Expert consensus on the monitoring and treatment of sepsis-induced immunosuppression.

Emerged evidence has indicated that immunosuppression is involved in the occurrence and development of sepsis. To provide clinical practice recommendations on the immune function in sepsis, an expert consensus focusing on the monitoring and treatment of sepsis-induced immunosuppression was developed. Literature related to the immune monitoring and treatment of sepsis were retrieved from PubMed, Web of Science, and Chinese National Knowledge Infrastructure to design items and expert opinions were collected through an online questionnaire. Then, the Delphi method was used to form consensus opinions, and RAND appropriateness method was developed to provide consistency evaluation and recommendation levels for consensus opinions. This consensus achieved satisfactory results through two rounds of questionnaire survey, with 2 statements rated as perfect consistency, 13 as very good consistency, and 9 as good consistency. After summarizing the results, a total of 14 strong recommended opinions, 8 weak recommended opinions and 2 non-recommended opinions were produced. Finally, a face-to-face discussion of the consensus opinions was performed through an online meeting, and all judges unanimously agreed on the content of this consensus. In summary, this expert consensus provides a preliminary guidance for the monitoring and treatment of immunosuppression in patients with sepsis.

Recent advances in neutrophil chemotaxis abnormalities during sepsis.

Sepsis remains one of the leading causes of death globally, in spite of advanced developments in intensive care and better understandings of pathophysiology related to sepsis. There is no special treatment or drug available for sepsis, currently. Under normal circumstances, neutrophil is a major player in acute infection control. However, during sepsis, the migration abilities and antimicrobial functions of neutrophils are impaired, resulting in a dysregulated immune response. Recent studies have indeed demonstrated that blocking or reversing neutrophil migration and impaired antibacterial function can improve the outcomes in septic animal models. This article systemically synthesized information regarding related factors and signaling involved in the functions of neutrophils in sepsis. This review also discussed the possibility that neutrophils be used as a marker for specific diagnosis and/or prediction of the outcomes of sepsis.

A narrative review of research progress on the relationship between hypoxia-inducible factor-2α and wound angiogenesis.

OBJECTIVE: This article aims to pay attention to the latest research on the expression, activation and function of hypoxia-inducible factor-2α (HIF-2α) under hypoxia and non-hypoxia conditions, and summarizes the current knowledge about the interaction between hypoxia-inducible factor-2 and angiogenesis, hoping to understand its actions in physiology and disease, with the goal of providing a new strategy for the diagnosis and treatment of wounds. BACKGROUND: Wound healing is a complex and continuous process, involving coagulation, inflammation, angiogenesis, new tissue formation and extracellular matrix remodeling. Of these, angiogenesis is an essential step. One of the main reasons for non-healing or delayed healing of wounds in peripheral vascular diseases and diabetes is the reduced ability to regenerate microvessels through the process of angiogenesis, which has become the focus of new methods for treating chronic wounds. HIF-2α regulates many aspects of angiogenesis, including vascular maturation, cell migration, proliferation and metastasis. METHODS: Throughout extensive search of PubMed, summarize the medical research on HIF-2α to 2020. CONCLUSIONS: HIF-2α is necessary for normal embryonic development by stimulating the expression of angiogenic factors, such as vascular endothelial growth factor (VEGF). It is essential for the formation of new blood vessels in physiological and pathophysiological environments. Targeting HIF-2α in wound healing has much clinical significance for tissue repair.

A novel role of kukoamine B: Inhibition of the inflammatory response in the livers of lipopolysaccharide-induced septic mice via its unique property of combining with lipopolysaccharide.

Kukoamine B (KB), derived from the traditional Chinese herb cortex Lycii, exerts anti-inflammatory effects due to its potent affinity with lipopolysaccharide (LPS) and CpG DNA; however, little is known regarding whether the in vivo administration of KB can effectively inhibit inflammation in septic mice. The present study thus aimed to investigate the inhibitory effects of KB on the inflammatory response in the livers of LPS-induced septic mice. KB treatment in the LPS-induced septic mice significantly decreased the plasma level of LPS. In addition, KB protected against liver injury, as confirmed by improved histology and decreased aminotransferase levels in the serum. Further experiments revealed that KB attenuated liver myeloperoxidase activity and reduced the expression of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1. These effects were accompanied by decreases in the levels of tumor necrosis factor α and interleukin-1ß in the liver tissue. In parallel, the activity of nuclear factor-κ-gene binding (NF-κB) in the livers of LPS-induced septic mice was markedly inhibited with KB treatment. In combination, these results demonstrate that KB inhibits inflammation in septic mice by reducing the concentrations of plasma LPS, decreasing leukocyte sequestration and interfering with NF-κB activation, and, therefore, suppressing the pro-adhesive phenotype of endothelial cells.

Exogenous carbon monoxide suppresses Escherichia coli vitality and improves survival in an Escherichia coli-induced murine sepsis model.

