Figure 2. Icariside II promotes stress resistance and slows age related decline in movement in C. elegans.

A. Icariside II pre-exposure elevated the N2 adults' survival significantly under thermostress. Animals were pre-treated with the DMSO control (1%) or 20 µM icariside II starting from day 1 adulthood for four days. Shown is the combination of two replicates. Mean survival time, DMSO control, 9.7 hrs; icariside II, 11.3 hrs. Animals tested: 87 (DMSO control); 95 (icariside II). P = 0.0151 (Log-rank (Mantel-Cox) Test). B. Pre-treatment with icariside II increased oxidative stress resistance significantly. Day 1 wild type adults were treated with DMSO control or 20 µM icariside II for 4 days and then soaked in different concentrations of H₂O₂ (10, 15, 20 mM) for 2 hrs. Survival percentages were scored after a 16 hours recovery window in regular NGM. Shown are average survival percentages in 3 experiments with 30–50 animals/experiment. Total number of animals tested: 102 (DMSO Control), 113 (icariside II 20 µM); error bars indicate SEM among three independent experiments; t-test, ^* P<0.05. C. Treatment with icariside II extends swimming healthspan in advanced age; Average swimming bends per 30 seconds in 15 animals were scored in two independent trials; error bars indicate SEM among individual animals scored; t-test, ^** P<0.01. D. Icariside II treatment slows the age-related deterioration of C. elegans body wall muscle. Age-related deterioration of C. elegans body wall muscle is indicated by GFP fluorescence decline of a p_myo-3NLS::GFP fusion in the strain PD4251. Representative images of whole-animals treated with DMSO control and icariside II are presented at the ages indicated (25°C). E. Quantitation of the number of fluorescent nuclei in PD4251 treated with DMSO or icariside II. 15 animals of each strain were scored in two independent trials. Error bars indicate SEM among individual animals scored; t-test, ^*** P<0.001.