Growth hormone deficiency pathophysiology: Difference between revisions

Jump to navigation Jump to search
No edit summary
No edit summary
Line 45: Line 45:
* STAT proteins 1 and 5 may also interact more directly with the GH receptor molecule [32]. STAT 5 plays important roles in the regulation of expression and in the sexually dimorphic expression of some liver genes.  
* STAT proteins 1 and 5 may also interact more directly with the GH receptor molecule [32]. STAT 5 plays important roles in the regulation of expression and in the sexually dimorphic expression of some liver genes.  
* a defect in GH-mediated JAK-STAT signal transduction could be a cause of the GH resistance that develops in the KD state and in this way contribute to the striking growth retardation that develops in this condition. In rats with chronic renal failure, a condition of acquired growth failure associated with GH resistance, we recently demonstrated that hepatic GH-dependent JAK-STAT signaling is impaired (22).  
* a defect in GH-mediated JAK-STAT signal transduction could be a cause of the GH resistance that develops in the KD state and in this way contribute to the striking growth retardation that develops in this condition. In rats with chronic renal failure, a condition of acquired growth failure associated with GH resistance, we recently demonstrated that hepatic GH-dependent JAK-STAT signaling is impaired (22).  
[[File:Growth Hormone-pathway1.gif|500px|center|thumb|GH signaling]]


==Genetic basis of growth hormone deficiency==
==Genetic basis of growth hormone deficiency==
==== ''[[POU1F1]]'' gene mutations ====
==== ''[[POU1F1]]'' gene mutations ====
* It is the most common known genetic cause of the combined [[Pituitary gland|pituitary]] hormone deficiency.<ref name="pmid26608600">{{cite journal| author=Ziemnicka K, Budny B, Drobnik K, Baszko-Błaszyk D, Stajgis M, Katulska K et al.| title=Two coexisting heterozygous frameshift mutations in PROP1 are responsible for a different phenotype of combined pituitary hormone deficiency. | journal=J Appl Genet | year= 2016 | volume= 57 | issue= 3 | pages= 373-81 | pmid=26608600 | doi=10.1007/s13353-015-0328-z | pmc=4963446 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=26608600  }}</ref>
* It is the most common known genetic cause of the combined [[Pituitary gland|pituitary]] hormone deficiency.<ref name="pmid26608600">{{cite journal| author=Ziemnicka K, Budny B, Drobnik K, Baszko-Błaszyk D, Stajgis M, Katulska K et al.| title=Two coexisting heterozygous frameshift mutations in PROP1 are responsible for a different phenotype of combined pituitary hormone deficiency. | journal=J Appl Genet | year= 2016 | volume= 57 | issue= 3 | pages= 373-81 | pmid=26608600 | doi=10.1007/s13353-015-0328-z | pmc=4963446 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=26608600  }}</ref>

Revision as of 16:02, 29 September 2017

Growth hormone deficiency Microchapters

Home

Patient Information

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Growth hormone deficiency from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

Diagnostic Criteria

History and Symptoms

Physical Examination

Laboratory Findings

X Ray

CT

MRI

Echocardiography or Ultrasound

Other Imaging Findings

Other Diagnostic Studies

Treatment

Medical Therapy

Surgery

Primary Prevention

Secondary Prevention

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Case Studies

Case #1

Growth hormone deficiency pathophysiology On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Growth hormone deficiency pathophysiology

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Growth hormone deficiency pathophysiology

CDC on Growth hormone deficiency pathophysiology

Growth hormone deficiency pathophysiology in the news

Blogs on Growth hormone deficiency pathophysiology

Directions to Hospitals Treating Growth hormone deficiency

Risk calculators and risk factors for Growth hormone deficiency pathophysiology

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Mohammed Abdelwahed M.D[2]

Overview

The somatotroph cells of the anterior pituitary gland produce growth hormone (GH). GH best-known effect is increasing body mass. GH causes epiphyseal plate widening and cartilage growth. GH deficiency results in alterations in the physiology of different systems of the body, manifesting as altered lipid metabolism, increased subcutaneous visceral fat, decreased muscle mass. Genetic basis of congenital growth hormone deficiency depends on many genes, for example, POU1F1 gene mutations are the most common known genetic cause of the combined pituitary hormone deficiency. Gene deletions, frameshift mutations, and nonsense mutations of GH1 gene have been described as causes of familial GHD.

Pathophysiology

  • GH deficiency results in alterations in the physiology of different systems of the body, manifesting as altered lipid metabolism, increased subcutaneous visceral fat, decreased muscle mass, decreased bone density, low exercise performance, and reduced quality of life.

Regulation of growth hormone secretion

Growth hormone secretion regulations, source: By OpenStax College - Anatomy & Physiology, Connexions Web site. httpcnx.orgcontentcol114961.6, Jun 19, 2013., CC BY 3.0, httpscommons.wikimedia.orgwindex.phpcurid=30148146

