Chemotherapy for the brain: the antitumor antibiotic mithramycin prolongs survival in a mouse model of Huntington's disease.
Huntington's disease (HD) is a fully penetrant autosomal-dominant inherited neurological disorder caused by expanded CAG repeats in the Huntingtin gene. Transcriptional dysfunction, excitotoxicity, and oxidative stress have all been proposed to play important roles in the pathogenesis of HD. This study was designed to explore the therapeutic potential of mithramycin, a clinically approved guanosine-cytosine-rich DNA binding antitumor antibiotic. Pharmacological treatment of a transgenic mouse model of HD (R6/2) with mithramycin extended survival by 29.1%, greater than any single agent reported to date. Increased survival was accompanied by improved motor performance and markedly delayed neuropathological sequelae. To identify the functional mechanism for the salubrious effects of mithramycin, we examined transcriptional dysfunction in R6/2 mice. Consistent with transcriptional repression playing a role in the pathogenesis of HD, we found increased methylation of lysine 9 in histone H3, a well established mechanism of gene silencing. Mithramycin treatment prevented the increase in H3 methylation observed in R6/2 mice, suggesting that the enhanced survival and neuroprotection might be attributable to the alleviation of repressed gene expression vital to neuronal function and survival. Because it is Food and Drug Administration-approved, mithramycin is a promising drug for the treatment of HD.
Ferrante
Robert J
RJ
Geriatric Research and Education and Clinical Center, Veterans Administration Medical Center, Bedford, MA, USA.
Ryu
Hoon
H
Kubilus
James K
JK
D'Mello
Santosh
S
Sugars
Katharine L
KL
Lee
Junghee
J
Lu
Peiyuan
P
Smith
Karen
K
Browne
Susan
S
Beal
M Flint
MF
Kristal
Bruce S
BS
Stavrovskaya
Irina G
IG
Hewett
Sandra
S
Rubinsztein
David C
DC
Langley
Brett
B
Ratan
Rajiv R
RR
D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology / Q000627:therapeutic use*; D001921:Brain / Q000473:pathology; D002478:Cells, Cultured; D020868:Gene Silencing; D006801:Humans; D000071058:Huntingtin Protein; D006816:Huntington Disease / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D066298:In Vitro Techniques; D008239:Lysine / Q000378:metabolism; D008297:Male; D008745:Methylation; D051379:Mice; D008822:Mice, Transgenic; D008930:Mitochondria, Liver / Q000187:drug effects / Q000378:metabolism; D009043:Motor Activity / Q000187:drug effects; D016202:N-Methylaspartate / Q000494:pharmacology; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000235:genetics; D009474:Neurons / Q000166:cytology / Q000187:drug effects; D009687:Nuclear Proteins / Q000096:biosynthesis / Q000235:genetics; D008926:Plicamycin / Q000494:pharmacology / Q000627:therapeutic use*; D051381:Rats; D011914:Rats, Inbred BN; D011916:Rats, Inbred F344; D017470:Receptors, Glutamate / Q000187:drug effects / Q000502:physiology; D014158:Transcription, Genetic
D000903:Antibiotics, Antineoplastic; C086055:HTT protein, human; C506812:Htt protein, mouse; C499524:Htt protein, rat; D000071058:Huntingtin Protein; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D017470:Receptors, Glutamate; D016202:N-Methylaspartate; D008239:Lysine; D008926:Plicamycin