In that study of the effects of the periodontal pathogen P. gingivalis lipopolysaccharide (LPS) which is a ligand of TLR2 and TLR4 in diabetic nephropathy, all diabetic mice subjected to repeated LPS administrations were euthanized within the survival period of all of the diabetic mice not administered LPS and of the survival period of all of the non-diabetic LPS-administered mice. Here, TLR4 is linked to diabetic kidney disease.