Human prostacyclin and thromboxane synthases: Molecular interactions, regulation, and pharmacology

Prostanoids are lipid mediators of the human body that are involved in the inflammation and platelet aggregation. Prostacyclin is a vasodilator and inhibitor of platelet aggregation, and a product of the enzymatic reaction catalyzed by prostacyclin synthase (PTGIS). Thromboxane is a vasoconstrictor and synthesized by thromboxane synthase (TBXAS1). An imbalance of prostanoids can accompany cardio-/cerebrovascular diseases and cancers. PTGIS and TBXAS1 are clinically relevant membrane-bound enzymes of the multigene family of cytochromes P450 (CYPs), also known as CYP8A1 and CYP5A1, respectively. Particular studies of these functional antagonists will contribute to the elucidation of pathogenic mechanisms. The purpose of this work was to analyze the literature landscape over a period of 2020-2024 in the field of biological, pharmacogenomic, and pharmacological features of PTGIS and TBXAS1 as well as to explore the potential of their regulation at the post-transcriptional and post-translational levels using systems biological analysis. The review discusses recent findings on the novel aspects of both synthases established in gene knockout and overexpression experiments, current preclinical pharmacology, and potential ways of gene expression regulation. Identification of protein-protein interactions and post-translational modifications appear to be the main options for modulating PTGIS and TBXAS1 activity. The microsomal CYPs are known to form complexes with each other and direct interactions of CYP2E1 with both synthases can probably lead to modulation of their activity. Progress in the preclinical development of low molecular weight compounds as inhibitors of TBXAS1 is more prospective than PTGIS that is applied as gene therapy biologicals for in vivo production of prostacyclin due to its noticeable anticancer and vasodilator effects.