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1.
J Med Chem ; 40(4): 559-73, 1997 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-9046347

RESUMO

A series of 2,3-dihydro-5-benzofuranamines (5-aminocoumarans) were developed for the treatment of traumatic and ischemic central nervous system (CNS) injury. Compounds within this class were extremely effective inhibitors of lipid peroxidation in vitro and antagonized excitatory behavior coupled with peroxidative injury induced by spinal intrathecal injection of FeCl2 (mouse-FeCl2-it assay) in vivo. Selected compounds were tested for antagonistic activity on methamphetamine (MAP)-induced hypermotility resulting from dopamine release in the mouse brain. Among the compounds synthesized, compound 26n (2,3-dihydro-2,4,6,7-tetramethyl-2-[(4-phenyl-1-piperidinyl) methyl]-5-benzofuranamine) exhibited potent effects in these assays (inhibition of lipid peroxidation, IC50 = 0.07 microM; mouse-FeCl2-it assay, ID50 = 10.4 mg/ kg, po; MAP-induced hypermotility, 98% inhibition, 10 mg/kg, ip). The S-(+)-form of compound 26n dihydrochloride (TAK-218), which has 30 times more potent antagonistic activity on MAP-induced hypermotility than the R-(-)-form, improved more significantly the survival rate in the cerebral ischemia model (rat, 1-3 mg/kg, ip) during the period of 1-14 days after ischemia and decreased functional disorders in the traumatic brain injury model (rat, 0.1-1 mg/kg, ip) 3-14 days after injury. These results imply a role for dopamine in deterioration of CNS function after ischemic and traumatic injury. TAK-218 is a promising compound for the treatment of stroke and CNS trauma and is now under clinical investigation.


Assuntos
Benzofuranos/química , Benzofuranos/farmacologia , Sistema Nervoso Central/lesões , Dopamina/metabolismo , Peróxidos Lipídicos/metabolismo , Animais , Isquemia Encefálica/tratamento farmacológico , Sistema Nervoso Central/irrigação sanguínea , Compostos Ferrosos/farmacologia , Isomerismo , Masculino , Camundongos , Microssomos Hepáticos/metabolismo , Ratos , Ratos Wistar
2.
Shock ; 10(4): 278-84, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9788660

RESUMO

Effects of growth hormone (GH) and insulin-like growth factor (IGF)-I on bactericidal capacity of human polymorphonuclear neutrophils (PMNs) were investigated. Venous blood was collected from healthy volunteers. In Experiment 1, PMNs were isolated, incubated with GH or IGF-I, and cocultured with Escherichia coli. E. coli-killing capacity, viability, and CD11b and CD16 expressions of PMNs were then assessed. Both GH and IGF-I enhanced E. coli killing by PMNs. GH preserved PMN viability during E. coli killing, whereas IGF-I enhanced PMN CD11b expression before coculture with E. coli. In Experiment 2, whole blood was washed and incubated with GH or IGF-I. PMNs in washed whole blood were then analyzed for phorbol myristate acetate (PMA)-stimulated CD11b, CD35, and CD16 expressions and production of reactive oxygen intermediates (ROI), as well as phagocytosis with/without anti-CD11b antibody. IGF-I enhanced PMN expressions of CD11b and CD35, but not CD16, stimulated with PMA. Both hormones enhanced phagocytosis, which was abrogated by anti-CD11b antibody, and intracellular ROI production by PMNs. These results indicate that both GH and IGF-I augment human PMN bactericidal capacity, via increased phagocytosis and intracellular ROI production. Preservation of PMN viability by GH and enhanced complement receptor expression by IGF-I may also be associated with augmented PMN bactericidal capacity. Although PMN activation has potentially harmful aspects, these results encourage additional studies to confirm the clinical relevance of exogenous GH or IGF-I for the prevention or management of septic complications in perioperative or critically ill patients especially with low circulating GH and/or IGF-I levels.


Assuntos
Hormônio do Crescimento Humano/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Neutrófilos/microbiologia , Neutrófilos/fisiologia , Sobrevivência Celular , Células Cultivadas , Técnicas de Cocultura , Relação Dose-Resposta a Droga , Escherichia coli , Humanos , Antígeno de Macrófago 1/metabolismo , Neutrófilos/efeitos dos fármacos , Fagocitose , Espécies Reativas de Oxigênio/metabolismo , Receptores de Complemento 3b , Receptores de IgG/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
3.
Shock ; 15(4): 318-22, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11303733

