sirolimus has been researched along with Sepsis* in 18 studies
18 other study(ies) available for sirolimus and Sepsis
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The Polo-Like Kinase 1-Mammalian Target of Rapamycin Axis Regulates Autophagy to Prevent Intestinal Barrier Dysfunction During Sepsis.
The intestines play a crucial role in the development of sepsis. The balance between autophagy and apoptosis in intestinal epithelial cells is dynamic and determines intestinal permeability. The present study focused on the potential role of autophagy in sepsis-induced intestinal barrier dysfunction and explored the mechanisms in vivo and in vitro. Excessive apoptosis in intestinal epithelia and a disrupted intestinal barrier were observed in septic mice. Promoting autophagy with rapamycin reduced intestinal epithelial apoptosis and restored intestinal barrier function, presenting as decreased serum diamine oxidase (DAO) and fluorescein isothiocyanate-dextran 40 (FD40) levels and increased expression of zonula occludens-1 (ZO-1) and Occludin. Polo-like kinase 1 (PLK1) knockdown in mice ameliorated intestinal epithelial apoptosis and the intestinal barrier during sepsis, whereas these effects were reduced with chloroquine and enhanced with rapamycin. PLK1 also promoted cell autophagy and improved lipopolysaccharide-induced apoptosis and high permeability in vitro. Moreover, PLK1 physically interacted with mammalian target of rapamycin (mTOR) and participated in reciprocal regulatory crosstalk in intestinal epithelial cells during sepsis. This study provides novel insight into the role of autophagy in sepsis-induced intestinal barrier dysfunction and indicates that the PLK1-mTOR axis may be a promising therapeutic target for sepsis. Topics: Animals; Autophagy; Intestinal Diseases; Intestinal Mucosa; Mammals; Mice; Polo-Like Kinase 1; Sepsis; Sirolimus; TOR Serine-Threonine Kinases | 2023 |
Metformin Alleviates Sepsis-Associated Myocardial Injury by Enhancing AMP-Activated Protein Kinase/Mammalian Target of Rapamycin Signaling Pathway-Mediated Autophagy.
Sepsis-associated myocardial injury is one of the main causes of death in intensive care units, and current clinical treatments have not been satisfactory. Therefore, finding an effective intervention is an urgent requirement. Metformin, an anti-type 2 diabetes drug, has been reported to be an autophagic activator agent that confers protection in some diseases. However, it is unclear whether it can provide defense against sepsis-associated myocardial injury. In this study, we investigated the cardioprotective effects of metformin pretreatment against lipopolysaccharide (LPS)-induced myocardial injury in C57BL/6J mice or H9c2 cells and the possible underlying mechanisms. Metformin was administered at a dose of 100 mg/kg for a week before LPS intraperitoneal injection. Twenty-four hours after LPS intervention, echocardiographic evaluation, reactive oxygen species measurement, Hoechst staining, western blotting, hematoxylin and eosin staining, and enzyme-linked immunosorbent assay were performed. Inhibitors of autophagy and AMP-activated protein kinase (AMPK) were used to further clarify the mechanisms involved. Metformin pretreatment effectively attenuated cardiac dysfunction, reduced the levels of myocardial enzymes, and alleviated cardiac hydroncus in LPS-treated mice. In addition, metformin restored the LPS-disrupted antioxidant defense and activated LPS-reduced autophagy by modulating the AMPK/mammalian target of rapamycin (AMPK/mTOR) pathway both in vivo and in vitro. The antioxidant effects of metformin on cardiomyocytes were abolished by the autophagy inhibitor 3-methyladenine (3-MA). Treatment with compound C, an AMPK inhibitor, reversed the metformin-induced autophagy in LPS-treated H9c2 cells. In conclusion, metformin pretreatment alleviates LPS-induced myocardial injury by activating AMPK/mTOR pathway-mediated autophagy. Topics: AMP-Activated Protein Kinases; Animals; Autophagy; Lipopolysaccharides; Mammals; Metformin; Mice; Mice, Inbred C57BL; Sepsis; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases | 2023 |
Hydrogen sulfide attenuates ferroptosis and stimulates autophagy by blocking mTOR signaling in sepsis-induced acute lung injury.
