MAPK8 and osteoarthritis, knee: According to studies, AST reduced the protein phosphorylation of JNK and p38 MAPK, which in turn inhibited the JNK/p38 MAPK pathway, by reducing the ratio of p-JNK/JNK and p-p38 MAPK/p38 MAPK in the cartilage tissue of knee osteoarthritis (KOA) mice [99].