MMP9 and pulmonary arterial hypertension: Yan et al. (2016) demonstrated that 30 mg/kg of BA (i.p. injection) relieved the hypoxia-induced PAH model by mitigating pulmonary hypertension, pulmonary arteriole, and right ventricular remodeling and ameliorating hypoxic cor pulmonale by suppressing the p38 MAPK pathway and the expression of matrix metalloprotein (MMP)-9.