Galaninergic System Dysregulation in Long-COVID: Neural injury Associations

Background: Long-COVID disease, is a term that describes the persistent SARS-CoV-2 symptoms, is challenging to diagnose due to its complexity and incompleteness of pathogenesis. Although numerous factors were explored with this condition, the Galanin (GAL) and its receptor 1 (GalR-1) were not extensively studied in this context. Galanin system engaged in the pathophysiology of multiple chronic aging-related diseases, including alcoholism, inflammatory conditions of bowel and skin, and chronic pain. The presented study aimed to evaluate the relationship between tested Galanin system parameters in Long-COVID patients. Methods: The amount of GAL and GALR-1 were measured using the ELISA technique in a group of (90) Long-COVID patients and (60) individuals who had healing and were no longer experiencing symptoms of Long-COVID. Results: The study reported that Galanin, GalR-1, and Gal/GalR-1 ratio were significantly increased in Long-COVID patients. The study reported statistically higher Galanin levels (p<0.001), higher GALR1 levels (p = 0.007) and higher Gal/GalR1 ratios (p=0.019) in individuals diagnosed with Long-COVID patients and non-patients. According to the ROC analysis, Galanin showed the highest sensitivity (71.7%) followed by GALR1 (60.0%) to discriminate patients from non-patients. Conclusion: The findings suggest a direct relationship between Galanin and GALR1 with Long-COVID disease. However, further studies are needed to clarify the precise role of plasma Galanin(GAL) and its receptors(GalR-1) in Long-COVID pathology.