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The intestinal epithelial barrier has evolved to maintain a delicate balance between absorb-ing essential nutrients while preventing the translocation of intestinal microbiota,which contribute to inflam-mation occurence. In inflammatory bowel disease (IBD),disruptions of intestinal barrier result in increased intestinal permeability which promotes the exposition to luminal content and triggers an immunological re-sponse that promotes intestinal inflammation. IBD patients demonstrate increased intestinal paracellular per-meability. Therefore,therapeutic target to restore the mucosal barrier may provide effective therapeutic and preventive approaches against IBD. This review examines the roles of the intestinal mucosal barrier on mecha-nisms underlying mucosal barrier dysfunction in IBD.
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Objective To study the antibacterial mechanisms of ethyl acetate extract (B06e) from the fermentation liquid of an endophytic fungus Alternaria spp. Alternaria spp isolated from the medicinal plant Humata tyermanni. Methods Double dilution method was adopted to measure the minimum inhibitory concentration (MIC) of B06e against Escherchia coli. Then, the changes of electric conductivity of bacterial culture, nucleic acid and protein concentration before and after treated by B06e were analysed, respectively. Besides, flow cytometry, scanning electron microscopy, gel retardation experiments, circular dichroism spectrum and Real-time quantitative PCR were introduced to study the antimicrobial mechanisms of B06e against E. coli. Results The results showed that MIC value of B06e against E. coli was 25 μg/mL. The electric conductivity of 3 × MIC treatment group was 1.01 times the value of the control group. The β-galactosidase activity of 3 × MIC treatment group was 11.6 times more than the value of the control group. Flow cytometry analysis showed that PI positive cells ratio of 3 × MIC treatment group was 286.5 times the value of the control group. Scanning electron microscopy showed that cell surface becomes rough after the treatment of B06e, a large number of cell membrane collapse. These results suggested that B06e can increase the permeability of cell membrane, destroy the integrity of cell membrane. The results of gel retardation experiments and circular dichroism spectrum applied that B06e can be inserted into DNA structure at particular position, however, can not cause DNA degradation. Real-time quantitative PCR results showed that the expressions of recA and recN genes were both up-regulated with the values of 2.9 and 3.7 times the value of the control group, respectively. This result suggested that B06e can destroy the DNA structure, which force E. coli to initiate SOS repair. Conclusion B06e can kill E. coli cell by destroying the cell membrane and damaging DNA structure.
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Objective To investigate the effect of ethyl acetate extract (B06e) from fermentation liquid of an endophytic fungus Alternaria spp. on the cell membrane integrity and the permeability of Staphylococcus aureus. Methods The minimum inhibitory concentration (MIC) of B06e against S. aureus was measured by double dilution method; The changes of electric conductivity of bacterial culture, A260 and A280 before and after treated by B06e were analyzed, respectively. Besides, the changes of cell membrane permeability before and after by B06e was measured by flow cytometry. The effect of B06e on the cell membrane structure was investigated by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Results The results showed that MIC value of B06e against S. aureus was 50 μg/mL. The conductivity of 3 × MIC treatment group was 1.06 times of the value of the control group; after treatment of B06e, the values of A260 and A280 were significantly higher than those of the control group: The beta-galactosidase activity of 3 × MIC treatment group was 9.43 times more than the value of the control group; Flow cytometry analysis showed that 3 × MIC treatment group by propidium iodide (PI) staining of positive cells was 47.63 times more than the control group; SEM and FT-IR analysis showed that the structure of bacterial cell changed after B06e treatment. Conclusion B06e can kill S. aureus cell by increasing the permeability of its cell membrane and destroy cell membrane integrity.
