Effect of sleeve gastrectomy on renal oxidative stress in type 2 diabetic rats / 国际外科学杂志

Objective@#To investigate the changes of oxidative stress in kidney of type 2 diabetic rats after sleeve gastrectomy and its effect on renal function.@*Methods@#Twenty male SD rats were fed with high-fat diet and injected with streptozotocin intraperitoneally to induce type 2 diabetes mellitus. Seventeen successful induction models were divided into sham operation group (n=7) and sleeve gastrectomy (SG) group (n=10) by random number table method, and were treated with sham operation and SG respectively. The body weight, 24-hour food intake, fasting blood glucose (FBG)and serum glucagon-like peptide-1 (GLP-1) were measured before and 1, 2, 3 and 4 weeks after operation. The activities of superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px) and malondialdehyde in renal tissue as well as blood urea nitrogen (BUN), creatinine levels and 24-hour urinary microalbumin (UALB) were measured 4 weeks after operation. Masurement data conforming to normal distribution were expressed as Mean±SD, and t-test was used for comparison between two groups.@*Results@#At the 1st, 2nd, 3rd, 4th weeks after operation, the levels of FBG in SG group was lower than those in sham operation group [(11.13±3.27) mmol/L vs (16.74±4.10) mmol/L, (9.53±2.82) mmol/L vs (19.31±3.66) mmol/L, (6.69±2.44) mmol/L vs (20.84±2.71) mmol/L, (6.58±2.96) mmol/L vs (19.99±2.85) mmol/L, all P<0.05]. In the same period, the levels of serum GLP-1 in SG group was higher than those in sham operation group [(22.61±2.92) pg/mL vs (15.42±2.39) pg/mL, (24.72±3.02) pg/mL vs (16.20±2.26) pg/mL, (24.59±2.85) pg/mL vs (15.84±2.75) pg/mL, (26.15±3.23) pg/mL vs (15.77±2.79) pg/mL, all P<0.05]. At the 4th week after operation, BUN[(5.34±0.82) mmol/L], creatinine[(39.78±6.13)]μmol/L, UALB[(31.18±6.88) mg/24 h] and renal creatinine[(5.84±0.85) nmol/mg] in SG group were lower than those in sham operation group [BUN (9.08±1.54) mmol/L, creatinine (64.07±8.63) μmol/L, UALB (67.64±9.07) mg/24 h, creatinine (10.78±1.28) nmol/mg], and the differences were statistically significant (all P<0.05). Renal SOD[(620.05±55.98) U/mg], CAT[(24.72±2.28) U/mg] and GSH-Px[(281.53±27.99) U] in SG Group were lower than those in sham operation group [SOD(392.52±45.97) U/mg, catalase (15.62±2.46) U/mg, GSH-Px (164.71±21.83) U], and the differences were statistically significant (all P<0.05).@*Conclusion@#Sleeve gastrectomy may improve renal function through reducing oxidative stress in the kidney.

Effect of sleeve gastrectomy on renal oxidative stress in type 2 diabetic rats / 国际外科学杂志

