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ObjectiveTo investigate the effects of Lactobacillus rhamnosus GG （LGG）on microglia and Tau phosphorylation in the hippocampus of aged mice induced by anesthesia and surgery. MethodsA total of thirty 18-month-old C57BL/6J mice were randomly divided into three groups： control group， anesthesia surgery group， and anesthesia surgery + LGG group （10 mice/group）. The aged mice were oral administered by NS or LGG 109 CFU 150 μL once a day for 20 days. Then anesthesia surgery group and anesthesia surgery +LGG group received anesthesia with isoflurane and exploratory laparotomy. The activation status of microglia in the hippocampus was detected by immunofluorescence staining 12 hours after surgery. IL-6 concentration changes was detected by ELISA. The expression changes of Tau protein phosphorylation site （Tau-pS202/pT205） and total Tau protein was detected by western blot. ResultsThe microglia in the hippocampus of the control group were in a resting state， and the concentration of inflammatory factor IL-6 was （82.08 ± 12.07） pg/mL in control group. Compared to the control group， the anesthesia surgery group showed microglial cell Microglia were activated， the concentration of inflammatory factors IL-6 increased significantly to （123.7±5.72） pg/mL （P=0.000）， and the expression of phosphorylated Tau-pS202/pT205 increased the hippocampus （P=0.002）. Compared to the anesthesia surgery group， the activated microglia were inhibited， the concentration of IL-6 decreased to （96.68±9.59） pg/mL （P=0.008）， and the expression of phosphorylated Tau-pS202/pT205 reduced significantly in the AS+LGG group （P=0.002）. While there were no significant changes in total Tau protein among 3 groups. ConclusionPreoperative administration of probiotic LGG can alleviate the activation of microglia， increased secretion of inflammatory factors， and increased Tau protein phosphorylation levels in the hippocampus of elderly mice caused by anesthesia surgery.
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AIM: To explore the effects of prolonged sevoflurane exposure on prefrontal cortical metabolites in aged mice using a metabolomics approach. METHODS: Ten 18-month-old male C57BL/J6 mice were divided into a sevoflurane group (Sev group) and a control group (Con group) by the random number table method, with five mice in each group. Mice in the sevoflurane group were anesthetized with 3% sevoflurane and 60% oxygen for 6 h. Mice in the control group were given 60% oxygen under the same conditions for 6 h. All mice were executed immediately after the end of anesthesia or oxygenation, and fresh prefrontal cortex was taken for LC-MS/MS analysis. The data obtained were processed and analyzed using OSV2.1 software (AB SCIEX). RESULTS: Compared with the control group, the content of glutathione, arginine, coenzyme A, 1-methyl-histi-dine, L-arginino-succinate and 2-isopropylmalic acid was reduced in the prefrontal cortex of aged mice in the sevoflurane group, while the content of mesaconic acid was increased. A total of 29 metabolic pathways were involved in the differential metabolites, with significant enrichment in nine pathways including arginine biosynthesis. CONCLUSION: Significant changes in metabolites such as glutathione, arginine, and coenzyme A occurred in the prefrontal cortex of aged mice exposed to prolonged sevoflurane. The changes in these products may affect the amino acid metabolic pathway and the gluconeogenic pathway.
