The previous reports showed the decreased protein expressions of TJPs (claudin-1, occludin, zonula occludens-1) in the colonic mucosa in CKD model rat and the decreased expression of TJPs (claudin-5, occludin, Junctional adhesion molecule-1) in immunofluorescent staining of subcutaneous fat biopsies from CKD patients [48, 49]. Here, OCLN is linked to chronic kidney disease.