Neurogastroenterology Studies

[mnsun]

A host of studies are available for limited time, not sure how long:
http://www.nature.com/nrgastro/collection/enteric

An app for phones here: http://gettag.mobi

IBD:Intestinal inflammation affected by density
of enteric neurons
http://www.nature.com/nrgastro/journal/v8/n10/pdf/nrgastro.2011.145.pdf
...concludes that “a preexisting hyperinnervation of the intestine, or segments of the intestine, may cause or predispose people to intestinal inflamation or may worsen inflammation once it occurs”.

 

[mnsun]

The study "IBS Distinct neuro–immune patterns defined in IBS subtypes" excerpt reads:
"Unexpectedly, supernatants from healthy individuals actually inhibited mechanosensitivity in the nerves; a mechanism that, according to the new data, occurs in an opioid-dependent manner and via β-endorphin secretion."

Maybe a correlation as to LDN's functioning? The calming of innervation may be key to halting the inflammation, though not targetting the source but stopping further damage?

 

[mnsun]

The following study sheds light on the whole "leaky gut" or "permeability" aspect of IBD as well as possible alternative therapies involving ENS modulation:"The digestive neuronal–glial–epithelial unit: a new actor in gut health and disease"
http://www.nature.com/nrgastro/journal/v10/n2/pdf/nrgastro.2012.221.pdf

The "Changes in IEB Permeability" section speak to Crohn's. The "Neuronal Control of IEB Functions" section is most interesting, as it speaks of the vagus nerve and various nutritional stimulation of ENS etc.

Other excerpts:
"In adult humans, increasing evidence suggests that altered IEB (intestinal epithelial barrier) functions have a central role in the aetiology and/or pathophysiology of a wide range of digestive and extradigestive diseases,38 such as type 1 diabetes mellitus, 40 rheumatic diseases41 and autism.42 Alterations of the IEB include increased paracellular and transcellular permeability, as well as reduced wound healing abilities leading to a ‘leaky gut’. Therefore, therapeutic approaches aimed at enhancing and/or restoring IEB functions might be of major interest for the prevention of various chronic diseases."

"Key points
■■ Altered functioning of the intestinal epithelial barrier (IEB) has a central role in the aetiology of a wide range of diseases; efficient IEB healing is essential to maintain IEB homeostasis
■■ An anatomical unit comprised of enteric neurons, enteric glial cells and
intestinal epithelial cells sets the basis for a functional digestive neuronal–
glial–epithelial unit
■■ Enteric neuromediators as well as gliomediators can differentially modulate
major IEB functions such as paracellular permeability, intestinal epithelial cell
proliferation and wound healing
■■ Changes in the phenotype of enteric neurons and glial cells occur in various diseases but the involvement of the enteric nervous system (active or
bystander) in these pathologies remains to be defined"

 

[Trysha]

Thank you for posting these interesting articles-------lots of food for thought here
Trysha

 

[mnsun]

This study focuses on nutritional modes of maintenance for IBS:
http://www.jacn.org/content/26/6/684S.full.pdf+html

Therein lies many general Neuro-Gut-Diet connections such as the many dynamic effects of beneficial probiotics which also pertain to Crohn's. The sections "Enteric Neuromuscular Dysfunction" and "Brain-Gut Axis Dysregulation" focus on the two way street between the gut and brain like what they term "hypothalamic-pituitary-adrenal (HPA) axis" and it's exagerated response due to TNF-a, etc..

 

[mnsun]

I thought I'd re-recommend an article posted in the Sept 2012, Monitor on Psychology magazine titled, "That Gut Feeling" by Dr. Siri Carpenter (pg. 50).

The article basically explains studies, mostly rats, that show it's a two-way street; the whole brain-gut dynamic. Meaning psychological upset can cause gut upset, just as much as gut upset can cause psychological upset via the "vagus" nerve which somehow connects gut microbiota populations(probiotics) to neurochemical responses resulting in depression/stress/anxiety.

The article detailed a few studies in which varying stress responses were shown to be reversed, or caused, by the introduction, or wiping-out, of specific probiotic strains. Of particular note were: Bifido Infantis, Lactobacillus Rhamnosus, Bifido Longum, and Lactobacillus Helveticus.

There werethree studies involving humans which showed promise. A study of college students observed diminished lactobacilli populations when comparing samples from the first few days of school to exam week. British Journal of Nutrition in 2011 found that "a 30-day course of probiotic bacteria (l. helveticus, b. longum) led to decreased anxiety and depression in health human volunteers." An as-of-yet unpublished neuroimaging study, examining the effects of probiotics on brain activity, revealed an "observable" effect on brain activities while they viewed either neutral or negative emotional stimuli.

I would definitely give such things due consideration. Whether or not you or your loved one has noticed digestive effects from various brands of probiotics should perhaps consider the mental states as well. That being said, different brands vary in quality and effectiveness greatly. Also, certain formulations may only be helpful for certain segments of the digestive tract--just my unqualified opinions.

 

[Jim (POPS)]

thanks for all the info.

 

[Gculk]

Yeah, makes sense.

Pain, even without injury, can cause inflammation. This is why capsaicin pepper spray can cause mucosal damage via inflammatory response, even though the only biochemical interaction is to cause pain neurons to fire.

I believe this also explains at least partially the incidence of mild inflammation in the context of IBS, IBS is considered a neuropathic pain, therefore in people with significant neuropathic pain, it would make sense that they would have neurologically induced inflammation.

This would be more of a me-too finding in my opinion. People that experience more pain would have more inflammation because inflammation causes pain causes inflammation. Sort of a vicious cycle.

Oh dear lord, my dog just sleepwalked. Was fast asleep, then bolted upright and sprinted down the hallway. Then came back with his tail between his legs.

Nathan

 

[mnsun]

A new article in the Mar/Apr '14 Psychology Today magazine titled, "The Psychobiotic Revolution", by Jordan Davidson fills in many blanks linking specific strains to reducing stress related cortisol (L. Helviticus, B. Longum), secreting GABA (generally labeled Lactobacillus and Bifidobacterium), altering serotonin levels (B. Infantis), increasing oxytocin (L. Reuteri), improving cannabinoid receptors in the spine to regulate pain (L. Acidophilus), attacking inflammation and regulating appetite (B. Infantis, L. Reuteri and others), reducing anxiety and depression (L. Rhamnosus), and suppressing proinflammatory cytokines (B. Infantis, L. Reuteri), among other benefits.

Interestingly, they note that the polyphenols in dark chocolate act as a prebiotic to specifically increase Bifido and Lacto bacterium populations.

A couple notable researchers to seek out may be Justin Sonnenburg, a Stanford microbiologist, and Ted Dinan, a psychiatrist at the University of Cork, Ireland.

Here's a a post I've typed previously:
I would just reiterate that another reason to supplement probiotics (L. Rhamnosus especially, among others) is to correct such emotional complications. The gut bacteria are increasingly being investigated for their role in behavior as well as the mind/gut connection of the vagus nerve and neurotransmitters (GABA).

Probiogenomics is shedding light on gut microbiota and behavioral/emotional states. http://www.pnas.org/content/early/2011/08/26/1102999108 --this link is specifically about L. Rhamnosus.

A poignant excerpt explains: "Importantly, L. rhamnosus (JB-1) reduced stress-induced corticosterone and anxiety- and depression-related behavior."

Here's further elaboration, though this was only a rat study (From Guts To Brains--Eating Probiotics Changes Behaviour in Mice) and it should be noted that L Rhamnosus studies have yet to be carried out on humans: http://blogs.discovermagazine.com/no...cience/?p=5235