But according to our histochemical staining of HFpEF after CKD mice treated with AC-4-13, JAK2/STAT5 activation may induce myocardial hypertrophy and fibrosis by affecting calcium handling, endoplasmic reticulum stress, macrophage infiltration or cytokine surge (Fig. 6C-E). The gene discussed is JAK2; the disease is chronic kidney disease.