Thesis
 

By Dr. Purushottam Sah
Corresponding Author Dr. Purushottam Sah
Gynecology. Nightingale Hospital, - India
Submitting Author Dr. Purushottam Sah
DISEASE MECHANISMS

Diabetes, Vagus, Mechanism, Treatment, Anticholinergics, Hyoscine

Sah P. Hyperactive Vagus Syndrome Causing Hyperglycemia!. WebmedCentral DISEASE MECHANISMS 2011;2(8):WMC002106
doi: 10.9754/journal.wmc.2011.002106
No
Click here
Submitted on: 21 Aug 2011 03:01:56 PM GMT
Published on: 22 Aug 2011 04:23:27 PM GMT

Abstract


Background: This is a hypothesis based on an observation made by the author when he was a rotating intern in the department of internal medicine. It was observed by the author that some patients admitted in the ward with peptic ulcer disease had their blood sugar levels above normal and their blood sugar levels came down to be within normal limits with anticholinergics containing hyoscine. The author explains it through the hypothesis of Hyperactive Vagus Syndrome.
Conclusion: In some people vagus nerve is hyperactive and causes peptic ulcer disease together with hyperglycemia. This hyperglycemia can be corrected with the use of anticholinergics drugs. This aspect needs further experimental exploration.


Hypothesis


Background: This hypothesis is based on an observation made by the author when he was a rotating intern in the department of internal medicine at Bankura Sammilani Medical College, Bankura, India. It dates back to November – December 1981. It was observed by the author that some patients admitted in the ward with peptic ulcer disease had their blood sugar levels above normal. Furthermore their blood sugar levels came down to be within normal limits with anticholinergics containing hyoscine. This was the usual treatment done at that time. The author observed it as a student intern. He had no role in the therapeutic intervention. The observation was not in accordance with the earlier findings as follows:
1. Peptic ulcer was found only rarely in diabetics [1].
2. Achlorhydria was more commonly present in diabetics than would be expected [2].
It’s obvious that peptic ulcer disease and hyperglycemia should not normally coexist. But the author’s observation was contrary so he explained it through the hypothesis of Hyperactive Vagus
Syndrome: ‘In some people vagus nerve is hyperactive and causes peptic ulcer disease together with hyperglycemia. This hyperglycemia can be corrected with the use of anticholinergics drugs’.
Explanation: The blood glucose level is maintained by a dynamic equilibrium between it and insulin. Insulin hypoglycemia causes vagus stimulation and gastric secretion [3]. By ill understood mechanism vagus stimulation also causes hypoglycemia [4].
In diabetics the effect of insulin is negligible and the higher glucose depresses the vagus [1] which then further increases glucose- a vicious cycle. This depressed vagus also decreases the gastric secretion conforming to the observations of Hosking et.al [1] and Rabinowitch [2].
In case of hyperactive vagus tending to cause hypoglycemia, this equilibrium is disturbed but as the effect of insulin is not absent (contrary to diabetics) glucose is maintained by interplay of three factors, namely glucose, insulin and vagus (Illustration.1). As the hyperactive vagus tends to cause hypoglycemia, this equilibrium is adjusted so that the glucose is maintained at higher levels. Thus glucose is maintained at higher than normal level so that the hyperactive vagus if ever lowers the glucose there will be no chances of hypoglycemia taking place.
Discussion: Not all the patients having peptic ulcer disease have higher blood sugar levels, because the disease has several etiologies. Common exogenous causes of peptic ulcer are Helicobacter pylori infection and administration of ulcer causing drugs. The endogenous cause of hyperactive vagus may be emotional or may be due to excessive stimulation of autonomic ganglion caused by nicotine (partly exogenous). The men who were observed were also smokers and their diastolic blood pressures were mildly elevated. This hypothesis was not further developed by the author because he took another specialty after graduation. But he conjectures if anticholinergics be a part of therapy for diabetes as glucose and vagus are involved in a vicious cycle! This aspect needs further experimental exploration. Though it may appear bit old, yet old views sometimes come out with new evidence if re-explored.


References


1. Hosking DJ, Moody F, Stewart IM, Atkinson M. Vagal impairment of gastric secretion in diabetic autonomic neuropathy. Br Med J 1975; 2:588-590.
2. Rabinowitch IM. Achlorhydria and its clinical significance in diabetes mellitus.  Am J Dig Dis 1949; 16: 322-332.
3. Kneller AW, Nasset ES. Relationship of insulin hypoglycemia to intestinal secretion. Am J Physiol 1949; 159: 89-94.
4. Best CH and Taylor NB eds. The Physiological Basis of Medical Practice . The Williams & Wilkins Company, Baltimore, Maryland, 1966:1104.

Further evidence in support of this hypothesis.


