Hypogonadism pathophysiology: Difference between revisions
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==== Hypogonadism in males ==== | ==== Hypogonadism in males ==== | ||
* The hypogonadism pathogenesis in males depends mainly on the [[testosterone]] deficiency. [[Testosterone]] secretion occurs as the following: | * The hypogonadism pathogenesis in males depends mainly on the [[testosterone]] deficiency. [[Testosterone]] secretion occurs as the following: | ||
** Testosterone is secreted in response to stimulation from the [[ | ** Testosterone is secreted in response to stimulation from the [[cerebral cortex]] to the [[hypothalamus]]. The [[hypothalamus]] by its role secrets the [[Gonadotropin-releasing hormone|gonadotropin releasing hormones (GnRH)]]. | ||
** [[GnRH]] stimulates the [[pituitary gland]] which by its role secretes the [[Gonadotropin|gonadal hormones]] the [[Follicle Stimulating Hormone|Follicle Stimulating Hormone (FSH)]] and the [[Luteinizing hormone|Luteinizing Hormone (LH)]]. | ** [[GnRH]] stimulates the [[pituitary gland]] which by its role secretes the [[Gonadotropin|gonadal hormones]] the [[Follicle Stimulating Hormone|Follicle Stimulating Hormone (FSH)]] and the [[Luteinizing hormone|Luteinizing Hormone (LH)]]. | ||
** In males, [[LH]] stimulates the [[Leydig cells]] in the [[testes]] which produce [[testosterone]] by converting the [[cholesterol]] to testosterone. | ** In males, [[LH]] stimulates the [[Leydig cells]] in the [[testes]] which produce [[testosterone]] by converting the [[cholesterol]] to testosterone. | ||
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* [[Deafness|Unilateral deafness]] | * [[Deafness|Unilateral deafness]] | ||
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* | * FGFR1 gene has an organizational function with ANOS1. | ||
* Products of ANOS1 act like a co receptor for FGFR1.<ref name="pmid15548653">{{cite journal| author=González-Martínez D, Kim SH, Hu Y, Guimond S, Schofield J, Winyard P et al.| title=Anosmin-1 modulates fibroblast growth factor receptor 1 signaling in human gonadotropin-releasing hormone olfactory neuroblasts through a heparan sulfate-dependent mechanism. | journal=J Neurosci | year= 2004 | volume= 24 | issue= 46 | pages= 10384-92 | pmid=15548653 | doi=10.1523/JNEUROSCI.3400-04.2004 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15548653 }}</ref> | * Products of ANOS1 act like a co receptor for FGFR1.<ref name="pmid15548653">{{cite journal| author=González-Martínez D, Kim SH, Hu Y, Guimond S, Schofield J, Winyard P et al.| title=Anosmin-1 modulates fibroblast growth factor receptor 1 signaling in human gonadotropin-releasing hormone olfactory neuroblasts through a heparan sulfate-dependent mechanism. | journal=J Neurosci | year= 2004 | volume= 24 | issue= 46 | pages= 10384-92 | pmid=15548653 | doi=10.1523/JNEUROSCI.3400-04.2004 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15548653 }}</ref> | ||
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* | * PROK2 and PROKR2 has a role in the development of [[olfactory bulb]] and [[GnRH]] neurons migration.<ref name="pmid18559922">{{cite journal| author=Cole LW, Sidis Y, Zhang C, Quinton R, Plummer L, Pignatelli D et al.| title=Mutations in prokineticin 2 and prokineticin receptor 2 genes in human gonadotrophin-releasing hormone deficiency: molecular genetics and clinical spectrum. | journal=J Clin Endocrinol Metab | year= 2008 | volume= 93 | issue= 9 | pages= 3551-9 | pmid=18559922 | doi=10.1210/jc.2007-2654 | pmc=2567850 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=18559922 }}</ref> | ||
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Revision as of 19:24, 8 September 2017
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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Ahmed Elsaiey, MBBCH [2]
Overview
Hypogonadism pathophysiology depends mainly on the deficiency of the testosterone hormone. Testosterone is secreted in response to stimulation from the brain to the hypothalamus which secretes the gonadotropin releasing hormones (GnRH). GnRH is responsible for secretion of FSH and LH. In males, LH stimulates the leydig cells in the testes which produce testosterone by converting the cholesterol to testosterone. In females, FSH and LH stimulate secretion of estrogen which helps in follicles maturation. Estrogen also helps in the process of ovulation. Deficiency of GnRH leads to decrease of testosterone levels and eventually causing hypogonadism. Genetic mutations have a big role as well in the development of hypogonadism. There are more than 25 gene mutations participate in the pathogenesis of hypogonadism. These genes like genes responsible for Kallmann syndrome as ANOS 1, SOX10, SEMA3A, IL17RD and FEZF1. Other genes include KISS, GNRNH, and PROK.
