Adiponectin

ADIPOQ
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 4DOU
Identifiers
Aliases	ADIPOQ, ACDC, ACRP30, ADIPQTL1, ADPN, APM-1, APM1, GBP28, adiponectin, C1Q and collagen domain containing, Adiponectin
External IDs	OMIM: 605441 MGI: 106675 HomoloGene: 3525 GeneCards: ADIPOQ
Gene ontology Molecular function • hormone activity • receptor binding • cytokine activity • sialic acid binding • protein homodimerization activity • protein binding • identical protein binding Cellular component • extracellular region • extracellular space • cell surface • endoplasmic reticulum • extracellular exosome • protein complex • collagen trimer Biological process • positive regulation of glucose import • positive regulation of protein phosphorylation • negative regulation of receptor binding • low-density lipoprotein particle clearance • negative regulation of blood pressure • negative regulation of macrophage differentiation • negative regulation of synaptic transmission • generation of precursor metabolites and energy • cellular response to epinephrine stimulus • negative regulation of gluconeogenesis • cellular response to drug • regulation of glucose metabolic process • circadian rhythm • fatty acid oxidation • positive regulation of interleukin-8 production • glucose metabolic process • protein heterotrimerization • negative regulation of heterotypic cell-cell adhesion • response to ethanol • negative regulation of inflammatory response • cellular response to cAMP • positive regulation of protein kinase A signaling • negative regulation of platelet-derived growth factor receptor signaling pathway • positive regulation of signal transduction • positive regulation of cellular protein metabolic process • negative regulation of fat cell differentiation • response to linoleic acid • detection of oxidative stress • glucose homeostasis • adiponectin-activated signaling pathway • response to tumor necrosis factor • positive regulation of blood pressure • response to nutrient levels • positive regulation of cholesterol efflux • negative regulation of MAP kinase activity • cellular response to insulin stimulus • positive regulation of peptidyl-tyrosine phosphorylation • fatty acid beta-oxidation • negative regulation of tumor necrosis factor production • protein localization to plasma membrane • negative regulation of hormone secretion • protein homooligomerization • response to sucrose • positive regulation of metanephric glomerular visceral epithelial cell development • positive regulation of renal albumin absorption • negative regulation of granulocyte differentiation • response to nutrient • negative regulation of protein autophosphorylation • negative regulation of intracellular protein transport • membrane depolarization • response to glucose • positive regulation of myeloid cell apoptotic process • negative regulation of I-kappaB kinase/NF-kappaB signaling • negative regulation of metanephric mesenchymal cell migration • negative regulation of cell migration • positive regulation of fatty acid metabolic process • brown fat cell differentiation • positive regulation of cAMP-dependent protein kinase activity • positive regulation of glycogen (starch) synthase activity • negative regulation of transcription, DNA-templated • negative regulation of DNA biosynthetic process • positive regulation of protein kinase activity • negative regulation of smooth muscle cell proliferation • response to hypoxia • negative regulation of phagocytosis • membrane hyperpolarization • negative regulation of tumor necrosis factor-mediated signaling pathway • negative regulation of low-density lipoprotein particle receptor biosynthetic process • positive regulation of monocyte chemotactic protein-1 production • negative regulation of smooth muscle cell migration • response to glucocorticoid • response to activity • negative regulation of platelet-derived growth factor receptor-alpha signaling pathway • positive regulation of I-kappaB kinase/NF-kappaB signaling • negative regulation of ERK1 and ERK2 cascade • negative regulation of macrophage derived foam cell differentiation • response to drug Sources:Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	9370	11450
Ensembl	ENSG00000181092	ENSMUSG00000022878
UniProt	Q15848	Q60994
RefSeq (mRNA)	NM_001177800 NM_004797	NM_009605
RefSeq (protein)	NP_001171271.1 NP_004788.1	NP_033735.3
Location (UCSC)	Chr 3: 186.84 – 186.86 Mb	Chr 16: 23.15 – 23.16 Mb
PubMed search	[1]	[2]
Wikidata

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Adiponectin (also referred to as GBP-28, apM1, AdipoQ and Acrp30) is a protein which in humans is encoded by the ADIPOQ gene.^[3] It is involved in regulating glucose levels as well as fatty acid breakdown.

