Most of these studies affirm that the downregulation of the neurotrophin BDNF and its signaling through cAMP response element-binding (CREB) and TrkB as the main mechanism involved in HCD-induced AHN injury (Molteni et al., 2002; Hwang et al., 2008; White et al., 2009; Kim et al., 2021; Paulo et al., 2021). This evidence concerns the gene BDNF and heavy chain disease.