Bio: Dr. Sun is an Assistant Professor at NYU Grossman School of Medicine, Division of Environmental Medicine. She received her doctorate in Cell Biology from Shanghai Institute of Cell Biology, Chinese Academy of Sciences, where she was trained in the field of Developmental and Cell biology. After that, Dr. Sun had her postdoctoral training at Mount Sinai School of Medicine, with the research focused on transcriptional regulation of stem cell pluripotency and cell differentiation. Since she joined NYU Department of Environmental Medicine, Dr. Sun’s research has been focused on the epigenetic reprogramming and dysregulation by environmental toxicants, including toxic metals and particulate matter, on cytotoxicity and malignant transformation, as well as their impact on human disease. Dr. Sun has published more than 60 papers in many different journals, including some high-profile journals.

Abstract: Hexavalent chromium, Cr(VI), is widely used in numerous industrial processes. Occupational or environmental exposures to Cr(VI) have been associated with a variety of adverse respiratory, cardiovascular, gastrointestinal, hematological, and hepatic effects. However, very little is known about the impact of Cr(VI) on skeletal muscles, the largest organ in the human body comprising about 40% of body mass. Our study explored the impact of Cr(VI) exposure on myogenic differentiation in vitro as well as muscle regeneration in vivo following cadiotoxin-induced muscle injury. Our results showed that acute exposure of C2C12 myoblasts or freshly isolated primary myoblasts to Cr(VI) inhibits myogenic differentiation in a dose-dependent manner. Moreover, the expression patterns of key myogenic regulatory factors including MyoD, MyoG, Mrf4 and Myf5 were significantly altered in Cr(VI)-treated cells. Furthermore, acute or subacute Cr(VI) exposure via drinking water at the same day of induced muscle injury resulted in a significant impairment in muscle regeneration. Taking together, our study generates valuable evidence supporting Cr(VI) exposure as a risk factor for muscle impairment, and provide critical insights for future intervention on skeletal muscle health and strength.