AIM: Endogenous carbon monoxide (CO) has been shown to modulate inflammation and inhibit cytokine production both in vivo and in vitro. The aim of this study was to examine whether exogenous carbon monoxide could suppress the vitality of Escherichia coli (E coli) and improve the survival rate in an E coli-induced murine sepsis model. METHODS: ICR mice were infected with E coli, and immediately injected intravenously with carbon monoxide releasing molecule-2 (CORM-2, 8 mg/kg) or inactive CORM-2 (8 mg/kg). The survival rate was monitored 6 times daily for up to 36 h. The blood samples, liver and lung tissues were collected at 6 h after the infection. Bacteria in peritoneal lavage fluid, blood and tissues were enumerated following culture. Tissue iNOS mRNA expression was detected using RT-PCR. NF-κB expression was detected with Western blotting. RESULTS: Addition of CORM-2 (200 and 400 µmol/L) into culture medium concentration-dependently suppressed the growth of E coli and decreased the colony numbers, but inactive CORM-2 had no effect. Treatment of the infected mice with CORM-2 significantly increased the survival rate to 55%, while all the infected mice treated with inactive CORM-2 died within 36 h. E coli infection caused severe pathological changes in liver and lungs, and significantly increased serum transaminases, lipopolysaccharide, TNF-α and IL-1ß levels, as well as myeloperoxidase activity, TNF-α and IL-1ß levels in the major organs. Meanwhile, E coli infection significantly increased the number of colonies and the expression of iNOS mRNA and NF-κB in the major organs. All these abnormalities were significantly attenuated by CORM-2 treatment, while inactive CORM-2 was ineffective. CONCLUSION: In addition directly suppressing E coli, CORM-2 protects the liver and lungs against E coli-induced sepsis in mice, thus improving their survival.

Regulatory effect and mechanisms of carbon monoxide-releasing molecule II on hepatic energy metabolism in septic mice.

AIM: To investigate the possible mechanisms of exogenous carbon monoxide-releasing molecule II (CORM-2) intervention on hepatic energy metabolism in experimental sepsis. METHODS: Forty-eight C57BL/6 mice were randomly divided into four groups (n = 12): sham group; cecal ligation and puncture (CLP) group; CLP + CORM-2 group and CLP + iCORM-2 (inactive CORM-2) group. Survival rates were determined after 72 h. Twenty-four similarly treated mice (n = 6 in each group) were assayed for post-operative continuous blood glucose in the first 36 h. Thirty-six similarly treated mice (n = 9 in each group) underwent micro-positron emission tomography (PET) scanning after tail vein injection of (18)F-fluorodeoxyglucose (FDG) 24 h after operation. Plasma and liver specimens were collected for assay of liver pathology, alanine transaminase (ALT) and aspartate transaminase (AST) activities. Hepatic glucokinase activity, lactic acid levels and mitochondrial swelling were also determined. RESULTS: Improved survival was observed in CORM-2 treated mice. Both the CLP and CLP + CORM-2 groups had sustained low blood glucose levels within the first post-operative 36 h. (18)F-FDG micro-PET images showed abnormally high levels of hepatic glucose metabolism (standardized uptake value) in the CLP group (2.76 ± 0.39 vs 0.84 ± 0.14, P < 0.01), which declined to normal levels after CORM-2 intervention (1.29 ± 0.32 vs 2.76 ± 0.39, P < 0.05). glucokinase activity was markedly increased in the CLP group (6.38 ± 0.56 U/g vs 4.60 ± 0.21 U/g, P < 0.01), but was normal after CORM-2 intervention (4.74 ± 0.14 U/g vs 6.38 ± 0.56 U/g, P < 0.05). CORM-2 suppressed plasma lactic acid levels (4.02 ± 0.02 mmol/L vs 7.72 ± 2.37 mmol/L, P < 0.05) and protected hepatic mitochondria in CLP mice. CORM-2 intervention also reduced elevated plasma AST (199.67 ± 11.08 U/L vs 379.67 ± 16.34 U/L, P < 0.05) and ALT (63.67 ± 12.23 U/L vs 112.67 ± 9.74 U/L, P < 0.05) activities in CLP mice. CONCLUSION: The release of CO molecules by CORM-2 protects mitochondria and maintains a stable level of hepatic glucose metabolism. Thus, CORM-2 improves liver function and survival in septic mice.

[Effects of exogenous carbon monoxide-releasing molecules 2 on the vitality and toxicity of E.coli].

