Intestinal damage mediated by Kupffer cells in rats with endotoxemia

Platelet-To-Lymphocyte and Neutrophil-To-Lymphocyte Ratios Predict Intestinal Injury in Male Heroin Addicts

Objective

To explore the potential link between gut damage and proinflammatory cytokines in heroin-dependent patients.

Methods

We retrospectively analyzed and compared partial blood counts and biomarkers of intestinal injury and their potential correlations in 38 male heroin abuse patients and 29 healthy male participants. In addition, we compared and assessed proinflammatory cytokines and immune cells in 10 heroin abuse patients and 10 healthy participants.

Results

Neutrophil counts, platelets/lymphocytes (PLR), neutrophils/lymphocytes (NLR), gut injury biomarkers, and proinflammatory cytokines, CD19+B in patients compared with healthy subjects' cells increased significantly. The number of lymphocytes, CD3 CD4 T cells, and CD3 CD8 T cells decreased in patients compared to healthy individuals. When distinguishing between heroin addicts and healthy people, ROC/AUC analysis showed that a cutoff of 142.42 for PLR and 2.18 for NLR yielded a sensitivity of 65% and 85% and a specificity of 96.5% and 89.7%, respectively (p = 0.001, p < 0.001). For predicting intestinal injury, ROC/AUC analysis showed that a cutoff of 135.7 for PLR and 0.15 for NLR yielded a sensitivity of 52% and 60% and a specificity of 82% and 86.4%, respectively (p = 0.003, p = 0.009). Male heroin addicts are subject to intestinal injury and present with increased proinflammatory cytokine levels.

Conclusion

NLR and PLR are possible indirect biomarkers for heroin dependence based on intestinal injury.

Gadolinium chloride pre-treatment reduces the inflammatory response and preserves intestinal barrier function in a rat model of sepsis

The inflammatory response is closely associated with sepsis occurrence and progression. Damage to the function of the intestinal mucosal barrier is considered to be the ῾initiation factor᾿ for the development of multiple organ dysfunction syndrome, which is the most severe progression of sepsis. The aim of the present study was to investigate whether gadolinium chloride (GdCl₃) could alleviate the systemic inflammatory response and protect the function of the intestinal mucosal barrier in a rat model of sepsis. The mechanism underlying this protective effect was also explored. Sprague-Dawley rats were divided into four groups: Sham, sham + GdCl₃, cecal ligation and puncture (CLP; a model of sepsis) and CLP + GdCl₃. In each group, blood was collected from the abdominal aorta, and intestinal tissue was collected after 6, 12 and 24 h of successful modeling. Levels of tumor necrosis factor-α, interleukin (IL)-6 and IL-1β were determined using ELISA. Western blot analysis was used to determine levels of occludin, tight junction protein ZO-1 (ZO-1), myosin light chain kinase 3 (MLCK), NF-κB and caspase-3 in intestinal tissues. Hematoxylin-eosin staining was used to observe the degree of damage to intestinal tissue. The results indicated that in CLP sepsis model rats treated with GdCl₃, the release of systemic and intestinal pro-inflammatory factors was reduced and tissue damage was alleviated when compared with untreated CLP rats. Additionally, the expression of occludin and ZO-1 was increased, while that of NF-κB, MLCK, and caspase-3 was reduced in the CLP + GdCl₃ rats compared with the CLP rats. GdCl₃ may alleviate systemic and intestinal inflammatory responses and reduce the expression of MLCK through inhibition of the activation of NF-kB. The results of the present study also indicated that GdCl₃ promoted the expression of occludin and ZO-1. GdCl₃ was also demonstrated to reduce cell apoptosis through the inhibition of caspase-3 expression.

Multipotential and systemic effects of traumatic brain injury

Traumatic brain injury (TBI) is one of the leading causes of disability and mortality of people at all ages. Biochemical, cellular and physiological events that occur during primary injury lead to a delayed and long-term secondary damage that can last from hours to years. Secondary brain injury causes tissue damage in the central nervous system and a subsequent strong and rapid inflammatory response that may lead to persistent inflammation. However, this inflammatory response is not limited to the brain. Inflammatory mediators are transferred from damaged brain tissue to the bloodstream and produce a systemic inflammatory response in peripheral organs, including the cardiovascular, pulmonary, gastrointestinal, renal and endocrine systems. Complications of TBI are associated with its multiple and systemic effects that should be considered in the treatment of TBI patients. Therefore, in this review, an attempt was made to examine the systemic effects of TBI in detail. It is hoped that this review will identify the mechanisms of injury and complications of TBI, and open a window for promising treatment in TBI complications.

