Neurophysin I: a reliable, novel, and robust biomarker for oxytocin.
European journal of endocrinology March 27, 2025 Cihan Atila, Andi Nikaj, Svenja Leibnitz et al. 9 citations
Neurophysin I (NP-I), a stable byproduct of the oxytocin precursor, can serve as a reliable biomarker for oxytocin secretion when stimulated by MDMA. In a double-blind, placebo-controlled crossover study, 15 patients with hypothalamic-posterior-pituitary dysfunction and 15 matched healthy controls received a single 100 mg dose of MDMA or placebo. In healthy controls, MDMA caused an 8-fold increase in oxytocin (peak: 624 pM) and a 20-fold increase in NP-I (peak: 1508 pM). Patients showed no notable oxytocin increase (peak: 92 pM) and only a mild NP-I rise (peak: 263 pM). The difference in NP-I area under the curve between groups was significant (2340 pM·5 h; 95% CI, 1462-3218). NP-I measurement offers a way to assess oxytocin secretion, aiding research into conditions like autism, anxiety, and depression.