Statistical analysis

Unless otherwise specified, the significance differences between two treatment groups were determined by Student’s t-test, whereas the differences among multiple groups were determined by analysis of variance (ANOVA) using a randomized complete block design, followed by Tukey's honest significant difference test. To improve the validity of ANOVA, non-normal or heteroscedastic data were normalized using the corresponding basal level or transformed using variance stabilization transformation methods (e.g., arcsine transformation and Box-Cox power transformation) before ANOVA [53]. A significance level of 0.05 was applied during data analysis, and different significance levels have been indicated using different lowercase letters. In addition, the ANOVA data from the analysis of the viable live cells (annexin V-negative and PI-negative, gray bars) that were quantified by flow cytometry are provided in Supporting Information (S2 Table). We have indicated the 95% confidence intervals of the main and interaction effects.