TY - JOUR
T1 - Diabetes Induces Cardiac Fibroblast Activation, Promoting a Matrix-Preserving Nonmyofibroblast Phenotype, Without Stimulating Pericyte to Fibroblast Conversion
AU - Alex, Linda
AU - Tuleta, Izabela
AU - Hanna, Anis
AU - Frangogiannis, Nikolaos G.
N1 - Publisher Copyright:
© 2023 The Authors.
PY - 2023/3/21
Y1 - 2023/3/21
N2 - BACKGROUND: Interstitial and perivascular fibrosis may contribute to diabetes-associated heart failure. Pericytes can convert to fibroblasts under conditions of stress and have been implicated in the pathogenesis of fibrotic diseases. We hypothesized that in diabetic hearts, pericytes may convert to fibroblasts, contributing to fibrosis and to the development of diastolic dysfunction. METHODS AND RESULTS: Using pericyte:fibroblast dual reporter (NG2Dsred [neuron-glial antigen 2 red fluorescent protein variant]; PDGFRαEGFP [platelet-derived growth factor receptor alpha enhanced green fluorescent protein]) mice in a type 2 diabetic db/db background, we found that diabetes does not significantly affect pericyte density but reduces the myocardial pericyte:fibroblast ratio. Lineage tracing using the inducible NG2CreER driver, along with reliable labeling of fibroblasts with the PDGFRα reporter system, showed no significant pericyte to fibroblast conversion in lean and db/db hearts. In addition, db/db mouse cardiac fibroblasts did not undergo myofibroblast conversion and had no significant induction of structural collagens but exhibited a matrix-preserving phenotype, associated with increased expression of antiproteases, matricellular genes, matrix cross-linking enzymes, and the fibrogenic transcription factor cMyc. In contrast, db/db mouse cardiac pericytes had increased expression of Timp3, without any changes in expression of other fibrosis-associated genes. The matrix-preserving phenotype of diabetic fibroblasts was associated with induction of genes encoding oxidative (Ptgs2/cycloxygenase-2, and Fmo2) and antioxidant proteins (Hmox1, Sod1). In vitro, high glucose partially recapitulated the in vivo changes in diabetic fibroblasts. CONCLUSIONS: Diabetic fibrosis is not mediated through pericyte to fibroblast conversion but involves acquisition of a matrix-preserving fibroblast program, which is independent of myofibroblast conversion and is only partially explained by the effects of the hyperglycemic environment.
AB - BACKGROUND: Interstitial and perivascular fibrosis may contribute to diabetes-associated heart failure. Pericytes can convert to fibroblasts under conditions of stress and have been implicated in the pathogenesis of fibrotic diseases. We hypothesized that in diabetic hearts, pericytes may convert to fibroblasts, contributing to fibrosis and to the development of diastolic dysfunction. METHODS AND RESULTS: Using pericyte:fibroblast dual reporter (NG2Dsred [neuron-glial antigen 2 red fluorescent protein variant]; PDGFRαEGFP [platelet-derived growth factor receptor alpha enhanced green fluorescent protein]) mice in a type 2 diabetic db/db background, we found that diabetes does not significantly affect pericyte density but reduces the myocardial pericyte:fibroblast ratio. Lineage tracing using the inducible NG2CreER driver, along with reliable labeling of fibroblasts with the PDGFRα reporter system, showed no significant pericyte to fibroblast conversion in lean and db/db hearts. In addition, db/db mouse cardiac fibroblasts did not undergo myofibroblast conversion and had no significant induction of structural collagens but exhibited a matrix-preserving phenotype, associated with increased expression of antiproteases, matricellular genes, matrix cross-linking enzymes, and the fibrogenic transcription factor cMyc. In contrast, db/db mouse cardiac pericytes had increased expression of Timp3, without any changes in expression of other fibrosis-associated genes. The matrix-preserving phenotype of diabetic fibroblasts was associated with induction of genes encoding oxidative (Ptgs2/cycloxygenase-2, and Fmo2) and antioxidant proteins (Hmox1, Sod1). In vitro, high glucose partially recapitulated the in vivo changes in diabetic fibroblasts. CONCLUSIONS: Diabetic fibrosis is not mediated through pericyte to fibroblast conversion but involves acquisition of a matrix-preserving fibroblast program, which is independent of myofibroblast conversion and is only partially explained by the effects of the hyperglycemic environment.
KW - cardiomyopathy
KW - diabetes
KW - fibroblasts
KW - hyperglycemia
KW - lineage tracing
KW - pericytes
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U2 - 10.1161/JAHA.122.027463
DO - 10.1161/JAHA.122.027463
M3 - Article
C2 - 36892073
AN - SCOPUS:85150751103
SN - 2047-9980
VL - 12
JO - Journal of the American Heart Association
JF - Journal of the American Heart Association
IS - 6
M1 - e027463
ER -