Serum Pharmacochemistry-Guided DARTS-MS Profiling Reveals Potential Mechanisms of Caragana jubata Against Hypoxic Pulmonary Hypertension

Hypoxic pulmonary hypertension (HPH) is a progressive vascular disease characterized by an abnormal increase in pulmonary arterial pressure resulting from pulmonary vasoconstriction and pulmonary vascular remodeling (PVR). Excessive proliferation and migration of pulmonary artery smooth muscle cells (PASMCs) are key drivers of PVR. Caragana jubata (Pall.) Poir. (C. jubata), known as “zuomaoxing” in Tibetan medicine, is traditionally used to treat blood-related disorders. However, the potential preventive and therapeutic effects of C. jubata on HPH remain unclear. Here, we integrated in vivo pharmacology, serum pharmacochemistry, PASMC assays, DARTS-MS chemoproteomics, and pathway validation to investigate the effects of C. jubata ethanol extract (ECJ) on HPH-associated PVR and the effects of a serum-exposed candidate component on CoCl2-induced PASMC activation. In HPH rats, ECJ reduced mean pulmonary arterial pressure and alleviated right ventricular hypertrophy and PVR. Serum pharmacochemistry detected 47 ECJ-derived serum-exposed features, including one prototype putatively annotated as ginkgolide J. Ginkgolide J attenuated CoCl2-induced PASMC proliferation, Ki-67 positivity, and migration without significantly affecting PASMC viability. DARTS-MS identified 1235 ginkgolide J-associated protease-susceptibility candidate proteins, and pathway validation indicated that ginkgolide J suppressed CoCl2-induced MEK1/ERK1/2 activation. These findings suggest that ECJ has potential value against HPH-associated PVR and that ginkgolide J is a candidate anti-proliferative compound in PASMCs.