Sevoflurane blocks KLF5-mediated transcriptional activation of ITGB2 to inhibit macrophage infiltration in hepatic ischemia/reperfusion injury.

BACKGROUND: Sevoflurane (Sevo) preconditioning and postconditioning play a protective role against injury induced by hepatic ischemia/reperfusion (I/R). At the same time, the involvement of macrophage infiltration in this process and the precise mechanisms are unclear. Here, we designed this research to elucidate the protective effects of Sevo against hepatic I/R injury and the molecules involved. METHODS: The alleviating effect of Sevo on the liver injury was analyzed by liver function analysis, hematoxylin and eosin staining, Masson trichrome staining, terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end labeling, western blot analysis and an enzyme-linked immunosorbent assay. An in vitro cell model was developed using alpha mouse liver 12 (AML12) cells, and the cell model was treated with oxygen-glucose deprivation and reoxygenation and Sevo. Multiple bioinformatics databases were used to screen transcriptional regulators related to hepatic I/R injury and the targets of Krueppel-like factor 5 (KLF5). KLF5 expression was artificially upregulated alone or with integrin beta-2 (ITGB2) knockdown to substantiate their involvement in Sevo-mediated hepatoprotection. RESULTS: Sevo protected the liver against I/R injury by reducing cell apoptosis and inflammatory response. KLF5 was upregulated in liver tissues following I/R injury, whereas KLF5 overexpression aggravated macrophage infiltration and liver injury induced by I/R injury. KLF5 bound to the promoter of ITGB2 to enhance ITGB2 transcription. Knockdown of ITGB2 reversed the aggravation of injury caused by KLF5 overexpression in mice and AML12 cells. CONCLUSIONS: Sevo blocked KLF5-mediated transcriptional activation of ITGB2, thereby inhibiting macrophage infiltration in hepatic I/R injury.

Sevoflurane Preconditioning Downregulates GRIA1 Expression to Attenuate Cerebral Ischemia-Reperfusion-Induced Neuronal Injury.

Cerebral ischemia/reperfusion (I/R) injury is the main cause of death following trauma. The neuroprotective effect of sevoflurane (Sev) has been implicated in cerebral I/R injury. However, the mechanisms remain elusive. In this study, we aimed to explore its function in PC12 exposed to oxygen-glucose deprivation/reoxygenation (OGD/R) and in rats challenged with I/R. Sev pretreatment reduced the damage of PC12 cells after OGD/R treatment. Moreover, Sev pretreatment ameliorated neurobehavioral deficits induced by I/R treatment, reduced brain infarct volume, and decreased apoptosis of neurons in hippocampal tissues. Sev pretreatment reduced the surface expression of glutamate receptor 1 (GRIA1) in neurons, while GRIA1 reduced the neuroprotective effects of Sev pretreatment in vitro and in vivo. There was no difference in the surface expression of GRIA2 in rats with I/R and PC12 cells exposed to OGD/R. The ratio of GRIA1/GRIA2 surface expression was reduced, and calcium permeable-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (CP-AMPAR) was blocked by Sev. Together, Sev might exert beneficial effects on cerebral I/R-induced neuronal injury through inhibiting the surface expression of GRIA1 and blocking CP-AMPAR.

[Intervention effects and mechanism of Chinese herbal medicine of supplementing Qi and activating blood circulation on chronic intermittent hypoxia composite insulin resistance ApoE~(-/-) mice model].

This study aims to observe the intervention effects of Chinese herbal medicine of supplementing Qi and activating blood circulation on chronic intermittent hypoxia(CIH) composite insulin resistance(IR) mediated atherosclerosis(AS) mice model,and to observe the mechanism of SREBP-1 c signaling molecule.IR Apo E-/-mice model was induced by high-fat diet combined with STZ injection.Then the mice were treated with hypoxic animal incubator for 8 h per day and 8 weeks to establish a CIH+IR-ApoE-/-mouse model.Model mice were randomly and averagely divided into normoxic control group(NC),model group(CIH) and SREBPs inhibitor group(betulin),atorvastatin group(WM),TCM low-dose group(TCM-L),TCM middle-dose group(TCM-M) and TCM high-dose group(TCM-H) group.Chinese herbal medicine of supplementing Qi and activating blood circulation including ginsenosides combined with ligustrazine(TMP) were used as intervention drugs.The study observed the effect of drugs on IR,serum lipid,inflammation,stress,AS and SREBP-1 c related molecules.The results showed that fasting blood glucose in TCM-H group decreased compared with other experimental groups(P<0.05).HDL-C level in betulin group,WM group,TCM-H group was higher than that in CIH group(P<0.05).LDL-C level in TCM-M group,TCM-H group is lower than that in CIH group(P<0.05).The level of CRP in CIH group was higher than that in other groups(P<0.05).The level of SOD in TCM-H group was higher than that in CIH group(P<0.05).NC group and CIH group showed obvious AS aortic plaque,while betulin group,WM group,TCM-H group showed reduction in AS plaque(P<0.05).For descending aorta,AS plaque in CIH group was multiple and large,while less and smaller in WM group and TCM-H(P<0.05).The expression of SREBP-1 c and FAS in aorta and skeletal muscle in TCM-H group was lower than that in CIH group(P<0.05).In aorta,the expression of TNF-α and CD106(VCAM-1) was lower in TCM-H group than that in CIH group(P<0.05).In aorta,skeletal muscle and liver,the level of p-IRS-1 in TCM-H group was significantly higher than that in CIH group(P<0.05).In aorta and liver,the expression of HIF-1α in TCM-H group was lower than that in CIH group(P<0.05).The study demonstrated that combination ginsenosides with TMP could improve IR and serum lipid level and inhibit inflammation and oxidative stress as well as ultimately alleviate AS to some extent.And the mechanism of its interventional effects might be related to the inhibition of CIH-induced upregulation of SREBP-1 c related molecules.

