Ghrelin,
obestatin are peptides that play a vital role in maintaining energy
homeostasis. Eating disorders such as anorexia nervosa and bulimia nervosa
hamper the secretion of these peptides.
Neuropeptide
Y (NPY) is a peptide neurotransmitter that is found in autonomic nervous system
and brain and is concerned with energy regulation. Peptide YY (PYY) is a
protein released by the cells of colon and ileum. In human beings it reduces
the appetite. Peptide YY (PYY) is also known as peptide tyrosine tyrosine or
pancreatic peptide YY3-36.
Dana
Sedlackova and colleagues conducted a study that was published in the journal
BMC Nutrition and Metabolism, 2012, to compare the effect of high carbohydrate
and high protein breakfast on plasma ghrelin, obestatin, NPY and PYY in women
with anorexia nervosa and bulimia.
The plasma levels of gut-brain axis peptides ghrelin, obestatin, NPY
and PYY were recorded after the intake of high-protein and high-carbohydrate
breakfast in healthy controls and in patients with anorexia nervosa and
bulimia.
The
plasma hormone levels were determined by RIA kits and blood samples were taken
from the cubital vein. The first blood sample was taken before breakfast and
then after 30, 60, 90,120 and 150 minutes after the intake of breakfast.
The
scientists observed that plasma ghrelin levels were increased in anorexia
nervosa patients while fasting and post-prandial plasma obestatin levels were
raised in both bulimia and anorexia nervosa patients. After breakfast, the
plasma levels of ghrelin and obestatin decreased but were still above the range of normal healthy controls. In
anorexia nervosa and bulimia patients, the levels of neuropeptide Y (NPY) were
recorded high and it did not change postprandially.
After
the intake of a high protein breakfast the peptide YY (PYY) levels increased in
bulimia nervosa and anorexia nervosa patients. In all the groups the reactions
to breakfast were identical for obestatin and neuropeptideY (NPY) while the
reactions were different for ghrelin and peptide YY (PYY).
It
was concluded that different reactions to breakfast for peptide YY (PYY) and
ghrelin are indicative of the role these hormones play in energy homeostasis
regulation and it can be used in managing acute eating disorders. In anorexia
nervosa and bulimia nervosa patients, obestatin and neuropeptide Y (NPY) act as
eating disorder markers.
Reference:
Comparison of a high-carbohydrate and
high-protein breakfast effect on plasma ghrelin, obestatin, NPY and PYY levels
in women with anorexia and bulimia nervosa; Dana Sedlackova et al; Nutrition
and Metabolism 2012
Source-Medindia