Doxorubicin (Dox) is a potent chemotherapeutic drug used for the treatment of various cancers. Unfortunately, its use is limited as Dox induces adverse cardiotoxicity (DIC) and muscle toxicity (DIMT), which are mediated through oxidative stress, ER stress, and inflammation. However, it remains unknown whether Dox induces an inflammation mediated cell death, called “pyroptosis”. The current study is designed to determine whether Dox induces pyroptosis in cardiac and muscle cell culture models. Moreover, the protective effects of embryonic stem cell-derived exosomes (ES-Exos) in inhibiting pyroptosis will also be determined. For this purpose, we designed two different cell culture models using H9c2 cadiomyoblasts and Sol 8 cells. For the DIC model, H9c2 were exposed to Dox to induce pyroptosis and then treated with exosomes. Cells were divided into 4 groups: Control, Dox, Dox+ES-Exos, and Dox+MEF-Exos (negative control). Furthermore, to generate the DIMT model, Sol 8 cells were incubated with Dox+THP-1 conditioned medium (TCM) to induce toxicity and inflammation, which was followed by exosomes treatment. We assigned cells into 5 groups: Control, Dox+TCM, Dox+TCM+ES-Exos, Dox+TCM+MEF-Exos (negative control), and Dox+TCM+ESExos+GW4869 compound (exosomes inhibitor, negative control). Our data shows that Dox treatment significantly increased pyroptotic marker expression including TLR-4, NLRP3, caspase-1, IL1-β, Caspase-11, and gasdermin-D as well as increased proinflammatory TNF-α and IL-6 expression in H9c2 cells. There was also a significant increase in caspase-1, IL1-β, and IL-18 expression in Dox+TCM treated Sol 8 cells. Conversely, increased pyroptosis and inflammation post-Dox treatment were inhibited by ES-Exos in both culture models. No significant changes observed upon MEF-Exos and GW4869 compound treatments. In conclusion, our data shows Dox induces pyroptosis and inflammation within cardiac and skeletal muscle cells, which can be inhibited following treatment with ES-exosomes. This is a novel study with new mechanistic observations on the pathophysiological role of pyroptosis in Dox-induced cardio and muscle toxicities.
Master of Science (M.S.)
College of Medicine
Length of Campus-only Access
Masters Thesis (Campus-only Access)
Tavakoli Dargani, Zahra, "Embryonic Stem Cell-Derived Exosomes Inhibit Doxorubicin-Induced Pyroptosis in Cell Culture Models" (2018). Electronic Theses and Dissertations. 6227.