title: Effects of different small HSPB members on contractile dysfunction and structural changes in a Drosophila melanogaster model for Atrial Fibrillation.
abstract: The most common clinical tachycardia, Atrial Fibrillation (AF), is a progressive disease, caused by cardiomyocyte remodeling, which finally results in contractile dysfunction and AF persistence. Recently, we identified a protective role of heat shock proteins (HSPs), especially the small HSPB1 member, against tachycardia remodeling in experimental AF models. Our understanding of tachycardia remodeling and anti-remodeling drugs is currently hampered by the lack of suitable (genetic) manipulatable in vivo models for rapid screening of key targets in remodeling. We hypothesized that Drosophila melanogaster can be exploited to study tachycardia remodeling and protective effects of HSPs by drug treatments or by utilizing genetically manipulated small HSP-overexpressing strains. Tachypacing of Drosophila pupae resulted in gradual and significant cardiomyocyte remodeling, demonstrated by reduced contraction rate, increase in arrhythmic episodes and reduction in heart wall shortening, compared to normal paced pupae. Heat shock, or pre-treatment with HSP-inducers GGA and BGP-15, resulted in endogenous HSP overexpression and protection against tachycardia remodeling. DmHSP23 overexpressing Drosophilas were protected against tachycardia remodeling, in contrast to overexpression of other small HSPs (DmHSP27, DmHSP67Bc, DmCG4461, DmCG7409, and DmCG14207). (Ultra)structural evaluation of the tachypaced heart wall revealed loss of sarcomeres and mitochondrial damage which were absent in tachypaced DmHSP23 overexpressing Drosophila. In addition, tachypacing induced a significant increase in calpain activity, which was prevented in tachypaced Drosophila overexpressing DmHSP23. Tachypacing of Drosophila resulted in cardiomyocyte remodeling, which was prevented by general HSP-inducing treatments and overexpression of a single small HSP, DmHSP23. Thus, tachypaced D. melanogaster can be used as an in vivo model system for rapid identification of novel targets to combat AF associated cardiomyocyte remodeling.
authors: Department of Clinical Pharmacology, University Institute for Drug Exploration, University of Groningen, University Medical Center Groningen, The Netherlands.
authors: Deli
authors: D
authors: Zhang
authors: Lei
authors: L
authors: Ke
authors: Katarina
authors: K
authors: Mackovicova
authors: Johannes J L
authors: JJ
authors: Van Der Want
authors: Ody C M
authors: OC
authors: Sibon
authors: Robert M
authors: RM
authors: Tanguay
authors: Genevieve
authors: G
authors: Morrow
authors: Robert H
authors: RH
authors: Henning
authors: Harm H
authors: HH
authors: Kampinga
authors: Bianca J J M
authors: BJ
authors: Brundel
mesh_terms: D000818:Animals; D001281:Atrial Fibrillation / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology*; D002154:Calpain / Q000378:metabolism; D004195:Disease Models, Animal; D004224:Diterpenes / Q000494:pharmacology; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D004331:Drosophila melanogaster / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects; D006321:Heart / Q000503:physiopathology; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D050888:Heat-Shock Proteins, Small / Q000235:genetics / Q000378:metabolism*; D009200:Myocardial Contraction / Q000235:genetics; D010091:Oximes / Q000494:pharmacology; D010880:Piperidines / Q000494:pharmacology; D013610:Tachycardia / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control
chemical_list: D004224:Diterpenes; D029721:Drosophila Proteins; D006360:Heat-Shock Proteins; D050888:Heat-Shock Proteins, Small; C105998:Hsp23 protein, Drosophila; D010091:Oximes; D010880:Piperidines; D002154:Calpain; C405586:BGP 15; C031049:geranylgeranylacetone