Linked Life Data

20938222

Source:http://linkedlifedata.com/resource/pubmed/id/20938222

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7 Suppl
pubmed:dateCreated
2010-10-12
pubmed:abstractText
IGF-I and PTH have synergistic actions on bone and some effects of the anabolic actions of PTH are mediated by local production of IGF-I, as has been shown in vitro and in vivo studies both in animals and humans. PTH can induce skeletal IGF-I expression both in vitro and in vivo. In chondrocytes, IGF-I synthesis is under GH control, whereas in osteoblasts its synthesis is fundamentally under the control of PTH. PTH stimulates the synthesis of IGF-I via a cAMP-dependent mechanism, and this factor has pro-differentiating and prosurvival effects on osteoblasts. In in vitro studies, IGF-I and PTH have shown a synergistic action on the osteoblasts of bone marrow. Human clinical data confirm the interactions between PTH and GH-IGF-I axis on bone. PTH is involved in the development of osteoporosis in adult patients with GH deficiency (GHD). In fact, patients with GHD show renal, skeletal, and intestinal cell insensitivity to PTH, leading to a mild state of PTH resistance and increased serum PTH levels. In addition, GH replacement in these patients restores PTH secretory rhythm, increases bone turnover markers, 1,25-dihydroxy vitamin D concentration, and Ca absorption/reabsorption, thus contributing to the positive effects of GH on bone. On the other hand, in post-menopausal women with primary hyperparathyroidism a reduced secretion of GH is observed, in association with a greater impairment of bone mass. GH administration resulted in increased IGF-I concentration, decreased PTH concentration, and increased nephrogenous cAMP. In conclusion, the anabolic action of PTH requires paracrine and autocrine effects of IGF-I.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0391-4097
pubmed:author
pubmed:issnType
Print
pubmed:volume
33
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
22-6
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Role of IGF-I on PTH effects on bone.
pubmed:affiliation
Department of Molecular and Clinical Endocrinology and Oncology, Federico II University of Naples, Via S. Pansini 5, Naples, Italy. gaelomba@unina.it
pubmed:publicationType
Journal Article, Review