Emerging investigator series: examination of the gastrointestinal lipidome of largemouth bass exposed to dietary single-walled carbon nanotubes†
Carbon nanomaterials are emerging contaminants released into the environment primarily through anthropogenic processes, where they primarily partition into soils and sediments. Aquatic animals that inhabit, forage, or choose prey in the benthic zone are vulnerable to dietary exposure to sediment-associated carbon nanomaterials. Since carbon nanomaterials are hydrophobic, dietary exposure may alter the availability, metabolism, storage, and transport of lipids in the intestinal lumen or at the epithelial barrier, affecting downstream biological processes. To assess the effect of single-walled carbon nanotubes (SWCNTs) on the gastrointestinal lipidome of aquatic species, a feeding experiment with adult largemouth bass (Micropterus salmoides) was conducted. After 8 weeks of exposure to SWCNTs via the diet, the intestinal abundance of ceramides and several classes of lyso- and phospholipids was significantly altered. Additionally, functional profiling with MetaboAnalyst revealed changes in pathways related to fatty acid biosynthesis in exposed fish. These results suggest that though SWCNTs do not pass through the gastrointestinal epithelium, they may alter gut homeostasis through interactions with intestinal lipids.