Protective effects of hemin pretreatment combined with ulinastatin on septic shock in rats:

Effect of ulinastatin, a human urinary protease inhibitor, on heatstroke-induced apoptosis and inflammatory responses in rats

Ulinastatin has been demonstrated to protect against heatstroke by reducing cerebral ischemia and damage in rats. In order to extend these observations, apoptosis and systemic inflammatory responses were assessed in rats treated with ulinastatin prior to the initiation of heatstroke. Following the onset of heatstroke, histological analysis revealed that the hippocampal tissues displayed edema and damage. In addition, upregulation of malondialdehyde, inducible nitric oxide synthase (iNOS) and reactive oxygen species and downregulation of superoxide dismutase were observed compared with the respective levels in the control group. Furthermore, TUNEL staining and western blotting assays indicated that heatstroke induced cell apoptosis by increasing the Bax/Bcl-2 ratio and caspase-3 levels, and upregulating the protein expression levels of nuclear factor-κB, cyclooxygenase-2 and iNOS. However, the injury induced by heatstroke was significantly inhibited by ulinastatin pretreatment at doses of 5,000 and 10,000 IU/kg. Survival analysis of the rats subjected to heatstroke demonstrated that rats treated with ulinastatin at a dose of 10,000 IU/kg lived longer than those that did not receive ulinastatin treatment. These observations indicate that ulinastatin may protect against heatstroke by reducing apoptosis and systemic inflammatory responses.

IRG1 induced by heme oxygenase-1/carbon monoxide inhibits LPS-mediated sepsis and pro-inflammatory cytokine production

The immunoresponsive gene 1 (IRG1) protein has crucial functions in embryonic implantation and neurodegeneration. IRG1 promotes endotoxin tolerance by increasing A20 expression in macrophages through reactive oxygen species (ROS). The cytoprotective protein heme oxygenase-1 (HO-1), which generates endogenous carbon monoxide (CO), is expressed in the lung during Lipopolysaccharide (LPS) tolerance and cross tolerance. However, the detailed molecular mechanisms and functional links between IRG1 and HO-1 in the innate immune system remain unknown. In the present study, we found that the CO releasing molecule-2 (CORM-2) and chemical inducers of HO-1 increased IRG1 expression in a time- and dose-dependent fashion in RAW264.7 cells. Furthermore, inhibition of HO-1 activity by zinc protoporphyrin IX (ZnPP) and HO-1 siRNA significantly reduced expression of IRG1 under these conditions. In addition, treatment with CO and HO-1 induction significantly increased A20 expression, which was reversed by ZnPP and HO-1 siRNA. LPS-stimulated TNF-α was significantly decreased, whereas IRG1 and A20 were increased by CORM-2 application and HO-1 induction, which in turn were abrogated by ZnPP. Interestingly, siRNA against IRG1 and A20 reversed the effects of CO and HO-1 on LPS-stimulated TNF-α production. Additionally, CO and HO-1 inducers significantly increased IRG1 and A20 expression and downregulated TNF-α production in a LPS-stimulated sepsis mice model. Furthermore, the effects of CO and HO-1 on TNF-α production were significantly reversed when ZnPP was administered. In conclusion, CO and HO-1 induction regulates IRG1 and A20 expression, leading to inhibition of inflammation in vitro and in an in vivo mice model.

Ulinastatin ameliorates acute kidney injury following liver transplantation in rats and humans

