Shenlian Decoction Ameliorates LPS-Related Inflammation in db/db Mice: Coupling Network Pharmacology With Experimental Verification

Background: Shenlian (SL) decoction, a renowned traditional Chinese formula for diabetes mellitus, has also been employed to treat intestinal disorders. Previous studies have demonstrated the efficacy of SL decoction in regulating blood glucose and intestinal bacteria. Nevertheless, further analysis is required to elucidate the mechanistic link between SL decoction-mediated improvement of intestinal function and treatment of Type 2 diabetes mellitus (T2DM). Methods: Firstly, the active ingredients of SL decoction were sourced from the Traditional Chinese Medicine System Pharmacology (TCMSP) database, with putative targets of active ingredients being predicted using the same database. Secondly, the Online Mendelian Inheritance in Man (OMIM) and GeneCards databases were employed to screen the aforementioned targets that act on T2DM, and protein-protein interaction (PPI) networks were constructed in accordance with the results. Thirdly, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted using the Database for Annotation, Visualization, and Integrated Discovery (DAVID), which resulted in a comprehensive analysis of the association between SL decoction for the treatment of T2DM and the modulation of intestinal functions. Finally, the effect of the SL decoction on predicted lipopolysaccharide (LPS)-related targets, as well as intestinal function markers, was validated through in vivo experimentation. Results: A total of 36 active ingredients and 145 potential targets of SL decoction were predicted. GO enrichment analysis indicated that the principal biological processes by which the SL decoction acted against T2DM were responses to LPSs, while KEGG enrichment analysis identified the nuclear factor kappa B (NF-κB) signaling pathway and toll-like receptor signaling pathway as the key pathways involved. The in vivo experiments showed that SL decoction improved glycolipid metabolism indexes, inflammatory factor levels, and LPS levels in db/db mice. The immunohistochemical results demonstrated that the SL decoction restored the expression of Occludin, Claudin-1, and ZO-1 in the intestine and inhibited the expression of toll-like receptor 4 (TLR4), myeloid differentiation primary response gene 88 (MYD88), and NF-κB in both the intestine and pancreas. Furthermore, it may influence the levels of short-chain fatty acids (SCFAs) in feces. Conclusions: This research investigated the multigene pharmacological mechanism of SL decoction against T2DM using network pharmacology and in vivo experiments. SL decoction treatment of T2DM may reverse inflammation by inhibiting LPS-related pathway activation and improving intestinal function.