Grehlin anybody want to educate us?

voner

Senior Member
Messages
592
So I ran across the reference to Grehlin and Wikipedia:

http://en.wikipedia.org/wiki/Ghrelin

to me -- it seems like Grehlin is involved in a many of the things that go wrong in CFS/fms

for example (from Wikipedia):


Gastrointestinal tract

Ghrelin has been proposed as a hormone which promotes intestinal cell proliferation and inhibits its apoptosis during inflammatory states and oxidative stress.[16][17] It also suppresses the pro-inflammatory mechanisms and augments anti-inflammatory mechanisms thus creating a possibility of its therapeutic use in various gastrointestinal inflammatory conditions including colitis, ischemia reperfusion injury and sepsis.[18][19] In fact, animal models of colitis, ischemia re-perfusion and sepsis related gut dysfunction have been shown to be benefited with therapeutic doses of ghrelin.[18][19] It has also been shown to have regenerative capacity and is beneficial in case of mucosal injury to the stomach.[20] Ghrelin also enhances the motility of gastrointestinal tract, as does motilin. Ghrelin also appears to promote gastrointestinal and pancreatic malignancy.[21][22][23]


Learning and memory

Animal models indicate that ghrelin may enter the hippocampus from the bloodstream, altering nerve-cell connections, and so enhancing learning and memory. It is suggested that learning may be best during the day and when the stomach is empty, since ghrelin levels are higher at these times. The team of the Yale School of Medicine also noted that a similar effect for human neural-physiology is quite plausible.[25] In rodents, X/A-like cells produce ghrelin.

Stress-induced depression

The hormone might help defend against symptoms of stress-induced depression and anxiety.[26] To test whether ghrelin could regulate depressive symptoms brought on by chronic stress, the researchers subjected mice to daily bouts of social stress, using a standard laboratory technique that induces stress by exposing normal mice to very aggressive bully mice. Such animals have been shown to be good models for studying depression in humans. The researchers stressed both wild-type mice and altered mice that were unable to respond to ghrelin. They found that, after experiencing stress, both types of mice had significantly elevated levels of ghrelin that persisted at least four weeks after their last defeat encounter. The altered mice, however, displayed significantly greater social avoidance than their wild-type counterparts, indicating an exacerbation of depression-like symptoms. They also ate less than the wild-type mice.[27]


Sleep-Duration

A study [28] appearing in the journal PLoS Medicine suggests that short sleep duration is associated with high levels of ghrelin and obesity; ghrelin appears to be a factor contributing to the short sleep duration and obesity. Scientists have uncovered an inverse relationship between the hours of sleep and blood plasma concentrations of ghrelin; as the hours of sleep increase, ghrelin concentrations were considerably lower, thereby potentially reducing appetite and avoiding potential obesity.



And here's a summary from Wikipedia of Grehlin and it's involvement in the workings of the biochemistry of the human body:


Ghrelin is a hormone produced mainly by P/D1 cells lining the fundus of the human stomach and epsilon cells of the pancreas that stimulates hunger.[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.

Ghrelin is also produced in the hypothalamic arcuate nucleus, where it stimulates the secretion of growth hormone from the anterior pituitary gland.[2] Receptors for ghrelin are expressed by neurons in the arcuate nucleus and the lateral hypothalamus. The ghrelin receptor is a G protein-coupled receptor, formerly known as the GHS receptor (growth hormone secretagogue receptor). Ghrelin receptor has also been identified as being expressed in vagal afferent cell bodies as well as the vagal afferent endings throughout the gastro-intestinal tract [3]

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.[4][5] Recently, ghrelin has been shown to activate the endothelial isoform of nitric oxide synthase in a pathway that depends on various kinases including Akt.[6]


...........................


then here are to titles of the research papers that were referenced in the Wikipedia page:



16 ^ Waseem T, Duxbury M, Ito H, Rocha F, Lautz D, Whang E, Ashley SW, Robinson MK (September 2004). "Ghrelin ameliorates TNF-a induced anti-proliferative and pro-apoptotic effects and promotes intestinal epithelial restitution". Journal of the American College of Surgeons 199 (3 Supplement): 16. doi:10.1016/j.jamcollsurg.2004.05.018.

17 ^ Waseem T, Duxbury M, Ito H, Ashley SW, Robinson MK (March 2008). "Exogenous ghrelin modulates release of pro-inflammatory and anti-inflammatory cytokines in LPS-stimulated macrophages through distinct signaling pathways". Surgery 143 (3): 33442. doi:10.1016/j.surg.2007.09.039. PMC 2278045. PMID 18291254.

..


that's pretty intriguing. But I haven't got any further. I'm wondering if anybody else's then researching Grehlin and it's involvement in the human body etc?

Thanks in advance.

Voner
 

taniaaust1

Senior Member
Messages
13,054
Location
Sth Australia
I spent a day researching Grehlin several months ago (came across it when researching something else and had been intreged) and thought that all the things its involved in was very interesting too.

Then a month ago it was talked about on one of the tv medical talk shows.... I think it was on Dr Oz's show. That was the first time I'd seen anything about it on tv and then I saw it mentioned again on tv only this week (forgotten what medical show but they mentioned newish operation done nowdays instead of stomach banding...and how they are finding it better to remove half a stomach which then lowers the levels of grehlin and hence helps the very obese).

It seems to be something which is currently attracting a lot of attention.
 
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