energy balance and reproduction - lehigh university · 2011. 10. 3. · recommended publications...
TRANSCRIPT
-
Energy Balance and Reproduction
BioScience in the 21st Century Candice M. Klingerman
03 October 2011
-
Outline
• Energy balance • Sex and food in conflict • Sex and ingestive behavior • Motivation is more sensitive to energy
than performance
• Chemical messengers affect sex and ingestive behavior
-
Outline
• Energy balance • Sex and food in conflict • Sex and ingestive behavior • Motivation is more sensitive to energy
than performance
• Chemical messengers affect sex and ingestive behavior
-
Energetic Demands
• Cells need a constant supply of energy • Cannot eat all of the time. Need time for
other activities: – Foraging for food – Mating, caring for offspring – Defending territory, working
• Energy is not constantly available so must be able to store
-
Energy Balance
Food Intake
Energy Expenditure
• Cellular processes • Thermoregulation • Activity • Growth • Immune function • Reproduction
Energy Storage
• Internally (fat, muscle) • Externally (hoard)
Adapted from Schneider 2007
-
Food
• Energy is acquired from food • Food consists of macronutrients
– Fat – Carbohydrates – Protein
• Fat & carbohydrates free fatty acids & glucose – Free fatty acids and glucose energy (ATP)
Oxidized
-
Food
Macronutrients
Metabolic Fuels
Glucose oxidation
Fatty acid oxidation
ATP Adapted from Schneider 2007
(Fat, carbs, protein)
-
Adapted from Schneider, 2007
-
Block Fuel Oxidation Food Intake
Darling and Ritter, 2009
Fatty Acids Glucose
-
Food Intake Signals
• Primary sensory signals – Gut distention – Vagus nerve
• Secondary sensory signals – Hormones and neuropeptides that affect food
intake
-
Central Sensors
• Hypothalamus is important, but not required for control of food intake – Decerebrate rats still increase food intake in response to
inhibitors of metabolic fuel oxidation
• Caudal brainstem – Similar inhibitors increase food intake when injected into the 4th, but not 3rd ventricle – Lesions to area postrema and nucleus of the tractus solitarus attenuate effects of oxidation inhibitors
-
Peripheral Sensors
• Liver – Vagotomy abolishes the effect of a fatty acid oxidation
inhibitor (but not glucose inhibitor) on increasing food intake
– ATP storage
• Gut – Contains mechanoreceptors – Ghrelin
• Fat – Leptin
-
Leptin Ghrelin
Kollias, 2011
-
Energetic Demands
• Cells need a constant supply of energy • Cannot eat all of the time. Need time for
other activities – Foraging for food – Mating, caring for offspring – Defending territory, working
• Energy is not constantly available so must be able to store
-
Outline
• Energy balance • Sex and food in conflict • Sex and ingestive behavior • Motivation is more sensitive to energy
than performance
• Chemical messengers affect sex and ingestive behavior
-
Behaviors in Conflict
Sex Food
Mechanism(s)?
-
Sex Behavior
• Courtship – Scent marking
• Flank and vaginal – Spending time with an opposite-sex conspecific – Hopping and darting
• Mating – Lordosis – Presentation of rump – Male hit rate (I/M)
-
Lordosis in the Syrian Hamster
-
Ingestive Behavior
• Foraging • Eating • Hoarding
– Humans vs hamsters
Tom, 1983
-
Motivation & Performance
Vaginal marking
Time spent with a male vs. food
Lordosis
Food hoarding
Eating, Food Intake
Motivation
Performance
Ingestive Sexual
-
Outline
• Energy balance • Sex and food in conflict • Sex and ingestive behavior • Motivation is more sensitive to energy
than performance
• Chemical messengers affect sex and ingestive behavior
-
Food Restriction Dissociated SEXUAL Motivation From Performance
Klingerman et al., 2011
Performance
Days of Food Restriction Days of Re-feeding
Motivation
* Different at P < 0.05
=TIME SIGNIFICANTLY LOWER THAN AD LIB
Food Male
Home
-
Food Restriction Dissociated INGESTIVE Motivation from Performance
Klingerman et al., 2011
N.S.
