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1.
J Neuroinflammation ; 20(1): 255, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37941007

RESUMO

BACKGROUND: Enteric glia contribute to the pathophysiology of various intestinal immune-driven diseases, such as postoperative ileus (POI), a motility disorder and common complication after abdominal surgery. Enteric gliosis of the intestinal muscularis externa (ME) has been identified as part of POI development. However, the glia-restricted responses and activation mechanisms are poorly understood. The sympathetic nervous system becomes rapidly activated by abdominal surgery. It modulates intestinal immunity, innervates all intestinal layers, and directly interfaces with enteric glia. We hypothesized that sympathetic innervation controls enteric glia reactivity in response to surgical trauma. METHODS: Sox10iCreERT2/Rpl22HA/+ mice were subjected to a mouse model of laparotomy or intestinal manipulation to induce POI. Histological, protein, and transcriptomic analyses were performed to analyze glia-specific responses. Interactions between the sympathetic nervous system and enteric glia were studied in mice chemically depleted of TH+ sympathetic neurons and glial-restricted Sox10iCreERT2/JellyOPfl/+/Rpl22HA/+ mice, allowing optogenetic stimulation of ß-adrenergic downstream signaling and glial-specific transcriptome analyses. A laparotomy model was used to study the effect of sympathetic signaling on enteric glia in the absence of intestinal manipulation. Mechanistic studies included adrenergic receptor expression profiling in vivo and in vitro and adrenergic agonism treatments of primary enteric glial cell cultures to elucidate the role of sympathetic signaling in acute enteric gliosis and POI. RESULTS: With ~ 4000 differentially expressed genes, the most substantial enteric glia response occurs early after intestinal manipulation. During POI, enteric glia switch into a reactive state and continuously shape their microenvironment by releasing inflammatory and migratory factors. Sympathetic denervation reduced the inflammatory response of enteric glia in the early postoperative phase. Optogenetic and pharmacological stimulation of ß-adrenergic downstream signaling triggered enteric glial reactivity. Finally, distinct adrenergic agonists revealed ß-1/2 adrenoceptors as the molecular targets of sympathetic-driven enteric glial reactivity. CONCLUSIONS: Enteric glia act as early responders during post-traumatic intestinal injury and inflammation. Intact sympathetic innervation and active ß-adrenergic receptor signaling in enteric glia is a trigger of the immediate glial postoperative inflammatory response. With immune-activating cues originating from the sympathetic nervous system as early as the initial surgical incision, adrenergic signaling in enteric glia presents a promising target for preventing POI development.


Assuntos
Sistema Nervoso Entérico , Gliose , Animais , Camundongos , Adrenérgicos , Neuroglia , Transdução de Sinais , Sistema Nervoso Simpático
2.
Liver Transpl ; 29(9): 928-939, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36950832

RESUMO

Acute-on-chronic liver failure (ACLF) is associated with organ failure and high short-term mortality. Bacterial infections and surgery have been reported as major precipitants for ACLF. However, detailed characterization of postoperative infections after elective surgery in patients with liver cirrhosis and their impact on the development of ACLF have not been investigated yet. A total of 235 patients with cirrhosis without ACLF and proven bacterial infections undergoing elective surgery were included. The primary end point was the development of ACLF within 28 days after surgery, and secondary end points were infection development within 28 days and 3-month ACLF-related mortality. Cox regression analysis was used for identification of risk factors associated with ACLF development, infection development, and mortality. A total of 86 patients (37%) developed ACLF within 28 days after surgery. Patients with new postoperative infections had significantly higher rates of associated ACLF episodes within 28 days (51% vs. 24%, p < 0.001) and higher 3-month mortality ( p < 0.05) than patients without postoperative infections. New infections after surgery [HR: 2.43 (1.59-3.71), p < 0.001] and organ/space surgical site infections [HR: 2.46 (1.26-4.80), p = 0.01] in particular were independent risk factors associated with ACLF development 28 days after surgery. Extensive procedures were associated with the development of new postoperative infection episodes within 28 days. Infections treated with initial appropriate empirical antibiotic strategies showed significantly improved survival. This study characterizes and identifies bacterial infections in general and organ/space surgical site infection in particular as precipitating events for the development of ACLF after elective surgery in patients with cirrhosis. Postoperative ACLF combined with infections leads to higher postoperative short-term mortality than each condition separately, especially in extensive procedures. Interdisciplinary care, early identification of postoperative ACLF and infections, and adequate, broad, and early treatment strategies are needed to improve postoperative outcome.


