NR4A1 and diabetes mellitus: The RNA-Seq results showed that mRNA levels of Nur77 was downregulated by ~20-fold (Fig. 5a), which plays a critical role in causing mitochondrial dysfunction in diabetes.19–21 Further real-time PCR and western blot confirmed the downregulation of cardiac Nur77 in db/db mice treated with FGF1ΔHBS (Fig. 5b, c).