MAPK8 and hydrops fetalis: In contrast to levels in the mice in the ISO group and the ISO + PBS group, exogenous supplementation with the SFRP5 recombinant protein upregulated the expression of SFRP5 in myocardial tissues, which inhibited the WNT5A/JNK signaling pathway and ultimately alleviated ISO-induced HF in mice (Figure 6).