Dystrophic muscle improvement in zebrafish via increased heme oxygenase signaling.
Duchenne muscular dystrophy (DMD) is caused by a lack of the dystrophin protein and has no effective treatment at present. Zebrafish provide a powerful in vivo tool for high-throughput therapeutic drug screening for the improvement of muscle phenotypes caused by dystrophin deficiency. Using the dystrophin-deficient zebrafish, sapje, we have screened a total of 2640 compounds with known modes of action from three drug libraries to identify modulators of the disease progression. Six compounds that target heme oxygenase signaling were found to rescue the abnormal muscle phenotype in sapje and sapje-like, while upregulating the inducible heme oxygenase 1 (Hmox1) at the protein level. Direct Hmox1 overexpression by injection of zebrafish Hmox1 mRNA into fertilized eggs was found to be sufficient for a dystrophin-independent restoration of normal muscle via an upregulation of cGMP levels. In addition, treatment of mdx(5cv) mice with the PDE5 inhibitor, sildenafil, which was one of the six drugs impacting the Hmox1 pathway in zebrafish, significantly increased the expression of Hmox1 protein, thus making Hmox1 a novel target for the improvement of dystrophic symptoms. These results demonstrate the translational relevance of our zebrafish model to mammalian models and support the use of zebrafish to screen for new drugs to treat human DMD. The discovery of a small molecule and a specific therapeutic pathway that might mitigate DMD disease progression could lead to significant clinical implications.
Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA, USA.
Genri
G
Kawahara
Molly J
MJ
Gasperini
Jennifer A
JA
Myers
Jeffrey J
JJ
Widrick
Alal
A
Eran
Peter R
PR
Serafini
Matthew S
MS
Alexander
Mathew T
MT
Pletcher
Carl A
CA
Morris
Louis M
LM
Kunkel
D000818:Animals; D006152:Cyclic GMP / Q000096:biosynthesis; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5 / Q000378:metabolism*; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical; D016189:Dystrophin / Q000172:deficiency / Q000235:genetics*; D051547:Heme Oxygenase-1 / Q000096:biosynthesis* / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D020388:Muscular Dystrophy, Duchenne / Q000188:drug therapy*; D058986:Phosphodiesterase 5 Inhibitors / Q000494:pharmacology; D010879:Piperazines / Q000494:pharmacology; D011687:Purines / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics; D015398:Signal Transduction / Q000235:genetics; D000068677:Sildenafil Citrate; D013450:Sulfones / Q000494:pharmacology; D015854:Up-Regulation; D015027:Zebrafish / Q000235:genetics
D016189:Dystrophin; D058986:Phosphodiesterase 5 Inhibitors; D010879:Piperazines; D011687:Purines; D012333:RNA, Messenger; D013450:Sulfones; D000068677:Sildenafil Citrate; C496541:HMOX1 protein, human; D051547:Heme Oxygenase-1; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5; C517382:Pde5a protein, mouse; D006152:Cyclic GMP