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Objective To investigate the bactericidal mechanism of electrolyzed oxidizing water (EOW) against Pseudomona aeruginosa (P.aeruginosa).Methods Bactericidal mechanism of EOW against P.aeruginosa was studied through intracellular protein leakage,nucleic acid,and cell membrane calcium ion permeability,2 ％ glutaraldehyde was used as positive control group,and normal saline (NS) was used as negative control group.Results The killing rates of EOW and 2％ glutaraldehyde to P.aeruginosa were both＞99.99％ with 30-second contact time,and 100.00％ with 60-second contact time.After 60-second contact with EOW,NS,and 2％ glutaraldehyde,the protein leakage of P.aeruginosa detected by bicinchoninic acid (BCA) were (96.00 ± 7.42),(94.15 ± 7.49),and (216.97 ± 10.35)μg/mL,respectively,difference was significant(F =613.20,P＜0.01),2％ glutaraldehyde group was higher than EOW group and NS group;protein leakage did not change with the increase of contact time(all P＞0.05).Electrophoretogram of random amplified polymorphic DNA showed high intensity dense band between 500-1000 Kb in EOW group and NS group,while 2％ glutaraldehyde group was without amplified bands.The fluorescence intensity of calcium ion of EOW group and 2％ glutaraldehyde group were both lower than that of NS group.Conclusion Bactericidal mechanism of EOW may be due to the damage of membrane permeability of P.aeruginosa,which causes Ca2+ leakage,but fails to cause protein leakage,the damage to nucleic acid is not obvious,DNA may not be a bactericidal target of EOW.
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Objective To explore the bioeffect of different parameters on 4 cell lines by ultrasoundmediated microbubble destruction.Methods The orthogonal experimental design was used to investigate the effect of three factors on the bioeffects of four cell lines under three levels.Three factors included microbubble concentration,sound intensity,irradiation time.Human breast tumor (MCF-7) cells,ovarian tumor (A2780) cells,liver tumor (Bel7402) cells and thyroid tumor (ARO) cells were exposed to ultrasound in the presence of SonoVue.The cell survival rate was determined by MTT methods and the cell luminosity factor was detected by flow cytometry.Results The optimum parameters for Bel7402 and ARO cell were the same (A2B3C2),and they were different from those from MCF-7 (A3B1C1) and A2780 (A1B3C3) cell.The cell survival rates for 4 cell lines were above 75％,and the cell luminosity factors were different among 4 cell lines.Conclusions The optimum parameters by ultrasound-mediated microbubble destruction for different cell lines are different,and under the optimum parameters the bioeffects of different cell lines are different.
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Background Age-related cataract is a common cause of blindness.However,its cause and pathogenic mechanism have not been fully understood.Recent studies revealed that aquaporin 1 (AQP1) and AQP0 are closely related to the pathogenesis of cataract.Objective This study was to investigate the differential distribution and expression of AQP0 and AQP1 in lenses with age-related cataract and explore its effect on pathogenesis of age-related cataract.Methods Seventeen anterior capsular membrane samples and nucleus samples of lenses were collected from age-related cataract patients during the small incision nonphacoemulsification cataract extraction,and 6 normal lens samples were obtained from health donors in the First Affiliated Hospital of Fujian Medical University.The expression and distribution of AQP1 and AQP0 in the lenses were detected by immunohistochemistry,and the relative expression levels of AQP1 and AQP0 proteins in the lenses were assayed by using Western blot assay.This study protocol was approved by Ethic Committee of this hospital,and written informed consent was obtained from each patient.Results Immunohistochemistry showed that in the normal lenses,AQP1 expressed mainly in LECs;while AQP0 primarily expressed in fiber cells of the lens cortex and nucleus.The relative expression levels of AQP1 and AQP0 in the lenses with age-related cataract (absorbance) were 0.223±0.008 and 0.118±0.015,which were significantly lower than 0.246±0.007 and 0.149±0.007 in the normal lenses (t =-4.508,-3.291,both at P＜0.01).Western blot revealed that the relative expression levels of AQP1 and AQP0 in the lenses with age-related cataract (absorbance) were 0.663 ± 0.012 and 0.599 ± 0.015,which were significantly reduced in comparison with 0.844±0.041 and 0.955 ±0.064 in the normal lenses (t =-7.492,P＜0.05;t =-9.570,P＜0.01).Conclusions AQP1 and AQP0 distribute in different sites of lenses.The expressions of AQP1 and AQP0 are obviously down-regulated in lenses with age-related cataract,suggesting that AQP1 and AQP0 probably play different roles in the pathogenesis of age-related cataract.
