title: Energy expenditure and aging.
abstract: The study of energy expenditure (EE) has deep roots in understanding aging and lifespan in all species. In humans, total EE decreases substantially in advanced age resulting from parallel changes in resting metabolic rate (RMR) and activity EE. For RMR, this reduction appears to be due to a reduction in organ mass and specific metabolic rates of individual tissues. However, these anatomical changes explain very little regarding the decline in activity EE, which is governed by both genetic and environmental sources. The biological control centers for activity EE are closely coupled with body mass fluctuations and seem to originate in the brain. Several candidate neuromodulators may be involved in the age-related reduction of activity EE that include: orexin, agouti-related proteins and dopaminergic pathways. Unfortunately, the existing body of research has primarily focused on how neuromodulators influence weight gain and only a few studies have been performed in aging models. Recent evidence suggests that activity EE has an important role in dictating lifespan and thus places emphasis on future research to uncover the underlying biological mechanisms. The study of EE continues to unlock clues to aging.
authors.affiliation: University of Florida, Institute on Aging, Department of Aging and Geriatric Research, 210 E Mowry Rd, PO Box 112610, Gainesville, FL 32611-2610, United States. tmanini@aging.ufl.edu
authors.forename: Todd M
authors.initials: TM
authors.lastname: Manini
mesh_terms: D000375:Aging / Q000378:metabolism*; D054369:Agouti-Related Protein / Q000378:metabolism*; D001823:Body Composition; D015992:Body Mass Index; D001835:Body Weight / Q000502:physiology; D004298:Dopamine / Q000378:metabolism*; D004734:Energy Metabolism / Q000502:physiology*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D008136:Longevity; D009479:Neuropeptides / Q000378:metabolism*; D000068797:Orexins; D015430:Weight Gain
chemical_list: D054369:Agouti-Related Protein; D047908:Intracellular Signaling Peptides and Proteins; D009479:Neuropeptides; D000068797:Orexins; D004298:Dopamine
references.citation: Curr Opin Clin Nutr Metab Care. 2008 Jan;11(1):45-9
references.pmid: 18090658
references.citation: Eur J Neurosci. 2006 May;23(10):2677-85
references.pmid: 16817870
references.citation: J Cell Physiol. 1985 Jun;123(3):410-6
references.pmid: 2580848
references.citation: J Gerontol A Biol Sci Med Sci. 2001 Oct;56 Spec No 2:65-80
references.pmid: 11730239
references.citation: Exp Gerontol. 1985;20(5):253-63
references.pmid: 2419151
references.citation: J Exp Biol. 2005 May;208(Pt 9):1717-30
references.pmid: 15855403
references.citation: J Appl Physiol (1985). 2004 Apr;96(4):1357-64
references.pmid: 14660509
references.citation: J Gerontol. 1956 Jul;11(3):298-300
references.pmid: 13332224
references.citation: Biochem Biophys Res Commun. 1998 Dec 18;253(2):241-5
references.pmid: 9878522
references.citation: Am J Physiol Regul Integr Comp Physiol. 2008 Sep;295(3):R773-80
references.pmid: 18596107
references.citation: BMJ. 2009 Mar 05;338:b688
references.pmid: 19264819
references.citation: Osteoporos Int. 1993 May;3(3):154-9
references.pmid: 8481592
references.citation: J Gerontol B Psychol Sci Soc Sci. 1996 Jan;51(1):S30-41
references.pmid: 8548521
references.citation: Nature. 2005 Apr 28;434(7037):1087-92
references.pmid: 15858564
references.citation: Diabetologia. 1984 Jul;27(1):13-6
references.pmid: 6147290
references.citation: Mech Ageing Dev. 1985 Dec;33(1):11-7
references.pmid: 3001440
references.citation: J Clin Endocrinol Metab. 1997 Oct;82(10):3208-12
references.pmid: 9329340
references.citation: Eur J Clin Nutr. 2000 Jun;54 Suppl 3:S92-103
references.pmid: 11041080
references.citation: Am J Physiol Regul Integr Comp Physiol. 2008 Mar;294(3):R699-710
references.pmid: 18160530
references.citation: J Clin Endocrinol Metab. 1993 Apr;76(4):1054-7
references.pmid: 8386182
