Endocrine Abstracts

Neuroimmunoendocrine changes of the pineal and thymic function, are now believed to pay an important role in the mechanisms of age-associated diseases development. Here we studied the morphofunctional and signal molecules unity of pineal gland and thymus during ageing. Autopsic pineal gland and thymus material sampled from people was divided into groups 1 – middle-aged people (60–74 years) and 2 – old people (75–89 years). Ultra-thin slices were used for electron microscopy. The study was carried out on the electron microscope JEM-100S. The identification of markers of signal molecules serotonin, melatonin, CD8, CD20 was carried out with immunohistochemical method using primary mouse MABs, and secondary antibodies, biotinylated anti-mouse immunoglobulins. The data of electronic microscopy had shown the ultrastructure similarity of pinealocytes and thymic epithelial cells (TEC) in autopsy samples of pineal gland and thymus. Pinealocytes and TEC have the high number of round vesicules with, as we suppose, can consist biological activity signal molecules, in pinealocytes and TEC cytoplasm. These data can show that the both types of cells can belong to neuroimmunoendocrine system. By immunohistochemical method it was verified the expression of common signal molecules – endocrine cells markers (melatonin, serotonin) and lymphocytes (CD8, CD20) in the human pineal gland and thymus. The expression of melatonin, serotonin, CD8, CD20 in the pineal gland and thymus decreased during aging.

Thus, the melatonin, serotonin CD8, CD20 expression in the pinealocytes and thymic cells confirms the unity of pineal gland and thymus as an neuroimmunoendocrine organs.