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Objective:To explore the improvement and its mechanism of minocycline on sevoflurane anesthesia induced cognitive dysfunction in aged mice.Methods:Totally 75 aged clean-grade C57BL/6 mice were randomly divided into control (Con) group( n=25), sevoflurane (Sev) group( n=25) and sevoflurane + minocycline (Sev+ Min) group( n=25). Anesthetic injury was induced by 3% sevoflurane (2 h/d for 3 days) in Sev group. Minocycline (50 mg/kg) was injected intraperitoneally first, and then 3% sevoflurane (2 h/d for 3 days) anesthesia was performed in Sev+ Min group. Saline alone was injected intraperitoneally (once a day for 3 days) in Con group.The spatial memory function was detected by Morris water maze experiments. BrdU was used to label new neuron and the proliferation was observed by immunohistochemistry. The field excitatory postsynaptic potential (fEPSP) slope was measured in hippocampal dentate gyrus (DG) region of isolated brain slices by electricphysiological technique.The data were analyzed by repeated measures analysis of variance and SNK-q test using SPSS 21.0 software. Results:Results from positioning navigation experiment showed that the group×time interaction effect of mice was significant( F=15.65, P<0.01). On the 6th day after anesthesia, compared with Con group, the escape latency of the original platform in Sev group was significantly increased ( q=4.35, P<0.05) in space exploration experiment, while the target quadrant time ratio ( q=6.15, P<0.05))and the mean annulus crossings ( q=6.45, P<0.05) were significantly decreased. Compared with Sev group, the escape latency in Sev+ Min group was significantly decreased ( q=3.01, P<0.05), while the target quadrant time ratio ( q=3.21, P<0.05) and the mean annulus crossings ( q=3.48, P<0.05) were significantly increased. In immunohistochemistry experiment, the number of BrdU positive cells in Sev group was significantly reduced ((227.45±43.25), q=8.67, P<0.01) compared with Con group (355.87±62.58). Compared with Sev group, the number of BrdU positive cells in Sev+ Min group was significantly increased ((338.73±47.27), q=8.68, P<0.01). In electricphysiological test, the fEPSP slope after high frequency stimulation in Sev group ((126.83±25.67)%, q=6.18, P<0.01)) was significantly lower than that in Con group((214.38±43.42)%). In Sev+ Min group, the fEPSP slope was significantly higher ((178.49±32.67)%, q=3.64, P<0.05) than that in Sev group. Conclusion:Sevoflurane anesthesia can induce the short-term cognitive dysfunction in aged mice, and its mechanism is related to inhibiting neuron proliferation and synaptic plasticity. Minocycline can alleviate the damage caused by sevoflurane.
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Background: Melatonin is one of the free radical inhibitors, antioxidants, and anti-apoptosis, which contributes to improving the growth of egg. Accordingly, in the present study explores the possible effects of melatonin on the autophagy pathway of mature oocytes in vitro in adult rats. Methods: In this study, we collected GV oocytes of six months and six to eight weeks old mice and cultured to MII stage for 12 h and 24h in IVM culture media with and without melatonin (10 μM). Then we assessed the expression of SIRT1 and LC3 by RT-PCR and immunostaining test. Results: The expression of SIRT1 and LC3in Old +Melatonin compared to an Old group was significantly increased [(43.2% vs 11.6%, P<0.01) (24.3% vs 10.1%, P<0.01)] respectively. Conclusion: Given the role of Sirt1 and LC3 in increasing cell resistance to stress, melatonin could increase Sirt1 and LC3 expression in oocytes a time-dependent manner and prevent cellular autophagy.
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Objective@#To evaluate the immunogenicity of split influenza H1N1 vaccine formulated with an oil-in-water nano-emulsion adjuvant in aged mice and young mice.@*Methods@#A nano-emulsion adjuvant formulated split influenza H1N1 vaccine was used to immunize aged and young mice through intramuscular injection. Each mouse was immunized with 0.012 μg of hemagglutinin (HA) twice with an interval of 28 d. Hemagglutination inhibition (HI) titers in serum were measured 27 d after first immunization. Serum HI, IgG1 and IgG2a titers were detected 14 d after the last immunization. No adjuvant-formulated vaccine and normal saline (NS) were used to set up control groups. Virus challenge test was carried out using 10 times the median lethal dose (LD50) of A/Puerto Rico/8/34 (H1N1) strain two weeks after the last immunization and the protective effects were assessed through measuring the dynamic changes in body weight and survival rate.@*Results@#Higher levels of serum HI, IgG1 and IgG2a antibodies and higher HI antibody conversion rates were induced in the adjuvant groups, especially in the aged mice group, than in the control groups. Nano-emulsion adjuvant improved the immunogenicity of HA and mouse immunity to A/Puerto Rico/8/34 (H1N1).@*Conclusions@#Nano-emulsion adjuvant could enhance the immunogenicity of influenza antigens, especially in aged mice.