Sepsis often leads to multiple organ failure or even death and is a significant health problem that contributes to a heavy economic burden. The lung is the first organ to be affected by sepsis. Presently, there is no specific drug or method to treat sepsis and sepsis-induced acute lung injury (ALI). H2S, along with CO and NO, is a physiological gas that acts as a signaling molecule and plays an active role in fighting various lung infections. GYY4137 is a novel H2S donor that is stable in vivo and in vitro. However, particularly in the context of ferroptosis, GYY4137 affects cecal ligation and puncture (CLP)-induced ALI by a mechanism that is not understood. Ferroptosis is a new form of cell necrosis. The primary mechanism is the accumulation of cellular lipid ROS in an iron-dependent manner. The principal objective of this project was to investigate the effects of GYY4137 on ferroptosis and autophagy in a mouse model of sepsis-induced ALI. We divided the experimental mice randomly into 5 groups: (1) sham group; (2) CLP group; (3) CLP + DMSO group: (4) CLP + GYY4137 (25 mg/kg) group; and (5) CLP + GYY4137 (50 mg/kg) group. (6) CLP + Rapamycin (2.0 mg/Kg) group. (7) CLP + Chloroquine (80 mg/Kg) group. (8) the Chloroquine (80 mg/Kg) + GYY (50 mg/Kg) group. The findings showed that GYY4137 significantly protected against CLP-induced ALI by improving sepsis-induced lung histopathological changes, diminishing lung tissue damage, ameliorating oxidative stress, and attenuating the severity of lung injury in mice. In this study, we found that GYY4137 could alleviate septicemia-induced ferroptosis in ALI by increasing the expression of GPx4 and SLC7A11 in lung tissue after CLP. One unexpected finding was the extent to which the levels of ferritin and ferritin light chain increased after CLP, which may be a compensatory mechanism for storing abnormally increased iron. We also found that the expression of p-mTOR, P62, and Beclin1 was significantly increased and that LC3II/LC3I declined after LPS stimulation, but the effect was inhibited by treatment with GYY4137, indicating that GYY4137 could inhibit the activation of autophagy in sepsis-induced ALI by blocking mTOR signaling. Topics: Acute Lung Injury; Animals; Autophagy; Cecum; Cell Line; Disease Models, Animal; Ferroptosis; Hydrogen Sulfide; Ligation; Lung; Male; Mice; Mice, Inbred C57BL; Morpholines; Multiple Organ Failure; Organothiophosphorus Compounds; RAW 264.7 Cells; Sepsis; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases | 2022 |
mTOR deletion ameliorates CD4 + T cell apoptosis during sepsis by improving autophagosome-lysosome fusion.
Autophagy dysfunction contributes to CD4 + T cell apoptosis during sepsis leading to impairment of adaptive immunity. However, the underlying mechanism is unclear. The mammalian target of rapamycin (mTOR) pathway modulates CD4 + T cell survival during sepsis through mechanisms that are not fully understood. We developed a mouse model of sepsis through cecal ligation and puncture (CLP) to investigate dynamic changes in autophagy in CD4 + T cells. We used T cell specific-mTOR/tuberous sclerosis complex 1 (TSC1)-knockout mice to explore the roles of the mTOR pathway in modulating autophagy during sepsis. We observed reduced fusion of autophagosomes with lysosomes in the CD4 + T cells of CLP mice, which may represent a characteristic feature of autophagy dysfunction. Deletion of mTOR relieved autophagosome-lysosome fusion dysfunction and ameliorated apoptosis of CD4 + T cells in CLP mice, but this rescued phenotype was abolished by treatment with bafilomycin A1, a specific A-L fusion inhibitor. We further explored the underlying molecular mechanism and found that phosphorylation levels of transcription factor EB were significant higher in CLP mice and that expression of A-L fusion protein SNAREs were restricted, both of which were ameliorated by mTOR deletion. Taken together, these results suggest that the mTOR pathway plays a critical role in regulation of CD4 + T-cell apoptosis during sepsis, partly through regulation of A-L fusion-related protein transcription. Topics: Animals; Apoptosis; Autophagosomes; Autophagy; Lysosomes; Mammals; Mice; Sepsis; Sirolimus; TOR Serine-Threonine Kinases | 2022 |
[Rapamycin alleviates cognitive impairment in mice with sepses-associated encephalopathy by promoting autophagy].
