Mother-Toddler Cortisol Synchrony Moderates Risk of Early Internalizing Symptoms (vol 23, pg 232, 2018)
INFANCY
Authors: Northrup, Jessie B.; Iverson, Jana M.
Abstract
Research examining mother-infant interactions indicates a close connection between vocal and gaze behavior. The present longitudinal study examined the development of both intraindividual and dyadic coordination of vocal and gaze behavior in mother-infant dyads at 3, 6, 9, and 12 months. Mother and infant vocalization and gaze behavior during in-home toy play interactions were coded on a moment-by-moment basis and coordinations (i.e., co-occurrences and sequences of behavior) were compared to randomized baselines in order to determine whether coordinate exceeded chance levels. Infants timed their own vocalizations with gaze to partner's face and inhibited vocalizations during gaze to objects at greater than chance levels across the first year. Mother's displayed above-chance intraindividual coordination of vocalizations and gaze to partner's face and objects. Mothers and infants demonstrated dyadic coordination of vocalizations and gaze at above-chance levels, but developmental change and leading-following dynamics varied based on gaze location (i.e., face vs. object). Results emphasize the importance of examining coordination across communication modalities and of considering bidirectional influences on mother and infant vocal and gaze behavior.
Long-term magnesium supplementation improves glucocorticoid metabolism: A post-hoc analysis of an intervention trial
CLINICAL ENDOCRINOLOGY
Authors: Schutten, Joelle C.; Joris, Peter J.; Minovic, Isidor; Post, Adrian; van Beek, Andre P.; de Borst, Martin H.; Mensink, Ronald P.; Bakker, Stephan J. L.
Abstract
Objective Increasing magnesium intake might reduce the risk of cardiovascular disease (CVD). Whether potential effects on cortisol contribute to these beneficial effects on cardiovascular health remains unclear. We therefore studied effects of long-term oral magnesium supplementation on glucocorticoid metabolism, specifically on the excretion of urinary cortisol, cortisone and their metabolites, as well as on the ratios reflecting enzymatic activity of 11 beta-hydroxysteroid dehydrogenases (11 beta-HSDs) and A-ring reductases. Design A post-hoc analysis of a randomized trial with allocation to a magnesium supplement (350 mg/day) or a placebo for 24-week. Patients Forty-nine overweight men and women, aged between 45 and 70 years. Measurements Cortisol, cortisone and their metabolites (tetrahydrocortisol [THF], allo-tetrahydrocortisol [allo-THF] and tetrahydrocortisone [THE]) were measured in 24-h urine samples. Enzymatic activities of 11 beta-HSD overall and of 11 beta-HSD type 2 were estimated as the urinary (THF + allo-THF [THFs])/THE and cortisol/cortisone ratios, respectively. A-ring reductase activity was assessed by ratios of THF/allo-THF, allo-THF/cortisol, THF/cortisol and THE/cortisone. Results After 24-week, urinary cortisol excretion was decreased in the magnesium group as compared with the placebo group (-32 nmol/24-h, 95% CI: -59; -5 nmol/24-h, p = .021). Ratios of THFs/THE and cortisol/cortisone were decreased following magnesium supplementation by 0.09 (95% CI: 0.02; 0.17, p = .018) and 0.10 (95% CI: 0.03; 0.17, p = .005), respectively. No effects were observed on A-ring reductase activity. Conclusions We observed a beneficial effect of magnesium supplementation towards a lower 24-h urinary cortisol excretion together with an increased activity of 11 beta-HSD type 2. Our findings may provide another potential mechanism by which increased magnesium intake lowers CVD risk (ClinicalTrials.gov identifier: NCT02235805).