Structure

Adiponectin is a 244-amino-acid-long polypeptide (protein). There are four distinct regions of adiponectin. The first is a short signal sequence that targets the hormone for secretion outside the cell; next is a short region that varies between species; the third is a 65-amino acid region with similarity to collagenous proteins; the last is a globular domain. Overall this protein shows similarity to the complement 1Q factors (C1Q). However, when the 3-dimensional structure of the globular region was determined, a striking similarity to TNFα was observed, despite unrelated protein sequences.^[4]

Function

Adiponectin is a protein hormone that modulates a number of metabolic processes, including glucose regulation and fatty acid oxidation.^[5] Adiponectin is exclusively secreted from adipose tissue (and also from the placenta in pregnancy^[6]) into the bloodstream and is very abundant in plasma relative to many hormones. Many studies have found adiponectin to be inversely correlated with body mass index in patient populations.^[7] However, a meta analysis was not able to confirm this association in healthy adults.^[8] Circulating adiponectin concentrations increase during caloric restriction in animals and humans, such as in patients with anorexia nervosa. This observation is surprising, given that adiponectin is produced by adipose tissue. However, a recent study suggests that adipose tissue within bone marrow, which increases during caloric restriction, contributes to elevated circulating adiponectin in this context.^[9]

Transgenic mice with increased adiponectin show impaired adipocyte differentiation and increased energy expenditure associated with protein uncoupling.^[10] The hormone plays a role in the suppression of the metabolic derangements that may result in type 2 diabetes,^[7] obesity, atherosclerosis,^[5] non-alcoholic fatty liver disease (NAFLD) and an independent risk factor for metabolic syndrome.^[11] Adiponectin in combination with leptin has been shown to completely reverse insulin resistance in mice.^[12]

Adiponectin is secreted into the bloodstream where it accounts for approximately 0.01% of all plasma protein at around 5-10 μg/mL (mg/L). In adults, plasma concentrations are higher in females than males, and are reduced in diabetics compared to non-diabetics. Weight reduction significantly increases circulating concentrations.^[13]

Adiponectin automatically self-associates into larger structures. Initially, three adiponectin molecules bind together to form a homotrimer. The trimers continue to self-associate and form hexamers or dodecamers. Like the plasma concentration, the relative levels of the higher-order structures are sexually dimorphic, where females have increased proportions of the high-molecular weight forms. Recent studies showed that the high-molecular weight form may be the most biologically active form regarding glucose homeostasis.^[14] High-molecular-weight adiponectin was further found to be associated with a lower risk of diabetes with similar magnitude of association as total adiponectin.^[15] However, coronary artery disease has been found to be positively associated with high molecular weight adiponectin, but not with low molecular weight adiponectin.^[16]

Adiponectin exerts some of its weight reduction effects via the brain. This is similar to the action of leptin,^[17] but the two hormones perform complementary actions, and can have synergistic effects.

Receptors

Adiponectin binds to a number of receptors. So far, two receptors have been identified with homology to G protein-coupled receptors, and one receptor similar to the cadherin family:^[18][19]

• Adiponectin receptor 1 (AdipoR1)
• Adiponectin receptor 2 (AdipoR2)
• T-cadherin - CDH13

These have distinct tissue specificities within the body and have different affinities to the various forms of adiponectin. The receptors affect the downstream target AMP kinase, an important cellular metabolic rate control point. Expression of the receptors is correlated with insulin levels, as well as reduced in mouse models of diabetes, particularly in skeletal muscle and adipose tissue.^[20][21]

Discovery

Adiponectin was first characterised in 1995 in differentiating 3T3-L1 adipocytes (Scherer PE et al.).^[22] In 1996 it was characterised in mice as the mRNA transcript most highly expressed in adipocytes (Maeda, 1996 (citation #1, below)). In 2007, adiponectin was identified as a transcript highly expressed in preadipocytes^[23] (precursors of fat cells) differentiating into adipocytes.^[23][24]

The human homologue was identified as the most abundant transcript in adipose tissue. Contrary to expectations, despite being produced in adipose tissue, adiponectin was found to be decreased in obesity.^[5][7][17] This downregulation has not been fully explained. The gene was localised to chromosome 3q27, a region highlighted as affecting genetic susceptibility to type 2 diabetes and obesity. Supplementation by differing forms of adiponectin was able to improve insulin control, blood glucose and triglyceride levels in mouse models.

