Shaoyao Gancao

Shaoyao Gancao Decoction(SGD) is a classic formula used in the clinical treatment of joint diseases, such as rheumatoid arthritis(RA), though its mechanism of action remains unclear. This study aimed to explore the mechanism of SGD in treating RA through chemical and network pharmacology analyses, combined with cellular experiments. UPLC-Orbitrap-MS~2 was used to qualitatively analyze SGD and drug-containing serum of rats after oral administration of SGD, thereby identifying the chemical composition and plasma components of SGD. Potential targets for the plasma components in treating RA were identified using the SwissTargetPrediction, PharmMapper, GeneCards, and DrugBank databases, and a protein-protein interaction(PPI) network was constructed using the STRING data platform. GO functional enrichment and KEGG pathway enrichment analyses were conducted using the Metascape database. Molecular docking and lipopolysaccharide(LPS)-induced RAW264.7 cell experiments were utilized for in vitro validation. The results identified 95 compounds in SGD, including 15 prototypical absorbed components, i.e., 7 flavonoids, 5 terpenoids, 2 phenolic compounds, and 1 other compound. Network pharmacology analysis revealed that licoisoflavanone, liquiritin apioside, 5-hydroxyferulic acid, albiflorin, hederagenin, and paeoniflorin were the pharmacodynamic components of SGD for treating RA. The core targets of SGD for RA treatment were identified as SRC, MAPK, EGFR, HSP90AA1, and STAT3, with regulation of the NF-κB, PI3K-Akt, and MAPK signaling pathways identified as key mechanisms for anti-RA effects of SGD. Molecular docking results showed that the six core components exhibited high affinity with the key targets SRC, MAPK, and NF-κB. In vitro cellular experiments demonstrated that SGD down-regulated the expression of inflammatory factors, including interleukin-1β(IL-1β), cyclooxygenase-2(COX-2), and tumor necrosis factor-α(TNF-α), in LPS-induced RAW264.7 cells. Western blot analysis revealed that SGD significantly reduced the phosphorylation levels of NF-κB p65 and p38 MAPK proteins. This study provides a scientific basis for further research into the active components and mechanisms of action of SGD in treating RA.

To study the therapeutic effect and mechanism of Shaoyao Gancao Decoction (SGD) on ulcerative colitis (UC) mice based on the perspective of intestinal barrier, and this study provides a new consultation for the clinical application of SGD.

The chemical composition of SGD was characterized by HPLC. The UC mouse model was constructed by 3 % dextran sodium sulfate (DSS), which were randomly divided into the model group (DSS), the positive drug group (5-ASA), the Shaoyao group (SYD), Gancao group (GCD), and the Shaoyao Gancao Decoction group (SGD) at low, medium, and high dosages, respectively. The effects of each drug treatment group on UC were evaluated by the rate of body weight loss, disease activity index (DAI), colon length, spleen index, histopathological evaluations, and the levels of serum inflammatory factors (IL-1β, IL-6, IL-10, IL-21, and TNF-α). The goblet cell was observed by Alcian blue/periodic acid-Schiff (AB/PAS) straining, ELISA was used to detect the content of LPS in serum, and Western blot was used to detect the changes in the expression of tight junction proteins ZO-1, occludin, and the pathway proteins TLR4 and NF-κBp65 in the colonic tissues, to explore the protective effect of SGD on the intestinal barrier of UC mice. The vivo absorption process of the main active ingredients in the SG, SY and GC groups was determined by LC-MS.

The contents of albiflorin, paeoniflorin, liquiritin apioside, liquiritin and glycyrrhetinic acid were 6.1227 mg/g, 20.8993 mg/g, 4.0054 mg/g, 3.6140 mg/g and 8.2515 mg/g, respectively. Compared with DSS group, SGD reduced weight loss(P<0.01) and DAI scores(P<0.05), prevented colon shortening(P<0.01), and ameliorated histopathological damage of the colon in UC mice(P<0.01). SGD also protected the intestinal barrier to alleviate UC by significantly reducing serum LPS and inflammatory factor levels, altering the number of goblet cells, promoting tight junction proteins (ZO-1 and occludin) and decreasing the expression of TLR4 and NF-κB in colonic tissues. Pharmacokinetic results showed that there was no significant difference in C_max, AUC_{0-t (μg/L}._h) and T_max of albiflorin and paeoniflorin between the SY and SG groups, the T_max was within 1 h; the AUC_{0-t (μg/L}._h) of liquiritin and glycyrrhizic acid were about 1.6 and 1.9 times higher in the SG group compared to the GC group, respectively. The C_max, T_max and AUC_{0-t (μg/L}._h) of glycyrrhizinic acid were significantly reduced to 0.73, 0.68 and 0.68 times of that of the GC group.

SGD may have a therapeutic effect on DSS-induced UC mice by repairing the damaged intestinal barrier through the TLR4/NF-κB pathway. The combination of Shaoyao and Gancao increased the absorption of liquiritin and glycyrrhizic acid in vivo. The combination of Shaoyao and Gancao could promote the absorption of Gancao, and that the pairing of the two herbs could have a synergistic effect.