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1.
Crit Care Med ; 50(5): e468-e476, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35044966

RESUMO

OBJECTIVES: Extracorporeal carbon dioxide removal is used to treat patients suffering from acute respiratory failure. However, the procedure is hampered by the high blood flow required to achieve a significant CO2 clearance. We aimed to develop an ultralow blood flow device to effectively remove CO2 combined with continuous renal replacement therapy (CRRT). DESIGN: Preclinical, proof-of-concept study. SETTING: An extracorporeal circuit where 200 mL/min of blood flowed through a hemofilter connected to a closed-loop dialysate circuit. An ion-exchange resin acidified the dialysate upstream, a membrane lung to increase Pco2 and promote CO2 removal. PATIENTS: Six, 38.7 ± 2.0-kg female pigs. INTERVENTIONS: Different levels of acidification were tested (from 0 to 5 mEq/min). Two l/hr of postdilution CRRT were performed continuously. The respiratory rate was modified at each step to maintain arterial Pco2 at 50 mm Hg. MEASUREMENTS AND MAIN RESULTS: Increasing acidification enhanced CO2 removal efficiency of the membrane lung from 30 ± 5 (0 mEq/min) up to 145 ± 8 mL/min (5 mEq/min), with a 483% increase, representing the 73% ± 7% of the total body CO2 production. Minute ventilation decreased accordingly from 6.5 ± 0.7 to 1.7 ± 0.5 L/min. No major side effects occurred, except for transient tachycardia episodes. As expected from the alveolar gas equation, the natural lung Pao2 dropped at increasing acidification steps, given the high dissociation between the oxygenation and CO2 removal capability of the device, thus Pao2 decreased. CONCLUSIONS: This new extracorporeal ion-exchange resin-based multiple-organ support device proved extremely high efficiency in CO2 removal and continuous renal support in a preclinical setting. Further studies are required before clinical implementation.


Assuntos
Terapia de Substituição Renal Contínua , Animais , Dióxido de Carbono , Soluções para Diálise , Feminino , Humanos , Oxigênio , Respiração Artificial/métodos , Suínos
2.
FASEB J ; 32(10): 5532-5549, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29718705

RESUMO

Despite increasing clinical adoption, biologic influences of ex vivo lung perfusion (EVLP) remain insufficiently elucidated. The aim of the current study was to investigate biomolecular changes induced by EVLP in rat lungs. EVLP was maintained for 180 min. Hyaluronan, mediators, and cells were assessed in the perfusate. Gene expression, signaling pathways, and ATP content were investigated in lung tissue. EVLP induced the release of medium-high molecular weight hyaluronan and transcription of hyaluronan synthases ( P < 0.001). Increasing concentrations of inflammatory mediators were detected in the perfusate ( P < 0.001). Perfused lungs exhibited a distinctive transcriptional signature compared with organs examined before or after surgery/procurement ( P = 0.003). Up-regulated genes were involved in inflammation and its regulation, apoptosis/survival, heat shock, and oxidative stress response ( q = 0). Down-regulated genes were related to lymphocyte function ( q = 0). The NF-κB, signal transducer and activator of transcription 3, ERK1/2, p38, Akt, and stress-activated protein kinase/JNK signaling pathways were modulated by EVLP ( P < 0.05). Most of these biomolecular changes were examined and confirmed in additional experiments that were performed in lungs procured from donation after cardiocirculatory death after 180 min of warm ischemia. The current study demonstrates that EVLP broadly affects the lung biomolecular phenotype. These findings improve our comprehension of the effects exerted by the procedure and encourage additional research in preclinical models to implement therapeutic interventions.-Lonati, C., Bassani, G. A., Brambilla, D., Leonardi, P., Carlin, A., Faversani, A., Gatti, S., Valenza, F. Influence of ex vivo perfusion on the biomolecular profile of rat lungs.


Assuntos
Apoptose , Resposta ao Choque Térmico , Pulmão/metabolismo , Sistema de Sinalização das MAP Quinases , Estresse Oxidativo , Perfusão , Animais , Sobrevivência Celular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Hialuronan Sintases/metabolismo , Ácido Hialurônico/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
3.
Perfusion ; 33(7): 577-583, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29783879

RESUMO

INTRODUCTION: Citric acid infusion in extracorporeal blood may allow concurrent regional anticoagulation and enhancement of extracorporeal CO2 removal. Effects of citric acid on human blood thromboelastography and aggregometry have never been tested before. METHODS: In this in vitro study, citric acid, sodium citrate and lactic acid were added to venous blood from seven healthy donors, obtaining concentrations of 9 mEq/L, 12 mEq/L and 15 mEq/L. We measured gas analyses, ionized calcium (iCa++) concentration, activated clotting time (ACT), thromboelastography and multiplate aggregometry. Repeated measure analysis of variance was used to compare the acidifying and anticoagulant properties of the three compounds. RESULTS: Sodium citrate did not affect the blood gas analysis. Increasing doses of citric and lactic acid progressively reduced pH and HCO3- and increased pCO2 (p<0.001). Sodium citrate and citric acid similarly reduced iCa++, from 0.39 (0.36-0.39) and 0.35 (0.33-0.36) mmol/L, respectively, at 9 mEq/L to 0.20 (0.20-0.21) and 0.21 (0.20-0.23) mmol/L at 15 mEq/L (p<0.001). Lactic acid did not affect iCa++ (p=0.07). Sodium citrate and citric acid similarly incremented the ACT, from 234 (208-296) and 202 (178-238) sec, respectively, at 9 mEq/L, to >600 sec at 15 mEq/L (p<0.001). Lactic acid did not affect the ACT values (p=0.486). Sodium citrate and citric acid similarly incremented R-time and reduced α-angle and maximum amplitude (MA) (p<0.001), leading to flat-line thromboelastograms at 15 mEq/L. Platelet aggregometry was not altered by any of the three compounds. CONCLUSIONS: Citric acid infusions determine acidification and anticoagulation of blood similar to lactic acid and sodium citrate, respectively.