Objective To investigate the role of rapamycin in alleviating cognitive dysfunction by promoting autophagy in mice with sepsis-associated encephalopathy (SAE). Methods The model of SAE mice was established by caecal ligation and perforation (CLP). Murine sepsis score (MSS) was used to evaluate the severity of sepsis in SAE mice. And the cognitive function was tested by the contextual fear conditioning test. The expression levels of microtubule-associated protein 1 light chain 3 (LC3) and P62 in the hippocampus of the SAE mice were detected by Western blot analysis. Furthermore, the expression and distribution of LC3 in the hippocampal neurons were observed by immunofluorescence. Results The mortality of CLP-induced mice reached 41.7% with 14 days after the procedure, and significant cognitive dysfunction was detected in the surviving mice. Meanwhile, autophagy in the hippocampal tissue was impaired 14 days after CLP. The cognitive dysfunction of SAE mice was alleviated by promoting autophagy via rapamycin. Conclusion Rapamycin alleviated the cognitive dysfunction of SAE mice by promoting autophagy in the hippocampal neurons. Topics: Animals; Autophagy; Cognitive Dysfunction; Hippocampus; Mice; Mice, Inbred C57BL; Sepsis; Sepsis-Associated Encephalopathy; Sirolimus | 2022 |
Rapamycin Inhibited Pyroptosis and Reduced the Release of IL-1
Pyroptosis, an inflammatory form of programmed cell death, is the initiating event of sepsis and results in immune imbalance by releasing IL-1 Topics: Autophagy; Caspase 1; Gene Expression Regulation; Human Umbilical Vein Endothelial Cells; Humans; Interleukin-18; Interleukin-1beta; Intracellular Signaling Peptides and Proteins; Lipopolysaccharides; Macrophages; Phosphate-Binding Proteins; Pyroptosis; Sepsis; Sirolimus; THP-1 Cells | 2020 |
Mitochondrial dysfunction is associated with long-term cognitive impairment in an animal sepsis model.
Topics: Animals; Autophagy; Brain; Cognitive Dysfunction; Disease Models, Animal; Male; Mitochondria; Mitochondrial Dynamics; Rats, Wistar; Rilmenidine; Rosiglitazone; Sepsis; Sirolimus; Survival Analysis; Up-Regulation | 2019 |
Enhancing Autophagy Protects Against Sepsis-Induced Neuromuscular Dysfunction Associated with Qualitative Changes to Acetylcholine Receptors.
Sepsis-induced myopathy is a heavy burden for patients during respiratory failure as well as after discharge, which could be characterized with qualitative changes to nAChR in a rat model of sepsis, regulated by NRG-1. Autophagy is an innate immune defense mechanism against microbial challenges. We found neuromuscular dysfunction in anterior tibial muscle of male Sprague-Dawley rats 24 h after cecal ligation and puncture (CLP). CLP resulted in increased systemic and local inflammation in anterior tibial muscle tissue. The start-up phase of autophagy, as measured by LC3II, was activated immediately after CLP and continued until 24 h; the degradation phase was suppressed until 24 h, after a brief increase at 4 h (revealed by p62). NRG-1 first increased, and then decreased to a level lower than that in the sham group. Meanwhile, expression of γ- and α7- acetylcholine receptors was detected at 8 and 16 h after CLP; levels increased continuously until 24 h. Subsequently, we investigated the significance of autophagy in CLP-induced neuromuscular dysfunction by treatment with rapamycin or 3-methyladenine, which were classical pharmaceuticals for enhancing or suppressing autophagy. Rapamycin activated autophagy, limited the CLP-induced systemic pro-inflammatory response and blood bacterial load without affecting local inflammatory response, upregulated NRG-1, downregulated γ- and α7-acetylcholine receptors, and improved 7-day neuromuscular function and survival rate. In contrast, 3-methyladenine enhanced local inflammatory response, suppressed autophagy, worsened 7-day neuromuscular function. We conclude that impaired autophagy may contribute to sepsis-induced neuromuscular dysfunction in young male rats. Enhancing autophagy with rapamycin alleviated qualitative changes to acetylcholine receptors without triggering local anti-inflammatory response and improved anterior tibial muscle function in septic early phase (24 h) as well as in septic chronic phase (7d). Enhancing autophagy soon after sepsis is a potential strategy for treatment of sepsis-induced myopathy. Topics: Adenine; Animals; Autophagy; Cecum; Ligation; Male; Punctures; Rats; Rats, Sprague-Dawley; Receptors, Cholinergic; Sepsis; Sirolimus; Sphingosine-1-Phosphate Receptors | 2019 |
Impaired cellular energy metabolism in cord blood macrophages contributes to abortive response toward inflammatory threats.
