The grayscale values of protein bands showed that the phosphorylation ratios of PI3K, Akt, and Erk were significantly decreased in the GPS infection group and significantly increased in the quercetin groups, with 2.5 μg/mL quercetin exhibiting the best effect (p < 0.001 for 2.5 μg/mL quercetin, Figure 11C). Here, AKT1 is linked to infection.