Assuntos
Insuficiência Hepática Crônica Agudizada , Infecções Bacterianas , Transplante de Fígado , Humanos , Insuficiência Hepática Crônica Agudizada/diagnóstico , Insuficiência Hepática Crônica Agudizada/epidemiologia , Insuficiência Hepática Crônica Agudizada/etiologia , Infecção da Ferida Cirúrgica/complicações , Infecção da Ferida Cirúrgica/diagnóstico , Infecção da Ferida Cirúrgica/epidemiologia , Prognóstico , Transplante de Fígado/efeitos adversos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Cirrose Hepática/cirurgia , Infecções Bacterianas/complicações , Infecções Bacterianas/epidemiologia
3.
Int J Colorectal Dis ; 37(1): 259-270, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34599686

RESUMO

PURPOSE: Surgery initiates pro-inflammatory mediator cascades leading to a variably pronounced sterile inflammation (SIRS). SIRS is associated with intestinal paralysis and breakdown of intestinal barrier and might result in abdominal sepsis. Technological progress led to the development of a neurostimulator for transcutaneous auricular vagal nerve stimulation (taVNS), which is associated with a decline in inflammatory parameters and peristalsis improvement in rodents and healthy subjects via activation of the cholinergic anti-inflammatory pathway. Therefore, taVNS might be a strategy for SIRS prophylaxis. METHODS: The NeuroSIRS-Study is a prospective, randomized two-armed, sham-controlled, double-blind clinical trial. The study is registered at DRKS00016892 (09.07.2020). A controlled endotoxemia is used as a SIRS-mimicking model. 2 ng/kg bodyweight lipopolysaccharide (LPS) will be administered after taVNS or sham stimulation. The primary objective is a reduction of clinical symptoms of SIRS after taVNS compared to sham stimulation. Effects of taVNS on release of inflammatory cytokines, intestinal function, and vital parameters will be analyzed. DISCUSSION: TaVNS is well-tolerated, with little to no side effects. Despite not fully mimicking postoperative inflammation, LPS challenge is the most used experimental tool to imitate SIRS and offers standardization and reproducibility. The restriction to healthy male volunteers exerts a certain bias limiting generalizability to the surgical population. Still, this pilot study aims to give first insights into taVNS as a prophylactic treatment in postoperative inflammation to pave the way for further clinical trials in patients at risk for SIRS. This would have major implications for future therapeutic approaches.


Assuntos
Insuficiência Intestinal , Estimulação Elétrica Nervosa Transcutânea , Estimulação do Nervo Vago , Voluntários Saudáveis , Humanos , Masculino , Projetos Piloto , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Reprodutibilidade dos Testes , Síndrome de Resposta Inflamatória Sistêmica/prevenção & controle
4.
Eur Surg Res ; 63(4): 224-231, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35184063

RESUMO

INTRODUCTION: Previous work of our group showed that lipoxygenase (LOX) pathways become activated upon surgical manipulation of the bowel wall and revealed a beneficial immune modulating role of the LOX-derived anti-inflammatory mediator protectin DX in postoperative ileus (POI). While we found a particular role of 12/15-LOX in the anti-inflammatory LOX action during POI, the role of 5-LOX, which produces the pro-inflammatory leukotriene B4 (LTB4), remained unknown. The purpose of this study was to investigate the role of 5-LOX within the pathogenesis of POI in a mouse model. METHODS: POI was induced by intestinal manipulation (IM) of the small bowel in C57BL/6, 5-LOX-/-, and CX3CR1GFP/+. Mice were either treated with a vehicle or with the synthetic 5-LOX antagonist zileuton or were left untreated. Cellular localization of 5-LOX and LTB4 release were visualized by immunofluorescence or ELISA, respectively. POI severity was quantified by gastrointestinal transit (GIT) and leukocyte extravasation into the muscularis externa (ME) by immunohistochemistry. RESULTS: 5-LOX expression was detected 24 h after IM within infiltrating leukocytes in the ME. LTB4 levels increased during POI in wild type but not in 5-LOX-/- after IM. POI was ameliorated in 5-LOX-/- as shown by decreased leukocyte numbers and normalized GIT. Zileuton normalized the postoperative GIT and reduced the numbers of infiltrating leukocytes into the ME. DISCUSSION/CONCLUSION: Our data demonstrate that 5-LOX and its metabolite LTB4 play a crucial role in POI. Genetic deficiency of 5-LOX and pharmacological antagonism by zileuton protected mice from POI. 5-LOX antagonism might be a promising target for prevention of POI in surgical patients.


Assuntos
Araquidonato 5-Lipoxigenase , Íleus , Camundongos , Animais , Leucotrieno B4 , Camundongos Endogâmicos C57BL , Íleus/tratamento farmacológico , Íleus/etiologia , Íleus/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle
5.
Int J Colorectal Dis ; 36(9): 2017-2025, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33977334

RESUMO

PURPOSE: Postoperative Ileus (POI) remains an important complication for patients after abdominal surgery with an incidence of 10-27% representing an everyday issue for abdominal surgeons. It accounts for patients' discomfort, increased morbidity, prolonged hospital stays, and a high economic burden. This review outlines the current understanding of POI pathophysiology and focuses on preventive treatments that have proven to be effective or at least show promising effects. METHODS: Pathophysiology and recommendations for POI treatment are summarized on the basis of a selective literature review. RESULTS: While a lot of therapies have been researched over the past decades, many of them failed to prove successful in meta-analyses. To date, there is no evidence-based treatment once POI has manifested. In the era of enhanced recovery after surgery or fast track regimes, a few approaches show a beneficial effect in preventing POI: multimodal, opioid-sparing analgesia with placement of epidural catheters or transverse abdominis plane block; µ-opioid-receptor antagonists; and goal-directed fluid therapy and in general the use of minimally invasive surgery. CONCLUSION: The results of different studies are often contradictory, as a concise definition of POI and reliable surrogate endpoints are still absent. These will be needed to advance POI research and provide clinicians with consistent data to improve the treatment strategies.


