Organ Dysfunction In Rats Research Articles

Longevity Spinach (Gynura procumbens) Ameliorated Oxidative Stress and Inflammatory Mediators in Cisplatin-Induced Organ Dysfunction in Rats: Comprehensive in vivo and in silico Studies.

This study focused to assess the efficacy of Gynura procumbens (GP) leaf extract against cisplatin (CP)-induced hepatorenal complications in Wister albino rats. Additionally, it aims to detect polyphenolic compounds using high-performance liquid chromatography with diode-array detection (HPLC-DAD). The rats were treated intraperitoneally with CP (7.5 mg/kg) to mediate hepatorenal damage. They were then treated with GP extract (75 and 150 mg/kg, P.O.) for 7 consecutive days. Although GP extract significantly ameliorated CP-mediated hepatorenal biomarkers like alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine, and blood urea nitrogen (BUN) levels in a dose-dependent manner, GP extract at 150 mg/kg dose normalized hepatorenal biomarkers ALP (45.11 U/L), ALT (34 U/L), AST (29 U/L), creatinine (10.3 mg/dl) and BUN (11.19 mg/dl) while comparing to control and disease group. Similarly, though it significantly reduced CP-induced oxidative stress inducers, including nitric oxide (NO) and advanced oxidative protein products (AOPP), higher dose (150 mg/kg) exhibited better activity in reducing NO (281.54 mmol/gm tissue in liver and 52.73 mmol/gm tissue in the kidney) and AOPP (770.95 mmol/mg protein in liver and 651.90 mmol/mg protein in the kidney). Besides, it showed better enhancement in the antioxidant enzymes superoxide dismutase, and glutathione levels at a higher dose (150 mg/kg). Histopathological studies showed that CP caused collagen accumulation in the liver and kidney tissues. GP extract drained the collagen mass and acted against hepatorenal damage. Ellagic acid, gallic acid, quercetin hydrate, kaempferol, and rutin hydrate were revealed in GP extract. In-silico modelling showed good docking scores of the polyphenolic compounds with molecular targets including CYP4502E1, NF-κB, caspase-3, and TNF-α. GP could be an effective therapeutic option for management of anticancer drugs' complications like CP-induced organ damage, although clinical studies are required to establish herbal formulation.

Magnesium hydride attenuates intestinal barrier injury during hemorrhage shock by regulating neutrophil extracellular trap formation via the ROS/MAPK/PAD4 pathway

Magnesium hydride (MgH2) is a hydrogen storage material that is known for its high capacity and safety and is capable of releasing hydrogen in a controlled manner when administered orally. This release of hydrogen has been associated with a range of biological effects, including anti-inflammatory properties, antioxidant activity, and protection of the intestinal barrier. Previous research has shown that neutrophil extracellular traps (NETs) play a role in the dysfunction of the intestinal barrier in conditions such as sepsis and critical illnesses. However, it remains unclear as to whether MgH2 can protect the intestinal barrier by inhibiting NET formation, and the underlying mechanisms have yet to be elucidated. A rat model of hemorrhagic shock was created, and pretreatment or posttreatment procedures with MgH2 were performed. After 24 h, samples from the small intestine and blood were collected for analysis. In vitro, human neutrophils were incubated with either phorbol-12-myristate-13-acetate (PMA) or MgH2. Reactive oxygen species generation and the expression of key proteins were assessed. The results demonstrated that MgH2 administration led to a decrease in inflammatory cytokines in the serum and mitigated distant organ dysfunction in rats with HS. Furthermore, MgH2 treatment reversed histopathological damage in the intestines, improved intestinal permeability, and enhanced the expression of tight junction proteins (TJPs) during HS. Additionally, MgH2 treatment was found to suppress NET formation in the intestines. In vitro pretreatment with MgH2 alleviated intestinal monolayer barrier disruption that was induced by NETs. Mechanistically, MgH2 pretreatment reduced ROS production and NET formation, inhibited the activation of ERK and p38, and suppressed the expression of the PAD4 protein. These findings indicated that MgH2 may inhibit NET formation in a ROS/MAPK/PAD4-dependent manner, which reduces NET-related intestinal barrier damage, thus offering a novel protective role in preventing intestinal barrier dysfunction during HS.

Inhibition of Macrophage Migration Inhibitory Factor Activity Attenuates Haemorrhagic Shock-Induced Multiple Organ Dysfunction in Rats.

