Altered gut microbiome and serum metabolome profiles associated with essential tremor.

The genetic predisposition and environmental factors both trigger the complex neurological dyskinesia of essential tremor (ET). Gut dysbiosis may facilitate the occurrence and development of neurological diseases. Therefore, it is worth exploring the inner connections between gut microbiota and ET. First, the gut microbiota of 19 ET patients and 21 healthy controls (HCs) were analysed with metagenomics approach. Second, the potential linkages between gut microbiome and serum metabolome profiles were explored by integrative analysis. The gut microbiota disorders were present in ET patients. The LEfSe method showed a significant decrease in Bacteroides. The functional analysis revealed that there were differences in gut microbial apoptosis, retinol metabolism, and steroid hormone biosynthesis pathways. The levels of various lipids and lipid-like molecules alter in serum of ET patients, which correlated with altered gut microbial abundance, indicating the alterations in lipid metabolism involved in apoptosis pathway in ET. All of these data point to the gut dysbiosis in ET, and some changed gut microbial species were linked to abnormalities in blood lipid metabolism, which open up new avenues for investigation into the pathophysiology of ET.