Discussions and perspectives regarding oxytocin as a biomarker in human investigations

Human endogenous oxytocin and its neural correlates show adaptive responses to social touch based on recent social context

“…Different methods for detecting plasma OT have yielded different and sometimes uncorrelated sets of value ranges, with measurement issues centering around the selectivity with which testing components detect bound or unbound protein, or whole or fragmentary molecules. Cerebrospinal fluid (CSF) has consistently been found to correlate more strongly with brain OT levels than does plasma OT, while CSF and plasma OT measurements have shown weak or no correlation ( Caicedo Mera et al, 2021 ). However, at least a proportion of inconsistencies in reported findings may depend on a historical tendency to investigate basal levels, rather than acute stimuli more likely to evoke coordinated, biologically-meaningful responses across the central and peripheral nervous systems.…”

Microbes, oxytocin and stress: Converging players regulating eating behavior

“…RAGE receptors have been shown to be crucial for the effect of exogenous Oxt on social behavior, such as bonding and parenting 67,68 . One additional difficulty in studying Oxt levels in preclinical and especially clinical trials is the poor performance of Oxt enzyme‐linked immunoassays (ELISAs) that yield highly variable, inconsistent, and uncorrelated results even for the same sample 69–72 . Furthermore, Oxt has a short half‐life (around 4–6 min), 73,74 is broken down by tissue proteases and binds to plasma proteins which makes the quantification of Oxt levels, particularly in plasma, challenging.…”

“…67,68 One additional difficulty in studying Oxt levels in preclinical and especially clinical trials is the poor performance of Oxt enzyme-linked immunoassays (ELISAs) that yield highly variable, inconsistent, and uncorrelated results even for the same sample. [69][70][71][72] Furthermore, Oxt has a short half-life (around 4-6 min), 73,74 is broken down by tissue proteases and binds to plasma proteins which makes the quantification of Oxt levels, particularly in plasma, challenging. Thus, the field would benefit from novel detection methods enabling accurately determine how (microbiome-targeting) interventions modify…”

Promising applications of human-derived saliva biomarker testing in clinical diagnostics

“…Oxytocin, a neuro-hormone produced by the hypothalamus and finally released from the posterior hypophysis, 221 is distributed in the periphery and central nervous system. 222 Over the past decades, oxytocin has been extensively studied due to its important function in reproductive physiology, affective processes, and social behaviors, including stimulating the milk production in mammary glands, promoting the uterine smooth muscle contraction during labor, regulating parental nurturing behaviors and empathy-related behaviors.…”

“… 222 Over the past decades, oxytocin has been extensively studied due to its important function in reproductive physiology, affective processes, and social behaviors, including stimulating the milk production in mammary glands, promoting the uterine smooth muscle contraction during labor, regulating parental nurturing behaviors and empathy-related behaviors. 221 , 223 , 224 In addition, oxytocin was reported to be associated with pain relief in aging. 222 A negative correlation was also found between oxytocin levels and depression/anxiety.…”