1
|
Rouhi L, Cheedipudi SM, Cathcart B, Gurha P, Marian AJ. Cytosolic DNA sensing protein pathway is activated in human hearts with dilated cardiomyopathy. THE JOURNAL OF CARDIOVASCULAR AGING 2023; 3:32. [PMID: 37577061 PMCID: PMC10421632 DOI: 10.20517/jca.2023.20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Introduction The genome is constantly exposed to numerous stressors, which induce DNA lesions, including double-stranded DNA breaks (DSBs). DSBs are the most dangerous, as they induce genomic instability. In response to DNA damage, the cell activates nuclear DNA damage response (DDR) and the cytosolic DNA sensing protein (CDSP) pathways, the latter upon release of the DSBs to the cytosol. The CDSP pathway activates NFκB and IRF3, which induce the expression of the pro-inflammatory genes. There is scant data on the activation of the CDSP pathway in human hearts with dilated cardiomyopathy (DCM). Aim We aimed to determine expression levels of selected components of the CDSP pathway in human hearts with DCM. Methods The DNA strand breaks were detected by the single-cell gel electrophoresis or the comet assay and expression of selected proteins by immunoblotting. Transcript levels were quantified in the RNA-Seq data. Results Single-cell gel electrophoresis showed an approximately 2-fold increase in the number of COMET cells in the DCM hearts. Immunoblotting showed increased levels of cyclic GMP-AMP synthase (CGAS), the canonical CDSP; TANK-binding kinase 1 (TBK1), an intermediary kinase in the pathway; and RELB, P52, and P50 components of the NFκB pathway in human heart samples from patients with DCM. Likewise, transcript levels of over 2 dozen genes involved in inflammatory responses were increased. Conclusions The findings provide the first set of evidence for the activation of the CDSP pathway in human hearts with DCM. The data in conjunction with the previous evidence of activation of the DDR pathway implicate the DSBs in the pathogenesis of human DCM.
Collapse
Affiliation(s)
- Leila Rouhi
- Center for Cardiovascular Genetics, Institute of Molecular Medicine, The University of Texas Health Science Center. Houston TX 77030, USA
| | - Sirisha M Cheedipudi
- Center for Cardiovascular Genetics, Institute of Molecular Medicine, The University of Texas Health Science Center. Houston TX 77030, USA
| | - Benjamin Cathcart
- Center for Cardiovascular Genetics, Institute of Molecular Medicine, The University of Texas Health Science Center. Houston TX 77030, USA
| | - Priyatansh Gurha
- Center for Cardiovascular Genetics, Institute of Molecular Medicine, The University of Texas Health Science Center. Houston TX 77030, USA
| | - Ali J Marian
- Center for Cardiovascular Genetics, Institute of Molecular Medicine, The University of Texas Health Science Center. Houston TX 77030, USA
| |
Collapse
|
2
|
Chen SN, Lombardi R, Karmouch J, Tsai JY, Czernuszewicz G, Taylor MRG, Mestroni L, Coarfa C, Gurha P, Marian AJ. DNA Damage Response/TP53 Pathway Is Activated and Contributes to the Pathogenesis of Dilated Cardiomyopathy Associated With LMNA (Lamin A/C) Mutations. Circ Res 2019; 124:856-873. [PMID: 30696354 DOI: 10.1161/circresaha.118.314238] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
RATIONALE Mutations in the LMNA gene, encoding LMNA (lamin A/C), are responsible for laminopathies. Dilated cardiomyopathy (DCM) is a major cause of mortality and morbidity in laminopathies. OBJECTIVE To gain insights into the molecular pathogenesis of DCM in laminopathies. METHODS AND RESULTS We generated a tet-off bigenic mice expressing either a WT (wild type) or a mutant LMNA (D300N) protein in cardiac myocytes. LMNAD300N mutation is associated with DCM in progeroid syndromes. Expression of LMNAD300N led to severe myocardial fibrosis, apoptosis, cardiac dysfunction, and premature death. Administration of doxycycline suppressed LMNAD300N expression and prevented the phenotype. Whole-heart RNA sequencing in 2-week-old WT and LMNAD300N mice led to identification of ≈6000 differentially expressed genes. Gene Set Enrichment and Hallmark Pathway analyses predicted activation of E2F (E2F transcription factor), DNA damage response, TP53 (tumor protein 53), NFκB (nuclear factor κB), and TGFβ (transforming growth factor-β) pathways, which were validated by Western blotting, quantitative polymerase chain reaction of selected targets, and immunofluorescence staining. Differentially expressed genes involved cell death, cell cycle regulation, inflammation, and epithelial-mesenchymal differentiation. RNA sequencing of human hearts with DCM associated with defined LMNA pathogenic variants corroborated activation of the DNA damage response/TP53 pathway in the heart. Increased expression of CDKN2A (cyclin-dependent kinase inhibitor 2A)-a downstream target of E2F pathway and an activator of TP53-provided a plausible mechanism for activation of the TP53 pathway. To determine pathogenic role of TP53 pathway in DCM, Tp53 gene was conditionally deleted in cardiac myocytes in mice expressing the LMNAD300N protein. Deletion of Tp53 partially rescued myocardial fibrosis, apoptosis, proliferation of nonmyocyte cells, left ventricular dilatation and dysfunction, and slightly improved survival. CONCLUSIONS Cardiac myocyte-specific expression of LMNAD300N, associated with DCM, led to pathogenic activation of the E2F/DNA damage response/TP53 pathway in the heart and induction of myocardial fibrosis, apoptosis, cardiac dysfunction, and premature death. The findings denote the E2F/DNA damage response/TP53 axis as a responsible mechanism for DCM in laminopathies and as a potential intervention target.