Objective To investigate the changes of oxidative stress in kidney of type 2 diabetic rats after sleeve gastrectomy and its effect on renal function.Methods Twenty male SD rats were fed with high-fat diet and injected with streptozotocin intraperitoneally to induce type 2 diabetes mellitus.Seventeen successful induction models were divided into sham operation group (n =7) and sleeve gastrectomy (SG) group (n =10) by random number table method,and were treated with sham operation and SG respectively.The body weight,24-hour food intake,fasting blood glucose (FBG)and serum glucagon-like peptide-1 (GLP-1) were measured before and 1,2,3 and 4 weeks after operation.The activities of superoxide dismutase (SOD),catalase,glutathione peroxidase (GSH-Px) and malondialdehyde in renal tissue as well as blood urea nitrogen (BUN),creatinine levels and 24-hour urinary microalbumin (UALB) were measured 4 weeks after operation.Masurement data conforming to normal distribution were expressed as Mean ± SD,and t-test was used for comparison between two groups.Results At the 1st,2nd,3rd,4th weeks after operation,the levels of FBG in SG group was lower than those in sham operation group [(11.13 ±3.27) mmol/L vs (16.74 ±4.10) mmol/L,(9.53 ±2.82) mmol/L vs (19.31 ±3.66) mmol/ L,(6.69 ±2.44) mmol/L vs (20.84 ±2.71) mmol/L,(6.58 ±2.96) mmol/L vs (19.99 ±2.85) mmol/L,all P ＜ 0.05].In the same period,the levels of serum GLP-1 in SG group was higher than those in sham operation group [(22.61 ± 2.92) pg/mL vs (15.42 ± 2.39) pg/mL,(24.72 ± 3.02) pg/mL vs (16.20 ± 2.26) pg/mL,(24.59 ±2.85) pg/mL vs (15.84±2.75) pg/mL,(26.15 ±3.23) pg/mL vs (15.77 ±2.79) pg/mL,all P＜ 0.05].At the 4th week after operation,BUN[(5.34 ±0.82) mmol/L],creatinine[(39.78 ±6.13)] μmoL/L,UALB [(31.18 ± 6.88) mg/24 h] and renal creatinine [(5.84 ± 0.85) nmol/mg] in SG group were lower than those in sham operation group [BUN (9.08 ± 1.54) mmol/L,creatinine (64.07 ± 8.63) μmol/L,UALB (67.64 ±9.07) mg/24 h,creatinine (10.78 ± 1.28) nmol/mg],and the differences were statistically significant (all P＜0.05).Renal SOD[(620.05 ±55.98) U/mg],CAT[(24.72 ±2.28) U/mg] and GSH-Px[(281.53 ± 27.99) U] in SG Group were lower than those in sham operation group [SOD(392.52 ± 45.97) U/mg,catalase (15.62 ± 2.46) U/mg,GSH-Px (164.71 ± 21.83) U],and the differences were statistically significant (all P ＜ 0.05).Conclusion Sleeve gastrectomy may improve renal function through reducing oxidative stress in the kidney.

Superoxide Anion Production by the Spermatozoa of Men with Varicocele: Relationship with Varicocele Grade and Semen Parameters

PURPOSE: To investigate the pathophysiological role of superoxide anion and total reactive oxygen species (ROS) production by the spermatozoa of men with varicocele and its relationship with varicocele grade and semen parameters. MATERIALS AND METHODS: This prospective study included 34 men with grade II–III varicocele, regardless of their fertility status. The control group consisted of 13 healthy men. Semen characteristics were examined according to the 2010 World Health Organization criteria. The swim-up method was used for sperm preparation. Total ROS and superoxide anion production was assayed by luminol- and lucigenin-dependent chemiluminescence (CL), respectively. RESULTS: The men with varicocele had significantly higher total ROS and superoxide anion levels than the healthy control subjects (2.9±0.4 relative light unit (RLU) vs. 2.4±0.1 RLU, p=0.001 for luminol-dependent CL and 2.8±0.4 RLU vs. 2.3±0.2 RLU, p=0.002 for lucigenin-dependent CL). Cases of grade III varicocele had significantly higher superoxide anion and total ROS levels than grade II cases and control subjects (p < 0.001). Superoxide anion and total ROS levels were negatively correlated with all semen parameters. CONCLUSIONS: The superoxide anion levels produced by spermatozoa were significantly higher in varicocele patients than in control subjects. ROS production was related to increased varicocele grade, impaired semen concentration, and abnormal morphology in men with varicocele. Our findings suggest that superoxide anion overproduction may be an important step in the cascade of ROS-related damage to spermatozoa, resulting in impaired semen parameters in patients with varicocele.

