Homoplantaginin is a flavonoid from a traditional Chinese medicine Salvia plebeia with antiinflammatory and antioxidant properties. Homoplantaginin could inhibit TNF-α and IL-6 mRNA expression, IKKβ and NF-κB phosphorylation.

Homoplantaginin shows IC50 of reduction level of DPPH radical at 0.35 μg/mL. In human hepatocyte HL-7702 cells exposed to H2O2, the addition of 0.1-100μg/mL of homoplantaginin significantly reduces lactate dehydrogenase leakage, and increases glutathione, glutathione peroxidase and superoxide dismutase in supernatant[1]. Homoplantaginin (0.1, 1, 10 μM) dose-dependently reduces expression of toll-like receptor-4 evoked by palmitic acid (100 μM). Homoplantaginin tightly controlls palmitic acid-induced reactive oxygen species to prevent nucleotide-binding domain-like receptor 3 (NLRP3) inflammasome activation by suppressing reactive oxygen species-sensitive thioredoxin-interacting protein, NLRP3, and caspase-1[2]. Pre-treatment of homoplantaginin on human umbilical vein endothelial cells significantly inhibits palmitic acid induced TNF-α and IL-6 mRNA expression, and IKKβ and NF-κB p65 phosphorylation. Homoplantaginin significantly modulates the Ser/Thr phosphorylation of IRS-1, improves phosphorylation of Akt and endothelial nitric oxide synthase, and increases NO production in the presence of insulin[3].