OBJECTIVE: To explore the effects of exogenous carbon monoxide-releasing molecules 2 (CORM-2) on the vitality and toxicity of E. coli ATCC 25922, and to analyze the potential mechanism. METHODS: (1) In vitro experiments. Standard strains of E. coli ATCC 25922 were divided into groups A (without addition), B, C, D, and E according to the random number table, and then the latter 4 groups were respectively cultured with 1.2 mmol/L CORM-2, 1.6 mmol/L CORM-2, 1.2 mmol/L inactive CORM-2 (iCORM-2), 1.6 mmol/L iCORM-2, with six samples in each group. After being cultured for 0, 3, 5, 8, 10, 12, 16, 20, 24, 27, 30, 48 hours, proliferative vitality of E. coli was examined (denoted as absorption value under 600 nm wavelength), and bacteria number was counted. Other standard strains of E. coli ATCC 25922 were divided into groups F (without addition) and G (cultured with 0.8 mmol/L CORM-2), the expressions of genes fliA, dnaK, marA, and waaQ related to E. coli were detected by quantitative real-time (qRT)-PCR. (2) In vivo experiments. Other standard strains of E. coli ATCC 25922 were grouped as A', B', C', D', and E' and treated with the same method as that in groups A, B, C, D, and E, and 0.5 mL bacterial liquid of each group were collected when the absorption value of bacterial liquid in group A' was equal to 0.4 (under 600 nm wavelength). Seventy-two C57BL/6 mice were divided into groups, namely blank control (without treatment), H, I, J, K, and L according to the random number table, with 12 mice in each group. The mice in the latter 5 groups were intraperitoneally injected with 0.5 mL bacterial suspension of groups A', B', C', D', and E' respectively. After injection, general condition of mice in groups H, I, J, K, and L was observed. The serum levels of TNF-α and IL-6 were determined at post injection hour (PIH) 6, 12. The liver and lung samples were harvested for determination of myeloperoxidase (MPO) activity at PIH 12. The same process was carried out in blank control group. Data were processed with repeated measure analysis of variance (ANOVA), factorial design ANOVA, one-way ANOVA, and t test. RESULTS: (1) In vitro experiments. Compared with those of groups A and D, the proliferative vitality and bacteria number of E. coli in group B were all decreased (with F values respectively 1170.80, 217.52, P values all below 0.01). Compared with those of groups A and E, the proliferative vitality and bacteria number of E. coli in group C were also obviously decreased (with F values respectively 7948.34, 14 432.85, P values all below 0.01). Compared with those in group F, the expression of fliA was downregulated, while the expressions of dnaK, marA, and waaQ were upregulated in group G (with t values 30.28, -165.54, -168.88, -187.28, P values all below 0.01). (2) In vivo experiments. Symptoms including listlessness and tachypnea were observed in mice in groups H, K, and L, and they were ameliorated or not obvious in groups I and J. At PIH 6, the serum levels of TNF-α and IL-6 in groups H and K were respectively (647.3 ± 3.8) pg/mL, (3.44 ± 0.22) ng/mL and (639.3 ± 0.8) pg/mL, (2.47 ± 0.32) ng/mL, which were obviously higher than those in group I [(124.6 ± 10.7) pg/mL, (1.03 ± 0.16) ng/mL, with t values from 15.22 to 84.03, P values all below 0.01]. The serum levels of TNF-α and IL-6 in group J at PIH 6, 12 were also obviously decreased as compared with those in groups H and L (with t values from 19.27 to 245.34, P values all below 0.01). MPO activity of liver and lung tissues were significantly attenuated in group I at PIH 12 as compared with those in groups H and K, and it was also attenuated in group J when compared with those in groups H and L (with t values respectively from 17.36 to 18.92 and 2.35 to 3.61, P values all below 0.01). CONCLUSIONS: CORM-2 can obviously inhibit the vitality and toxicity of E. coli, which might be attributable to regulation of expressions of genes fliA, dnaK, marA, and waaQ of E. coli.

[Multi-center clinical trial of FLAMIGEL (hydrogel dressing) for the treatment of residual burn wound].

OBJECTIVE: To evaluate the effect of FLAMIGEL (hydrogel dressing) on the repair of residual burn wound. METHODS: Sixty burn patients with residual wounds hospitalized in 6 burn units from November 2011 to May 2012 were enrolled in the multi-center, randomized, and self-control clinical trial. Two residual wounds of each patient were divided into groups T (treated with FLAMIGEL) and C (treated with iodophor gauze) according to the random number table. On post treatment day (PTD) 7 and 14, wound healing rate was calculated, with the number of completely healed wound counted. The degree of pain patient felt during dressing change was evaluated using the visual analogue scale (VAS). The mean numbers of wounds with score equal to zero, more than zero and less than or equal to 3, more than 3 and less than or equal to 6, more than 6 and less than or equal to 10 were recorded respectively. Wound secretion or exudate samples were collected for bacterial culture, and the side effect was observed. Data were processed with repeated measure analysis of variance, t test, chi-square test, and nonparametric rank sum test. RESULTS: Wound healing rate of groups T, C on PTD 7 was respectively (67 ± 24)%, (45 ± 25)%, and it was respectively (92 ± 16)%, (72 ± 23)% on PTD 14. There was statistically significant difference in wound healing rate on PTD 7, 14 between group T and group C (F = 32.388, P < 0.01). Ten wounds in group T and four wounds in group C were healed completely on PTD 7, with no significant difference between them (χ(2) = 0, P > 0.05). Forty-two wounds in group T and seven wounds in group C healed completely on PTD 14, with statistically significant difference between them (χ(2) = 42.254, P < 0.01). Patients in group T felt mild pain during dressing change for 37 wounds, with VAS score higher than zero and lower than or equal to 3. Evident pain was observed in patients of group C during dressing change for 43 wounds, and it scored higher than 3 and less than or equal to 6 by VAS evaluation. There was statistically significant difference in mean number of wounds with different grade of VAS score between group T and group C (Z = -4.638, P < 0.01). Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, E. coli, Baumanii, and Staphylococcus epidermidis were all detected in both groups, but there was no statistical difference between group T and group C (χ(2) = 0.051, P > 0.05). No side effect was observed in either of the two groups during the whole trial. CONCLUSIONS: FLAMIGEL can accelerate the healing of residual burn wounds and obviously relieve painful sensation during dressing change.