Efeito da ressuscitação volêmica precoce na resposta inflamatória e no estresse oxidativo cardiovascular do choque séptico experimental / SvO2 guided resuscitation for experimental septic shock: effects of fluid infusion and dobutamine on hemodynamics, inflammatory response and cardiovascular oxidative stress

Os mecanismos fisiopatológicos associados aos efeitos benéficos da reanimação guiada pela saturação venosa mista de oxigênio (SvO2) durante a sepse não são claros. Nosso objetivo foi avaliar os efeitos de um algoritmo de reanimação guiado pela SvO2 incluindo fluidos, noradrenalina e dobutamina na hemodinâmica, resposta inflamatória e estresse oxidativo cardiovascular durante um modelo experimental que se assemelha clinicamente ao choque séptico. Dezoito porcos anestesiados e cateterizados (35-45 kg) foram submetidos à peritonite por inoculação fecal (0,75 g/Kg). Depois de permanecerem hipotensos, antibióticos foram administrados e os animais foram randomizados em dois grupos: controle (n=9), com suporte hemodinâmico visando pressão venosa central de 8-12 mmHg, débito urinário de 0,5 ml/kg por hora, e pressão arterial média acima de 65 mmHg; e grupo SvO2 (n=9), com os objetivos acima referidos, além de SvO2 acima de 65%. As intervenções duraram 12 hs e incluíram Ringer Lactato e norepinefrina (ambos os grupos) e dobutamina (grupo SvO2). A resposta inflamatória foi avaliada pela concentração plasmática de citocinas, expressão de CD14 de neutrófilos, geração de espécies reativas de oxigênio e apoptose. O estresse oxidativo foi avaliado pelas concentrações de nitratos no miocárdio e no plasma, a atividade miocárdica e vascular de NAD(P)H oxidase, conteúdo de glutationa do miocárdio e expressão de nitrotirosina. A reanimação guiada por SvO2 foi associada com melhor índice sistólico, oferta de oxigênio e diurese. A sepse induziu em ambos os grupos um aumento significativo na concentração de IL-6, nas concentrações de nitrato de plasma e diminuição persistente na expressão de CD14 em neutrófilos. A apoptose e a geração de espécies reativas de oxigênio por neutrófilos não foram diferentes entre os grupos. As estratégias de tratamento não alteraram significativamente os parâmetros de estresse oxidativo. Assim, uma abordagem destinada a otimizar a SvO2...

The pathogenetic mechanisms associated to the beneficial effects of mixed venous oxygen saturation (SvO2)-guided resuscitation during sepsis are unclear. Our purpose was to evaluate the effects of an algorithm of SvO2-driven resuscitation including fluids, norepinephrine and dobutamine on hemodynamics, inflammatory response and cardiovascular oxidative stress during a clinically resembling experimental model of septic shock. Eighteen anesthetized and catheterized pigs (35-45 Kg) were submitted to peritonitis by fecal inoculation (0.75 g/Kg). After hypotension, antibiotics were administered, and the animals were randomized to two groups: control (n=9), with hemodynamic support aiming central venous pressure 8 to 12 mmHg, urinary output 0.5 ml/Kg per hour, and mean arterial pressure greater than 65 mmHg; and group SvO2 (n =9), with the goals above, plus SvO2 greater than 65%. The interventions lasted 12 h, and lactated Ringer's and norepinephrine (both groups) and dobutamine (SvO2 group) were administered. Inflammatory response was evaluated by plasma concentration of cytokines, neutrophil CD14 expression, oxidant generation, and apoptosis. Oxidative stress was evaluated by plasma and myocardial nitrate concentrations, myocardial and vascular NAD(P)H oxidase activity, myocardial glutathione content, and nitrotyrosine expression. Mixed venous oxygen saturation-driven resuscitation was associated with improved systolic index, oxygen delivery, and diuresis. Sepsis induced in both groups a significant increase on IL-6 concentrations and plasma nitrate concentrations and persistent decrease in neutrophil CD14 expression. Apoptosis rate and neutrophil oxidant generation were not different between groups. Treatment strategies did not significantly modify oxidative stress parameters. Thus, an approach aiming SvO2 during sepsis improves hemoynamics, without any significant effect on inflammatory response and oxidative stress. The beneficial effects...