RESUMO

Total parenteral nutrition (TPN) decreases intestinal IgA and levels of Th2 cytokines, interleukin (IL)-4, and IL-10 within the supernatants of intestinal homogenates. These cytokines are known to stimulate IgA production in vitro by cells of the gut-associated lymphoid tissue (GALT). Glutamine (GLN) supplementation of TPN normalizes GALT mass and cytokine levels. Because intestinal homogenates contain mucosa which itself is a source of cytokines, it was unclear whether cytokines change within the GALT itself. This study investigates dietary effects on IL-4 and IL-10 cytokine mRNA expression within isolated GALT lamina propria cells after lipopolysaccharide (LPS) stimulation. Prospective randomized experimental trials were used in this study. Fifty-nine mice were randomized to chow, intravenous TPN (IV-TPN), intragastric TPN (IG-TPN), complex enteral diet (CED), or 2% GLN-supplemented TPN (GLN-TPN). In experiment 1, animals were fed chow, IV-TPN, IG-TPN, or CED for 5 days and received intraperitoneal LPS (100 microg/kg BW), and then were sacrificed 1 h later. Intestine was harvested for GALT lamina propria. Total RNA was extracted from lamina propria cells and cytokine mRNA for IL-4, and IL-10 was measured by reverse transcriptase polymerase chain reaction. IgA levels of intestinal washing were also measured with ELISA. In experiment 2, mRNA for IL-4 and IL-10, and intestinal IgA levels were measured in mice fed chow, IV-TPN, or GLN-TPN as in experiment 1. Both IL-4 and IL-10 mRNA expression decreased significantly in IV-TPN mice compared to chow or CED feeding. IG-TPN resulted in IL-10 mRNA expression significantly lower than chow or CED but significantly better than IV-TPN. GLN preserved IL-4 and IL-10 mRNA levels, which correlated with intestinal IgA levels. Route and type of nutrition as well as GLN influence message for the Th2 type IgA-stimulating cytokines, IL-4 and IL-10, within the primary site of GALT IgA production, the lamina propria.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Glutamina/uso terapêutico , Interleucina-10/genética , Interleucina-4/genética , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Lipopolissacarídeos/farmacologia , Tecido Linfoide/metabolismo , Nutrição Parenteral Total/efeitos adversos , RNA Mensageiro/biossíntese , Ração Animal , Animais , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Gastrostomia , Glutamina/farmacologia , Imunoglobulina A/biossíntese , Imunoglobulina A/genética , Interleucina-10/biossíntese , Interleucina-4/biossíntese , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/imunologia , Laparotomia , Tecido Linfoide/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Redução de Peso
4.
Shock ; 13(4): 274-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10774615

RESUMO

The energy source for neutrophils (PMNs) has long been believed to be glucose. However, it has been shown recently that PMNs use glutamine as well as glucose. Nevertheless, the comparative effects of glucose and glutamine on PMN function remain to be clarified. This study investigated the relative effects of glucose and glutamine on reactive oxygen intermediate (ROI) production by PMNs. In experiment 1, PMNs (1 x 10(6)/mL) isolated from healthy volunteers were incubated in RPMI 1640 medium containing neither glucose nor glutamine for 4, 12, 18, and 24 h at 37 degrees C. The medium was supplemented with 0 or 200 mg/dL (0 or 11 mM, respectively) glucose and glutamine (0, 0.5, 1, or 2 mM). PMN cell death was assessed on the basis of hypodiploid DNA by flow cytometry using propidium iodide DNA staining. ROI production by PMNs was determined by flow cytometry using dihydrorhodamine 123. In experiment 2, isolated PMNs were cultured in RPMI 1640 medium containing neither glucose nor glutamine. The medium was supplemented with glucose (0 or 11 mM) and a competitive inhibitor of glycolysis, 2-deoxy-D-glucose (2-DG; 0 or 20 mM). Each medium was supplemented with glutamine (0, 0.5, 1, or 2 mM) and incubated for 12 h at 37 degrees C. Then, ROI production by PMNs was measured. PMN cell death was not affected by glucose or glutamine in this experiment. In contrast, ROI production by PMNs was greater at 11 mM glucose than at 0 mM glucose at all incubation times studied. At 11 mM glucose, supplemental glutamine enhanced PMN ROI production after 18 and 24 h culture. In contrast, at 0 mM glucose, glutamine augmented ROI production by PMNs after 12 h as well as with 18 and 24 h incubations. PMN ROI production after 12 h culture was significantly greater at 11 mM glucose without 2-DG than at both 11 and 0 mM glucose with addition of 2-DG. In addition, supplemental glutamine enhanced ROI production by PMNs when 2-DG was added at 11 and 0 mM glucose. Glucose is essential for PMN ROI production. Under conditions of glucose depletion in vitro, glutamine is of importance in ROI production by PMNs, whereas the enhancing effect of glutamine on PMN ROI production is minor compared to that of glucose.


Assuntos
Glucose/farmacologia , Glutamina/farmacologia , Neutrófilos/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Células Cultivadas , Desoxiglucose/farmacologia , Diploide , Humanos , Cinética , Neutrófilos/efeitos dos fármacos , Valores de Referência
5.
Shock ; 6(5): 345-50, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8946650

RESUMO

Effects of growth hormone (GH) and insulin-like growth factor (IGF)-I on Escherichia coli-killing activity of murine peritoneal exudative cells (PECs) were investigated. Plasma from the mice, injected subcutaneously with saline, GH (4.8 mg/kg/day), or IGF-I(24 mg/kg/day) for 6 days, was mixed with E. coli and pooled murine PECs. Plasma from GH- and IGF-I-treated mice modestly but significantly augmented the E. coli-killing activity of PECs, as compared with that from saline controls. Plasma from IGF-I-treated mice also enhanced PEC interleukin 1 production. In the next experiment, PECs preincubated with medium, GH (10-1000 ng/mL), or IGF-I (50-5000 ng/mL) for 3 h were investigated for E. coli-killing activity. Preincubation of PECs with all concentrations of GH and IGF-I significantly enhanced the E. coli-killing activity of PECs, as compared with the medium control. These results indicate that GH and IGF-I enhance phagocytosis and the E. coli-killing activity of PECs, via a modestly increased plasma capacity to support these activities, as well as by a strong direct action.


