pro-opiomelanocortin |
Identifiers |
Symbol |
POMC |
Entrez |
5443 |
HUGO |
9201 |
OMIM |
176830 |
RefSeq |
NM_000939 |
UniProt |
P01189 |
Other data |
Locus |
Chr. 2 p23 |
Melanocyte-stimulating hormone
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Clinical data |
Legal status |
? |
Identifiers |
ATC code |
? |
ChEMBL |
CHEMBL214332 N |
Chemical data |
Formula |
? |
N (what is this?) (verify) |
The melanocyte-stimulating hormones (collectively referred to as MSH or intermedins) are a class of peptide hormones that are produced by cells in the intermediate lobe of the pituitary gland. Synthetic analogs of these naturally occurring hormones have also been developed and researched.
Contents
- 1 Function
- 1.1 In amphibians
- 1.2 In humans
- 2 Structure of MSH
- 3 Synthetic MSH
- 4 See also
- 5 References
- 6 Further reading
- 7 External links
Function[edit]
They stimulate the production and release of melanin (melanogenesis) by melanocytes in skin and hair. MSH signals to the brain have effects on appetite and sexual arousal.
In amphibians[edit]
In some animals (such as the claw-toed frog Xenopus laevis) production of MSH is increased when the animal is in a dark location. This causes pigment to be dispersed in pigment cells in the toad's skin, making it become darker, and harder for predators to spot. The pigment cells are called melanophores and therefore, in amphibians, the hormone is often called melanophore-stimulating hormone.
In humans[edit]
An increase in MSH will cause a darkening in humans too. Melanocyte-stimulating hormone increases in humans during pregnancy. This, along with increased estrogens, causes increased pigmentation in pregnant women. Cushing's syndrome due to excess adrenocorticotropic hormone (ACTH) may also result in hyperpigmentation, such as acanthosis nigricans in the axilla. Most people with primary Addison's have darkening (hyperpigmentation) of the skin, including areas not exposed to the sun; characteristic sites are skin creases (e.g. of the hands), nipple, and the inside of the cheek (buccal mucosa), new scars become hyperpigmented, whereas older ones do not darken. This occurs because melanocyte-stimulating hormone (MSH) and adrenocorticotropic hormone (ACTH) share the same precursor molecule, Pro-opiomelanocortin (POMC).
Different levels of MSH are not the major cause of racial variation in skin colour. However, in many red headed people, and other people who do not tan well, there are variations in their hormone receptors, causing them to not respond to MSH in the blood.
See melanocortin receptor for more information.
Structure of MSH[edit]
proopiomelanocortin derivatives |
POMC |
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γ-MSH |
ACTH |
β-lipotropin |
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α-MSH |
CLIP |
γ-lipotropin |
β-endorphin |
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β-MSH |
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Melanocyte-stimulating hormone belongs to a group called the melanocortins. This group includes ACTH, alpha-melanocyte-stimulating hormone (α-MSH), beta-melanocyte-stimulating hormone (β-MSH) and gamma-melanocyte-stimulating hormone (γ-MSH); these peptides are all cleavage products of a large precursor peptide called pro-opiomelanocortin (POMC). α-MSH is the most important melanocortin for pigmentation.
The different melanocyte-stimulating hormones have the following amino acid sequences:
α-MSH: |
Ac-Ser-Tyr-Ser-Met-Glu-His-Phe-Arg-Trp-Gly-Lys-Pro-Val |
β-MSH (human): |
Ala-Glu-Lys-Lys-Asp-Glu-Gly-Pro-Tyr-Arg-Met-Glu-His-Phe-Arg-Trp-Gly-Ser-Pro-Pro-Lys-Asp |
β-MSH (porcine): |
Asp-Glu-Gly-Pro-Tyr-Lys-Met-Glu-His-Phe-Arg-Trp-Gly-Ser-Pro-Pro-Lys-Asp |
γ-MSH: |
Tyr-Val-Met-Gly-His-Phe-Arg-Trp-Asp-Arg-Phe-Gly |
Synthetic MSH[edit]
Synthetic analogs of α-MSH have been developed for human use. Two of the better known are afamelanotide (melanotan-1) in testing by Clinuvel Pharmaceuticals in Australia and bremelanotide by Palatin Technologies, a New Jersey company.
