USP25 Ameliorates Pathological Cardiac Hypertrophy by Stabilizing SERCA2a in Cardiomyocytes

Abstract

BACKGROUND: Pathological cardiac hypertrophy can lead to heart failure and is one of the leading causes of death globally. Understanding the molecular mechanism of pathological cardiac hypertrophy will contribute to the treatment of heart failure. DUBs (deubiquitinating enzymes) are essential to cardiac pathophysiology by precisely controlling protein function, localization, and degradation. This study set out to investigate the role and molecular mechanism of a DUB, USP25 (ubiquitin-specific peptidase 25), in pathological cardiac hypertrophy. METHODS: The role of USP25 in myocardial hypertrophy was evaluated in murine cardiomyocytes in response to Ang II (angiotensin II) and transverse aortic constriction stimulation and in hypertrophic myocardium tissues of heart failure patients. Liquid chromotography with mass spectrometry/mass spectrometry analysis combined with Co-IP was used to identify SERCA2a (sarcoplasmic/endoplasmic reticulum Ca2+-ATPase 2A), an antihypertrophy protein, as an interacting protein of USP25. To clarify the molecular mechanism of USP25 in the regulation of SERCA2a, we constructed a series of mutant plasmids of USP25. In addition, we overexpressed USP25 and SERCA2a in the heart with adenoassociated virus serotype 9 vectors to validate the biological function of USP25 and SERCA2a interaction. RESULTS: We revealed increased protein level of USP25 in murine cardiomyocytes subject to Ang II and transverse aortic constriction stimulation and in hypertrophic myocardium tissues of patients with heart failure. USP25 deficiency aggravated cardiac hypertrophy and cardiac dysfunction under Ang II and transverse aortic constriction treatment. Mechanistically, USP25 bound to SERCA2a directly via its USP (ubiquitin-specific protease) domain and cysteine at position 178 of USP25 exerts deubiquitination to maintain the stability of the SERCA2a protein by removing the K48 ubiquitin chain and preventing proteasomal pathway degradation, thereby maintaining calcium handling in cardiomyocytes. Moreover, restoration of USP25 expression via adenoassociated virus serotype 9 vectors in USP25 −/− mice attenuated Ang II-induced cardiac hypertrophy and cardiac dysfunction, whereas myocardial overexpression of SERCA2a could mimic the effect of USP25. CONCLUSIONS: We confirmed that USP25 inhibited cardiac hypertrophy by deubiquitinating and stabilizing SERCA2a.

Post‐translational modifications in diabetic cardiomyopathy

“…Atrogin‐1 promoted ubiquitination of calcineurin, thereby inhibiting cardiomyocyte hypertrophy 116 (Figure 5). According to Ye et al., the deubiquitinating enzyme ubiquitin‐specific peptidase 25 (USP25) can combined with SERCA2a and prevent proteasomal pathway from degrading it 117 . This process not only maintained calcium homeostasis in cardiomyocytes but also contributed to the inhibition of cardiac hypertrophy.…”

Secondary Sites of the C‐type Lectin‐Like Fold

“…[110,[223][224][225][226][227][228][229] Although the exact binding mode of most protein ligands for dectin-1 is still an open question, the interaction of human dectin-1 with CLEC-2 has been mapped to a distinct interactions motif in the stalk of dectin-1 and binding sites of annexins and angiotensin II appears to be different from the binding site of βglucan. [110,224,226] Dectin-1 illustrates how a binding site distinct from canonical Ca 2 + -dependent carbohydrate recognition site mediates glycan binding and becomes the primary binding site for the role of dectin-1 as a pattern recognition receptor. Moreover, the existence of multiple protein ligands with potentially more distinct binding sites underlines the functional variability of the CTLD fold.…”

The role of deubiquitinases in cardiac disease

“…Research showed that USP25, as a protective protein of the heart, played an anti-hypertrophic role in pathological myocardial hypertrophy (Ref. 55 ). Ye et al found that knocking out USP25 in mice exacerbated myocardial hypertrophy induced by angiotensin II and TAC.…”

“…USP25 stabilized intracellular calcium homeostasis and alleviated myocardial hypertrophy by removing the K48-linked ubiquitin chains of SERCA2a protein (Ref. 55 ). Coincidentally, the team also found that JOSD2 maintained myocardial calcium homeostasis by upregulating SERCA2a, thereby attenuating cardiac hypertrophy (Ref.…”