ABSTRACT
Objective:To evaluate the effect of hydrogen on mitochondrial dynamics in hippocampus of mice with sepsis-associated encephalopathy (SAE).Methods:A total of 224 clean-grade healthy male C57 mice, weighing 20-25g, aged 6-8 weeks, were divided into 4 groups ( n=56 each) using a random number table method: sham operation group (group Sham), sham operation + hydrogen group (group Sham+ H 2), SAE group and SAE + hydrogen group (group SAE+ H 2). Sepsis was produced by cecum ligation and puncture (CLP). Sham+ H 2and SAE+ H 2 groups inhaled 2% hydrogen for 1 h starting from 1 and 6 h after CLP, respectively.The postoperative 7-day survival rate was recorded.Brain tissues were obtained at 24 h after operation for examination of the pathological changes in hippocampal CA1 region (with a light microscope) and for determination of mitochondrial membrane potential (MMP) (by fluorescence spectrophotometry) and ATP content (by a bioluminescence assay) in hippocampal tissues.At 6, 12 and 24 h after operation, hippocampal mitochondria were isolated for determination of the expression of dynamin-related protein 1 (Drp1) and the mitochondrial fusion proteins mitofusin 2 (Mfn2) (by Western blot). Results:Compared with group Sham, the postoperative 7-day survival rate was significantly decreased, the contents of MMP and ATP were decreased, the expression of Drp1 was up-regulated, and the expression of Mfn2 was down-regulated( P<0.05), the pathological changes were aggravated in hippocampal CA1 region in SAE and SAE+ H 2 groups, and no significant change was found in the parameters mentioned above in group Sham+ H 2 ( P>0.05). Compared with group SAE, the postoperative 7-day survival rate was significantly increased, the contents of MMP and ATP were increased, the expression of Drp1 was down-regulated, and the expression of Mfn2 was up-regulated( P<0.05), the pathological changes were attenuated in hippocampal CA1 region in group SAE+ H 2. Conclusion:The mechanism by which hydrogen improves mitochondrial function is probably associated with promoting mitochondrial fusion and inhibiting mitochondrial fission in hippocampus of mice with SAE.
ABSTRACT
Objective:To evaluate the effect of hydrogen on lipopolysaccharide (LPS)-caused inflammatory responses in BV-2 microglia and the role of autophagy.Methods:The BV-2 microglial cells cultured in vitro were seeded in 6- or 96-well plates and were divided into 4 groups ( n=24 each) using a random number table method: control group (group C), group LPS, hydrogen-rich medium group (group H) and autophagy inhibitor 3-methylpurine group (group 3-MA). In group C, cells were cultured in MEM culture medium supplemented with 15% fetal bovine serum for 24 h. In group LPS, LPS was added at a final concentration of 1 μg/ml, and cells were incubated for 24 h. In group H, LPS was added at a final concentration of 1 μg/ml, the culture medium was replaced with a hydrogen-rich medium at a final concentration of 0.6 mmol/L, and cells were incubated for 24 h. In group 3-MA, 3-methylpurine was added at a final concentration of 2 mmol/L, and the subsequent treatment was similar to those previously described in group H. The cell survival rate was detected by CCK-8 assay.The concentrations of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-10 and transforming growth factor-β (TGF-β) in supernatant were detected by enzyme-linked immunosorbent assay.The percentage of ionized calcium binding adaptor molecule-1 (Iba-1) +, Iba-1 + CD86 + and Iba-1 + CD206 + cells was detected by flow cytometry.The expression of microtubule-associated protein 1 light chain 3 Ⅰ (LC3 Ⅰ), LC3Ⅱ, Beclin-1 and p62 was detected by Western blot, and the ratio of LC3Ⅱ/LC3Ⅰ was calculated. Results:There was no significant difference in the cell survival rate among the four groups ( P>0.05). Compared with group C, the concentrations of TNF-α, IL-6, IL-10 and TGF-β and percentage of Iba-1 +, Iba-1 + CD86 + and Iba-1 + CD206 + cells were significantly increased in LPS, H and 3-MA groups, the LC3Ⅱ/LC3Ⅰ ratio and Beclin-1 expression was significantly down-regulated, and p62 expression was up-regulated in LPS and 3-MA groups, and the ratio of LC3LC3Ⅱ/LC3Ⅰ and Beclin-1 expression was significantly up-regulated, and p62 expression was down-regulated in group H ( P<0.05). Compared with group LPS, the concentrations of TNF-α and IL-6 were significantly decreased, the concentrations of IL-10 and TGF-β were increased, the percentage of Iba-1 + and Iba-1 + CD86 + cells were decreased, the percentage of Iba-1 + CD206 + cells was increased, the LC3Ⅱ/LC3Ⅰ ratio and Beclin-1 expression was up-regulated, and p62 expression was down-regulated in group H ( P<0.05), and no significant change was found in the above indexes in group 3-MA ( P>0.05). Compared with group H, the concentrations of TNF-α and IL-6 were significantly increased, the concentrations of IL-10 and TGF-β were decreased, the percentage of Iba-1 + and Iba-1 + CD86 + cells was increased, the percentage of Iba-1 + CD206 + cells was decreased, the LC3Ⅱ/LC3Ⅰ ratio and Beclin-1 expression was down-regulated, and p62 expression was up-regulated in group 3-MA ( P<0.05). Conclusion:The mechanism by which hydrogen reduces LPS-caused inflammatory responses in BV-2 microglia is related to enhancing autophagy and inhibiting microglial activation.