Nrf2 plays a pivotal role in protection against burn trauma-induced intestinal injury and death

Nuclear factor (erythroid-derived 2)-like 2 (NRF2) is a basic leucine zipper transcription factor that principally defends against oxidative stress and also plays a unique role in severe sepsis. However, its contribution to intestinal injury and death after burn trauma is unclear.In this study, wild-type (Nrf2+/+) and Nrf2-deficient (Nrf2-/-) mice were subjected to 15% or 30% total body surface area burn or sham injury. Survival, systemic inflammation, and gut injury were determined.Nrf2-/- mice were more susceptible to burn-induced intestinal injury, as characterized by increases in damage to the gut structure and in intestinal permeability. This exacerbation was associated with an increase in the intestinal mRNA expression of inflammatory cytokines (interleukin [IL]-6, IL-1B, monocyte chemotactic protein 1, intercellular adhesion molecule, and vascular cell adhesion molecule) and a decrease in the intestinal mRNA expression of Nrf2-regulated genes (NAD(P)H dehydrogenasequinine-1 and glutamate-cysteine ligase modifier subunit). Nrf2-deficient mice also showed a lower survival rate and higher levels of systemic cytokines (IL-6 and IL-1B) and high-mobility group protein B1 than wild-type mice. This study demonstrates for the first time that mice that lack Nrf2 are more susceptible to burn-induced intestinal injury and have more systemic inflammation and a lower survival rate.

Role of programmed death ligand 1 and Kupffer cell in immune regulation after orthotopic liver transplantation in rats

INTRODUCTION

Role of programmed death ligand 1 (PD-L1) and Kupffer cells (KCs) in liver transplantation immune regulation was unclear.

METHODS

Lewis and Brown-Norway (BN) rats were assigned to LEW-BN group (Lewis-to-BN liver transplantation) and BN-BN group (BN-to-BN). Receipts were sacrificed for histology and assessment of cytokines and PD-L1 production. Effect of PD-L1 and KCs on T cells (TCs) was monitored by co-culture of ³H-Thymidine TCs. KCs transfected with PD-L1-shRNA interference plasmids were co-cultured with TCs, PD-L1 expression and cytokines production were measured respectively.

RESULTS

Recipients in BN-BN group survived a long time while acute rejection was found in LEW-BN group. ELISA showed plasma levels of IL-2, IFN-γ and TNF-α in BN-BN group were significantly lower and levels of IL-10 were significantly higher than that in LEW-BN group on day 7 after transplantation (P<0.05). PD-L1 expression of KCs in BN-BN group was significantly higher than that in the LEW-BN group (P<0.05). Proliferation rate of TCs in KCs+TCs group was significantly lower and its apoptosis rate was significantly higher than that in TCs group (P<0.05). IL-2, TNF-α and INF-γ levels were remarkably higher and IL-10 levels were lower in KCs+TCs group than that in TCs group (P<0.05). Levels of IL-2, IFN-γ and TNF-α in transfection group were significantly higher and that of IL-10 was notably lower than that in the un-transfected group (P<0.05).

CONCLUSION

KCs with high expression of PD-L1 could significantly suppress the proliferation and function of TCs. Silencing the expression of PD-L1 in KCs in vivo could restore the function of TCs.

Hepatoprotective effect of ulinastatin in a rat model of major hepatectomy after obstructive jaundice

BACKGROUND

To date, major hepatectomy with obstructive jaundice is still a highly risky and difficult surgery because of the high rate of complications. An excessive inflammatory response may be the primary hindrance to postoperative recovery of liver function.

AIMS

Recent research has demonstrated that ulinastatin blocks the release of inflammatory factors and prevents the cytokine cascade reaction. This study was conducted to investigate the effect of ulinastatin on major hepatectomy after obstructive jaundice and to explore the potential mechanisms of this effect.

METHODS

Male Sprague-Dawley rats were divided into three groups: sham, control and treated groups. In the control and treated groups, obstructive jaundice was induced, and a 70 % major hepatectomy was performed with implementation of ulinastatin treatment in the treated group but not the control group. The rats were sacrificed after hepatectomy on day 1, day 3, day 5 and day 7. The survival time, liver function, inflammatory cytokine expression and the indices of proliferation activities were examined. Kupffer cells were isolated, and the mRNA and protein levels of CD14 and NF-κB P65 in the Kupffer cells were determined.

RESULTS

Compared to the control group, the survival rates, postoperative liver function, and the indices of proliferation activities were better in the treated group; in the treated group serum TNF-α and IL-6 levels were lower whereas serum IL-10 levels were higher. The expression of CD14 and NF-κB P65 in Kupffer cells at both the mRNA and protein levels was significantly higher in the control group than in the treated group.

CONCLUSIONS

Ulinastatin has a protective effect in major hepatectomy with obstructive jaundice by inhibiting Kupffer cell activation and modulating the hepatic cytokine response.

Effects of curcumin on growth performance, jejunal mucosal membrane integrity, morphology and immune status in weaned piglets challenged with enterotoxigenic Escherichia coli

