Global expression profiling identifies a novel biosignature for protein aggregation R120GCryAB cardiomyopathy in mice. Physiol Genomics 2008 Oct 08;35(2):165-72
Date
07/17/2008Pubmed ID
18628338Pubmed Central ID
PMC2575954DOI
10.1152/physiolgenomics.00297.2007Scopus ID
2-s2.0-57049087658 (requires institutional sign-in at Scopus site) 24 CitationsAbstract
Protein aggregation cardiomyopathy is a life-threatening manifestation of a multisystem disorder caused by the exchange mutation in the gene encoding the human small heat shock protein alphaB-crystallin (hR120GCryAB). Genetic studies in mice have established cardiac hR120GCryAB expression causes increased activity of glucose 6-phosphate dehydrogenase (G6PD) and "reductive stress" (Rajasekaran et al., Cell 130: 427-439, 2007). However, the initiating molecular events in the pathogenesis of this novel toxic gain-of-function mechanism remain poorly defined. In an integrated systems approach using gene expression profiling, we identified a "biosignature," whose features can be validated to predict the onset, rate of progression, and clinical outcome of R120GCryAB cardiomyopathy. At the 3 mo disease-related but compensated stage, we demonstrate that transcripts were only upregulated in three distinct pathways: stress response (e.g., Hsp70, Hsp90), glutathione metabolism (Gpx1, Gpx3, glutathione S-transferase), and complement and coagulation cascades in hR120GCryAB transgenic mouse hearts compared with either hCryAB WT transgenic mice or nontransgenic controls. In 6 mo old myopathic hearts, ribosomal synthesis and cellular remodeling associated with increased cardiac hypertrophy were additional upregulated pathways. In contrast, the predominant downregulated pathways were for oxidative phosphorylation, fatty acid metabolism, intermediate metabolism, and energetic balance, supporting their primary pathogenic roles by which G6PD-dependent reductive stress causes cardiac decompensation and overt heart failure in hR120GCryAB cardiomyopathy. This study extends and confirms our previous findings that reductive stress is a causal mechanism for hR120G CryAB cardiomyopathy and demonstrates that alteration in glutathione pathway gene expression is an early biosignature with utility for presymptomatic detection.
Author List
Rajasekaran NS, Firpo MA, Milash BA, Weiss RB, Benjamin IJAuthor
Ivor J. Benjamin MD Professor in the Medicine department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsArginine
Cardiomyopathies
Gene Expression Profiling
Glutathione
Glycine
Humans
Mice
Mice, Transgenic
Models, Animal
Oligonucleotide Array Sequence Analysis
alpha-Crystallin B Chain
