In STZ-induced DN rats, STZ injection promoted TGF-β1 and Smad3 expression but reduced SIRT3 expression, whereas these changes were reversed by knockdown of LSD1, indicating that knockdown of LSD1 deactivated TGF-β1/Smad3 pathway in vivo (Fig. 5A). The gene discussed is KDM1A; the disease is liver dysplastic nodule.