- Afamelanotide (formerly CUV1647) is being investigated as a method of photoprotection in patients with erythropoietic protoporphyria, polymorphous light eruption, actinic keratosis and squamous cell carcinoma (a form of skin cancer).[1]
- An additional analog called Melanotan II causes enhanced libido and erections in most male test subject and arousal with corresponding genital involvement in most female test subjects.[2] Bremelanotide (formerly PT-141) which stemmed from Melanotan II research is currently under development by a New Jersey company for its aphrodisiac effects. These effects are mediated by actions in the hypothalamus on neurons that express MC3R and MC4R receptors.
See also[edit]
- Melanocyte-inhibiting factor
- Excess MSH leads to Nelson's syndrome
References[edit]
- ^ Clinuvel FAQs
- ^ Hadley ME (Oct 2005). "Discovery that a melanocortin regulates sexual functions in male and female humans". Peptides 26 (10): 1687–9. doi:10.1016/j.peptides.2005.01.023. PMID 15996790.
Further reading[edit]
- Millington GW (May 2006). "Proopiomelanocortin (POMC): the cutaneous roles of its melanocortin products and receptors". Clin. Exp. Dermatol. 31 (3): 407–12. doi:10.1111/j.1365-2230.2006.02128.x. PMID 16681590.
- Millington GW (2007). "The role of proopiomelanocortin (POMC) neurones in feeding behaviour". Nutr Metab (Lond) 4: 18. doi:10.1186/1743-7075-4-18. PMC 2018708. PMID 17764572.
External links[edit]
- Melanocyte-Stimulating Hormones at the US National Library of Medicine Medical Subject Headings (MeSH)
- Clinuvel Pharmaceuticals
- Palatin Technologies
- Endocrine system:
- hormones
- Peptide hormones
- Steroid hormones
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Endocrine
glands |
Hypothalamic-
pituitary
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Hypothalamus
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- GnRH
- TRH
- Dopamine
- CRH
- GHRH/Somatostatin
- Melanin concentrating hormone
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Posterior pituitary
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Anterior pituitary
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- α
- FSH
- FSHB
- LH
- LHB
- TSH
- TSHB
- CGA
- Prolactin
- POMC
- CLIP
- ACTH
- MSH
- Endorphins
- Lipotropin
- GH
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Adrenal axis
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Adrenal cortex:
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- aldosterone
- cortisol
- DHEA
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Adrenal medulla:
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- epinephrine
- norepinephrine
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Thyroid axis
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Thyroid:
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- thyroid hormone
- calcitonin
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Parathyroid:
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Gonadal axis
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Testis::
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Ovary:
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- estradiol
- progesterone
- activin and inhibin
- relaxin (pregnancy)
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Placenta:
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- hCG
- HPL
- estrogen
- progesterone
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Islet-Acinar
Axis
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Pancreas:
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- glucagon
- insulin
- amylin
- somatostatin
- pancreatic polypeptide
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Pineal gland
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Other
glands |
Thymus:
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- Thymosins
- Thymosin α1
- Beta thymosins
- Thymopoietin
- Thymulin
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Digestive system:
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Stomach:
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Duodenum:
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- CCK
- Incretins
- secretin
- motilin
- VIP
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Ileum:
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- enteroglucagon
- peptide YY
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Liver/other
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- Insulin-like growth factor
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Adipose tissue:
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- leptin
- adiponectin
- resistin
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Skeleton::
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Kidney:
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- JGA (renin)
- peritubular cells
- calcitriol
- prostaglandin
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Heart:
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noco (d)/cong/tumr, sysi/epon