The clinical observation of ketamine attenuates neutrophil activation after cardiopulmonary bypass / 重庆医学

Objective To investigate the application of small dose of ketamine during induction of anesthesia in patients after coronary artery bypass grafting neutrophil superoxide generation effect .Methods 30 patients undergoing elective coronary artery bypass grafting operation were randomly divided into 2 groups ,in the fentanyl induced respectively based on combined with small dose of ketamine (ketamine group) or normal saline (control group) ,a blood sample collection time points :before ,immediately after extracorporeal circulation operation ,operation after 1-6 days .Neutrophil function by using (12-) fourteen acid and phorbol ester (-13-) acetate (PMA) ,yeast polysaccharide or formyl-methylthio-light-phenylalanine after stimulation of superoxide production de-termination method .Results During general anesthesia combined with low dose ketamine inhibits superoxide anion increases .In ad-dition ,ketamine reduces perioperative 2 -6 days of the neutrophil percentage .Conclusion Ketamine can reduce the activation of neutrophils after cardiopulmonary bypass .

NADPH oxidase and cerebral ischemia-reperfusion injury / 国际脑血管病杂志

NADPH oxidases are a family of multi-subunit enzyme eomplexes.It catalyzes the production of reactive oxygen species (ROS).A large number of studies have shown that oxidative stress plays a very important role in cerebral ischemia-reperfusion injury,and the find of the expression changes about NADPH oxidase after cerebral ischemia may provide a new idea for the prevention and treatment of ischemic stroke.NADPH oxidase may become a new therapeutic target.

Effect of heshouwuyin on antioxygen capability of aging rat ovaries / 中国基层医药

ObjectiveTo find the mechanism of Heshouwuyin(HSWY) in anti-aging, so as to provide theoretical and experiment evidence for the application of HSWY. Methods50 eight-week female SD rats ( SPF degree)were used in this study. The rats were randomly divided into 5 groups:normal control group, 10 rats; model group,10 rats; HSWY anti-aging group, including low, middle and high dose group,10 rats in each group. The sub-acutely aging rats were made by ip injection of D-galactose for 60 days continually. The rats in HSWY groups were administered with various doses of intragastric HSWYduring D-galactose injection. The parameters of ovary levels of SOD,GSH-PX, TAOC were detected. ResultsThe MDA in ovaries of model rats was significantly higher than that of negative control group;while the SOD, GSH-PX, TAOC of model rats were significantly lower than negative control group.The MDA content in ovaries after taking HSWY was significantly lower than that of model rats; while the SOD, GSHPX,TAOC of the taking HSWY rats was significantly higher than that of model rats. ConclusionThe HSWY could increase antioxida tive activity of rat ovaries to stay D-galactose induced consenescence.

Influence of Hydrogen Peroxide on Mitochondrial Membrane Potential and Superoxide Production in FRTL Cell / 天津医药

