Influence of Growth Hormone on Thymic Endocrine Activity in Humans

Mocchegiani, Eugenio; Paolucci, Paolo; Balsamo, Antonio; Cacciari, E; Fabris, Ν.

doi:10.1159/000181528

Cited by 53 publications

(21 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The secretion of thymulin, a chemically defined thymic hormone produced by TEC, is up-regulated by GH in different species, including mouse (7), dog (8), and man (9,10). GH also increases TEC proliferation in vitro as well as the expression of extracellular matrix ligands and receptors with consequent modulation of extracellular matrix-mediated TEC/thymocyte interactions (9,11).…”

mentioning

confidence: 99%

Growth Hormone and Its Receptor Are Expressed in Human Thymic Cells

Coelho¹

1998

Endocrinology

View full text Add to dashboard Cite

GH has been shown to modulate various functions of the thymus. We now demonstrate the production of human GH (hGH) by human thymic cells, and the expression of GH receptors in thymic epithelial cells (TEC) and in thymocytes at different stages of differentiation. The presence of hGH messenger RNA was shown by RT-PCR in both human thymocytes and in primary cultures of TEC. Moreover, immunoreactive hGH material was detected in culture media of thymocytes and TEC with the use of a sensitive immunoradiometric assay. GH receptor gene expression was shown in TEC in primary cultures and in fetal and postnatal TEC lines as well as in thymocytes. By immunocytochemistry, the presence of GH receptors in the various TEC preparations was confirmed. In cytofluorometric studies with the use of a biotinylated anti-GH receptor monoclonal antibody, we could show that GH receptors are predominantly expressed by immature thymocytes: over 90% of CD3ϩ cells (a phenotype characterizing the most immature T cell progenitors in the thymus) were GH receptor positive. Our results provide a molecular basis for an autocrine/paracrine mode of action of GH in the human thymus. (Endocrinology 139: [3837][3838][3839][3840][3841][3842] 1998)

show abstract

mentioning

confidence: 99%

Growth Hormone and Its Receptor Are Expressed in Human Thymic Cells

Coelho¹

1998

Endocrinology

View full text Add to dashboard Cite

show abstract

“…The subcapsular-perivascular region, demarcated by the Type 1 epithelium, is arguably one of the most important in the thymus, as it initiates thymopoiesis and produces most, ifnot all, of the known thymic hormones (18). In this respect, it was interesting to find that plasma thymulin levels were decreased in GHdeficient boys and that a single GH dose restored plasma thymulin levels (19).…”

Section: Discussionmentioning

confidence: 99%

Detection of growth hormone-producing cells in human thymus by immunohistochemistry and non-radioactive in situ hybridization.

Maggiano¹,

Piantelli²,

Ricci³

et al. 1994

J Histochem Cytochem.

View full text Add to dashboard Cite

It is well recognized that growth hormone (GH) may act as a growth and differentiation factor for the thymus gland. Recently, it has been reported that Pit-1/GHF-1 transcription factor, which controls the expression of both GH and prolactin, is expressed in stromal (not lymphoid) cells of human thymus. Here, we demonstrated by immunohistochemistry and in situ hybridization the presence of distinct GH-producing epithelial cell subsets in human thymus. The cells positive for GH mRNA and GH-immunoreactive substance are both located in the same thymus compartments, i.e., along the thymus capsule, in the subcapsular cortex, and within the septa. Local concentration of GH higher than systemic ones, in combination with other factors, may be important in regulating the thymic microenvironment necessary for T-lymphocyte differentiation.

show abstract

“…Argentina). Upon receipt the animals were housed in our own facilities in conventional conditions at 22 At the end of treatment animals were killed by decapitation and trunk blood was collected; serum was obtained and samples were stored at -2 0 °C until hormone assays.…”

Section: Animals and Experimental Designmentioning

confidence: 99%

Effects of Growth Hormone and Thyroxine on Thymulin Secretion in Aging Rats

Goya

Sosa²,

Bevilacqua³

et al. 1993

Neuroendocrinology

View full text Add to dashboard Cite

It is well-established that the activity of the endocrine thymus is under neuroendocrine control. In particular, growth hormone (GH) and thyroxine (T₄) have been shown to be capable of reconstituting thymus function in hormone-deficient animals. It was therefore of interest to assess the effect of combined administration of ovine GH (0.1 mg/100 g BW/day) and T₄ (10 µg/100 g BW/ day) on serum thymulin levels in young (5 months), old (21 months) and senescent (29-30 months) male Sprague-Dawley rats. Age-matched controls received 0.1 mg bovine serum albumin/100 g BW daily during the same period (14 days). Prolactin (Prl), GH, T₄ and triiodothyronine (T₃) were measured in serum by radioimmunoassay, whereas serum thymulin was determined by rosette bioassay. As expected, GH and T₄ were lower in the old and senescent controls whereas serum Prl displayed a slight age-related increase. No age changes were detected in serum T3. Hormone-treated animals showed supra-physiologic levels of both T4 and T3, but serum levels were comparable among the three treated age groups for each thyroid hormone. Endogenous GH levels were moderately elevated in the treated rats. In the control rats serum thymulin showed a marked reduction from 5 to 21 months of age but no further reduction was observed between 21 and 29-30 months. Hormone treatment induced a mean relative increase (% increase relative to age-matched controls) in serum thymulin of 44, 38 and 48% in young, old and senescent rats, respectively. Despite this stimulation, thymulin levels in the old and senescent treated groups were still significantly lower than the corresponding values in the young controls. It is concluded that (a) the activity of the endocrine thymus declines with age in male rats, and (b) in relative terms, aged rats possess a preserved capacity to increase thymulin secretion in response to combined administration of GH and T₄.

show abstract

Influence of Growth Hormone on Thymic Endocrine Activity in Humans

Cited by 53 publications

References 26 publications

Growth Hormone and Its Receptor Are Expressed in Human Thymic Cells

Growth Hormone and Its Receptor Are Expressed in Human Thymic Cells

Detection of growth hormone-producing cells in human thymus by immunohistochemistry and non-radioactive in situ hybridization.

Effects of Growth Hormone and Thyroxine on Thymulin Secretion in Aging Rats

Contact Info

Product

Resources

About