The vagus nerve and the inflammatory reflex—linking immunity and metabolism
One page on PainSci cites Pavlov 2012: Chronic, Subtle, Systemic Inflammation
PainSci commentary on Pavlov 2012: ?This page is one of thousands in the PainScience.com bibliography. It is not a general article: it is focused on a single scientific paper, and it may provide only just enough context for the summary to make sense. Links to other papers and more general information are provided wherever possible.
The vagus nerve is the “relaxation” nerve. Relaxation involves several physiological changes stimulated by vagus nerve activity. If you could artificially stimulate your vagus nerve, it would relax you — and perhaps more. The vagus nerve also regulates immune system activity by detecting and responding to signs of inflammation — the “inflammatory reflex.” Immune regulation is insanely complex, but the inflammatory reflex is a major component of that system.
The inflammatory reflex may be impaired in people with excessive inflammation. This paper discusses the role of the inflammatory reflex in obesity specifically, but frequently mentions the potential relevance to other conditions associated with chronic inflammation. The paper is all about “the intriguing possibility that dysregulation of vagus nerve-mediated signalling might contribute to the pathogenesis of obesity and its related comorbidities.”
There are dizzyingly complex passages about “novel therapeutic approaches” that might achieve “cholinergic suppression of inflammation” either by inspiring the vagus nerve to do it, or by doing it directly by other means. Mostly it’s about exotic drugs, and there’s a passage about implanted vagus nerve stimulators (none of which is practical or accessible). There’s some discussion of the effects of nutrition (much more accessible).
What it does not discuss is how normalization of the inflammatory reflex might be achieved by simple relaxation — but that is certainly implied, and seems well worth exploring.
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
The vagus nerve has an important role in regulation of metabolic homeostasis, and efferent vagus nerve-mediated cholinergic signalling controls immune function and proinflammatory responses via the inflammatory reflex. Dysregulation of metabolism and immune function in obesity are associated with chronic inflammation, a critical step in the pathogenesis of insulin resistance and type 2 diabetes mellitus. Cholinergic mechanisms within the inflammatory reflex have, in the past 2 years, been implicated in attenuating obesity-related inflammation and metabolic complications. This knowledge has led to the exploration of novel therapeutic approaches in the treatment of obesity-related disorders.
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
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