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Objective To investigate the effect of Paeonia lactiflora formula granule (PLFG) against the damage of LO2 cells induced by carbon tetrachloride (CCl4) and explore its mechanism. Methods LO2 cells were divided into control group, CCl4 model group, PLFG (1, 5, 10mg/L) groups and Vit E (50mmol/L) group. LO2 cells of PLFG groups and Vit E group were pretreated by drugs for 24 hours, then except control group, other groups were treated by 10mmol/L CCl4 for 6 hours, which induced hepatic cell damage, the alanine aminotransferase (ALT) and aspartate transaminase (AST) content of the cell culture supernatant were measured, the survival rates of LO2 cells were analyzed by MTT method. LO2 cells were divided into control group, CCl4 model group, PLFG (10mg/L) group and Vit E (50mmol/L) group, cell loss, changes in nuclear size and morphology, DNA content, mitochondrial membrane potential (MMP), cell permeability changes, and cytochrome C release were measured simultaneously by high content analysis (HCA). Results Compared with CCl4 model group, PLFG and Vit E pretreatment could obviously decrease the level of ALT and AST (P<0.05 or P<0.01), especially in the 10mg/L PLFG group and Vit E group. PLFG (1, 5, 10mg/L) and Vit E could also significantly weaken the decrease of LO2 cell viability, which were induced by CCl4 treatment, the results showed in dose-dependent to some extents (P<0.05 or P<0.01). Meanwhile, treatment with 10mg/L PLFG and Vit E could significantly increase the level of MMP (P<0.01), prevent cytochrome C release (P<0.01), decrease the membrane permeability (P<0.01), increase nuclear size (P<0.01), decrease total nuclear intensity (P<0.01) and increase the cell count (P<0.05). Conclusion PLFG may act an obvious protective effect against the liver injury induced by CCl4, and it might be due to protecting the integrity of mitochondria membrane, decreasing cell membrane permeability and inhibiting the apoptosis of LO2 cells.
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Objective To investigate the role of hypoxia?inducible factor?2α(HIF?2α) in the expression of tight junction proteins and permeability alterations in rat glomerular endothelial cells (rGENCs) under hypoxia condition. Methods The expressions of the HIF?2α and tight junction proteins such as occludin and ZO?1 of rGENCs were examined after exposed to 5%oxygen at different treatment time periods (0 h, 12 h, 24 h and 48 h). Then lentiviral transfection was used to knock down HIF?2α expression in rGENCs. The cells were split into four groups, including i) control group where rGENCs were cultured under normal oxygen conditions, ii) hypoxia group, iii) negative control group where rGENCs were infected with a negative vector, iv) HIF?2α lentivirus transfection group. Group ii, iii and iv were kept in hypoxic chamber (5% O2, 5% CO2 and 90% N2) for 24 h. The expressions of occludin, ZO?1 and HIF?2α were assessed by Western blotting. The permeability of rGENCs was measured using trans?epithelium electrical resistant (TEER) by Millicell? ERS voltohmmeter. Results With the elongation of hypoxia time, the expression of HIF?2α was increased gradually, while the occludin expression was decreased, there was statistically significance difference in each group (all P0.05). And a dramatic decrease in TEER of hypoxia cells was detected as compare with control cells (P0.05). Conclusion Hypoxia may promote HIF?2α expression, which could increase the permeability of rGENCs by reducing the expression of occludin and ZO?1.
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Objective To observe the postconditioning cardioprotective effects of atorvastatin (ATV) on ischemia-re?perfusion injury in isolated rat heart, and the role of phosphatidylinositol-3-kinase , protein kinase B(PI3K-Akt), mitochon?drial ATP-sensitive potassium (mito-KATP channel) and mitochondrial permeability transition pore (mPTP) thereof. Meth?ods Healthy male Wistar rats were randomly divided into 9 groups:ischemia reperfusion (I/R) control group, atorvastatin postconditioning (ATV) group, ATV plus PI3K inhibitor LY294002 (ATV+LY294002) group, LY294002 group, ATV plus mi?to-KATP channel inhibitor 5-hydroxydecanoate (ATV+5-HD) group, 5-HD group, ATV plus mPTP inhibitor ATR (ATV+ATR) group, ATR group and ethanol group. Model rats were given 30-min ischemia followed by 120-min reperfusion. The myocardial infarction size, hemodynamic parameters, creatine kinase isoenzyme (CK-MB), lactate dehydrogenase (LDH), nic?otinamide adenine dinucleotide (NAD+) and the expression of myocardial protein kinase B (Akt) and myocardial phospho-pro?tein kinase B (p-Akt) were evaluated. Results Compared with the control group, atorvastatin reduced the myocardial in?farction size, CK-MB and LDH(P<0.05), increased NAD+(P<0.05). There were no significant differences in the myocardi?al infarction size, CK-MB, LDH and NAD+between ATV+LY294002 group, ATV+5-HD group and ATV+ATR group. The hemodynamic parameters were improved in ATV group compared with those in control group. Western blot analysis con? firmed the significant phosphorylation of Akt in ATV group, ATV+5-HD group and ATV+ATR group compared with those of control group. There were no significant differences in the phosphorylation of Akt between ATV +LY294002 group, LY294002 group, ATR group and 5-HD group. Conclusion Atorvastatin postconditioning could attenuate the ischemia-re?perfusion injury through activating the PI3K-Akt, promoting mito-KATP channel opening and inhibiting mPTP opening.
