sirolimus and Multiple-Organ-Failure

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

Increasing evidence implicates mitochondrial dysfunction as an early, important event in the pathogenesis of critical illness-induced multiple organ failure. We previously demonstrated that prevention of hyperglycemia limits damage to mitochondria in vital organs, thereby reducing morbidity and mortality. We now hypothesize that inadequate activation of mitochondrial repair processes (clearance of damaged mitochondria by autophagy, mitochondrial fusion/fission, and biogenesis) may contribute to accumulation of mitochondrial damage, persistence of organ failure, and adverse outcome of critical illness.. Prospective, randomized studies in a critically ill rabbit model.. University laboratory.. Three-month-old male rabbits.. We studied whether vital organ mitochondrial repair pathways are differentially affected in surviving and nonsurviving hyperglycemic critically ill animals in relation to mitochondrial and organ damage. Next, we investigated the impact of preventing hyperglycemia over time and of administering rapamycin as an autophagy activator.. In both liver and kidney of hyperglycemic critically ill rabbits, we observed signs of insufficient autophagy, including accumulation of p62 and a concomitant decrease in the microtubule-associated protein light-chain-3-II/microtubule-associated protein light-chain-3-I ratio. The phenotype of insufficient autophagy was more pronounced in nonsurviving than in surviving animals. Molecular markers of insufficient autophagy correlated with impaired mitochondrial function and more severe organ damage. In contrast, key players in mitochondrial fusion/fission or biogenesis were not significantly different regarding survival status. Therefore, we focused on autophagy to study the impact of preventing hyperglycemia. Both after 3 and 7 days of illness, autophagy was better preserved in normoglycemic than in hyperglycemic rabbits, which correlated with improved mitochondrial function and less organ damage. Stimulation of autophagy in kidney with rapamycin correlated with protection of renal function.. Our findings put forward insufficient autophagy as a potentially important contributor to mitochondrial and organ damage in critical illness and open perspectives for therapies that activate autophagy during critical illness.

Topics: Animals; Autophagy; Biomarkers; Critical Illness; Hyperglycemia; Immunosuppressive Agents; Kidney; Male; Microtubule-Associated Proteins; Mitochondria, Liver; Mitochondrial Diseases; Mitochondrial Dynamics; Mitophagy; Multiple Organ Failure; Prospective Studies; Rabbits; Random Allocation; Sirolimus; Survival Analysis

Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway plays an important role in sepsis, transducing a multitude of inflammatory signals. To date, knowledge of JAK/STAT pathway in sepsis is limited. This study was to investigate the potential role of JAK/STAT pathway in mediating multiple organ damage and mortality in septic rats. Our data showed that inhibition of JAK2/STAT3 attenuated cecal ligation and puncture-induced multiple organ damage and mortality in 48 hours in rats.. A total of 98 male Wistar rats were randomly divided into 4 groups as follows: (1) normal control group (n = 10); (2) cecal ligation and puncture (CLP) group (n = 40), which was further divided into 2, 6, 24, 48-hour post-CLP groups; (3) AG490 (8.0 mg/kg, Calbiochem, La Jolla, CA) treatment group (n = 24), which was further divided into 2, 6, 24, 48-hour post-CLP groups; (4) rapamycin (0.4 mg/kg, Calbiochem, Calbiochem, La Jolla, CA) treatment group (n = 24), which was further divided into 2, 6, 24, 48-hour post-CLP groups; CLP was performed to induce experimental sepsis. AG490 (8 mg/kg) or rapamycin (0.4 mg/kg) was injected subcutaneously 0.5 hour before CLP in respective group. Animals were killed at destined time after CLP (not including the death rate observation group), and specimens of serum, liver, and lungs were harvested and stored in liquid nitrogen for subsequent analyses. In an additional experiment, 88 animals were randomly divided into three groups to compare the survival rate, including CLP group (n = 40), AG490 treatment group (8 mg/kg, n = 24), and rapamycin treatment group (0.4 mg/kg, n = 24). Mortality of rats in each group was recorded up to 48 hours after the procedure.. After CLP challenge, myeloperoxidase (MPO), aspartate transaminase, and alanine aminotransferase levels, as well as activation of JAK2 and STAT3, were markedly increased. Administration of AG490 or rapamycin significantly decreased activation of JAK2 and STAT3, as well as high mobility group box-1 protein, MPO, alanine aminotransferase levels (p < 0.05 or p < 0.01). In addition, treatment with AG490 or rapamycin significantly improved the 48-hour survival rate from 37.5% (15 of 40) to 66.7% (16 of 24) and 70.8% (17 of 24), respectively (both p < 0.05).. JAK2/STAT3 pathway might play a role in the development of multiple organ damage in septic rats, which suggested a potential strategy to control sepsis.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Cecum; Drug Administration Schedule; Enzyme Inhibitors; HMGB1 Protein; Janus Kinase 2; Male; Multiple Organ Failure; Peroxidase; Rats; Rats, Wistar; Signal Transduction; Sirolimus; STAT3 Transcription Factor; Survival Rate; Tyrphostins

Topics: Acute Coronary Syndrome; Angioplasty, Balloon, Coronary; Cardiovascular Agents; Coronary Angiography; Coronary Artery Disease; Drug-Eluting Stents; Fatal Outcome; Humans; Male; Multiple Organ Failure; Platelet Aggregation Inhibitors; Sirolimus; Thrombosis; Time Factors; Tomography, X-Ray Computed; Treatment Outcome; Ultrasonography, Interventional