Lack of Adult-Type Salivary Cortisol Circadian Rhythm in Hospitalized Preterm Infants

Circadian rhythms are controlled by an endogenous time-keeping system oscillating approximately on a 24-h cycle under constant conditions. These rhythms depend on a network of interacting genes and proteins, including transcriptional activators such as CLOCK, NPAS2, and ARNTL (BMAL1), which induce transcription of the clock genes Period ( Per1 , Per2 , and Per3 ) and Cryptochrome ( Cry1 and Cry2 ). Human salivary cortisol and melatonin follow a clear circadian rhythm as well. Disruption of the circadian rhythm and sleep-wake cycles are considered risk factors for a variety of health problems, especially hypertension and other cardiovascular and metabolic diseases. Here we put together practical methods for assessing circadian rhythms in adult subjects conducted by each individual. This method is non-invasive, inexpensive and provides a predictive profile of an individual’s circadian rhythm related to clock-controlled gene expression in buccal cells, salivary cortisol, salivary melatonin, and subject’s activity or sleep. Subjects are instructed on how to obtain buccal cells using swabs (Whatman OmniSwab) from the inside of their cheeks and collect saliva using salivettes (Sarstedt) every 4 hours starting at 6am, for 2 consecutive days. Subjects also wear actigraphy watches (Phillips Respironics) during the 2 days, to record their activity, light exposure and estimates of sleep times. To monitor adherence to correct time point collections, each subject is given an electronic vial called eCAP (Information Mediary Corp) that records the exact time the container is opened to place samples once collected. We demonstrate feasibility to extract up to 150ng/μl of RNA (Ambion RNAqueous-Micro Total RNA Isolation Kit) from buccal cells swabs. Salivary melatonin and cortisol are measured by radioimmunoassay (Buhlmann Lab) with melatonin peak levels ranging from 14 to 23 pg/ml and cortisol peak levels ranging from 10 to 24 ng/ml. We suggest that buccal cell expression of clock-controlled genes, salivary melatonin, salivary cortisol, and actigraphy data are valuable in providing reliable assessment of human circadian rhythm profiles under a variety of conditions.

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Maternal factors regulating preterm infants' responses to pain and stress while in maternal kangaroo care

Revista Latino-Americana de Enfermagem ◽

10.1590/s0104-11692012000300003 ◽

2012 ◽

Vol 20 (3) ◽

pp. 435-443 ◽

Cited By ~ 4

Author(s):

Thaíla Corrêa Castral ◽

Fay Fathalee Warnock ◽

Laiane Medeiros Ribeiro ◽

Maria Gorete Lucena de Vasconcelos ◽

Adriana Moraes Leite ◽

...

Keyword(s):

Heart Rate ◽

Preterm Infants ◽

Salivary Cortisol ◽

Mental Condition ◽

Bivariate Analysis ◽

Maternal Factors ◽

Kangaroo Care ◽

Explanatory Variables ◽

Neonatal Response ◽

Cortisol Levels

The relationship between maternal factors and the response of preterm infants to pain and stress experienced during heel puncture while in maternal kangaroo care was investigated. This descriptive study included 42 mothers and their preterm infants cared for in a neonatal unit. Data were collected in the baseline, procedure, and recovery phases. We measured the neonates' facial actions, sleep and wake states, crying, salivary cortisol levels, and heart rate, in addition to the mothers' behavior, salivary cortisol levels, and mental condition. The influence of the maternal explanatory variables on the neonatal response variables were verified through bivariate analysis, ANOVA, and multiple regression. The mothers' behavior and depression and/or anxiety did not affect the neonates' responses to pain and stress, though the mothers' levels of salivary cortisol before the procedure explained the variance in the neonates' levels of salivary cortisol after the procedure (p=0.036). Additionally, the mothers' baseline levels of salivary cortisol along with the neonates' age explained the variance in the neonates' heart rate (p=0.001). The ability of mothers to regulate their own stress contributed to the infants' responses to pain and stress.

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Salivary Cortisol Reactivity in Preterm Infants in Neonatal Intensive Care: An Integrative Review

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph13030337 ◽

2016 ◽

Vol 13 (3) ◽

pp. 337 ◽

Cited By ~ 24

Author(s):

Evalotte Mörelius ◽

Hong-Gu He ◽

Shefaly Shorey

Keyword(s):

Intensive Care ◽

Preterm Infants ◽

Salivary Cortisol ◽

Neonatal Intensive Care ◽

Integrative Review ◽

Cortisol Reactivity

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SALIVARY CORTISOL AND METABOLIC SYNDROME COMPONENT’S ASSOCIATION

ABCD Arquivos Brasileiros de Cirurgia Digestiva (São Paulo) ◽

10.1590/0102-672020180001e1351 ◽

2018 ◽

Vol 31 (1) ◽

Cited By ~ 1

Author(s):

Grasiane Izidorio GARBELLOTTO ◽

Fernanda Jardim REIS ◽

Ana Maria Pandolfo FEOLI ◽

Carla Haas PIOVESAN ◽

Andréia da Silva GUSTAVO ◽

...

Keyword(s):

Physical Activity ◽

Risk Factors ◽

Metabolic Syndrome ◽

Circadian Rhythm ◽

Salivary Cortisol ◽

Cross Sectional Study ◽

Elevated Blood ◽

Sectional Study ◽

Cross Sectional ◽

Pituitary Adrenal Axis

ABSTRACT Background: Actually the lifestyle exposes the population to several risk factors related to alimentary habits and less physical activity that contributes to chronic diseases appearance worldwide. Aim: To analyze the association between salivary cortisol and the components of metabolic syndrome. Methods: This is a cross-sectional study. As part of it, 28 individuals aged 30-59 years presenting three or more of the following findings: CA: ≥88 cm for women and ≥102 cm for men; SBP>130 mmHg and DBP>85 mmHg; GL>100 mg/dl; TG>150 mg/dl; HDL<40 mg/dl for men and <50 mg/dl for women. Was performed analysis of salivary cortisol (by radioimmunoassay) from 25 salivary samples collected throughout the day, for evaluating changes in the circadian rhythm of this hormone (8AM, noon and 8PM). Results: 28 evaluated individuals had a mean age of 51.9±7.5 years, mostly women (64.3%) and a mean of BMI 33.6±3.2 kg/m². The cortisol level from the 8AM averaged 18.7±4.8 ng/dlL. Individuals with FPG>110mg/dl, have significantly lower average levels of cortisol than ones with FPG <110 (12.8±5,2 vs. 17.3±4.2). Significant correlations were HOMA vs. WC (r=0,465; p˂0,005) and TG (r=0,473; p˂0,005), WC vs. FG (r=0,446; p˂0,005) and BMI (r=0,730; p˂0.0001); TG vs. HDL (r=0,441 p˂0,005) and FG (r=0,440; p˂0,005). Conclusion: Morning salivary cortisol in subjects with chronically elevated blood glucose can represent a downregulation of the hypothalamic-pituitary adrenal axis. This is an important finding not yet well investigated.

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