Anti-inflammatory effects of vanadium-binding protein from Halocynthia roretzi in LPS-stimulated RAW264.7 macrophages through NF-κB and MAPK pathways

Vanadium-binding protein (VBP) was separated from the blood of the fresh sea urchin Halocynthia roretzi through (NH₄)₂SO₄ precipitation, Diethylaminoethyl Sepharose fast-flow ion-exchange chromatography, and Sephacryl S-200 high-resolution size-exclusion chromatography. The protein size and purification yield of VBP were 27 kDa and 5.5%, respectively. VBP exerted anti-inflammatory effects in lipopolysaccharide-stimulated RAW264.7 macrophages by downregulating iNOS expression and inhibiting nitric oxide production. VBP also suppressed the expression of pro-inflammatory mediators such as COX-2, IL-1β, IL-6, and TNF-α. The anti-inflammatory activity of VBP was further demonstrated in the NF-κB and MAPK inflammation pathways, in which VBP inhibited phosphorylation of signaling proteins such as p65, JNK, ERK1/2, and p38. Therefore, VBP from H. roretzi has anti-inflammatory effects and could potentially be used to treat inflammation.