Berberine Modulates LPA Function to Inhibit the Proliferation and Inflammation of FLS-RA via p38/ERK MAPK Pathway Mediated by LPA₁

Figure 5

Berberine inhibits the proliferation and inflammation of FLS-RA through the p38/ERK MAPK pathway partially mediated by LPA₁. (a) LPA treatment for 24 h promotes cell proliferation, as detected by MTT assay. (b) The LPA-induced pro-proliferative effect is reversed by the addition of berberine, as measured by MTT assay. (c, d, e) Pretreatment with berberine remarkably restrains the expression of TNF-α, IL-6, and K-ras, and such condition is not obviously changed after the addition of berberine. (f) Ki16425 inhibits cell proliferation, as indicated by MTT assay. (g) 1 h Ki16425 pretreatment in FLS-RA before incubation with berberine for 24 h measured by MTT assay. (h, i) Ki16425 pretreatment in FLS-RA distinctly downregulates the expression of TNF-α and IL-6, and such condition is not obviously changed after the addition of berberine. (j) Western blotting and RT-PCR show that LPA pretreatment in FLS-RA significantly promotes the expression of K-ras, c-Raf, P-p38, and P-ERK1/2, while such condition is reversed in the presence of berberine pretreatment. , , and . Ctrl, control group; LPA₁, lysophosphatidic acid receptor 1; LPA, lysophosphatidic acid; FLS-RA, fibroblast-like synovial cells of rheumatoid arthritis.

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