Assuntos
Anticoagulantes/uso terapêutico , Coagulação Sanguínea/efeitos dos fármacos , Ácido Cítrico/uso terapêutico , Ácido Láctico/uso terapêutico , Citrato de Sódio/uso terapêutico , Anticoagulantes/farmacologia , Ácido Cítrico/farmacologia , Feminino , Voluntários Saudáveis , Humanos , Ácido Láctico/farmacologia , Masculino , Citrato de Sódio/farmacologia
4.
GE Port J Gastroenterol ; 30(Suppl 2): 21-25, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38020816

RESUMO

Introduction: Tuberculosis remains a public health concern in developing countries, as well as in developed countries as a result of immigration from endemic areas. Gastroduodenal and colorectal tuberculosis are rare manifestations of gastrointestinal infection. Case Presentation: We present 2 cases of gastric, duodenal, and colorectal tuberculosis. The first case, a 17-year-old male with no medical record, presented with chronic diarrhea and abdominal pain. At endoscopy, he had multiple ulcers in the stomach, colon, and rectum, which were positive to Mycobacterium tuberculosis. The second case was a 43-year-old HIV-positive male, with a history of intermittent fever, nausea, and vomiting. Upper gastrointestinal endoscopy revealed a deep ulcer on gastric fundus that tested positive to M. tuberculosis in the acid-fast bacilli staining. Discussion/Conclusion: Gastroduodenal and colorectal tuberculosis, although rare, should be considered in the differential diagnosis in both immunosuppressed and immunocompetent patients. An adequate tissue sample and appropriate diagnostic tests are essential for the diagnosis and prompt start of first-line antituberculosis agents.


Introdução: A tuberculose continua sendo um problema de saúde pública nos países em desenvolvimento, bem como nos países desenvolvidos, em decorrência da imigração. A tuberculose gastroduodenal e colorretalsão manifestações raras de infecção gastrointestinal. Apresentação do Caso: Apresentamos dois casos de tuberculose gástrica, duodenal ecolorretal. O primeiro caso, um jovem de 17 anos, apresentou diarreia crônica e dor abdominal. Na endoscopia, tinha múltiplas úlceras no estômago, cólon e reto que foram positivas para Mycobacterium Tuberculosis. O segundo caso foi um homem de 43 anos, HIV positivo, com relato de febre intermitente, náuseas e vômitos. A endoscopia digestiva alta revelou úlcera profunda do fundo gástrico positivo para Mycobacterium tuberculosis na coloração de bacilos álcool-ácido resistentes. Discussão/Conclusão: Tuberculosegastroduodenal e colorretal, embora raras, deve ser considerada como diagnóstico em pacientes imunossuprimidos e imunocompetentes. Uma amostra de tecido adequada e testes diagnósticos apropriados são essenciais para o diagnósticoe início imediato dos tuberculostáticos de primeira linha.

5.
Minerva Anestesiol ; 89(9): 773-782, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36951601

RESUMO

BACKGROUND: Extracorporeal carbon dioxide removal (ECCO2R) promotes protective ventilation in patients with acute respiratory failure, but devices with high CO2 extraction capacity are required for clinically relevant impact. This study evaluates three novel low-flow techniques based on dialysate acidification, also combined with renal replacement therapy, and metabolic control. METHODS: Eight swine were connected to a low-flow (350 mL/min) extracorporeal circuit including a dialyzer with a closed-loop dialysate circuit, and two membrane lungs on blood (MLb) and dialysate (MLd), respectively. The following 2-hour steps were performed: 1) MLb-start (MLb ventilated); 2) MLbd-start (MLb and MLd ventilated); 3) HLac (lactic acid infusion before MLd); 4) HCl-NaLac (hydrochloric acid infusion before MLd combined with renal replacement therapy and reinfusion of sodium lactate); 5) HCl-ßHB-NaLac (hydrochloric acid infusion before MLd combined with renal replacement therapy and reinfusion of sodium lactate and sodium 3-hydroxybutyrate). Caloric and fluid inputs, temperature, blood glucose and arterial carbon dioxide pressure were kept constant. RESULTS: The total MLs CO2 removal in HLac (130±25 mL/min), HCl-NaLac (130±21 mL/min) and HCl-ßHB-NaLac (124±18 mL/min) were higher compared with MLbd-start (81±15 mL/min, P<0.05) and MLb-start (55±7 mL/min, P<0.05). Minute ventilation in HLac (4.3±0.9 L/min), HCl-NaLac (3.6±0.8 L/min) and HCl-ßHB-NaLac (3.6±0.8 L/min) were lower compared to MLb-start (6.2±1.1 L/min, P<0.05) and MLbd-start (5.8±2.1 L/min, P<0.05). Arterial pH was 7.40±0.03 at MLb-start and decreased only during HCl-ßHB-NaLac (7.35±0.03, P<0.05). No relevant changes in electrolyte concentrations, hemodynamics and significant adverse events were detected. CONCLUSIONS: The three techniques achieved a significant extracorporeal CO2 removal allowing a relevant reduction in minute ventilation with a sufficient safety profile.