Objective:To investigate the effects of exogenous hydrogen peroxide(H_2O_2)on mitochondrial superoxide production and mitochondrial membrane potential changes(△ψ)in fisher rat thyroid cell line(FRTL).Methods:Following 1 mmol/L H_2O_2 exposure in FRTL cells for 10 min,30 min and 24 h,mitochondrial superoxide production was measured by living cell imaging and flow cytometry using MitoSOX.The mitochondrial membrane potential was assayed by spectrofluorimeter and fluorescent microscopy using rhodamine 123(rh123).The cell viability was detected by MTT colorimetric method.Morphological changes were observed by invert microscope.Apoptosis assay was performed by acridine orange staining.Results:Quantitative measurements of the mean intensities of MitoSOX demonstrated significant increase with 1 mmol/L H_2O_2 following 10 min,30 min and 24 h treatment in FRTL cells compared with that of control.Fluorescence intensity of rh123 and optical density of MTr were significantly decreased in FRTL ceils with 1 mmol/L H_2O_2 following 30 min and 24 h treatment(P ＜ 0.01).Under light microscope and fluorescence microscope the characteristic morphological features of programmed cell death,pickuosis,karyorrhexis,and cell shrinkage were observed after acridine orange staining.Conclusion:Acute and chronic exogenous H_2O_2 exposure cause oxide stress in FRTL cells,which result in the increase of mitochondrial superoxide production,△ψdecline,cell necrosis and apoptosis.

Effects of iodine excess on mitochondrial superoxide production and mitochondrial membrane potential in rat thyroid cell line cells / 中国地方病学杂志

Objective To investigate the effects of iodine excess on mitochondrial superoxide production and mitoehondrial membrane potential(△ψ)changes in Fisher rat thyroid cell line(FRTL)cells.Methods FRTL cells were treated with 10-4mol/L potassium iodine(KI),10 U/L thyrotropin(TSH),10-4 mol/L KI+10 U/L TSH respectively for 24 h.Effects on cell proliferation were assayed by methyl thiazolyl tetrazolium(MTT)colorimetric method.Changes of mitochondrial superoxide production and △ψ were measured by live cell imaging and spectrofluorometer using MitoSOX and rhodamine 123(rh123)respectively.Results Absorbance(A)in the KI group (0.794±0.144)showed a significant decline compared to the control group(1.000 ±0.183,P<0.05),whereas a significant elevation was observed in the TSH group(1.215±0.156,P<0.05).No significant differences was found between the KI+TSH group(1.025±0.254)and the control group(P>0.05),but the former was marked higher than the KI group(P<0.05).Compared to the control group(9.74±3.24).MitoSOX mean fluorescence intensity (MFI)in the KI and KI+TSH groups(18.16±6.57,13.33±2.92)were significantly increased(all P<0.05),which was a significant decline in the TSH group(6.64±2.15,P<0.05).MitoSOX MFI in the KI+TSH group was lower than the KI group(P<0.05).Rh123 MFI in the KI and KI+TSH groups(210 593±31 328,295 525±34 243)showed significant decline than the control group(407 824±37 198,all P<0.05).Compared with the KI group.the KI+TSH group pronouncedly attenuated the reduction of Rh 123 MFI(P<0.05).No significant differences of Rh 123 MFI were found between the TSH group(411 187 ± 72 852) and the control group(P > 0.05). Conclusion Iodine excess (10-4 mol/L KI) may lead to peroxide damage on the mitochondria of FRTL cells, and cell proliferation is inhibited. Combining treatment with 10 U/L TSH may attenuate mitochondrial peroxide damage and inhibition of cell proliferation caused by iodine excess.

Piceatannol-3'-O-beta-D-glucopyranoside as an active component of rhubarb activates endothelial nitric oxide synthase through inhibition of arginase activity

Arginase competitively inhibits nitric oxide synthase (NOS) via use of the common substrate L-arginine. Arginase II has recently reported as a novel therapeutic target for the treatment of cardiovascular diseases such as atherosclerosis. Here, we demonstrate that piceatannol-3'-O-beta-D-glucopyranoside (PG), a potent component of stilbenes, inhibits the activity of arginase I and II prepared from mouse liver and kidney lysates, respectively, in a dose-dependent manner. In human umbilical vein endothelial cells, incubation of PG markedly blocked arginase activity and increased NOx production, as measured by Griess assay. The PG effect was associated with increase of eNOS dimer ratio, although the protein levels of arginase II or eNOS were not changed. Furthermore, isolated mice aortic rings treated with PG showed inhibited arginase activity that resulted in increased nitric oxide (NO) production upto 78%, as measured using 4-amino-5-methylamino-2',7'-difluorescein (DAF-FM) and a decreased superoxide anions up to 63%, as measured using dihydroethidine (DHE) in the intact endothelium. PG showed IC50 value of 11.22 microM and 11.06 microM against arginase I and II, respectively. PG as an arginase inhibitor, therefore, represents a novel molecule for the therapy of cardiovascular diseases derived from endothelial dysfunction and may be used for the design of pharmaceutical compounds.

