An integrated network analysis, RNA-seq and in vivo validation approaches to explore the protective mechanism of Mongolian medicine formulae Ruda-6 against indomethacin-induced gastric ulcer in rats.

Gastric ulcer (GU) is one of the most prevalent digestive diseases that seriously affects people's health. Previous studies have demonstrated the anti-GU effect of Ruda-6 (RD-6), a classic formulae of traditional Mongolian medicine. However, the underlying mechanism of RD-6 against GU remains elusive. Thus, we conducted an integrative approach of network analysis, RNA-seq, and in vivo validation experiment to elucidate the therapeutic mechanisms of RD-6 in preventing GU. A network analysis was performed to predict the potential targets of RD-6. Rats were pretreated with RD-6 at different doses for 21 days, followed by GU induction with indomethacin injection. The ulcer index and inhibition rates were calculated, and the levels of inflammatory related factors were determined by ELISA. The gastroprotective mechanism of RD-6 against ulceration was verified by RNA-seq and the key pathway was detected by in vivo validation. As the network analysis predicted, RD-6 exerts anti-GU effects by regulating 75 targets and 160 signaling pathways. Animal experiment results suggested that pretreatment with RD-6 significantly ameliorated the gastric mucosal injury and inflammatory response, as evidenced by a reduced ulcer index, decreased interleukin (IL)-1ß, IL-6, and IL-17 levels, and increased prostaglandin E2 (PGE2) levels in the GU model rats induced by indomethacin. RNA-seq data identified four potential hub genes that were primarily involved in the IL-17 signaling pathway. Furthermore, in vivo validation experiment showed that RD-6 inhibited the IL-17 signaling pathway by down-regulating the expression of IL17RA, proto-oncogene C-Fos (FOS), IL1B and prostaglandin-endoperoxide synthase 2 (PTGS2). Taken together, the present study provides evidence that RD-6 could effectively protect against indomethacin-induced GU, which might be attributed to suppressed inflammation. The IL-17 signaling pathway may be one of the crucial mechanisms that mediates the effect of RD-6.

Mongolian medicine formulae Ruda-6 alleviates indomethacin-induced gastric ulcer by regulating gut microbiome and serum metabolomics in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Ruda-6 (RD-6), a typical traditional Mongolian medicine formulae consisting of 6 herbs, has been traditionally used in treating gastric disorders. Even though it has been shown to protect against gastric ulcers (GU) in animal models, the gut microbiome and serum metabololite-related mechanisms that prevent GU are not well understood. AIM OF THE STUDY: This study was conducted to evaluate the gastroprotective mechanism of RD-6 associated with the alteration of the gut microbiome and serum metabolic profiles in GU rats. MATERIALS AND METHODS: RD-6 (0.27, 1.35 and 2.7 g/kg) or ranitidine (40 mg/kg) were orally administered in rats for three weeks before the induction of gastric ulcer using indomethacin (30 mg/kg, single oral dose). The gastric ulcer index, ulcer area, H&E staining, and the levels of TNF-α, iNOS, MPO and MDA were quantified to evaluate the ulcer inhibitory effects of RD-6. Then, 16S rRNA gene sequencing combined with LC-MS metabolic profiling was performed to investigate the effect of RD-6 on the gut microbiota and serum metabolites in rats. Moreover, a spearman analysis was used to calculate the correlation coefficient between the different microbiota and the metabolites. RESULTS: RD-6 inhibited the gastric lesion damage caused by indomethacin in rats, decreased the ulcer index by 50.29% (p < 0.05), reduced the levels of TNF-α, iNOS, MDA and MPO in gastric tissue. Additionally, RD-6 reshaped the diversity and microbial composition, and reversed the reduced bacteria including [Eubacterium]_xylanophilum group, Sellimonas, Desulfovibrio, and UCG-009, and the increased bacteria Aquamicrobium caused by indomethacin induction. Furthermore, RD-6 regulated the levels of metabolites including amino acids and organic acids, and these affected metabolites were involved in taurine and hypotaurine metabolism and tryptophan metabolism. Spearman analysis revealed that the perturbed gut microbiota were closely related to the changes in differential serum metabolites. CONCLUSION: In view of the 16S rRNA gene sequencing and LC-MS metabolic results, the present study suggests the mechanism of RD-6 ameliorating GU via modulating intestinal microbiota and their metabolites.

Pharmacological Mechanism of Aucklandiae Radix against Gastric Ulcer Based on Network Pharmacology and In Vivo Experiment.

Background and Objectives: Aucklandiae Radix is a well-known medicinal herb that is often used to treat gastric ulcer, but its molecular mechanism of anti-ulcer action is poorly understood. This research aimed to reveal the potential active components, core targets, and mechanisms of Aucklandiae Radix in treating gastric ulcer by combining network pharmacology and animal experimentation. Materials and Methods: First, a network pharmacology strategy was used to predict the main components, candidate targets, and potential signaling pathways. Molecular docking was then used to confirm the binding affinity between the main components and primary targets. Finally, rats were treated with indomethacin 30 mg/kg to establish a gastric ulcer model. Aucklandiae Radix extract (0.15, 0.3, and 0.6 g/kg) was pre-treated in rats by oral gavage for 14 days, and the protective effect and candidate targets of network pharmacology were validated through morphological observation, pathological staining, and biochemical index detection. Results: A total of eight potential active components and 331 predicted targets were screened from Aucklandiae Radix, 37 of which were common targets with gastric ulcer. According to the component-target network and protein-protein interaction (PPI) network, stigmasterol, mairin, sitosterol, and dehydrocostus lactone were identified as the key components, and RAC-alpha serine/threonine-protein kinase (AKT1), prostaglandin-endoperoxide synthase 2 (PTGS2), interleukin 1 beta (IL1B), caspase-3 (CASP3), and CASP8 were selected as the core targets. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment results revealed the pharmacological mechanism of Aucklandiae Radix against gastric ulcer related to many biological processes and pathways, including antibacterial, anti-inflammatory, prostaglandin receptor response, and apoptosis. Molecular docking verification showed that the key components and core targets had good binding affinities. In the in vivo experiments, Aucklandiae Radix notably relieved the gastric ulcer by reducing the levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and myeloperoxidase (MPO) while improving the gastric histopathological features. Conclusion: The overall findings suggest that Aucklandiae Radix treats gastric ulcer with a multi-component, multi-target, and multi-mechanism model.