Assuntos
Dióxido de Carbono , Respiração Artificial , Animais , Suínos , Respiração Artificial/métodos , Lactato de Sódio , Ácido Clorídrico , Concentração de Íons de Hidrogênio , Soluções para Diálise
6.
Anesthesiology ; 116(3): 692-700, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22266570

RESUMO

BACKGROUND: Melanocortin peptides improve hemodynamic parameters and prevent death during severe hemorrhagic shock. In the present research we determined influences of a synthetic melanocortin 1/4 receptor agonist on the molecular changes that occur in rat liver during hemorrhage. METHODS: Controlled-volume hemorrhage was performed in adult rats under general anesthesia by a stepwise blood withdrawal until mean arterial pressure fell to 40 mmHg. Then rats received either saline or the synthetic melanocortin 1/4 receptor agonist Butir-His-D-Phe-Arg-Trp-Sar-NH2 (Ro27-3225; n = 6-8 per group). Hemogasanalysis was performed throughout a 60-min period. Gene expression in liver samples was determined at 1 or 3 h using quantitative real-time polymerase chain reaction. RESULTS: At 1 h, in saline-treated shocked rats, there were significant increases in activating transcription factor 3 (Atf3), early growth response 1 (Egr1), heme oxygenase (decycling) 1 (Hmox1), FBJ murine osteosarcoma viral oncogene homolog (Fos), and jun oncogene (Jun). These changes were prevented by Ro27-3225 (mean ± SEM: Atf3 152.83 ± 58.62 vs. 579.00 ± 124.13, P = 0.002; Egr1 13.21 ± 1.28 vs. 26.63 ± 1.02, P = 0.001; Hmox1 3.28 ± 0.31 vs. 166.54 ± 35.03, P = 0.002; Fos 4.36 ± 1.03 vs. 14.90 ± 3.44, P < 0.001; Jun 6.62 ± 1.93 vs. 15.07 ± 2.09, P = 0.005; respectively). Increases in alpha-2-macroglobulin (A2m), heat shock 70kD protein 1A (Hspa1a), erythropoietin (Epo), and interleukin-6 (Il6) occurred at 3 h in shocked rats and were prevented by Ro27-3225 treatment (A2m 6.90 ± 0.82 vs. 36.73 ± 4.00, P < 0.001; Hspa1a 10.34 ± 3.28 vs. 25.72 ± 3.64, P = 0.001; Epo 0.49 ± 0.13 vs. 2.37 ± 0.73, P = 0.002; Il6 1.05 ± 0.15 vs. 1.88 ± 0.23, P < 0.001; respectively). Further, at 3 h in shocked rats treated with Ro27-3225 there were significant increases in tight junction protein 1 (Tjp1; 27.30 ± 2.43 vs. 5.03 ± 1.68, P < 0.001) and nuclear receptor subfamily 4, group A, member 1 (Nr4a1; 91.03 ± 16.20 vs. 30.43 ± 11.0, P = 0.01) relative to sham animals. Treatment with Ro27-3225 rapidly restored blood pressure, hemogasanalysis parameters, and lactate blood levels. CONCLUSIONS: Melanocortin treatment significantly prevents most of the systemic and hepatic detrimental changes induced by hemorrhage.


Assuntos
Melanocortinas/uso terapêutico , Peptídeos/uso terapêutico , Choque Hemorrágico/tratamento farmacológico , Choque Hemorrágico/metabolismo , Animais , Melanocortinas/metabolismo , Peptídeos/metabolismo , Ratos , Ratos Wistar , Receptor Tipo 1 de Melanocortina/agonistas , Receptor Tipo 1 de Melanocortina/fisiologia , Receptor Tipo 4 de Melanocortina/agonistas , Receptor Tipo 4 de Melanocortina/fisiologia , Choque Hemorrágico/genética , Resultado do Tratamento
7.
J Clin Med ; 11(11)2022 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-35683455

RESUMO

The acceptable duration of donor warm ischemia time (DWIT) after cardiocirculatory death (DCD) is still debated. We analyzed the biomolecular profile and function during ex vivo lung perfusion (EVLP) of DCD lungs and their correlation with lung transplantation (LuTx) outcomes. Donor data, procurement times, recipient outcomes, and graft function up to 1 year after LuTx were collected. During EVLP, the parameters of graft function and metabolism, perfusate samples to quantify inflammation, glycocalyx breakdown products, coagulation, and endothelial activation markers were obtained. Data were compared to a cohort of extended-criteria donors after brain death (EC-DBD). Eight DBD and seven DCD grafts transplanted after EVLP were analyzed. DCD's DWIT was 201 [188;247] minutes. Donors differed only regarding the duration of mechanical ventilation that was longer in the EC-DBD group. No difference was observed in lung graft function during EVLP. At reperfusion, "wash-out" of inflammatory cells and microthrombi was predominant in DCD grafts. Perfusate biomolecular profile demonstrated marked endothelial activation, characterized by the presence of inflammatory mediators and glycocalyx breakdown products both in DCD and EC-DBD grafts. Early graft function after LuTx was similar between DCD and EC-DBD. DCD lungs exposed to prolonged DWIT represent a potential resource for donation if properly preserved and evaluated.