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Objective To investigate the effect and mechanism of anti-tumor necrosis factor (TNF)-α on the intestinal mucosal permeability in dextran sulfate sodium (DSS) induced colitis mice.Methods Eighteen C57BL/6J mice were evenly divided into healthy control group,model group and anti-TNF-α treated group.The mice of model group and anti-TNF-α treated group were fed with 5％DSS solution for 7 days.The mice of anti-TNF-α treated group were injected anti-TNF-α (5 mg/kg)intraperitoneally on the first and fourth day; control group and model group were substituted with equal volume saline injection.The mice were sacrificed at 7 days after modeling.The disease activity index (DAI) score was evaluated everyday.The intestinal permeability was examined by Evan′s blue (EB) method and FITC-dextran (FITC-D) method.The colon tissue was collected for observation under microscope and histological index (HI).The small intestinal tissues were examined under electron microscope.The 10％ homogenate of colon and intestinal mucosa was prepared,the activity of myeloperoxidase (MPO),the content of TNF-α and epithelial myosin light chain kinase (MLCK) concentration were determined with kits respectively.The expression of MLCK in intestinal mucosa was tested by Western blot assay.Single factor of variance between groups were analyzed.Results Compared with control group,the DAI of model group increased daily.Compared with model group,the DAI of anti-TNF-α treated group improved.In model group,mice intestinal epithelial cells junctional complex shortened and widened and the cell gap expanded.In anti-TNF-α treated group,the connection structure of mice intestinal epithelial cells was tighter.The activity of HI and MPO and the content of TNF-α of model group were higher than those of control group (P ＝ 0.008,0.006 and 0.001,respectively),all of those of anti-TNF-α treated group were lower than those of model group (P=0.004,0.008 and 0.005,respectively).The F value of three groups was 131.98,218.28 and 58.93,respectively.The contents of EB in mice intestinal wall and serum FITC-D of model group were higher than those of control group (P=0.003 and 0.010),and those of anti-TNF-α treated group were lower model group (P＝0.001 and 0.009).The F value of three groups was 69.36 and 17.96.The MLCK concentration in mice intestinal mucosa of model group [(71.10± 7.52) ng/g] was higher than that of control group [(18.56±9.92) ng/g,P＜0.01],that of anti-TNF-α treated group [(37.56±15.84) ng/g] was lower than model group (P=0.008),and the difference among these three groups was statistically significant (F＝ 17.23).The Western blot results indicated the expression of MLCK in intestinal mucosa of model group was higher than that of control group,and that of anti-TNF-α treated group was lower than model group.Conclusions Anti-TNF-α play an important role in improving colitis,and the intestinal mucosal permeability.The mechanism may be related with the regulation of MLCK expression.