Exogenous carbon monoxide attenuates inflammatory responses in the small intestine of septic mice.

AIM: To determine whether the carbon monoxide (CO)-releasing molecules (CORM)-liberated CO suppress inflammatory responses in the small intestine of septic mice. METHODS: The C57BL/6 mice (male, n = 36; weight 20 ± 2 g) were assigned to four groups in three respective experiments. Sepsis in mice was induced by cecal ligation and puncture (CLP) (24 h). Tricarbonyldichlororuthenium (II) dimer (CORM-2) (8 mg/kg, i.v.) was administrated immediately after induction of CLP. The levels of inflammatory cytokines [interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α)] in tissue homogenates were measured with enzyme-linked immunosorbent assay. The levels of malondialdehyde (MDA) in the tissues were determined. The levels of nitric oxide (NO) in tissue homogenate were measured and the expression levels of intercellular adhesion molecule 1 (ICAM-1) and inducible nitric oxide synthase (iNOS) in the small intestine were also assessed. NO and IL-8 levels in the supernatants were determined after the human adenocarcinoma cell line Caco-2 was stimulated by lipopolysaccharide (LPS) (10 g/mL) for 4 h in vitro. RESULTS: At 24 h after CLP, histological analysis showed that the ileum and jejunum from CLP mice induced severe edema and sloughing of the villous tips, as well as infiltration of inflammatory cells into the mucosa. Semi-quantitative analysis of histological samples of ileum and jejunum showed that granulocyte infiltration in the septic mice was significantly increased compared to that in the sham group. Administration of CORM-2 significantly decreased granulocyte infiltration. At 24 h after CLP, the tissue MDA levels in the mid-ileum and mid-jejunum significantly increased compared to the sham animals (103.68 ± 23.88 nmol/mL vs 39.66 ± 8.23 nmol/mL, 89.66 ± 9.98 nmol/mL vs 32.32 ± 7.43 nmol/mL, P < 0.01). In vitro administration of CORM-2, tissue MDA levels were significantly decreased (50.65 ± 11.46 nmol/mL, 59.32 ± 6.62 nmol/mL, P < 0.05). Meanwhile, the tissue IL-1ß and TNF-α levels in the mid-ileum significantly increased compared to the sham animals (6.66 ± 1.09 pg/mL vs 1.67 ± 0.45 pg/mL, 19.34 ± 3.99 pg/mL vs 3.98 ± 0.87 pg/mL, P < 0.01). In vitro administration of CORM-2, tissue IL-1ß and TNF-α levels were significantly decreased (3.87 ± 1.08 pg/mL, 10.45 ± 2.48 pg/mL, P < 0.05). The levels of NO in mid-ileum and mid-jejunum tissue homogenate were also decreased (14.69 ± 2.45 nmol/mL vs 24.36 ± 2.97 nmol/mL, 18.47 ± 2.47 nmol/mL vs 27.33 ± 3.87 nmol/mL, P < 0.05). The expression of iNOS and ICAM-1 in the mid-ileum of septic mice at 24 h after CLP induction significantly increased compared to the sham animals. In vitro administration of CORM-2, expression of iNOS and ICAM-1 were significantly decreased. In parallel, the levels of NO and IL-8 in the supernatants of Caco-2 stimulated by LPS was markedly decreased in CORM-2-treated Caco-2 cells (2.22 ± 0.12 nmol/mL vs 6.25 ± 1.69 nmol/mL, 24.97 ± 3.01 pg/mL vs 49.45 ± 5.11 pg/mL, P < 0.05). CONCLUSION: CORM-released CO attenuates the inflammatory cytokine production (IL-1ß and TNF-α), and suppress the oxidative stress in the small intestine during sepsis by interfering with protein expression of ICAM-1 and iNOS.

[Inhibitory effect of extrinsic CO-releasing molecules-2 (CORM-2) on inflammatory responses in mice with LPS-induced acute lung injury].

OBJECTIVE: To investigate the effects of extrinsic CO-releasing molecules-2 (CORM-2) on attenuating pulmonary injury and the inflammatory response in LPS-induced acute lung injury of mice. METHODS: Fifty-three mice were assigned to four groups. Mice in sham group (n= 8) underwent sham inhalation, whereas mice in ALI (n= 15) received inhalation of LPS for 30 min, mice in ALI+iCORM (n= 15) underwent LPS inhalation with immediate administration of inactive CORM-2 (8 mg/kg, i.v.), mice in ALI+CORM (n= 15) underwent LPS inhalation with immediate administration of CORM-2 (8 mg/kg, i.v.). PMN accumulation (MPO assay) in mice lungs and TNF-α and IL-1 ß in BAL fluid were determined. Activation of NF-kB and expression level of ICAM-1 in the lung were assessed. RESULT: Treatment of ALI mice with CORM-2 attenuated PMN accumulation and prevented activation of NF-kB in the lung. This was accompanied by a decrease of the expression of ICAM-1. In parallel, CORM-2 markedly decreased the production of inflammatory mediators in BAL fluid. CONCLUSION: CORM-2 attenuates the inflammatory response in the lung of LPS-induced ALI by decreasing leukocyte sequestration and interfering with NF-kB activation, expression of ICAM-1 and therefore suppressing endothelial cells pro-adhesive phenotype.

