[Influence of the pineal gland's factors on the cell composition of the bone marrow in animals of different age in conditions of changed thymus functional state].

Advances in gerontology = Uspekhi gerontologii2011PMID: 21809621

Animal StudyEpitalon

Plain Language Summary

Epithalamin and melatonin influenced bone marrow cell composition in adult and old mice, with effects that depended on thymus status and season. In adult mice with an intact thymus, Epithalamin increased stromal precursor cells in summer, and the overall effects of pineal factors appeared adaptive and thymus-dependent, while in old mice the effects were less pronounced.

Abstract

The role of the thymus in the influence of pineal gland on the number of stromal precursor cells to colonies of fibroblasts (CFU-F), progenitor cells to granulocyte-macrophage colonies (CFU-GM), CD3+, CD4+ and CD8+ cells in the bone marrow of adult and old mice CBA/Ca was investigated. False-operated and thymusectomized mice were injected Melatonin in the evening (spring season) or Epithalamin in the morning (summer and autumn). After the injection of Melatonin into adult mice the number of CFU-F and the value of the ratio CFU-F/CFU-GM decreased in false-operated animals, whereas the same indicators increased in thymusectomized animals. Under the influence of Melatonin, the ratio of CD4+/CD8+ cells increased in mice with an intact thymus and reduced in mice with a removed gland by increasing the number of CD8+ cells. The injection of Epithalamin led to the increasing in the number of CFU-F in summer, but did not lead to that in the autumn; the effect diminished in mice with a removed thymus. The orientation of changes of the indices under the influence of the pineal gland's factor in adult mice with an intact thymus corresponds to their seasonal fluctuations. After the injection of Melatonin into old mice CFU-F/CFU-GM ratio slightly reduced in false-operated animals and did not change in thymusectomized ones. Under the influence of melatonin the CD4+/CD8+ ratio of cells slightly increased in old mice with and without the thymus. Thus, the influence of the pineal gland' factors (Melatonin, Epithalamin) on the cellular structure of bone marrow, first of all on the cells of the microenvironment, in adult mice has an adaptive character and is realized with the participation of the thymus. In old mice, the thymus is also involved in the action of Melatonin on bone marrow, but the effect is less pronounced and is manifested mainly through changes in amount of CFU-GM.

Authors

Labunets, I F; Rodnichenko, A E; Butenko, G M