Response by Wu et al to Letter Regarding Article, "Glucose-Sensitive Myokine/Cardiokine MG53 Regulates Systemic Insulin Response and Metabolic Homeostasis". Issue 6 (6th August 2019) - Wu, Hong-Kun; Zhang, Yan; Chen, Gengjia; Hu, Xinli; Lv, Fengxiang; Xiao, Rui-Ping