Moreover, leech components’ ability to promote nitric oxide (NO) release by up-regulating endothelial nitric oxide synthase (eNOS) enhances vascular relaxation, improves coronary perfusion, and contributes to better endothelial function, all of which are essential for managing CHD (Junren et al., 2021; Jaishankar et al., 2023; Sun et al., 2025). This evidence concerns the gene NOS3 and coronary artery disorder.