The gene was investigated for variants that predispose to type 2 diabetes.^{[17][23][25][26][27][28]} Several single nucleotide polymorphisms in the coding region and surrounding sequence were identified from several different populations, with varying prevalences, degrees of association and strength of effect on type 2 diabetes. Berberine, an herbal folk medicine, has been shown to increase adiponectin expression^[29] which partly explains its beneficial effects on metabolic disturbances. Mice fed the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have shown increased plasma adiponectin.^[30] Curcumin, capsaicin, gingerol, and catechins have also been found to increase adiponectin expression.^[31]

Phylogenetic distribution includes expression in birds^[32] and fish.^[33]

Metabolic

Adiponectin effects:

• glucose flux
  • decreased gluconeogenesis
  • increased glucose uptake^[5][17][26]
• lipid catabolism^[26]
  • β-oxidation^[17]
  • triglyceride clearance^[17]
• protection from endothelial dysfunction (important facet of atherosclerotic formation)
• insulin sensitivity
• weight loss
• control of energy metabolism.^[26]
• upregulation of uncoupling proteins ^[10]
• reduction of TNF-alpha

Regulation of adiponectin

• Obesity is associated with decreased adiponectin.
  • The exact mechanism of regulation is unknown, but adiponectin could be regulated by post-translational mechanisms in cells.^[34]

Hypoadiponectinemia

A low level of adiponectin is an independent risk factor for developing:

• Metabolic syndrome^[11]
• Diabetes mellitus^{[17][23][25][27][28]}

Other

Lower levels of adiponectin are associated with ADHD in adults.^[35]

Adiponectin levels were found to be increased in rheumatoid arthritis patients responding to DMARDs or TNF inhibitor therapy.^[36]

Exercise induced release of adiponectin increased hippocampal growth and led to antidepressive symptoms in mice.^[37]

As a drug target

Circulating levels of adiponectin can indirectly be increased through lifestyle modifications and certain drugs such as statins.^[38]

A small molecule adiponectin receptor AdipoR1 and AdipoR2 agonist, AdipoRon, has been reported.^[39]

Extracts of sweet potatoes have been reported to increase levels of adiponectin and thereby improve glycemic control in humans.^[40] However, a systematic review concluded there is insufficient evidence to support the consumption of sweet potatoes to treat type 2 diabetes mellitus.^[41]

Adiponectin is apparently able to cross the blood-brain-barrier.^[42] However, conflicting data on this issue exist.^[43] Adiponectin has a half-life of 2.5 hours in humans.^[44]