Performance
Days of Food Restriction Days of Re-feeding
Motivation
* Different at P < 0.05
=TIME SIGNIFICANTLY LOWER THAN AD LIB
-
Motivation Clearly Dissociated from Performance
Mild food restriction significantly: • Food hoarding • Preference for males vs. food Has no effect on: • Frequency or duration of lordosis • Food intake (90 min or daily)
-
Outline
• Energy balance • Sex and food in conflict • Sex and ingestive behavior • Motivation is more sensitive to energy
than performance
• Chemical messengers affect sex and ingestive behavior
-
Things that Affect Sex & Ingestive Behaviors
• Energy restriction or deprivation – Block glucose oxidation (2DG, 5TG) – Block fatty acid oxidation (MP, MA)
• Chemical messengers – Food: Neuropeptide Y, ghrelin, insulin, GnIH – Sex: Leptin, estradiol, GnRH
-
Sex Food
Food Sex Chemical Messenger
• Ghrelin
• Gonadotropin-inhibiting hormone
• Leptin
• Estradiol
-
Ghrelin
• Produced and secreted from cells in the stomach and pancreas in response to the absence of food
• Is also produced/secreted from the arcuate nucleus of the hypothalamus and controls growth hormone secretion from the pituitary
-
Circulating Ghrelin with Fasting
Fasting
Keen-Rhinehart and Bartness, 2004
-
Injections of Ghrelin Food Intake and Sex Behavior
Small et al., 2000; Shah and Nyby, 2010
Food intake Sex behavior
-
Sex Food
Food Sex Chemical Messenger
• Ghrelin
• Gonadotropin-inhibiting hormone
• Leptin
• Estradiol
-
Leptin
• Produced/secreted from adipocytes • Found in proportion to body fat • Mutations in leptin or its receptor lead to
hyperphagia and obesity
O’Rahilly et al., 2003
-
Circulating Leptin with Fasting
Fasting
12 h Fast 24 h Fast
Schneider, Blum, and Wade, 2000
-
Injections of Leptin Sex Behavior
Sexual performance
Schneider et al., 2007
Vaginal scent marking
-
Injections of Leptin Ingestive Behavior
Food intake
Schneider et al., 2007; Mistry et al., 1997
Food hoarding
No leptin
-
Sex Food
Food Sex Chemical Messenger
• Ghrelin
• Gonadotropin-inhibiting hormone
• Leptin
• Estradiol
-
Gonadotropin-inhibiting Hormone (GnIH)
• Released from dorsomedial nucleus of the hypothalamus
• May be involved in regulating reproductive cycles of seasonal breeding birds and mammals
-
Circulating GnIH with Fasting
Fasting
Klingerman, Williams et al., in review
-
Injections of GnIH Ingestive Behavior Sex Behavior
Food intake Sex behavior
Johnson et al., 2007; Bentley et al., 2006
-
Sex Food
Food Sex Chemical Messenger
• Ghrelin
• Gonadotropin-inhibiting hormone
• Leptin
• Estradiol
-
Estradiol
• A hormone secreted from the ovary • Circulating levels increase as ovulation is
approaching
• Regulates sex behavior
-
Circulating Estradiol Food intake
Fessler, 2003
Estradiol rising Estradiol rising
Calo
ric
inta
ke
-
Injections of Estradiol Food intake
Asarian and Geary, 2002
-
Injections of Estradiol Sex Behavior
Vaginal Marking Lordosis
Freq
uenc
y of
Vag
inal
Mar
ks
Lisk and Nachtigall, 1988; Meisel et al., 1988
-
Sex Food
Food Sex Chemical Messenger
• Ghrelin
• Gonadotropin-inhibiting hormone
• Leptin
• Estradiol
-
Summary
• Cells need a constant supply of energy. – We cannot eat all of the time – Mechanism(s) capable of monitoring internal and
external energy. Peptide systems?
