In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: In conclusion , HFD - induced obese rats are highly sensitized to doxorubicin - induced cardiotoxicity by substantially downregulating cardiac mitochondrial ATP generation , increasing oxidative stress and downregulating the JAK / STAT3 pathway .
### Output Text:
In conclusion , HFD - induced obese rats are highly sensitized to <span class="chemical">doxorubicin</span> - induced cardiotoxicity by substantially downregulating cardiac mitochondrial <span class="chemical">ATP</span> generation , increasing oxidative stress and downregulating the JAK / STAT3 pathway . 