Assuntos
Neoplasias Colorretais , Íleus , Analgésicos Opioides , Humanos , Íleus/etiologia , Tempo de Internação , Complicações Pós-Operatórias/etiologia
6.
Eur Surg Res ; 62(2): 88-96, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33951660

RESUMO

INTRODUCTION: Postoperative ileus (POI) is a common complication after abdominal surgery. Until today, an evidence-based treatment of prolonged POI is still lacking, which can be attributed to the poor quality of clinical trials. Various different surrogate markers used to define POI severity are considered to be the cause of low-quality trials making it impossible to derive treatment recommendation. The SmartPill®, which is able to record pH values, temperature and pressure after ingestion, could be an ideal tool to measure transit times and peristalsis and therefore analyze POI severity. Unfortunately, the device has no approval for postoperative use due to safety concerns. The primary objective of the study is to determine safety of the SmartPill® in patients undergoing surgery. Secondary objectives were the quality of the recorded data and the suitability of the SmartPill® for analyzing intestinal motility after different surgical procedures. METHODS: The PIDuSA Study is a prospective, 2-arm, open-label trial. At the end of surgery, the SmartPill® was applied to 49 patients undergoing abdominal surgery having a high risk for impaired intestinal motility and 15 patients undergoing extra-abdominal surgery. Patients were visited daily to access safety data of the SmartPill® on the basis of adverse and serious adverse events (AEs/SAEs). Suitability and data quality were investigated by analyzing data completeness and feasibility to determine transit times and peristalsis for all sections of the gastrointestinal tract. RESULTS: In total, 179 AEs and 8 SAEs were recorded throughout the study affecting 42 patients in the abdominal (158 AEs) and 9 patients in the extra-abdominal surgery group (21 AEs, p = 0.061); none of them were device related. Primary capsule failure was observed in 5 patients, ultimately resulting in an impossibility of data analysis in only 3 patients (4.4%). 9% of the recorded data were incomplete due to the patient's incompliance in keeping the receiver close to the body. In 3 patients (4.4%), isolated small bowel transit could not be determined due to pH alterations as a result of prolonged POI. DISCUSSION: Our study demonstrates that the use of the SmartPill® is safe after surgery but requires a reasonable patient compliance to deliver meaningful data. An objective analysis of transit times and peristalsis was possible irrespective of type and site of surgery in over 95% indicating that the SmartPill® has the potential to deliver objective parameters for POI severity in future clinical trials. However, in some patients with prolonged POI, analysis of small bowel transit could be challenging.


Assuntos
Endoscopia por Cápsula/instrumentação , Motilidade Gastrointestinal , Trânsito Gastrointestinal , Trato Gastrointestinal , Humanos , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos
7.
Int J Mol Sci ; 22(13)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206766

RESUMO

Interactions between the peripheral nervous system and resident macrophages (MMs) modulate intestinal homeostatic functions. Activation of ß2-adrenergic receptors on MMs has been shown to reduce bacterial challenges. These MMs are also crucial for the development of bowel inflammation in postoperative ileus (POI), an iatrogenic, noninfectious inflammation-based motility disorder. However, the role of the sympathetic nervous system (SNS) in the immune modulation of these MMs during POI or other noninfectious diseases is largely unknown. By employing 6-OHDA-induced denervation, we investigated the changes in the muscularis externa by RNA-seq, quantitative PCR, and flow cytometry. Further, we performed transcriptional phenotyping of sorted CX3CR1+ MMs and ex vivo LPS/M-CSF stimulation on these MMs. By combining denervation with a mouse POI model, we explored distinct changes on CX3CR1+ MMs as well as in the muscularis externa and their functional outcome during POI. Our results identify SNS as an important mediator in noninfectious postoperative inflammation. Upon denervation, MMs anti-inflammatory genes were reduced, and the muscularis externa profile is shaped toward a proinflammatory status. Further, denervation reduced MMs anti-inflammatory genes also in the early phase of POI. Finally, reduced leukocyte infiltration into the muscularis led to a quicker recovery of bowel motility in the late phase of POI.


Assuntos
Pseudo-Obstrução Intestinal/imunologia , Macrófagos/imunologia , Sistema Nervoso Simpático/fisiopatologia , Animais , Receptor 1 de Quimiocina CX3C/metabolismo , Denervação/efeitos adversos , Pseudo-Obstrução Intestinal/etiologia , Leucócitos/imunologia , Fator Estimulador de Colônias de Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso/citologia
8.
Int J Mol Sci ; 22(4)2021 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-33672854

RESUMO

Enteric glial cells (EGCs) of the enteric nervous system are critically involved in the maintenance of intestinal epithelial barrier function (IEB). The underlying mechanisms remain undefined. Glial cell line-derived neurotrophic factor (GDNF) contributes to IEB maturation and may therefore be the predominant mediator of this process by EGCs. Using GFAPcre x Ai14floxed mice to isolate EGCs by Fluorescence-activated cell sorting (FACS), we confirmed that they synthesize GDNF in vivo as well as in primary cultures demonstrating that EGCs are a rich source of GDNF in vivo and in vitro. Co-culture of EGCs with Caco2 cells resulted in IEB maturation which was abrogated when GDNF was either depleted from EGC supernatants, or knocked down in EGCs or when the GDNF receptor RET was blocked. Further, TNFα-induced loss of IEB function in Caco2 cells and in organoids was attenuated by EGC supernatants or by recombinant GDNF. These barrier-protective effects were blunted when using supernatants from GDNF-deficient EGCs or by RET receptor blockade. Together, our data show that EGCs produce GDNF to maintain IEB function in vitro through the RET receptor.