Acute kidney injury (AKI) is a common complication following orthotopic liver transplantation (OLT) that evidently affects prognosis. However, no effective treatment exists for AKI. The aim of the present study was to elucidate whether ulinastatin application during OLT in humans can reduce kidney damage and improve renal function. In addition, the underlying mechanisms of ulinastatin were investigated on a rat autologous OLT (AOLT) model. In total, 60 patients undergoing an OLT were randomly selected to receive ulinastatin (U group; n=30) or saline (C group; n=30) during the OLT surgery. The patient demographics, AKI incidence rate, recovery indicators and renal injury indexes were measured during the perioperative period. In addition to the clinical trials, 40 rats were subjected to an AOLT and were divided into the control (C-R), sham-operation and ulinastatin treatment groups. Pathological renal damage, biomarkers of inflammation and oxidative stress were measured to investigate the effects and possible mechanisms of ulinastatin on AKI. In the clinical trials, ulinastatin application was shown to attenuate the incidence of AKI following OLT (P<0.05) and reduce the serum levels of cystatin C and urinary β₂ microglobulin within 24 h of the OLT (P<0.05). Furthermore, ulinastatin was found to significantly improve the recovery of patients by reducing the time spent in the intensive care unit (P<0.01 vs. C group), the ventilation time and the hemodialysis rates (P<0.05 vs. C group). In the rat AOLT model, ulinastatin application was also shown to relieve renal pathological damage by reducing the serum cystatin C and creatinine levels. Notably, the levels of tumor necrosis factor-α, interleukin-6, hydrogen peroxide and reactive oxygen species were evidently reduced, while the level of superoxide dismutase was increased in the ulinastatin groups (P<0.05, vs. C-R group). In conclusion, ulinastatin application was demonstrated to protect against AKI following OLT by inhibiting inflammation and oxidation.

Effect of ulinastatin on paraquat-induced-oxidative stress in human type II alveolar epithelial cells

BACKGROUND:

Ulinastatin (UTI) is a urinary trypsin inhibitor extracted and purified from urine of males. This study aimed to explore the effects of UTI on paraquat-induced-oxidative stress in human type II alveolar epithelial cells.

METHODS:

The human type II alveolar epithelial cells, A549 cells, were cultured in vitro. The A549 cells were treated with different concentrations of paraquat (200, 400, 600, 800, 1 000, 1 200 µmol/L) and ulinastatin(0, 2 000, 4 000, 6 000, 8 000 U/mL) for 24 hours, the cell viability was measured by cell counting kit-8 and the median lethal concentration was selected. In order to establish an in vitro model of paraquat intoxication and to determine the safe dose of ulinastatin, we calculated LD50 using cell counting kit-8 to determine the survival rate of the cells. A549 cells were divided into normal control group, paraquat group and paraquat+ulinastatin group. The levels of malondialdehyde (MDA) and myeloperoxidase (MPO) were detected by biochemistry colorimetry, while the level of reactive oxygen spies (ROS) was detected by DCFH-DA assay.

RESULTS:

The survival rate of A549 cells treated with different concentrations of paraquat decreased in a concentration-dependent manner. Whereas there was no decrease in the survival rate of cells treated with 0–4 000 U/mL ulinastatin. The levels of MDA, MPO, and ROS were significantly higher in the paraquat group than in the normal control group after 24-hour-exposure. And the survival rate of the paraquat+ulinastatin group was higher than that of the paraquat group, but lower than that of the normal control group. The levels of MDA, MPO, and ROS were lower than those of the paraquat group.

CONCLUSION:

Ulinastatin can alleviate the paraquat-induced A549 cell damage by reducing oxidative stress.

Ulinastatin activates haem oxygenase 1 antioxidant pathway and attenuates allergic inflammation

BACKGROUND AND PURPOSE

Ulinastatin (UTI), a serine protease inhibitor, was recently found to have an anti-inflammatory action. However, the mechanisms mediating this anti-inflammatory effect are not well understood. This study tested the hypothesis that UTI suppresses allergic inflammation by inducing the expression of haem oxygenase 1 (HO1).

EXPERIMENTAL APPROACH

Control mice and mice sensitized (on days 1, 9 and 14) and challenged (on days 21 to 27) with ovalbumin (OVA) were treated with UTI. The effects of UTI on basal expression of HO1 and that induced by OVA challenge were examined. The involvement of UTI-induced HO1 expression in anti-inflammatory and antioxidant effects of UTI was also evaluated.

KEY RESULTS

UTI markedly increased basal HO1 protein expression in lungs of control mice in a time- and dose-dependent manner, and augmented HO1 protein expression induced by OVA. The up-regulation of HO1 mediated by UTI in sensitized and OVA-challenged mice was associated with reduced airway inflammation, alleviated tissue injury, reduced oxidant stress and enhanced antioxidant enzyme activities. Inhibition of HO1 activity using HO1 inhibitor, zinc protoporphyrin, attenuated inhibitory effects of UTI on inflammation and oxidant stress, and its stimulant effects on antioxidant enzyme activities. Mechanistic analysis showed that UTI increased nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2), stimulated Nrf2 DNA binding activity and concomitantly up-regulated HO1 mRNA expression.