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Objective To study the effects of diterpene ginkgolides meglumine injection ( DGMI) on memory impairment, activation of microglia and astrocytes and inflammatory cytokines in aged mice. Methods Twenty aged mice (22 months old) were randomly divided into two groups:aged mouse group(n=10) and DGMI group(n=10). Another 10 mice (2 months old) were selected as young mouse control group. The mice in DGMI group were received 5 mg/kg DGMI per day by tail vain injection for 4 weeks. The mice in the other two groups were received the same amount normal saline for 4 weeks. The Morris water maze was used to evaluate the function of spacial learning and memory after administration of drugs. The ex-pression of CD11b,GFAP,IL-1β,IL-6,TNF-α and NFκB in mice brain hippocampus were detected by West-ern blot. Results (1) The escape latency time of aged mouse group was significantly longer than that of young mouse control group from the 2nd day to the 7th day(P<0. 01). The times of platform crossing,time and distance in target quadrant of aged mouse group were significantly shorter than those of young mouse group (all P<0. 01). Compared with aged mouse group,DGMI significantly reduced the escape latency time of DGMI group (P<0. 01). DGMI increased the times of platform crossing,time and distance in target quad-rant of aged mouse group (P<0. 01). (2) The expressions of CD11b,GFAP in young mouse control group, aged mouse group and DGMI group were as follows respectively:CD11b:(1. 036±0. 023),(1. 757±0. 046), (1. 214±0. 024);GFAP:(1. 022±0. 071),(1. 344±0. 021),(1. 086±0. 073). DGMI reduced the expres-sion of CD11b and GFAP in hippocampus compared with aged mouse group ( t=5. 556,P<0. 01;t=5. 484, P<0. 01). (3) The expressions of IL-1β,IL-6,TNF-α and NFκB in young mouse control group,aged mouse group and DGMI group were as follows respectively:IL-1β:( 1. 003 ± 0. 057),( 2. 062± 0. 105),( 1. 182± 0. 084);IL-6:(1. 018±0. 024),(1. 583± 0. 052),( 1. 152± 0. 031); TNF-α:( 1. 021± 0. 054),(1. 449± 0. 053),(1. 211±0. 036);p-NFκB:(1. 052±0. 034),(1. 782± 0. 113),( 1. 158± 0. 066). DGMI reduced the expression of p-NFκB(t=6. 547,P<0. 01) and pro-inflammatory cytokines including IL-1β(t=8. 513,P<0. 01),IL-6(t=3. 421,P<0. 01) and TNF-α( t=5. 562,P<0. 01) in hippocampus compared with aged mouse group. Conclusion DGMI can improve the ability of learning and memory in aged mice. The mecha-nism may be related with inhibiting activity of microgliosis,astrocytosis,NFκB and neuroinflammaton.
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Objective@#To investigate whether the artermisinin has beneficial efficacy to improve the learning and memory in aged mice, as well as the possible mechanisms regarding the inflammatory cytokines and monoamlne neurotransmitters.@*Methods@#30 aged mice(22 month old) were randomly divided into the aged mouse model control group(n=10), the artemisinin low dose group(artemisinin 0.1% in feed, n=10)and the artemisinin high dose group(artemisinin 0.3% in feed, n=10). Another 10 mice(2 month old) served as young mouse model control group. The artemisinin low dose group and the artemisinin high dose group fed artemisinin feed for 10 weeks. The aged mouse model control group and the young mouse model control group were fed standard feed.Morris water maze test was performed to assess learning and memory capacities for evaluation of the cognitive degree. Serum TNF-α and IL-6 were also detected by ELISA and dopamine, norepinephrine, serotonin in the brain were analyzed by HPLC.@*Results@#(1) Morris water maze test showed, the retention time of the aged mouse model control group was significantly longer than that of the young mouse model control group (P<0.05). The retention time of the artemisinin low dose group and the artemisinin high dose group was significantly shorter than that of the aged mouse model control group (P<0.05). In the ninth days of the reverse recessive platform experiment, the retention time of the artemisinin low dose group ((50.1±19.9) s) and the artemisinin high dose group ((43.2±17.6) s) was significantly shorter than that of the aged mouse model control group ((66.1±29.1)s, P<0.05). (2) Serum inflammatory factors test showed, the level of IL-6 and TNF-αin the artemisinin low dose group (IL-6 : (28.4±4.3) pg/ml, TNF-α: (51.8±8.2) pg/ml) and the artemisinin high dose group(IL-6 : (17.6±2.3) pg/ml, TNF-α: (38.6±12.5) pg/ml) were significantly lower than those in aged mouse model control group(IL-6 : (36.12±7.98)pg/ml), TNF-α : (67.32±10.27) pg/ml, P<0.05). (3) Neurotransmitter content test in the brain showed, the content of DA((19.96±3.89) mmol/ml) and 5-HT((5.73±0.93)mmol/ml) in low dose artemisinin group was higher than that in aged mouth model control group. The content of DA((26.13±5.66) mmol/ml), NE((16.31±2.69) mmol/ml) and 5-HT((8.03±1.93) mmol/ml) in high dose artemisinin group was higher than that in aged mouth model group(DA(13.96±3.89) mmol/ml, NE(8.73±2.16) mmol/ml, 5-HT (3.82±1.09)mmol/ml, all P<0.05).@*Conclusion@#Artemisinin can improve the ability of learning and memory in aged mice. The mechanism may be related to inhibiting the inflammation and promoting the level of neurotransmitters in the brain of aged mice.
