ISSN:1663-2818    

DOI:10.1159/000184750

出版商:S. Karger AG    

年代:1996

数据来源: Karger

ISSN:1663-2818    

DOI:10.1159/000184751

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Growth hormone (GH)-deficient mice exhibit a microcephalic cerebrum with hypomyelination, retarded neuronal growth with poor synaptogenesis, and reduced levels of spontaneous locomotion activity with an indistinct diurnal periodicity. The hypomyelination is found to be due to arrested glial proliferation, suggesting that the action of GH on the proliferation and maturation of both glial and neuronal cells is a necessary precondition of myelin formation, apart from the complementary or synergistic actions of T4. In contrast, the cerebral hypomyelination in hypothyroid mice is not related to arrested glial proliferation, demonstrating that thyroid hormones can act independently on myelinogenesis. On the other hand, the activity of sn-glycerol-3-phosphate dehydrogenase is significantly depressed in hypothyroid cerebella, suggesting that T4 is indistinguishable for the maturation of Bergmann glial cells. In addition, the developmental expression of hippocalcin in the GH-deficient brain is retarded, suggesting the poor maturation of the neuronal network, because hippocalcin is considered to associate in postsynaptic neural functions and in synaptic plasticity.

ISSN:1663-2818    

DOI:10.1159/000184752

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

During the past few years, there has been increasing interest in functions that growth hormone (GH) may play in the central nervous system. Accumulating evidence that the hormone may pass the blood-brain barrier and the psychological improvements seen in adults following GH therapy have received particular attention. This paper will review our recent studies on GH receptors in the human and rat brain. A recent study on the effects of GH treatment in adult growth hormone-deficient patients on quality of life and cerebrospinal fluid levels of various hormones and neurotransmitters is also included.

ISSN:1663-2818    

DOI:10.1159/000184753

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

The interactions among short stature, growth hormone (GH) and cognitive functions have been extensively studied so far. However, although it seems well established that short stature is associated with cognitive problems, little effort has been made to point out the presence of specific psychological effects related to the different forms of short stature. In ‘short normal’ children, the presence of a scholastic underachievement seems to suggest that short stature ‘itself might predispose these patients to some of their psychosocial difficulties. The higher incidence of academic failure, in presence of a normal intellectual functioning, has been attributed to environmental and psychosocial factors, including over-protective parents and low self-esteem resulting from the impact of short stature. These problems appear to be common also to other forms of short stature (such as Turner’s syndrome) where, however, they are frequently associated with other specific deficits. The in vivo model which might allow, at least in part, better understanding of GH (per se)-dependent effects is represented by GH deficiency (GHD), in which, however, the specific role of GH on psychological functioning is frequently masked by the presence of associated hormonal deficiencies. Children with isolated GHD are reported to have specific educational deficits, in particular learning disability and attention-deficit disorders, which have been tentatively attributed to a compromised intellectual potential. The psychological effects of long-term GH treatment in children with GHD still remain controversial, with some retrospective studies describing a generally beneficial outcome. Since early experiences in school are closely related to success in adult life, the possible implications that GHD during childhood holds during adulthood have been recently considered. Although regional differences have been observed in subgroups of adults with GHD, it seems that these patients have normal cognitive functions and educational attainment, but are more likely to be unemployed (and unmanned) than members of the general population. In general, patients with GHD, who have been treated at centers where psychological counselling was an integral part of the treatment program, seem to be better adjusted in adult life. For these reasons, a multidisciplinary treatment approach could allow early detection of problems in academic achievement and psychosocial development in patients with short stature, being immediately able to provide the appropriate educational and counselling interv

ISSN:1663-2818    

DOI:10.1159/000184754

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Children referred for growth hormone (GH) treatment have increased school achievement problems, lack appropriate social skills and show several forms of behavior problems. A multicenter study in the United States has revealed that many GH-impaired children exhibit a cluster of behavioral symptoms involving disorders of mood and attention. Anxiety, depression, somatic complaints and attention deficits have been identified. These symptoms decline in frequency over a period of 3 years, beginning shortly after GH replacement therapy is started. Many of the patients who have received GH and had good growth responses show lower than average quality of life in young adulthood after treatment is completed. GH-deficient adults placed on GH therapy report improvement in psychological well-being and health status, suggesting that GH might have a central neuroendocrine action. Among a group of adults who were GH deficient as children, we find a high incidence of social phobia, a psychiatric disorder linked to GH secretion and usually accompanied by poor life quality. An ongoing study of non-GH-deficient short individuals suggests that short stature is not the cause of this outcome. We conclude that the origins of psychiatric comorbidities, such as social phobia and depression, in GH deficient adults are likely to be neuroendocrine as well as psychosocial.