Assuntos
Escherichia coli/efeitos dos fármacos , Exsudatos e Transudatos/fisiologia , Hormônio do Crescimento/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Cavidade Peritoneal/citologia , Animais , Atividade Bactericida do Sangue/efeitos dos fármacos , Caseínas/farmacologia , Citocinas/metabolismo , Exsudatos e Transudatos/efeitos dos fármacos , Feminino , Hormônio do Crescimento/sangue , Camundongos , Camundongos Endogâmicos BALB C , Cavidade Peritoneal/microbiologia , Hidrolisados de Proteína/farmacologia
6.
Shock ; 16(2): 143-7, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11508867

RESUMO

Neutrophil adhesion to the pulmonary endothelium is prerequisite to neutrophil transmigration and activation, both of which may lead to lung injury. A simple method to evaluate neutrophil adherence in the lung would be useful for developing new strategies for neutrophil-mediated lung injury. The purpose was to establish a simple method to evaluate neutrophil adhesion in the lung using ex vivo fluorescence microscopy. Rats were anesthetized, and the right jugular veins were catheterized. Neutrophils were isolated from another set of rats and labeled with 5,(6)-carboxyfluorescein diacetate. Animals were killed 120 s after a 1 x 10(6) labeled neutrophil injection. The pulmonary labeled neutrophil number was counted under a fluorescence microscope. In the first experiment, rats were given 0, 20, 200, or 2000 microg/kg lipopolysaccharide (LPS) i.p. At 4 h after challenge, the pulmonary labeled neutrophil number was determined. Kinetic studies were also performed at 0, 1, 4, and 8 h after 200 microg/kg LPS. Finally, anti-ICAM-1 Ab was injected i.v. before LPS 200 microg/kg, and the labeled neutrophil number in the lung was determined at 4 h. The number of pulmonary labeled neutrophils was higher after LPS 200 or 2000 microg/kg than after the other doses. The pulmonary labeled neutrophil number was increased at 4 h compared with the other time points. ICAM-1 blocking normalized the pulmonary labeled neutrophil number in the LPS group. In conclusion, our method seems to reflect ICAM-1-mediated neutrophil adherence to the endothelium in the present setting. This simple technique may be useful for evaluating neutrophil adhesion.


Assuntos
Endotélio Vascular/fisiologia , Pulmão/fisiologia , Neutrófilos/fisiologia , Circulação Pulmonar/fisiologia , Animais , Adesão Celular/fisiologia , Endotélio Vascular/citologia , Escherichia coli , Técnicas In Vitro , Molécula 1 de Adesão Intercelular/imunologia , Contagem de Leucócitos , Lipopolissacarídeos/toxicidade , Masculino , Microscopia de Fluorescência/métodos , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Análise de Regressão
7.
Shock ; 15(1): 24-8, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11198353

RESUMO

The gut primes neutrophils (PMNs) during injury, which can then induce distant organ damage after a second insult. ICAM-1 is an important adhesion molecule in PMN attachment to the vascular endothelium. Parenteral nutrition (TPN) decreases gut levels of interleukin (IL)-4 and IL-10, two cytokines that are normal inhibitors of ICAM-1 expression. TPN also increases gut ICAM-1 expression and PMN accumulation. Since glutamine (GLN) and bombesin (BBS) prevent TPN-associated impairment of mucosal immunity, we hypothesized that GLN and BBS would modulate organ ICAM-1 expression in association with normalization of IL-4 and IL-10 levels. Forty-four mice were fed chow, TPN, or GLN-TPN (isonitrogenous 2% GLN-enriched TPN). After 5 days of diets, ICAM-1 expression was quantified in organs using the dual radiolabeled monoclonal antibody technique. In the next experiment, 29 mice were fed chow, TPN, or BBS-TPN (BBS 15 microg/kg TID) for 5 days to measure organ ICAM-1 expression. Total IL-4 and IL-10 levels were measured with ELISA from intestinal homogenates of another set of 52 mice fed chow, TPN, GLN-TPN, or BBS-TPN. TPN significantly increased ICAM-1 expression in the lung, kidney, and intestine compared with chow mice. GLN-TPN decreased intestinal, but not lung, ICAM-1 expression, while BBS-TPN reduced pulmonary, but not gut, ICAM-1 levels. GLN- and BBS-TPN returned gut IL-4 levels to normal, but failed to increase IL-10 levels. GLN and BBS had different effects on organ ICAM-1 expression induced by lack of enteral nutrition. Mechanisms other than recovery of IL-4 alone may be responsible for gut ICAM-1 expression.