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proc, drug (A10/H1/H2/H3/H5)
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Peptides: neuropeptides
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Hormones |
see hormones
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Opioid peptides |
Dynorphin
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- Big dynorphin
- Dynorphin A
- Dynorphin B
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Endorphins
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- Beta-endorphin
- Alpha-endorphin
- Gamma-endorphin
- α-neo-endorphin
- β-neo-endorphin
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Enkephalin
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- Met-enkephalin
- Leu-enkephalin
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Others
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- Adrenorphin
- Amidorphin
- Leumorphin
- Nociceptin
- Opiorphin
- Spinorphin
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Other
neuropeptides |
Kinins
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- Tachykinins: mammal
- Substance P
- Neurokinin A
- Neurokinin B
- amphibian
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Neuromedins
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Other
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- Angiotensin
- Bombesin
- Calcitonin gene-related peptide
- Carnosine
- Cocaine and amphetamine regulated transcript
- Delta sleep-inducing peptide
- FMRFamide
- Galanin
- Galanin-like peptide
- Gastrin releasing peptide
- Neuropeptide S
- Neuropeptide Y
- Neurophysins
- Neurotensin
- Pancreatic polypeptide
- Pituitary adenylate cyclase activating peptide
- RVD-Hpα
- VGF
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B trdu: iter (nrpl/grfl/cytl/horl), csrc (lgic, enzr, gprc, igsr, intg, nrpr/grfr/cytr), itra (adap, gbpr, mapk), calc, lipd; path (hedp, wntp, tgfp+mapp, notp, jakp, fsap, hipp, tlrp)
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Neurotransmitters
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Amino acids |
- Alanine
- Aspartate
- Cycloserine
- DMG
- GABA
- Glutamate
- Glycine
- Hypotaurine
- Kynurenic acid (Transtorine)
- NAAG (Spaglumic acid)
- NMG (Sarcosine)
- Serine
- Taurine
- TMG (Betaine)
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Endocannabinoids |
- 2-AG
- 2-AGE (Noladin ether)
- AEA (Anandamide)
- NADA
- OAE (Virodhamine)
- Oleamide
- PEA (Palmitoylethanolamide)
- RVD-Hpα
- Hp (Hemopressin)
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Gasotransmitters |
- Carbon monoxide
- Hydrogen sulfide
- Nitric oxide
- Nitrous oxide
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Monoamines |
Dopamine
- Epinephrine (Adrenaline)
- Melatonin
- NAS (Normelatonin)
- Norepinephrine (Noradrenaline)
- Serotonin (5-HT)
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Purines |
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Trace amines |
- 3-ITA
- 5-MeO-DMT
- Bufotenin
- DMT
- m-Octopamine
- p-Octopamine
- m-Tyramine
- p-Tyramine
- NMT
- Phenethylamine
- Synephrine
- Thyronamine
- Tryptamine
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Others |
- 1,4-BD
- Acetylcholine
- GBL
- GHB
- Histamine
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See also Template:Neuropeptides
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anat (h/r/t/c/b/l/s/a)/phys (r)/devp/prot/nttr/nttm/ntrp
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noco/auto/cong/tumr, sysi/epon, injr
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Neuropeptidergics
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Cholecystokinin |
CCKA
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- Agonists: Cholecystokinin
- CCK-4
Antagonists: Asperlicin
- Proglumide
- Lorglumide
- Devazepide
- Dexloxiglumide
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CCKB
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- Agonists: Cholecystokinin
- CCK-4
- Gastrin
Antagonists: Proglumide
- CI-988
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CRH |
CRF1
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- Agonists: Corticotropin releasing hormone
Antagonists: Antalarmin
- CP-154,526
- Pexacerfont
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CRF2
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- Agonists: Corticotropin releasing hormone
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Galanin |
GAL1
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- Agonists: Galanin
- Galanin-like peptide
- Galmic
- Galnon
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GAL2
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- Agonists: Galanin
- Galanin-like peptide
- Galmic
- Galnon
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GAL3
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- Agonists: Galanin
- Galmic
- Galnon
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Ghrelin |
- Agonists: Ghrelin
- Capromorelin
- MK-677
- Sermorelin
- SM-130,686
- Tabimorelin