The aim of this study was to evaluate the effect of dietary curcumin supplementation on growth performance and intestinal mucosal barrier function of weaned piglets. Fifty piglets, weaned at 21±2 days of age, were randomly allotted to five treatments for 21 days. The dietary treatments were the control (basal diet), and the basal diet supplemented with 50mg/kg quinocetone, or 200 mg/kg, 300 mg/kg or 400mg/kg curcumin. The piglets were housed in individual pens and orally challenged with enterotoxigenic Escherichia coli (ETEC) during the preliminary trial period. The jejunal morphology and histology analysis were detected under light microscope. The plasma D-lactate and diamine oxidase (DAO) were determined by using enzymatic spectrophotometric assay. Immunohistochemistry assays were used to examine secretory immunoglobulin (sIgA) protein expression. Real-time PCR was used to determine mRNA levels of cytokine and Toll-like receptor 4 (TLR4) in jejunal mucosa. The results showed that, compared with the control, dietary addition of 300 mg/kg or 400 mg/kg curcumin decreased (P<0.05) feed/gain ratio and crypt depth, improved (P<0.05) villus height and villus height:crypt depth ratio, reduced (P<0.05) plasma D-lactate and DAO activity, up-regulated the protein expression of sIgA (P<0.05), increased (P<0.05) the number of goblet cells (GCs) and reduced (P<0.05) the number of intraepithelial lymphocytes (IELs). The mRNA levels of interleukin 1β (IL-1β) and TLR4 and tumor necrosis factor α (TNF-α) were also decreased (P<0.05), but mRNA level of interleukin 10 (IL-10) was increased (P<0.05). There was no difference in the above parameters between the 300 mg/kg and 400 mg/kg curcumin groups. Pigs fed with 50 mg/kg quinocetone also decreased (P<0.05) feed/gain ratio, increased villus height:crypt depth ratio (P<0.05), and reduced (P<0.05) crypt depth and mRNA levels of TLR4. In conclusion, curcumin and the quinocetone have similar effects in improving piglet growth, but dietary addition of 300 mg/kg or 400 mg/kg curcumin was more effective than quinocetone in improving intestinal mucosal barrier integrity, morphology, and immune status of weaned pigs. This indicates that curcumin could be used as a potential feed additive replacing quinocetone in weaned piglets.

Relationship between expression of triggering receptor-1 on myeloid cells in intestinal tissue and intestinal barrier dysfunction in severe acute pancreatitis

BACKGROUND

Triggering receptor expressed on myeloid cells-1 (TREM-1) in the intestine was upregulated and correlated with disease activity in inflammatory bowel diseases. Membrane-bound TREM-1 protein is increased in the pancreas, liver and kidneys of patients with severe acute pancreatitis (SAP), suggesting that TREM-1 may act as an important mediator of inflammation and subsequent extra-pancreatic organ injury. This study aimed to investigate the relationship between the expression of TREM-1 in intestinal tissue and intestinal barrier dysfunction in SAP.

METHODS

Sixty-four male Wistar rats were randomly divided into a sham operation group (SO group, n=32) and a SAP group (n=32). A SAP model was established by retrograde injection of 5% sodium deoxycholate into the bile-pancreatic duct. Specimens were taken from blood and intestinal tissue 2, 6, 12, and 48 hours after operation respectively. The levels of D-lactate, diamine oxidase (DAO) and endotoxin in serum were measured using an improved spectro-photometric method. The expression levels of TREM-1, interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) mRNA in terminal ileum were detected by real-time reverse transcription-polymerase chain reaction (RT-PCR). Specimens of the distal ileum were taken to determine pathological changes by a validated histology score.

RESULTS

The serum levels of D-lactate, DAO and endotoxin were significantly increased in each subgroup of SAP compared with the SO group (P<0.01, P<0.05). The expression levels of TREM-1, IL-1β and TNF-α mRNA in the terminal ileum in each subgroup of SAP were significantly higher than those in the SO group (P<0.01, P<0.05). The expression level of TREM-1mRNA was positively correlated with IL-1β and TNF-α mRNA (r=0.956, P=0.044; r=0.986, P=0.015), but the correlation was not found between IL-1β mRNA and TNF-α mRNA (P=0.133). Compared to the SO group, the pathological changes were aggravated significantly in the SAP group.

CONCLUSIONS

The expression level of TREM-1 in intestinal tissue of rats with SAP was elevated, leading to the release of inflammatory mediators and intestinal mucosal injury. This finding indicates that TREM-l might play an important role in the development of intestinal barrier dysfunction in rats with SAP.

Effect of biliary drainage on inducible nitric oxide synthase, CD14 and TGR5 expression in obstructive jaundice rats

AIM: To investigate the effect of biliary drainage on inducible nitric oxide synthase (iNOS), CD14 and TGR5 expression in rats with obstructive jaundice (OJ).

METHODS: Male adult Sprague-Dawley rats were randomly assigned to four groups: OJ, sham operation (SH), internal biliary drainage (ID) and external biliary drainage (ED). Rat models were successfully established by two operations and succumbed for extraction of Kupffer cells (KCs) and liver tissue collection on the 8^th and 15^th day. KCs were isolated by in situ hepatic perfusion and digested with collagen IV, density gradient centrifuged by percoll reagent and purified by cell culture attachment. The isolated KCs were cultured with the endotoxin lipopolysaccharide (LPS) with and without the addition of ursodeoxycholic acid (UDCA). The expression of iNOS, CD14 and bile acid receptor-TGR5 protein in rat liver tissues was determined by immunohistochemistry. The expression of iNOS and CD14 messenger RNA (mRNA) on the isolated KCs was detected by reverse transcription polymerase chain reaction (PCR) and the TGR5 mRNA level in KCs was measured by real-time quantitative PCR.

