title: Determinants of plasma leptin concentration in postmenopausal women.
abstract: This investigation examined the influence of hormone replacement therapy on plasma leptin concentrations in postmenopausal women and sought to determine if a relationship existed between plasma leptin, the thermoregulatory cytokine interleukin-1 (IL-1), and basal body temperature. Twenty-two women (54-71 years of age) were studied: eight were not taking hormone replacement, seven took oral estrogen only, and seven took oral estrogen plus progestin. Morning oral temperature, plasma leptin concentration, and mononuclear cell secretion of IL-1beta, IL-1 receptor antagonist (IL-1Ra), and soluble IL-1 receptor type II (sIL-1RII) were measured. Plasma leptin concentrations were not affected by hormone replacement therapy, but were inversely related to years since menopause (R = -0.48, P = 0.02) and were proportional to IL-1 activity (the balance of IL-1beta/IL-1Ra secretion, R = 0.69, P = 0.001). Moreover, morning oral temperature was positively related to plasma leptin (P = 0.03), after stratifying by progestin intake. These results support the concept that basal body temperature is regulated by a network of endocrine and immune mediators that are significantly influenced by age.
authors.affiliation: Noll Physiological Research Center, Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: Esther M
authors.initials: EM
authors.lastname: Brooks-Asplund
authors.forename: Carrie E
authors.initials: CE
authors.lastname: Tupper
authors.forename: Jane M
authors.initials: JM
authors.lastname: Daun
authors.forename: W Larry
authors.initials: WL
authors.lastname: Kenney
authors.forename: Joseph G
authors.initials: JG
authors.lastname: Cannon
mesh_terms: D000368:Aged; D000375:Aging / Q000276:immunology / Q000378:metabolism*; D001831:Body Temperature / Q000502:physiology; D015914:Estrogen Replacement Therapy; D004967:Estrogens / Q000008:administration & dosage; D005260:Female; D006801:Humans; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1 / Q000378:metabolism; D020738:Leptin / Q000097:blood*; D008875:Middle Aged; D017698:Postmenopause / Q000276:immunology / Q000378:metabolism*; D045167:Progesterone Congeners / Q000008:administration & dosage; D017472:Receptors, Interleukin-1 / Q000378:metabolism; D053574:Receptors, Interleukin-1 Type II; D054411:Receptors, Leptin; D012795:Sialoglycoproteins / Q000378:metabolism
chemical_list: D004967:Estrogens; C507763:IL1RN protein, human; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1; C515448:LEPR protein, human; D020738:Leptin; D045167:Progesterone Congeners; D017472:Receptors, Interleukin-1; D053574:Receptors, Interleukin-1 Type II; D054411:Receptors, Leptin; D012795:Sialoglycoproteins