Bone marrow-derived mesenchymal stem cells modulate autophagy in RAW264.7 macrophages via the phosphoinositide 3-kinase/protein kinase B/heme oxygenase-1 signaling pathway under oxygen-glucose deprivation/restoration conditions

Abstract

Background Autophagy of alveolar macrophages is a crucial process in ischemia/reperfusion injury-induced acute lung injury (ALI). Bone marrow-derived mesenchymal stem cells (BM-MSCs) are multipotent cells with the potential for repairing injured sites and regulating autophagy. This study was to investigate the influence of BM-MSCs on autophagy of macrophages in the oxygen-glucose deprivation/restoration (OGD/R) microenvironment and to explore the potential mechanism. Methods We established a co-culture system of macrophages (RAW264.7) with BM-MSCs under OGD/R conditions in vitro. RAW264.7 cells were transfected with recombinant adenovirus (Ad-mCherry-GFP-LC3B) and autophagic status of RAW264.7 cells was observed under a fluorescence microscope. Autophagy-related proteins light chain 3 (LC3)-I, LC3-II, and p62 in RAW264.7 cells were detected by Western blotting. We used microarray expression analysis to identify the differently expressed genes between OGD/R treated macrophages and macrophages co-culture with BM-MSCs. We investigated the gene heme oxygenase-1 ( HO-1 ), which is downstream of the phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) signaling pathway. Results The ratio of LC3-II/LC3-I of OGD/R treated RAW264.7 cells was increased (1.27 ± 0.20 vs. 0.44 ± 0.08, t = 6.67, P < 0.05), while the expression of p62 was decreased (0.77 ± 0.04 vs. 0.95 ± 0.10, t = 2.90, P < 0.05), and PI3K (0.40 ± 0.06 vs. 0.63 ± 0.10, t = 3.42, P < 0.05) and p-Akt/Akt ratio was also decreased (0.39 ± 0.02 vs. 0.58 ± 0.03, t = 9.13, P < 0.05). BM-MSCs reduced the LC3-II/LC3-I ratio of OGD/R treated RAW264.7 cells (0.68 ± 0.14 vs. 1.27 ± 0.20, t = 4.12, P < 0.05), up-regulated p62 expression (1.10 ± 0.20 vs. 0.77 ± 0.04, t = 2.80, P < 0.05), and up-regulated PI3K (0.54 ± 0.05 vs. 0.40 ± 0.06, t = 3.11, P < 0.05) and p-Akt/Akt ratios (0.52 ± 0.05 vs. 0.39 ± 0.02, t = 9.13, P < 0.05). A whole-genome microarray assay screened the differentially expressed gene HO-1 , which is downstream of the PI3K/Akt signaling pathway, and the alteration of HO-1 mRNA and protein expression w...

Electroacupuncture Preconditioning Alleviates Lipopolysaccharides-Induced Acute Lung Injury by Downregulating LC3‐II/I and Beclin 1 Expression

“…Another study inhibition can exacerbate ALI induced by copper oxide nanoparticles (CuONPs) [ 53 ]. Studies have shown that regulated autophagy is a survival mechanism that protects cells from starvation, hypoxia, and infection, while overactivated autophagy can lead to cell apoptosis or necrosis [ 54 ]. Therefore, maintaining a moderate level of autophagy can reduce lung damage and promote cell survival in the body.…”

Progress in preclinical studies of macrophage autophagy in the regulation of ALI/ARDS

“…Therefore, these results indicate that DAMPs released during lung injury can aggravate damage by inducing alveolar macrophage autophagy, promoting the ubiquitination of TRAF6, and activating the downstream MAPK and NF-kB signaling pathways (Figure 4) (128). 4 The modulation of macrophage autophagy is a promising strategy for reducing lung injury Some drugs or interventions such as mesenchymal stem cells (MSCs) and MSCs-derived exosomes can reduce lung injury by regulating macrophage autophagy (153,154). The G proteincoupled receptor cannabinoid receptor 2 agonist HU308 has been shown to enhance macrophage autophagy.…”

“…While moderate autophagy regulation is protective, over-active autophagy can lead to apoptosis or necrosis (160). Wang et al found that oxygen glucose deprivation/restoration conditions resulted in a significant increase in the LC-II/LC-1 ratio and a decrease in p62 expression in alveolar macrophages accompanied by the upregulation of autophagy, while pretreatment with bone marrow mesenchymal stem cells (BMSCs) reduced macrophage autophagy and attenuated the ischemia/reperfusion-induced inflammatory response in ALI mice (153). BM-MSCs could modulate the autophagy of macrophage via thephosphoinositide 3-kinase/protein kinase B (PI3K/Akt) pathway and downstream signaling molecule heme oxygenase-1 (HO-1) (153).…”

“…Some drugs or interventions such as mesenchymal stem cells (MSCs) and MSCs-derived exosomes can reduce lung injury by regulating macrophage autophagy ( 153 , 154 ). The G protein-coupled receptor cannabinoid receptor 2 agonist HU308 has been shown to enhance macrophage autophagy.…”

Extracellular Vesicles Derived from Mesenchymal Stem Cells: A Potential Biodrug for Acute Respiratory Distress Syndrome Treatment

“…These properties make MSCs suitable for ARDS treatment [32]. MSCs have been used to treat lung injury in the preclinical settings [33][34][35][36][37]. Of the 42 registered clinical trials on ARDS treatment, seven have been completed, according to the US National Institutes of Health (https:// clini caltr ials.…”