Neonatal sepsis is characterized by hyperinflammation causing enhanced morbidity and mortality compared to adults. This suggests differences in the response towards invading threats. Here we investigate activated cord blood macrophages (CBMΦ) in comparison to adult macrophages (PBMΦ), indicating incomplete interferon gamma (IFN-γ) and interleukin 10 (IL-10)-induced activation of CBMΦ. CBMΦ show reduced expression of phagocytosis receptors and cytokine expression in addition to altered energy metabolism. In particular, IFN-γ as well as IL-10-activated CBMΦ completely fail to increase glycolysis and furthermore show reduced activation of the mTOR pathway, which is important for survival in sepsis. MTOR inhibition by rapamycin equalizes cytokine production in CBMΦ and PBMΦ. Finally, incubation of PBMΦ with cord blood serum or S100A8/A9, which is highly expressed in neonates, suppresses mTOR activation, prevents glycolysis and the expression of an PBMΦ phenotype. Thus, a metabolic alteration is apparent in CBMΦ, which might be dependent on S100A8/A9 expression. Topics: Adult; Age Factors; Calgranulin A; Calgranulin B; Cell Differentiation; Cells, Cultured; Cytotoxicity, Immunologic; Energy Metabolism; Fetal Blood; Glycolysis; Healthy Volunteers; Humans; Infant, Newborn; Interferon-gamma; Interleukin-10; Macrophages; Primary Cell Culture; Sepsis; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases | 2019 |
Protective effects of rapamycin induced autophagy on CLP septic mice.
Sepsis is a life-threatening condition that may develop to multiple organ failure and septic shock. Autophagy is considered to play an important role in the regulation of inflammation. The present study aims to investigate the protective role of mTORC1 inhibitor, rapamycin, on septic death using cecal ligation and puncture (CLP) mice model. Here, results showed that pretreatment with rapamycin reduced the pyroptosis of peritoneal macrophages stimulated by cecal contents and the release of inflammatory factors such as interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α); In septic mice, rapamycin treatment decreased the activation of inflammasome in lung, and alleviated the pathological injuries in lung, liver and spleen tissues during acute stage of sepsis. Treatment of rapamycin rescued animals from septic death significantly. Our results indicated that activation of autophagy is a potential strategy to regulate the excessive inflammation in acute stage of sepsis. Topics: Animals; Autophagy; Cecum; Cytokines; Disease Models, Animal; Inflammasomes; Inflammation; Ligation; Lung; Macrophages, Peritoneal; Male; Mice; Mice, Inbred C57BL; Sepsis; Sirolimus | 2019 |
Sepsis-Induced Myocardial Dysfunction and Mammalian Target of Rapamycin Signalling Pathways.
Topics: Cardiomyopathies; Humans; Sepsis; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases | 2019 |
Initial pathological responses of second-generation everolimus-eluting stents implantation in Japanese coronary arteries: Comparison with first-generation sirolimus-eluting stents.