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Objective To evaluate the role of mitochondrial permeability transition pore (mPTP) in attenuation of myocardial ischemia-reperfusion (I/R) injury by sufentanil postconditioning in rats.Methods Sixty male Sprague-Dawley rats,aged 14-15 weeks,weighing 350-420 g,were randomly divided into 4 groups (n =15 each):sham operation group (group S),group I/R,cyclosporin A group (group CP) and sufentanil postconditioning group (group SP).Myocardial I/R was produced by occlusion of left anterior descending branch of coronary artcry for 30 min followed by reperfusion.In groups CP and SP,cyclosporin A 5 mg/kg and sufentanil 1 μg/kg were injected via the jugular vein at 5 min before reperfusion respectively,while the equal volume of normal saline was injected in group I/R.At 10 min of reperfusion,hearts were excised,the myocardial mitochondria were immediately isolated and the activity of mPTP was measured by spectrophotometry.MAP and HR were recorded at 30 min of equilibration,at 30 min of ischemia and at 120 min of reperfusion and rate-pressure product (RPP) was calculated.Arterial blood samples were obtained at 120 min of reperfusion for determination of the plasma cardiac troponin Ⅰ (cTnⅠ) concentration.The animals were then sacrificed for determination of infarct size (IS) and area at risk (AAR),and IS/AAR was calculated.The mitochondrial ultra-structure was examined with electron microscope.Results Compared with group S,the mPTP activity and plasma cTnI concentration were significantly increased,and MAP and RPP were significantly decreased in the other three groups (P ＜ 0.05).Compared with group I/R,the mPTP activity,plasma cTnI concentration and IS/ARR were significantly decreased in groups CP and SP,and MAP was significantly increased in group CP (P ＜ 0.05).Compared with group CP,MAP was significantly decreased (P ＜ 0.05),while no significant change was found in the other indexes in group SP (P ＞0.05).Significant mitochondrial swelling,and disruption and disappearance of cristae were showed in I/R group.The mitochondrial structure was more complete in CP and SP groups than that in group I/R,and the disrupted cristae were found in a small number of mitochondria in CP and SP groups.Conclusion The mechanism by which sufentanil postconditioning reduces myocardial I/R injury is related to inhibition of mPTP opening in rats.
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Objective To investigate the effects of ischemic postconditioning on mitochondrial permeability transition and mitochondrial transmembrane potential(△Ψm)following hepatic ischemia-reperfusion(I/R)in rats.Methods Forty male SD rats weighing 220-260 g were randomly divided into 5 groups with 8 animals in each group:sham operation group(group S);atractyloside+sham operation group(group A+S);I/R group;ischemic postconditioning group(group IPO)and atractyloside+ischemic postconditioning group(group A+IPO).The animals were anesthetized with intramuscular injection of atropine 0.05 mg/kg.Hepatic I/R was produced by occlusion of hepatic blood flow for 60 min followed by 6 h reperfusion.In group A+S,atractyloside 5 mg/kg was injected intravenously before abdomen Was closed.In group IPO,the animals were subjected to 3 cycles of 1 min reperfusion interspersed with 1 min hepatic isehemia at the end of 60 min hepatic ischemia.In group A+IPO,atractyloside 5 mg/kg was injected intravenously before reperfusion. Venous blood samples were collected for determination of serum ALT and AST activities immediately before ischemia and at 6 h of reperfusion. The animals were then sacrificed.Their livers were removed for microscopic examination, detection of apoptosis and determination of cytochrome c (Cyt c) expression, △Ψm and mitochonerial permeability transition pore (MPTP)activity. Apoptosis index (AI) was calculated. Results There was no significant difference in serum ALT and AST activities, AI, Cyt c expression, △Ψm and MPTP activity between S and A + S groups (P＞0.05). Compared with group S, serum ALT and AST activities and AI were significantly increased, Cyt c expression was up-regulated, △Ψm was decreased and MPTP activity was increased in groups I/R, IPO and A+IPO(P＜0.05).Compared with group I/R, serum ALT and AST activities and AI were significantly decreased,Cyt c expression was down-regulated, △Ψm was increased and MPTP activity was decreased in group IPO(P＜0.05), while no significant change was found in group A+IPO(P＞0.05).Compared with group IPO,serum ALT and AST activities and AI were significantly increased, Cyt c expression was up-regulated, △Ψm was decreased and MPTP activity was increased in group A + IPO(P＜ 0.05).Microscopic examination showed that hepatic injury was reduced in group IPO compared with group I/R, while aggravated in group A+ IPO compared with group IPO. Conclusion Ischemic postconditioning can protect liver from I/R injury by attenuating the I/R-induced increase in MPTP opening and decrease in △Ψm in rats.
