TNF and diabetic kidney disease: Five (5/15) studies (17, 26, 27, 34, 37) reported inflammatory markers and intestinal barrier function between DKD and HC, and found that inflammatory indicators in patients with DKD were higher than those in HC (e.g.: IL-6 (17, 26, 27, 34, 37), CRP [increased in four studies (17, 26, 27, 37), and no statistical difference in one study (34)], TNFα (17, 34, 37), IL-8 (37), LPS [increased in one study (17) and no statistical difference in the other study (34)].