Endocrine Abstracts

Keywords: sugar substitute agent exposures, nutritional biology, neuroendocrine system, oxytocin

Human homeostasis is maintained by the complex functioning of the psycho-neuroendocrine-immune system. If a disturbance is generated in this neuroendocrine system for any reason, it can trigger pathogenic processes. One of the factors disturbing homeostasis today may be changes in dietary habits, e.g. through the use of undue sweeteners (e.g. stevia, xylitol etc.). These substances may alter neuroendocrine regulation if they affect natural metabolic processes. In the present work we aim to follow the changes in oxytocin (OT) relase induced by certain sugar substituting agents. Continuing our research on this topic, where we have already explored the effects induced in AVP ablation. In our work, we treated Wistar (♂) rats in vivo with gastrointestinally sweetening agents (aspartame, stevia, saccharin, xylitol) while monitoring their toxicity parameters. At the end of the treatments, in vitro neurohypophysis monolayer cell culture models (NH) were prepared (enzymatic /trypsin, collagenase, dyspase enzymes/ and mechanical /d=80 μm neylon-blutex filter/ dissociation; DMEM+10% FCS+10U/ml Pen+Strep culture medium). These were used to study OT regulation after viability, specific-, aspecific function control. We measured the basal OT release of NH wells from confluent cultures formed after in vivo treatment and also determined OT release in vitro in the presence of additional aspartame, stevia, saccharin, xylitol (1 mg/100 mL culture medium). Our results were developed using RIA, ELISA, and Lowry methods. ANOVA was used for statistical analysis. We found that after in vivo treatment, each sweetener modulated the basal OT secretion of NH cultures in a downward direction, which was followed by a stronger decrease in OT secretion after in vitro treatments at the contact cell level. When these data are compared with the AVP release results, it can be seen that OT secretion is more sensitive to the applied sugar substitutes than AVP. The experiments seem to confirm an endocrine modulating effect, which justifies further studies (supported by EFOP-3.6.1-16-2016-00008, EFOP3.4.3-16-2016-00014; TAMOP-4.2.4.A/2-11/1-2012-0001).