Liang et al studied combining AKBA (3) and As2O3 to inhibit the secretions of MMP-1, MMP-2, MMP-9, TNF-α, and IL-β.[22] The adjuvant-induced arthritis rats were treated with 0.90 g·kg−1 frankincense extract daily for 10 days. Here, MMP9 is linked to arthritic joint disease.