references.citation: J Nutr Health Aging. 1998;2(2):115-8
references.pmid: 10993580
references.citation: J Appl Physiol (1985). 1986 Dec;61(6):2162-7
references.pmid: 3027022
references.citation: J Clin Endocrinol Metab. 1996 Sep;81(9):3239-43
references.pmid: 8784075
references.citation: Exp Gerontol. 1970 Apr;5(1):83-92
references.pmid: 5446387
references.citation: Proc Natl Acad Sci U S A. 1993 Jun 1;90(11):5044-6
references.pmid: 8506349
references.citation: J Appl Physiol. 1955 May;7(6):704-10
references.pmid: 14381351
references.citation: J Nutr. 2002 Jun;132(6 Suppl 2):1583S-97S
references.pmid: 12042467
references.citation: Age Ageing. 1989 May;18(3):158-67
references.pmid: 2675579
references.citation: Am J Physiol Endocrinol Metab. 2007 Apr;292(4):E1207-12
references.pmid: 17401138
references.citation: JAMA. 2006 Jul 12;296(2):171-9
references.pmid: 16835422
references.citation: Neuroendocrinology. 2008;87(2):71-90
references.pmid: 17984627
references.citation: Med Sci Sports Exerc. 2008 Jan;40(1):181-8
references.pmid: 18091006
references.citation: Eur J Clin Nutr. 2005 Feb;59(2):255-62
references.pmid: 15494736
references.citation: Neurosci Lett. 2002 Nov 8;332(3):190-4
references.pmid: 12399012
references.citation: Am J Physiol. 1992 Nov;263(5 Pt 1):E950-7
references.pmid: 1443128
references.citation: Am J Physiol. 1984 Nov;247(5 Pt 2):R850-5
references.pmid: 6093604
references.citation: J Neurosci. 2002 Oct 15;22(20):8850-9
references.pmid: 12388591
references.citation: Obes Res. 2001 Jun;9(6):368-79
references.pmid: 11399784
references.citation: Am J Physiol. 1995 Nov;269(5 Pt 1):E820-6
references.pmid: 7491931
references.citation: Am J Clin Nutr. 1995 Mar;61(3):473-81
references.pmid: 7872209
references.citation: J Appl Physiol (1985). 2008 Aug;105(2):495-501
references.pmid: 18556430
references.citation: J Clin Invest. 1986 Dec;78(6):1568-78
references.pmid: 3782471
references.citation: Am J Physiol. 1995 Mar;268(3 Pt 2):R641-50
references.pmid: 7900906
references.citation: J Appl Physiol (1985). 2003 Jun;94(6):2368-74
references.pmid: 12598481
references.citation: Am J Physiol Endocrinol Metab. 2001 Sep;281(3):E633-9
references.pmid: 11500320
references.citation: Am J Clin Nutr. 2005 Oct;82(4):901-8
references.pmid: 16210723
references.citation: Int J Obes Relat Metab Disord. 2000 Jun;24(6):742-50
references.pmid: 10878681
references.citation: J Appl Physiol (1985). 2003 Oct;95(4):1728-36
references.pmid: 12970378
references.citation: Gerontology. 1989;35(1):36-57
references.pmid: 2656413
references.citation: Nutr Rev. 2000 Mar;58(3 Pt 1):61-6
references.pmid: 10812919
references.citation: Free Radic Biol Med. 2000 Nov 15;29(10):946-68
references.pmid: 11084284
references.citation: Metabolism. 1997 Dec;46(12):1412-7
references.pmid: 9439535
references.citation: J Clin Endocrinol Metab. 1996 Oct;81(10):3469-75
references.pmid: 8855787
references.citation: J Gerontol. 1991 Mar;46(2):B47-53
references.pmid: 1997563
references.citation: Am J Clin Nutr. 1989 Dec;50(6):1314-23
references.pmid: 2596423
references.citation: J Appl Physiol (1985). 1986 Nov;61(5):1656-60
references.pmid: 3781978
references.citation: Pharmacol Biochem Behav. 1985 Mar;22(3):461-8
references.pmid: 3991761
references.citation: J Gerontol A Biol Sci Med Sci. 2001 Oct;56 Spec No 2:81-8
references.pmid: 11730241
references.citation: Mech Ageing Dev. 1976 Sep-Oct;5(5):347-70
references.pmid: 823384
references.citation: Neurobiol Aging. 1997 Jan-Feb;18(1):57-66
references.pmid: 8983033
references.citation: Am J Hum Biol. 1993;5(3):291-296
references.pmid: 28548411
references.citation: Behav Genet. 1997 Jul;27(4):389-99
references.pmid: 9519564
references.citation: Biochem Biophys Res Commun. 1997 Aug 28;237(3):629-31
references.pmid: 9299416
references.citation: J Gerontol A Biol Sci Med Sci. 1998 May;53(3):M235-41
references.pmid: 9597057
references.citation: Med Sci Sports Exerc. 2000 Sep;32(9):1623-9
references.pmid: 10994915