RESULTS: The iNOS protein was markedly expressed in the liver of OJ rats, but rare expressed in SH rats. After relief of OJ, the iNOS expression was decidedly suppressed in the ID group (ID vs OJ, P < 0.01), but obviously increased in rats of ED (ED vs OJ, P = 0.004). When interfered only with LPS, the expression of iNOS mRNA by KCs was increased in the OJ group compared with the SH group (P = 0.004). After relief of biliary obstruction, the iNOS mRNA expression showed slight changes in the ED group (ED vs OJ, P = 0.71), but dropped in the ID group (ID vs OJ, P = 0.001). Compared with the simple intervention with LPS, the expressions of iNOS mRNA were significantly inhibited in all four groups after interfered with both LPS and UDCA (P < 0.01, respectively). After bile duct ligation, the CD14 protein expression in rat liver was significantly strengthened (OJ vs SH, P < 0.01), but the CD14 mRNA level by KCs was not up-regulated (OJ vs SH, P = 0.822). After relieving the OJ, the expression of CD14 protein was reduced in the ID group (ID vs OJ, P < 0.01), but not reduced in ED group (ED vs OJ, P = 0.591). And then the CD14 mRNA expression was aggravated by ED (ED vs OJ, P < 0.01), but was not significantly different between the ID group and the SH and OJ groups (ID vs SH, P = 0.944; ID vs OJ, P = 0.513, respectively). The expression of TGR5 protein and mRNA increased significantly in OJ rats (OJ vs SH, P = 0.001, respectively). After relief of OJ, ID could reduce the expression of TGR5 protein and mRNA to the levels of SH group (ID vs SH, P = 0.22 and P = 0.354, respectively), but ED could not (ED vs SH, P = 0.001, respectively).

CONCLUSION: ID could be attributed to the regulatory function of activation of KCs and release of inflammatory mediators.

The role of CD14 and Toll-like receptor 4 of Kupffer cells in hepatic ischemia-reperfusion injury in rats

OBJECTIVE

The objective of this study was to study the role of CD14 and Toll-like receptor 4 (TLR4) in Kupffer cells (KCs) on ischemia reperfusion injury (IRI) in rat liver grafts.

METHODS

Isolated KCs were obtained from control, IRI, and IRI plus anti-CD14 antibody groups. We measured messenger RNA (mRNA) and protein expression of the lipopolysaccharide receptor CD14 and TLR4, nuclear factor kappa B (NF-κβ) activity, and TNF-α levels.

RESULTS

mRNA and protein expressions of CD14 and TLR4 were significantly higher in the IRI than in the control group, as were protein expressions of CD14 and TLR4 by flow cytometry and by Western blots. NF-κβ activity and tumor necrosis factor-α level in the IRI group were significantly higher than in the control group (3.17 ± 0.21 and 0.28 ± 0.03 vs 654.2 ± 3.6 pg/mL and 147.4 ± 1.1 pg/mL; t value = 4.11 and 4.29 for each; P < .01). Compared with the IRI group they were greatly decreased after anti-CD14 antibody treatment: 2.14 ± 0.17 vs 3.17 ± 0.21, 298.7 ± 1.8 pg/mL vs 654.2 ± 3.6 pg/mL (t value = 2.52 and 2.92 for each; P < .05). They were still significantly higher than the control group (t values of 3.01 and 3.27 for each; P < .01).

CONCLUSION

IRI up-regulated CD14 and TLR4 gene expression in KCs, and subsequently activated NF-κβ to produce cytokines.

TREM-1 Promotes Pancreatitis-Associated Intestinal Barrier Dysfunction

Severe acute pancreatitis (SAP) can cause intestinal barrier dysfunction (IBD), which significantly increases the disease severity and risk of mortality. We hypothesized that the innate immunity- and inflammatory-related protein-triggering receptor expressed on myeloid cells-1 (TREM-1) contributes to this complication of SAP. Thus, we investigated the effect of TREM-1 pathway modulation on a rat model of pancreatitis-associated IBD. In this study we sought to clarify the role of TREM-1 in the pathophysiology of intestinal barrier dysfunction in SAP. Specifically, we evaluated levels of serum TREM-1 and membrane-bound TREM-1 in the intestine and pancreas from an animal model of experimentally induced SAP. TREM-1 pathway blockade by LP17 treatment may suppress pancreatitis-associated IBD and ameliorate the damage to the intestinal mucosa barrier.

Suppression of nuclear factor-kappaB activity in Kupffer cells protects rat liver graft from ischemia-reperfusion injury

OBJECTIVE

The objective of this study was to investigate the protective effect and mechanisms of nuclear factor (NF)-kappaB decoy oligodeoxynucleotides (ODN) on rat liver grafts following ischemia-reperfusion injury (IRI).

METHODS

Animals were randomly divided into 3 groups (n = 8): control ischemia-reperfusion (IR) and decoy ODN groups; in the last cohort donor grafts were transfected with 120 microg NF-kappaB decoy ODN before procurement. Following 2 hours of reperfusion, NF-kappaB binding activity was detected in isolated Kupffer cells (KCs) using electrophoretic mobility shift assays (EMSA). Tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 messenger RNA (mRNA) expressions were analyzed using reverse transcriptase polymerase chain reaction (RT-PCR) methods. Liver tissue and blood serum were collected for histopathologic examination and liver function test, respectively.

RESULTS

The NF-kappaB binding activity, TNF-alpha and IL-6 mRNA expression as well as serum ALT and total bilirubin levels were significantly increased compared with the control group following reperfusion (P < .01). A large number of hepatocytes showed degeneration and necrosis. However, these indices were significantly ameliorated among the decoy ODN group (P < .01) with preserved hepatic lobule architecture.