Pathophysiology
Pathogenesis
Hypogonadism in males
- The hypogonadism pathogenesis in males depends mainly on the testosterone deficiency. Testosterone secretion occurs as the following:
- Testosterone is secreted in response to stimulation from the cerebral cortex to the hypothalamus. The hypothalamus by its role secrets the gonadotropin releasing hormones (GnRH).
- GnRH stimulates the pituitary gland which by its role secretes the gonadal hormones the Follicle Stimulating Hormone (FSH) and the Luteinizing Hormone (LH).
- In males, LH stimulates the Leydig cells in the testes which produce testosterone by converting the cholesterol to testosterone.
- Production of testosterone from the testes gives negative feed back to the pituitary. This feedback inhibits the production of FSH and LH from the pituitary.
- Testosterone deficiency can occur when different acquired or congenital disease affects the organs responsible for its secretion. So, pathogenesis of the hypogonadism in males depends on the underlying cause.[1]
- GnRH deficiency has the main role in hypogonadism pathogenesis in males as it leads to decrease production of the gonadal hormone and deficiency of testosterone eventually.[2]
- It has been proved that GnRH deficiency is associated with most cases of idiopathic hypogonadotropic hypogonadism in males.
Genetic
- Genetic mutations have a big role in the development of the hypogonadism especially congenital hypogonadotropic hypogonadism. There are more than 25 genes responsible for the pathogenesis of hypogonadism.[3]
- In this table number of genes with the associated diseases causing hypogonadism are enlisted:
| Associated disease | Genes | Mutation | Associated features with the mutated gene | Comments |
|---|---|---|---|---|
| Kallman syndrome (with loss of smelling sense - anosmia) | ANOS 1[4] |
|
| |
| SOX10 | ||||
| SEMA3A |
|
| ||
| IL17RD | ||||
| FEZF1 |
|
|||
| Idiopathic hypogonadotropic hypogonadism (IHH) (normal smelling sensation - normosmia) | KISS1R |
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| KISS1 |
|
|||
| GNRHR |
|
| ||
| GNRH1 |
| |||
| TAC3 |
| |||
| Mixed anosmic and nosmic IHH | FGFR1 |
|
| |
| FGF8[12] | ||||
| PROK2
PROKR2 |
|
References
- ↑ Kumar P, Kumar N, Thakur DS, Patidar A (2010). "Male hypogonadism: Symptoms and treatment". J Adv Pharm Technol Res. 1 (3): 297–301. doi:10.4103/0110-5558.72420. PMC 3255409. PMID 22247861.
- ↑ Spratt DI, Carr DB, Merriam GR, Scully RE, Rao PN, Crowley WF (1987). "The spectrum of abnormal patterns of gonadotropin-releasing hormone secretion in men with idiopathic hypogonadotropic hypogonadism: clinical and laboratory correlations". J Clin Endocrinol Metab. 64 (2): 283–91. doi:10.1210/jcem-64-2-283. PMID 3098771.
