Effects of autophagy on macrophage adhesion and migration in diabetic nephropathy

Abstract

Objective: Macrophage infiltration in kidney is a major pathological feature of diabetic nephropathy (DN), which has been demonstrated associate with macrophages autophagy homeostasis. However, the relationships between autophagy and the infiltration response related of macrophages adhesion and migration are unknown. This study aims to investigate the impact of macrophages adhesion and migration by modulating autophagy. Methods: In vivo, rats were randomly distributed into control (NC) and DN groups. The pathological changes in renal tissue were assessed, and expression of CD68, LC3, P62 were analyzed. In vitro, RAW264.7 cells were divided into NC and high glucose (HG) groups. The capacity of macrophages adhesion migration and the expression of autophagy markers were observed with and without autophagy modulators (rapamycin, 3-methyladenine, chloroquine, and bafilomycin A1 for RAPA, 3-MA, CQ, BAFA). The macrophages autophagosome and the process of degradation and fusion of autophagosome-lysosome were observed by electron microscopy. Results: In vivo, renal injury is aggravated in diabetic rat compared with NC group. The autophagy level is inhibited in renal tissues of DN group with the increasing expression of CD68 and P62, while expression level of LC3 decreased ( p < .05). In vitro, HG and 3-MA reduce the numbers of autophagosome of macrophages to inhibit autophagy level with decrease expression of LC3 and Beclin-1, but increase expression of P62, which promote the adhesion and migration capacity of macrophages ( p < .05). Moreover, CQ and BAFA suppress autophagy level by inhibiting the process of autophagosome-lysosome degradation and fusion of macrophages, as well as the expression of LC3 and Beclin-1. We notice an increase expression of P62 by CQ and BAFA stimulation ( p < .05). CQ and BAFA further facilitate the adhesion and migration capacity of macrophages. However, RAPA increases the numbers of macrophages autophagosome that inhibited by HG, resulting in a recovery of autophagy level with increase expression of LC3 and Beclin-1, whereas a reduction expression of P62, which lead to inhibition of adhesion and migration of macrophages induced by HG ( p < .05) Conclusions: High glucose efficiently reduced the level of macrophage autophagy, following macrophages adhesion and migration enhanced when autophagy is suppressed. Activation of autophagosome improve the level of autophagy, but leading to a reduction of the macrophages adhesion and migration. While, inhibiting the process of degradation and fusion of autophagosome-lysosome suppress the level of autophagy and promote the macrophages adhesion and migration. These results indicate that high glucose may play an important role in macrophages adhesion and migration through modulating autophagy activities in diabetic nephropathy.

Dendrobium mixture attenuates renal damage in rats with diabetic nephropathy by inhibiting the PI3K/Akt/mTOR pathway

“…Autophagy is considered an important potential mechanism underlying the development of DN; thus, activation of autophagy may be a potential therapeutic target for the treatment of DN (36)(37)(38). Our previous studies confirmed that Beclin-1 and LC3 levels in the kidneys of rats with DN were downregulated, suggesting that autophagy was a self-repairing mechanism of the body to fight against the damage caused by stress (39,40). The results of the present study also indicated that the autophagy activity in the renal tissue of DN was reduced, and that DMix enhanced autophagy and improved renal function.…”

Relationship between lysosomal dyshomeostasis and progression of diabetic kidney disease

“…In an in vitro experiment, adhesion and migration of macrophages increased under HG stimulation. The number of adhesion and migration macrophages further increased when BAFA or CQ were added simultaneously, compared with the HG group 125 . Furthermore, Yuan et al reported that mesenchymal stem cells could elicit M1/M2 macrophages into the M2 phenotype and alleviate renal injury in DKD mice by activating TFEB and subsequently restoring the lysosomal substrate degradation function in macrophages (Fig.…”

“…4 Mechanism of lysosomal dyshomeostasis in macrophages and its effect on renal endothelial cells during DKD. Lysosomal dysfunction promotes adhesion and migration of macrophages 125 . Decreased TFEB activity in macrophages is involved in kidney injury 126 .…”

“… Lysosomal dysfunction promotes adhesion and migration of macrophages 125 . Decreased TFEB activity in macrophages is involved in kidney injury 126 .…”

Comparison analysis of Bacillus Calmette-Guerin induced Autophagy mechanisms in Macrophages Derived from Human Induced Pluripotent Stem Cells and THP-1

“…Macrophages (Mφ) are present in all tissues of mammals. As a key component of the innate immune system, macrophages exhibit extremely signi cant plasticity and play an important role [1][2][3][4] , for example, eliminating invading pathogens, remodeling tissues and clearing dead cells 5 . Macrophages are associated with various types of cancer in terms of tumors [6][7][8][9] , and in the aspect of cardiovascular diseases, atherosclerosis and metabolic regulatory abnormalities are also closely related to it 10,11 .…”