Assuntos
Sistema Nervoso Entérico/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Mucosa Intestinal/metabolismo , Neuroglia/metabolismo , Animais , Células CACO-2 , Células Cultivadas , Técnicas de Cocultura , Meios de Cultivo Condicionados/farmacologia , Sistema Nervoso Entérico/efeitos dos fármacos , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Fator Neurotrófico Derivado de Linhagem de Célula Glial/farmacologia , Humanos , Mucosa Intestinal/efeitos dos fármacos , Intestino Delgado/citologia , Intestino Delgado/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Neuroglia/efeitos dos fármacos , Permeabilidade/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
9.
J Mol Cell Cardiol ; 133: 86-98, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31181227

RESUMO

BACKGROUND: Adaptation to aortic valve stenosis leads to myocardial hypertrophy, which has been associated with inflammation, fibrosis and activation of the endocannabinoid system. Since the endocannabinoid system and the CB2 receptor provide cardioprotection and modulate immune response in experimental ischemia, we investigated the role of CB2 in a mouse model of cardiac pressure overload. METHODS: Transverse aortic constriction was performed in CB2 receptor-deficient (Cnr2-/-) mice and their wild-type littermates (Cnr2+/+). After echocardiography and Millar left heart catheter hemodynamic evaluation hearts were processed for histological, cellular and molecular analyses. RESULTS: The endocannabinoid system showed significantly higher anandamide production and CB2 receptor expression in Cnr2+/+ mice. Histology showed non-confluent, interstitial fibrosis with rare small areas of cardiomyocyte loss in Cnr2+/+ mice. In contrast, extensive cardiomyocyte loss and confluent scar formation were found in Cnr2-/- mice accompanied by significantly increased apoptosis and left ventricular dysfunction when compared with Cnr2+/+ mice. The underlying cardiac maladaptation in Cnr2-/- mice was associated with significantly reduced expression of myosin heavy chain isoform beta and less production of heme oxygenase-1. Cnr2-/- hearts presented after 7 days with stronger proinflammatory response including significantly higher TNF-alpha expression and macrophage density, but lower density of CD4+ and B220+ cells. At the same time, we found increased apoptosis of macrophages and adaptive immune cells. Higher myofibroblast accumulation and imbalance in MMP/TIMP-regulation indicated adverse remodeling in Cnr2-/- mice. CONCLUSIONS: Our study provides mechanistic evidence for the role of the endocannabinoid system in myocardial adaptation to pressure overload in mice. The underlying mechanisms include production of anandamide, adaptation of contractile elements and antioxidative enzymes, and selective modulation of immune cells action and apoptosis in order to prevent the loss of cardiomyocytes.


Assuntos
Pressão Sanguínea , Miocárdio/metabolismo , Receptor CB2 de Canabinoide/deficiência , Disfunção Ventricular/etiologia , Disfunção Ventricular/fisiopatologia , Animais , Biomarcadores , Cardiomegalia/etiologia , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Cardiomegalia/fisiopatologia , Modelos Animais de Doenças , Endocanabinoides/metabolismo , Feminino , Imunofluorescência , Genótipo , Hemodinâmica , Imuno-Histoquímica , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Camundongos Knockout , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Estresse Oxidativo , Disfunção Ventricular/metabolismo , Disfunção Ventricular/patologia , Remodelação Ventricular
10.
Int J Colorectal Dis ; 34(3): 417-422, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30519842

RESUMO

PURPOSE: Postoperative ileus (POI) is a common complication after abdominal surgery. Invasive stimulation of the cervical vagus nerve is known to reduce inflammatory response and ameliorated POI after surgery in a mouse model. However, the transcutaneous vagus nerve stimulation (tVNS) is a possible non-invasive approach. In this clinical study, we aimed to investigate the effect of tVNS on the activation of the stomach muscle in humans. METHODS: Patients requiring open laparotomy were screened for this prospective proof of concept clinical study. After open laparotomy, muscle activity of the stomach was measured by a free running electromyography (EMG) before and during tVNS on the ear. Frequency and amplitude of compound gastric action potentials were the electrophysiological parameters we assessed to reveal the changes in electro motor gastric activity. Gastrin levels as a surrogate marker for vagus nerve activation was analyzed before, 1 and 3 h after tVNS. RESULTS: Fourteen patients were included, no severe adverse events and no medical device related adverse events occurred. tVNS led to significant reduction of action potential frequency and significant elevation of action potential amplitude in the stomach compared to control. Gastrin levels were significantly elevated 3 h after tVNS compared to levels before tVNS. CONCLUSION: Application of tVNS is a safe and feasible procedure during surgical intervention. Our results provide evidence that tVNS activates efferent visceral vagal fibers. Therefore, this low risk and easy to perform method could be useful to prevent postoperative ileus. CLINICAL TRIAL REGISTER NUMBER: DRKS00013340.