ObjectiveThe aim of this study was to investigate (a) macrophage migration inhibitory factor (MIF) levels in polytrauma patients and rats after haemorrhagic shock (HS), (b) the potential of the MIF inhibitor ISO-1 to reduce multiple organ dysfunction syndrome (MODS) in acute (short-term and long-term follow-up) HS rat models and (c) whether treatment with ISO-1 attenuates NF-κB and NLRP3 activation in HS.BackgroundThe MODS caused by an excessive systemic inflammatory response following trauma is associated with a high morbidity and mortality. MIF is a pleiotropic cytokine which can modulate the inflammatory response, however, its role in trauma is unknown.MethodsThe MIF levels in plasma of polytrauma patients and serum of rats with HS were measured by ELISA. Acute HS rat models were performed to determine the influence of ISO-1 on MODS. The activation of NF-κB and NLRP3 pathways were analysed by western blot in the kidney and liver.ResultsWe demonstrated that (a) MIF levels are increased in polytrauma patients on arrival to the emergency room and in rats after HS, (b) HS caused organ injury and/or dysfunction and hypotension (post-resuscitation) in rats, while (c) treatment of HS-rats with ISO-1 attenuated the organ injury and dysfunction in acute HS models and (d) reduced the activation of NF-κB and NLRP3 pathways in the kidney and liver.ConclusionOur results point to a role of MIF in the pathophysiology of trauma-induced organ injury and dysfunction and indicate that MIF inhibitors may be used as a potential therapeutic approach for MODS after trauma and/or haemorrhage.

Inhibition of Bruton's Tyrosine Kinase Activity Attenuates Hemorrhagic Shock-Induced Multiple Organ Dysfunction in Rats.

The aim of this study was to investigate (a) the potential of the Bruton's tyrosine kinase (BTK) inhibitors acalabrutinib and fenebrutinib to reduce multiple organ dysfunction syndrome (MODS) in acute (short-term and long-term follow-up) hemorrhagic shock (HS) rat models and (b) whether treatment with either acalabrutinib or fenebrutinib attenuates BTK, NF-κB and NLRP3 activation in HS. The MODS caused by an excessive systemic inflammatory response following trauma is associated with a high morbidity and mortality. The protein BTK is known to play a role in the activation of the NLRP3 inflammasome, which is a key component of the innate inflammatory response. However, its role in trauma-hemorrhage is unknown. Acute HS rat models were performed to determine the influence of acalabrutinib or fenebrutinib on MODS. The activation of BTK, NF-κB and NLRP3 pathways were analyzed by western blot in the kidney. We demonstrated that (a) HS caused organ injury and/or dysfunction and hypotension (post-resuscitation) in rats, while (b) treatment of HS-rats with either acalabrutinib or fenebrutinib attenuated the organ injury and dysfunction in acute HS models and (c) reduced the activation of BTK, NF- kB and NLRP3 pathways in the kidney. Our results point to a role of BTK in the pathophysiology of organ injury and dysfunction caused by trauma/hemorrhage and indicate that BTK inhibitors may be repurposed as a potential therapeutic approach for MODS after trauma and/or hemorrhage.

The effect of adenosine A2A receptor antagonist istradefylline on multiple organ dysfunction in heatstroke rats

Background: Global warming increases the incidence of heatstroke, which is the most severe heat illness. The mortality in patients with heatstroke is due to neurological disability and multiple organ failure caused by systemic inflammatory response. Adenosine A2A receptor antagonist has both neuroprotective and anti-inflammatory effects. Thus, we examined whether a new A2A receptor antagonist istradefylline has beneficial effects in heatstroke rats. Methods: Wistar rats were divided into four groups: (1) control group, with vehicle only (intravenous [iv] for 10 min); (2) control + istradefylline group, with 0.3 mg/kg istradefylline (iv for 10 min); (3) heatstroke group, rectal temperature reached 44.1°C, and then returned to room temperature with vehicle (iv for 10 min); and (4) heatstroke + istradefylline group, rectal temperature reached 44.1°C, and then returned to room temperature with 0.3 mg/kg istradefylline (iv for 10 min). During the experimental period, rectal temperature, heart rate, blood pressure, and pressor responses to norepinephrine (NE) were monitored. Before and after the rats were put into heating chamber, and after the rats returned to room temperature for 6 h, their blood was taken to analyze creatine kinase, lactate dehydrogenase, blood urea nitrogen, creatinine, alanine transaminase, albumin, total protein, and platelet count. In addition, the blood flow of tongue, left limb, and right limb was also monitored. Finally, we examined their survival rate. Results: In the present study, heatstroke rats showed high core body temperature accompanied with cardiac abnormalities and multiple organ dysfunction, mimicking the clinical manifestations of heatstroke patients. Treatment of heatstroke rats with istradefylline only partially improved platelet loss and vascular hyporeactivity to NE. However, istradefylline had no significant effects on cardiac abnormalities and multiple organ dysfunction in rats with heatstroke. Conclusions: These results suggest that although istradefylline has a mild impact on abnormal platelet count and pressor response to NE in heatstroke, both effects are unlikely to counteract multiple organ dysfunction and the mortality.