Efeito da desnutrição neonatal sobre o recrutamento celular e a atividade oxidante-antioxidante de macrófagos em ratos adultos endotoxêmicos / Effect of neonatal malnutrition on cell recruitment and oxidant-antioxidant activity of macrophages in endotoxemic adult rats

OBJETIVO: Avaliar se a desnutrição no período neonatal produz prejuízos no recrutamento celular para o pulmão e na atividade oxidante-antioxidante de macrófagos alveolares em ratos adultos endotoxêmicos. MÉTODOS: Ratos machos Wistar (n=48) foram alimentados por mães cuja dieta, durante a lactação, continha 23 por cento de proteína no grupo nutrido e 8 por cento no grupo desnutrido. Após o desmame todos os animais foram recuperados com dieta normoprotéica. Entre 90 e 120 dias, a metade de cada grupo foi submetida à endotoxemia por meio da administração por via intraperitonial (v.i) de lipopolissacarídio na dose de 1mg/kg de peso corporal. Após 24 horas desse procedimento coletou-se o sangue para contagem total e diferencial de leucócitos e para a dosagem de óxido nítrico. Além do sangue coletou-se também o lavado broncoalveolar para contagem total e diferencial de leucócitos e, a partir de macrófagos isolados deste lavado, foram realizadas as dosagens de superóxido, óxido nítrico e superóxido dismutase. RESULTADOS: A desnutrição acarretou um déficit ponderal que persistiu até a idade adulta, além disso, reduziu a contagem total de leucócitos sangüíneos e o número de neutrófilos após o estímulo com lipopolissacarídio. A atividade oxidante-antioxidante foi alterada havendo diminuição da produção de superóxido, óxido nítrico e superóxido dismutase antes e após a indução da endotoxemia. CONCLUSÃO: Esses resultados sugerem que a desnutrição neonatal, mesmo após a recuperação nutricional, compromete o recrutamento celular para o pulmão e a atividade oxidante-antioxidante dos macrófagos alveolares em ratos adultos. A endotoxemia contribui para evidenciar essas seqüelas da resposta do hospedeiro frente a este modelo de desnutrição.

OBJECTIVE: The objective of this study was to assess if neonatal malnutrition impairs cell recruitment to the lungs and the oxidant-antioxidant activity of alveolar macrophages in adult endotoxemic rats. METHODS: Male Wistar rats (n=48) were divided into two groups and suckled by dams fed experimental diets containing a normal protein content of 23 percent (nourished group) and a low protein content of 8 percent (undernourished group) during lactation. After weaning, all animals received a normal protein diet. Between 90 and 120 days, half of each group was submitted to endotoxemia by intraperitoneal administration of 1mg/kg of body weight of lipopolysaccharide. Blood was collected 24 hours after this procedure for total and differential leukocyte count and measurement of nitric oxide. Bronchoalveolar lavage was also done to determine total and differential leukocyte count and measure superoxide, nitric oxide and superoxide dismutase in the macrophages isolated from this lavage. RESULTS: Malnourished animals remained underweight until adulthood. Furthermore, the following also decreased: total blood leukocyte count, number of neutrophils after lipopolysaccharide administration and production of superoxide, nitric oxide and superoxide dismutase before and after induced endotoxemia. CONCLUSION: These results suggest that neonatal malnutrition, even after nutritional recovery, compromises cell recruitment to lungs and the oxidant-antioxidant activity of alveolar macrophages of adult rats. Endotoxemia contributes to evidence these sequelae to the host response before this model of malnutrition.

