Fasting reduces glucose levels and protects mice against chemotoxicity, yet drugs that promote hyperglycemia are widely used in cancer treatment. Here, we show that dexamethasone (Dexa) and rapamycin (Rapa), commonly administered to cancer patients, elevate glucose and sensitize cardiomyocytes and mice to the cancer drug doxorubicin (DXR). Such toxicity can be reversed by reducing circulating glucose levels by fasting or insulin. Furthermore, glucose injections alone reversed the fasting-dependent protection against DXR in mice, indicating that elevated glucose mediates, at least in part, the sensitizing effects of rapamycin and dexamethasone. In yeast, glucose activates protein kinase A (PKA) to accelerate aging by inhibiting transcription factors Msn2/4. Here, we show that fasting or glucose restriction (GR) regulate PKA and AMP-activated protein kinase (AMPK) to protect against DXR in part by activating the mammalian Msn2/4 ortholog early growth response protein 1 (EGR1). Increased expression of the EGR1-regulated cardioprotective peptides atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) in heart tissue may also contribute to DXR resistance. Our findings suggest the existence of a glucose-PKA pathway that inactivates conserved zinc finger stress-resistance transcription factors to sensitize cells to toxins conserved from yeast to mammals. Our findings also describe a toxic role for drugs widely used in cancer treatment that promote hyperglycemia and identify dietary interventions that reverse these effects.
- MeSH
- atriální natriuretický faktor metabolismus MeSH
- časové faktory MeSH
- cytoprotekce účinky léků MeSH
- dexamethason farmakologie MeSH
- dieta MeSH
- fyziologický stres účinky léků MeSH
- glukosa farmakologie MeSH
- hyperglykemie patologie MeSH
- kardiotoxiny toxicita MeSH
- metformin farmakologie MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- natriuretický peptid typu B metabolismus MeSH
- omezení příjmu potravy metabolismus MeSH
- protein 1 časné růstové odpovědi metabolismus MeSH
- proteinkinasy aktivované AMP metabolismus MeSH
- proteinkinasy závislé na cyklickém AMP metabolismus MeSH
- protinádorové látky farmakologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH