"Correspondence between prescription and syndrome" is the foundation of the objectification of traditional Chinese medicine diagnosis and treatment， and the objectification of traditional Chinese medicine diagnosis is the key to the modernization of traditional Chinese medicine. Combining modern theories and technological means to explore objective indicators or biomarkers of "correspondence between prescription and syndrome" can help clarify quantitative indicators of syndromes. There is a characteristic microbial population in the intestine that is related to syndromes and prescription efficacy. Intestinal microbiota plays an important indicative and discriminative role in determining the formation and evolution of disease patterns and is also an important characterization and pathway of the therapeutic effect of prescriptions. Therefore， intestinal microbiota can serve as an important biological indicator for the objectification of "correspondence between prescription and syndrome"， and the research content related to "intestinal microbiota-syndrome" and "intestinal microbiota-prescription" is relatively mature. On this basis， the team proposed a research approach and method of "correspondence among intestinal microbiota， syndrome， and prescription"， exploring the biological mechanism of "correspondence between prescription and syndrome" from the perspective of intestinal microbiota. A complete analysis of the "intestinal microbiota-syndrome-prescription" data content of six traditional Chinese medicine diarrhea syndromes was conducted， and the results of intestinal dominant and characteristic microbiota for different syndromes of diarrhea and corresponding formula interventions were obtained. The correlation of key intestinal microbiota and metabolites with the interaction between different syndromes and formula interventions was studied， and the microbiological mechanism of "treating the same disease with different methods" for diarrhea was explored. The research ideas and results provide the possibility for the establishment and application of the theory of "correspondence among intestinal microbiota， syndrome， and prescription" and also provide a research paradigm for other diseases in traditional Chinese medicine. "Correspondence among intestinal microbiota， syndrome， and prescription" is conducive to revealing the micro-mechanisms of the formation and evolution of traditional Chinese medicine syndromes and the efficacy of prescriptions. It establishes an objective diagnosis and treatment system for traditional Chinese medicine syndromes based on intestinal microbiota， providing new methods and ideas for the objective diagnosis and treatment of traditional Chinese medicine syndromes and promoting the modernization and internationalization of traditional Chinese medicine.

ObjectiveTo investigate the effects of Xijiao Dihuangtang （XJDHT） on mice with sepsis and cellular models of sepsis and explore its molecular mechanism in alleviating sepsis-induced inflammatory responses via regulating pyruvate kinase M2 （PKM2）-mediated one-carbon metabolism pathway. MethodsForty C57BL/6N mice were randomly divided into four groups： normal group， model group， low-dose XJDHT group （7.7 g·kg^-1）， and high-dose XJDHT group （15.4 g·kg^-1）. After one week of continuous gavage， sepsis was induced using cecal ligation and puncture （CLP） in groups except the normal group. 24 h after the surgery， mortality rates in all groups were recorded， and serum cytokines were measured by enzyme linked immunosorbent assay （ELISA）. Lung histopathology was examined by hematoxylin-eosin （HE） staining. During the in vitro experiment， the human monocytic leukemia cell line （THP-1） was exposed to various concentrations of XJDHT and treated with lipopolysaccharide （LPS） at a final concentration of 2 mg·L^-1 for 24 h. Cell apoptosis was detected using terminal deoxynucleotidyl transferase dUTP nick end labeling （TUNEL） assay. Protein levels of tumor necrosis factor-α （TNF-α）， interleukin-1β （IL-1β）， B-cell lymphoma 2 （Bcl-2）， and Bcl-2-associated X protein （Bax） were measured by Western blot. Transcriptome sequencing was performed to analyze differentially expressed genes in all groups and conduct gene ontology （GO） enrichment. Key genes in the one-carbon metabolism pathway， including pyruvate kinase M2 （PKM2）， 5-methyltetrahydrofolate-homocysteine methyltransferase （MTR）， and phosphoglycerate dehydrogenase （PHGDH）， were verified by Western blot. A PKM2 inhibition model was established using shikonin for further protein expression analysis. ResultsAnimal experiments showed that compared with the normal group， the model group exhibited significantly elevated body temperature and lung pathology （P<0.01） and increased serum TNF-α and IL-1β levels （P<0.01）. High-dose XJDHT reduced body temperature and lung tissue damage （P<0.01） and significantly decreased serum TNF-α and IL-1β levels （P<0.01）. Low-dose XJDHT treatment showed no significant temperature change （P<0.01） but reduced serum TNF-α and IL-1β levels （P<0.01）. Transcriptome sequencing and Western blot revealed significant differences in the expression of TNF-α， IL-1β， and one-carbon metabolism genes （PKM2， MTR， and PHGDH） （P<0.01）. Cell experiments demonstrated that compared to the normal group， the model group showed elevated protein expressions of TNF-α and IL-1β in THP-1 cells （P<0.01）， decreased Bcl-2/Bax ratio， and increased apoptosis （P<0.01）. Transcriptome sequencing and Western blot revealed significant differences in the expression of TNF-α， IL-1β， and one-carbon metabolism genes （PKM2， MTR， and PHGDH） （P<0.01）. Compared to the model group， high-dose XJDHT significantly increased Bax/Bcl-2 ratio and PHGDH protein expression （P<0.01） and effectively reduced cell apoptosis （P<0.01） while down-regulating protein expressions of TNF-α， IL-1β， PKM2， and MTR （P<0.01）. Low-dose XJDHT moderately increased Bax/Bcl-2 ratio and PHGDH protein expression （P<0.05）， reduced apoptosis （P<0.05）， and decreased IL-1β and MTR protein levels （P<0.05， P<0.01）， but there were no significant changes in TNF-α and PKM2 expression. After PKM2 inhibition by shikonin in THP-1 cells， the expression of protein related to one-carbon metabolism was detected. Compared with the blank group， the LPS-induced model group showed significantly upregulated PKM2 and MTR protein expression （P<0.01） and downregulated PHGDH expression （P<0.01）. Compared with the model group， shikonin treatment significantly reduced PKM2 expression （P<0.05）， increased PHGDH expression （P<0.01）， and decreased MTR expression （P<0.05）. ConclusionXJDHT can inhibit the release of inflammatory factors in sepsis， and its mechanism is related to the intervention of the PKM2-regulated one-carbon metabolism pathway in macrophages.