Microglia, major player in the brain inflammation: their roles in the pathogenesis of Parkinson's disease

Inflammation, a self-defensive reaction against various pathogenic stimuli, may become harmful self-damaging process. Increasing evidence has linked chronic inflammation to a number of neurodegenerative disorders including Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis. In the central nervous system, microglia, the resident innate immune cells play major role in the inflammatory process. Although they form the first line of defense for the neural parenchyma, uncontrolled activation of microglia may directly toxic to neurons by releasing various substances such as inflammatory cytokines (IL-1beta, TNF-alpha, IL-6), NO, PGE

Downstream components of RhoA required for signal pathway of superoxide formation during phagocytosis of serum opsonized zymosans in macrophages

Rac1 and Rac2 are essential for the control of oxidative burst catalyzed by NADPH oxidase. It was also documented that Rho is associated with the superoxide burst reaction during phagocytosis of serum- (SOZ) and IgG-opsonized zymosan particles (IOZ). In this study, we attempted to reveal the signal pathway components in the superoxide formation regulated by Rho GTPase. Tat-C3 blocked superoxide production, suggesting that RhoA is essentially involved in superoxide formation during phagocytosis of SOZ. Conversely SOZ activated both RhoA and Rac1/2. Inhibition of RhoA-activated kinase (ROCK), an important downstream effector of RhoA, by Y27632 and myosin light chain kinase (MLCK) by ML-7 abrogated superoxide production by SOZ. Extracellular signaling-regulated kinase (ERK)1/2 and p38 mitogen-activated protein kinase (MAPK) were activated during phagocytosis of SOZ, and Tat-C3 and SB203580 reduced ERK1/2 and p38 MAPK activation, suggesting that RhoA and p38 MAPK may be upstream regulators of ERK1/2. Inhibition of ERK1/2, p38 MAPK, phosphatidyl inositol 3-kinase did not block translocation of RhoA to membranes, suggesting that RhoA is upstream to these kinases. Inhibition of RhoA by Tat-C3 blocked phosphorylation of p47 PHOX. Taken together, RhoA, ROCK, p38MAPK, ERK1/2, and p47 PHOX may be subsequently activated, leading to activation of NADPH oxidase to produce superoxide.

Phagocytosis of serum-and IgG-opsonized zymos an particles induces apoptosis through superoxide but not nitric oxide in macrophage J774A.1

Phagocytosis of serum- and IgG-opsonized zymosan (SOZ and IOZ, respectively) particles into J774A.1 macrophages induced apoptosis of the cells, accompanied by the expression of p21(WAF1), one of cyclin-dependent protein kinase (CDK) inhibitors. Furthermore, phagocytosis of SOZ and IOZ particles into macophages induced superoxide formation. Tat-superoxide dismutase (SOD), which is readily transduced into the cells using Tat-domain, protected the cells from the apoptosis induced by phagocytosis of SOZ and IOZ particles. lipopolysaccharide (LPS)/interferon-gamma (IFN-gamma) also caused the apoptosis of the cells. However, Tat-SOD could not protect the cells from LPS/IFN-gamma induced apoptosis, suggesting that apoptosis mechanisms involved are different from each other. In the present study, we determined the amounts of nitric oxide (NO) produced by SOZ, IOZ, and LPS/IFN-gamma, and found that SOZ and IOZ did not induce the generation of NO in macrophages, whereas LPS/ IFN-gamma did. The apoptosis due to phagocytosis was accompanied with the release of cytochrome c from mitochondrial membrane to cytosolic fraction. Furthermore, SOZ and IOZ induced the cleavage of procasapase-3 (35 kDa) to give rise to an active caspase-3 (20 kDa), which was blocked by Tat- SOD but not by 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO), a scavenger of NO. On the other hand, LPS/IFN-gamma caused the activation of procaspase-3, which was blocked by PTIO but not by Tat-SOD. Taken together, phagocytosis of SOZ and IOZ particles induced apoptosis through superoxide but not NO in macrophages, accompanied with the release of cytochrome c and the activation of caspase-3.