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Objective To observe the changes of hippocampal NogoA-NgR1 signaling on postoperative cognitive function (POCD) in aged mice, and explore the potential underling mechanism.Methods Isoflurane anesthesia and laparotomy were applied to establish the POCD model.Forty aged male C57BL/6 mice were randomly divided into the following four groups (n=10): group O2+saline (group OS), group O2+NEP1-40 (group ON), group isoflurane anesthesia+laparotomy surgery+saline (group SS), and group isoflurane anesthesia+laparotomy surgery+NEP1-40 (group SN).Cannula placement was performed into lateral ventricle 7 days before the surgery.Animals were subjected to an administration of NEP1-40 (20 μg/2 μl) or isochoric saline via intracerebroventricular injection once daily for 8 consecutive days, injection was given from 2 h before isoflurane anesthesia to the last behavioral test.Open field test was performed at 5th d after operation.Contextual and cued fear conditioning training and testing were exhibited at 6th and 7th d after operation, respectively.The hippocampus was harvested 2 h after the behavioral test.Western blot was used to detect the expressions of NogoA, NgR1, RhoA, ROCK2 and GAP43.Golgi staining was applied to measure the changes of dendritic spines in hippocampal CA1 area.Results Compared with the groups OS and ON, the freezing time in the contextual fear conditioning test was significantly decreased, the contents of NogoA, NgR1, RhoA and ROCK2 were significantly increased, the content of GAP43 and the number of dendritic spine were significantly decreased in group SS (P<0.05).Compared with the group SS, the freezing time in the contextual fear conditioning test was significantly increased, the contents of RhoA and ROCK2 were significantly decreased, the content of GAP43 and the number of dendritic spine were significantly increased in group SN (P<0.05).Conclusion Over-activated of hippocampal NogoA-NgR1 signaling participated in the pathogenesis of POCD in aged mice.
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Objective To study the effects of drug-containing serum of Ficus Hirta on oxidative damage of spleen lymphocyte due to aging in aged mice; To discuss its mechanism of action.Methods Forty aged mice were randomly divided into control group and high-, medium- and low-dose Ficus Hirta groups. Control group was given 0.9% sodium chloride solution for gavage, while high-, medium- and low-dose Ficus Hirta groups were given 6.6, 4.4, and 2.2 g/kg aqueous extract of Ficus Hirta for gavage. The spleen index was observed for optimum dose in aged mice. The optimum time and dilution of drug-containing serum of Ficus Hirta were confirmed by MTT method in lymphocyte proliferation test. The positive rate of senescent cells, the activity of T-SOD and the contents of MDA and ROS were determined in cellular antioxidant experiment after treated by optimal drug-containing serum for 48 h. Results Compared with the control group, the spleen index was significantly improved in high-, medium- and low-dose Ficus Hirta groups (P<0.05,P<0.01). 20% drug-containing serum of Ficus Hirta cultivated for 48 h had the best effects on lymphocyte proliferation in aged mice. 20% drug-containing serum of Ficus Hirta could significantly decrease the positive rate of senescent cells (P<0.01), improve T-SOD activity and decrease the contents of MDA and ROS (P<0.05,P<0.01).Conclusion The drug-containing serum of Ficus Hirta can improve the proliferative activity of spleen lymphocyte in aged mice and the mechanism of action may be involved in decreasing the positive rate of senescent cells and increasing antioxidant ability of lymphocyte.
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OBJECTIVE:To study the effects of simvastatin on oxidative stress and cell apoptosis in aged mice with myocardi-al ischemia-reperfusion (IR). METHODS:Aged mice were randomly divided into sham operation group (phosphate buffer solu-tion),model group(phosphate buffer solution)and simvastatin low-dose,medium-dose and high-dose groups(2.5,5 and 20 mg/kg) with 14 mice in each group. Those groups were given relevant medicine intraperitoneally before modeling for 7 d,once a day. IR model was induced in those groups except for sham operation group. The area ratio of myocardial infarction,myocardial cell apop-tosis rate,activity of myocardial tissue apoptosis gene Caspase-3,the protein expression of Bax and Bcl-2,Akt phosphorylation, serum concent of MDA and activity of SOD were all detected. RESULTS:Compared with sham operation group,the area ratio of myocardial infarction,myocardial cell apoptosis rate,Caspase-3 activity,the protein expression of Bax and MDA content were all increased in model group,while the protein expression of Bcl-2,Akt phosphorylation and SOD activity were decreased(P0.05). CONCLUSIONS:Simvastatin can relieve myocardial IR injury in aged mice,and the mechanism of which may be associated with inhibiting myocardial cell apoptosis and the generation of oxidative stress.
