Gastrodia elata Blume was used to treat stroke and headaches caused by “Feng” for thousands of years. The present study has shown a significant effect of G. elata Blume in improving cerebral ischemia–reperfusion injury (CIRI). However, the mechanism of G. elata Blume in improving CIRI by regulating the intestinal flora has not been reported until now. This research aimed to comprehensively evaluate the mechanism of G. elata Blume in CIRI based on fecal metabolomics and 16S rDNA sequencing. The rat model with CIRI was created based on the Zea Longa method. Enzyme-linked immunosorbent assay (ELISA) was used to monitor the inflammatory factors in rat serum. Damages of brain tissues were observed using hematoxylin and eosin (H&E) staining. Cerebral infarction was observed by 2,3,5-triphenyltetrazolium chloride (TTC) staining. The balance of intestinal flora in cecal contents of rats was evaluated by high-throughput sequencing. Changes of metabolites in the intestinal flora were evaluated by fecal metabolomics through Ultra high performance liquid chromatography-orbitrap exploris-mass spectrometer (UHPLC-OE-MS). The area of brain necrosis, cerebral infarction volume, and the contents of inflammatory factors in CIRI rats can be effectively reduced after oral administration of G. elata Blume. CIRI can cause disturbances in the intestinal flora and its associated metabolites. G. elata Blume can significantly regulate the composition of the intestinal microflora. It reversed CIRI-induced changes in the levels of multiple intestinal bacteria, including Prevotellaceae, Coriobacteriaceae; Prevotella, Gamma proteobacteria unclassified, Barnesiella, Escherichia, Shigella; uncultured Shigella sp., Flavonifractor sp., Escherichia sp. enrichment culture clone NBAR004, Veillonella sp. R-32, and Lactobacillus intestinalis. The levels of metabolites in cecal contents were disturbed in rats with CIRI, including amino acid, purine, and sphingolipid metabolism. The changes in the level of biomarkers in amino acid metabolism induced by CIRI were significantly reversed after treatment with G. elata Blume. Correlation studies show that Prevotellaceae was significantly positively correlated with interleukin (IL)-6, and L. intestinalis and L-phenylalanine were negatively interrelated to IL-1β. Beta-glycerophosphoric acid was significantly negatively interrelated to high-sensitivity C-reactive protein (hs-CRP). There were significantly negative correlations between L-phenylalanine and L. intestinalis, beta-glycerophosphoric acid and Prevotellaceae. G. elata Blume protected against CIRI, which may be related to improved intestinal microflora composition and metabolism, resulting in decreased inflammation.

Introduction: Semen Cuscutae is a traditional Chinese medicine (TCM) that tonifies the kidneys and prevents miscarriage. According to Chinese medicine theory, kidney deficiency is one of the main causes of recurrent spontaneous abortion (RSA). The previous studies showed that raw product of Semen Cuscutae (SP) and Semen Cuscutae processed with salt solution (YP) have ameliorative effects on RSA, and that YP is superior to SP. However, the active components of YP to ameliorate RSA remain unclear and require further studies. The objective of this study is to investigate the active components of YP in ameliorating RSA.Methods: First, a rat model of RSA was established using hydroxyurea in combination with mifepristone. Aqueous decoction of YP was given by gavage to rats. Second, pregnant rats were sampled on days 5, 7, 9, 10 and 12 during the modelling period. The content of Hyperin (HY), astragalin (AS) and kaempferol-3-O-β-D-glucuronide (KA) in blood and liver, heart, spleen, lung and kidney tissues were detected by liquid chromatography-mass spectrometry (LC-MS). The pharmacodynamic indicators including progesterone (P), chorionic gonadotropin β (β-HCG), estradiol (E2), tumor necrosis factor-α (TFN-α), interleukin 4 (IL-4), and tryptophan (TRP) were measured by enzyme-linked immunosorbent assay (ELISA) Pearson's correlation analysis and grey relational analysis were used to establish the relationship between the pharmacodynamic indexes and chemical constituents.Results: The pharmacokinetic results showed that the area under curve (AUC) value of KA was the largest. The tissue distribution results showed that astragalin was widely distributed in liver, heart, spleen, lung and kidney in the RSA model rats, while HY was detected only in the uterus, and KA was detected only in the kidney. The pearson correlationl analysis showed that KA was significantly and positively correlated with the contents of E2, P, β-HCG and TRP. Both AS and HY were significantly negatively correlated with the content of TNF-α, respectively.Discussion: This study reveals the pharmacokinetics and tissue distribution of KA, AS and HY in rats with RSA. It was elucidated that all three were involved in the regulation of progesterone levels and immune function. It initially revealed the mechanism of action of YP in enhancing the improvement of RSA, and it provided a theoretical basis for the quality assessment of YP.