8.
Peptides ; 141: 170552, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33865932

RESUMO

The increasing use of marginal lungs for transplantation encourages novel approaches to improve graft quality. Melanocortins and their receptors (MCRs) exert multiple beneficial effects in pulmonary inflammation. We tested the idea that treatment with the synthetic α-melanocyte-stimulating hormone analogue [Nle4,D-Phe7]-α-MSH (NDP-MSH) during ex vivo lung perfusion (EVLP) could exert positive influences in lungs exposed to different injuries. Rats were assigned to one of the following protocols (N = 10 each): 1) ischemia/reperfusion (IR) or 2) cardiac death (CD) followed by ex vivo perfusion. NDP-MSH treatment was performed in five rats of each protocol before lung procurement and during EVLP. Pulmonary function and perfusate concentration of gases, electrolytes, metabolites, nitric-oxide, mediators, and cells were assessed throughout EVLP. ATP content and specific MCR expression were investigated in perfused lungs and in biopsies collected from rats in resting conditions (Native, N = 5). NDP-MSH reduced the release of inflammatory mediators in perfusates of both the IR and the CD groups. Treatment was likewise associated with a lesser amount of leukocytes (IR: p = 0.034; CD: p = 0.002) and reduced lactate production (IR: p = 0.010; CD: p = 0.008). In lungs exposed to IR injury, the NDP-MSH group showed increased ATP content (p = 0.040) compared to controls. In CD lungs, a significant improvement of vascular (p = 0.002) and airway (Ppeak: p < 0.001, compliance: p < 0.050, pO2: p < 0.001) parameters was observed. Finally, the expression of MC1R and MC5R was detected in both native and ex vivo-perfused lungs. The results indicate that NDP-MSH administration preserves lung function through broad positive effects on multiple pathways and suggest that exploitation of the melanocortin system during EVLP could improve reconditioning of marginal lungs before transplantation.


Assuntos
Pulmão/efeitos dos fármacos , Pulmão/fisiologia , Perfusão/métodos , alfa-MSH/análogos & derivados , Trifosfato de Adenosina/metabolismo , Animais , Morte , Ácido Hialurônico/metabolismo , Mediadores da Inflamação/metabolismo , Ácido Láctico/metabolismo , Pulmão/fisiopatologia , Masculino , Técnicas de Cultura de Órgãos , Perfusão/efeitos adversos , Edema Pulmonar/etiologia , Ratos Sprague-Dawley , Receptores de Melanocortina/genética , Receptores de Melanocortina/metabolismo , Traumatismo por Reperfusão/prevenção & controle , alfa-MSH/farmacologia
9.
ScientificWorldJournal ; 10: 1840-53, 2010 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-20852827

RESUMO

Melanocortin peptides, the collective term for alpha-, beta-, and gamma-melanocyte-stimulating hormone (alpha-, beta-, gamma-MSH) and adrenocorticotropic hormone (ACTH), are elements of an ancient modulatory system. Natural melanocortins derive from the common precursor pro-opiomelanocortin (POMC). Five receptor subtypes for melanocortins (MC1-MC5) are widely distributed in brain regions and in peripheral cells. Melanocortin receptor activation by natural or synthetic ligands exerts marked anti-inflammatory and immunomodulatory effects. The anticytokine action and the inhibitory influences on inflammatory cell migration make melanocortins potential new drugs for treatment of inflammatory disorders. Effectiveness in treatment of acute, chronic, and systemic inflammatory disorders is well documented in preclinical studies. Further, melanocortins are promising compounds in neuroprotection. This review examines the main signaling circuits in anti-inflammatory and immunomodulatory actions of melanocortins, and the potential therapeutic use of these molecules.


Assuntos
Encéfalo/efeitos dos fármacos , Inflamação/prevenção & controle , Melanocortinas/farmacologia , Receptores de Melanocortina/metabolismo , Hormônio Adrenocorticotrópico/metabolismo , Hormônio Adrenocorticotrópico/farmacologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Humanos , Inflamação/metabolismo , Melanocortinas/metabolismo , Modelos Biológicos , Pró-Opiomelanocortina/metabolismo , Transdução de Sinais/efeitos dos fármacos
10.
J Heart Lung Transplant ; 38(12): 1306-1316, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31530458