Assuntos
Bombesina/farmacologia , Glutamina/farmacologia , Molécula 1 de Adesão Intercelular/efeitos dos fármacos , Molécula 1 de Adesão Intercelular/metabolismo , Nutrição Parenteral , Animais , Peso Corporal/efeitos dos fármacos , Interleucina-10/metabolismo , Interleucina-4/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo
8.
Shock ; 12(5): 365-72, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10565611

RESUMO

This study was designed to investigate how live Escherichia coli influence the fate of polymorphonuclear neutrophils (PMNs) in vitro. PMNs from 10 healthy volunteers were cocultured with or without live E. coli at different ratios. Heat-killed E. coli (Hk) were also added to PMNs at a ratio of 1:10. The PMNs were then analyzed by flow cytometry for cell death, reactive oxygen intermediates (ROI) production, and CD16 expression. Morphologic features were also assessed. PMN apoptosis was confirmed by DNA gel electrophoresis. Low doses of E. coli (PMN:E. coli ratios of 1:0.01 and 1:0.1) inhibited PMN apoptosis. In contrast, a high dose of E. coli (PMN:E. coli ratio of 1:10) increased PMN necrosis. ROI production was significantly greater at PMN:E. coli ratios of 1:10 and 1:10 (Hk) than at ratios of 1:0.01 and 1:0.1, or in PMNs cultured alone after a 15 or 30 minute coculture. CD16 expressions were significantly lower in PMNs cocultured with E. coli than in those cultured alone after a 4 or 12-h coculture. Tumor necrosis factor-alpha, interleukin (IL)-1beta and IL-6 levels in cell-free supernatants were also measured. The mean percentages of apoptosis at PMN:E. coli ratios of 1:0.01 and 1:10 (Hk), and in PMNs cultured alone after a 12-h coculture showed significant inverse correlations with these cytokine levels in cell-free supernatants at 12 h. Our results demonstrate that low doses of live E. coli inhibits predominantly PMN apoptosis, whereas a high dose of E. coli increases necrosis. Augmented PMN bactericidal function, via inhibition of PMN cell death, may be beneficial for host defense against bacterial infection and/or sepsis.


Assuntos
Citocinas/metabolismo , Escherichia coli/patogenicidade , Neutrófilos/imunologia , Apoptose , Contagem de Células Sanguíneas , Morte Celular/fisiologia , Sistema Livre de Células , Contagem de Colônia Microbiana , Fragmentação do DNA , Diploide , Humanos , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Necrose , Neutrófilos/microbiologia , Neutrófilos/patologia , Espécies Reativas de Oxigênio/metabolismo , Receptores de IgG/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
9.
Surgery ; 129(1): 76-85, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11150036

RESUMO

BACKGROUND: The fate of exudative polymorphonuclear neutrophils (PMNs) at the local site after surgery is not well understood. We evaluated the fate and functions of exudative PMNs at the local site in patients who were undergoing major surgery. We also investigated the relation between PMN apoptosis and cytokine levels at the local site during the postoperative period. METHODS: Exudative PMNs were isolated from 11 patients during the postoperative period. Apoptosis, reactive oxygen intermediates (ROI) production, CD16, and tumor necrosis factor receptor expression of the PMNs were determined by flow cytometry. Cytokine levels in the drainage fluid were measured. RESULTS: Exudative PMN apoptosis was markedly inhibited on postoperative day 1 and then increased in a time-dependent manner. IL-6 and granulocyte macrophage colony-stimulating factor were significant factors to inhibit exudative PMN apoptosis; tumor necrosis factor-alpha and IL-10 were the factors to increase apoptosis. ROI production and CD16 expression of exudative PMNs were augmented when PMN apoptosis was inhibited in the early postoperative period. CONCLUSIONS: Exudative PMN apoptosis was inhibited after surgery; PMN function was augmented after surgery. Cytokines at the local site may modulate exudative PMN apoptosis. Exudative PMN apoptosis reflected the inflammatory response after surgery. Understanding the mechanisms of PMN apoptosis and its pathophysiologic significance at local inflammatory sites in vivo may help in the design of more rational treatments.


Assuntos
Apoptose/imunologia , Citocinas/metabolismo , Inflamação/imunologia , Inflamação/patologia , Neutrófilos/citologia , Neutrófilos/imunologia , Complicações Pós-Operatórias/imunologia , Complicações Pós-Operatórias/patologia , Idoso , Idoso de 80 Anos ou mais , Citocinas/sangue , Exsudatos e Transudatos/citologia , Exsudatos e Transudatos/imunologia , Humanos , Inflamação/etiologia , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Ploidias , Complicações Pós-Operatórias/etiologia , Espécies Reativas de Oxigênio/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Fatores de Tempo
10.
Arch Surg ; 130(4): 410-4, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7710342

RESUMO

OBJECTIVE: To examine the effects of a nitric oxide synthase inhibitor on host elimination of bacteria, tumor necrosis factor (TNF) production, and survival in a murine sepsis model. DESIGN: Prospective randomized experimental trials. SETTING: Laboratory. MATERIALS: Female Balb/c mice. INTERVENTIONS: Balb/c mice were injected with Escherichia coli (10(8) colony-forming units per body) into the peritoneal cavity. N-omega-Nitro-L-arginine-methyl-ester (L-NAME), an inhibitor of nitric oxide synthase, was given intraperitoneally at 10 mg/kg (N10 group) or 100 mg/kg (N100 group) 1 hour before bacterial challenge. MAIN OUTCOME MEASURES: Thirty animals were observed for survival. Samples of peritoneal lavaged fluid (PLF), blood, liver, and lungs were obtained at 4 and 6 hours after bacterial challenge (n = 60). The peritoneal exudative cells were counted. Viable bacterial counts were determined in PLF, blood, and organs. The TNF levels also were determined in plasma, PLF, and supernatant samples of cultured peritoneal exudative cells. RESULTS: Survival times after E coli challenge were significantly reduced by pretreatment with L-NAME (100 mg/kg intraperitoneally). Numbers of viable bacteria in the peritoneal cavity and plasma TNF level 4 hours after E coli challenge were higher in both L-NAME-treated groups than in the control group. The number of bacteria in the blood and the plasma TNF level 6 hours after E coli challenge were higher in the L-NAME-treated group (N100 group) than in the control group. Conversely, the number of hepatic bacteria in the control group was significantly higher than in the L-NAME-treated groups. Plasma TNF level showed significant positive correlations with numbers of bacteria in the PLF and in the blood 4 hours after challenge. No significant differences were noted in TNF levels in PLF and peritoneal exudative cell cultured supernatants. CONCLUSION: Inhibition of nitric oxide production is detrimental in this gram-negative sepsis model.