CONCLUSIONS AND IMPLICATIONS

UTI is a potent and naturally occurring inducer of HO1 expression. HO1 up-regulation contributes significantly to the anti-inflammatory and organ-protective effects of UTI, which has important research and therapeutic implications.

Effect of ERK1/2 signaling pathway in electro-acupuncture mediated up-regulation of heme oxygenase-1 in lungs of rabbits with endotoxic shock

Background

The anti-oxidative and anti-inflammatory activities of electro-acupuncture (EA), a traditional clinical method, are widely accepted, but its mechanisms are not yet well defined. In this study, we investigated the role of extracellular signal-regulated kinases1/2 (ERK1/2) pathways on electro-acupuncture – mediated up-regulation of heme oxygenase-1 (HO-1) in rabbit lungs injured by LPS-induced endotoxic shock.

Material/Methods

Seventy rabbits were randomly divided into 7 groups: group C, group M, group D, group SEAM, group EAM, group EAMPD, and group PD98059. Male New England white rabbits were given EA treatment on both sides once a day on days 1–5, and then received LPS to replicate the experimental model of injured lung induced by endotoxic shock. Then, they were killed by exsanguination at 6 h after LPS administration. The blood samples were collected for serum examination, and the lungs were removed for pathology examination, determination of wet-to-dry weight ratio, MDA content, SOD activity, serum tumor necrosis factor-α, determination of HO-1 protein and mRNA expression, and determination of ERK1/2 protein.

Results

The results revealed that after EA treatment, expression of HO-1and ERK1/2 was slightly increased compared to those in other groups, accompanied with less severe lung injury as indicated by lower index of lung injury score, lower wet-to-dry weight ratio, MDA content, and serum tumor necrosis factor-α levels, and greater SOD activity (p<0.05 for all). After pretreatment with ERK1/2 inhibitor PD98059, the effect of EA treatment and expression of HO-1 were suppressed (p<0.05 for all).

Conclusions

After electro-acupuncture stimulation at ST36 and BL13, severe lung injury during endotoxic shock was attenuated. The mechanism may be through up-regulation of HO-1, mediated by the signal transductions of ERK1/2 pathways. Thus, the regulation of ERK1/2 pathways via electro-acupuncture may be a therapeutic strategy for endotoxic shock.

Role of Nrf2/ARE pathway in protective effect of electroacupuncture against endotoxic shock-induced acute lung injury in rabbits

NF-E2 related factor 2 (Nrf2) is a major transcription factor and acts as a key regulator of antioxidant genes to exogenous stimulations. The aim of current study was to determine whether Nrf2/ARE pathway is involved in the protective effect of electroacupuncture on the injured lung in a rabbit model of endotoxic shock. A dose of lipopolysaccharide (LPS) 5 mg/kg was administered intravenously to replicate the model of acute lung injury induced by endotoxic shock. Electroacupuncture pretreatment was handled bilaterally at Zusanli and Feishu acupoints for five consecutive days while sham electroacupuncture punctured at non-acupoints. Fourty anesthetized New England male rabbits were randomized into normal control group (group C), LPS group (group L), electroacupuncture + LPS group (group EL) and sham electroacupuncture + LPS (group SEL). At 6 h after LPS administration, the animals were sacrificed and the blood samples were collected for biochemical measurements. The lungs were removed for calculation of wet-to-dry weight ratios (W/D), histopathologic examination, determination of heme oxygenase (HO)-1 protein and mRNA, Nrf2 total and nucleoprotein, as well as Nrf2 mRNA expression, and evaluation of the intracellular distribution of Nrf2 nucleoprotein. LPS caused extensive morphologic lung damage, which was lessened by electroacupuncture treatment. Besides, lung W/D ratios were significantly decreased, the level of malondialdehyde was inhibited, plasma levels of TNF-α and interleukin-6 were decreased, while the activities of superoxide dismutase, glutathione peroxidase and catalase were enhanced in the electroacupucnture treated animals. In addition, electroacupuncture stimulation distinctly increased the expressions of HO-1 and Nrf2 protein including Nrf2 total protein and nucleoprotein as well as mRNA in lung tissue, while these effects were blunted in the sham electroacupuncture group. We concluded that electroacupuncture treatment at ST36 and BL13 effectively attenuates lung injury in a rabbit model of endotoxic shock through activation of Nrf2/ARE pathway and following up-regulation of HO-1 expression.