Intermittent Hypoxia Composite Abnormal Glucose Metabolism-Mediated Atherosclerosis In Vitro and In Vivo: The Role of SREBP-1.

OBJECTIVE: The aim of this study was to establish a 3T3-L1 adipocyte model and ApoE-/- mouse model of intermittent hypoxia (IH) composite abnormal glucose metabolism (AGM) in vitro and in vivo and explore their synergistic damage effect leading to atherosclerosis (AS) and the influence of SREBP-1 signaling molecule-related mechanisms. METHODS: Mature 3T3-L1 adipocytes were cultured with complete culture medium containing DEX 1 × 106 mol/L for 96 h to establish an AGM-3T3-L1 adipocyte model. Then, AGM-3T3-L1 adipocytes were treated with IH for 0 cycles, 2 cycles, 4 cycles, 8 cycles, 16 cycles, and 32 cycles and sustained hypoxia (SH). ApoE-/- mice were treated with high-fat diet and injection of STZ solution to establish an AGM-ApoE-/- mouse model. A total of 16 AGM-ApoE-/- mice were randomly and averagely divided into the normoxic control group (NC) and model group (CIH). AGM-ApoE-/- mice of the CIH group were treated with IH, which meant that the oxygen concentration fell to 10 ± 0.5% in the first 90 seconds of one cycle and then increased to 21 ± 0.5% in the later 90 seconds, continuous for eight hours per day (09 : 00-17 : 00) with a total of eight weeks. Eight C57BL/6J mice were used as the blank control group (Con) which was fed with conventional diet. qPCR and Western blotting were used to detect the expression level of SREBP-1c, FAS, and IRS-1. Oil Red O staining was used to compare the plaque of the aorta among each mouse group. RESULTS: As a result, within 32 cycles of IH, mRNA and protein expression levels of SREBP-1c and FAS in AGM-3T3-L1 adipocytes were elevated with the increase in IH cycles; the mRNA expression of IRS-1 was decreased after IH 32 cycles and lower than that of the SH group. For the study in vivo, Oil Red O staining showed a more obvious AS aortic plaque in the CIH group. After CIH treatment of 4 w and 8 w, fasting blood glucose (FBG) of the NC group and CIH group was higher than that of the Con group, and the insulin level of the CIH group was higher than that of the Con group after IH treatment of 8 w. The expressions of the IRS-1 mRNA level in the aorta, skeletal muscle, and liver of the CIH group were lower than those in the Con group. The mRNA and protein expression of SREBP-1c and its downstream molecule FAS in the aorta, skeletal muscle, and liver significantly enhanced in the CIH group in contrast with those in the Con group. CONCLUSION: The CIH composite AGM could promote the progress of AS, which might be related to the modulation of the expression of SREBP-1-related molecular pathways.

[Effect of Chinese medicine of nourishing kidney and clearing liver on intermittent hypoxia induced injury model of HUVECs through p38MAPK/NF-κB signaling pathway].

This study aims to explore the intervention effect of Chinese medicine of nourishing kidney and clearing liver on intermittent hypoxia(IH) induced injury model of HUVECs through p38MAPK/NF-κB signaling pathway in vitro. HUVECs injury model was induced by modified IH treatment. The effective components of Chinese medicine of nourishing kidney and clearing liver including isochteroside, aucubin and ligustrazine were used as intervention drugs. The optimal compatibility concentration of them was screened in vitro, and then the optimal compatibility concentration was selected as the intervention dose to observe the effect on p38MAPK/NF-κB signaling pathway in IH induced injury model of HUVECs. The results showed that isochnae, aucubin and ligustrazine had the best anti-inflammatory effect at concentration of 0.01 mg•L-1. NF-κB p65 and p-IκB in the nucleus in IH group were significantly higher than those in the normal control(N) group and the other groups. Immunofluorescence staining showed significant translocation of NF-κB p65 nucleus in IH group, and HUVECs adhesion capacity in IH group was increased significantly. As compared with IH group, the expression levels of p-p38MAPK, NF-κB p65 and p-IκB in p38MAPK inhibitor(INH) group and Chinese medicine of nourishing kidney and clearing liver(GDC) group were significantly decreased, and HUVECs adhesion capacity in INH group and GDC group was significantly inhibited as well. The optimal concentration of Chinese medicine of nourishing kidney and clearing liver can inhibit the phosphorylation of p38MAPK, and then inhibit the nuclear translocation and transcription function of NF-κB. This may be the mechanism of the protective effect of Chinese medicine on IH induced injury model of HUVECs.