REN and liver dysplastic nodule: Whilst the role of miRNA in the pathogenesis of DN has been extensively reviewed by others in relation to growth factors and fibrosis in DN, the focus of this review is on the role of miRNA in the renin-angiotensin system and the AGE/RAGE signalling pathway, and their downstream the mediators such as oxidative stress and the immune response in the context of diabetic nephropathy.