TNF and periodontitis: Proanthocanydin- enriched extract from Myrothamnus flabellifolia, plants traditionally used for treatment of gingival inflammation and periodontitis in South Africa, decreased gene expression of IL-1β, IL-8 and TNF-α, and level of IL-6 in KB cells, pre-incubated with MF (10 μg/mL and 100 μg/mL) and infected with Porphyromonas gingivalis [33].