Heme oxygenase 1 modulates thrombomodulin and endothelial protein C receptor levels to attenuate septic kidney injury

This study investigated the effects of heme oxygenase 1 (HO-1) on thrombomodulin (TM) and endothelial protein C receptor (EPCR) expression in sepsis-induced kidney injury. The role of HO-1 was evaluated in a cecal ligation and puncture (CLP)-induced model. Wistar rats were randomly assigned into four groups: sham, CLP, CLP + hemin (an HO-1 inducer), CLP + ZnPP (zinc protoporphyrin IX, an HO-1 inhibitor), and CLP + bilirubin. Compared with the sham group, the CLP group exhibited significantly elevated plasma levels of cystatin C, creatinine, urea nitrogen (blood urea nitrogen), tumor necrosis factor α, interleukin 1β, TM, and EPCR; lower plasma level of activated protein C, shorter prothrombin time and activated partial thromboplastin time; significantly increased microthrombus formation; and lower TM and EPCR mRNA and protein expression in the kidney. The administration of hemin lowered the plasma levels of cystatin C, creatinine, blood urea nitrogen, tumor necrosis factor α, interleukin 1β, TM, and EPCR; elevated plasma level of activated protein C; prolonged prothrombin time and activated partial thromboplastin time; attenuated microthrombus formation; and upregulated the expression of TM and EPCR and mRNA levels of TM and EPCR in the kidney in the CLP + hemin group. In contrast, ZnPP had the opposite effects. The results indicated that the enhanced induction of HO-1 increased the expression of TM and EPCR in the kidney and exerted an anticoagulant effect, thereby attenuating kidney injury in septic rats.

Role of HO-1 in protective effect of electro-acupuncture against endotoxin shock-induced acute lung injury in rabbits

Heme oxygenase (HO)-1 has been reported to play a great role in attenuating lung injury during endotoxic shock in our previous research. Although electro-acupuncture has been explored to reduce oxidative stress and decrease inflammatory reaction in animals with endotoxic shock, the mechanism of this effect is still unclear. The aim of this study was to determine whether HO-1 is involved in the effect of electro-acupuncture on the injured lung during endotoxic shock in rabbits. Sixty New England white rabbits were randomly divided into groups C, Z, ES, EA, AP, and EAZ. Before inducing endotoxic shock, group ES received no electro-acupuncture, while group EA received electro-acupuncture at ST36 (zusanli) and BL13 (feishu) acupoints on both sides for five days and group AP received electro-acupuncture (EA) stimulation at a non-acupoint. Groups ES, AP, EA, and EAZ received LPS to replicate the experimental model of injured lung induced by endotoxic shock, and electro-acupuncture was performed throughout the procedure with the same parameter. Groups EAZ and Z received the HO-1 inhibitor, ZnPP-IX, intraperitoneally. The animals were sacrificed by blood-letting at 6 h after LPS administration. The blood samples were collected for serum examination, and the lungs were removed for pathology examination, detection of alveolaer epithelial cell apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL assay), determination of wet to dry ratio, measurement of Evans blue (EB) contents, and determination of HO-1protein and mRNA expression. According to the results, EA at ST36 and BL13 could increase the expression of HO-1. At the same time, index of quantitative assessment (IQA) score and the number of TUNEL-positive cells decreased, while electro-acupuncture at the other points did not exert this effect, and pretreatment with ZnPP-IX in group EAZ suppressed the efficacy of electro-acupuncture preconditioning. In summary, electro-acupuncture stimulation at ST36 and BL13, while not the non-acupoint, could attenuate the lung injury during the endotoxic shock, and this effect was due to increased expression of HO-1.