Enhanced neutrophil functions by recombinant human granulocyte colony-stimulating factor in diabetic patients with foot infections in vitro

This study was performed to evaluate the effect of granulocyte-colony stimulating factor on neutrophil functions in diabetic patients with active foot infections in vitro. Twelve diabetic patients with foot infections and 12 normal volunteers were enrolled. Neutrophils from peripheral blood were incubated with granulocyte colony-stimulating factor (G-CSF, 50 ng/mL) for 20 min. Superoxide production of neutrophils was measured by the reduction of ferricytochrome C. Neutrophil phagocytosis was assayed using Staphylococcus aureus and the weighted phagocytic index was calculated. Superoxide production of neutrophils in diabetic patients with foot infections was 7.7 (unit: nmol/2 x 10(5) cells/60 min), which was significantly lower than that in controls (12.0) (p<0.05). G-CSF increased neutrophil superoxide production to 12.1 in diabetic patients with foot infections and to 19.8 in controls (p<0.05 for each). Weighted phagocytic index in diabetic patients with foot infections was 0.77, which was not significantly different from that of the controls (0.69). Weighted phagocytic index was increased significantly by G-CSF to 0.88 in diabetic patients with foot infections and to 0.79 in controls (p<0.05 for each). In conclusion, G-CSF significantly enhanced neutrophil functions in diabetic patients with foot infections in vitro.

LPS induced macrophage priming effect on O_2~ production and its signal mechanisms / 中国病理生理杂志

AIM: To investigate the effect of lipopolysaccharide (LPS) priming on macrophage(M?). METHODS: Macrophage cell line RAW264.7 were pretreated with or without LPS for 1 h, then challenged with PMA, or LPS, muramyl dipeptide(MDP), Zymosan, formyl-methionyl-leucyl-phenylalanine(FMLP) for 1 h . O  2 production in supernatants and intracellular free calcium([Ca 2+ ]i ) were measured, and changes in [Ca 2+ ]i and LPS induced O  2 production were compared. RESULTS: LPS pretreatment significantly increased O  2 production in RAW264.7 cells challenged with the stimuli, and in a certain extent, both O  2 production and increase of resting intracellular [Ca 2+ ]i were dose- and time-dependent on LPS pretreatment.Furthermore,the peak [Ca 2+ ]i was significantly higher in LPS pretreated groups than that of LPS unpretreated groups when challenged with PMA. Pretreatment with Ca 2+ inophore A23187 mimicked the LPS priming effects on O  2 production, but pretreatment with Ca 2+ chelator BAPTA and EGTA blocked this priming effect. CONCLUSION: LPS induced M? priming effect on O  2 production is dependent on elevation of resting intracellular [Ca 2+ ]i .

Protective Effect of Controlled Reperfusion with Warm Blood Cardioplegic Containing Mannitol on Mitochondrial Function after Myocardial Ischemia / 第二军医大学学报

This study tested the hypothesis that controlled reperfusion with warm blood cardioplegia containing mannitol would result in more effectively improved recovery of myocardial mitochondrial function by preventing or reducing a potentially harmful component of reperfusion. Myocardial mitochondrial function was significantly depressed after 60 min reperfusion, but slightly depressed in the controlled reperfusion group. Significantly increased MDA content and decreased SOD activity were observed after 60 min reperfusion. Hearts in the controlled reperfusion group had low MDA content and might protect the activity of SOD. The- results indicate that controlled reperfusion after ischemia provides benefit in avoiding myocardial mitochondrial reperfusion injury.