This study aims to explore the protective effects of Picroside III, an active ingredient of Picrorhiza scrophulariiflora, on the intestinal epithelial barrier in tumor necrosis factor‐α (TNF‐α) induced Caco‐2 cells and dextran sulfate sodium (DSS) induced colitis in mice. Results show that Picroside III significantly alleviated clinical signs of colitis including body weight loss, disease activity index increase, colon shortening, and colon tissue damage. It also increased claudin‐3, ZO‐1 and occludin expressions and decreased claudin‐2 expression in the colon tissues of mice with colitis. In vitro, Picroside III also significantly promoted wound healing, decreased the permeability of cell monolayer, upregulated the expressions of claudin‐3, ZO‐1 and occludin and downregulated the expression of claudin‐2 in TNF‐α treated Caco‐2 cells. Mechanism studies show that Picroside III significantly promoted AMP‐activated protein kinase (AMPK) phosphorylation in vitro and in vivo, and blockade with AMPK could significantly attenuate the upregulation of Picroside III in ZO‐1 and occludin expressions and the downregulation of claudin‐2 expression in TNF‐α treated Caco‐2 cells. In conclusion, this study demonstrates that Picroside III attenuated DSS‐induced colitis by promoting colonic mucosal wound healing and epithelial barrier function recovery via the activation of AMPK.

Restoring the tumor-killing function of CD8+ T cells in the tumor microenvironment is an important strategy for cancer immunotherapy. Our previous study indicated that adiponectin (APN) deficiency reprogramed tumor-associated macrophages into an M1-like phenotype to inhibit rhabdomyosarcoma growth. However, whether APN can directly regulate the anti-tumor activity of CD8+ T cells remains unknown. In the present study, our results showed that exogenous APN inhibited in vitro CD8+ T cell migration as well as cytokines IFN-γ and TNF-α production. APN deficiency in vivo strengthened CD8+ T cell activation and cytotoxicity to restrain rhabdomyosarcoma, evidenced by an increase in the expression of IFN-γ and perforin in CD8+ T cells and the frequency of CD8+IFN-γ+ T cells in the spleen and lymph nodes, as well as increasing cytokine production of IFN-γ, perforin, TNF-α, and decreasing cytokine production of IL-10 in the serum. Mechanistically, STAT3 was identified as a target of APN in negatively regulating the anti-tumor activity of CD8+ T cells. In vivo, a STAT3 inhibitor remarkably increased CD8+ as well as CD8+IFN-γ+ T cells in the spleen and lymph nodes. Taken together, we substantiated that APN deficiency directly maintains the activation of CD8+ T cells to inhibit rhabdomyosarcoma growth by suppressing STAT3 activation, indicating a promising APN-based therapy for the treatment of rhabdomyosarcoma.

Purpose To explore the potential mechanism of glycosidic fraction of Picrorhiza scrophulariiflora Pennell (GPS) extract for the treatment of colitis using UPLC-QTOF-MS analysis, network pharmacology and experimental research. Methods The active components of GPS extract were identified by UPLC-QTOF-MS analysis and extracted their targets from the databases, which was used for network pharmacology analysis. Kyoto Encyclopedia of genes and genomes (KEGG) pathway analysis was performed to discover potential therapeutic mechanisms, and the network pharmacology results were then validated by in vivo and in vitro experiments. Results The results showed that GPS extract significantly alleviated the clinical signs of colitis, including body weight, disease activity index, colon shortening, and colon tissue damage, and inhibited the transcription and production of colonic IL-1β and IL-6 in DSS-induced colitis mice. In vitro, GPS extract also significantly suppressed nitric oxide (NO) production, iNOS expression, IL-1β and IL-6 transcription of LPS-activated RAW 264.7 cells. Network pharmacology integrated with experimental validation identified that GPS extract significantly suppressed Akt, p38, ERK, and JNK phosphorylation in vivo and in vitro, and luteolin, apocynin, caffeic acid, caffeic acid methyl ester, luteoloside, picroside II, aucubin, cinnamic acid, vanillic acid, and sweroside were the main components responsible for the anti-inflammatory effect of GPS. These findings demonstrate that the potential anti-inflammatory effect of GPS extract against colitis is achieved through suppressing PI3K/Akt and MAPK pathways, and that the abovementioned active components mainly exerted its anti-inflammatory effect. Conclusion The therapeutic effect of GPS extract on colitis is related to PI3K/Akt and MAPK pathways, which is a promising remedy for colitis therapy.