Antitumor activity of hyaluronic acid-selenium nanoparticles in Heps tumor mice models

In this study, hyaluronic acid-selenium (HA-Se) nanoparticles as novel complexes were synthesized and their antitumor activities in vivo were investigated. The mice inoculated with Heps tumor were orally administered with HA-Se nanoparticles at 86.45 mg/kg (H) and 4.32 mg/kg (L) body weights as high and low doses respectively (2.20% selenium content in the HA-Se nanoparticles samples by ICP-AES) for 10 days. The transmission electron microscopy (TEM) results indicated that the HA-Se nanoparticles were spherical with mean size of 50-70 nm. The HA-Se nanoparticles could significantly reduce tumor weights at the tumor inhibition ratios of 46.92% (H) and 49.12% (L) respectively. However, in the 5-fluorouracil positive group (25 mg/kg), the tumor inhibition ratio was 61.71%. From the study, the HA-Se nanoparticles (4.32 mg/kg) significantly increased thymus and spleen relative weights, enhanced the activities of superoxide dismutase (SOD), reduced the formation of malondialdehyde (MDA) and the activities of aspartate transaminase, alanine transaminase and crea in Heps tumor mice. The results of the study indicated that the HA-Se nanoparticles are potential antitumor candidate for cancer treatment.

The effects of ulinastatin on systemic inflammation, visceral vasopermeability and tissue water content in rats with scald injury

BACKGROUND

The aim of this study was to examine whether administration of ulinastatin inhibits pro-inflammatory mediators and ameliorate visceral vasopermeability both in a rat model of major burn, and also in rat cultured endothelial cells stimulated with permeability-evoking mediators.

METHODS

Plasma levels of tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), myeloperoxidase (MPO), microvascular permeability, and water content of organ tissues were evaluated in a rodent model of a 55% TBSA full-thickness scald injury. Microvascular permeability was also evaluated with a cultured pulmonary microvascular endothelial cells (PMECs) monolayer after stimulation with trypsin, bradykinin, histamine, prostaglandin E2 and burn serum.

RESULTS

We found that the plasma levels of TNF-α, CRP, MPO, vascular permeability and water content of heart, lung, kidney, and small intestine tissues were significantly increased in animals after scald injury, and administration of ulinastatin lowered the levels TNF-α, CRP, MPO, vascular permeability and water content of those organ tissues. In vitro, ulinastatin lowered the levels of TNF-α, interleukin-6 (IL-6) and attenuated permeability in PMEC monolayers after being stimulated with burn serum or trypsin, but not by bradykinin, histamine or prostaglandin E2.

CONCLUSIONS

These results indicate that ulinastatin attenuates the systemic inflammatory response and visceral vasopermeability both in vivo and vitro, and may serve as a therapeutic agent for prevention of systemic inflammatory response and leakage of fluid into tissue after major burn.

In vitro and in vivo antitumor activity of Macrothelypteris torresiana and its acute/subacute oral toxicity

The aim of this study was to evaluate the antitumor potential of Macrothelypteris torresiana by studying in vitro antitumor activity of the protoapigenone, as well as in vivo antitumor activity and acute/subacute oral toxicity of the total flavonoid fraction from the roots of M. torresiana. Considering that the protoapigenone is a main constituent of the total flavonoid fraction and it might play a key role in the antitumor activity of M. torresiana, the MTT assay was used to investigate the in vitro antitumor activity of the protoapigenone. Our study revealed that the protoapigenone of M. torresiana showed significant antitumor activity towards Hep G2, Tca-8113, MCF-7, M5 and K562 with IC(50) values of 2.3, 0.6, 0.8, 0.3 and 0.9 μg/ml, respectively. The antitumor potential of the total flavonoid fraction was evaluated using preparations 1, 2 and 3, which were prepared by total flavonoid fraction directly diluted with sterile saline, dissolved using sodium carboxymethyl cellulose (CMC-Na) and included by hydroxypropyl-β-cyclodextrin, respectively. These were investigated in vivo using mouse sarcoma S-180 in BALB/c mice after completing tumor inoculation for 24h. Pronounced antitumor activity was observed in the treated groups for preparations 2 and 3, and the high and medium doses in particular showed very high inhibition ratio of tumor growth (>50%). No significant difference was observed when compared to the positive control group (5-fluorouracil). The acute/subacute oral toxicity test was performed, and the results of acute oral toxicity showed that the LD(50) values of preparations 2 and 3 were 2.76 and 0.87 g/kg body wt., respectively. According to the results of the subacute oral toxicity study, the total flavonoid fraction had low toxicity. The overall results of this study suggest that the total flavonoid fraction from the roots of M. torresiana shows significant antitumor activity and represents a potential source of medicine for the treatment of cancer.