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GnRH |
- Agonists: Buserelin
- Deslorelin
- GnRH
- Goserelin
- Histrelin
- Leuprorelin
- Nafarelin
- Triptorelin
Antagonists: Abarelix
- Cetrorelix
- Degarelix
- Ganirelix
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MCH |
MCH1
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- Agonists: Melanin concentrating hormone
Antagonists: ATC-0175
- GW-803,430
- NGD-4715
- SNAP-7941
- SNAP-94847
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MCH2
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- Agonists: Melanin concentrating hormone
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Melanocortin |
MC1
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- Agonists: alpha-MSH
- Afamelanotide
- BMS-470,539
- Bremelanotide
- Melanotan II
Antagonists: Agouti signalling peptide
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MC2
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- Agonists: ACTH
- Cosyntropin
- Tetracosactide
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MC3
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- Agonists: alpha-MSH
- Bremelanotide
- Melanotan II
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MC4
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- Agonists: alpha-MSH
- Bremelanotide
- Melanotan II
- PF-00446687
- THIQ
Antagonists: Agouti-related peptide
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MC5
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- Agonists: alpha-MSH
- Melanotan II
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Neuropeptide S |
- Agonists: Neuropeptide S
Antagonists: SHA-68
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Neuropeptide Y |
Y1
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- Agonists: Neuropeptide Y
- Peptide YY
Antagonists: BIBP-3226
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Y2
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- Agonists: Neuropeptide Y
- Peptide YY
Antagonists: BIIE-0246
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Y4
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- Agonists: Neuropeptide Y
- Pancreatic polypeptide
- Peptide YY
Antagonists: UR-AK49
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Y5
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- Agonists: Neuropeptide Y
- Peptide YY
Antagonists: Lu AA-33810
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Neurotensin |
NTS1
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- Agonists: Neurotensin
- Neuromedin N
Antagonists: SR-48692
- SR-142,948
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NTS2
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- Agonists: Neurotensin
Antagonists: Levocabastine
- SR-142,948
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Orexin |
OX1
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- Agonists: Orexin-A
Antagonists: Almorexant
- SB-334,867
- SB-408,124
- SB-649,868
- Suvorexant
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OX2
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- Agonists: Orexin-A
Antagonists: Almorexant
- SB-649,868
- Suvorexant
- TCS-OX2-29
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Oxytocin |
- Agonists: Carbetocin
- Demoxytocin
- Oxytocin
- WAY-267,464
Antagonists: Atosiban
- Epelsiban
- L-371,257
- L-368,899
- Retosiban
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Tachykinin |
NK1
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- Agonists: Substance P
Antagonists: Aprepitant
- Befetupitant
- Casopitant
- CI-1021
- CP-96,345
- CP-99,994
- CP-122,721
- Dapitant
- Ezlopitant
- FK-888
- Fosaprepitant
- GR-203,040
- GW-597,599
- HSP-117
- L-733,060
- L-741,671
- L-743,310
- L-758,298
- Lanepitant
- LY-306,740
- Maropitant
- Netupitant
- NKP-608
- Nolpitantium
- Orvepitant
- RP-67,580
- SDZ NKT 343
- Vestipitant
- Vofopitant
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NK2
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- Agonists: Neurokinin A
Antagonists: GR-159,897
- Ibodutant
- Saredutant
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NK3
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- Agonists: Neurokinin B
Antagonists: Osanetant
- Talnetant
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Vasopressin |
V1A
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- Agonists: Desmopressin
- Felypressin
- Ornipressin
- Terlipressin
- Vasopressin
Antagonists: Conivaptan
- Demeclocycline
- Relcovaptan
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V1B
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- Agonists: Felypressin
- Ornipressin
- Terlipressin
- Vasopressin
Antagonists: Demeclocycline
- Nelivaptan
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V2
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- Agonists: Desmopressin
- Ornipressin
- Vasopressin
Antagonists: Conivaptan
- Demeclocycline
- Lixivaptan
- Mozavaptan
- Satavaptan
- Tolvaptan
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