Effects of different core temperatures after heat strike on serum inflammatory cytokines and multiple organ dysfunction syndrome in rats

To observe the effect of different core temperatures (Tc) after heat strike on serum inflammatory cytokines and multiple organ dysfunction syndrome (MODS) in rat. 120 male Sprague-Dawley (SD) rats were randomly divided into normal control group (n = 30) and heat strike group (n = 90). The rats in heat strike group were put into simulated thermal climate animal module after adaptive training. The module temperature was raised to 39 centigrade in 30 minutes with 65% humidity. The rats ran simultaneously at 15 m/min, on the slope of 0 degree angle, 8 minutes each time, 2 minutes interval, and the heat strike time was 90 minutes. After the rats came out of the module, rectal temperature, which was Tc value, was recorded. The rats died or Tc < 41 centigrade during the experiment were excluded, the remaining 73 rats were divided into three subgroups: 41.0-41.9 centigrade (n = 38), 42.0-42.9 centigrade (n = 26), and ≥43.0 centigrade (n = 9). The rats in the normal control group were reared at temperature of (25±2) centigrade, and humidity of (55±5)%. At 0 hour and 24 hours after the rats came out of the module, femoral artery blood was collected to determine serum interleukins (IL-1α, IL-1β, IL-17), tumor necrosis factor-α(TNF-α) andγ-interferon (IFN-γ) by enzyme-linked immunosorbent assay (ELISA). The cardiac troponin I (cTnI), MB isoenzyme of creatine kinase (CK-MB), serum creatinine (SCr), blood urea nitrogen (BUN), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) levels were determined by automatic biochemical analyzer. The incidence of MODS and the number of accumulative organs within 24 hours of the rats in different Tc of heat strike group were compared and analyzed. The serum inflammatory cytokines and biochemical parameters at 0 hour after heat strike were significant higher than those of the normal control group, and showed a time dependence. Further analysis showed that the inflammatory response and organ dysfunction in rats were increased gradually with the increase in Tc of rats. Compared with the normal control group, at 24 hours after heat strike, inflammatory cytokines in Tc≥43.0 centigrade rats were increased obviously [IL-1α (ng/L): 13.56±2.07 vs. 2.24±0.62, IL-1β (ng/L): 17.11±1.90 vs. 7.40±1.52, IL-17 (ng/L): 17.00±1.41 vs. 6.00±1.78, TNF-α (ng/L): 16.78±1.79 vs. 7.27±1.74, IFN-γ (ng/L): 21.11±2.09 vs. 10.43±2.31], and the biochemical parameters were also increased obviously [cTnI (ng/L): 50.78±6.67 vs. 20.53±3.09, CK-MB (U/L): 62.89±3.82 vs. 22.00±3.01, SCr (μmol/L): 149.22±4.35 vs. 92.53±8.32, BUN (nmol/L): 55.22±1.99 vs. 19.10±2.02, ALT (U/L): 388.33±4.97 vs. 100.23±10.61, AST (U/L): 361.22±6.53 vs. 97.67±10.54, all P < 0.01]. The incidence of MODS within 24 hours in the heat strike group was 54.79% (40/73), and the higher the Tc, the higher the incidence of MODS, and the more insulted organs [the incidence of MODS in 41.0-41.9 centigrade, 42.0-42.9 centigrade, and ≥43.0 centigrade subgroups was 36.84% (14/38), 65.38% (17/26), 100.00% (9/9), and the organ involvement rate was 12.17% (37/304), 23.08% (48/208), and 48.61% (35/72), respectively, when 8 organs or systems were calculated for each rat, both P < 0.01]. The higher the Tc of heat strike rats, the stronger the inflammatory reaction and the more serious the damage of tissue, and the more extensive damage of the organs.

Levosimendan mitigates coagulopathy and organ dysfunction in rats with endotoxemia