[Inhibitive effect of exogenous carbon monoxide-releasing molecules 2 on the activation of Janus kinase/signal transducer and activator of transcription pathway in sepsis].

OBJECTIVE: To study the inhibitive effect of exogenous carbon monoxide-releasing molecules 2 (CORM-2) on the activation of Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway in sepsis. METHODS: RAW264.7 cells were divided into normal control group, LPS group (10 mg/mL LPS, the same concentration below), LPS + inactive CORM-2 (iCORM-2) group, LPS + 50 mmol/L CORM-2 group, and LPS + 100 mmol/L CORM-2 group. TNF-alpha level in the supernatant was determined with ELISA, and the phosphorylation levels of JAK1 and JAK3 were determined with Western blot. Thirty-five male BALB/c mice were divided into normal control group, cecal ligation and puncture (CLP) group, CLP + iCORM-2 (8.0 mg/kg) group and CLP + CORM-2 group (8.0 mg/kg) according to the random number table. Mice in CLP + CORM-2 group were treated the same as mice in CLP group except for administration of CORM-2 after CLP. The plasma levels of TNF-alpha, IL-1beta, and the phosphorylation levels of JAK1, JAK3 in liver tissue were determined with ELISA 24 hours post CLP. Data were processed with t test. RESULTS: Compared with that of normal control group [(1.9 +/- 0.3) pg/mL], the TNF-alpha level [(8.2 +/- 2.7) pg/mL, t = 2.844, P < 0.01] and phosphorylation levels of JAK1, JAK3 in LPS group increased significantly; while TNF-alpha levels in LPS + 50 mmol/L CORM-2 and LPS + 100 mmol/L CORM-2 groups decreased obviously as compared with that of LPS group [(5.7 +/- 1.4), (3.2 +/- 0.9) pg/mL, with t value respectively 2.104 and 2.363, P values all below 0.05], and it was the same with phosphorylation levels of JAK1, JAK3 in a dose-dependent manner. Compared with those of normal control group, plasma levels of TNF-alpha and IL-1beta and phosphorylation levels of JAK1, JAK3 in liver tissue significantly increased in CLP group (with t value respectively 2.916 and 2.796, and P values all below 0.05); while plasma levels of TNF-alpha and IL-1beta and the phosphorylation levels of JAK1, JAK3 in liver tissue decreased significantly in CLP + CORM-2 group (with t value respectively 2.115 and 2.398, and P values all below 0.05). CONCLUSIONS: Exogenous CORM-2 can obviously inhibit the phosphorylation of JAKs molecules and then inhibit the activation of JAK/STAT signal pathway in sepsis, and decrease the expression of downstream cytokines to effectively prevent cascade reaction in the inflammatory response after severe infection.

[Inhibitive effect of exogenous carbon monoxide-releasing molecules 2 on tissue factor expression in sepsis].

OBJECTIVE: To explore the inhibitive effects of exogenous carbon monoxide-releasing molecules 2 (CORM-2) on expression of tissue factor (TF) in sepsis. METHODS: Human umbilical vein endothelial cells (HUVEC) were cultured with trypsin digestion method, which were divided into NC group (with normal treatment), LPS group (with culture of 10 microg/mL LPS), LD group (with 10 microg/mL LPS and DMSO in co-culture), LC1 group (with 10 microg/mL LPS and 10 micromol/L CORM-2 in co-culture), LC2 group (with 10 microg/mL LPS and 50 micromol/L CORM-2 in co-culture), LC3 group (with 10 microg/mL LPS and 100 micromol/L CORM-2 in co-culture). After culture for 4 hours, TF activity, TF protein expression, nuclear factor-kappaB (NF-kappaB) activity were examined. Forty-five C57 BL/6 male mice were randomly divided into NC (without treatment, n = 5), CLP (n = 5) and CLP + CORM-2 (with treatment of 8 mg/kg CROM-2 after CLP, n = 5) groups. The serum samples in CLP, CLP + CORM-2 groups were collected at 2, 6, 12 and 24 post operation hour ( POH, 5 mice at each time point) for determination of TF and TFPI levels,which were also examined in NC group. RESULTS: Compared with those of NC group, TF activity increased (P < 0.01) , TF protein expression and NF-KB activity also increased in LPS group. Compared with those of LPS group, above indices were decreased in LC1, LC2, LC3 groups. The serum level of TF in CLP group at 6 POH was higher than that of NC group (80.0 +/- 11.9 pg/mL vs 58.4 +/- 6.9 pg/mL, P < 0.05), peaked at 12 POH, and still higher than that of NC group at 24 POH, while the serum level of TFPI showed no obvious difference in NC and CLP groups. Compared with that of NC group, TFPI levels obviously increased in CLP + CORM-2 group at 6, 12 POH (23.7 +/-3.5 ng/mL, 24.4 +/- 5.0 ng/mL vs 12.4 +/- 2.8 ng/mL, P < 0.05). CONCLUSIONS: Exogenous CORM can obviously inhibit TF and NF-KB activity,decrease TF protein expression. Meanwhile, it can also decrease serum level of TF, and increase serum level of TFPI, preventing activation of procoagulant system, balancing procoagulant and anticoagulant system in sepsis.