ISSN:1663-2818    

DOI:10.1159/000184755

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Quality of life research in adults with growth hormone deficiency (GHD) is a developing field. It has been recognised that adults with childhood onset GHD suffer social and psychological disadvantages. The effects of GHD of adult onset have only been shown relatively recently. Assessment of these patients, using measures of physical and psychological well-being, has demonstrated that adults with GHD perceive themselves as much less healthy compared with matched controls. The majority of studies investigating the effects of growth hormone replacement therapy indicate that quality of life improves with treatment, although this is not a consistent finding.

ISSN:1663-2818    

DOI:10.1159/000184756

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Hypocellularity of primary lymphoid organs is a distinctive and reproducible characteristic of aged humans and animals. Similar changes have been reported in both hypophysectomized and dwarf rodents. In the bone marrow of these animals, there is an associated reduction in the number of erythroid, lymphoid and myeloid elements. Implantation of growth hormone (GH)-secreting GH3 pituitary cells or infusion of growth hormone into aged rodents dramatically improves cellularity of both the thymus gland and bone marrow. At present it is unknown whether these effects are due to direct effects of growth hormone on hematopoietic cells or if they are caused by the induction of insulin-like growth factor-1 (IGF-1) synthesis. We recently discovered that colony-stimulating factor-1 (CSF-1) and interleukin-3 (IL-3) induce expression and synthesis of the IGF-1 peptide in murine bone marrow cells. Transcripts for IGF-1 increase approximately 50-fold during differentiation over the negligible levels that are expressed in freshly isolated bone marrow cells. Two potential functions of macrophage-derived IGF-1 are to: (a) increase the proliferation of early or committed bone marrow progenitors and (b) reduce their rate of cell death. In support of the first possibility, IGF binding protein-3 significantly inhibits the proliferation of CSF-1-treated bone marrow cells and this inhibition can be reversed by addition of exogenous IGF-1. In support of the second possibility, we have induced apoptosis of both nonadherent bone marrow cells and a myeloid progenitor cell line by depriving these cells of CSFs. Preliminary results indicate that addition of IGF-1 to these cells reduces apoptotic cell death by 50%. These data establish that two different CSFs, CSF-1 and IL-3, induce abundant expression of IGF-1 as these cells differentiate into more mature hematopoietic cells. This model offers a novel approach for investigating the developmental expression of IGF-1 during defined differentiation pathways of hematopoietic cells. If IGF-1 is indeed proven to act as a survival factor for hematopoietic progenitors, these data would support the idea that the hypocellularity of primary lymphoid tissues in aged animals is related to the limited availability to these cells of either growth hormone or IGF-1.

ISSN:1663-2818    

DOI:10.1159/000184757

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Elderly individuals have four to five times the case rate of cancer, tuberculosis and herpes zoster and six to seven times the fatality rate from pneumonia compared to young adults. This may be causally related to two changes that occur with aging, i.e. decreased growth hormone (GH)/insulin-like growth factor-1 (IGF-1) production and decreased immune function. Data from our laboratory as well as others have shown that, based on either GH secretory dynamics or IGF-1 levels, approximately 40% of adults aged 60 and older are GH deficient. In the same population of subjects, immune function decreases such that there is a decline in cell-mediated and humoral immune responsiveness. Some of these immune deficits have been shown to be reversed in humans and primates by GH and/or IGF-1 treatment. This paper will review some of these data.

ISSN:1663-2818    

DOI:10.1159/000184758

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Growth hormone (GH) and insulin-like growth factor 1 (IGF-1), especially the former, have immunoregulatory effects in addition to anabolic effects. The hormones may act to protect the host from lethal bacterial infection by promoting the maturation of myeloid cells, stimulating phagocyte migration, priming phagocytes for the production of superoxide anions and cytokines, and enhancing opsonic activity. GH administration may be beneficial for the prevention, as well as treatment, of severe sepsis in critical illness.

ISSN:1663-2818    

DOI:10.1159/000184759

出版商:S. Karger AG    

年代:1996

数据来源: Karger