Sijunzi Decoction

As a classical traditional Chinese medicine formula to invigorating spleen and replenishing qi, Sijunzi decoction (SJZD) is composed of four herbs, which is applied to cure spleen deficiency syndrome (SDS) clinically. The non-polysaccharides (NPSs) of SJZD (SJZD_NPS) are important pharmacodynamic material basis. However, the amelioration mechanism of SJZD_NPS on SDS has not been fully elaborated. Additionally, the contribution of herbs compatibility to efficacy of this formula remains unclear.

The aim was to explore the underlying mechanisms of SJZD_NPS on improving SDS, and uncover the scientific connotation in SJZD compatibility.

A strategy integrating incomplete formulae (called "Chai-fang" in Chinese) comparison, pharmacodynamics, gut microbiome, and metabolome was employed to reveal the role of each herb to SJZD compatibility against SDS. Additionally, the underlying mechanism harbored by SJZD_NPS was further explored through targeted metabolomics, network pharmacology, molecular docking, pseudo-sterile model, and metagenomics.

SJZD_NPS significantly alleviated diarrhea, disordered secretion of gastrointestinal hormones and neurotransmitters, damage of ileal morphology and intestinal barrier in SDS rats, which was superior to the NPSs of Chai-fang. 16S rRNA gene sequencing and metabolomics analyses revealed that SJZD_NPS effectively restored the disturbed gut microbiota community and abnormal metabolism caused by SDS, showing the most evident recovery. Moreover, SJZD_NPS recalled the levels of partial amino acids, short chain fatty acids and bile acids, which possessed strong binding affinity towards potential targets. The depletion of gut microbiota confirmed that the SDS-amelioration efficacy of SJZD_NPS is dependent on the intact gut microbiome, with the relative abundance of potential probiotics such as Lactobacillus_johnsonii and Lactobacillus_taiwanensis been enriched.

NPSs in SJZD can improve SDS-induced gastrointestinal-nervous system dysfunction through regulating microbiota-gut-metabolites axis, with four herbs exerting synergistic effects, which indicated the compatibility rationality of SJZD.

Mitomycin C (MMC) has an antitumor effect and is considered as a broad‐spectrum antibiotic. Sijunzi Decoction (SJZD), a well‐known ancient Chinese prescription, is widely used in the treatment of cancer when combined with chemotherapy drugs. Studies have shown that SJZD can be combined with other drugs to enhance the therapeutic effect against cancer and inhibit the toxicity of chemotherapy drugs, but the specific mechanism is not clear. Thus, we hope to further explore the antitumor mechanism of combined SJZD and MMC. 3‐(4,5‐Dimethyl‐2‐thiazolyl)‐2, 5‐diphenyl‐2‐H‐tetrazolium bromide assay, flow cytometry, western blot, 1H NMR and HPLC–MS were used to study the mechanism at the cellular level. The results show that the combined administration can have a more significant effect on inhibiting the proliferation of cancer cells, promoting their apoptosis. Based on metabolomics, 38 biomarkers were found in the MMC group and 43 biomarkers were found in the combined administration group. Among them, 18 unique biomarkers were discovered in the combined administration group. Studies have shown that the antitumor mechanism of combined administration is related to amino acid metabolism, energy metabolism, lipid metabolism and nucleotide metabolism, among which amino acid metabolism is the most important. In addition, SJZD achieves the effect of toxin reduction and efficiency enhancement by improving the body's immunity and improving the oxidative stress environment.