Suppression of inflammatory cytokine production and oxidative stress by CO-releasing molecules-liberated CO in the small intestine of thermally-injured mice.

AIM: To determine whether carbon monoxide (CO)-releasing molecules-liberated CO suppress inflammatory cytokine production and oxidative stress in the small intestine of burnt mice. METHODS: Twenty-eight mice were assigned to 4 groups. The mice in the sham group (n=7) underwent sham thermal injury, whereas the mice in the burn group (n=7) received 15% total body surface area full-thickness thermal injury, the mice in the burn+CO-releasing molecules (CORM)-2 group (n=7) underwent the same injury with immediate administration of CORM-2 (8 mg/kg, i.v.), and the mice in the burn+inactivated CORM (iCORM)-2 group (n=7) underwent the same injury with immediate administration of iCORM-2. The levels of inflammatory cytokines in the tissue homogenates were measured by ELISA. The levels of malondialdehyde (MDA), nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS) in the small intestine were also assessed. In the in vitro experiment, Caco-2 cells were stimulated by experimental mouse sera (50%, v/v) for 4 h. Subsequently, the levels of interleukin (IL)-8 and NO in the supernatants were assessed. Reactive oxygen species (ROS) generation in Caco-2 cells was also measured. RESULTS: The treatment of burnt mice with CORM-2 significantly attenuated the levels of IL-1beta, TNF-alpha, MDA, and NO in tissue homogenates. This was accompanied by a decrease of iNOS expression. In parallel, the levels of IL-8, NO, and intracellular ROS generation in the supernatants of Caco-2 stimulated by the CORM-2-treated burnt mouse sera was markedly decreased. CONCLUSION: CORM-released CO attenuates the production of inflammatory cytokines, prevents burn-induced ROS generation, and suppresses the oxidative stress in the small intestine of burnt mice by interfering with the protein expression of iNOS.

CO liberated from CORM-2 modulates the inflammatory response in the liver of thermally injured mice.

AIM: To explore the effects of CO-releasing molecules [tricarbonyldichlororuthenium (II) dimer, CORM-2]-liberated CO on attenuation of inflammatory responses in liver of an experimental animal model of thermal injury and to investigate the associated potential mechanisms. METHODS: Thirty-six mice were assigned to three groups in three respective experiments. In each experiment, mice in sham group (n=4) received sham thermal injury, whereas mice in burn group (n=4) received a 15% of total body surface area (TBSA) full-thickness thermal injury, and mice in burn+CORM-2 group (n=4) received the same thermal injury with immediate administration of CORM-2 (8 mg/kg, iv). Hepatic tissue sections were stained with hematoxylin and eosin and examined under a light microscope. Levels of aminotransferases (ALT and AST) and nitric oxide (NO) were measured by biochemical methods. Tumor necrosis factor-alpha (TNF-alpha) and interleukin (IL-1beta) activity, and the protein expression of iNOS and HO-1 in serum and tissue homogenates were assessed. In in vitro experiments, Kupffer cells were stimulated with LPS (10 microg/mL) for 4 h in the presence or absence of CORM-2 (10-100 micromol/L). Subsequently, the expression levels of TNF-alpha and NO production were assessed. RESULTS: Pro-inflammatory mediators (TNF-alpha, IL-1beta, NO) in serum and liver homogenates of thermally injured mice were significantly reduced by CORM-2 administration. This was accompanied by a decrease in the expression of iNOS while an increase in the expression of HO-1 in the liver tissue. In parallel, the concentrations of TNF-alpha and NO in supernatants of LPS-stimulated Kupffer cells co-incubated with CORM-2 (10-100 micromol/L) were also markedly decreased. Histological examination demonstrated that CORM-2 could attenuate the leukocytes infiltration to the liver tissue. CONCLUSION: CORM-released CO modulates liver inflammation and significantly protects liver injury in burn mice by inhibiting the expression of iNOS and NO production, down-regulating the expression of pro-inflammatory mediators (TNF-alpha, IL-1beta).

Carbon liberated from CO-releasing molecules attenuates leukocyte infiltration in the small intestine of thermally injured mice.

AIM: To determine whether Carbon (CO) liberated from CO-releasing molecules attenuates leukocyte infiltration in the small intestine of thermally injured mice. METHODS: Thirty-six mice were assigned to four groups. Mice in the sham group (n = 9) were underwent to sham thermal injury; mice in the burn group (n = 9) received 15% total body surface area full-thickness thermal injury; mice in the burn + CORM-2 group (n = 9) were underwent to the same thermal injury with immediate administration of tricarbonyldichlororuthenium (II) dimer CORM-2 (8 mg/kg, i.v.); and mice in the burn+DMSO group (n = 9) were underwent to the same thermal injury with immediate administration of 160 muL bolus injection of 0.5% DMSO/saline. Histological alterations and granulocyte infiltration of the small intestine were assessed. Polymorphonuclear neutrophil (PMN) accumulation (myeloperoxidase assay) was assessed in mice mid-ileum. Activation of nuclear factor (NF)-kappa B, expression levels of intercellular adhesion molecule-1 (ICAM-1) and inducible heme oxygenase in mid-ileum were assessed. RESULTS: Treatment of thermally injured mice with CORM-2 attenuated PMN accumulation and prevented activation of NF-kappa B in the small intestine. This was accompanied by a decrease in the expression of ICAM-1. In parallel, burn-induced granulocyte infiltration in mid-ileum was markedly decreased in the burn mice treated with CORM-2. CONCLUSION: CORM-released CO attenuates leukocyte infiltration in the small intestine of thermally injured mice by interfering with NF-kappa B activation and protein expression of ICAM-1, and therefore suppressing the pro-adhesive phenotype of endothelial cells.