BackgroundIn patients with severe sepsis, pro-inflammatory cytokines and subsequent activation of tissue factors trigger a cascade of events that lead to coagulation dysfunction and multiple organ failure. It has been shown that levosimendan has protective effects against tissue injury caused by endotoxin. The purpose of this study was to evaluate the effects of levosimendan on consumptive coagulopathy and organ dysfunction in an endotoxemic animal model induced by lipopolysaccharide (LPS). MethodsForty-six male adult Wistar rats were randomly divided into four groups: 1) control group (n = 10), an intravenous infusion of 5% dextrose 1.2 mL/kg for 20 min and 0.03 mL/kg/min for 4 h; 2) the levosimendan-treated control group (n = 12), an intravenous levosimendan infusion (24 μg/kg for 20 min plus 0.6 μg/kg/min for 4 h); 3) the LPS group (n = 12), an intravenous LPS (4 mg/kg) infusion followed by dextrose administration; and 4) the levosimendan-treated LPS group (n = 12), an intravenous LPS infusion followed by levosimendan treatment. Various parameters of hemodynamics, biochemistry, hemostasis and inflammatory response were examined during the experimental period. ResultsThe administration of levosimendan significantly attenuated (i) consumptive coagulopathy displayed by thromboelastography, (ii) the decreases of platelet count and plasma fibrinogen level, (iii) injury in the lung, liver and kidney, and (iv) the rise in plasma interleukin-6 in rats treated with LPS. ConclusionThe treatment of LPS rats with levosimendan was found to reduce organ injury and coagulopathy. These protective effects may be attributed to the anti-inflammatory effects of this drug.

Intraintestinal administration of ulinastatin protects against sepsis by relieving intestinal damage

BackgroundIntravenous administration of ulinastatin (UTI), a broad spectral protease inhibitor, has been used on an experimental basis with severe sepsis patients in Asia. However, the effects of intraintestinal administration of UTI on intestinal and multiple organ damage in sepsis have not been reported. Materials and methodsIn this study, we established a sepsis model in rats using cecal ligation and puncture and compared the effects of intraintestinal administration of UTI through an artificial fistula of duodenum and intraperitoneal administration of UTI on the pathophysiological changes of sepsis. ResultsIt was found that intraintestinal administration of UTI (1) significantly improved the survival of septic rats, (2) significantly reduced the serum levels of tumor necrosis factor-α, interleukin-1β, interleukin-6 as well as intestinal injury biomarkers diamine oxidase, D-lactic acid, and fluorescein isothiocyanate-dextran 4, and (3) significantly reduced intestinal microscopic and ultrastructural damage of septic rats. In addition, the protective effects of intraintestinal administration of UTI were significantly better than those of intraperitoneal administration of UTI. ConclusionsOverall, the present study for the first time revealed that intraintestinal administration of protease inhibitor UTI could reduce systemic inflammatory responses and multiple organ dysfunction in rats with sepsis by inhibiting autodigestion of intestinal wall due to proteases and provided new research ideas and experimental evidences for treatment of sepsis by intraintestinal administration of UTI.

Procainamide Inhibits DNA Methylation and Alleviates Multiple Organ Dysfunction in Rats with Endotoxic Shock

Excessive inflammatory and oxidative stress lead to circulatory failure, multiple organ dysfunction, and high mortality in patients with sepsis. Microbial infection-induced DNA hypermethylation is associated with the augmentation of inflammation and oxidative stress. In our previous study, the antiarrhythmic drug procainamide inhibits the expression of DNA methyltransferase 1 (DNMT1) and diminishes IL-6 levels in rats with rhabdomyolysis. Thus, we further evaluated the effects of procainamide on the development of circulatory failure and multiple organ dysfunction in rats with endotoxic shock. Male Wistar rats were intravenously infused with saline or lipopolysaccharide (LPS) followed by procainamide administration. The changes of hemodynamics, blood glucose, biochemical variables, and plasma nitric oxide (NO) levels were analyzed during the experimental period. At the end of experiments, animal organs were also obtained for examining superoxide production, neutrophil infiltration, and DNA methylation status. Our results showed that LPS induced circulatory failure, multiple organ dysfunction, and high mortality rate in endotoxemic rats. Overt neutrophil infiltration and superoxide production, accompanied by the elevations of DNMT1 and 5-methylcytosine levels in the lung of endotoxemic rats were also observed. Treatment of endotoxemic animals with procainamide not only inhibited the increased levels of DNMT1 and 5-methylcytosine but also ameliorated neutrophil infiltration and superoxide production in the lung. In addition, the anti-inflammatory gene, IL27RA, was down-regulated in the LPS group and up-regulated in the LPS + Procainamide group. Procainamide also diminished IL27RA methylation in the lung of endotoxemic rat. Moreover, both DNMT inhibitors procainamide and hydralazine improved hypotension, hypoglycemia, and multiple organ dysfunction of LPS-treated rats. Thus, we suggest that the beneficial effects of procainamide could be attributed to the suppression of DNA methylation, neutrophil infiltration, superoxide production, and NO formation. It seems that this old drug may have new potential uses in infectious diseases, in particular, associated with endotoxemia.

