Lewy bodies in the gut's nerve plexuses

The research record

This is the project's file for this landmark, as written and checked. Sources are listed at the end; anything not yet confirmed is marked "Not yet verified".

Who

Koichi Wakabayashi, Hitoshi Takahashi, Shigeki Takeda, Eisaku Ohama and Fusahiro Ikuta. Department of Pathology, Niigata University, Japan (first author's affiliation in PubMed).

What happened

The team examined the enteric nervous system (the web of nerve cells that runs the gut) in seven people who had died with Parkinson's. They looked at two networks: Auerbach's plexus (between the gut's muscle layers) and Meissner's plexus (in the layer under the lining).

• Inclusions that looked identical to Lewy bodies under the light and electron microscope were present in both plexuses in all seven patients.
• They were most frequent in Auerbach's plexus of the lower oesophagus.
• Lewy bodies also turned up in 8 of 24 age-matched people without Parkinson's, but in much smaller numbers.

The authors concluded that the gut plexuses are also involved in Parkinson's. The paper appeared in Acta Neuropathologica 76:217–221, 1988. It predates the discovery that synuclein is the main protein in Lewy bodies (landmark 5), so the staining was by shape, not by synuclein.

Why it moved us toward a cure

It extended the Lewy body, first described in the brain (landmark 21), to a nerve network outside the brain. That gave the gut-origin idea an anatomical footing. Braak's later staging (landmark 6) starts in the lower brainstem and suggested a trigger might enter through the gut or nose, and registry work on vagus-nerve cutting and the appendix (landmark 83) tried to test it in people. If the disease starts at the gut surface, there is a place to intervene early.

Outcome

Advanced. Gut Lewy pathology is now widely accepted. The sample was tiny, and the small number in some controls foreshadowed the later specificity problem with gut biopsies (landmark 261). The finding alone does not show that the disease starts in the gut.

Sources

• Wakabayashi et al., "Parkinson's disease: the presence of Lewy bodies in Auerbach's and Meissner's plexuses", Acta Neuropathol 1988, DOI 10.1007/BF00687767, PMID 2850698, 76:217–221 (abstract via Europe PMC and PubMed)
• Not yet verified: whether the cases were all brain-confirmed; the exact control group (abstract says only 24 age-matched non-parkinsonian patients); any earlier report of gut Lewy bodies, so "first" is not claimed; funding (not stated in the abstract).