references.citation: Med Sci Sports Exerc. 2000 Sep;32(9):1601-9
references.pmid: 10994912
references.citation: Am J Physiol. 1996 Oct;271(4 Pt 1):C1380-9
references.pmid: 8897845
references.citation: Thorax. 1997 Sep;52(9):780-5
references.pmid: 9371208
references.citation: Mech Ageing Dev. 1976 Sep-Oct;5(5):371-87
references.pmid: 823385
references.citation: Cell Metab. 2005 Dec;2(6):421-7
references.pmid: 16330327
references.citation: N Engl J Med. 1993 Feb 25;328(8):538-45
references.pmid: 8426621
references.citation: Neurobiol Aging. 2007 Aug;28(8):1286-95
references.pmid: 16870307
references.citation: J Gerontol. 1992 Jul;47(4):M99-105
references.pmid: 1624697
references.citation: Muscle Nerve. 2007 Mar;35(3):354-62
references.pmid: 17143881
references.citation: Am J Clin Nutr. 1997 Oct;66(4):774-86
references.pmid: 9322550
references.citation: J Gerontol A Biol Sci Med Sci. 2001 Oct;56 Spec No 2:7-12
references.pmid: 11730240
references.citation: J Appl Physiol (1985). 2009 Jun;106(6):1780-4
references.pmid: 19325028
references.citation: Exp Gerontol. 2008 Dec;43(12):1069-76
references.pmid: 18852040
references.citation: Am J Physiol Endocrinol Metab. 2006 Aug;291(2):E381-7
references.pmid: 16507602
references.citation: Ann Epidemiol. 1999 Nov;9(8):481-8
references.pmid: 10549881
references.citation: J Nutr. 1991 Dec;121(12):1990-8
references.pmid: 1941263
references.citation: Cell. 1999 Aug 20;98(4):437-51
references.pmid: 10481909
references.citation: Am J Public Health. 1971 Jul;61(7):1362-70
references.pmid: 5563255
references.citation: Am J Epidemiol. 2009 Jun 15;169(12):1507-16
references.pmid: 19383938
references.citation: Am J Clin Nutr. 1997 Oct;66(4):880-9
references.pmid: 9322564
references.citation: Physiol Rev. 1997 Jul;77(3):731-58
references.pmid: 9234964
references.citation: Science. 1999 Jan 8;283(5399):212-4
references.pmid: 9880251
references.citation: Am J Physiol. 1986 May;250(5 Pt 2):R823-30
references.pmid: 3085521
references.citation: J Appl Physiol (1985). 2009 Jun;106(6):1759-60
references.pmid: 19359616
references.citation: Am J Clin Nutr. 2000 Aug;72(2):355-60
references.pmid: 10919927
references.citation: Redox Rep. 2007;12(1):91-5
references.pmid: 17263918
references.citation: Metabolism. 1989 Apr;38(4):364-70
references.pmid: 2657322
references.citation: Ann N Y Acad Sci. 1994 May 31;719:129-35
references.pmid: 8010587
references.citation: Nephrol Dial Transplant. 2004 Dec;19(12):3091-7
references.pmid: 15507474
references.citation: Eur J Clin Nutr. 1996 Feb;50(2):72-92
references.pmid: 8641250
references.citation: Obes Res. 1995 Sep;3(5):435-46
references.pmid: 8521163
references.citation: Obesity (Silver Spring). 2007 Dec;15(12):2964-73
references.pmid: 18198305
references.citation: N Engl J Med. 1995 Mar 9;332(10):621-8
references.pmid: 7632212
references.citation: Am J Physiol. 1993 Mar;264(3 Pt 1):E450-5
references.pmid: 8460693
references.citation: Metabolism. 1996 Aug;45(8):992-7
references.pmid: 8769358
references.citation: Brain Res. 2000 Aug 4;873(1):181-7
references.pmid: 10915829
references.citation: Diabetes. 2007 Jun;56(6):1615-22
references.pmid: 17351147
references.citation: J Appl Physiol (1985). 1997 Jul;83(1):229-39
references.pmid: 9216968
references.citation: Physiol Behav. 1997 Jul;62(1):97-103
references.pmid: 9226348
references.citation: Am J Clin Nutr. 2005 Dec;82(6):1253-9
references.pmid: 16332658
references.citation: Med Sci Sports Exerc. 2001 Jun;33(6 Suppl):S370-8; discussion S419-20
references.pmid: 11427762
references.citation: Brain Res. 1990 Jan 1;506(1):46-52
references.pmid: 2154278
references.citation: Am J Physiol Endocrinol Metab. 2002 Jan;282(1):E132-8
references.pmid: 11739093
references.citation: FASEB J. 2006 Apr;20(6):768-9
references.pmid: 16464955
references.citation: J Appl Physiol (1985). 1992 Nov;73(5):1815-9
references.pmid: 1474056
references.citation: Am J Physiol. 1987 Jul;253(1 Pt 2):R1-7
references.pmid: 3605374