Inhibition of Sodium/Hydrogen Exchanger-1 in the Right Ventricle and Lung Dysfunction Induced by Experimental Pulmonary Arterial Hypertension in Rats.

Background: Life-threatening pulmonary arterial hypertension (PAH) still lacks a direct therapeutic approach targeted to the molecular defects associated with the disease. Here, we focus on the impaired regulation of intracellular acidity and sodium/calcium overload by testing the hypothesis that inhibiting NHE-1 (sodium/hydrogen exchanger isoform 1) with rimeporide enables the recovery of pulmonary and right ventricular dysfunctions in the Sugen5416/hypoxia PAH model in rats.

Methods And Results: Adult Sprague-Dawley male rats (n=44) rats were divided into 2 broad groups: control and Sugen5416/hypoxia.

Rimeporide as a first- in-class NHE-1 inhibitor: Results of a phase Ib trial in young patients with Duchenne Muscular Dystrophy.

Rimeporide, a first-in-class sodium/proton exchanger Type 1 inhibitor (NHE-1 inhibitor) is repositioned by EspeRare for patients with Duchenne Muscular Dystrophy (DMD). Historically, NHE-1 inhibitors were developed for cardiac therapeutic interventions. There is considerable overlap in the pathophysiological mechanisms in Congestive Heart Failure (CHF) and in cardiomyopathy in DMD, therefore NHE-1 inhibition could be a promising pharmacological approach to the cardiac dysfunctions observed in DMD.

Protective effects of rimeporide on left ventricular function in golden retriever muscular dystrophy dogs.

Background: Alterations in intracellular Na and Ca have been observed in patients with Duchenne muscular dystrophy (DMD) and in animal models of DMD, and inhibition of Na-H exchanger 1 (NHE1) by rimeporide has previously demonstrated cardioprotective effects in animal models of myocardial ischemia and heart failure. Since heart failure is becoming a predominant cause of death in DMD patients, this study aimed to demonstrate a cardioprotective effect of chronic administration of rimeporide in a canine model of DMD.

Methods: Golden retriever muscular dystrophy (GRMD) dogs were randomized to orally receive rimeporide (10 mg/kg, twice a day) or placebo from 2 months to 1 year of age.