The clinical benefit of second-generation drug-eluting stents (2nd DES) has been established, compared to first-generation drug-eluting stents (1st DES). However, pathological response after 2nd DES implantation remains unclear, particularly in the Japanese population.. Using specimens obtained by autopsy, we compared the histology between 2nd DES (41 sections) and 1st DES (38 sections) lesions within 1 year after stent implantation to evaluate early tissue reaction in Japanese patients. Stent segments were fixed with 10% buffered formalin and embedded in plastic, followed by hematoxylin-eosin and Masson's trichrome staining. Ratio of covered stent struts was calculated, and the area of fibrin deposition was morphometrically evaluated. The degree of inflammation around struts was examined semi-quantitatively (score 0-3).. The ratio of covered struts and mean fibrin area of 2nd DES were 0.69±0.05 and 658.0±173.4μm. Histopathological analysis showed advanced healing process in 2nd DES compared with 1st DES lesions. These results are consistent with clinical beneficial outcome of 2nd DES implantation. Topics: Aged; Aneurysm, Ruptured; Colitis, Ischemic; Coronary Vessels; Drug-Eluting Stents; Everolimus; Female; Fibrin; Heart Failure; Humans; Inflammation; Japan; Male; Middle Aged; Neointima; Pancreatitis; Pneumonia; Renal Insufficiency; Risk Factors; Sepsis; Sirolimus; Treatment Outcome | 2018 |
Inhibition of autophagy with 3-methyladenine is protective in a lethal model of murine endotoxemia and polymicrobial sepsis.
Here, the regulatory role of autophagy is examined in both an LPS-induced lethal endotoxic shock mouse model and cecal ligation and puncture (CLP) mouse model. Autophagy-inhibitor 3-methyladenine (3-MA) and autophagy-enhancer rapamycin were administrated to mice challenged with LPS or CLP. Animals challenged with LPS or CLP combined with 3-MA displayed increased survival after endotoxemia, but LPS combined with rapamycin worsened the endotoxic shock of the mice. Among the different organs studied, the lungs and intestines exhibited significant differences among LPS alone, LPS combined with 3-MA and LPS combined with rapamycin. LPS combined with 3-MA attenuated the inflammatory damages of these organs as compared with LPS alone. In contrast, LPS combined with rapamycin increased damage in these organs. Consistently, serum inflammatory mediators TNF-α and IL-6 were decreased by the treatment of LPS combined with 3-MA as compared with LPS alone, while administration of LPS combined with rapamycin increased the serum TNF-α and IL-6 levels. Similar results were found in mouse bone marrow-derived macrophages exposed to LPS. Moreover, the regulatory effect of autophagy to endotoxic shock is dependent on the TLR4 signaling pathway. Our results demonstrate the central role of autophagy in the regulation of endotoxic shock and its potential modulation for endotoxic shock treatment. Topics: Adenine; Animals; Autophagy; Carrier Proteins; Endotoxemia; Interleukin-6; Lipopolysaccharides; Male; Mice; Mice, Inbred C57BL; Microtubule-Associated Proteins; Sepsis; Shock, Septic; Signal Transduction; Sirolimus; Tumor Necrosis Factor-alpha | 2018 |
Differential risks for adverse outcomes 3 years after kidney transplantation based on initial immunosuppression regimen: a national study.
We examined integrated national transplant registry, pharmacy fill, and medical claims data for Medicare-insured kidney transplant recipients in 2000-2011 (n = 45 164) from the United States Renal Data System to assess the efficacy and safety endpoints associated with seven early (first 90 days) immunosuppression (ISx) regimens. Risks of clinical complications over 3 years according to IS regimens were assessed with multivariate regression analysis, including the adjustment for covariates and propensity for receipt of a nonreference ISx regimen. Compared with the reference ISx (thymoglobulin induction with tacrolimus, mycophenolate, and prednisone maintenance), sirolimus-based ISx was associated with significantly higher three-year risks of pneumonia (adjusted hazard ratio, aHR 1.45; P < 0.0001), sepsis (aHR 1.40; P < 0.0001), diabetes (aHR 1.21; P < 0.0001), acute rejection (AR; adjusted odds ratio, aOR 1.33; P < 0.0001), graft failure (aHR 1.78; P < 0.0001), and patient death (aHR 1.40; P < 0.0001), but reduced skin cancer risk (aHR 0.71; P < 0.001). Cyclosporine-based IS was associated with increased risks of pneumonia (aHR 1.17; P < 0.001), sepsis (aHR 1.16; P < 0.001), AR (aOR 1.43; P < 0.001), and graft failure (aHR 1.39; P < 0.001), but less diabetes (aHR 0.83; P < 0.001). Steroid-free ISx was associated with the reduced risk of pneumonia (aHR 0.89; P = 0.002), sepsis (aHR 0.80; P < 0.001), and diabetes (aHR 0.77; P < 0.001), but higher graft failure (aHR 1.35; P < 0.001). Impacts of ISx over time warrant further study to better guide ISx tailoring to balance the efficacy and morbidity. Topics: Adolescent; Adult; Cyclosporine; Diabetes Mellitus; Female; Humans; Immunosuppression Therapy; Immunosuppressive Agents; Kidney Transplantation; Male; Middle Aged; Multivariate Analysis; Mycophenolic Acid; Pneumonia; Renal Insufficiency; Risk; Sepsis; Sirolimus; Tacrolimus; United States; Young Adult | 2016 |
Inhibition of mTORC1 renders cardiac protection against lipopolysaccharide.
