Objectives: After revolutionized treatment of erectile dysfunction (ED) with phosphodiesterase-5 inhibitors (PDE5) inhibitors, approximately 30% of patients are non-responsive. An important cause of this is vascular and smooth muscle dysfunction, as well as nerve atrophy. Stem cells are characterized by anti-inflammatory activities, as well as possibility of differentiating into tissue relevant...

Usnic acid (UA) is a secondary metabolite of lichens that exhibits wide range biological activities. Previously, we found UA derivatives are effective inhibitors tyrosyl-DNA phosphodiesterase 1 (TDP1). It can remove covalent complex DNA-topoisomerase (TOP1) stabilized by the TOP1 inhibitor topotecan, neutralizing effect drugs. TDP1 removes damage at 3′ end DNA caused other anticancer agents. Th...