• Sex and ingestive behaviors are affected by energy. Motivation more sensitive than performance
• Chemical messengers that ingestive behavior, sex behavior
-
Take Home Message:
Food
Sex
Food
Sex
-
Recommended Publications
Klingerman CM, Krishnamoorthy K, Patel K, Spiro AB, Struby C, Patel A, Schneider JE. Energetic challenges unmask the role of ovarian hormones in orchestrating ingestive and sex behaviors. Hormones and Behavior 2010; 58:563-74.
Klingerman, CM, Patel, A, Hedges, VL, Meisel, RL, and Schneider., JE. Food restriction dissociates sexual motivation, sexual
performance, and the rewarding consequences of copulation in female Syrian hamsters.” Behavioral Brain Research 2011; 223:356-370.
Wade GN. and Schneider JE. Metabolic fuels and reproduction in female mammals. Neuroscience and Biobehavioral Reviews. 1992; 16:235-272.
Jones JE, Pick RR, Dettloff SL, Wade GN. Metabolic fuels, neuropeptide Y, and estrous behavior in Syrian hamsters. Brain Research. 2004; 1007:78-85.
Morin LP. Effects of various feeding regimens and photoperiod or pinealectomy on ovulation in the hamster. Biology of Reproduction 1975; 13:99-103.
Food
Sex
/ColorImageDict > /JPEG2000ColorACSImageDict > /JPEG2000ColorImageDict > /AntiAliasGrayImages false /CropGrayImages true /GrayImageMinResolution 300 /GrayImageMinResolutionPolicy /OK /DownsampleGrayImages true /GrayImageDownsampleType /Bicubic /GrayImageResolution 300 /GrayImageDepth -1 /GrayImageMinDownsampleDepth 2 /GrayImageDownsampleThreshold 1.50000 /EncodeGrayImages true /GrayImageFilter /DCTEncode /AutoFilterGrayImages true /GrayImageAutoFilterStrategy /JPEG /GrayACSImageDict > /GrayImageDict > /JPEG2000GrayACSImageDict > /JPEG2000GrayImageDict > /AntiAliasMonoImages false /CropMonoImages true /MonoImageMinResolution 1200 /MonoImageMinResolutionPolicy /OK /DownsampleMonoImages true /MonoImageDownsampleType /Bicubic /MonoImageResolution 1200 /MonoImageDepth -1 /MonoImageDownsampleThreshold 1.50000 /EncodeMonoImages true /MonoImageFilter /CCITTFaxEncode /MonoImageDict > /AllowPSXObjects false /CheckCompliance [ /None ] /PDFX1aCheck false /PDFX3Check false /PDFXCompliantPDFOnly false /PDFXNoTrimBoxError true /PDFXTrimBoxToMediaBoxOffset [ 0.00000 0.00000 0.00000 0.00000 ] /PDFXSetBleedBoxToMediaBox true /PDFXBleedBoxToTrimBoxOffset [ 0.00000 0.00000 0.00000 0.00000 ] /PDFXOutputIntentProfile () /PDFXOutputConditionIdentifier () /PDFXOutputCondition () /PDFXRegistryName () /PDFXTrapped /False
/CreateJDFFile false /Description > /Namespace [ (Adobe) (Common) (1.0) ] /OtherNamespaces [ > /FormElements false /GenerateStructure false /IncludeBookmarks false /IncludeHyperlinks false /IncludeInteractive false /IncludeLayers false /IncludeProfiles false /MultimediaHandling /UseObjectSettings /Namespace [ (Adobe) (CreativeSuite) (2.0) ] /PDFXOutputIntentProfileSelector /DocumentCMYK /PreserveEditing true /UntaggedCMYKHandling /LeaveUntagged /UntaggedRGBHandling /UseDocumentProfile /UseDocumentBleed false >> ]>> setdistillerparams> setpagedevice