Major depressive disorder is a complex neuropsychiatric disorder with few treatment options. Non-targeted antidepressants have low efficacy and can induce series of side effects. While a neuropeptide, melanin-concentrating hormone (MCH), is known to exhibit regulator of affective state, no study to date has assessed the anti-depressive effects of MCH in a stress-induced depression model. This study aimed to evaluate the pharmacological effects of intranasal administration of MCH on depression-related behavior in stressed rats and mice. Using a number of behavioral tests, we found that MCH treatment significantly decreased anxiety- and depressive-like behaviors induced by stress. Notably, the effects of MCH were equivalent to those of fluoxetine. MCH treatment also restored the activity of the mammalian target of rapamycin (mTOR) signaling pathway and normalized the levels of synaptic proteins, including postsynaptic density 95, glutamate receptor 1, and synapsin 1, which were all downregulated by stress. Interestingly, the protective effects of MCH were blocked by the mTOR inhibitor, rapamycin. These results suggest that MCH exhibits antidepressant properties by modulating the mTOR pathway. Altogether, this study provides an insight into the molecular mechanisms involved in the antidepressant-like effects of MCH, thereby paving the way for the future clinical application of MCH.
1. American Psychiatric Association (2013) Diagnostic and statistical manual of mental disorders: DSM-5. 5th ed. AmericanPsychiatric Association, Arlington.
2. World Health Organization (2008) The global burden of disease: 2004 update. World Health Organization, Geneva.
3. Young EA, Kotun J, Haskett RF, Grunhaus L, Greden JF, Watson SJ, Akil H (1993) Dissociation between pituitary and adrenal suppression to dexamethasone in depression. Arch GenPsychiatry 50:395-403.
6. Monti JM (2010) The role of dorsal raphe nucleus serotonergic and non-serotonergic neurons, and of their receptors,in regulating waking and rapid eye movement (REM) sleep.Sleep Med Rev 14:319-327.
9. Kawauchi H, Kawazoe I, Tsubokawa M, Kishida M, Baker BI(1983) Characterization of melanin-concentrating hormonein chum salmon pituitaries. Nature 305:321-323.
12. Qu D, Ludwig DS, Gammeltoft S, Piper M, PelleymounterMA, Cullen MJ, Mathes WF, Przypek R, Kanarek R, MaratosFlier E (1996) A role for melanin-concentrating hormone inthe central regulation of feeding behaviour. Nature 380:243-247.
13. Bittencourt JC, Presse F, Arias C, Peto C, Vaughan J, NahonJL, Vale W, Sawchenko PE (1992) The melanin-concentratinghormone system of the rat brain: an immuno- and hybridization histochemical characterization. J Comp Neurol 319:218-245.
14. Saito Y, Cheng M, Leslie FM, Civelli O (2001) Expressionof the melanin-concentrating hormone (MCH) receptormRNA in the rat brain. J Comp Neurol 435:26-40.
15. Mashiko S, Ishihara A, Gomori A, Moriya R, Ito M, Iwaasa H,Matsuda M, Feng Y, Shen Z, Marsh DJ, Bednarek MA, MacNeil DJ, Kanatani A (2005) Antiobesity effect of a melaninconcentrating hormone 1 receptor antagonist in diet-inducedobese mice. Endocrinology 146:3080-3086.
16. Bencze J, Pocsai K, Murnyák B, Gergely PA, Juhász B, SzilvássyZ, Hortobágyi T (2018) The Melanin-concentrating hormonesystem in human, rodent and avian brain. Open Med (Wars)13:264-269.
19. Benedetto L, Rodriguez-Servetti Z, Lagos P, D'Almeida V,Monti JM, Torterolo P (2013) Microinjection of melanin concentrating hormone into the lateral preoptic area promotesnon-REM sleep in the rat. Peptides 39:11-15.
20. Adams AC, Domouzoglou EM, Chee MJ, Segal-LiebermanG, Pissios P, Maratos-Flier E (2011) Ablation of the hypothalamic neuropeptide melanin concentrating hormone is associated with behavioral abnormalities that reflect impairedolfactory integration. Behav Brain Res 224:195-200.
22. Belzung C (2014) Innovative drugs to treat depression: didanimal models fail to be predictive or did clinical trials fail todetect effects? Neuropsychopharmacology 39:1041-1051.
23. Jang JH, Park JY, Oh JY, Bae SJ, Jang H, Jeon S, Kim J, Park HJ(2018) Novel analgesic effects of melanin-concentrating hormone on persistent neuropathic and inflammatory pain inmice. Sci Rep 8:707.
24. Serova LI, Laukova M, Alaluf LG, Sabban EL (2013) Intranasal infusion of melanocortin receptor four (MC4R) antagonist to rats ameliorates development of depression andanxiety related symptoms induced by single prolonged stress.Behav Brain Res 250:139-147.
25. Koprdova R, Bögi E, Belovičová K, Sedláčková N, OkuliarováM, Ujházy E, Mach M (2016) Chronic unpredictable mildstress paradigm in male Wistar rats: effect on anxiety- anddepressive-like behavior. Neuro Endocrinol Lett 37(Suppl1):103-110.
26. Shin MS, Park SS, Lee JM, Kim TW, Kim YP (2017) Treadmillexercise improves depression-like symptoms by enhancingserotonergic function through upregulation of 5-HT1A expression in the olfactory bulbectomized rats. J Exerc Rehabil13:36-42.