Assuntos
Trato Gastrointestinal/fisiologia , Músculos/fisiologia , Estimulação Elétrica Nervosa Transcutânea , Estimulação do Nervo Vago , Pressão Sanguínea , Eletromiografia , Estudos de Viabilidade , Feminino , Gastrinas/sangue , Frequência Cardíaca , Humanos , Laparotomia , Masculino , Pessoa de Meia-Idade , Estimulação Elétrica Nervosa Transcutânea/efeitos adversos , Resultado do Tratamento , Estimulação do Nervo Vago/efeitos adversos
11.
Pflugers Arch ; 469(3-4): 541-552, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28236119

RESUMO

Macrophages reside in a dense cellular network in the intestinal muscularis externa, and there is emerging evidence that the functionality of these cells determines the local microenvironment. Inflammatory responses during intestinal diseases change the homeostatic functionality of these cells causing inflammation and intestinal dysmotility. Such disturbances are not only induced by a change in the cellular composition in the intestinal muscularis but also by an altered crosstalk with the peripheral and central nervous system. In this review, we summarize the role of muscularis macrophages in the intestine in homeostasis and inflammation. We compare the functionality, the phenotype, and the origin of muscularis macrophages to their neighboring counterparts within the different layers of the intestine. We outline the cellular crosstalk with the enteric and the peripheral nervous system and summarize the current therapeutic approaches to modulate the functionality of these phagocytes.


Assuntos
Inflamação/patologia , Intestinos/patologia , Intestinos/fisiologia , Macrófagos/patologia , Macrófagos/fisiologia , Animais , Homeostase/fisiologia , Humanos , Músculo Liso/patologia , Músculo Liso/fisiologia
12.
Langenbecks Arch Surg ; 402(1): 115-122, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27585678

RESUMO

PURPOSE: In recent years, multimodal treatment approaches have led to an increased median survival time of patients with colorectal liver metastases. In particular, this results from new perioperative chemotherapy regimens, which in turn are accompanied by an increased risk of perioperative bleeding and/or liver failure due to the hepatotoxic side effects. Nineteen to 58 % of patients treated with oxaliplatin develop sinusoidal obstruction syndrome (SOS). The influence of preexisting SOS on liver surgery remains controversial. METHODS: Animals were operated 4 days after SOS induction with monocrotaline and received either vascular occlusion in the form of Pringle maneuver (PM) or hepatectomy (LR; 70 %) or a combination of both (LR + PM). Postoperative liver function was assessed by determination of liver enzyme levels, bile production, and tissue oxygen saturation. RESULTS: Preexisting SOS impaired morbidity after liver resection, reflected by elevated liver enzyme levels, reduced bile secretion, and low liver tissue oxygenation levels. Mortality was increased by up to 25 %. Additional ischemia in the form of PM showed no further impact in the LR ± PM group compared to LR alone. CONCLUSION: PM without LR results in high enzyme distribution in the SOS group. SOS significantly affects the outcome after liver resection in our experimental rat model only without PM and showed no protective effect in ischemia in the form of PM.


Assuntos
Hepatectomia , Hepatopatia Veno-Oclusiva/cirurgia , Animais , Antineoplásicos/efeitos adversos , Neoplasias Colorretais/patologia , Terapia Combinada , Modelos Animais de Doenças , Hepatopatia Veno-Oclusiva/etiologia , Hepatopatia Veno-Oclusiva/patologia , Hipóxia , Testes de Função Hepática , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Masculino , Monocrotalina , Compostos Organoplatínicos/efeitos adversos , Oxaliplatina , Ratos , Ratos Sprague-Dawley
13.
Langenbecks Arch Surg ; 402(4): 625-636, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27761714

RESUMO

PURPOSE: Laparoscopic surgery (LS) has proved superior compared to conventional surgery (CS) regarding morbidity, length of hospital stay, rate of wound infection and time until recovery. An improved preservation of the postoperative immune function is assumed to contribute to these benefits though the role of the local peritoneal immune response is still poorly understood. Our study investigates the peritoneal immune response subsequent to abdominal surgery and compares it between laparoscopic and conventional surgery to find an immunological explanation for the clinically proven benefits of LS. METHODS: Wistar rats (N = 140) underwent laparoscopic cecum resection (LCR; N = 28), conventional cecum resection (CCR; N = 28), laparoscopic sham operation (LSO; N = 28), conventional sham operation (CSO; N = 28), or no surgical treatment (CTRL; N = 28). Postoperatively, peritoneal lavages were performed, leukocytes isolated and analyzed regarding immune function and phagocytosis activity. RESULTS: Immune function was inhibited postoperatively in animals undergoing LCR or CCR compared to CTRL reflected by a lower TNF-α (CTRL 3956.65 pg/ml, LCR 2018.48 pg/ml (p = 0.023), CCR 2793.78 pg/ml (n.s.)) and IL-6 secretion (CTRL 625.84 pg/ml, LCR 142.84 pg/ml (p = 0.009), CCR 169.53 pg/ml (p = 0.01)). Phagocytosis was not affected in rats undergoing any kind of surgery compared to CTRL. Neither cytokine secretion nor phagocytosis activity differed significantly between laparoscopic and conventional surgery. CONCLUSIONS: According to our findings the benefits associated with LS compared to CS cannot be explained by differences in the postoperative peritoneal innate immune response. Further studies are needed to elucidate the causes for a more favorable postoperative outcome in patients after LS compared to CS.


