a potential strategy to prevent Dox-induced cardiotoxicity. Future research should aim to determine the optimal regimen of fasting, confirmation that this regimen does not interfere with the antitumor properties of Dox, as well as the underlying mechanisms exerting the cardioprotective effects.© 2014 Baishideng Publishing Group Inc. All rights reserved.Key words: Fasting; Doxorubicin; Cardiotoxicity; Cardioprotection Core tip: Doxorubicin (Dox)-induced cardiotoxicity remains a significant cause of morbidity and mortality in cancer survivors, despite the intensive investigation of potential protective strategies. Studies have shown that shortterm fasting induces cardioprotective effects against Doxinduced injury. Importantly, evidence suggests that fasting may enhance the antitumor effects of Dox. Thus, shortterm fasting may be a feasible practice that can easily be incorporated into the treatment plans of cancer patients. Abstract Doxorubicin (Dox) is one of the most effective chemotherapeutic agents used in the treatment of several types of cancer. However the use is limited by cardiotoxicity. Despite extensive investigation into the mechanisms of toxicity and preventative strategies, Dox-induced cardiotoxicity still remains a major cause of morbidity and mortality in cancer survivors. Thus, continued research into preventative strategies is vital. Short-term fasting has proven to be cardioprotective against a variety of insults. Despite the potential, only a few studies have been conducted investigating its ability to prevent Dox-induced cardiotoxicity. However, all show proof-of-principle that short-term fasting is cardioprotective against Dox. Fasting affects a plethora of cellular processes making it difficult to discern the mechanism(s) translating fasting to cardioprotection, but may involve suppression of insulin and insulin-like growth factor-1 signaling with stimulated autophagy. It is likely that additional mechanisms also contribute. Importantly, the literature suggests that fasting may enhance the antitumor activity of Dox. Thus, fasting is a regimen that warrants further investigation as

BackgroundDoxorubicin treatment is known to cause muscular weakness. However, the cellular mechanisms have not been elucidated. We aimed to determine the effects of acute doxorubicin treatment on proteome lysine acetylation status, an indication of the apoptotic and inflammatory environment, and the expression and activation of various apical caspases involved in the initiation of apoptosis.MethodsSix-week-old male F344 rats were injected intraperitoneally with 20 mg/kg of doxorubicin or saline. Once the treatment was administered, both groups of animals were fasted with no food or water until sacrifice 24 h posttreatment.ResultsDoxorubicin treatment affected neither the proteome lysine acetylation status nor the expression of sirtuin 1, sirtuin 3, SOD1, or SOD2 in soleus of fasted animals. Doxorubicin treatment also did not affect the expression or activation of procaspase-1, procaspase-8, procaspase-9, or procaspase−12.ConclusionWe suggest that doxorubicin does not exert a direct effect on these catabolic parameters in skeletal muscle in vivo.

Molecular technologies have produced diverse arrays of animal models for studying genetic diseases and potential therapeutics. Many have neonatal phenotypes. Spinal muscular atrophy (SMA) is a neuromuscular disorder primarily affecting children, and is of great interest in translational medicine. The most widely used SMA mouse models require all phenotyping to be performed in neonates since they do not survive much past weaning. Pre-clinical studies in neonate mice can be hindered by toxicity and a lack of quality phenotyping assays, since many assays are invalid in pups or require subjective scoring with poor inter-rater variability. We find, however, that passive electrocardiography (ECG) recording in conscious 11-day old SMA mice provides sensitive outcome measures, detecting large differences in heart rate, cardiac conduction, and autonomic control resulting from disease. We find significant drug benefits upon treatment with G418, an aminoglycoside targeting the underlying protein deficiency, even in the absence of overt effects on growth and survival. These findings provide several quantitative physiological biomarkers for SMA preclinical studies, and will be of utility to diverse disease models featuring neonatal cardiac arrhythmias.

Early effects of Dox involve hepatic proteome lysine deacetylation and caspase-12 activation under these experimental conditions.

Doxorubicin (DOX) is a chemotherapeutic agent known to cause cardiac and hepatic toxicity. Mechanisms of toxicity include induction of oxidative stress and apoptosis. While mechanisms of cardiotoxicity have been extensively studied, much less is known about hepatic toxicity. Although the effect of DOX on markers of oxidative stress in the liver has been previously described, none of the studies controlled for the anorexic effects of DOX. Anorexia can deplete glutathione and cause oxidative stress in the liver. Thus, we aimed to delineate the effects of DOX‐induced oxidative stress from the effects of anorexia. Furthermore, the effect of DOX on vitamin D receptor (VDR) expression is not known. Therefore, a second aim was to make this determination. Male F344 rats were injected IP with 20 mg/kg of DOX or saline. Once treated, all animals were fasted with no food or water until sacrifice 24 hours later. Total glutathione content was elevated and protein carbonyls were decreased, with no change in Mn superoxide dismutase content, compared to control animals at 24 hr post treatment. These results differ from those previously reported and may be due to the differences in experimental design. Furthermore, content of VDR was increased in the DOX group compared to controls. In summary, improved oxidative stress status and increased VDR expression at 24 hr may be due to a rebound response.