Vagal cholinergic denervation of the gastric mucosa in Long-COVID-19: In vivo evidence of structural autonomic dysfunction.
Patients with Long-COVID-19 show reduced cholinergic innervation in the gastric mucosa, which may contribute to dysautonomia.
Where it sits
this study against the rest of the vip (vasoactive intestinal polypeptide) corpusSummary and findings
This study measured gastric mucosal cholinergic innervation in 12 patients with Long-COVID-19 compared to 8 controls. Significant reductions in nerve fiber density were observed in both the fundus and antrum of Long-COVID-19 patients. The findings suggest structural autonomic dysfunction associated with Long-COVID-19.
Abstract
Objectives Dysautonomia has been increasingly recognized as a key feature of Long-COVID-19, potentially contributing to persistent gastrointestinal and systemic symptoms. Reduced vagal activity observed in these patients may reflect structural damage to autonomic fibers. We hypothesized that dysautonomic manifestations in Long-COVID-19 are associated with impaired cholinergic innervation of the gastric mucosa. Methods We conducted a case-control study including 12 patients with Long-COVID-19 and 8 control subjects undergoing routine gastroscopy. Gastric mucosal biopsies were analyzed using immunohistochemistry with the pan-neuronal marker protein gene product 9.5 (PGP 9.5) and vasoactive intestinal peptide (VIP) as a marker of cholinergic fibers. Nerve fiber density was quantified in both fundus and antrum samples. Results Compared with controls, Long-COVID-19 patients exhibited a significant reduction in mucosal innervation density: 2.1 vs 3.9 nm/µm³ (P < 0.01) in the fundus and 1.9 vs 3.9 nm/µm³ (P < 0.05) in the antrum. The reduction in cholinergic innervation was more pronounced in the fundus (P < 0.01) and also evident in the antrum (P = 0.01). Gastric nerve density correlated with HRV parameters (LF/HF ratio: R = 0.50, P < 0.05) and NT-proBNP levels (R = 0.52, P < 0.01). Conclusions Patients with Long-COVID-19 exhibit reduced gastric mucosal cholinergic innervation. This structural autonomic impairment may represent an anatomical substrate underlying dysautonomia in Long-COVID-19.
Background
Not reported in abstract.
Methods
Not reported in abstract.
Results
Not reported in abstract.
Interpretation
Not reported in abstract.
Limitations
Not reported in abstract.