fibers (IENF) of the foot pad, levels of blood lipids and oxidative stress, and inflammatory reaction were used to appraise the HGWD efficacy. Finally, the pharmacological mechanisms of HGWD intervening DPN were explored by metabolomics and 16S rRNA gene sequencing. RESULTS: HGWD reversed DPN phenotypes in db/db mice, improved peripheral nerve structure, ameliorated the level of blood lipids and nerve growth factor in plasma, enhanced antioxidant capacity, and alleviated inflammatory responses. Plasma metabolomics disclosed that HGWD remarkably regulated the unusual levels of thirty-seven metabolites involved in sphingolipid metabolism, biosynthesis of unsaturated fatty acids, arachidonic acid metabolism, and amino acid biosynthesis pathways. The gut microbiome showed that nine bacteria were highly correlated with the efficacy of HGWD in DPN. Integrating analysis of microbiome and metabolomics demonstrated that the interaction of four bacteria with four metabolic pathways might be the significant mechanism of HGWD intervention in DPN. CONCLUSIONS: The mediation of gut microbiota and plasma metabolism may be the potential mechanism of HGWD ameliorating DPN in db/db mice. The interaction of Lactobacillus, Alloprevotella, Bacteroides, and Desulfovibio with four metabolic pathways might be the critical mechanism for HGWD treating DPN.

[Simultaneous determination of seven nucleosides and nucleobases in aqueous extracts of Fritillaria taipaiensis by HPLC-DAD].

OBJECTIVE: To develop a high performance liquid chromatography coupled with a photodiode array detector (HPLC-DAD) method for simultaneous determination of 7 nucleosides and nucleobases in Fritillaria taipaiensis. METHOD: The analyses were performed on an Agilent Zorbax-SB-Aq-C18 column (4.6 mm x 250 mm, 5 microm) eluted with water and methanol in gradient mode. The flow rate was 1.0 mL x min(-1). The detection wavelength was 260 nm. The temperature of sample manager was set at 25 degrees C, and the injection volume was 20 microL. RESULT: The investigated compounds including uracil, cytidine, uridine, guanosine, thymidine, adenosine and adenine were shown good linearity (r > or = 0.999 8) over the tested ranges. The average recoveries were within 96.96% - 103.5% with RSD < or = 3.8%. CONCLUSION: The accuracy, stability, repeatability and average recovery of the method are satisfying, and the seven nucleosides and nucleobases components in F. taipaiensis can be rapidly and accurately quantified by HPLC-DAD. This work provided helpful information for comprehensive quality evaluation of F. taipaiensis.