- ↑ Boehm U, Bouloux PM, Dattani MT, de Roux N, Dodé C, Dunkel L; et al. (2015). "Expert consensus document: European Consensus Statement on congenital hypogonadotropic hypogonadism--pathogenesis, diagnosis and treatment". Nat Rev Endocrinol. 11 (9): 547–64. doi:10.1038/nrendo.2015.112. PMID 26194704.
- ↑ Franco B, Guioli S, Pragliola A, Incerti B, Bardoni B, Tonlorenzi R; et al. (1991). "A gene deleted in Kallmann's syndrome shares homology with neural cell adhesion and axonal path-finding molecules". Nature. 353 (6344): 529–36. doi:10.1038/353529a0. PMID 1922361.
- ↑ Schwanzel-Fukuda M, Bick D, Pfaff DW (1989). "Luteinizing hormone-releasing hormone (LHRH)-expressing cells do not migrate normally in an inherited hypogonadal (Kallmann) syndrome". Brain Res Mol Brain Res. 6 (4): 311–26. PMID 2687610.
- ↑ Pingault V, Bodereau V, Baral V, Marcos S, Watanabe Y, Chaoui A; et al. (2013). "Loss-of-function mutations in SOX10 cause Kallmann syndrome with deafness". Am J Hum Genet. 92 (5): 707–24. doi:10.1016/j.ajhg.2013.03.024. PMC 3644631. PMID 23643381.
- ↑ Cariboni A, Davidson K, Rakic S, Maggi R, Parnavelas JG, Ruhrberg C (2011). "Defective gonadotropin-releasing hormone neuron migration in mice lacking SEMA3A signalling through NRP1 and NRP2: implications for the aetiology of hypogonadotropic hypogonadism". Hum Mol Genet. 20 (2): 336–44. doi:10.1093/hmg/ddq468. PMID 21059704.
- ↑ Teles MG, Bianco SD, Brito VN, Trarbach EB, Kuohung W, Xu S; et al. (2008). "A GPR54-activating mutation in a patient with central precocious puberty". N Engl J Med. 358 (7): 709–15. doi:10.1056/NEJMoa073443. PMC 2859966. PMID 18272894.
- ↑ Bouligand J, Ghervan C, Tello JA, Brailly-Tabard S, Salenave S, Chanson P; et al. (2009). "Isolated familial hypogonadotropic hypogonadism and a GNRH1 mutation". N Engl J Med. 360 (26): 2742–8. doi:10.1056/NEJMoa0900136. PMID 19535795.
- ↑ Gianetti E, Tusset C, Noel SD, Au MG, Dwyer AA, Hughes VA; et al. (2010). "TAC3/TACR3 mutations reveal preferential activation of gonadotropin-releasing hormone release by neurokinin B in neonatal life followed by reversal in adulthood". J Clin Endocrinol Metab. 95 (6): 2857–67. doi:10.1210/jc.2009-2320. PMC 2902066. PMID 20332248.
- ↑ González-Martínez D, Kim SH, Hu Y, Guimond S, Schofield J, Winyard P; et al. (2004). "Anosmin-1 modulates fibroblast growth factor receptor 1 signaling in human gonadotropin-releasing hormone olfactory neuroblasts through a heparan sulfate-dependent mechanism". J Neurosci. 24 (46): 10384–92. doi:10.1523/JNEUROSCI.3400-04.2004. PMID 15548653.
- ↑ Falardeau J, Chung WC, Beenken A, Raivio T, Plummer L, Sidis Y; et al. (2008). "Decreased FGF8 signaling causes deficiency of gonadotropin-releasing hormone in humans and mice". J Clin Invest. 118 (8): 2822–31. doi:10.1172/JCI34538. PMC 2441855. PMID 18596921.
- ↑ Cole LW, Sidis Y, Zhang C, Quinton R, Plummer L, Pignatelli D; et al. (2008). "Mutations in prokineticin 2 and prokineticin receptor 2 genes in human gonadotrophin-releasing hormone deficiency: molecular genetics and clinical spectrum". J Clin Endocrinol Metab. 93 (9): 3551–9. doi:10.1210/jc.2007-2654. PMC 2567850. PMID 18559922.