RESUMO

BACKGROUND: Lung ischemia/reperfusion (IR) injury contributes to the development of severe complications in patients undergoing transplantation. Mesenchymal stem cell (MSC)-derived extracellular vesicles (EVs) exert beneficial actions comparable to those of MSCs without the risks of the cell-based strategy. This research investigated EV effects during IR injury in isolated rat lungs. METHODS: An established model of 180-minutes ex vivo lung perfusion (EVLP) was used. At 60 minutes EVs (n = 5) or saline (n = 5) were administered. Parallel experiments used labeled EVs to determine EV biodistribution (n = 4). Perfusate samples were collected to perform gas analysis and to assess the concentration of nitric oxide (NO), hyaluronan (HA), inflammatory mediators, and leukocytes. Lung biopsies were taken at 180 minutes to evaluate HA, adenosine triphosphate (ATP), gene expression, and histology. RESULTS: Compared with untreated lungs, EV-treated organs showed decreased vascular resistance and a rise of perfusate NO metabolites. EVs prevented the reduction in pulmonary ATP caused by IR. Increased medium-high-molecular-weight HA was detected in the perfusate and in the lung tissue of the IR + EV group. Significant differences in cell count on perfusate and tissue samples, together with induction of transcription and synthesis of chemokines, suggested EV-dependent modulation of leukocyte recruitment. EVs upregulated genes involved in the resolution of inflammation and oxidative stress. Biodistribution analysis showed that EVs were retained in the lung tissue and internalized within pulmonary cells. CONCLUSIONS: This study shows multiple novel EV influences on pulmonary energetics, tissue integrity, and gene expression during IR. The use of cell-free therapies during EVLP could constitute a valuable strategy for reconditioning and repair of injured lungs before transplantation.


Assuntos
Vesículas Extracelulares/transplante , Pulmão/irrigação sanguínea , Células-Tronco Mesenquimais/ultraestrutura , Traumatismo por Reperfusão/prevenção & controle , Animais , Fenótipo , Ratos , Traumatismo por Reperfusão/genética
11.
Brain Behav Immun ; 22(6): 817-23, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18178058

RESUMO

Prevention of graft dysfunction is a major objective in transplantation medicine. Previous research on experimental heart transplantation indicated that treatment with the immunomodulatory peptide alpha-melanocyte stimulating hormone (alpha-MSH) improves histopathology, prolongs allograft survival, and reduces expression of the main tissue injury mediators. Because calcium-handling is critical in heart graft function, we determined the effects of transplantation injury and influences of alpha-MSH treatment on representative calcium regulatory proteins in rat heart allografts. Hearts from Brown Norway rats were transplanted heterotopically into MHC incompatible Lewis rats. Ca(2+)/calmodulin-dependent protein kinase II (CaMKII), protein kinase C epsilon (PKC epsilon), sarcoplasmic/endoplasmic reticulum calcium-ATPase 2 (SERCA2a), arrestin-beta1 (Arrb1), cholinergic receptor M2 (Chrm2), and inositol 1,4,5-triphosphate receptor 1 (InsP(3)R1) were examined in: (1) non-transplanted donor hearts; (2) allografts from saline-treated rats; and (3) allografts from rats treated with the synthetic alpha-MSH analog Nle4-DPhe7-alpha-MSH (NDP-alpha-MSH) (100 microg i.p. every 12h). Transplantation injury was associated with severe reduction in calcium regulatory protein transcription and expression level. NDP-alpha-MSH administration partly reversed inhibition of protein transcription and almost completely prevented protein loss. Finally, because certain effects of cyclic 3'-5'-adenosine monophosphate (cAMP) signaling on calcium handling in cardiac myocytes depend on activation of exchange protein directly activated by cAMP 1 (Epac1), we determined Epac1 mRNA and protein expression in heart allografts. Transplantation injury markedly reduced Epac1. NDP-alpha-MSH treatment significantly preserved both Epac1 protein and mRNA in the allografts. Administration of alpha-MSH or related melanocortins could reduce transplantation-induced dysfunction through protection of heart calcium regulatory proteins.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Cálcio/metabolismo , Transplante de Coração/métodos , alfa-MSH/farmacologia , Animais , Arrestinas/genética , Arrestinas/metabolismo , Western Blotting , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , AMP Cíclico/genética , AMP Cíclico/metabolismo , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Rejeição de Enxerto/tratamento farmacológico , Sobrevivência de Enxerto/efeitos dos fármacos , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Receptores de Inositol 1,4,5-Trifosfato , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , Proteína Quinase C-épsilon/efeitos dos fármacos , Proteína Quinase C-épsilon/genética , Proteína Quinase C-épsilon/metabolismo , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Receptores Colinérgicos/genética , Receptores Colinérgicos/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/efeitos dos fármacos , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , beta-Arrestina 1 , beta-Arrestinas
12.
Shock ; 27(3): 326-33, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17304115

RESUMO

Alpha-melanocyte-stimulating hormone (alpha-MSH) is a peptide with broad anti-inflammatory effects. The present research was designed to determine production and effects of alpha-MSH in acute bleomycin-induced lung injury in rats. Intratracheal bleomycin instillation induced alpha-MSH expression in lung infiltrating cells and a marked peptide increase in the circulation. In experiments on the therapeutic potential of alpha-MSH on lung injury, we determined influences of the synthetic alpha-MSH analogue [Nle4-dPhe7]-alpha-MSH (NDP-alpha-MSH) on pulmonary edema, circulating nitric oxide, and gene expression profile in lungs 8 and 24 h after bleomycin instillation. Three main gene categories, known to be involved in the development of acute lung injury, were explored: stress response, inflammation, and fluid homeostasis. Peptide treatment was associated with a significant reduction in interstitial edema, with a virtually normal wet/dry weight ratio. Several stress-related genes, which were either upregulated or reduced by bleomycin, were only marginally altered during NDP-alpha-MSH treatment. NDP-alpha-MSH prevented bleomycin-related transcriptional alterations in genes involved in lung fluid homeostasis, including upregulation of Na/K-transporting ATPase and epithelial sodium channels and downregulation of cystic fibrosis transmembrane conductance regulator. Bleomycin-induced expression of proinflammatory and profibrotic factors (interleukin 6, tumor necrosis factor-alpha, transforming growth factor-beta1, and inducible nitric oxide synthase) and chemokines (chemokine [C-C motif] ligand 2 and chemokine [C-C motif] ligand 5) was likewise significantly reduced by NDP-alpha-MSH. In conclusion, treatment with the alpha-MSH analogue NDP-alpha-MSH greatly improved the clinical and molecular picture of bleomycin-induced lung injury. Treatment with alpha-MSH-related agents can exert beneficial effects in acute lung injury.