Collapse
Affiliation(s)
- Suet Nee Chen
- From the Center for Cardiovascular Genetics, Institute of Molecular Medicine, University of Texas Health Sciences Center at Houston (S.N.C., R.L., J.K., J.-Y.T., G.C., P.G., A.J.M.).,Section of Cardiology, University of Colorado-Anschutz Medical Campus, Denver (S.N.C., M.R.G.T., L.M.)
| | - Raffaella Lombardi
- From the Center for Cardiovascular Genetics, Institute of Molecular Medicine, University of Texas Health Sciences Center at Houston (S.N.C., R.L., J.K., J.-Y.T., G.C., P.G., A.J.M.).,Division of Cardiology, Department of Advanced Biomedical Science, University of Naples Federico II, Italy (R.L.)
| | - Jennifer Karmouch
- From the Center for Cardiovascular Genetics, Institute of Molecular Medicine, University of Texas Health Sciences Center at Houston (S.N.C., R.L., J.K., J.-Y.T., G.C., P.G., A.J.M.).,MD Anderson Cancer Center, Houston, TX (J.K.)
| | - Ju-Yun Tsai
- From the Center for Cardiovascular Genetics, Institute of Molecular Medicine, University of Texas Health Sciences Center at Houston (S.N.C., R.L., J.K., J.-Y.T., G.C., P.G., A.J.M.).,Thermo Fisher Scientific, Taiwan (J.-Y.T.)
| | - Grace Czernuszewicz
- From the Center for Cardiovascular Genetics, Institute of Molecular Medicine, University of Texas Health Sciences Center at Houston (S.N.C., R.L., J.K., J.-Y.T., G.C., P.G., A.J.M.)
| | - Matthew R G Taylor
- Section of Cardiology, University of Colorado-Anschutz Medical Campus, Denver (S.N.C., M.R.G.T., L.M.)
| | - Luisa Mestroni
- Section of Cardiology, University of Colorado-Anschutz Medical Campus, Denver (S.N.C., M.R.G.T., L.M.)
| | - Cristian Coarfa
- Department of Cell Biology, Baylor College of Medicine, Houston, TX (C.C.)
| | - Priyatansh Gurha
- From the Center for Cardiovascular Genetics, Institute of Molecular Medicine, University of Texas Health Sciences Center at Houston (S.N.C., R.L., J.K., J.-Y.T., G.C., P.G., A.J.M.)
| | - Ali J Marian
- From the Center for Cardiovascular Genetics, Institute of Molecular Medicine, University of Texas Health Sciences Center at Houston (S.N.C., R.L., J.K., J.-Y.T., G.C., P.G., A.J.M.)
| |
Collapse
|
3
|
Bhide S, Trujillo AS, O'Connor MT, Young GH, Cryderman DE, Chandran S, Nikravesh M, Wallrath LL, Melkani GC. Increasing autophagy and blocking Nrf2 suppress laminopathy-induced age-dependent cardiac dysfunction and shortened lifespan. Aging Cell 2018; 17:e12747. [PMID: 29575479 PMCID: PMC5946079 DOI: 10.1111/acel.12747] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/10/2018] [Indexed: 12/16/2022] Open
Abstract
Mutations in the human LMNA gene cause a collection of diseases known as laminopathies. These include myocardial diseases that exhibit age-dependent penetrance of dysrhythmias and heart failure. The LMNA gene encodes A-type lamins, intermediate filaments that support nuclear structure and organize the genome. Mechanisms by which mutant lamins cause age-dependent heart defects are not well understood. To address this issue, we modeled human disease-causing mutations in the Drosophila melanogaster Lamin C gene and expressed mutant Lamin C exclusively in the heart. This resulted in progressive cardiac dysfunction, loss of adipose tissue homeostasis, and a shortened adult lifespan. Within cardiac cells, mutant Lamin C aggregated in the cytoplasm, the CncC(Nrf2)/Keap1 redox sensing pathway was activated, mitochondria exhibited abnormal morphology, and the autophagy cargo receptor Ref2(P)/p62 was upregulated. Genetic analyses demonstrated that simultaneous over-expression of the autophagy kinase Atg1 gene and an RNAi against CncC eliminated the cytoplasmic protein aggregates, restored cardiac function, and lengthened lifespan. These data suggest that simultaneously increasing rates of autophagy and blocking the Nrf2/Keap1 pathway are a potential therapeutic strategy for cardiac laminopathies.
Collapse
Affiliation(s)
- Shruti Bhide
- Department of Biology, Molecular Biology and Heart Institutes; San Diego State University; San Diego CA USA
| | - Adriana S. Trujillo
- Department of Biology, Molecular Biology and Heart Institutes; San Diego State University; San Diego CA USA
| | - Maureen T. O'Connor
- Department of Biochemistry; Carver College of Medicine; University of Iowa; Iowa City IA USA
| | - Grant H. Young
- Department of Biochemistry; Carver College of Medicine; University of Iowa; Iowa City IA USA
| | - Diane E. Cryderman
- Department of Biochemistry; Carver College of Medicine; University of Iowa; Iowa City IA USA
| | - Sahaana Chandran
- Department of Biology, Molecular Biology and Heart Institutes; San Diego State University; San Diego CA USA
| | - Mastaneh Nikravesh
- Department of Biology, Molecular Biology and Heart Institutes; San Diego State University; San Diego CA USA
| | - Lori L. Wallrath
- Department of Biochemistry; Carver College of Medicine; University of Iowa; Iowa City IA USA
| | - Girish C. Melkani
- Department of Biology, Molecular Biology and Heart Institutes; San Diego State University; San Diego CA USA
| |
Collapse
|