CONCLUSION

KCs NF-kappaB activation following reperfusion plays an important role in IRI after liver transplantation. The decoy strategy showed an apparent effect to suppress NF-kappaB activation and inhibit production of downstream cytokines, thereby protecting liver grafts from IRI.

Curcumin protects intestinal mucosal barrier function of rat enteritis via activation of MKP-1 and attenuation of p38 and NF-κB activation

Background

Intestinal mucosa barrier (IMB) dysfunction results in many notorious diseases for which there are currently few effective treatments. We studied curcumin's protective effect on IMB and examined its mechanism by using methotrexate (MTX) induced rat enteritis model and lipopolysaccharide (LPS) treated cell death model.

Methodology/Principal Findings

Curcumin was intragastrically administrated from the first day, models were made for 7 days. Cells were treated with curcumin for 30 min before exposure to LPS. Rat intestinal mucosa was collected for evaluation of pathological changes. We detected the activities of D-lactate and diamine oxidase (DAO) according to previous research and measured the levels of myeloperoxidase (MPO) and superoxide dismutase (SOD) by colorimetric method. Intercellular adhesion molecule-1 (ICAM-1), tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β) were determined by RT-PCR and IL-10 production was determined by ELISA. We found Curcumin decreased the levels of D-lactate, DAO, MPO, ICAM-1, IL-1β and TNF-α, but increased the levels of IL-10 and SOD in rat models. We further confirmed mitogen-activated protein kinase phosphatase-1 (MKP-1) was activated but phospho-p38 was inhibited by curcumin by western blot assay. Finally, NF-κB translocation was monitored by immunofluorescent staining. We showed that curcumin repressed I-κB and interfered with the translocation of NF-κB into nucleus.

Conclusions/Significance

The effect of curcumin is mediated by the MKP-1-dependent inactivation of p38 and inhibition of NF-κB-mediated transcription. Curcumin, with anti-inflammatory and anti-oxidant activities may be used as an effective reagent for protecting intestinal mucosa barrier and other related intestinal diseases.

[Effects of Quyu Jiedu Granule on expressions of tumor necrosis factor-alpha and interleukin-6 mRNAs in ovarian granulosa cells of endometriosis rats]

OBJECTIVE

To observe the effects of Quyu Jiedu Granule, a compound traditional Chinese herbal medicine for removing blood stasis and expelling superficial evils, on the quality of oocytes and the expressions of tumor necrosis factor-alpha (TNF-alpha)and interleukin-6 (IL-6) mRNAs in ovarian granulosa cells of endometriosis (EM) rats.

METHODS

Forty EM rats were randomly divided into two groups: experimental group and control group. There were 20 EM rats in each group. The uteri of another 20 SD rats were drawn in sham-operated group. The number and percentage of high quality oocytes and the levels of TNF-alpha and IL-6 mRNA expressions in the granulosa cells of EM rats were detected by using reverse transcription-polymerase chain reaction.

RESULTS

The number and percentage of high quality oocytes in the experimental group were significantly higher than those in the control group (P<0.05), and the levels of TNF-alpha and IL-6 mRNAs in granulose cells in the experimental group were significantly lower than those in the control group (P<0.05).

CONCLUSION

The increase of the TNF-alpha and IL-6 mRNA expressions in ovarian granulose cells of EM rats leads to the decrease of the oocyte quality. The mechanism of Quyu Jiedu Granule in improving the quality of oocytes may be related to the decrease of TNF-alpha and IL-6 mRNA expressions in ovarian granulosa cells.

Changing patterns of serum and bile antibodies in re-infected rats with Clonorchis sinensis

Rats develop strong resistance to re-infection and super-infection by Clonorchis sinensis. The present study investigated the antibodies present in the sera and bile juice of rats that were primary infected and re-infected with C. sinensis. The serum level of specific IgG antibodies, which were elevated 2 wk of the primary infection, peaked at 4 wk and subsequently remained unchanged even during re-infection. The total IgE level in serum increased slowly from 388 ng / ml to 3,426 ng / ml beginning 2 wk after the primary infection, and remained high up to 8 wk but dropped to a normal level (259 ng / ml) after treatment. In resistant re-infected rats, the serum IgE level increased rapidly and peaked within 1 wk, whereas no increase was observed in immunosuppressed rats. The serum level of specific IgA antibodies was elevated beginning 1 wk after infection, and decreased 4 wk after treatment. The total bile IgA level unchanged during the primary infection but increased in treated and re-infected rats. The elevated levels of serum IgE and bile IgA indicate that these immunoglobulins may be correlated with the development of resistance to re-infection by C. sinensis in rats.

Increased intestinal inflammatory response and gut barrier dysfunction in Nrf2-deficient mice after traumatic brain injury

AIM

To explore the role of nuclear factor erythroid 2-related factor 2 (Nrf2) in traumatic brain injury (TBI)-induced intestinal inflammatory response and gut barrier dysfunction in the mice.