Assuntos
Lesão Pulmonar , alfa-MSH/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Bleomicina/farmacologia , Perfilação da Expressão Gênica , Imuno-Histoquímica , Inflamação , Pulmão/metabolismo , Pulmão/patologia , Masculino , Modelos Biológicos , Óxido Nítrico/química , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Ratos Wistar
13.
J Med Chem ; 48(5): 1384-8, 2005 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-15743181

RESUMO

Alpha-melanocyte stimulating hormone (alpha-MSH) is an endogenous antiinflammatory peptide with antimicrobial properties. We recently found that a synthetic analogue, [dNal(2')-7, Phe-12]-alpha-MSH (6-13), was considerably more potent in killing Candida albicans, but the anti-cytokine potential of the molecule was not investigated. Because molecules that combine candidacidal and antiinflammatory properties could be very useful in clinical practice, we measured the anti-TNF-alpha potential of [dNal(2')-7, Phe-12]-alpha-MSH (6-13) and explored effects of amino acid deletions and substitutions on both anti-Candida and anti-TNF-alpha activities. The results show that anti-TNF-alpha properties of this candidacidal peptide are only marginally increased relative to the native sequence. Conversely, we found that a closely related candidacidal analogue, [dNal(2')-7, Pro-12]-alpha-MSH (6-13), had enhanced anti-TNF-alpha effects in vitro and in vivo. This peptide, and other melanocortins with a similar dual effect, could be very useful to eradicate infections and, concurrently, reduce inflammatory reactions.


Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Antifúngicos/síntese química , Candida albicans/efeitos dos fármacos , Hormônios Estimuladores de Melanócitos/síntese química , Fragmentos de Peptídeos/síntese química , Fator de Necrose Tumoral alfa/antagonistas & inibidores , alfa-MSH/química , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Candida albicans/isolamento & purificação , Hormônios Estimuladores de Melanócitos/química , Hormônios Estimuladores de Melanócitos/farmacologia , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/biossíntese
14.
J Leukoc Biol ; 75(2): 253-9, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14576363

RESUMO

Malignant pleural mesothelioma is a highly aggressive tumor arising from the mesothelial cells that line the pleural cavities. This tumor is resistant to most conventional anticancer treatments and appears to be very sensitive to growth-promoting influences of cytokines and growth factors. Identification of natural inhibitory pathways that control growth should aid discovery of novel therapeutic approaches. We hypothesized that alpha-melanocyte-stimulating hormone (alpha-MSH), which is produced by many cell types and antagonizes cytokines and growth factors, could be an endogenous inhibitory molecule in mesothelioma. Twelve mesothelioma cell lines were established from pleural effusions of patients with malignant mesothelioma. Mesothelioma cells were found to express mRNA for proopiomelanocortin and its processing enzymes; release alpha-MSH peptide into supernatants; and express melanocortin 1 receptor (MC1R), the high-affinity receptor for alpha-MSH. Immunoneutralization of MC1R in the cell lines enhanced expression of interleukin-8 (IL-8), IL-6, and transforming growth factor-beta. These molecules promote mesothelioma proliferation and are considered therapeutic targets in this tumor. Coincubation of mesothelioma cells with synthetic alpha-MSH significantly reduced cell proliferation. The present research shows an autocrine-inhibitory circuit based on alpha-MSH and its receptor MC1R. Activation of MC1R by selective peptides or peptidomimetics might provide a novel strategy to reduce mesothelioma cell proliferation by taking advantage of this endogenous inhibitory circuit.


Assuntos
Comunicação Autócrina/fisiologia , Mesotelioma/patologia , Neoplasias Pleurais/patologia , alfa-MSH/fisiologia , Divisão Celular , Citocinas/biossíntese , Relação Dose-Resposta a Droga , Humanos , Imuno-Histoquímica , Mesotelioma/metabolismo , Fragmentos de Peptídeos/farmacologia , Neoplasias Pleurais/metabolismo , Pró-Opiomelanocortina/genética , RNA Neoplásico/análise , Receptor Tipo 1 de Melanocortina/análise , Células Tumorais Cultivadas , alfa-MSH/química
15.
Rev. colomb. gastroenterol ; 35(4): 533-536, dic. 2020. graf
Artigo em Espanhol | LILACS | ID: biblio-1156336

RESUMO

Resumen La esofagitis necrotizante aguda es una entidad poco común que afecta sobre todo a ancianos. La presentación clínica más común es hemorragia digestiva alta. El pronóstico depende de las enfermedades de base con una mortalidad de hasta el 50 %. Se presenta el caso de un varón de 77 años con historia de una semana de melena, 3 episodios de hematemesis y epigastralgia. La endoscopia digestiva alta reveló una mucosa con necrosis en parches y fibrina en el esófago medio y distal. La biopsia de esófago fue compatible con necrosis de mucosa.