Assuntos
Ceco/cirurgia , Imunidade Inata/fisiologia , Laparoscopia , Peritônio/imunologia , Animais , Citocinas , Feminino , Masculino , Lavagem Peritoneal , Fagocitose , Ratos , Ratos Wistar
14.
EMBO J ; 31(1): 201-13, 2012 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-22036947

RESUMO

Early during Gram-negative sepsis, excessive release of pro-inflammatory cytokines can cause septic shock that is often followed by a state of immune paralysis characterized by the failure to mount adaptive immunity towards secondary microbial infections. Especially, the early mechanisms responsible for such immune hypo-responsiveness are unclear. Here, we show that TLR4 is the key immune sensing receptor to initiate paralysis of T-cell immunity after bacterial sepsis. Downstream of TLR4, signalling through TRIF but not MyD88 impaired the development of specific T-cell immunity against secondary infections. We identified type I interferon (IFN) released from splenic macrophages as the critical factor causing T-cell immune paralysis. Early during sepsis, type I IFN acted selectively on dendritic cells (DCs) by impairing antigen presentation and secretion of pro-inflammatory cytokines. Our results reveal a novel immune regulatory role for type I IFN in the initiation of septic immune paralysis, which is distinct from its well-known immune stimulatory effects. Moreover, we identify potential molecular targets for therapeutic intervention to overcome impairment of T-cell immunity after sepsis.


Assuntos
Imunidade Adaptativa , Interferon Tipo I/metabolismo , Macrófagos/metabolismo , Sepse/imunologia , Baço/metabolismo , Animais , Células Dendríticas/metabolismo , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/metabolismo , Sepse/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo
15.
Am J Physiol Gastrointest Liver Physiol ; 311(5): G920-G933, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27514477

RESUMO

The cholinergic anti-inflammatory pathway reduces systemic tumor necrosis factor (TNF) via acetylcholine-producing memory T cells in the spleen. These choline acetyltransferase (ChAT)-expressing T cells are also found in the intestine, where their function is unclear. We aimed to characterize these cells in mouse and human intestine and delineate their function. We made use of the ChAT-enhanced green fluorescent protein (eGFP) reporter mice. CD4Cre mice were crossed to ChATfl/fl mice to achieve specific deletion of ChAT in CD4+ T cells. We observed that the majority of ChAT-expressing T cells in the human and mouse intestine have characteristics of Th17 cells and coexpress IL17A, IL22, and RORC The generation of ChAT-expressing T cells was skewed by dendritic cells after activation of their adrenergic receptor ß2 To evaluate ChAT T cell function, we generated CD4-specific ChAT-deficient mice. CD4ChAT-/- mice showed a reduced level of epithelial antimicrobial peptides lysozyme, defensin A, and ang4, which was associated with an enhanced bacterial diversity and richness in the small intestinal lumen in CD4ChAT-/- mice. We conclude that ChAT-expressing T cells in the gut are stimulated by adrenergic receptor activation on dendritic cells. ChAT-expressing T cells may function to mediate the host AMP secretion, microbial growth and expansion.


Assuntos
Acetilcolina/metabolismo , Defensinas/metabolismo , Microbioma Gastrointestinal/fisiologia , Mucosa Intestinal/metabolismo , Muramidase/metabolismo , Ribonuclease Pancreático/metabolismo , Linfócitos T/metabolismo , Animais , Colina O-Acetiltransferase/genética , Colina O-Acetiltransferase/metabolismo , Humanos , Camundongos , Camundongos Knockout , Camundongos Transgênicos
16.
Gastroenterology ; 146(1): 176-87.e1, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24067878

RESUMO

BACKGROUND & AIMS: Postoperative ileus (POI) is a common consequence of abdominal surgery that increases the risk of postoperative complications and morbidity. We investigated the cellular mechanisms and immune responses involved in the pathogenesis of POI. METHODS: We studied a mouse model of POI in which intestinal manipulation leads to inflammation of the muscularis externa and disrupts motility. We used C57BL/6 (control) mice as well as mice deficient in Toll-like receptors (TLRs) and cytokine signaling components (TLR-2(-/-), TLR-4(-/-), TLR-2/4(-/-), MyD88(-/-), MyD88/TLR adaptor molecule 1(-/-), interleukin-1 receptor [IL-1R1](-/-), and interleukin (IL)-18(-/-) mice). Bone marrow transplantation experiments were performed to determine which cytokine receptors and cell types are involved in the pathogenesis of POI. RESULTS: Development of POI did not require TLRs 2, 4, or 9 or MyD88/TLR adaptor molecule 2 but did require MyD88, indicating a role for IL-1R1. IL-1R1(-/-) mice did not develop POI; however, mice deficient in IL-18, which also signals via MyD88, developed POI. Mice given injections of an IL-1 receptor antagonist (anakinra) or antibodies to deplete IL-1α and IL-1ß before intestinal manipulation were protected from POI. Induction of POI activated the inflammasome in muscularis externa tissues of C57BL6 mice, and IL-1α and IL-1ß were released in ex vivo organ bath cultures. In bone marrow transplantation experiments, the development of POI required activation of IL-1 receptor in nonhematopoietic cells. IL-1R1 was expressed by enteric glial cells in the myenteric plexus layer, and cultured primary enteric glia cells expressed IL-6 and the chemokine monocyte chemotactic protein 1 in response to IL-1ß stimulation. Immunohistochemical analysis of human small bowel tissue samples confirmed expression of IL-1R1 in the ganglia of the myenteric plexus. CONCLUSIONS: IL-1 signaling, via IL-1R1 and MyD88, is required for development of POI after intestinal manipulation in mice. Agents that interfere with the IL-1 signaling pathway are likely to be effective in the treatment of POI.