Assuntos
Arginina/análogos & derivados , Infecções por Escherichia coli/tratamento farmacológico , Óxido Nítrico/antagonistas & inibidores , Sepse/tratamento farmacológico , Animais , Arginina/efeitos adversos , Arginina/uso terapêutico , Escherichia coli/crescimento & desenvolvimento , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/mortalidade , Feminino , Camundongos , Camundongos Endogâmicos BALB C , NG-Nitroarginina Metil Éster , Lavagem Peritoneal , Peritônio/citologia , Distribuição Aleatória , Sepse/microbiologia , Sepse/mortalidade , Taxa de Sobrevida , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/efeitos dos fármacos
11.
Arch Surg ; 130(10): 1115-22, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7575126

RESUMO

OBJECTIVE: To investigate the effects of exogenous growth hormone (GH) and insulinlike growth factor I (IGF-I) on host defense and survival in a murine model of Escherichia coli sepsis. DESIGN: Prospective randomized experimental trials. SETTING: Laboratory. MATERIALS: Nine-week-old female BALB/c mice. INTERVENTIONS: Mice were injected subcutaneously with 4.8 or 0.48 mg/kg of body weight per day of GH, 24 or 2.4 mg/kg of body weight per day of IGF-I or, as a control, normal saline solution, for 6 days. Mice were then challenged intraperitoneally with 1 x 10(8) colony-forming units per body of E coli. MAIN OUTCOME MEASURES: Fifty mice were observed for survival. In the next experiments, samples from the high-dose GH, high-dose IGF-I, and saline control groups were harvested before or at 4 or 6 hours after challenge. Numbers of peritoneal exudative cells and tissue-viable bacterial counts were determined. Peritoneal exudative cells were cultured with lipopolysaccharide (10 micrograms/mL) for 24 hours. Levels of tumor necrosis factor, interleukin-1, and interleukin-6 in the peritoneal lavage fluid, plasma and supernatants of peritoneal exudative cell culture were measured. RESULTS: Both high and low doses of GH and high-dose IGF-I significantly prolonged survival. Growth hormone and IGF-I significantly increased peritoneal exudative cell numbers and reduced viable bacterial counts in the peritoneal lavage fluid and the liver. These hormones significantly suppressed excessive systemic cytokine production, while enhancing in vitro cytokine production and preserving local cytokine responses. CONCLUSION: The immunomodulation produced by administration of GH or IGF-I leads to improved host defense in this murine model of E coli sepsis.


Assuntos
Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/terapia , Hormônio do Crescimento/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Análise de Variância , Animais , Líquido Ascítico/química , Líquido Ascítico/citologia , Líquido Ascítico/microbiologia , Sangue/microbiologia , Células Cultivadas , Feminino , Hormônio do Crescimento/uso terapêutico , Imunoterapia , Injeções Subcutâneas , Fator de Crescimento Insulin-Like I/uso terapêutico , Interleucina-1/análise , Interleucina-6/análise , Fígado/microbiologia , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Estudos Prospectivos , Distribuição Aleatória , Análise de Regressão , Fator de Necrose Tumoral alfa/análise
12.
Arch Surg ; 136(3): 297-304, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11231849

RESUMO

HYPOTHESIS: Patients with malnutrition are susceptible to infection. Polymorphonuclear neutrophils (PMNs) are the major effector of the nonspecific immune response in host resistance to infection. Dietary restriction may impair PMN-mediated immunity in the peritoneal cavity by reducing PMN exudation, adhesion molecule expression on PMNs, and chemokine production. DESIGN: Randomized study of murine glycogen-induced peritonitis with dietary restriction. SETTING: University research laboratory. MATERIALS: Male C57BL/6J mice. INTERVENTIONS: Mice (N = 204) were assigned to ad libitum, moderate, and severe diet-restricted groups receiving mouse chow ad libitum (132 g/kg, 66 g/kg, and 33 g/kg daily for 7 days, respectively). After dietary restriction with or without 1 day of refeeding, mice were administered glycogen intraperitoneally to induce cell exudation. MAIN OUTCOME MEASURES: CD11b, CD18, and CD62L expressions on circulating PMNs, phagocytosis, and reactive oxygen intermediate production by exudative PMNs were measured after glycogen installation. The levels of PMN-specific chemokine, macrophage inflammatory protein 2 (MIP-2), in peritoneal lavage fluid were also measured. These parameters were measured after glycogen installation in the refeeding experiment. RESULTS: Seven days of dietary restriction decreased CD11b/CD18 expression on circulating PMNs, MIP-2 levels in peritoneal lavage fluid, and subsequent PMN exudation into the peritoneal cavity early in peritonitis. Both CD11b and CD18 expression on circulating PMNs and MIP-2 levels correlated significantly with numbers of exudative PMNs. Seven days of dietary restriction also impaired phagocytosis, while up-regulating reactive oxygen intermediate production by exudative PMNs. Only 1 day of ad libitum refeeding normalized CD11b/CD18 expression with PMN exudation into the peritoneal cavity. CONCLUSIONS: Short-term dietary restriction impairs PMN exudation into local inflammatory sites in murine peritonitis by reducing CD11b/CD18 expression and MIP-2 production. Even brief nutritional replenishment in diet-restricted patients may improve host defense via restoring these PMN functions and chemokine production at local inflammatory sites.


