CCL2 and Cognitive impairment: Additionally, oxidative stress impairs energy metabolism, particularly in the energy-sensitive hippocampus (Sies, 2015), and promotes inflammation, as evidenced by elevated levels of chemokine motif chemokine ligand 2 (CCL-2) in depression, linked to cognitive deficits and abnormal Aβ metabolism in AD (Romo-Araiza and Ibarra, 2020; Stuart and Baune, 2014; Westin et al., 2012).