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Aim To investigate the protective effect of flavonoids from Radix tetrastigmae (RTFs)on lipopo-lysaccharide (LPS)induced acute lung injury (ALI) of aged mice and the mechanism.Methods Aged C57BL/6J mice were bronchially instillated LPS to in-duce ALI.RTFs were orally administered to treat ALI. After 3 days,bronchoalveolar lavage fluid (BALF) was collected to enumerate leukocytes with Wright-Gi-emsa staining,and to detect inflammatory cytokines with ELISA.ELISA and Western blot methods were al-so used to detect the expression of MAPKs and NF-κB in lung tissues.The activity of NF-κB in nucleic pro-tein extract was detected with TransAMkit.Results ALI models were successfully induced through LPS in-stillation.RTFs significantly reduced leukocyte,espe-cially neutrophil infiltration in BALF,inhibited IL-1 β, IL-6,IL-1 2p40,TNF-αand sTNF-R1 secretion,and improved pathohistological change of lung tissues.Be-sides,RTFs significantly attenuated the phosphoryla-tion of p38MAPK,NF-κB and the activity of NF-κB. Conclusion RTFs inhibits LPS-induced ALI through p38MAPK and NF-κB pathway and exhibits significant anti-inflammation effect on aged mice.
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Objective To explore the immunomodulatory effects of seaweed polysaccharide(PSS)in aged mice induced by D-ga-lactose (D-gal).Methods D-gal was injected intraperitoneally to establish the aged mice model,meanwhile the aged mice was intra-gastricly administrated by PSS.Peritoneal macrophages were collected,and macrophage secretion of nitric oxide (NO),nitric oxide synthase (NOS)levels and expression levels of inducible nitric oxide synthase (iNOS)mRNA were detected.The spleen indexs of the agd mice were calculated,and effects of PSS on spleen microscopic structure of mouse were observed.The changes of spleen cell cycle in aged model mice were detected by flow cytometry assay.Results PSS could enhance macrophage synthesis of NO and NOS of the aged mice and up-regulate the expression of iNOS mRNA levels.And the spleen index of the aged mice increased obviously, the hyperplasia of spleen capsule was obvious.Moreover,PSS could increase the percentage of S phase and G2/M phase cells of the aged mice spleen.Conclusion PSS could enhance the immune function of aged mice induced by D-gal,which is worthy of further study,which development.
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Objective To explore the relationship between trace elements proportion in food and health. Methods 45 mice aged 12 month were randomly divided into 3 groups: control group(n=16) and two experimental groups(n=15).The mice in the experimental groups were given Zn, Li, Fe, Se, Mn, Cu, Co in different proportion by food for 60 days, then all mice were sacrificed, thymus weight, spleen weight, thymus coefficient, spleen coefficient, bone indexes were determined. Results Supplementation of the trace elements in food increased the content of Ca2+ in the bone of the aged mice and proportion variety of trace elements might induce the changes of thymus weight, spleen weight, spleen coefficient and bone indexes. Conclusion The reasonable proportion of trace elements in food could increase the content of bone Ca2+ in aged mice.
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Objective:To investigate the role of platelet-derived growth factor(PDGF)-AB on angiogenensis in aged mice.Methods:Cardiac microvascular endothelial cells(CMEC)from the hearts of young adult and old mice were cultured.Expression of PDGF-BB and PDGF-AA was detected by RT-PCR.The migration of CMEC was determined with ChemoTX Chamber.Ear angiogenesis model was made in mice.Blood flow in neo-microvessels and collateral vessels was measured with Laser Doppler.Then biotin-labeled Dextran-lysine was injected into the mice through cardiac puncture to label vessels.Ears were cut and immunohistochemistry was carried out by ABC method.Results:Both PDGF-BB and PDGF-AA were highly ex-pressed in CMEC of young adult mice;expression of PDGF-BB was not detected in aged mice.PDGF-AB reverted the levels of PDGF-BB in aged CMEC to the levels of young adult mice.Migration rate of CMEC in aged mice was significantly increased after stimulation by PDGF-AB(P