[The inhibitory effects of extrinsic carbon monoxide-releasing molecules II on inflammatory responses in liver of mice with severe burns].

OBJECTIVE: To investigate the inhibitory effects of extrinsic carbon monoxide-releasing molecules II on inflammatory responses in liver of mice with severe burns and its potential mechanisms. METHODS: Forty-five male C57BL/6 mice were randomly divided into sham (simulation of burn with 37 degrees C warm water), sham + CORM-2 (with 8 mg/kg CORM-2 after the same manipulation as sham group), burn (with 15% TBSA full-thickness burns), burn + CORM-2 (with 8 mg/kg CORM-2 after the same manipulation as burn group), burn + DMSO (with DMSO after the same treatment as burn group) groups,with 9 mice in each group. The serum level of ALT and AST were determined at 24 post-burn hours (PBH), and the level of myeloperoxidase (MPO), nuclear factor (NF) kappaB, intercellular adhesion molecular (ICAM-1), vascular cell adhesion molecular (VCAM-1), as well as adhesion of polymorphonuclear leucocytes to sinusoidal endothelial cells (HSECs) after serum stimulation were detected and assessed at the same time-points. RESULTS: The level of ALT and AST (398 +/- 34,122 +/- 22 ), the activity of MPO and NF-kappaB, the protein level of ICAM-1 and VCAM-1 in burn group were obviously increased when compared with those in sham group and burn + CORM-2 group (P < 0.05 or P < 0.01). Additionally, the adhesion of PMN on HSEC after stimulation of serum in burn group was enhanced, while it was markedly inhibited after stimulation of serum in burn + CORM-2 group (P < 0.05). CONCLUSION: Extrinsic CORM-2 exhibits the ability to inhibit NF-kappaB activity, reduces the hepatic expression of ICAM-1 and VCAM-1, thereby alleviating sequestration of leukocytes after severe burns, so that hepatic inflammatory response is ameliorated, and liver function is improved.

Attenuation of leukocytes sequestration by carbon monoxide-releasing molecules: liberated carbon monoxide in the liver of thermally injured mice.

We sought to determine whether the CO-releasing molecules, ie, liberated CO, attenuates the leukocytes sequestration in the liver of thermally injured mice. Sixty-five mice were assigned to five groups in three respective experiments. In each experiment, mice in sham group (n = 7) and sham + CORM-2 group (n = 7) were underwent sham thermal injury, whereas mice in burn group (n = 7) received 15% TBSA full-thickness thermal injury, mice in burn + CORM-2 group (n = 7) underwent the same thermal injury with the immediate administration of CORM-2 (8 mg/kg intravenously), and mice in burn + DMSO group (n = 7) underwent the same thermal injury with an immediate 160 microl-bolus injection of 0.5% dimethyl sulfoxide/saline. Polymorphonuclear leucocyte (PMN) accumulation (assessed by the myeloperoxidase assay) was assessed in mice liver. Activation of nuclear factor kappa B (NF-kappaB) and the expression levels of ICAM-1 and VCAM-1 in liver were assessed. In an in vitro experiment, sinusoidal endothelial cells (SECs) isolated from the liver of normal mice were stimulated by experimental mice serum (50% v/v) for 4 hours. Subsequently, the adhesion of PMNs to SECs was assessed. In addition, the number and states (rolling or stationary) of leukocytes in liver were observed by intravital microscopy. Treatment of thermally injured mice with CORM-2 attenuated PMN accumulation and prevented activation of NF-kappaB in the liver, which was accompanied by a decrease of the expression of ICAM-1 and VCAM-1. In parallel, PMNs adhesion to SECs stimulated by CORM-2-treated thermally injured mice serum was markedly decreased. Intravital microscopy showed that the stationary leukocytes in thermally injured mice liver were significantly reduced by treatment of CORM-2. CORM-released CO attenuates leukocytes sequestration in the liver of burn mice by interfering with NF-kappaB activation, protein expression of ICAM-1 and VCAM-1, and therefore suppressing endothelial cells proadhesive phenotype.

Apoptosis and functional changes of dipeptide transporter (PepT1) in the rat small intestine after traumatic brain injury.