Effects of gabexate mesilate on coagulopathy and organ dysfunction in rats with endotoxemia

Sepsis and its associated multiple organ failure are related to high mortality in critical patients. Several studies have reported that gabexate mesilate, a synthetic inhibitor of trypsin-like serine protease, protects tissues/organs against injury in the models of endotoxemia. The aim of this study was to examine whether gabexate mesilate could attenuate coagulopathy and organ dysfunction in lipopolysaccharide (LPS)-induced sepsis model by using thrombelastography (TEG). LPS (7.5 mg/kg/h, intravenouly for 4 h) was administered to male adult Wistar rats. Some of the LPS rats received a continuous infusion of gabexate mesilate (10 mg/kg/h, intravenously for 8.5 h) for 30 min before the LPS administration. Variable parameters of hemodynamics, biochemistry, hemostasis and inflammatory response were measured for 6 h after the LPS infusion. TEG variables (R-time, K-time, α-angle, and maximal amplitude) were also measured. The pretreatment of LPS rats with gabexate mesilate significantly attenuated the lung, liver and kidney dysfunction, consumptive coagulopathy, the increases in serum tumor necrosis factor-α, interleukin-6, plasma thrombin-antithrombin complex and plasminogen activator inhibitor-1, and neutrophils infiltration score in lung, liver and kidney, compared with the LPS alone group. In addition, TEG parameters correlated with tissue and liver injury in the late phase of endotoxemia. In particular, a strong negative correlation between maximal amplitude at 4 h and Ln (lactate dehydrogenase) at 6 h after LPS infusion was noted (r = -0.752, P < 0.001, R = 0.566). These results indicate that beneficial effects of anticoagulants (e.g. gabexate mesilate) in endotoxemia could be monitored by TEG per se.

Sepsis progression and multiple organ dysfunction in rats: carotid body involvement (873.5)

Sepsis syndromes involve pathological processes often leading to multiple organ dysfunction (MOD) and death. Sepsis progresses to MOD due uncontrolled release of inflammatory mediators. Lately, increasing evidence supports the idea that the carotid body both regulates the immune status and plays a protective role during sepsis syndromes. In anaesthetized (pentobarbitone, 60 mg/kg IP) male Sprague‐Dawley rats (BW 100±20 g) we measured plasma levels of cytokines, chemokines and MOD‐markers, 90‐min after IP administration of either saline or 15 mg/kg LPS in control (SHAM surgery; intact carotid/sinus nerves) and in bilateral carotid chemo/baro‐denervated rats (BCN). Respiratory frequency (fR) and heart rate (fH) were augmented in SHAM‐LPS group, but systolic blood pressure (PS) dropped. BCN decreases the survival time of rats and blunts the fR response to LPS but enhancing both, the fH increase and the PS fall. SHAM‐LPS and BCN‐LPS rats shown increased plasma levels of IL‐1β, IL‐10, and TNF‐α; however, the increase in both ILs was lower in BCN‐LPS, which also had augmented IL‐2 levels. Unchanged cortisol plus increased levels of epinephrine can be related to increased plasma levels of TNF‐α. Finally, BCN‐LPS induced an early onset of MOD identified by increased plasma levels of creatine kinase, amylase, creatinine, neutrophil gelatinase‐associated lipocaline, total bilirrubin and alanine aminotransferase. We propose that carotid body would modify the inflammatory response during sepsis syndromes through a communication network involving neural, humoral, and cytokine components, and also would play a protective role in the sepsis progression to MOD.Grant Funding Source: Supported by: FONDECYT 1120976 and UNAB DI‐354‐13/R (to RF) and UDD CI 23400098 (to PR)

2-(2-Fluorobenzamido)benzoate ethyl ester (EFB-1) inhibits superoxide production by human neutrophils and attenuates hemorrhagic shock-induced organ dysfunction in rats

Neutrophil activation after trauma–hemorrhagic shock (T/H) has been implicated in the development of multiple organ dysfunction (MOD). In this study, we report that a small chemical compound, 2-(2-fluorobenzamido)benzoic acid ethyl ester (EFB-1), exhibited a potent inhibitory effect on the formyl-l-methionyl-l-leucyl-l-phenylalanine (FMLP)-induced superoxide anion (O2•−) release and CD11b expression by human neutrophils. Additionally, administration of EFB-1 in rats subjected to T/H caused a significant improvement in MOD. EFB-1 treatment induced an increase in cAMP formation and protein kinase (PK) A activity in FMLP-activated neutrophils, which occurred through the selective inhibition of cAMP-specific phosphodiesterase (PDE) activity but not an increase in adenylate cyclase function or cGMP-specific PDE activity. FMLP-induced phosphorylation of protein kinase B (AKT), but not calcium mobilization, was reduced by EFB-1. The inhibitory effects of EFB-1 on O2•− production, CD11b expression, and AKT phosphorylation were reversed by PKA inhibitors (H89 and KT5720). Significantly, administration of EFB-1 (1mg/kg body wt) attenuated the myeloperoxidase activity of the intestines, lungs, and liver and reduced the wet/dry weight ratio of the intestines and lungs and plasma alanine aminotransferase and aspartate aminotransferase levels in Sprague–Dawley rats after T/H. Therefore, EFB-1 is a new inhibitor of cAMP-specific PDE that potently suppresses O2•− release and CD11b expression by human neutrophils and attenuates T/H-induced MOD in rats.

