Unit 3 Day 16 Learning objectives

metabolism definition

structures and processes coordinated in space + time

chemical reactions that sustain life

metabolism pathway

brain senses hunger/satiety

organism eats/digests

cells process food into usable energy (cellular respiration)

cellular and physio. functions (eg. DNA repair, homeostasis)

metabolism overview

gut brain connections

similar hormones produces in gut + brain

hormone produced in gut (stim. by ingestion) impact hormone prod. in brain

brain to gut axis (influence on)

motility

secretion

nutrient delivery

microbial balance

gut to brain axis (influence on)

neurotransmitters

stress/anxiety

mood

behavior

regulation of feeding

brain takes in info. from surroundings (sensory) + periphery (body physios.)

integrates signals

makes decisions on what + when to eat

center’s influence on appetite

orexigenic center stimulates

anorexigenic center inhibits

feeding regulator hormones

neuroPeptide Y (NPY)

galanin

orexin

ghrelin

leptin

insulin

cholecystokinin (CCK)

cocaine-amphetamine-regulated transcript (CART)

cortisol

orexigenic hormones produced in brain

neuropeptide Y (NPY)

ghrelin

galanin

orexin

hormones that reg. feeding produced outside of brain

ghrelin (O)

leptin (A)

insulin (A)

cholecystokinin (CCK) (A)

cortisol (A)

neuropeptide y (NPY) structure

36 aa

neuropeptide y (NPY) produced in

hypothalamus + nerve fibers in S. Int

neuropeptide y (NPY) O or A

orexigenic (stimulates)

galanin structure

29 aa

galanin produced in

CNS (hypo + pit.) + GI Tract

galanin O or A

orexigenic (stimulates)

orexin structure

neuropeptide (isoforms)

28, 33, 34 aa

pre-pro hormone

orexin produced in

hypothalamus

orexin O or A

orexigenic

ghrelin structure

28 aa

N-end fatty acid chain

peptide

ghrelin produced in

stomach/anterior gut

hypothalamus

(targets brain)

ghrelin O or A

orexigenic

leptin structure

167 aa peptide

leptin produced by

white adipose tissue (fat)

(targets the hypothalamus)

leptin O or A

anorexigenic

leptin function

signal of whole body energy levels (fat)

insulin structure

A (21 aa) + B (30 aa) peptide chains linked by disulfide bonds

insulin produced by

pancreatic beta cells

insulin O or A

anorexigenic (at high concentrations)

insulin function

signals the body has incoming fuel + doesn’t need to eat more

cholecystokinin (CCK) structure

pre-pro peptide

several diff. length isoforms (58, 33, 22, 8)

mature (bioactive) form has sulfate group (-SO3)

cholecystokinin (CCK) produced by

gut (duodenum) + brain

cholecystokinin (CCK) O or A

anorexigenic

(in response to food in GI tract)

cortisol structure

steroid-based

cortisol secreted by

adrenal cortex in response from ACTH from pit. + CRH from hypothal.

cortisol O or A

anorexigenic

cortisol function

metabolize stored energy

released in response to stress

cocaine-amphetamine-regulated transcript (CART) structure

neuropeptide

several lengths produced (41 aa)

cocaine-amphetamine-regulated transcript (CART) produced in

brain + intestines

cocaine-amphetamine-regulated transcript (CART) function

works synergistically with CCK