CCL4 and heart failure: First, as a protein drug, FGF2 is susceptible to chemical and biological instability under intravenous administration.[52] Second, systemic treatment with FGF2 may induce abnormal ectopic cell proliferation in tissues beyond the liver.[53] Third, systemic TZD treatment possibly causes side effects, such as bone rarefaction, and heart failure.[14b] In our CCL4‐induced liver injury model, it was unlikely that acute treatment with FGF2 or TZD caused serious adverse effects.