title: Adiposity, leptin and stress reactivity in humans.
abstract: Evidence suggests that individuals who are more obese may be more responsive to stress. Stress activates the sympathetic nervous system (SNS) and the adipose-tissue cytokine leptin stimulates SNS activity in animals. We examined the relationship between adiposity, leptin and physiological responses to acute laboratory stress in 67 women. We predicted that individuals with greater adiposity and/or higher plasma leptin would be more stress-responsive. Adiposity was unrelated to cardiovascular or neuroendocrine stress reactivity. However, women with larger waists had greater stress-induced increases in plasma leptin and interleukin-1 receptor antagonist (IL-1Ra). Similarly, women with higher basal leptin displayed greater stress-induced increases in heart rate and plasma interleukin-6, and larger decreases in heart rate variability and cardiac pre-ejection period. Heightened cardiovascular and inflammatory stress responses are predictive of future cardiovascular risk. Our findings suggest that the cytokines leptin and IL-1Ra may play a role in the association between obesity, stress and cardiovascular health.
authors.affiliation: Psychobiology Group, Department of Epidemiology and Public Health, University College London, 1-19 Torrington Place, London WC1E 6BT, United Kingdom. l.brydon@ucl.ac.uk
authors.forename: Lena
authors.initials: L
authors.lastname: Brydon
mesh_terms: D050154:Adiposity; D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001794:Blood Pressure / Q000502:physiology; D015992:Body Mass Index; D016207:Cytokines / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D053590:Interleukin 1 Receptor Antagonist Protein / Q000097:blood; D020738:Leptin / Q000097:blood*; D009483:Neuropsychological Tests; D012463:Saliva / Q000378:metabolism; D013315:Stress, Psychological / Q000097:blood* / Q000503:physiopathology*; D013997:Time Factors; D055815:Young Adult
chemical_list: D016207:Cytokines; C507763:IL1RN protein, human; D053590:Interleukin 1 Receptor Antagonist Protein; D020738:Leptin; D006854:Hydrocortisone