Assuntos
Antígenos CD18/metabolismo , Quimiocinas/metabolismo , Antígeno de Macrófago 1/metabolismo , Neutrófilos/imunologia , Peritonite/imunologia , Inanição/imunologia , Animais , Quimiocina CXCL2 , Glicogênio , Tolerância Imunológica/imunologia , Selectina L/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Lavagem Peritoneal , Peritonite/induzido quimicamente , Fagocitose/imunologia
13.
Arch Surg ; 132(12): 1320-5, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9403537

RESUMO

OBJECTIVE: To clarify how antibiotic prophylaxis influenced an outbreak of methicillin-resistant Staphylococcus aureus (MRSA) and postoperative infection. DESIGN: Retrospective review. SETTING: University-affiliated teaching hospital. PATIENTS: All patients (n=1824) undergoing subtotal esophagectomy, gastrectomy, or colorectal surgery during the period 1982 through 1995. MAIN OUTCOME MEASURES: Type, timing, and duration of prophylactic antibiotics. Postoperative infection by the Centers for Disease Control and Prevention definition and the organisms isolated. RESULTS: Third-generation cephalosporins were frequently administered for prophylaxis during the period 1982 through 1990. The rate of isolates of MRSA from the infected site increased, peaking in 1988 to 1990. Since 1991 to 1992, along with a marked decrease in third-generation cephalosporin use, the rates of MRSA isolated have declined dramatically. The timing of administration changed from postoperative to intraoperative. Although the duration was gradually decreased, coverage was still provided until about the fifth postoperative day, even during 1993 to 1995. Prolonged coverage did not reduce the rate of superficial incisional or organ/space surgical site infection or that of pneumonia. CONCLUSIONS: Overuse of third-generation cephalosporins for long periods caused an MRSA outbreak. Long-term prophylaxis did not lower infection rates. The briefest possible prophylaxis with first- or second-generation cephalosporins should be used in general surgery.


Assuntos
Antibioticoprofilaxia , Resistência a Meticilina , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/efeitos dos fármacos , Infecção da Ferida Cirúrgica/prevenção & controle , Cefalosporinas/administração & dosagem , Cefalosporinas/uso terapêutico , Colo/cirurgia , Esofagectomia , Gastrectomia , Humanos , Enteropatias/cirurgia , Reto/cirurgia , Estudos Retrospectivos , Infecções Estafilocócicas/tratamento farmacológico
14.
Arch Surg ; 134(10): 1055-60, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10522845

RESUMO

HYPOTHESIS: The levels of intestinal interleukin 10 and interleukin 4, inhibitors of intercellular adhesion molecule-1 (ICAM-1) expression, decline with total parenteral nutrition (TPN). These cytokine changes induced by lack of enteral nutrition may increase ICAM-1 expression, resulting in polymorphonuclear neutrophil accumulation in intestine. DESIGN: Prospective randomized experimental trials. SETTING: Laboratory. MATERIALS: Male mice. INTERVENTIONS: Sixty-three mice were randomized to chow, intravenous TPN, or intragastric TPN. MAIN OUTCOME MEASURES: Experiment 1: After diet manipulation, iodine 125-labeled anti-ICAM-1 antibody and iodine 131-labeled nonbinding antibody were injected to quantify ICAM-1 expression on endothelial cells in the lung, liver, kidney, and small intestine. Measurement of myeloperoxidase was used to quantify polymorphonuclear neutrophil accumulation in the organs. Experiment 2: Intestine was harvested for both ICAM-1 and myeloperoxidase levels after chow refeeding of mice in the intravenous TPN group. RESULTS: In experiment 1, uninjured mice fed intravenous TPN showed significantly increased intestinal ICAM-1 expression and polymorphonuclear neutrophil accumulation with no significant changes in the lung, liver, or kidney. No changes occurred in mice fed chow or intragastric TPN. In experiment 2, reinstitution of enteral feeding returned intestinal ICAM-1 and myeloperoxidase levels to normal. CONCLUSION: Gut changes associated with lack of enteral feeding induce endothelial changes and an immunologic response, which may influence subsequent responses to injury.