Ulinastatin-mediated protection against zymosan-induced multiple organ dysfunction in rats

The purpose of this study was to evaluate the potential organ-protective activity of ulinastatin (a urinary trypsin inhibitor) and to investigate the underlying mechanism(s) in a rat model of multiple organ dysfunction syndrome (MODS). When adult Wistar rats were challenged intraperitoneally with yeast polysaccharide (zymosan), they developed biochemical and histological abnormalities similar to those seen in human MODS as compared with the controls. Among these abnormalities were: 1) significant increases in serum concentrations of tumor necrosis factor-alpha (TNF-α) and soluble intercellular adhesion molecule-1 (sICAM-1); 2) aberrant values in the liver and kidney function tests; and 3) presence of evident pathology in the major organs (i.e. liver, kidney and lung). In addition, zymosan challenge resulted in an increase in toll-like receptor-4 (TLR4) mRNA abundance in all three organs tested. Ulinastatin treatment significantly decreased the zymosan-induced elevation in serum concentrations of TNF-α and sICAM-1 and tissue abundance of TLR mRNA in the liver, kidney and lung, effectively attenuated the development of the polysaccharide-induced biochemical and histological abnormalities and successfully reduced the MODS-associated death. In conclusion, ulinastatin is able to protect multiple organs from yeast polysaccharide-induced damage and function failure, at least partially, through a TLR4-dependent mechanism, suggesting a therapeutic potential against MODS.

RECOMBINANT FACTOR XIII DIMINISHES MULTIPLE ORGAN DYSFUNCTION IN RATS CAUSED BY GUT ISCHEMIA-REPERFUSION INJURY

Plasma factor XIII (FXIII) is responsible for stabilization of fibrin clot at the final stage of blood coagulation. Because FXIII has also been shown to modulate inflammation and endothelial permeability, we hypothesized that FXIII diminishes multiple organ dysfunction caused by gut I/R injury. A model of superior mesenteric artery occlusion (SMAO) was used to induce gut I/R injury. Rats were subjected to 45-min SMAO or sham SMAO and treated with recombinant human FXIII A2 subunit (rFXIII) or placebo at the beginning of the reperfusion period. Lung permeability, lung and gut myeloperoxidase activity, gut histology, neutrophil respiratory burst, and microvascular blood flow in the liver and muscles were measured after a 3-h reperfusion period. The effect of activated rFXIII on transendothelial resistance of human umbilical vein endothelial cells was tested in vitro. Superior mesenteric artery occlusion-induced lung permeability as well as lung and gut myeloperoxidase activity was significantly lower in rFXIII-treated versus untreated animals. Similarly, rFXIII-treated rats had lower neutrophil respiratory burst activity and ileal mucosal injury. Rats treated with rFXIII also had higher liver microvascular blood flow compared with the placebo group. Superior mesenteric artery occlusion did not cause FXIII consumption during the study period. In vitro, activated rFXIII caused a dose-dependent increase in human umbilical vein endothelial cell monolayer resistance to thrombin-induced injury. Thus, administration of rFXIII diminishes SMAO-induced multiple organ dysfunction in rats, presumably by preservation of endothelial barrier function and the limitation of polymorphonuclear leukocyte activation.

EF6265, a novel inhibitor of activated thrombin-activatable fibrinolysis inhibitor, protects against sepsis-induced organ dysfunction in rats*

Although thrombin-activatable fibrinolysis inhibitor (TAFI) has been implicated as a negative regulator of fibrinolysis, its pathophysiological significance remains to be unveiled. We performed the pharmacologic study to assess the effect of EF6265, a specific inhibitor of activated form of TAFI (TAFIa) on sepsis-induced organ dysfunction models. A controlled, in vivo laboratory study. Company research laboratory. Wistar and Sprague-Dawley rats. Endotoxemia and sepsis models were induced by intravenous injection of lipopolysaccharide and Pseudomonas aeruginosa, respectively. In the endotoxemia model, posttreatment (1 hour) with EF6265 reduced fibrin deposits in the kidney and liver accompanied by no significant changes in platelet count and fibrinogen concentration in plasma. This compound also significantly decreased levels of plasma lactate dehydrogenase and aspartate aminotransferase, markers of organ dysfunction. In the sepsis model, EF6265, simultaneously administered with ceftazidime (CAZ) 2 hours after Pseudomonas aeruginosa injection, showed no influence on the antibiotic activity of CAZ. Meanwhile, it dramatically potentiated the interleukin-6-reducing effect of CAZ in plasma, suggesting that inhibition of TAFIa leads to the reduction in systemic inflammatory response associated with bacterial infection. This combined treatment also lowered plasma lactate dehydrogenase and blood urea nitrogen more potently than single treatment with CAZ. These results clearly suggest that TAFI plays an important role in the deterioration of organ dysfunction in sepsis and the inhibitor of TAFIa protects against sepsis-induced tissue damage through regulation of fibrinolysis and inflammation.

