Catalpol Modulates Lifespan via DAF-16/FOXO and SKN-1/Nrf2 Activation in Caenorhabditis elegans

Figure 4

Effects of catalpol on the antioxidant enzyme activity and intracellular ROS levels of wild-type N2 nematodes. (a) The enzymatic reaction of xanthine with xanthine oxidase was used to generate • and the SOD activity was estimated spectrophotometrically through formazan formation by NBT reduction. SOD activity was expressed as a percentage of the scavenged amount per control. (b) Catalase activity was calculated from the concentration of residual H₂O₂, as determined by a spectrophotometric method. Catalase activity was expressed in U/mg protein. (c) Fluorescence intensity of SOD-3::GFP expression in control and catalpol-treated CF1553 worms and their images. Mean GFP intensity was represented as mean ± S.E.M. of values from 19–24 animals per each experiment (). (d) Intracellular ROS accumulation was quantified spectrometrically at excitation 485 nm and emission 535 nm. Plates were read every 30 min for 2 h. Data are expressed as the mean ± S.E.M. of three independent experiments (). Differences compared to the control were considered significant at and by one-way ANOVA.

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