A lifespan-extending drug has limited effects on aging
The immunosuppressive drug rapamycin has been shown to increase longevity in mice even when treatment begins at an advanced age. It is unclear if the extension of life also correlates with prolonged health and vigor. In the current issue of the Journal of Clinical Investigation, Dan Ehninger and colleagues at the German Center for Neurodegenrative Diseases evaluated age-associated characteristics in mice treated with rapamycin. They found that rapamycin improved memory and spatial learning, reduced thyroid follicle size, and reduced body fat in older mice. However, many of these same attributes were also improved in young mice treated with the drug, indicating an age-independent drug effect. The prevalence of cancer, a common cause of mouse mortality, was also decreased in older treated mice. The authors did find that rapamycin treatment had no effect on several age related symptoms, including cardiovascular and liver function, loss of muscle mass, strength retention, or balance. These data suggest that rapamycin treatment may increase lifespan through reduction of cancer rates, and the drug may be useful for relief of some age related conditions. In the accompanying commentary, Arlan Richards of the University of Texas Health Science Center at San Antonio suggests that clinical trials to study the effect of rapamycin on age related neurodegenerative diseases of the elderly such as Alzheimer's disease should be considered.
TITLE: Rapamycin extends murine lifespan but has limited effects on aging
AUTHOR CONTACT:
Dan Ehninger
German Center for Neurodegenerative Diseases (DZNE), Bonn, UNK, DEU
Phone: +4922844302530; Fax: +4922844302689; E-mail: dan.ehninger@dzne.de
View this article at: http://www.jci.org/articles/view/67674?key=11202489766161120d01
ACCOMPANYING COMMENTARY
TITLE: Rapamycin, anti-aging, and avoiding the fate of Tithonus
AUTHOR CONTACT:
Arlan Richardson
University of Texas Health Sciences Center at San Antonio, San Antonio, TX, USA
Phone: 210-567-3800; E-mail: richardsona@uthscsa.edu
View this article at: http://www.jci.org/articles/view/70800?key=b519b711c5e5ee8e8f70
A molecular chaperon prevents antibiotic associated hearing loss
An underlying cause of hearing loss is the death of sensory hair cells in the inner ear, which can be damaged in response to a variety of factors including the use of aminoglycoside antibiotics. Previous research has shown that sensory hair cell death in response to antibiotic treatment can be prevented by triggering the expression of HSP70, a member of the heat shock family of proteins that are induced by cellular stress. In this issue of the Journal of Clinical Investigation, Lisa Cunningham and colleagues at the National Institutes of Health investigate the mechanism underlying the protective effect of HSP70 on antibiotic induced hair cell loss. This group found that HSP70 is produced and secreted by the supporting cells of the inner ear in response to heat shock. Extracellular HSP70 produced either by supporting cells or added exogenously prevented antibiotic induced hair cell death. In the companion commentary Rona Giffard and colleagues at the Stanford University School of Medicine point out that there are no current treatments for prevention of aminoglycoside induced hearing loss and that extracellular HSP70 has potential to be used therapeutically.
TITLE: Inner Ear Supporting Cells Protect Hair Cells by Secreting HSP70
AUTHOR CONTACT:
Lisa L. Cunningham
NIH/NIDCD, Rockville, MD, USA
Phone: 3014432766; E-mail: lisa.cunningham@nih.gov
View this article at: http://www.jci.org/articles/view/68480?key=b6cd99301eccb0bd1c83
ACCOMPANYING COMMENTARY
TITLE: The future of molecular chaperones and beyond
AUTHOR CONTACT:
Rona Giffard
Stanford School of Medicine, Stanford, CA, USA
Phone: 650-725-8482; Fax: 650 725 8052; E-mail: rona.giffard@stanford.edu
View this article at: http://www.jci.org/articles/view/70799?key=fb141d6d17a11e35f304
Adenosine therapy reduces seizures and progression of epilepsy
Epilepsy is characterized by recurrent seizures that present in many different ways. In some cases epileptic patients exhibit a progressive increase in both frequency and severity of seizures. Epigenetic changes such as DNA methylation have recently been implied as an underlying cause of several neurologic disorders, including epilepsy. In this issue of the Journal of Clinical Investigation, Detlev Boison and colleagues at Legacy Research show an increase of DNA methylation in the hippocampi of epileptic animals. They found that increased methyation corresponded with a decrease of adenosine (ADO), which is a known anticonvulsant. The authors used bioengineered implants to transiently deliver ADO to the brains of epileptic rats. Targeted ADO delivery to the brain reversed DNA hypermethylation and resulted in a decrease in seizures and prevented epilepsy progression. These data indicate that therapies aimed at reducing DNA methylation in the brain have potential for the treatment and prevention of epilepsy.
TITLE: Epigenetic changes induced by adenosine augmentation therapy prevent epileptogenesis
AUTHOR CONTACT:
Detlev Boison
Legacy Research, Portland, OR, USA
Phone: (503) 413-1754; Fax: (503) 413-5465; E-mail: dboison@downeurobiology.org
View this article at: http://www.jci.org/articles/view/65636?key=b830cd2835e7b6acdd11
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TITLE: Egr1 directs tendon differentiation and promotes tendon repair
AUTHOR CONTACT:
Delphine Duprez
CNRS, Paris, , FRA
Phone: + 33 (0)1 44 27 27 53; E-mail: delphine.duprez@upmc.fr
View this article at: http://www.jci.org/articles/view/67521?key=af6c849bdc7d14747ee0
TITLE: The nucleotide sugar UDP-glucose mobilizes long-term repopulating primitive hematopoietic cells
AUTHOR CONTACT:
Byeong Chel Lee
University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA
Phone: 412-623-2285; E-mail: leeb4@upmc.edu
View this article at: http://www.jci.org/articles/view/64060?key=c5222c4df362aae649a4
TITLE: Somitic disruption of GNAS in chick embryos mimics progressive osseous heteroplasia
AUTHOR CONTACT:
Li Zeng
Tufts University, Boston, MA, USA
Phone: 617-636-2107; E-mail: li.zeng@tufts.edu
View this article at: http://www.jci.org/articles/view/69746?key=6a47f4e50a4e5c869dd1
TITLE: Isocitrate ameliorates anemia by suppressing the erythroid iron restriction response
AUTHOR CONTACT:
Adam Goldfarb
University of Virginia, Charlottesville, VA, USA
Phone: 434-982-0593; Fax: 434-924-1545; E-mail: ang3x@virginia.edu
View this article at: http://www.jci.org/articles/view/68487?key=fb2570c16160d28f2c61
TITLE: CHIP protects against cardiac pressure overload through regulation of AMPK
AUTHOR CONTACT:
Cam Patterson
University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
Phone: 919-843-6477; Fax: 9198434585; E-mail: cpatters@med.unc.edu
View this article at: http://www.jci.org/articles/view/69080?key=558f7e86d3cc0eb445aa
TITLE: Immunoglobulin-like domain containing receptor 1 mediates fat-stimulated cholecystokinin secretion
AUTHOR CONTACT:
Rodger A. Liddle
Duke University Medical Center, Durham, NC, USA
Phone: 919 681-6380; E-mail: rodger.liddle@duke.edu
View this article at: http://www.jci.org/articles/view/68587?key=b4e895c08468c2462dcd
Journal
Journal of Clinical Investigation