Effects of Midazolam on Organ Dysfunction in Rats with Endotoxemia Induced by Lipopolysaccharide

Sepsis is associated with high mortality and septic patients sometimes need sedation to attenuate anxiety and agitation. Recently, it has been suggested that midazolam, a benzodiazepine, modulates the responses to cytokines released from macrophages in vitro. The purpose of the present study was to evaluate the effect of midazolam on hemodynamics and organic function in rats with septic syndromes induced by intravenous endotoxin. Wistar rats were randomly allocated to three groups and treated intravenously as follows: (1) control group, in which the rats were given saline vehicle (1 mL/kg) at time 0; (2) LPS group, in which the rats were given Escherichia coli lipopolysaccharide (10 mg/kg) in an infusion over 10 minutes; (3) LPS+Midazolam group, in which the rats were given E. coli LPS infusion as in the LPS group followed immediately by infusion of midazolam, given at a rate of 1 microg/kg per hour. All hemodynamic and biochemical parameters were measured during the 4-hour observation period. The injection of LPS led to hypotension, tachycardia, and vascular hyporeactivity to vasoconstrictors. In addition, initial hyperglycemia, delayed hypoglycemia, hypoalbuminemia, elevated serum indicators of hepatic and renal injury and high mortality were also observed in rats treated with LPS. However, midazolam given in the designated dosage did not offer any modulatory effects on hemodynamic responses, multiple organic dysfunction and survival rate in rats with endotoxemia. No deleterious or beneficial effects on hemodynamics and organ dysfunction were observed in the endotoxemic rats treated with midazolam at the designated dosage. However, previous reports which showed substantial benefits from the inhibitory effects of midazolam on proinflammatory factors in vitro should be subjected to further elucidation.

Curcumin attenuates the organ dysfunction caused by endotoxemia in the rat

Objective Curcumin has antioxidant, antitumor, and anti-inflammatory properties. However, it remains unknown whether curcumin has any protective effects on sepsis. The purpose of this study was to demonstrate whether curcumin prevents organ dysfunction in animals with sepsis. Methods Rats were randomized into four groups. The control group (group I, n = 7) did not receive any treatment. The curcumin group (group II, n = 10) only received 1.2 g/kg of curcumin. Escherichia coli were injected into the remaining groups intraperitoneally after general anesthesia. Five hours after injection, 12 rats received placebo (group III), and 10 rats received 1.2 g/kg of curcumin (group IV) for 7 d. All rats were sacrificed on postsepsis day 8 and a midline laparotomy was performed. Livers, kidneys, and small bowels were excised for evaluation of the degree of inflammation and tissue alterations histopathologically. Results In the liver, widespread hydropic degeneration of hepatocytes were seen in the sepsis group. There was no hydropic degeneration of hepatocytes and no portal inflammation in the sepsis/curcumin group. With respect to the small bowel, the sepsis group showed edema and prominent intraepithelial infiltration of neutrophil leucocytes and plasma cells. Inflammation and hyperemia in the lamina propria in the sepsis/curcumin group were less than those in the sepsis group. With respect to the kidneys, the sepsis group showed severe acute tubular necrosis that was more restricted in the sepsis/curcumin group than in the sepsis group. Conclusion Curcumin reduced organ dysfunction in rats with experimentally formed sepsis. We propose that curcumin may be useful in the therapy of organ dysfunction due to sepsis, shock, and other diseases associated with local or systemic inflammation.