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Objective To investigate the permeability changes of prostate cancer cells membrane under low intensity ultrasound in vitro.Methods The culture of monolayer adherent LNCaP prostate cancer cells in six-well plate was exposed to continuous ultrasound at frequency of 1 MHz.The cells membrane permeability (stained with Calcein)and cells viability(stained with PI)were evaluated by fluorescent microscope (FM) and cells morphological changes were evaluated by scanning electron microscope (SEM) under ultrasound with acoustic intensity of 160 mW/cm2 for 5 s.The rate of cells with increased cells membrane permeability as function of acoustic intensity (80 mW/cm2,120 mW/cm2 and 160 mW/cm2,for 5 s) and exposure duration (5 s,10 s and 15 s,acoustic intensity of 120 mW/cm2) was evaluated by flow cytometry.ResultsAfter low intensity of ultrasound,the cells with increased cell membrane permeability could be clearly shown with Calcein uptake under FM while no cell showed Calcein uptake in the control group.The SEM showed less microvilli on the cells after low intensity of ultrasound exposure and few cells showed holes on the cell membrane.The rate of cells with increased membrane permeability increased with acoustic intensity and exposure duration.Conclusion Low intensity ultrasound alone could increase membrane permeability of prostate cancer cells and cells with increased membrane permeability showed surface plane,uncommon holes on the cells membrane.The rate of cells with increased membrane permeability positively correlated with acoustic intensity and exposure duration.
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Objective To investigate the effects of pretreatment with Shen-fu injection on mitochondrial permeability transition and mitochondrial transmembrane potential (△ψm) following myocardial ischemiareperfusion (IR) injury in rats. Methods Thirty SD rats of both sexes weighing 250-300 g were randomly divided into3 groups with 10 animals in each group:Ⅰ sham operation group (group S); Ⅱ IR group and Ⅲ Shen-fu injection group (group SFI). The animals were anesthetized with intraperitoneal 20% urethane 5 ml/kg. The chest was opened and the heart exposed. Myocardial IR was induced by temporary ligation of the anterior descending branch of left coronary artery maintained for 30 min, followed by 120 min reperfusion. Myocardial ischemia was confirmed by decoloration of apex and elevation of S-T segment (＞ 0.1 mV) or erection of T wave. In group SFI,SFI 10 ml/kg was infused at 15 min before ischemia, while in group S and IR equal volume of normal saline was infused instead of SFI. At 120 min of reperfusion, blood samples were collected from right internal carotid artery for determination of serum concentration of cTnI. The animals were then sacrificed and the hearts were immediately removed for measurement of myocardial mitochonerial permeability transition pore (MPTP) activity (by spectrophotometry at 540 nm) and myocardial △ψm (by fluorospectrophotometer using rhodamine 123 as fluorescent probe). Results Compared with group S, serum cTnI concentration and MPTP activity were significantly increased and △ψm was decreased in group IR. SFI pretreatment significantly attenuated the IRinduced increase in serum cTnI concentration and the MPTP activity and decrease in △ψm. Conclusion SFI pretreatment can protect myocardium from IR injury by attenuating the IR induced increase in MPTP opening and decrease in △ψm.
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Objective To investigate the role of mitochondrial respiratory chain in the hyperpermeability of human peritoneal mesothelial cells (HPMCs) induced by high glucose peritoneal glucose PDS was also added. Transmesothelial electrical resistance (TER) measurement was examined for detection of permeability damage in HPMCs. Immunostaining and Western blotting analysis were used to detect claudin-1 expression. Mitochondrial superoxide (MitoSOX) Red staining and respiratory chain complexes activities were determined for detection of mitochondrial reactive oxygen species (ROS) production and mitochondrial complexes activities. Results TER was decreased in a time- and concentration-dependent manner after culture with high glucose PDS for was also down-regulated significantly by high glucose PDS (P＜0.01). Complex Ⅲ activity was inhibited (10.8% of control, P＜0.01) accompanied with increased mitochondrial ROS generation.These changes were partially prevented by glutathione. Conclusion Mitochondrial respiratory complex Ⅲ pathway has crucial importance in maintaining TER of HPMCs, which may reveal a valuable target for novel therapies to fight hyperpermeability of peritoneum during the prolonged PD treatment.