METHODS

Wild-type Nrf2 (+/+) and Nrf2 (-/-)-deficient mice were subjected to a moderately severe weight-drop impact-acceleration head injury. We measured nuclear factor kappa B (NF-kappaB) by electrophoretic mobility shift assay (EMSA); tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) by enzyme-linked immunosorbent assay (ELISA); intercellular adhesion molecule-1 (ICAM-1) by immunohistochemistry; intestinal permeability by lactulose/mannitol (L/M) test; plasma endotoxin by chromogenic limulus amebocyte lysate test.

RESULTS

Intestinal levels of NF-kappaB, pro-inflammatory cytokines and ICAM-1 in Nrf2 (-/-)-deficient mice were significantly higher compared with Nrf2 (+/+) mice at 24h after TBI. Furthermore, higher intestinal permeability and plasma level of endotoxin were observed in the Nrf2 (-/-) mice compared with Nrf2 (+/+) mice.

CONCLUSION

Nrf2 plays an important protective role in limiting intestinal inflammatory response and gut barrier dysfunction after TBI.

Role of Kupffer cells in the induction of tolerance of orthotopic liver transplantation in rats

Because the role of Kupffer cells (KCs) in liver transplantation (LT) tolerance is not well understood, we investigated their role in liver allograft acceptance in rats. Male Sprague-Dawley rats were randomly assigned to either an LT group or a transplantation group pretreated with GdCl(3) (Gd group). The rats were postoperatively sacrificed at indicated times for histology and assessment of KC function, nuclear factor kappa B (NF-kappaB) activity, and cytokine production. KCs and T cells (TCs) were isolated from allografts to assess Fas/Fas ligand (FasL) expression. Cytotoxicity of KCs against TCs was monitored by coculturing of (3)H-thymidine TCs with KCs at various effector-to-target ratios. The results were as follows. First, grafts were spontaneously accepted in the LT group with evident apoptosis of TCs; however, inhibition of KCs by pretreatment with GdCl(3) decreased TC apoptosis and shortened the survival of allografts. Second, KCs in the LT group had increased levels of FasL messenger RNA and protein with respect to that in the Gd group. Third, by in vitro cocultivation assays, KCs induced TC apoptosis though elevated expression of FasL, and this process could be blocked by anti-FasL antibody. Fourth, there was a positive correlation between activation of NF-kappaB and FasL expression in KCs and interleukin-4 production in the LT group, and the activation of NF-kappaB was inhibited by pretreatment with GdCl(3). In conclusion, KC-induced depletion of TCs via the Fas/FasL pathway might play a critical role in LT tolerance. However, the tolerance is abrogated by suppression of FasL and IL-4 expression via inhibition of NF-kappaB activity by GdCl(3).

Isolation of Kupffer cells and their suppressive effects on T lymphocyte growth in rat orthotopic liver transplantation

AIM: To develop a practical method for isolation, purification and culture of hepatic Kupffer cells (KCs) and to observe their suppressive effects on the proliferation of alloreactive T cells.

METHODS: Perfusion in situ in vivo combined with density gradient centrifugation was applied in isolation, purification and culture of hepatic KC. The suppression by KCs on the T cell proliferation in mixed lymphocyte reaction (MLR) was observed.

RESULTS: This method resulted in a satisfactorily high yield of (1.1 ± 0.2) × 10⁷ KCs per liver, (93.5% ± 1.8%) viable cells, over 90% purity and positive for ED-2. After the first 24 h in culture, a great number of KCs which exhibited typical characteristics were observed. Using ³H-TdR incorporation assay, non-irradiated KCs significantly suppressed allo-MLR. The KCs recovered from accepted liver allografts in groups D and E were more effective in suppressing allo-MLR.

CONCLUSION: A standardized procedure for isolation of highly purified rat KCs is proposed and KCs have suppressive effects on the proliferation of alloreactive T cells, especially those derived from accepted liver allografts.

Intralysosomal accumulation of gadolinium and lysosomal damage during selective depression of liver macrophages in vivo

Kinetics of gadolinium accumulation was studied by inductively coupled plasma-emission spectroscopy after intravenous injection of this agent (7.5 mg/kg) to CBA mice. Gadolinium exhibits lysosomotropic properties (long-term selective accumulation in lysosomes in vivo). Gadolinium uptake by hepatic cells attained maximum 1 h after its intravenous injection and remained at this level during the next day. Accumulation of gadolinium in hepatocytic lysosomes disturbed their osmotic properties (as was seen from the increase in free acid phosphatase activity, which persisted for 19 days). Serum activities of beta-D-galactosidase and beta-D-glucuronidase also increased (24-72 h and day 19). Selective depression of liver macrophages (24-48 h) was accompanied by a decrease in serum chitotriosidase activity. We conclude that accumulation of gadolinium in lysosomes of liver macrophages leads to their damage and elimination of a certain population of macrophages (primarily large cells). Changes in activity of serum lysosomal enzymes also reflect repopulation of liver macrophages.

Effect of chronic ethanol administration on the in vitro production of proinflammatory cytokines by rat Kupffer cells in the presence of apoptotic cells

BACKGROUND

Chronic ethanol consumption can lead to a variety of pathological consequences by as yet undefined mechanisms. Recently, it has been noted that alcohol-associated liver disease is often accompanied by morphological liver changes that include the increased production of apoptotic cells. Additionally, it has been demonstrated that hepatocellular uptake and removal of potentially damaging apoptotic cells is impaired after ethanol treatment. The aim of the present study was to determine whether the presence of apoptotic cells leads to Kupffer cell (KC) production and release of proinflammatory cytokines that have been linked to hepatocyte damage, such as interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-alpha).