Abstract Acute necrotizing esophagitis is a rare entity that affects mainly elderly patients. The most common clinical presentation is upper gastrointestinal bleeding. The prognosis depends on the underlying diseases, with a mortality of up to 50%. This is the case of a 77-year-old male patient who presented with melena, three episodes of hematemesis, and epigastric pain for a week. Upper endoscopy revealed mucosa with spotty necrosis and fibrin in the middle and distal esophagus. Esophageal biopsy was compatible with mucosal necrosis.


Assuntos
Humanos , Masculino , Idoso , Esôfago , Hemorragia , Hematemese , Melena , Mucosa , Necrose
16.
J Neurotrauma ; 20(3): 251-60, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12820679

RESUMO

The neuropeptide alpha-melanocyte-stimulating hormone (alpha-MSH) is a proopiomelanocortin derivative that has potent anti-inflammatory influences within the brain. The aim of the present research was to determine if there are changes in blood concentrations of this peptide in patients with acute traumatic brain injury (TBI) or subarachnoid hemorrhage (SAH). Concomitantly, we recorded clinical parameters and measured blood concentrations of the proinflammatory cytokine tumor necrosis factor-alpha (TNF-alpha). Twenty-three patients were enrolled in this study--18 had TBI and five SAH. Blood samples for determination of alpha-MSH and TNF-alpha were collected daily from day 1 to day 4 after injury. Baseline concentration of plasma alpha-MSH in patients with acute brain injury of either traumatic or vascular origin was significantly lower than in controls. Patients with TBI or SAH had similar alpha-MSH concentrations and the peptide remained consistently low over four post-injury days. Circulating TNF-alpha on day one was measurable in all patients and there was a negative correlation between plasma TNF-alpha and alpha-MSH. Alpha-MSH was measured again after the acute phase in eight patients. The peptide was substantially increased in all subjects except for two who had an unfavorable outcome. From the well-known protective anti-inflammatory influences of alpha-MSH in the host, reduction in this circulating peptide may have detrimental consequences in brain injury. The data raise the possibility that restoration of normal circulating alpha-MSH through administration of the peptide could be beneficial in patients with brain injury.


Assuntos
Lesões Encefálicas/sangue , alfa-MSH/sangue , Adolescente , Adulto , Fatores Etários , Idoso , Lesões Encefálicas/fisiopatologia , Feminino , Escala de Coma de Glasgow , Escala de Resultado de Glasgow , Humanos , Imunoensaio , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Hemorragia Subaracnóidea/sangue , Fatores de Tempo , Fator de Necrose Tumoral alfa/análise
17.
Intensive Care Med Exp ; 2(1): 12, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26266913

RESUMO

BACKGROUND: We set a model of brain death, donor management, and lung transplantation for studies on lung preservation and reconditioning before transplantation. METHODS: Ten pigs (39.7 ± 5.9 Kg) were investigated. Five animals underwent brain death and were treated as organ donors; the lungs were then procured and cold stored (Ischemia). Five recipients underwent left lung transplantation and post-reperfusion follow-up (Graft). Cardiorespiratory and metabolic parameters were collected. Lung gene expression of cytokines (tumor necrosis factor alpha (TNFα), interleukin-1 beta (IL-1ß), interleukin-6 (IL-6), interferon gamma (IFNγ), high mobility group box-1 (HMGB-1)), chemokines (chemokine CC motif ligand-2 (CCL2-MCP-1), chemokine CXC motif ligand-10 (CXCL-10), interleukin-8 (IL-8)), and endothelial activation markers (endothelin-1 (EDN-1), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), selectin-E (SELE)) was assessed by real-time polymerase chain reaction (PCR). RESULTS: Tachycardia and hypertension occurred during brain death induction; cardiac output rose, systemic vascular resistance dropped (P < 0.05), and diabetes insipidus occurred. Lung-protective ventilation strategy was applied: 9 h after brain death induction, PaO2 was 192 ± 12 mmHg at positive end-expiratory pressure (PEEP) 8.0 ± 1.8 cmH2O and FiO2 of 40%; wet-to-dry ratio (W/D) was 5.8 ± 0.5, and extravascular lung water (EVLW) was 359 ± 80 mL. Procured lungs were cold-stored for 471 ± 24 min (Ischemia) at the end of which W/D was 6.1 ± 0.9. Left lungs were transplanted and reperfused (warm ischemia 98 ± 14 min). Six hours after controlled reperfusion, PaO2 was 192 ± 23 mmHg (PEEP 8.7 ± 1.5 cmH2O, FiO2 40%), W/D was 5.6 ± 0.4, and EVLW was 366 ± 117 mL. Levels of IL-8 rose at the end of donor management (BD, P < 0.05); CCL2-MCP-1, IL-8, HMGB-1, and SELE were significantly altered after reperfusion (Graft, P < 0.05). CONCLUSIONS: We have set a standardized, reproducible pig model resembling the entire process of organ donation that may be used as a platform to test in vivo and ex vivo strategies of donor lung optimization before transplantation.