27. Ignácio ZM, Réus GZ, Arent CO, Abelaira HM, Pitcher MR,Quevedo J (2016) New perspectives on the involvement ofmTOR in depression as well as in the action of antidepressantdrugs. Br J Clin Pharmacol 82:1280-1290.
32. Hawes BE, Kil E, Green B, O'Neill K, Fried S, Graziano MP(2000) The melanin-concentrating hormone receptor couplesto multiple G proteins to activate diverse intracellular signaling pathways. Endocrinology 141:4524-4532.
34. Cotta-Grand N, Rovère C, Guyon A, Cervantes A, Brau F,Nahon JL (2009) Melanin-concentrating hormone inducesneurite outgrowth in human neuroblastoma SH-SY5Y cellsthrough p53 and MAPKinase signaling pathways. Peptides30:2014-2024.
35. Oh ST, Liu QF, Jeong HJ, Lee S, Samidurai M, Jo J, Pak SC,Park HJ, Kim J, Jeon S (2019) Nasal cavity administration ofmelanin-concentrating hormone improves memory impairment in memory-impaired and Alzheimer's disease mousemodels. Mol Neurobiol 56:8076-8086.
36. Frodl T, Jäger M, Smajstrlova I, Born C, Bottlender R, Palladino T, Reiser M, Möller HJ, Meisenzahl EM (2008) Effect ofhippocampal and amygdala volumes on clinical outcomes inmajor depression: a 3-year prospective magnetic resonanceimaging study. J Psychiatry Neurosci 33:423-430.
37. Varas M, Pérez M, Monzón ME, de Barioglio SR (2002) Mela-nin-concentrating hormone, hippocampal nitric oxide levelsand memory retention. Peptides 23:2213-2221.
43. Sakurada K, Kato H, Nagumo H, Hiraoka H, Furuya K, Ikuhara T, Yamakita Y, Fukunaga K, Miyamoto E, Matsumura F,Matsuo YI, Naito Y, Sasaki Y (2002) Synapsin I is phosphorylated at Ser603 by p21-activated kinases (PAKs) in vitroand in PC12 cells stimulated with bradykinin. J Biol Chem277:45473-45479.
44. Banke TG, Bowie D, Lee H, Huganir RL, Schousboe A,Traynelis SF (2000) Control of GluR1 AMPA receptor function by cAMP-dependent protein kinase. J Neurosci 20:89-102.
45. Kameyama K, Lee HK, Bear MF, Huganir RL (1998) Involvement of a postsynaptic protein kinase A substrate in theexpression of homosynaptic long-term depression. Neuron21:1163-1175.
48. Ye H, Cui XY, Ding H, Cui SY, Hu X, Liu YT, Zhao HL, ZhangYH (2018) Melanin-concentrating hormone (MCH) andMCH-R1 in the Locus coeruleus may be involved in theregulation of depressive-like behavior. Int J Neuropsychopharmacol 21:1128-1137.
49. Urbanavicius J, Lagos P, Torterolo P, Scorza C (2014) Prodepressive effect induced by microinjections of MCH into thedorsal raphe: time course, dose dependence, effects on anxiety-related behaviors, and reversion by nortriptyline. BehavPharmacol 25:316-324.
50. Borowsky B, Durkin MM, Ogozalek K, Marzabadi MR,DeLeon J, Lagu B, Heurich R, Lichtblau H, Shaposhnik Z,Daniewska I, Blackburn TP, Branchek TA, Gerald C, VayssePJ, Forray C (2002) Antidepressant, anxiolytic and anorecticeffects of a melanin-concentrating hormone-1 receptor antagonist. Nat Med 8:825-830.
52. Smith DG, Hegde LG, Wolinsky TD, Miller S, Papp M, Ping X,Edwards T, Gerald CP, Craig DA (2009) The effects of stressful stimuli and hypothalamic-pituitary-adrenal axis activation are reversed by the melanin-concentrating hormone 1receptor antagonist SNAP 94847 in rodents. Behav Brain Res197:284-291.
53. Gehlert DR, Rasmussen K, Shaw J, Li X, Ardayfio P, Craft L,Coskun T, Zhang HY, Chen Y, Witkin JM (2009) Preclinicalevaluation of melanin-concentrating hormone receptor 1antagonism for the treatment of obesity and depression. JPharmacol Exp Ther 329:429-438.
54. Roy M, David N, Cueva M, Giorgetti M (2007) A study of theinvolvement of melanin-concentrating hormone receptor 1(MCHR1) in murine models of depression. Biol Psychiatry61:174-180.
55. Basso AM, Bratcher NA, Gallagher KB, Cowart MD, ZhaoC, Sun M, Esbenshade TA, Brune ME, Fox GB, Schmidt M,Collins CA, Souers AJ, Iyengar R, Vasudevan A, Kym PR,Hancock AA, Rueter LE (2006) Lack of efficacy of melaninconcentrating hormone-1 receptor antagonists in models ofdepression and anxiety. Eur J Pharmacol 540:115-120.
56. Oh ST, Liu QF, Jeong HJ, Lee S, Samidurai M, Jo J, Pak SC,Park HJ, Kim J, Jeon S (2019) Nasal cavity administration ofmelanin-concentrating hormone improves memory impairment in memory-impaired and Alzheimer's disease mousemodels. Mol Neurobiol 56:8076-8086.
57. Thorne RG, Pronk GJ, Padmanabhan V, Frey WH 2nd (2004)Delivery of insulin-like growth factor-I to the rat brain andspinal cord along olfactory and trigeminal pathways following intranasal administration. Neuroscience 127:481-496.