Sepsis-induced cardiac dysfunction is a severe clinical problem. It is evident that rapamycin can protect heart from pathological injuries. However, there are no data demonstrating rapamycin reverse cardiac dysfunction induced by sepsis. In this study, Lipopolysaccharide (LPS) was administrated to mice and H9c2 cells. After treatment, we further determined cardiac function by echocardiography, ANP, BNP and inflammatory markers by qPCR and apoptosis by TUNEL staining. Moreover, mTORC1 signaling pathway and Akt activity were measured by Western blots. We found that rapamycin attenuated cardiac dysfunction, increase in ANP and BNP as well as apoptosis induced by LPS both in mice and in H9c2 cells. Unexpectedly, LPS did not significantly affect the mRNA levels of TNF-α and IL-6. Furthermore, rapamycin further reduced the decrease in mTORC1 signaling and Akt activity induced by LPS. In conclusion, rapamycin can protect heart from LPS induced damages by inhibition mTORC1 signaling and elevation of Akt activity. Topics: Animals; Apoptosis; Blotting, Western; Cell Line; Disease Models, Animal; Echocardiography; Heart; Immunosuppressive Agents; In Situ Nick-End Labeling; Lipopolysaccharides; Mechanistic Target of Rapamycin Complex 1; Mice; Mice, Inbred C57BL; Multiprotein Complexes; Proto-Oncogene Proteins c-akt; Rats; Real-Time Polymerase Chain Reaction; Sepsis; Sirolimus; TOR Serine-Threonine Kinases | 2014 |
Enhancing autophagy with activated protein C and rapamycin protects against sepsis-induced acute lung injury.
Autophagy plays distinct roles in apoptosis and the inflammatory process. Understanding the role of autophagy in sepsis-induced acute lung injury (ALI) may provide new insights into developing novel therapeutic strategies for this group of patients. The aim of this study was to investigate the regulation of autophagy in the septic lung and to use pharmacologic agents to modulate autophagy to study its functional significance.. Mice were subjected to cecal ligation and puncture (CLP) or a sham operation. At 1 hour after CLP, mice were treated with vehicle, activated protein C (APC), rapamycin, or bafilomycin A1. Mice were humanely killed at 4 or 24 hours after the operation or were observed for ≤ 7 days.. CLP induced a systemic inflammatory response and significantly decreased survival. In lung tissue, increased leukocyte infiltration, inflammation, and apoptosis were observed. In contrast, autophagy was suppressed after CLP such that the expression of LC3II, Atg5, and Rab7 were downregulated. Rapamycin activated autophagy, limited the CLP-induced proinflammatory response, and downregulated apoptotic activity after CLP. The administration of APC after CLP had an effect similar to that of rapamycin. Both medications significantly improved survival 7 days after CLP.. The downregulation of autophagy may lead to systemic inflammation and ALI after sepsis. The direct or indirect modification of autophagy using rapamycin or APC, respectively, resulted in improved survival. Enhancing or restoring autophagy early after sepsis seems to be a potential strategy for the treatment of sepsis-induced ALI. Topics: Acute Lung Injury; Animals; Anti-Bacterial Agents; Apoptosis; Autophagy; Biomarkers; Blotting, Western; Cecum; Cells, Cultured; Cytokines; Humans; Immunohistochemistry; Ligation; Macrolides; Male; Mice; Mice, Inbred C3H; Protein C; Sepsis; Sirolimus | 2013 |
Complete induction of autophagy is essential for cardioprotection in sepsis.