References

1. "Human PubMed Reference:".
2. "Mouse PubMed Reference:".
3. Maeda K, Okubo K, Shimomura I, Funahashi T, Matsuzawa Y, Matsubara K (1996). "cDNA cloning and expression of a novel adipose specific collagen-like factor, apM1 (AdiPose Most abundant Gene transcript 1)". Biochem. Biophys. Res. Commun. 221 (2): 286–9. doi:10.1006/bbrc.1996.0587. PMID 8619847.
4. Shapiro L, Scherer PE (1998). "The crystal structure of a complement-1q family protein suggests an evolutionary link to tumor necrosis factor". Curr. Biol. 8 (6): 335–8. doi:10.1016/S0960-9822(98)70133-2. PMID 9512423.
5. Díez JJ, Iglesias P (2003). "The role of the novel adipocyte-derived hormone adiponectin in human disease". Eur. J. Endocrinol. 148 (3): 293–300. doi:10.1530/eje.0.1480293. PMID 12611609.
6. Chen J, Tan B, Karteris E, Zervou S, Digby J, Hillhouse EW, Vatish M, Randeva HS (2006). "Secretion of adiponectin by human placenta: differential modulation of adiponectin and its receptors by cytokines". Diabetologia. 49 (6): 1292–302. doi:10.1007/s00125-006-0194-7. PMID 16570162.
7. Ukkola O, Santaniemi M (2002). "Adiponectin: a link between excess adiposity and associated comorbidities?". J. Mol. Med. 80 (11): 696–702. doi:10.1007/s00109-002-0378-7. PMID 12436346.
8. Kuo SM, Halpern MM (2011). "Lack of association between body mass index and plasma adiponectin levels in healthy adults". Int J Obes (Lond). 35 (12): 1487–94. doi:10.1038/ijo.2011.20. PMID 21364526.
9. Cawthorn WP, Scheller EL, Learman BS, Parlee SD, Simon BR, Mori H, Ning X, Bree AJ, Schell B, Broome DT, Soliman SS, DelProposto JL, Lumeng CN, Mitra A, Pandit SV, Gallagher KA, Miller JD, Krishnan V, Hui SK, Bredella MA, Fazeli PK, Klibanski A, Horowitz MC, Rosen CJ, MacDougald OA (2014). "Bone marrow adipose tissue is an endocrine organ that contributes to increased circulating adiponectin during caloric restriction". Cell Metab. 20 (2): 368–375. doi:10.1016/j.cmet.2014.06.003. PMID 24998914.
10. Bauche IB, El Mkadem SA, Pottier AM, Senou M, Many MC, Rezsohazy R, Penicaud L, Maeda N, Funahashi T, Brichard SM (2007). "Overexpression of adiponectin targeted to adipose tissue in transgenic mice: impaired adipocyte differentiation". Endocrinology. 148 (4): 1539–49. doi:10.1210/en.2006-0838. PMID 17204560.
11. Renaldi O, Pramono B, Sinorita H, Purnomo LB, Asdie RH, Asdie AH (2009). "Hypoadiponectinemia: a risk factor for metabolic syndrome". Acta Med Indones. 41 (1): 20–4. PMID 19258676.
12. Yamauchi T, Kamon J, Waki H, Terauchi Y, Kubota N, Hara K, Mori Y, Ide T, Murakami K, Tsuboyama-Kasaoka N, Ezaki O, Akanuma Y, Gavrilova O, Vinson C, Reitman ML, Kagechika H, Shudo K, Yoda M, Nakano Y, Tobe K, Nagai R, Kimura S, Tomita M, Froguel P, Kadowaki T (2001). "The fat-derived hormone adiponectin reverses insulin resistance associated with both lipoatrophy and obesity". Nat. Med. 7 (8): 941–6. doi:10.1038/90984. PMID 11479627.
13. Coppola A, Marfella R, Coppola L, Tagliamonte E, Fontana D, Liguori E, Cirillo T, Cafiero M, Natale S, Astarita C (2009). "Effect of weight loss on coronary circulation and adiponectin levels in obese women". Int. J. Cardiol. 134 (3): 414–6. doi:10.1016/j.ijcard.2007.12.087. PMID 18378021.
14. Oh DK, Ciaraldi T, Henry RR Adiponectin in health and disease. Diabetes Obes Metab 2007:9:282–289
15. Zhu N, Pankow JS, Ballantyne CM, Couper D, Hoogeveen RC, Pereira M, Duncan BB, Schmidt MI (2010). "High-molecular-weight adiponectin and the risk of type 2 diabetes in the ARIC study". J. Clin. Endocrinol. Metab. 95 (11): 5097–104. doi:10.1210/jc.2010-0716. PMC 2968724. PMID 20719834.