Effect of heme oxygenase-1 on the kidney during septic shock in rats

The aim of this study was to clarify the effect of heme oxygenase (HO)-1 on the kidney during septic shock in rats. Eighty healthy and clean Sprague-Dawley rats were randomly divided into 4 groups: control group (group C) , septic shock group (group SS) , lipopolysaccharide plus ZnPP-IX group (group LZ) , and ZnPP-IX (group Z) . The plasma levels of COHb, Cr, and BUN; the urine levels of gamma-GTP, alpha1-MG, RBP, and NAG; and MDA content, SOD activity; HO-1mRNA; HO-2mRNA; HO-1 protein; and HO-2 protein from kidney were measured. The plasma levels of Cr and BUN; the urine levels of gamma-GTP, alpha1-MG, RBP, and NAG; and MDA content from kidney in group SS were obviously higher than in group C and Z (both P < 0.05), respectively, but lower than in group LZ (both P < 0.05), respectively. In contrast, the plasma levels of COHb and SOD activity from kidney in group SS were obviously lower than those in group C and Z (both P < 0.05), respectively, but higher than in group LZ (both P < 0.05), respectively. The HO-1mRNA and HO-1 protein of nephridial tissue in group LZ were obviously higher than in group C and Z, respectively (both P < 0.05), but lower than in group SS, respectively (both P < 0.05). There were no significant differences of HO-2mRNA and HO-2 protein among these 4 groups (both P > 0.05). It is concluded that upregulation of the HO-1 protein might contribute to the protection of kidney during septic shock in rats.

Heme-oxygenase-1 induction and carbon monoxide-releasing molecule inhibit lipopolysaccharide (LPS)-induced high-mobility group box 1 release in vitro and improve survival of mice in LPS- and cecal ligation and puncture-induced sepsis model in vivo

We examined our hypothesis that heme-oxygenase-1 (HO-1)-derived carbon monoxide (CO) inhibits the release of high-mobility group box 1 (HMGB1) in RAW264.7 cells activated with lipopolysaccharide (LPS) in vitro and in LPS- or cecal ligation and puncture (CLP)-induced septic mice in vivo, so that HO-1 induction or CO improves survival of sepsis in rodents. We found that pretreatment with HO-1 inducers (hemin, cobalt protoporphyrin IX) or transfection of HO-1 significantly inhibited HMGB1 release, which was blocked by HO-1 small interfering RNA, in cells activated by LPS. Carbon monoxide-releasing molecule 2 (CORM-2) but not bilirubin or deferoxamine inhibited HMGB1 release in LPS-activated macrophages. Oxyhemoglobin reversed the effect of HO-1 inducers on HMGB1 release. Translocation of HMGB1 from nucleus to cytosol was significantly inhibited by HO-1 inducers, CORM-2, or HO-1 transfection. Neutralizing antibodies to tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, interferon-beta, and N(omega)-nitro-L-arginine methyl ester hydrochloride but not N-[2-(cyclohexyloxyl)-4-nitrophenyl]-methane sulfonamide (NS-398) significantly inhibited HMGB1 release in LPS-activated cells. Production of TNF-alpha, IL-1beta, and IFN-beta was significantly reduced by pretreatment of HO-1 inducers, CORM-2, or HO-1 transfection in LPS-activated cells. Plasma levels of HMGB1 in mice challenged with LPS or CLP were significantly reduced by the administration of HO-1 inducers or CORM-2, which was accompanied by either reduction (pretreatment) or no change (delayed administration) of serum TNF-alpha and IL-1beta levels. Regardless of pretreatment or delayed administration, CORM-2 and hemin rescued mice from lethal endotoxemia and sepsis induced by LPS or CLP. Taken together, we concluded that HO-1-derived CO reduces HMGB1 release in LPS-activated cells and LPS- or CLP-induced animal model of sepsis.