To investigate the entire process of autophagy in the left ventricle of septic mice, and the functional significance of autophagy by using pharmacological agents.. Myocardial dysfunction is a common feature in sepsis and contributes to an increased risk of developing multiple organ failure. Autophagy functions predominantly as a prosurvival pathway in the heart during cellular stress. A dynamic process of autophagy that involves the complete activation of autophagy from autophagosome formation to fusion with lysosomes has driven the development of new approaches to detecting autophagy.. Male mice were subjected to cecal ligation and puncture (CLP) or sham operation. At 1 hour after CLP operation, mice received either rapamycin (induction of autophagy), bafilomycin A1 (inhibition of autophagosomal degradation), or vehicle.. The formation of autophagosomes was increased whereas the degradation of autophagosomes was decreased in the left ventricle at 24 hours after CLP. This was consistent with the morphologic finding that septic hearts revealed an increase in autophagosomes but few autolysosomes, indicating incompletion of the autophagic process. Rapamycin, which induced complete activation of autophagy, restored CLP-induced depressed cardiac performances. This cardioprotective effect was also seen in increased ATP levels, and decreased inflammatory responses. Bafiomycin A1, which resulted in incompletion of the autophagic process, did not show any above beneficial effects in CLP mice.. Incompletion of the autophagic process may contribute to sepsis-induced cardiac dysfunction. Treatment with rapamycin may serve a cardioprotective role in sepsis, possibly through the effect of complete induction of autophagy. Topics: Animals; Autophagy; Disease Models, Animal; Heart Ventricles; Immunosuppressive Agents; Male; Mice; Mice, Inbred C3H; Sepsis; Sirolimus; Ventricular Dysfunction, Left | 2011 |
[Role of Janus kinase/signal transducer and activator of transcription pathway in mediating mRNA expression of high mobility group box1 protein in the liver in septic rats].
To investigate the role of Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway in mediating mRNA expression of high mobility group box 1 protein (HMGB1) in the liver in septic rats.. Using a sepsis model of cecal ligation and puncture (CLP), 98 male Wistar rats were randomly divided into normal control group (n=10), CLP group (n=40), AG490 treatment group (n=24), and Rapamycin (RPM) treatment group (n=24). At serial time points animals in each group were sacrificed, and blood as well as hepatic tissue samples were harvested to determine HMGB1 mRNA expression and serum aspartate aminotransferase (AST) as well as alanine aminotransferase (ALT) contents.. Compared with normal controls, HMGB1 mRNA levels were significantly increased in the liver during 6-48 hours after CLP (P<0.01), and serum AST and ALT contents were significantly elevated at different time points respectively (P<0.05 or P<0.01). Treatment with AG490 and RPM could markedly inhibit HMGB1 mRNA expression in the liver at 24 hours, 48 hours, 6 hours and 24 hours after CLP, respectively. In addition, compared to CLP group, serum AST and ALT contents in both treatment groups could be markedly reduced at various intervals after CLP (P<0.05 or P<0.01).. These data suggest that the activation of JAK/STAT pathway might be involved in mediating up-regulation of HMGB1 mRNA expression in the liver in CLP-induced sepsis. Treatment with inhibitors of JAK/STAT pathway could markedly down-regulate HMGB1 mRNA expression and attenuate acute liver injury associated with sepsis. Topics: Alanine Transaminase; Animals; Anti-Bacterial Agents; Aspartic Acid; Disease Models, Animal; DNA-Binding Proteins; Enzyme Inhibitors; Gene Expression; HMGB1 Protein; Liver; Male; Protein-Tyrosine Kinases; Random Allocation; Rats; Rats, Wistar; RNA, Messenger; Sepsis; Signal Transduction; Sirolimus; Trans-Activators; Transcription, Genetic; Transcriptional Activation; Tyrphostins | 2003 |