Abstract:

The effects of chlorogenic acid (CGA) on the longevity and antioxidant activity of the entomopathogenic nematodes (EPNs) Steinernema kraussei were investigated through treating S. kraussei with different concentrations of chlorogenic acid (0, 50, 100, 500, 1000 µmol/L) and then recording S. kraussei longevity, antioxidant activity, lipofuscin levels, and related genes mRNA expression levels, with the aim to explore the potential mechanisms of action of chlorogenic acid. The results showed that the maximum longevity of S. kraussei was increased by 36.36% in the treatment with100 µmol/L chlorogenic acid in comparison to the control, significantly inhibited the accumulation of lipofuscin related to aging, but increased SOD and CAT enzyme activities by 1.97 and 2.47 times, respectively. Moreover, qRT-PCR results showed that daf-16 and gst-4 genes transcription levels was increased by 1.78 and 3.51, respectively, in the nematodes fed with 100 µmol/L CGA compared with the control. However, the daf-2 gene transcription level showed a downward trend and decreased by 0.13. This study demonstrates that chlorogenic acid enhances the antioxidant activity and prolong the longevity of entomopathogenic nematodes S. kraussei by regulating the insulin/IGF-1 signaling pathway.

Key words:

chlorogenic acid, entomopathogenic nematodes, lifespan; antioxidant, insulin/IGF-1 signaling pathway