18.
Peptides ; 50: 145-52, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24446557

RESUMO

Melanocortins are endogenous peptides that exert protective actions on the host physiology. The broad modulatory effects of these molecules suggest that they might influence the mediator network induced during liver regeneration. The research aim was to determine if melanocortin treatment alters liver molecular changes induced by partial hepatectomy (PH). Rats under isoflurane anesthesia were subjected to standard 70% PH or sham surgery. Animals received a single i.v. injection of Nle4, DPhe7-α-melanocyte stimulating hormone (NDP-MSH) or saline 30 min before surgery. Sacrifice was performed at time intervals between 4 and 72 h. A preliminary screening based on TaqMan low-density array (TLDA) identified 71 transcripts altered by PH. Real-time PCR analysis revealed that NDP-MSH modulated the expression of a substantial proportion of these transcripts including several chemokines and their receptors. The critical signaling pathway interleukin-6 (IL-6)/signal transducer and activator of transcription (STAT)/suppressor of cytokine signaling (SOCS) was significantly enhanced by NDP-MSH. Further, peptide treatment considerably reduced the decline of IκBα protein caused by PH. Although the final organ regeneration was not substantially affected, NDP-MSH modulated expression of cell cycle mediators and exerted subtle influences on hepatocyte replication. Most of the changes brought about by NDP-MSH, a peptide approved for clinical use, should be salutary during liver regeneration.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Hepatectomia , Regeneração Hepática/efeitos dos fármacos , Fígado/efeitos dos fármacos , RNA Mensageiro/genética , alfa-MSH/análogos & derivados , Animais , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Quimiocinas/genética , Quimiocinas/metabolismo , Perfilação da Expressão Gênica , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Injeções Intravenosas , Fígado/citologia , Fígado/cirurgia , Regeneração Hepática/genética , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Quimiocinas/genética , Receptores de Quimiocinas/metabolismo , Transdução de Sinais , alfa-MSH/farmacologia
19.
Arch Argent Pediatr ; 110(5): e103-6, 2012 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-23070190

RESUMO

Mucopolysaccharidosis I (MPS I) is a rare, recessively inherited, lysosomal storage disorder caused by deficiency on the enzyme a-L-iduronidase. This defect results in accumulation of heparan and dermatan sulfate in different tissues and organs due to a deficiency in the catabolism of glycosaminoglycans. The overall incidence of MPS I is 0.99-1.99/100.000 live births. There are three clinical presentations: Hurler (severe), Hurler Scheie (mild) and Scheie (mild). We report the case of a 10-years-old male patient diagnosed with Hurler syndrome, the severe presentation, 5 years ago by enzyme a-L-iduronidase activity measurement in leukocytes; with a history of recurrent respiratory infections, umbilical hernia, corneal opacity, coarse facial features, macroglossia, hearing loss, stiffness of joints, cardiac compromise, claw hands, mental retardation and stunted growth. After enzyme replacement therapy the patient has shown improvement of visceral symptoms, but the neurological damage continuous in progress.


Assuntos
Mucopolissacaridose I , Criança , Terapia de Reposição de Enzimas , Humanos , Masculino , Mucopolissacaridose I/diagnóstico , Mucopolissacaridose I/tratamento farmacológico , Fenótipo
20.
Exp Neurol ; 234(1): 230-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22230666

RESUMO

Subarachnoid hemorrhage (SAH) is still a major cause of morbidity and mortality. α-Melanocyte stimulating hormone (α-MSH) and other melanocortin peptides exert potent neuroprotective action and they might modulate key molecules involved in SAH-induced vasospasm. The aim of this research was to determine whether treatment with the α-MSH analog Nle4,DPhe7-α-MSH (NDP-MSH) exerts protective effects in experimental SAH in the rat. Initial experiments examined effects of NDP-MSH on the basilar artery phenotype in the absence of injury. In these tests intrathecal injection of small concentrations (10ng) of the peptide induced a tolerant phenotype similar to that observed after ischemic preconditioning. Then the effect of systemic treatment with NDP-MSH (100µg i.v.) on experimental SAH was evaluated. SAH was induced by a single-blood injection into the cisterna magna. The basilar artery phenotype was examined at 4h and the artery caliber at 5days following SAH. Expression of 96 genes was analyzed by real-time reverse transcription polymerase chain reaction (RT-PCR) using Custom Taqman Low-Density Arrays. Four hours after SAH, the transcriptional profile of the basilar artery was deeply disrupted. Transcript alteration included genes involved in inflammation, stress response, apoptosis, and vascular remodeling. Treatment with NDP-MSH prevented most of these transcription changes and decreased phosphorylation of extracellular-signal-regulated kinases (ERK1/2) and inhibitor protein IκBα. Vasospasm on day 5 was significantly reduced by NDP-MSH administration. These results combine with others on CNS inflammation to suggest that the melanocortins could be safe and effective therapeutic candidates to treat SAH-related complications.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Hemorragia Subaracnóidea/tratamento farmacológico , Vasoespasmo Intracraniano/prevenção & controle , alfa-MSH/análogos & derivados , Análise de Variância , Animais , Artéria Basilar/efeitos dos fármacos , Artéria Basilar/patologia , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Hemorragia Subaracnóidea/complicações , Vasoespasmo Intracraniano/etiologia , alfa-MSH/uso terapêutico
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