Hormesis in Caenorhabditis elegans exposed to pollutants

Hormesis is reported for various environmental pollutants and is believed to be a highly common phenomenon. Caenorhabditis elegans nematodes have advantages of easy handling, strong fecundity, and fully deciphered genome, and therefore are widely employed in toxicity studies of various pollutants. However, hormesis on this nematode is still in the infancy. This mini review summarized hormesis (especially the stimulatory effects) on C. elegans by pollutants and also dietary components or chemicals. The progresses were stated with two categories, one as apical hormesis with indicators of growth, lifespan, reproduction, and behavior, and the other one as biochemical hormesis with those of antioxidant responses, lipid metabolism, and neurotransmitters. Hormesis studies with omics analysis and those over generations were also included for the explanation on hormesis mechanisms. The review also pointed out considerations for the standardization of methodology, the trade–off relationships among indicators and over generations, and the exploration of the underlying mechanisms in future studies.