Ethyl Pyruvate Improves Survival and Ameliorates Distant Organ Injury in Rats With Severe Acute Pancreatitis

To evaluate the effect of ethyl pyruvate (EP) in improving the survival and ameliorating distant organ damage and to investigate the role of high-mobility group box (HMGB) 1 in rats with established severe acute pancreatitis (SAP). Severe acute pancreatitis was induced by retrograde infusion of sodium taurodeoxycholate (5%, 1 mL/kg) into the biliopancreatic ducts in male Wistar rats. The rats were infused intravenously with EP of 40 mg/kg, 4 mg/kg, and 0.4 mg/kg initiating 12 hours, and EP of 40 mg/kg was administered beginning 2 hours before surgery (-2 hours) and 12, 24, and 36 hours after induction of SAP; then, the mortality was recorded. Serum tumor necrosis factor alpha, interleukin (IL) 6, and IL-1beta were measured using enzyme-linked immunosorbent assay. High-mobility group box 1 levels were measured using Western immunoblotting analysis. Serum HMGB1 levels were increased dramatically after 12 hours, remained at high levels for 72 hours, and were significantly higher in rats with SAP than in those with mild and moderate pancreatitis (P < 0.01). Treatment with EP (40 mg/kg) conferred protection from lethality of SAP (EP survival [63%] vs vehicle survival [6.3%]; P < 0.001). No survival advantage occurred when treatment was initiated 36 hours after surgery, but administration beginning 2 hours before operation (-2 hours) and 12 and 24 hours after induction of SAP significantly increased survival. Ethyl pyruvate treatment significantly decreased serum HMGB1, tumor necrosis factor alpha, IL-1beta, and IL-6 levels and ameliorated extrapancreatic organ dysfunction in rats with SAP. Ethyl pyruvate improves survival and ameliorates distant organ injury of SAP. These beneficial effects of EP are because of the modulation of HMGB1 and other inflammatory cytokine responses.

RELATIONSHIP BETWEEN BIOPTERIN FORMATION AND MULTIPLE ORGAN DYSFUNCTION IN RATS WITH ENDOTOXIC SHOCK

Objective: The current experiment was performed to study the relationship between biopterin formation and multiple organ dysfunction in rats with endotoxic shock. Methods: A rat model of endotoxic shock was reproduced by a bolus injection of lipopolysaccharide (10 mg/kg, i.v.). 104 male Wistar rats were randomly divided into normal controls (n = 8), endotoxic shock group (n = 48), and 2,4-diamino-6-hydroxy-pyrimidine (DAHP) treatment group (n = 48). At serial time points animals in each group were sacrificed, serum samples and tissue specimens from liver, lungs as well as kidneys were harvested. Tissue biopterin contents were measured by reverse-phase HPLC/fluorescence detection. GTP cyclohydrolase I (GTP-CHI) mRNA expression was determined by RT-PCR. Results: Compared to normal controls, tissue biopterin contents in liver, lungs and kidneys were markedly elevated from 0.5 to 2 hrs after endotoxin challenge (P < 0.01), peaking at 6-12 hrs, and gradually decreased afterwards. Concomitantly, GTP-CHI mRNA levels were significantly increased in liver, lungs and kidneys at 0.5 to 2 hrs after endotoxin challenge, and high values were maintained up to 48 hrs. Treatment with DAHP, an inhibitor of tetrahydrobiopterin synthesis, could significantly reduce tissue biopterin contents at 2-24 hrs in rats after lipopolysaccharide challenge (P < 0.05 or 0.01). Hepatic and renal GTP-CHI mRNA expressions in the DAHP treatment group were markedly down-regulated compared with the endotoxic shock group at various intervals, and they tended to approach normal range at 12 hrs in lungs. Additionally, organ functional indexes including serum ALT, AST, BUN, Cr levels and pulmonary myeloperoxidase activity were significantly decreased in the DAHP-treated group compared to the endotoxic shock group at 0.5-24 hrs. Conclusions: These data suggest that biopterin formation is involved in the pathogenesis of endotoxin-induced acute organ injury, and inhibition of tetrahydrobiopterin synthesis pathway attenuates inflammatory response and prevents multiple organ dysfunction syndrome as well as septic shock.

Role of enteral nutrition supplemented with ebselen and EHEC in pancreatitis-associated multiple organ dysfunction in rats

To investigate potential effects of ebselen and ethylhydroxyethyl cellulose (EHEC) on the acute phase responses and the severity of multiple organ dysfunction associated with acute pancreatitis. Acute pancreatitis was induced by intraductal infusion of 5% sodium taurodeoxycholate. The increase of total protein content in the BALF was used as an indication for acute lung injury, plasma amylase for pancreatic damage, plasma bilirubin for acute liver dysfunction, and plasma creatinine for acute kidney dysfunction. Levels of interleukin (IL)-6, macrophage inflammatory protein (MIP)-2 in the BALF were determined by ELISA. There was a dose-related tendency for ebselen or EHEC alone to prevent organ dysfunction and reduce elevated plasma levels of IL-6 and ICAM-1 expression on circulating leukocytes 12 h after AP induction. The combination of ebselen and EHEC significantly prevented pancreatitis-induced multiple organ injury, IL-6 production and ICAM-1 expression in rats and exhibited better effects than either monocompound alone. The combination of ebselen and EHEC may be a new potential for treatment of acute severe pancreatitis.