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Objective To investigate the effects of desflurane inhalation on pulmonary alveolar-capillary membrane permeability and the inflammatory cell counts in broncho-alveolar lavage fluid (BALF) during endotoxin-induced acute lung injury in rats. Methods Forty-eight Wistar rats weighing 200-290 g were anesthetized with intraperitoneal pentobarbital 100mg?kg-1 , tracheotomized and mechanically ventilated. PETCO2 was maintained at 35-45 mm Hg (VT 8 ml?kg-1 , RR 65-70 bpm). Right carotid artery and left femoral vein were cannulated for BP monitoring and fluid and drug administration. The animals were randomly divided into four group with 12 animals in each group : (1) control group received normal saline (NS) 1.2 ml i.v. followed by 4 h mechanical ventilation; (2) LPS group received LPS (055:B5, Sigma) 5 mg?kg-1 followed by 4h mechanical ventilation; (3)Desflurane group A and B received LPS 5 mg? kg-1 followed by desflurane inhalation for 4 h at 1 MAC (desflurane group A) or 1.5 MAC (desflurane group B) . Six animals in each group received Evans blue 50 mg?kg-1 at the beginning of the experiment for determination of pulmonary alveolar-capillary membrane permeability at the end of the experiment. The animals were sacrificed by exsanguinations at the end of 4h mechanical ventilation. Blood was collected for determination of total plasma protein concentration. Lungs were removed. The right lung was lavaged and BALF was collected for determination of protein content, and differential inflammatory cell counts. The left lung was used for microscopic examination. The morphologic changes were scored 0-3 (0 = normal, 3 = severe morphologic changes). In addition wet/dry lung weight ratio, pulmonary permeability index (BALF protein concentration /total plasma protein concentration?10-3 ) and mortality rate were also determined. Results In group 3 (desflurane 1 MAC) W/D lung weight ratio and lung water content significantly increased compared with those in LPS group. In group 4 ( desflurane 1.5 MAC) W/D lung weight ratio, lung water content, pulmonary permeability index, Evans blue content in lung tissue, morphological change scores and mortality rate were all significantly increased compared with LPS group (group 2). There was no significant difference in total and differential inflammatory cell counts in BALF between group 2 and 4.Conclusion Desflurane inhalation is detrimental to the lungs acutely injured by endotoxin in a dose-dependent manner.
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AIM: Through studying the differences between wild-type acidic fibroblast growth factor (waFGF) with recombinant aFGF (raFGF), the biological effect of raFGF concerned with mitogenic activity was evaluated. METHODS: NIH3T3 cell line was used. Cell proliferation with MTT method was used to study the mitogenic activity. Flow cytometry was also used for detection of apoptosis, cell membrane permeability and mitochondria potential. The role of heparin sulfate (HS) on aFGF biological effect was studied at the same time in this research. RESULTS: The enhancement of raFGF on cell proliferation was significantly lower than that of waFGF. The restriction of raFGF on apoptosis and the enhancement of it on cell membrane permeability were all lower than those of waFGF significantly. The enhancement of raFGF on mitochondria potential was lower than that of waFGF significantly. The HS improved the biological effect of aFGF. CONCLUSION: The mitogenic activity of raFGF is lower than that of waFGF and raFGF has little effect on apoptosis.
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AIM: To investigate the effects of stress on the opening of mitochondrial membrane permeability pore (PTP) in rat heart and explore the possible molecular mechanism underlying PTP opening. METHODS: Stress animal model was established. After strained for differnet time, all rats were killed and PTP opening degree were examined by spectrophotometer. Bcl-2, Bax expression levels were determined by Western blot. RESULTS: Stress induced PTP opning, Bcl-2 expression inhibition and Bax level elevation in myocardial mitochondria. CONCLUSION: PTP opening was the important mitochondrial mechanism of stress-induced heart injury. Decrease in Bcl-2 expression and increase of Bax level may be an important molecular basis for PTP opening.
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Fresh healthy human erythrocytes were treated by four kinds of bile acid solutions (DC, GDC, C, and GC) at physiological and pathological concentrations of human plasma, and the membrane proteins, enzyme activities and permeability of cations were observed. The results showed that some components of the membrane cytoskeleton proteins disappeared, the activities of total ATPase and Gr-ATPase were distinctly increased with the increasing of bile acid concentrations, the activity of the membrane acetylcholinesterase was decreased with the increasing bile acid concentrations, the permeability of cations was increased with the increasing bile acid concentrations. The effect of the dihydroxy bile acids more stronger than that of the trihydroxy bile acids.