Volume 4 • Issue 3 • 1000e139
Biochem Physiol
ISSN: 2168-9652 BCP, an open access journal
Editorial Open Access
Biochemistry & Physiology: Open Access
Rashid et al., Biochem Physiol 2015, 4:3
http://dx.doi.org/10.4172/2168-9652.1000e139
Keywords: Ghrelin; Growth hormone; Neurotransmitter;
Neuroscience
Editorial
Ghrelin, the hunger hormone is a type of peptide hormone secreted
by the ghrelinergic cells located throughout the GIT mostly from
stomach & a lesser extent from duodenum. It acts as a neuropeptide
in the CNS. Besides regulating appetite it also plays a signiicant
role in regulating distribution and rate of use of energy. Ghrelin act
as G-protein coupled receptor (GPCR) named Growth hormone
secretagogue receptor (GHSR) or ghrelin receptor. It has 28 amino
acids and containing an n-octanoyl group in the serine residue at
position 3 [1-6]. It is reported that ghrelin is performed its action into
various types of tissues such as duodenum, jejunum, ileum, colon, lung,
heart, pancreas, kidney, testis, pituitary, and hypothalamus in the body
system, moreover in the CNS system it expressed at low level [7-9].
Recent indings revealed that administration of ghrelin to rats
induces food intake and reduction of energy expenses [10-14]. he
major physiological and biological function of ghrelin includes growth
hormone secretion, stimulation of food intake, gastric acid secretion,
regulation of motility and the regulation of the endocrine and exocrine
pancreatic secretions.
Ater crossing the blood-brain barrier ghrelin reaches in brainstem
[17], and transmits its signal through the vagal nerve [18]. In
hypothalamus, it activates the arcuate nucleus (ARC), paraventricular
nucleus (PVN), dorsomedial region, central nucleus of amygdala, and
the nucleus of solitary tract [19-20]. By stimulating the activity of
NPY/AGRP neurons and decreasing the activity of POMC and CART
neurons, ghrelin increases appetite and food intake [21-23]. AMPK is
regulates the fuel availability by stimulating ATP producing pathways
and inhibiting ATP consuming pathways [24]. Ater ATP depletion,
AMP rises and induces the activation of AMPK by phosphorylation
[25]. Activated AMPK then induces the phosphorylation of acetyl-CoA
carboxylase (ACC), which leading to the inhibition of ACC activity and
the decrease in malonyl-CoA levels and inally resulting in increased
fatty acid oxidation via the activation of carnitine-palmitoyl transferase
1 (CPT1) [26-27] (Figure 1).
*Corresponding author: M Salahuddin, Faculty of Medicine, University
of Hongkong, Pokfulam Road, Hongkong, Tel: +852-5584-1096; E-mail:
ssdin23@gmail.com
Received July 25, 2015; Accepted July 25, 2015; Published August 01, 2015
Citation: Rashid M, Islam MS, Salahuddin M, Sayfullah M, Hossain D, et al.
(2015) The Biochemistry of Hunger Stimulating Hormone: Why Understanding
This Cascade In Hypothalamus Is Beneicial. Biochem Physiol 4: e139. doi:
10.4172/2168-9652.1000e139
Copyright: © 2015 Rashid M, et al. This is an open-access article distributed under
the terms of the Creative Commons Attribution License, which permits unrestricted
use, distribution, and reproduction in any medium, provided the original author and
source are credited.
The Biochemistry of Hunger Stimulating Hormone: Why Understanding This
Cascade In Hypothalamus Is Beneficial
Mahjabin Rashid
1
, Md. Shariful Islam
2
, M Salahuddin
3
*, Md. Sayfullah
4
, Deluwer Hossain
5
, MA Momin
6
, M. Abu Sayed
7
, Jay Prakash Sah
8
and
Sanjay Kumar Shah
9
1
College of Medicine, Mymensingh Medical College and Hospital, Mymensingh, University of Dhaka, Bangladesh
2
Department of Biotechnology and Genetic Engineering, Faculty of Life Science, Mawlana Bhashani Science and Technology University, Tangail-1902, Bangladesh
3
Faculty of Medicine, University of Hongkong, Pokfulam Road, Hongkong
4
College of Medicine, Shaheed Ziaur Rahman Medical College Hospital, Bogra, University of Rajshahi, Bangladesh
5
Department of Pharmacology, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
6
Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
7
Department of Biochemistry and Molecular Biology, Hajee Mohammad Danesh Science and Technology University, Dinajpur-5200, Bangladesh
8
Department of Medical Laboratory Science, School of Health and Allied Sciences, Pokhara University, Lekhnath -12 Kaski, Nepal
9
Department of Medical Laboratory Science, Asian College for Advance Study, Satodobato, Lalitpur, Nepal
Abstract
Ghrelin is the key hormone responsible for our hunger stimulate to food intake in body system. At present a
huge number of people suffer from obesity, so understanding the mechanisms by which various hormones and
neurotransmitters have inluence on energy balance has been a subject of current research in neuroscience. At present
ghrelin is the only known gastrointestinal hormone that increases food intake where Plasma ghrelin levels are inversely
correlated with body weight and rise following weight loss in humans. It is a natural ligand of the growth hormone
(GH) secretagogue (GHS) receptor type 1a (GHS-R1a). The GHS-R is highly expressed in the hypothalamus, but is
also found in the brainstem, pituitary, GI tract, adipose tissue and other peripheral tissues. Ghrelin is still recognized
as a potential drug target for weight regulation. The main objective of this is to summarize the current knowledge and
optimize about the physiology and pathophysiology of ghrelin in food intake regulation.
Figure 1: Pathways involved in ghrelin induction of food intake in hypothalamus.
In this igure Arrows and lines indicate stimulation and inhibition [15,16].