BECN1 and myocarditis: The quantitative results in vivo showed that hucMSCs‐exosomes in H‐EXO (50 μg) could significantly increase the levels of pAMPK, autophagy proteins LC3‐II/I and Beclin‐1 but decrease the level of pmTOR and promote the degradation of autophagy flux marker P62, without affecting AMPK and mTOR levels in the heart tissues of CVB3‐induced myocarditis mice (Figure 5B).