Large Hart-Shrinking Compounds Linked to Viagra Family
In a groundbreaking development, a new study suggests that PDE1 inhibitors could offer a significant advancement in the treatment of heart failure and hypertrophy. The research, which was sponsored by Pfizer and the National Heart, Lung, and Blood Institute (NHLBI), is currently exploring the potential of Viagra in treating moderate heart failure and reducing hypertrophy.
The research team, comprising scientists from the University of Rochester Medical Center, Omeris Corp., University of Washington, and University of Alabama at Birmingham, is focusing on understanding the role of various phosphodiesterases in atherosclerosis, hypertension, and heart failure.
PDE1 inhibitors have been found to counteract heart failure and hypertrophy not only by modulating calcium-sensitive cyclic nucleotide pathways but also by promoting proteasomal degradation of misfolded proteins through PKA (Protein Kinase A)- and PKG (Protein Kinase G)-mediated mechanisms. This dual action helps to reduce pathological remodeling in the heart, potentially alleviating cardiac stress and remodeling associated with heart failure and hypertrophy.
Beyond their role in calcium-sensitive cyclic nucleotide modulation, PDE1 inhibitors activate PKA and PKG pathways, leading to improvements in proteostasis. This improvement helps to alleviate cardiac stress and remodeling associated with heart failure and hypertrophy.
The study also reveals that PDE1 inhibitors, when combined with drugs like Viagra (a PDE5 inhibitor) or beta blockers, enhance downstream signaling pathways that improve cardiac contractility, reduce hypertrophy, and prevent heart failure progression synergistically.
Viagra interferes with phosphodiesterases (PDEs) that break down cyclic guanosine monophosphate (cGMP), a molecular messenger that regulates heart muscle cell growth. On the other hand, PDE1 inhibitors, like IC86340, further improve the balance of cAMP and cGMP, which together produce additive or synergistic cardioprotective effects.
The combination of IC86340 and Viagra in studies of isolated heart muscle cells eliminates hypertrophy to a greater degree than either compound alone. In live mice, IC86340 significantly reduces hypertrophy when both are exposed to the well-established hypertrophic agent isoproterenol.
Hypertrophy, or abnormal muscle growth in diseased hearts, is a major risk factor for the development of heart failure. The study suggests that a PDE1 inhibitor alone can shut down abnormal cardiac growth, and when combined with Viagra or beta blockers, may do so in more than one way.
This work was supported by the American Heart Association and the National Institutes of Health (NIH). The study, published in Circulation Research, suggests that compounds related to Viagra may counter heart failure in a different way. Further animal studies are needed to determine whether combination treatments featuring PDE1 inhibitors have value in heart failure.
PDE1 inhibitors may have potential for treating both hypertrophy in the heart and vascular diseases like hypertension and atherosclerosis. Studies are underway to determine the effect on hypertrophy in live mice with the genes for various PDE1 enzymes removed.
The study's findings could pave the way for new, more effective treatments for heart failure and hypertrophy, potentially improving the lives of the approximately 5.7 million Americans currently affected by heart failure.
- In the realm of science and health-and-wellness, researchers are investigating the potential of PDE1 inhibitors, such as IC86340, in managing chronic-diseases like heart failure and hypertrophy.
- Beyond their role in counteracting heart failure and hypertrophy, PDE1 inhibitors are being studied for their effects on medical-conditions like hypertension and atherosclerosis.
- The combined use of PDE1 inhibitors and drugs like Viagra or beta blockers could offer significant advancements in the treatment of cardiovascular-health issues, particularly heart failure and hypertrophy.