I have mentioned in this hypothesis ‘As the hyperactive Vagus tends to cause hypoglycemia, the bodily equilibrium is adjusted so that the glucose is maintained at higher levels’. I have also observed that the elevated blood sugar levels of the patients came down with the anticholinergic Hyoscine.
This hypothesis is three decades old but newer evidences, involving GIP and GLP-1, support it. Gastric inhibitory polypeptide (GIP) along with glucagon-like peptide-1 (GLP-1) belongs to a class of hormones referred to as Incretins that lower blood sugar levels.
The findings of a study (1) demonstrating a stimulatory role for the Vagus nerve in secretion of GLP-1  and another report (2) mentioning cholinergic fibres having positive effects on  Incretin  secretion, supports our hypothesis that ‘hyperactive Vagus tends to cause hypoglycemia’.
In another study (3) the authors conclude: suppression of Vagally mediated GLP-1, GIP secretion alone by Hyoscine cannot explain the blood glucose profile, which would then be expected to be higher, rather than lower and overall blood glucose concentrations were lower with Hyoscine infusion. This explains the ‘paradox’ of our ‘hypothesis’ and also supports the observation that elevated blood sugar levels of patients came down with drugs containing Hyoscine .

References


1. Role of the Vagus Nerve in Mediating Proximal Nutrient-Induced Glucagon-Like Peptide-1 Secretion. A.S.Rocca,P.L.Brubaker. Endocrinology 1999 140: 1687-1694; doi:10.1210/en.140.4.1687.
2. What do we know about the secretion and degradation of incretin hormones? Deacon, CF. Regulatory Peptides, Volume: 128 Issue: 2   Pages: 117-124   DOI:10.1016/j.regpep.2004.06.007  
3. Concurrent duodenal manometric and impedance recording to evaluate the effects of hyoscine on motility and flow events, glucose absorption, and incretin release.
Chaikomin R, Wu K.L., Doran S., Jones K.L., Smout A.J., Renooij W.,  Holloway R.H., Meyer J.H., Horowitz M., Rayner C.K. Am J Physiol Gastrointest Liver Physiol, 2007 Apr;292(4):G1099-104. Epub 2007 Jan 4.

Source(s) of Funding


none

Competing Interests


none

Disclaimer


This article has been downloaded from WebmedCentral. With our unique author driven post publication peer review, contents posted on this web portal do not undergo any prepublication peer or editorial review. It is completely the responsibility of the authors to ensure not only scientific and ethical standards of the manuscript but also its grammatical accuracy. Authors must ensure that they obtain all the necessary permissions before submitting any information that requires obtaining a consent or approval from a third party. Authors should also ensure not to submit any information which they do not have the copyright of or of which they have transferred the copyrights to a third party.
Contents on WebmedCentral are purely for biomedical researchers and scientists. They are not meant to cater to the needs of an individual patient. The web portal or any content(s) therein is neither designed to support, nor replace, the relationship that exists between a patient/site visitor and his/her physician. Your use of the WebmedCentral site and its contents is entirely at your own risk. We do not take any responsibility for any harm that you may suffer or inflict on a third person by following the contents of this website.

Reviews
2 reviews posted so far

Thanks to Prof. Leticia Santos for reviewing my article. I agree that the data is not enough to show statistical significance making the report weak. That’s why I have presented it as a hypothesis... View more
Responded by Dr. Purushottam Sah on 11 Jan 2011 04:46:30 AM GMT

Thanks to Dr. Osama Ahmed for reviewing my article. He has mentioned that he can suggest brief additions or amendments or an introductory statement that will increase the value of this paper for an in... View more
Responded by Dr. Purushottam Sah on 12 Dec 2010 10:02:52 AM GMT

Comments
1 comment posted so far

Can vagotomy cause remission of hyperglycemia ! Posted by Dr. Purushottam Sah on 17 May 2013 05:59:09 AM GMT

Please use this functionality to flag objectionable, inappropriate, inaccurate, and offensive content to WebmedCentral Team and the authors.

 

Author Comments
0 comments posted so far

 

What is article Popularity?

Article popularity is calculated by considering the scores: age of the article
Popularity = (P - 1) / (T + 2)^1.5
Where
P : points is the sum of individual scores, which includes article Views, Downloads, Reviews, Comments and their weightage

Scores   Weightage
Views Points X 1
Download Points X 2
Comment Points X 5
Review Points X 10
Points= sum(Views Points + Download Points + Comment Points + Review Points)
T : time since submission in hours.
P is subtracted by 1 to negate submitter's vote.
Age factor is (time since submission in hours plus two) to the power of 1.5.factor.

How Article Quality Works?

For each article Authors/Readers, Reviewers and WMC Editors can review/rate the articles. These ratings are used to determine Feedback Scores.

In most cases, article receive ratings in the range of 0 to 10. We calculate average of all the ratings and consider it as article quality.

Quality=Average(Authors/Readers Ratings + Reviewers Ratings + WMC Editor Ratings)