In HepG2 cells, GN efficiently decreased JMJD2B expression and subsequently reduced the expression of PPARγ2 and its steatotic target genes, which suggests the possible contribution of the GN-mediated inhibition of JMJD2B–PPARγ2 signaling to the progression of HFD-induced hepatic steatosis. The gene discussed is PPARG; the disease is fatty liver disease.