16. Rizza S, Gigli F, Galli A, Micchelini B, Lauro D, Lauro R, Federici M (2010). "Adiponectin isoforms in elderly patients with or without coronary artery disease". J Am Geriatr Soc. 58 (4): 702–706. doi:10.1111/j.1532-5415.2010.02773.x. PMID 20398150.
17. Nedvídková J, Smitka K, Kopský V, Hainer V (2005). "Adiponectin, an adipocyte-derived protein" (PDF). Physiol Res. 54 (2): 133–40. PMID 15544426.
18. Yamauchi T, Kamon J, Ito Y, Tsuchida A, Yokomizo T, Kita S, Sugiyama T, Miyagishi M, Hara K, Tsunoda M, Murakami K, Ohteki T, Uchida S, Takekawa S, Waki H, Tsuno NH, Shibata Y, Terauchi Y, Froguel P, Tobe K, Koyasu S, Taira K, Kitamura T, Shimizu T, Nagai R, Kadowaki T (2003). "Cloning of adiponectin receptors that mediate antidiabetic metabolic effects". Nature. 423 (6941): 762–9. doi:10.1038/nature01705. PMID 12802337.
19. Hug C, Wang J, Ahmad NS, Bogan JS, Tsao TS, Lodish HF (2004). "T-cadherin is a receptor for hexameric and high-molecular-weight forms of Acrp30/adiponectin". Proc. Natl. Acad. Sci. U.S.A. 101 (28): 10308–13. doi:10.1073/pnas.0403382101. PMC 478568. PMID 15210937.
20. Fang X, Sweeney G (2006). "Mechanisms regulating energy metabolism by adiponectin in obesity and diabetes". Biochem. Soc. Trans. 34 (Pt 5): 798–801. doi:10.1042/BST0340798. PMID 17052201.
21. Bonnard C, Durand A, Vidal H, Rieusset J (2008). "Changes in adiponectin, its receptors and AMPK activity in tissues of diet-induced diabetic mice". Diabetes Metab. 34 (1): 52–61. doi:10.1016/j.diabet.2007.09.006. PMID 18222103.
22. Scherer PE, Williams S, Fogliano M, Baldini G, Lodish HF (Nov 1995). "A novel serum protein similar to C1q, produced exclusively in adipocytes". J Biol Chem. 270 (45): 26746–9. doi:10.1074/jbc.270.45.26746. PMID 7592907.
23. Lara-Castro C, Fu Y, Chung BH, Garvey WT (2007). "Adiponectin and the metabolic syndrome: mechanisms mediating risk for metabolic and cardiovascular disease". Curr. Opin. Lipidol. 18 (3): 263–70. doi:10.1097/MOL.0b013e32814a645f. PMID 17495599.
24. Matsuzawa Y, Funahashi T, Kihara S, Shimomura I (2004). "Adiponectin and metabolic syndrome". Arterioscler. Thromb. Vasc. Biol. 24 (1): 29–33. doi:10.1161/01.ATV.0000099786.99623.EF. PMID 14551151.
25. Hara K, Yamauchi T, Kadowaki T (2005). "Adiponectin: an adipokine linking adipocytes and type 2 diabetes in humans". Curr. Diab. Rep. 5 (2): 136–40. doi:10.1007/s11892-005-0041-0. PMID 15794918.
26. Vasseur F, Leprêtre F, Lacquemant C, Froguel P (2003). "The genetics of adiponectin". Curr. Diab. Rep. 3 (2): 151–8. doi:10.1007/s11892-003-0039-4. PMID 12728641.
27. Hug C, Lodish HF (2005). "The role of the adipocyte hormone adiponectin in cardiovascular disease". Curr Opin Pharmacol. 5 (2): 129–34. doi:10.1016/j.coph.2005.01.001. PMID 15780820.
28. Vasseur F, Meyre D, Froguel P (2006). "Adiponectin, type 2 diabetes and the metabolic syndrome: lessons from human genetic studies". Expert Rev Mol Med. 8 (27): 1–12. doi:10.1017/S1462399406000147. PMID 17112391.
29. Choi BH, Kim YH, Ahn IS, Ha JH, Byun JM, Do MS (2009). "The inhibition of inflammatory molecule expression on 3T3-L1 adipocytes by berberine is not mediated by leptin signaling". Nutr Res Pract. 3 (2): 84–8. doi:10.4162/nrp.2009.3.2.84. PMC 2788178. PMID 20016706.
30. Grimshaw CE, Matthews DA, Varughese KI, Skinner M, Xuong NH, Bray T, Hoch J, Whiteley JM (1992). "Characterization and nucleotide binding properties of a mutant dihydropteridine reductase containing an aspartate 37-isoleucine replacement". J. Biol. Chem. 267 (22): 15334–9. PMID 1639779.