Assuntos
Motilidade Gastrointestinal/imunologia , Íleus/imunologia , Interleucina-1/imunologia , Músculo Liso/imunologia , Fator 88 de Diferenciação Mieloide/imunologia , Plexo Mientérico/imunologia , Neuroglia/imunologia , Complicações Pós-Operatórias/imunologia , Receptores Tipo I de Interleucina-1/imunologia , Animais , Modelos Animais de Doenças , Íleus/metabolismo , Interleucina-1/metabolismo , Interleucina-18/genética , Interleucina-18/imunologia , Interleucina-18/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Músculo Liso/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Plexo Mientérico/metabolismo , Neuroglia/metabolismo , Complicações Pós-Operatórias/metabolismo , Receptores Tipo I de Interleucina-1/genética , Receptores Tipo I de Interleucina-1/metabolismo , Transdução de Sinais , Receptores Toll-Like/genética , Receptores Toll-Like/imunologia , Receptores Toll-Like/metabolismo
17.
Front Immunol ; 15: 1401751, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39119341

RESUMO

Introduction: Enteric glial cells are important players in the control of motility, intestinal barrier integrity and inflammation. During inflammation, they switch into a reactive phenotype enabling them to release inflammatory mediators, thereby shaping the inflammatory environment. While a plethora of well-established in vivo models exist, cell culture models necessary to decipher the mechanistic pathways of enteric glial reactivity are less well standardized. In particular, the composition of extracellular matrices (ECM) can massively affect the experimental outcome. Considering the growing number of studies involving primary enteric glial cells, a better understanding of their homeostatic and inflammatory in vitro culture conditions is needed. Methods: We examined the impact of different ECMs on enteric glial culture purity, network morphology and immune responsiveness. Therefore, we used immunofluorescence and brightfield microscopy, as well as 3' bulk mRNA sequencing. Additionally, we compared cultured cells with in vivo enteric glial transcriptomes isolated from Sox10iCreERT2Rpl22HA/+ mice. Results: We identified Matrigel and laminin as superior over other coatings, including poly-L-ornithine, different lysines, collagens, and fibronectin, gaining the highest enteric glial purity and most extended glial networks expressing connexin-43 hemichannels allowing intercellular communication. Transcriptional analysis revealed strong similarities between enteric glia on Matrigel and laminin with enrichment of gene sets supporting neuronal differentiation, while cells on poly-L-ornithine showed enrichment related to cell proliferation. Comparing cultured and in vivo enteric glial transcriptomes revealed a 50% overlap independent of the used coating substrates. Inflammatory activation of enteric glia by IL-1ß treatment showed distinct coating-dependent gene expression signatures, with an enrichment of genes related to myeloid and epithelial cell differentiation on Matrigel and laminin coatings, while poly-L-ornithine induced more gene sets related to lymphocyte differentiation. Discussion: Together, changes in morphology, differentiation and immune activation of primary enteric glial cells proved a strong effect of the ECM. We identified Matrigel and laminin as pre-eminent substrates for murine enteric glial cultures. These new insights will help to standardize and improve enteric glial culture quality and reproducibility between in vitro studies in the future, allowing a better comparison of their functional role in enteric neuroinflammation.


Assuntos
Matriz Extracelular , Homeostase , Laminina , Neuroglia , Animais , Matriz Extracelular/metabolismo , Neuroglia/metabolismo , Neuroglia/imunologia , Camundongos , Laminina/metabolismo , Sistema Nervoso Entérico/metabolismo , Sistema Nervoso Entérico/imunologia , Células Cultivadas , Combinação de Medicamentos , Colágeno/metabolismo , Camundongos Endogâmicos C57BL , Proteoglicanas/metabolismo
18.
Nat Commun ; 15(1): 6079, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030280

RESUMO

Enteric glia have been recently recognized as key components of the colonic tumor microenvironment indicating their potential role in colorectal cancer pathogenesis. Although enteric glia modulate immune responses in other intestinal diseases, their interaction with the colorectal cancer immune cell compartment remains unclear. Through a combination of single-cell and bulk RNA-sequencing, both in murine models and patients, here we find that enteric glia acquire an immunomodulatory phenotype by bi-directional communication with tumor-infiltrating monocytes. The latter direct a reactive enteric glial cell phenotypic and functional switch via glial IL-1R signaling. In turn, tumor glia promote monocyte differentiation towards pro-tumorigenic SPP1+ tumor-associated macrophages by IL-6 release. Enteric glia cell abundancy correlates with worse disease outcomes in preclinical models and colorectal cancer patients. Thereby, our study reveals a neuroimmune interaction between enteric glia and tumor-associated macrophages in the colorectal tumor microenvironment, providing insights into colorectal cancer pathogenesis.


