Gliquidone alleviates DSS-induced ulcerative colitis in rats by targeting carnitine palmitoyltransferase 1A

Ulcerative colitis (UC) is an idiopathic, chronic inflammatory disorder with an increasing incidence worldwide. Due to the complex and unclear therapeutic targets, unmet UC therapeutic drugs still exist. Recently, acylcarnitine metabolism disorder has been linked to intestinal inflammation, but its role in UC remains elusive. According to our preliminary non-targeted metabolomics data, acylcarnitines (ACs) was screened as the disturbed metabolites in the different intestinal inflammation-related diseases. Here we quantified 26 ACs within liquid chromatography-tandem mass spectrometry (LC-MS/MS) in the dextran sulfate sodium (DSS)-induced UC rat model, and found that long-chain acylcarnitines (LCACs) were increased to varying degrees. As the key metabolites of fatty acid β-oxidation (FAO), the upstream metabolites long-chain fatty acids (LCFAs) and the related metabolic enzymes were further characterized, the results showed that the rate-limiting enzyme carnitine palmitoyltransferase 1A (CPT1A)-mediated LCFAs-LCACs metabolic axis was activated sharply. Next in vitro experiments exhibited that CPT1A was significantly upregulated in both inflammatory macrophages and colonic epithelial cells, and inhibition or knockdown of CPT1A could reduce the inflammation level remarkably. Thus, we screened the pharmacologic inhibitors of CPT1A from US Food and Drug Administration (FDA) approved drugs, within molecular docking, Western blot and cell membrane chromatography (CMC) technology, gliquidone was found to inhibit CPT1A in a dose-dependent manner and exert anti-inflammatory effects in vitro. Animal experiments also showed that gliquidone alleviated DSS-induced UC significantly. In summary, our study presents that within metabolomics analysis, inhibiting CPT1A is focused to be a potential therapeutic strategy against UC, and gliquidone represents an alternative treatment.