CCL2 and diabetic kidney disease: The protein kinase C-α and polyol and hexosamine pathways are activated, upregulating ROS production and increasing the expression of the associated inflammatory factors interleukin (IL) 6, monocyte chemoattractant protein-1, tumour necrosis factor alpha and intercellular adhesion molecule-1 in DKD, accelerating the progress of DKD (Wu X. Q. et al., 2021; Dusabimana et al., 2021; Jha et al., 2022).