ABSTRACT
Objective@#To evaluate the effect of hydrogen on mitochondrial biosynthesis in the hippocampus of mice with sepsis-associated encephalopathy (SAE).@*Method@#Two hundred and twenty-four healthy clean-grade male C57BL/6J mice, aged 6-8 weeks, weighing 20-25 g, were divided into 4 groups (n=56 each) using a random number table method: sham operation group (group SH), sham operation plus hydrogen group (group SH+ H2), group SAE, and SAE plus hydrogen group (group SAE+ H2). The model of SAE was established by cecal ligation and puncture in anesthetized mice.Group SH+ H2 and group SAE+ H2 inhaled 2% hydrogen for 1 h starting from 1 and 6 h after operation, respectively.Twenty mice were selectde to record the postoperative 7-day survival rate.The remaining animals were sacrificed at 24 h after operation, and brain tissues were taken for examination of the pathological changes in hippocampal CA1 region (with a light microscope) and for determination of neuronal apoptosis (by TUNEL), mitochondrial membrane potential (MMP) (by fluorescence spectrophotometry) and ATP content (by a bioluminescence assay). The apoptosis rate was calculated.The expression of peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) in hippocampus was determined by Western blot at 6, 12 and 24 h after operation.@*Results@#Compared with group SH, the postoperative 7-day survival rate was significantly decreased, the apoptosis rate of hippocampal neurons was increased, the contents of MMP and ATP were decreased, and the expression of PGC-1α was up-regulated in SAE and SAE+ H2groups (P<0.05), and no significant change was found in the parameters mentioned above in group SH+ H2(P>0.05). Compared with group SAE, the postoperative 7-day survival rate was significantly increased, and the apoptosis rate of hippocampal neurons was decreased, the contents of MMP and ATP were increased, and the expression of PGC-1α was up-regulated (P<0.05), and the pathological changes of hippocampal tissues were significantly attenuated in group SAE+ H2.@*Conclusion@#The mechanism by which hydrogen mitigates SAE may be related to promoting mitochondrial biosynthesis in mice.
ABSTRACT
Objective To evaluate the effect of hydrogen on mitochondrial biosynthesis in the hippocampus of mice with sepsis-associated encephalopathy (SAE).Method Two hundred and twenty-four healthy clean-grade male C57BL/6J mice,aged 6-8 weeks,weighing 20-25 g,were divided into 4 groups (n=56 each) using a random number table method:sham operation group (group SH),sham operation plus hydrogen group (group SH+H2),group SAE,and SAE plus hydrogen group (group SAE+H2).The model of SAE was established by cecal ligation and puncture in anesthetized mice.Group SH+H2 and group SAE+H2 inhaled 2％ hydrogen for 1 h starting from 1 and 6 h after operation,respectively.Twenty mice were selectde to record the postoperative 7-day survival rate.The remaining animals were sacrificed at 24 h after operation,and brain tissues were taken for examination of the pathological changes in hippocampal CA1 region (with a light microscope) and for determination of neuronal apoptosis (by TUNEL),mitochondrial membrane potential (MMP) (by fluorescence spectrophotometry) and ATP content (by a bioluminescence assay).The apoptosis rate was calculated.The expression of peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) in hippocampus was determined by Western blot at 6,12 and 24 h after operation.Results Compared with group SH,the postoperative 7-day survival rate was significantly decreased,the apoptosis rate of hippocampal neurons was increased,the contents of MMP and ATP were decreased,and the expression of PGC-1α was up-regulated in SAE and SAE+H2groups (P＜0.05),and no significant change was found in the parameters mentioned above in group SH+H2 (P＞0.05).Compared with group SAE,the postoperative 7-day survival rate was significantly increased,and the apoptosis rate of hippocampal neurons was decreased,the contents of MMP and ATP were increased,and the expression of PGC-1α was up-regulated (P＜0.05),and the pathological changes of hippocampal tissues were significantly attenuated in group SAE+H2.Conclusion The mechanism by which hydrogen mitigates SAE may be related to promoting mitochondrial biosynthesis in mice.