Assuntos
Molécula 1 de Adesão Intercelular/biossíntese , Intestino Delgado/imunologia , Neutrófilos/metabolismo , Nutrição Parenteral Total , Animais , Masculino , Camundongos , Camundongos Endogâmicos ICR , Distribuição Aleatória
15.
Arch Surg ; 135(10): 1177-82, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11030875

RESUMO

HYPOTHESIS: Intravenous total parenteral nutrition (TPN) induces intestinal polymorphonuclear neutrophil recruitment with increased intestinal intercellular adhesion molecule-1 expression. While intercellular adhesion molecule-1 causes firm adhesion of leukocytes to the endothelial cells, P- and E-selectin mediate leukocyte recruitment via rolling. Therefore, manipulation of nutrition may also affect P- and E-selectin expression in organs. DESIGN: Prospective randomized experimental trials. SETTING: Laboratory. MATERIALS: Male mice. INTERVENTIONS: Fifty-three mice were randomized to chow, intravenous TPN, or intragastric TPN. MAIN OUTCOME MEASURES: After 5 days of diet, mice were administered iodine 125-labeled anti-P-selectin antibody (or iodine 125-labeled anti-E-selectin antibody) and iodine 131-labeled nonbinding antibody to quantify P-selectin (or E-selectin) expression in organs (lung, liver, kidney, small intestine, colon, stomach, pancreas, mesentery, heart, and skeletal muscle). RESULTS: P-selectin in small intestine, colon, stomach, and pancreas in the intravenous TPN group increased significantly as compared with the chow and the intragastric TPN groups. E-selectin expression was up-regulated after intravenous TPN in the lung but not in other sites. CONCLUSIONS: In a time frame (5 days) when intercellular adhesion molecule-1 expression and neutrophil recruitment are increased, intestinal expression of P-selectin remains up-regulated. Early lung inflammatory changes are reflected by increases in E-selectin. This change may reflect early pulmonary dysfunction with intravenous TPN, but its significance requires further study.


Assuntos
Molécula 1 de Adesão Intercelular/biossíntese , Intestino Grosso/metabolismo , Intestino Delgado/metabolismo , Selectina-P/biossíntese , Nutrição Parenteral Total , Análise de Variância , Animais , Dieta , Infusões Intravenosas , Molécula 1 de Adesão Intercelular/análise , Pulmão/metabolismo , Masculino , Camundongos , Modelos Animais , Selectina-P/análise , Probabilidade , Distribuição Aleatória , Valores de Referência
16.
J Am Coll Surg ; 183(5): 450-6, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8912613

RESUMO

BACKGROUND: Peritonitis remains a major infectious problem. Neutrophil influx into the peritoneal cavity is one of the most important host defense mechanisms. However, no studies have focused on the site of neutrophil exudation. This study examined the primary anatomic site of neutrophil exudation in bacterial peritonitis. STUDY DESIGN: Fifty-five rats were injected intraperitoneally with saline solution (control group) or 10(7) Escherichia coli (peritonitis group). In experiment 1, 1 x 10(6) fluorescein-labeled neutrophils were infused 3 hours after the challenge. Then, peritoneal-lavaged fluids and peritoneal tissues (the greater omentum, mesentery, parietal peritoneum, colon, and ileum) were obtained. Subpopulations of peritoneal exudative cells and numbers of labeled neutrophils in tissues were counted. In experiment 2, labeled neutrophils were infused at 10 minutes and at 1 and 5 hours after the challenge. Peritoneal tissues were also harvested. The number of labeled neutrophils in each tissue was determined. RESULTS: In experiment 1, numbers of labeled peritoneal neutrophils and exudative neutrophils were higher in the peritonitis group than in the control group. Numbers of exudative neutrophils showed a positive correlation with numbers of labeled peritoneal neutrophil. In experiment 2, at 1 and 5 hours after the challenge, the number of labeled neutrophils was higher in the peritonitis group than in the control group. The number of neutrophils in the omentum was higher than the number in other peritoneal tissues. CONCLUSIONS: Our fluorescence microscopic method is useful for detecting neutrophil adhesion. Neutrophil exudation into the peritoneal cavity was most marked in the omentum. The greater omentum may play an important role in host defense as a source of exudative neutrophils.


Assuntos
Infecções por Escherichia coli/imunologia , Neutrófilos/imunologia , Omento/fisiologia , Peritonite/imunologia , Animais , Adesão Celular , Exsudatos e Transudatos , Fluoresceínas , Microscopia de Fluorescência , Peritonite/microbiologia , Fagocitose , Ratos , Ratos Sprague-Dawley
17.
Clin Nutr ; 15(6): 321-5, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16844065

RESUMO

The growth hormone (GH)-insulin-like growth factor 1 (IGF-1) axis is impaired in liver cirrhosis. We determined the effects of GH and IGF-1 treatments in gastrectomized rats with thioacetamide-induced cirrhosis. GH did not increase hepatic IGF-1-mRNA, plasma IGF-1 or the tissue, i.e. gastrocnemius muscle IGF-1 level. IGF-1 administration increased plasma IGF-1 without increasing hepatic IGF-1-mRNA. GH and IGF-1 independently decreased postoperative urinary nitrogen excretion. We conclude that both GH and IGF-1 improve postoperative nitrogen metabolism. Furthermore, GH may exert its anabolic effects directly and/or via actions mediated by IGF-1 production, other than in the liver and in the skeletal muscle, in the setting of cirrhosis.