31. Nigro E, Scudiero O, Monaco ML, Palmieri A, Mazzarella G, Costagliola C, Bianco A, Daniele A (2014). "New insight into adiponectin role in obesity and obesity-related diseases". Biomed Res Int. 2014: 658913. doi:10.1155/2014/658913. PMC 4109424. PMID 25110685.
32. Yuan J, Liu W, Liu ZL, Li N (2006). "cDNA cloning, genomic structure, chromosomal mapping and expression analysis of ADIPOQ (adiponectin) in chicken". Cytogenet. Genome Res. 112 (1-2): 148–51. doi:10.1159/000087527. PMID 16276104.
33. Nishio S, Gibert Y, Bernard L, Brunet F, Triqueneaux G, Laudet V (2008). "Adiponectin and adiponectin receptor genes are coexpressed during zebrafish embryogenesis and regulated by food deprivation". Dev. Dyn. 237 (6): 1682–90. doi:10.1002/dvdy.21559. PMID 18489000.
34. Liu M, Liu F (2012). "Up- and down-regulation of adiponectin expression and multimerization: mechanisms and therapeutic implication". Biochimie. 94 (10): 2126–30. doi:10.1016/j.biochi.2012.01.008. PMC 3542391. PMID 22342903.
35. Mavroconstanti T, Halmøy A, Haavik J (2014). "Decreased serum levels of adiponectin in adult attention deficit hyperactivity disorder". Psychiatry Res. 216 (1): 123–30. doi:10.1016/j.psychres.2014.01.025. PMID 24559850.
36. Kim KS, Choi HM, Ji HI, Song R, Yang HI, Lee SK, Yoo MC, Park YB (2014). "Serum adipokine levels in rheumatoid arthritis patients and their contributions to the resistance to treatment". Mol Med Rep. 9 (1): 255–60. doi:10.3892/mmr.2013.1764. PMID 24173909.
37. Yau SY, Li A, Hoo RL, Ching YP, Christie BR, Lee TM, Xu A, So KF (2014). "Physical exercise-induced hippocampal neurogenesis and antidepressant effects are mediated by the adipocyte hormone adiponectin". Proc. Natl. Acad. Sci. U.S.A. 111 (44): 15810–15815. doi:10.1073/pnas.1415219111. PMC 4226125. PMID 25331877.
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39. Okada-Iwabu M, Yamauchi T, Iwabu M, Honma T, Hamagami K, Matsuda K, Yamaguchi M, Tanabe H, Kimura-Someya T, Shirouzu M, Ogata H, Tokuyama K, Ueki K, Nagano T, Tanaka A, Yokoyama S, Kadowaki T (Nov 2013). "A small-molecule AdipoR agonist for type 2 diabetes and short life in obesity". Nature. 503 (7477): 493–9. doi:10.1038/nature12656. PMID 24172895.
40. Ludvik B, Hanefeld M, Pacini G (2008). "Improved metabolic control by Ipomoea batatas (Caiapo) is associated with increased adiponectin and decreased fibrinogen levels in type 2 diabetic subjects". Diabetes Obes Metab. 10 (7): 586–92. doi:10.1111/j.1463-1326.2007.00752.x. PMID 17645559.
41. Ooi CP, Loke SC (2013). "Sweet potato for type 2 diabetes mellitus". Cochrane Database Syst Rev. 9: CD009128. doi:10.1002/14651858.CD009128.pub3. PMID 24000051.
42. Yau SY, Li A, Hoo RL, Ching YP, Christie BR, Lee TM, Xu A, So KF (2014). "Physical exercise-induced hippocampal neurogenesis and antidepressant effects are mediated by the adipocyte hormone adiponectin". Proc. Natl. Acad. Sci. U.S.A. 111 (44): 15810–5. doi:10.1073/pnas.1415219111. PMC 4226125. PMID 25331877.
43. Spranger J, Verma S, Göhring I, Bobbert T, Seifert J, Sindler AL, Pfeiffer A, Hileman SM, Tschöp M, Banks WA (2006). "Adiponectin does not cross the blood-brain barrier but modifies cytokine expression of brain endothelial cells". Diabetes. 55 (1): 141–7. doi:10.2337/diabetes.55.1.141. PMID 16380487.
44. Hoffstedt J, Arvidsson E, Sjölin E, Wåhlén K, Arner P (2004). "Adipose tissue adiponectin production and adiponectin serum concentration in human obesity and insulin resistance". J. Clin. Endocrinol. Metab. 89 (3): 1391–6. doi:10.1210/jc.2003-031458. PMID 15001639.