Glucagon-like peptide-1 attenuates cardiac hypertrophy via the AngII/AT1R/ACE2 and AMPK/mTOR/p70S6K pathways

Glucagon-like peptide-1 (GLP-1), a novel type of glucose-lowering agent, has been reported to exert cardioprotective effects. However, the cardioprotective mechanism of GLP-1 on spontaneous hypertension-induced cardiac hypertrophy has not been fully elucidated. In this study, we revealed that liraglutide or alogliptin treatment ameliorated spontaneous hypertension-induced cardiac hypertrophy, as evidenced by decreased levels of cardiac hypertrophic markers (atrial natriuretic peptide, brain natriuretic peptide, and β-myosin heavy chain), as well as systolic blood pressure, diastolic blood pressure, mean arterial pressure, and histological changes. Both drugs significantly reduced the levels of angiotensin II (AngII) and AngII type 1 receptor (AT1R) and upregulated the levels of AngII type 2 receptor (AT2R) and angiotensin-converting enzyme 2 (ACE2), as indicated by a reduced AT1R/AT2R ratio. Simultaneously, treatment with liraglutide or alogliptin significantly increased GLP-1 receptor expression and adenosine monophosphate-activated protein kinase (AMPK) phosphorylation and downregulated the phosphorylation of mammalian target of rapamycin (mTOR), p70 ribosomal S6 protein kinase, and eukaryotic translation initiation factor 4E binding protein 1 in spontaneous hypertension rats. Furthermore, our data demonstrated that the AMPK inhibitor compound C or mTOR activator MHY1485 inhibited the anti-hypertrophic effect of GLP-1. In summary, our study suggests that liraglutide or alogliptin protects the heart against cardiac hypertrophy by regulating the expression of AngII/AT1R/ACE2 and activating the AMPK/mTOR pathway, and GLP-1 agonist can be used in the treatment of patients with cardiac hypertrophy.