“…We (Patel et al, 2019) and others (Chung et al, 2017; Dong et al, 2015; Laeger et al, 2014) have shown that activation of the ISR (via nutritional, genetic or pharmacological stressors) is associated with increased expression of growth differentiation factor 15 (GDF15) and fibroblast growth factor 21 (FGF21). Plasma levels of both FGF21 (Gómez-Ambrosi et al, 2017; Kharitonenkov et al, 2005; Kralisch et al, 2013; Reinehr et al, 2012; Zhang et al, 2008) and GDF15 (Carballo-Casla et al, 2021; Vila et al, 2011; Xiong et al, 2017) are known to be increased in obese humans and rodents as well as in other metabolic disease states such as insulin resistance (Chavez et al, 2009; Kempf et al, 2012), NAFLD (Bilson et al, 2021; Dushay et al, 2010; Galuppo et al, 2022; Kim et al, 2018; Rusli et al, 2016; Tucker et al, 2019) and mitochondrial disease (Poulsen et al, 2020; Suomalainen et al, 2011). Both stress-induced cytokines, GDF15 and FGF21, have attracted considerable interest as potential therapies for obesity and its associated metabolic disease (Keipert and Ost, 2021).…”