Oxytocin: Potential to mitigate cardiovascular risk

Cardiovascular disease (CVD) remains the leading cause of death worldwide, despite multiple treatment options. In addition to elevated lipid levels, oxidative stress and inflammation are key factors driving atherogenesis and CVD. New strategies are required to mitigate risk and most urgently for statin-intolerant patients. The neuropeptide hormone oxytocin, synthesized in the brain hypothalamus, is worthy of consideration as a CVD ancillary treatment because it moderates factors directly linked to atherosclerotic CVD such as inflammation, weight gain, food intake and insulin resistance. Though initially studied for its contribution to parturition and lactation, oxytocin participates in social attachment and bonding, associative learning, memory and stress responses. Oxytocin has shown promise in animal models of atherosclerosis and in some human studies as well. A number of properties of oxytocin make it a candidate CVD treatment. Oxytocin not only lowers fat mass and cytokine levels, but also improves glucose tolerance, lowers blood pressure and relieves anxiety. Further, it has an important role in communication in the gut-brain axis that makes it a promising treatment for obesity and type 2 diabetes. Oxytocin acts through its receptor which is a class I G-protein-coupled receptor present in cells of the vascular system including the heart and arteries. While oxytocin is not used for heart disease at present, residual CVD risk remains in a substantial portion of patients despite multidrug regimens, leaving open the possibility of using the endogenous nonapeptide as an adjunct therapy. This review discusses the possible role for oxytocin in human CVD prevention and treatment.

In silico profiling the interaction mechanism of 2,5-diketopiperazine derivatives as oxytocin antagonists

Oxytocin plays a vital role in the occurrence of preterm birth by interacting with oxytocin receptor (OTR), and thus OTR antagonists provide effective approaches for the treatment of early birth. Presently, for purpose of exploring the structural traits affecting the antagonism potency, the up-to-date largest set of 121 2,5-diketopiperazine derivatives as OTR antagonists was subjected to ligand-based three-dimensional quantitative structure-activity (3D-QSAR) analysis applying comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) methods. The resultant optimal CoMSIA model displays proper validity and predictability with cross-validated correlation coefficient Q² = 0.614, non-cross-validated correlation coefficient R²_ncv = 0.969 and predicted correlation coefficient R²_pre = 0.912 for the test set of compounds, respectively. In addition, docking study was carried out for further elucidating the binding modes of OTR antagonists. The final docking cavity was located among the TM2-TM7 helices of the target protein and proved to be the same as described by other scholars' researches of other type of OTR antagonists. The major amino acids forming the cavity are Q92, Q96, K116, Q119, V120, M123, G196, I201, Q295, W288, F311 and M315. Representative compound 118 forms two H-bonds with Q119 and two H-bonds with Q295, with also a π - π stacking effect with F311, respectively. Meanwhile, as a supplementary tool to study the antagonists' conformation in the binding cavity, molecular dynamics (MD) simulation was also performed to further elucidate the changes in the ligand-receptor complex. We hope that the obtained models and information may help to provide an insight into the interaction mechanism of OTR antagonists and facilitate the design and optimization of novel antagonists for preventing premature birth.