METHODS

Kupffer cells were isolated from female rats after an 8-week oral administration of a dextrose control or ethanol-containing fish-oil diet. The isolated KCs were cultured for up to 24 hours in the absence or presence of apoptotic or nonapoptotic hepatoma cells, or lipopolysaccharide. After incubation, media from the cultures were assayed for the presence of TNF-alpha and IL-6 by immunoassay detection. Also, the expression of these cytokines was measured in KC lysates by a quantitative real-time polymerase chain reaction.

RESULTS

Kupffer cells cultured for up to 24 hours in the presence of apoptotic cells produced significantly more TNF-alpha and IL-6 (80 and 60%, respectively, p<0.05) when the cells were isolated from ethanol-fed animals compared with controls. Additionally, after as early as 4 hours in culture with apoptotic cells, mRNA levels of both cytokines were increased (2-5-fold) in KCs isolated from ethanol-fed animals compared with controls.

CONCLUSIONS

The presence of apoptotic cells results in the in vitro activation of KCs. Additionally, chronic ethanol administration results in an enhanced responsiveness of KCs to produce proinflammatory cytokines indicated by the increased production of inflammatory mediators from KCs obtained from ethanol-fed animals.

Association between portal endotoxemia and Child-Pugh classification in complex pathogens-induced hepatic cirrhosis in rats

AIM: To evaluate the association between the Child-Pugh classification and portal endotoxe-mia during the course of rat liver cirrhosis induced by carbon tetrachloride (CCl₄) plus ethanol and cholesterol.

METHODS: Liver cirrhosis model was induced in 20 Wistar rats using CCl₄ plus ethanol and cholesterol, while 6 rats were treated as controls. At 6 and 10 wk, serum samples were collected from portal vein for the detection of prothrombin time, albumin, bilirubin and endotoxin level, and the ascites and brain wave were also tested. The liver function was evaluated by Child-Pugh scoring system and the relationship between Child-Pugh classification and portal endotoxemia was assessed.

RESULTS: Spearman rank correlation analysis showed that Child-Pugh grading was correlated with albumin level and prothrombin time (r = -0.695, P < 0.05; r = 0.649, P < 0.05), but not with bilirubin level (P > 0.05). The level of endotoxin in portal vein was elevated with prolonging of cirrhosis time, and it was significantly higher at 6 or 10 wk than that in the controls (1983.7 ± 586.4, 2600.7 ± 343.8 mEU/L vs 925.1 ± 527.7 mEU/L, both P < 0.01). Endotoxin level was correlated with cirrhosis time (r = 0.624, P < 0.01) and Child-Pugh classification (r = 0.680, P < 0.01).

CONCLUSION: Portal endotoxemia is significantly correlated with Child-Pugh classification, indicating that intestinal endotoxemia plays an important role during the course of complex pathogens-induced cirrhosis in rats.

Expressions of intestinal NF-kappaB, TNF-alpha, and IL-6 following traumatic brain injury in rats

BACKGROUND

NF-kappaB regulates a large number of genes involved in the inflammatory response to critical illness, but it is not well known if and how NF-kappaB is activated in the gut following traumatic brain injury (TBI) and what is the role of cytokine-mediated inflammation in the pathogenesis of acute gut mucosal injury.

MATERIALS AND METHODS

Male Wistar rats were randomly divided into control and TBI groups, each of which was subgrouped at hours 3, 12, 24, and 72 and on day 7. Parietal brain contusion was produced by a free-falling weight on the exposed dura of the right parietal lobe. NF-kappaB binding activity in jejunal tissue was measured using EMSA and the concentrations of TNF-alpha and IL-6 were detected using ELISA.

RESULTS

NF-kappaB binding activity in the jejunum was significantly increased at 3 h following TBI, was maximal at 72 h, and remained elevated by 7 days postinjury. TNF-alpha and IL-6 concentrations were also significantly increased by 3 h postinjury, but peaked at 24 h and remained elevated on Day 7 postinjury.

CONCLUSIONS

TBI induced a rapid and persistent up-regulation of NF-kappaB and proinflammatory cytokines in the gut, which may play an important role in the pathogenesis of acute gut mucosal injury mediated by inflammation.

Involvement of mast cells in basal and neurotensin-induced intestinal absorption of taurocholate in rats

Neurotensin (NT), a hormone released from intestine by ingested fat, facilitates lipid digestion by stimulating pancreatic secretion and slowing the movement of chyme. In addition, NT can contract the gall bladder and enhance the enterohepatic circulation (EHC) of bile acids to promote micelle formation. Our recent finding that NT enhanced and an NT antagonist inhibited [(3)H]taurocholate ([(3)H]TC) absorption from proximal rat small intestine indicated a role for endogenous NT in the regulation of EHC. Here, we postulate the involvement of intestinal mast cells in the TC uptake process and in the stimulatory effect of NT. In anesthetized rats with the bile duct cannulated for bile collection, infusion of NT (10 pmol.kg(-1).min(-1)) enhanced the [(3)H]TC recovery rate from duodenojejunum by 2.2-fold. This response was abolished by pretreatment with mast cell stabilizers (cromoglycate, doxantrazole) and inhibitors of mast cell mediators (diphenhydramine, metergoline, zileuton). In contrast, mast cell degranulators (compound 48/80, substance P) and mast cell mediators (histamine, leukotriene C(4)) reproduced the effect of NT. N(G)-nitro-l-arginine methyl ester enhanced and l-arginine inhibited basal and NT-induced TC uptake, consistent with the known inhibitory effect of nitric oxide (NO) on mast cell reactivity. These results argue that basal and NT-stimulated TC uptake in rat jejunum are similarly dependent on mast cells, are largely mediated by release of mast cell mediators, and are subject to regulation by NO.

