Adipose-derived regenerative cell therapy inhibits the progression of monocrotaline-induced pulmonary hypertension in rats.

Aims: Functional and structural changes in pulmonary vasculature characterize pulmonary arterial hypertension (PAH) and the prognosis of advanced PAH remains poor despite progress in pharmacotherapy. Adipose-derived regenerative cells (ADRCs) promote cell regeneration at pathological sites and comprise a novel therapy for ailments of various organs. We investigated the effects of ADRC therapy in rat models of monocrotaline (MCT)-induced pulmonary hypertension (PH) and the underlying mechanisms.

Main Methods: Rats were assigned to Control and MCT groups without and with (M/A) intravenous transfusion of seven million ADRCs on day 7. We echocardiographically evaluated pulmonary hypertension as pulmonary artery flow acceleration time (PAAT) and deceleration (PADc). Right ventricular (RV) systolic pressure was measured by catheterization on day 28 and then pathological changes in pulmonary vessels were assessed. We analyzed PAH-associated gene expression on day 14 using real-time RT-PCR.

Key Findings: Echocardiography and RV catheterization showed that ADRC therapy inhibited PH development (assessed as PAAT, PADc, and RV systolic pressure) at day 28 (MCT vs. M/A, P<0.05). Pulmonary vascular remodeling was also inhibited (vessel wall thickness: MCT vs. M/A, P<0.01). Messenger RNA levels of endothelin (ET) A and B receptors, ET-1 and transforming growth factor (TGF)-β increased in the lungs by MCT were suppressed by ADRCs (MCT vs. M/A, P<0.05).

Significance: The development of PH was inhibited by ADRCs through suppressing changes in the expression of genes associated with ET and TGF-β systems. We believe that ADRC therapy could serve as a novel strategy for treating PH.