Assuntos
Neoplasias Colorretais , Neuroglia , Transdução de Sinais , Microambiente Tumoral , Animais , Neoplasias Colorretais/patologia , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/genética , Humanos , Microambiente Tumoral/imunologia , Neuroglia/metabolismo , Camundongos , Macrófagos/metabolismo , Macrófagos/imunologia , Receptores de Interleucina-1/metabolismo , Receptores de Interleucina-1/genética , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/metabolismo , Interleucina-6/metabolismo , Monócitos/metabolismo , Monócitos/imunologia , Camundongos Endogâmicos C57BL , Comunicação Celular , Diferenciação Celular , Linhagem Celular Tumoral , Feminino
19.
Cell Physiol Biochem ; 32(5): 1362-73, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24280834

RESUMO

BACKGROUND: Postoperative ileus (POI) is an iatrogenic complication of abdominal surgery, mediated by a severe inflammation of the muscularis externa (ME). We demonstrated that orally applicated CPSI-2364 prevents POI in rodents by blockade of p38 MAPK pathway and abrogation of NO production in macrophages. In the present experimental swine study we compared the effect of orally and intravenously administered CPSI-2364 on POI and examined CPSI-2364 effect on anastomotic healing. METHODS: CPSI-2364 was administered preoperatively via oral or intravenous route. POI was induced by intestinal manipulation of the small bowel. ME specimens were examined by quantitative PCR for CCL2 chemokine gene expression and myeloperoxidase activity. Functional analyzes included measurement of ileal smooth-muscle ex vivo contractility, in vivo intestinal and colonic transit. Furthermore, anastomotic healing of a rectorectostomy after CPSI-2364 treatment was assessed by perianastomotic hydroxyproline concentration, a histochemically evaluated healing score and anastomotic bursting pressure (ABP). RESULTS: CPSI-2364 abolished inflammation of the ME and improved postoperative smooth muscle contractility and intestinal transit independently of its application route. Hydroxyproline concentration and ABP measurement revealed no wound healing disturbances after oral or intravenous CPSI-2364 treatment whereas histological scoring demonstrated delayed anastomotic healing after intravenous treatment. CONCLUSION: CPSI-2364 effectively prevents POI in swine independently of its application route. Impairment of anastomotic healing could be observed after intravenous but not oral preoperative CPSI-2364 treatment. Subsumed, an oral preoperative administration of CPSI-2364 appears to be a safe and efficient strategy for prophylaxis of POI.


Assuntos
Hidrazonas/farmacologia , Íleus/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Administração Intravenosa , Administração Oral , Anastomose Cirúrgica , Animais , Hidrazonas/administração & dosagem , Hidroxiprolina/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiopatologia , Óxido Nítrico/metabolismo , Reto/efeitos dos fármacos , Reto/cirurgia , Suínos , Cicatrização/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
20.
Pathobiology ; 80(2): 102-10, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23108005

RESUMO

BACKGROUND/AIMS: Ischemia reperfusion (I/R) injury after small bowel transplantation leads to inflammatory reactions and loss of structural integrity with subsequent graft contractile dysfunction in the early postoperative phase. The natural tetrahydropyrimidine ectoine (1-,4-,5-,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid; THP) protects the ileal mucosa and muscularis against effects of I/R injury in an experimental model of isolated graft reperfusion. The effects of THP treatment were evaluated in an established experimental intestinal transplant model. METHODS: Isogenic, orthotopic small bowel transplantation was performed in Lewis rats (6 h cold ischemia time). Perioperative THP treatment (intraluminal/intravascular) groups were compared to vehicle-treated animals (after 3 and 24 h) and non-transplanted controls (n = 5/group). Park's score defined the effects of I/R injury. The infiltration of neutrophils, monocytes and macrophages, mRNA expression of IL-6 and TNF-α, serum levels of IL-6 and NO and smooth muscle contractility were evaluated. RESULTS: Improved graft outcome after intraluminal and intravascular THP treatment was defined by considerably ameliorated neutrophil infiltration and less histological signs of I/R injury (p ≤ 0.05). In the presence of THP, mRNA expression of IL-6 and TNF-α and IL-6 and NO serum levels were reduced and smooth muscle function was improved. CONCLUSION: THP treatment offers protection against the effects of I/R injury in intestinal transplantation in vivo, however, only as supplementary treatment option.


Assuntos
Diamino Aminoácidos/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Intestino Delgado/transplante , Traumatismo por Reperfusão/prevenção & controle , Animais , Interleucina-6/genética , Intestino Delgado/fisiopatologia , Macrófagos/imunologia , Masculino , Monócitos/imunologia , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Infiltração de Neutrófilos , Neutrófilos/imunologia , Óxido Nítrico/metabolismo , Complicações Pós-Operatórias , Ratos , Ratos Endogâmicos Lew , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/fisiopatologia , Transplante Isogênico , Resultado do Tratamento , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética
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