Hormone and cytokine circadian alteration in non-small cell lung cancer patients.

Alterations in hormone secretion and cytokine levels have been evidenced in many neoplastic diseases. In this study we have evaluated the circadian profile of growth hormone (GH), insulin-like growth factor-1 (IGF-1), interleukin-2 (IL2), melatonin (MEL) and cortisol (COR) serum levels in non-small cell lung cancer patients. Blood was sampled every 4 h for 24 h in 11 healthy (H) men (ages 35-53 years) and 9 men with stage 2, 3 or 4 non-small cell lung cancer (C) (ages 43-63 years).

Alteration of circadian rhythmicity of CD3+CD4+ lymphocyte subpopulation in healthy aging.

The CD4+ T helper/inducer and the CD8+ T suppressor/cytotoxic are major lymphocyte subsets that play a key role in cell-mediated immunity. Aging-related changes of immune function have been demonstrated. The purpose of this study is to analyze the dynamics of variation of these specific lymphocyte subsets in the elderly.

Neuro-endocrine correlations of hypothalamic-pituitary-thyroid axis in healthy humans.

Neuro-endocrine hormone secretion is characterized by circadian rhythmicity. Melatonin, GRH and GH are secreted during the night, CRH and ACTH secretion peak in the morning, determining the circadian rhythm of cortisol secretion, TRH and TSH show circadian variations with higher levels at night. Thyroxine levels do not change with clear circadian rhythmicity.

Circadian rhythmicity of lymphocyte subpopulations and relationship with neuro-endocrine system.

Lymphocyte subpopulations present circadian variation of some of their subsets, this variation may influence magnitude and expression of the immune responses and may be related to the variation of neuro-endocrine humoral factors. In our study cortisol, melatonin, TRH, TSH, FT4, GH, IGF1 and IL2 serum levels were measured and lymphocyte subpopulation analyses were performed on blood samples collected every four hours for 24 hours from 11 healthy male subjects aged 38-55 years. A clear circadian rhythm was validated for cortisol serum levels, CD8, CD16, TcRδ1 with acrophase in the morning and at noon, and for melatonin, TRH, TSH, GH, CD3, CD4, CD4/CD8 ratio, HLA-DR, CD20 and CD25 with acrophase at night.

A possible mechanism for altered immune response in the elderly.

Background: Reciprocal influences and bidirectional connections among the nervous, endocrine and immune systems, mediated by shared neuroendocrine hormones, chemo/cytokines and binding sites contribute to the maintainment of body homeostasis. The hypothalamus-pituitary axis may play an immunomodulating role and influence cellular immune responses by releasing various hormones and neuropeptides into the blood with direct modulatory action on the immune effectors, or by regulating the hormonal secretion of peripheral endocrine glands. Aging is associated with changes in immune function.