BACKGROUND: Traumatic brain injury (TBI) can induce significant alterations of intestinal mucosal structure and barrier function. However, it has not been investigated whether, and to what degree, apoptosis and alterations of absorptive function in the intestinal mucosal epithelium occur after TBI. MATERIAL AND METHODS: Male Wistar rats were randomly divided into seven groups (five rats each group) including normal group, control group with sham operation, and TBI groups at hours 3, 12, 24, and 72, and on day 7. Parietal brain contusion was adopted using weight-dropping method. Intestinal mucosal structure was examined using histomorphmetric study and electron microscopy, and apoptosis was detected by TUNEL method. An everted sleeve of intestine was securely incubated in Kreb's solution with radioactive dipeptide ((3)H-Gly-Sar, 10 microCi/mL) to measure the uptake and transport of PepT1 of small intestinal epithelial cells. RESULTS: The villous height, crypt depth and surface area were significantly decreased at 24 h after TBI, and further declined to the degree of mucosal atrophy on day 7 after TBI. Apoptotic changes of condensed nuclei in epithelial cells and fractured, distorted, and sparse microvilli were found by electron microscopy. The number of apoptotic cells in the mucosal epithelium was significantly increased since 3 h after TBI, peaked at 72 h post-injury, then declined at 7 days, but was still higher than that of control. There was a highly negative relation between the apoptotic index and the villous height, the crypt depth, and villous surface area. Compared with that of normal and control rats, the transport and uptake of dipeptide was significantly increased at 3 h post-injury (P < 0.01), peaked at 12 h and declined a bit at 24 h post-injury, and returned to the level of normal and control rats at 72 h and 7 days. CONCLUSIONS: It is highly suggested that intestinal mucosa apoptosis plays an important role in the pathogenesis of acute gut damage after TBI. Intestinal PepT1 expression could be up-regulated after traumatic brain injury, and maintained the normal level under the condition of serious intestinal damage. Up-regulation of PepT1 may adaptively improve absorption of di- and tripeptides, independent of changes in the mucosal surface area.

[Molecular mechanism of inhibition of early pulmonary injury and inflammatory response by exogenous carbon monoxide: experiment with mice].

OBJECTIVE: To investigate the effect of determine whether the CO-releasing molecules-liberated CO could attenuate leukocytes sequestration and the inflammatory response in the lung of thermally injured mice. METHODS: Thirty-six C57BL/6 mice were randomly divided into 3 groups: burn group, burned with hot water on the back skin with an area as large as 15% of the total body surface area with the hair shed so as o cause full-thickness thermal injury, CORM-2 group, undergoing the same thermal injury and then receiving intravenous injection of CORM-2 immediately, and sham operation group, undergoing sham thermal injury. Twenty-four hours later the mice were killed. The myeloperoxidase enzyme (MPO) level in lung tissue was detected. Evans blue test and lung wet/dry weight ratio were used to examine the lung edema degree. Bronchoalveolar lavage (BAL) fluid was collected to undergo ELISA to detect the tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta. Activation of nuclear factor (NF)-kappaB was detected with electrophoretic mobility shift assay. The expression level of intercellular adhesion molecule-1, ICAM-1) in the lung was assessed by Western blotting. Whole blood samples were collected from the left ventricles. Serum was isolated and used to stimulated lung endothelial cells for 4 h. Polymorphonuclear neutrophilic leukocytes (PMNs) were isolated from mice bone marrow, labeled with Na(51)CrO(4), cultured, and added with the murine lung endothelial cells (MLECs) stimulated by serums from the mice of the 3 groups so as to measure leukocyte adhesion. RESULTS: The MPO activity of the CORM-2 group was (42 +/- 7) U/g tissue, significantly lower than that of the burn group [(87 +/- 11) U/g tissue, P < 0.05]. The Evans blue extraction level of the CORM-1 group was (53.1 +/- 4.6), not significantly different from that of the burn group [(55.1 +/- 3.8), P > 0.05], however, still significantly higher than that of the sham group [(8.8 +/- 1.3), P < 0.05]. The wet/dry weight ratio of the CORM-2 group was 4.80 +/- 0.11, significantly higher than that of the sham group (3.20 +/- 0.07, P < 0.05), but not significantly different from that of the burn group (4.70 +/- 0.18, P > 0.05). The TNF-alpha and IL-1beta levels of the CORM-2 group were (92 +/- 4) pg/ml and (27.2 +/- 2.9) pg/ml respectively, both significantly higher than those of the sham group [(24 +/- 4) pg/ml and (6.6 +/- 1.0) pg/ml respectively, both P < 0.05], but significantly lower that those of the burn group [(160 +/- 9) pg/ml and (27.2 +/- 2.9) pg/ml respectively, both P < 0.05]. The A value for the lung ICAM-1 protein level of the CORM-1 group was (2.4 +/- 0.4), significantly higher than that of the sham group [(1.4 +/- 0.6)], however, significantly lower than that of the burn group [(3.5 +/- 1.1), P < 0.05]. The lung NF-kappaB activity of the CORM-1 group was significantly lower than that of the burn group. The PMN adhesion to the MLECs stimulated by the CORM-2-treated thermally injured mice serum was (25.4 +/- 5.6)%, significantly lower than that of the burn group [(46.5 +/- 8.5)%, P < 0.05]. Also, CORM-2 markedly decreased the production of inflammatory mediators in BAL fluid without suppressing the permeability of pulmonary microcirculation. CONCLUSION: CORM-released CO attenuates the inflammatory response in the lung of thermally injured mice by decreasing leukocyte sequestration and interfering with NF-kappaB activation, protein expression of ICAM-1, thus suppressing endothelial cells pro-adhesive phenotype.