SIRT3 also seems important in pulmonary arterial hypertension (PAH) since pulmonary artery smooth muscle cells (PASMC) from patients with PAH display down-regulation of SIRT3; Sirt3−/− mice spontaneously develop PAH and SIRT3 restoration in a rodent model and Sirt3−/− mice PASMC attenuates the disease phenotype [154]. The gene discussed is SIRT3; the disease is pulmonary arterial hypertension.