Molecular effects of growth hormone on cells

  • GH stimulated cell proliferation in both trabecular and stromal osteoblasts.
  • Human trabecular osteoblasts produce mainly IGF-II, IGFBP-3 and fewer quantities of IGF-I in culture.
  • IGFs and their binding proteins may exert important regulatory effects on the biological effects of GH on human osteoblasts.
  • Growth hormone (GH) acts by binding to a specific receptor homodimer, located mostly in the liver.
  • The receptor consists of an extracellular ligand-binding domain, a single membrane-spanning domain, and a cytoplasmic signaling component.
  • Its predominant action is to stimulate hepatic synthesis and secretion of insulin-like growth factor-1 (IGF-1), a potent growth and differentiation factor [1].
  • IGF-1 is a critical protein induced by GH and is likely responsible for most of the growth-promoting activities of GH [33].
  • IGF-1 also directly inhibits GH secretion [33] and GH receptor function [34] by a negative feedback regulation loop.
Growth hormone peripheral action, source: By Mikael Häggström.When using this image in external works, it may be cited asHäggström, Mikael (2014). Medical gallery of Mikael Häggström 2014. WikiJournal of Medicine 1 (2). DOI10.15347wjm2014.008. ISSN 2002-4436
  • A single GH molecule complexes with two GH receptor molecules, followed by rapid internal rotation, and activation of JAK2 tyrosine kinase, leading to phosphorylation of several cytoplasmic signaling molecules determining cell proliferation and differentiated function.
  • Activation of Jak2 leads to mitogenic proliferation, phosphorylation of intracellular proteins, MAP kinase activation, activation of Stats 1, 3, and 5, and induction of target gene expression.
  • The STAT proteins comprise important signaling components for GH action.
  • These cytoplasmic proteins are phosphorylated by JAK2 and directly translocated to the cell nucleus, where they elicit GH-specific target gene effects by binding to nuclear DNA. [1].
  • STAT proteins 1 and 5 may also interact more directly with the GH receptor molecule [32]. STAT 5 plays important roles in the regulation of expression and in the sexually dimorphic expression of some liver genes.
  • a defect in GH-mediated JAK-STAT signal transduction could be a cause of the GH resistance that develops in the KD state and in this way contribute to the striking growth retardation that develops in this condition. In rats with chronic renal failure, a condition of acquired growth failure associated with GH resistance, we recently demonstrated that hepatic GH-dependent JAK-STAT signaling is impaired (22).
GH signaling

Genetic basis of growth hormone deficiency

POU1F1 gene mutations

GH1 gene mutations

Syndrome of bioinactive GH

GH receptor signal transduction

  • It is essential for normal signaling of the GH receptor. Mutations in the gene encoding signal transducer decrease the response of receptors to GH.[8]

IGF-I gene mutations

Defective stabilization of circulating IGF-I

  • Acid-labile subunit is important for the stabilization of the IGF-I.
  • Mutations in the gene coding for it causes less stable and subsequently less effect.[10]

IGF-I receptor mutations

References

  1. Cuttler L (1996). "The regulation of growth hormone secretion". Endocrinol Metab Clin North Am. 25 (3): 541–71. PMID 8879986.
  2. MURPHY WR, DAUGHADAY WH, HARTNETT C (1956). "The effect of hypophysectomy and growth hormone on the incorporation of labeled sulfate into tibial epiphyseal and nasal cartilage of the rat". J Lab Clin Med. 47 (5): 715–22. PMID 13319878.
  3. Veldhuis JD, Roemmich JN, Richmond EJ, Rogol AD, Lovejoy JC, Sheffield-Moore M; et al. (2005). "Endocrine control of body composition in infancy, childhood, and puberty". Endocr Rev. 26 (1): 114–46. doi:10.1210/er.2003-0038. PMID 15689575.
  4. Ziemnicka K, Budny B, Drobnik K, Baszko-Błaszyk D, Stajgis M, Katulska K; et al. (2016). "Two coexisting heterozygous frameshift mutations in PROP1 are responsible for a different phenotype of combined pituitary hormone deficiency". J Appl Genet. 57 (3): 373–81. doi:10.1007/s13353-015-0328-z. PMC 4963446. PMID 26608600.
  5. Li S, Crenshaw EB, Rawson EJ, Simmons DM, Swanson LW, Rosenfeld MG (1990). "Dwarf locus mutants lacking three pituitary cell types result from mutations in the POU-domain gene pit-1". Nature. 347 (6293): 528–33. doi:10.1038/347528a0. PMID 1977085.
  6. Wu W, Cogan JD, Pfäffle RW, Dasen JS, Frisch H, O'Connell SM; et al. (1998). "Mutations in PROP1 cause familial combined pituitary hormone deficiency". Nat Genet. 18 (2): 147–9. doi:10.1038/ng0298-147. PMID 9462743.
  7. Besson A, Salemi S, Deladoëy J, Vuissoz JM, Eblé A, Bidlingmaier M; et al. (2005). "Short stature caused by a biologically inactive mutant growth hormone (GH-C53S)". J Clin Endocrinol Metab. 90 (5): 2493–9. doi:10.1210/jc.2004-1838. PMID 15713716.
  8. Hwa V, Camacho-Hübner C, Little BM, David A, Metherell LA, El-Khatib N; et al. (2007). "Growth hormone insensitivity and severe short stature in siblings: a novel mutation at the exon 13-intron 13 junction of the STAT5b gene". Horm Res. 68 (5): 218–24. doi:10.1159/000101334. PMID 17389811.
  9. Batey L, Moon JE, Yu Y, Wu B, Hirschhorn JN, Shen Y; et al. (2014). "A novel deletion of IGF1 in a patient with idiopathic short stature provides insight Into IGF1 haploinsufficiency". J Clin Endocrinol Metab. 99 (1): E153–9. doi:10.1210/jc.2013-3106. PMC 3879666. PMID 24243634.
  10. Domené HM, Hwa V, Argente J, Wit JM, Wit JM, Camacho-Hübner C; et al. (2009). "Human acid-labile subunit deficiency: clinical, endocrine and metabolic consequences". Horm Res. 72 (3): 129–41. doi:10.1159/000232486. PMID 19729943.
  11. Kawashima Y, Higaki K, Fukushima T, Hakuno F, Nagaishi J, Hanaki K; et al. (2012). "Novel missense mutation in the IGF-I receptor L2 domain results in intrauterine and postnatal growth retardation". Clin Endocrinol (Oxf). 77 (2): 246–54. doi:10.1111/j.1365-2265.2012.04357.x. PMID 22309212.