To identify key genes and inflammatory signaling pathways involved in the anti-inflammatory effects of Hedysarum polybotrys polysaccharide (HPS) in a rat model of endotoxin-induced uveitis (EIU).

EIU was induced in Wistar rats through subcutaneous injection of lipopolysaccharide (LPS, 200 μg) and the rats were then randomly assigned to EIU group (n=5) and the HPS intervention group (n=5). HPS (400 mg/kg, intraperitoneally) or its carrier was administered 24h and 1h prior to EIU induction. Eyes were examined and enucleated 24h post-induction, and total RNA was extracted from the iris-ciliary body. Gene expression microarrays were used to identify differentially expressed genes (DEGs), followed by bioinformatics analyses, including gene ontology (GO) and pathway analysis. Key findings were not experimentally validated at the mRNA or protein level.

A total of 322 DEGs were identified, comprising 254 mRNA and 68 lncRNA genes. GO analysis revealed significant functional categories, including response to LPS. Pathway analysis identified key signaling pathways involved in uveitis, such as cytokine-cytokine receptor interactions. Notably, 16 mRNA and 7 lncRNA DEGs emerged as central nodes in the gene correlation network.

HPS exerts its anti-inflammatory effects through coordinated signaling pathways, offering insights into potential therapeutic targets for managing uveitis.

To investigate the effect of morroniside (Mor) on lipopolysaccharide (LPS)-treated iris pigment epithelial cells (IPE).

IPE cells were induced by LPS and treated with Mor. Cell proliferation was detected by cell counting kit (CCK) -8, apoptosis was detected by flow cytometry, the levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-8 were measured by enzyme-linked immunosorbent assay (ELISA) kits, and the protein expression of TLR4, JAK2, p-JAK2, STAT3, and p-STAT3 was analyzed by Western blotting. In addition, overexpression of TLR4 and Mor treatment of LPS-stimulated IPE cells were also tested for the above indices.

Mor effectively promoted the proliferation and inhibited the apoptosis of LPS-treated IPE cells. In addition, Mor significantly reduced the levels of TNF-α, IL-6, and IL-8 and significantly inhibited the expression of TLR4, p-JAK2, and p-STAT3 in LPS-treated IPE cells. The effect of Mor on LPS-treated IPE cells was markedly attenuated after overexpression of TLR4.

These findings suggest that Mor may ameliorate LPS-induced inflammatory damage and apoptosis in IPE through inhibition of TLR4/JAK2/STAT3 pathway.