18.
Int J Radiat Biol ; 79(5): 359-66, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12943244

RESUMO

PURPOSE: To elucidate the brain molecular response to irradiation. The expression of the intercellular adhesion molecule (ICAM-1) and tumour necrosis factor-alpha (TNF-alpha) in the mouse brain was compared after single-dose and fractionated whole-brain irradiation. MATERIALS AND METHODS: Mice received a single dose of 2, 10 or 20 Gy or a fractionated dose (2 Gy day(-1)) of 10, 20 or 40 Gy. ICAM-1, and TNF-alpha mRNA expression were quantified by the highly sensitive real-time polymerase chain reaction technique. Expression of ICAM-1 protein was quantified by dual-labelled monoclonal antibody assay. RESULTS: After a 20-Gy single dose, there was an increase in ICAM-1 and TNF-alpha mRNA levels (14- and 11-fold, respectively) as well as a significant increase in the level of ICAM-1 protein (p=0.0243). The expression of ICAM-1 and TNF-alpha mRNA increased at the end of the 40-Gy fractionated regimen (3.55- and 2.30-fold, respectively). CONCLUSIONS: The molecular response of the brain to single-dose irradiation was rapid, while its response to fractionated irradiation was slow. This finding is consistent with clinical observations and could be of use when designing strategies to mitigate radiation sequelae.


Assuntos
Encéfalo/metabolismo , Encéfalo/efeitos da radiação , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Animais , Sequência de Bases , Fracionamento da Dose de Radiação , Expressão Gênica/efeitos da radiação , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
19.
Nutrition ; 16(5): 323-9, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10793298

RESUMO

The energy substrate for neutrophils has been believed to be glucose. However, a recent investigation has demonstrated that neutrophils use glutamine (Gln) as well as glucose. Nevertheless, little is known about the effects of Gln on neutrophil function. Thus, this study was designed to investigate the effects of Gln on phagocytosis and reactive oxygen intermediate (ROI) production by neutrophils from postoperative patients in vitro. Eleven patients who had undergone major gastrointestinal surgery were randomly selected. Peripheral blood was drawn before surgery and on postoperative days (PODs) 1, 3, and 7. The blood was washed with medium to remove plasma. Washed whole blood was incubated in RPMI 1640 medium containing neither Gln nor glucose for 24 h at 37 degrees C. The medium was supplemented with Gln at a concentration of 0, 500, 1000, or 2000 microM. Whole blood was then assessed for phagocytosis by flow cytometry using fluorescent beads. ROI production by phagocytes was measured by flow cytometry using dihydrorhodamine 123. In each assay, the neutrophil population was gated and analyzed. Serum amino acids were also measured. Postoperative serum Gln level decreased significantly until POD 7. Phagocytosis by neutrophils on PODs 3 and 7 was significantly greater at 2000 microM Gln than at other Gln concentrations. Neutrophil ROI production was significantly greater at 2000 microM Gln than at 0 microM Gln at each time point. In conclusion, supplemental Gln enhances both phagocytosis and ROI production by neutrophils from postoperative patients in vitro.


Assuntos
Suplementos Nutricionais , Glutamina/farmacologia , Monócitos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Idoso , Idoso de 80 Anos ou mais , Neoplasias Esofágicas/cirurgia , Feminino , Citometria de Fluxo , Neoplasias Gastrointestinais/cirurgia , Glutamina/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Neutrófilos/metabolismo , Período Pós-Operatório , Distribuição Aleatória
20.
Nutrition ; 13(1): 8-12, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9058440

RESUMO

Previous human studies have investigated the influences of nutritional routes on the serum kinetics of cytokines following intravenous administration of lipopolysaccharide. However, it is unclear whether preoperative nutritional routes influence responses of systemic cytokines in patients after surgery. This study was designed to investigate whether preoperative total parental nutrition (TPN) influences systemic interleukin-6 (IL-6) and interleukin-8 (IL-8) responses in patients following surgery for colorectal cancer. Patients with colorectal cancer received TPN (TPN group, n = 6) or an oral diet (oral group n = 6) for more than 7 d before the operation. Patients in the TPN group received standard TPN. Patients in the oral group received an ordinary hospital diet. Blood samples were collected before the operation, on postoperative day 1 (POD1), POD3, and POD7. Levels of IL-6, IL-8, and C-reactive protein (CRP) in plasma were determined. The characteristics of patients in the TPN and oral groups were comparable. Mean carbohydrate intake was greater (28 versus 19 kCal/kg), and lipid intake was smaller (0 versus 7 kCal/kg) in the TPN group than in the oral group. Plasma CRP levels did not differ between the two groups. Plasma IL-6 and IL-8 levels were marginally higher before the operation and were significantly higher on POD1 in the TPN group than in the oral group. The IL-6 levels showed a positive regression relation with the amounts of blood loss only in the TPN group (P < 0.05, r = 0.881). The slope of the regression line was steeper in the TPN group than in the total enteral nutrition (TEN) group (P < 0.01). In conclusion, routes of nutritional supply have an impact on the production of systemic cytokines after insult. The postoperative systemic IL-6 and IL-8 responses in patients who received standard TPN preoperatively were greater than in patients who received an oral diet. Preoperative nutrition via the enteral route may provide better regulation of cytokine responses after surgery than parenteral nutrition.


Assuntos
Neoplasias Colorretais/cirurgia , Citocinas/sangue , Nutrição Parenteral Total , Cuidados Pré-Operatórios , Citocinas/metabolismo , Feminino , Humanos , Interleucina-6/sangue , Interleucina-6/metabolismo , Interleucina-8/sangue , Interleucina-8/metabolismo , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Prospectivos , Fatores de Tempo
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