NPPA and cardiac hypertrophy: Accordingly, SP1 activity was reduced in murine cardiomyocytes exposed to Na2S. Finally, co-treatment of murine cardiomyocytes with Hcy (100 μM) and Na2S (30 μM) for 24 h significantly mitigated cardiac hypertrophy induced by HHcy, in terms of increased cell area and expression of molecular markers of cardiac remodeling, such as atrial-natriuretic peptide (ANP) and β-myosin heavy chain (β-MHC).