Influence of in vitro and in vivo insulin treatment on the hormone (histamine, serotonin, endorphin and triiodothyronine) content of thymus and spleen cells

The Immunoendocrine Thymus as a Pacemaker of Lifespan

The thymus develops from an endocrine area of the foregut, and retains the ancient potencies of this region. However, later it is populated by bone marrow originated lymphatic elements and forms a combined organ, which is a central part of the immune system as well as an influential element of the endocrine orchestra. Thymus produces self-hormones (thymulin, thymosin, thymopentin, and thymus humoral factor), which are participating in the regulation of immune cell transformation and selection, and also synthesizes hormones similar to that of the other endocrine glands such as melatonin, neuropeptides, and insulin, which are transported by the immune cells to the sites of requests (packed transport). Thymic (epithelial and immune) cells also have receptors for hormones which regulate them. This combined organ, which is continuously changing from birth to senescence seems to be a pacemaker of life. This function is basically regulated by the selection of self-responsive thymocytes as their complete destruction helps the development (up to puberty) and their gradual release in case of weakened control (after puberty) causes the erosion of cells and intercellular material, named aging. This means that during aging, self-destructive and non-protective immune activities are manifested under the guidance of the involuting thymus, causing the continuous irritation of cells and organs. Possibly the pineal body is the main regulator of the pacemaker, the neonatal removal of which results in atrophy of thymus and wasting disease and its later corrosion causes the insufficiency of thymus. The co-involution of pineal and thymus could determine the aging and the time of death without external intervention; however, external factors can negatively influence both of them.

In vivo effect of insulin on the hormone production of immune cells in mice - gender differences

The immune cells of rat and man synthesize, store and secrete hormones, characteristic to the endocrine glands. In the present experiments female and male CD1 mice were treated with 10 IU/kg insulin sc. (the controls with normal saline) and after 30 min peritoneal fluid was gained. The cells of the peritoneal fluid (lymphocytes and the monocyte-granulocyte group) were studied by immunocytochemical flow-cytometry to adrenocorticotropic hormone (ACTH), triiodothyronine (T3), histamine and serotonin content. In the female mice each hormone level was significantly lower in the insulin-treated animals, except histamine in the monocyte-granulocyte group. In the insulin-treated male animals, the hormone levels were similar to the control. The results 1) support the previously hypothesized hormonal network in the immune system, 2) justify that the insulin effect is not species dependent and 3) call attention to the sex, species and organ differences in the response.

Hormones in the immune system and their possible role. A critical review

Immune cells synthesize, store and secrete hormones, which are identical with the hormones of the endocrine glands. These are: the POMC hormones (ACTH, endorphin), the thyroid system hormones (TRH, TSH, T3), growth hormone (GH), prolactin, melatonin, histamine, serotonin, catecholamines, GnRH, LHRH, hCG, renin, VIP, ANG II. This means that the immune cells contain all of the hormones, which were searched at all and they also have receptors for these hormones. From this point of view the immune cells are similar to the unicells (Tetrahymena), so it can be supposed that these cells retained the properties characteristic at a low level of phylogeny while other cells during the evolution accumulated to form endocrine glands. In contrast to the glandular endocrine cells, immune cells are polyproducers and polyreceivers. As they are mobile cells, they are able to transport the stored hormone to different places (packed transport) or attracted by local factors, accumulate in the neighborhood of the target, synthesizing and secreting hormones locally. This is taking place, e.g. in the case of endorphin, where the accumulating immune cells calms pain caused by the inflammation. The targeted packed transport is more economical than the hormone-pouring to the blood circulation of glandular endocrines and the targeting also cares the other receptor-bearing cells timely not needed the effect. Mostly the immune-effects of immune-cell derived hormones were studied (except endorphin), however, it is not exactly cleared, while the system could have scarcely studied important roles in other cases. The evolutionary aspects and the known as well, as possible roles of immune-endocrine system and their hormones are listed and discussed.

[The immuno-endocrine system. A new endocrine theory: the problem of the packed transport]

Since the eighties of the last century hormone content was justified in immune cells (lymphocytes, granulocytes, monocytes, macrophages and mast cells), which produce, store and secrete these hormones. Although the amount of these materials in immune cells is relatively small, the mass of the producers (immune cells) is so large, that the phenomenon must be considered from endocrinological point of view, underlying the important differences between the "classical" and immuno-endocrine systems. Cells of the classic (built-in) endocrine system are mono-producers, while immune cells can synthesize many types of hormones (polyproducers). In addition, these cells can transport the whole hormone-producing machinery to the site of need, producing a local effect. This can be observed, for example, in the case of endorphin producing immune cells during inflammation and during early pregnancy around the chorionic villi. Hormone producing immune cells also have receptors for many hormones, so that they are poly-receivers. Via hormone producing and receiving capacity there is a bidirectional connection between the neuro-endocrine and immuno-endocrine systems. In addition, there is a network inside the immuno-endocrine system. The packed transport theory attempts to explain the mechanism and importance of the immuno-endocrine system.

Decreased hormone content of immune cells in children during acute lymphocytic leukemia (ALL) - effect of treatment

Histamine, serotonin and triiodothyronine (T3) content of different circulating lymphocyte subsets of leukemic (acute lymphocytic leukemia, ALL) and non-leukemic (control) children were investigated by multicolor flow cytometry. The hormone contents of the cells were followed from the time of diagnosis till the end of treatment. Each hormone could be detected in every time in the investigated cell types, although the amounts of them changed during the treatment.T lymphocytes: Significantly lower amount of serotonin was found in each T cell subsets (Th, Tc and activated T lymphocytes) of leukemic children compared to the healthy control group at the time of diagnosis and it was permanently low during the maintenance therapy. The decreased amount of serotonin could be demonstrated in Tc and Th cells even at one year after the end of treatment. However, there was no alteration in the histamine and T3 content of T cell subsets in the time of diagnosis, but significant decrease was detected during the maintenance therapy and after treatment.NK cells: The serotonin and T3 contents of NK cells (both NK and NKT subsets) were significantly lower at the time of diagnosis and during the maintenance therapy. Similar decrease was detected in the case of serotonin in B cells. Although there was no difference in the T3 content of B cells at the time of diagnosis, significantly lower amounts could be detected during the therapy compared to the healthy control group. The serotonin concentration remained low for years after the end of treatment, both in B and NK cells. These observations might have diagnostic and prognostic importance.

Endogenous opiates and behavior: 2006

This paper is the 29th consecutive installment of the annual review of research concerning the endogenous opioid system, now spanning 30 years of research. It summarizes papers published during 2006 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurological disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17).