When I was doing my post on the function and identity of growth hormone secretagogues I learned that a type of common GHS is Ghrelin. I would suspect then that it is possible that Ghrelin can help contribute towards height and growth. I used wikipedia to learn more about ghrelin and this is what I found (from HERE)… (as always the most critical parts are highlighted)
Ghrelin is a 28 amino acid hunger-stimulating peptide and hormone that is produced mainly by P/D1 cells lining the fundus of the human stomach andepsilon cells of the pancreas.[1] Ghrelin levels increase before meals and decrease after meals. It is considered the counterpart of the hormone leptin, produced by adipose tissue, which induces satiation when present at higher levels. In some bariatric procedures, the level of ghrelin is reduced in patients, thus causing satiation before it would normally occur.[2]
Ghrelin is a potent stimulator of growth hormone from the anterior pituitary gland.[3] The ghrelin receptor is a G protein-coupled receptor, known as thegrowth hormone secretagogue receptor. Ghrelin binds to the GHSR1a splice-variant of this receptor which is present in high density in the hypothalamus, pituitary as well as vagal afferent cell bodies and vagal afferent endings throughout the gastro-intestinal tract.[4][5]
Ghrelin plays a significant role in neurotrophy, particularly in the hippocampus, and is essential for cognitive adaptation to changing environments and the process of learning.[6][7] Ghrelin has been shown to activate the endothelial isoform of nitric oxide synthase in a pathway that depends on various kinases including Akt.[8]
Me: It turns out the Ghrelin is a type of hormone/ peptide which we could call a growth hormone releasing hormone or GHRH, which is what the hypothalamus released to tell the pituitary to start releasing its own GH. From another section in the wikipedia article it seems to promote fetus growth. It is associated with leptin which has shown to be involved in height increase.
Interestingly Height Quest has already looked at the link between ghrelin and height HERE. He claims…
“Ghrelin promotes osteogenesis of intramembranous bone and improves the repair of calvarial bone defect in rats in vivo..” “Ghrelin is actually a chemical that can be modulated. Any activity that makes you hungry increases Ghrelin levels and any activity that makes you satiated decreases Ghrelin levels. Ghrelin being located in the proliferative zone of the epiphyseal growth plate means it very likely has height increasing effects. Other Ghrelin effects related to chondrocytes are promotin cAMP accumulation(along with sulfated proteoglycan & hyaluronate synthesis), regulating chondrocyte metabolism(increases proteoglycan synthesis and programmed cell death), upregulates chondroitin sulfate type IV(LSJL also upregulates chondroitin sulfate type IV), and decreases fatty acid uptake by chondrocytes.”
Me: My argument would be that ghrelin is both a cause and an effect. you can cause it to rise in level from certain actions, but it can also cause you to act in a certain way from the hunger trigger. In general, eating more leads to obesity which high levels of ghrelin is seen in. Given the eating patterns of humans and growth patterns, I would claim that Ghrelin is important for height gain during the puberty stages when the person is still growing but it has a negative effect after the person has reached physical maturity. From this study HERE you can see that low fasting levels of ghrelin is correlated with Seckel Syndrome which is a type of primordial dwarfism which can be helped out a little with GH injections. In my own personal experience, I would say that overall, people who are big eaters throughout their entire lifetime tend to be slightly taller than other people. Their overeating habits from ghrelin levels may have caused them to be overweight at adults and ultimately lead to height loss from loading issues. Compare this to people who became overweight only after having an overeating problem in adult hood and we can say that during the early years of development, Ghrelin may be critical in growth and height.
Ghrelin release has been shown to be related to morphine injections which suggest that it can be released from behavior that positively feedbacks on pleasure seeking behavior at least in childhood.
Study cited is below.
Growth hormone treatment, final height, insulin-like growth factors, ghrelin, and adiponectin in four siblings with Seckel syndrome.
Source
Department of Pediatrics, Aarhus University Hospital, Skejby, Aarhus, Denmark. nielbirk@rm.dk
Abstract
OBJECTIVE:
To report on the effect of growth hormone (GH) treatment on final height (FH) and to describe the insulin-like growth factor (IGF) system, ghrelin, and adiponectin (ADPN) in children with Seckel syndrome.
SUBJECTS AND RESULTS:
Four severely growth-retarded Iraqi siblings (two girls and two boys) with Seckel syndrome were referred at ages 16.5, 14.4, 12.4, and 10.4 years. They were born at term, but their growth was retarded and birth weight ranged between 1 and 1.5 kg. The children were healthy and had a normal response to GH provocative test. Long-term GH treatment of the youngest brother and sister increased the FH by 7.2 and 3.4 cm, respectively, compared with their older brother and sister. At FH, body mass index standard deviation scores (BMISDS) ranged from -3.0 to -3.9. Serum levels of immunoreactive IGF-1, bioactive IGF-1, and IGF-binding protein 3 were all within normal to high range before GH treatment and increased after GH treatment. Fasting plasma ghrelin remained severely reduced. Despite low BMISDS, plasma ADPN was moderately reduced and showed an almost complete absence of the low-molecular-weight subform.
CONCLUSION:
This is the first report on the effect of GH treatment on FH in children with Seckel syndrome. GH may have increased FH. In addition to growth defects and reduced BMISDS, patients with Seckel syndrome are characterized by low fasting ghrelin levels, low total ADPN, and near deficiency of the low-molecular-weight ADPN subform. The possible significance of the hormonal changes requires further investigations.
- PMID: 22308854 [PubMed – indexed for MEDLINE]
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