CD14 expression in Kupffer cells of ischemia-reperfusion injury after rat liver transplantation

AIM: To study the expression of lipopolysaccharide receptor CD14 mRNA and protein in Kupffer cells and its role in ischemia-reperfusion injury (IRI) in rat liver graft.

METHODS: The Kupffer cells were isolated and divided into control, ischemia-reperfusion (IR), and anti CD14 antibody groups. The CD14 mRNA, CD14 protein, nuclear factor kappa B (NF-κB) activity, and TNF-α and IL-1 level in the culture supernatant were measured.

RESULTS: The CD14 mRNA, and protein in IR group were significantly higher than those in control group (mRNA 1.28±0.12 vs 0.42±0.02, protein 23.7±2.36 vs 6.3±1.27, P < 0.01). The NF-κB activity, TNF-α and IL-1 level in IR group were significantly higher than those in control group (NF-κB 2.79±0.48 vs 0.27±0.01, TNF-α 205.9±12.04 ng/L vs 57.4±4.35 ng/L, IL-1 176.8±8.94 ng/L vs 37.6±3.47 ng/L, P < 0.01), and they greatly decreased after anti-CD14 antibody treatment compared with IR group (NF-κB 1.34±0.24 vs 2.79±0.48, TNF-α 129.6±6.48 ng/L vs 205.9±12.04 ng/L, IL-1 103.4±5.74 ng/L vs 176.8±8.94 ng/L, P < 0.05), but still significantly higher than those in control group (NF-κB 1.34±0.24 vs 0.27±0.01, TNF-α 129.6±6.48 ng/L vs 57.4±4.35 ng/L, IL-1 103.4±5.74 ng/L vs 37.6±3.47 ng/L, P < 0.01).

CONCLUSION: LPS following IR can up-regulate the expression of CD14 mRNA and protein in Kupffer cells, and subsequently activate NF-κB to produce cytokines. But other signal transduction pathways might also participate in the NF-κB activation and IRI.

Alterations of intestinal mucosa structure and barrier function following traumatic brain injury in rats

AIM: Gastrointestinal dysfunction is a common complication in patients with traumatic brain injury (TBI). However, the effect of traumatic brain injury on intestinal mucosa has not been studied previously. The aim of the current study was to explore the alterations of intestinal mucosa morphology and barrier function, and to determine how rapidly the impairment of gut barrier function occurs and how long it persists following traumatic brain injury.

METHODS: Male Wistar rats were randomly divided into six groups (6 rats each group) including controls without brain injury and traumatic brain injury groups at hours 3, 12, 24, and 72, and on day 7. The intestinal mucosa structure was detected by histopathological examination and electron microscopy. Gut barrier dysfunction was evaluated by detecting serum endotoxin and intestinal permeability. The level of serum endotoxin and intestinal permeability was measured by using chromogenic limulus amebocyte lysate and lactulose/mannitol (L/M) ratio, respectively.

RESULTS: After traumatic brain injury, the histopathological alterations of gut mucosa occurred rapidly as early as 3 hours and progressed to a serious state, including shedding of epithelial cells, fracture of villi, focal ulcer, fusion of adjacent villi, dilation of central chyle duct, mucosal atrophy, and vascular dilation, congestion and edema in the villous interstitium and lamina propria. Apoptosis of epithelial cells, fracture and sparseness of microvilli, loss of tight junction between enterocytes, damage of mitochondria and endoplasm, were found by electron microscopy. The villous height, crypt depth and surface area in jejunum decreased progressively with the time of brain injury. As compared with that of control group (183.7 ± 41.8 EU/L), serum endotoxin level was significantly increased at 3, 12, and 24 hours following TBI (434.8 ± 54.9 EU/L, 324.2 ± 61.7 EU/L and 303.3 ± 60.2 EU/L, respectively), and peaked at 72 hours (560.5 ± 76.2 EU/L), then declined on day 7 (306.7 ± 62.4 EU/L, P < 0.01). Two peaks of serum endotoxin level were found at hours 3 and 72 following TBI. L/M ratio was also significantly higher in TBI groups than that in control group (control, 0.0172 ± 0.0009; 12 h, 0.0303 ± 0.0013; 24 h, 0.0354 ± 0.0025; 72 h, 0.0736 ± 0.0105; 7 d, 0.0588 ± 0.0083; P < 0.01).

CONCLUSION: Traumatic brain injury can induce significant damages of gut structure and impairment of barrier function which occur rapidly as early as 3 hours following brain injury and lasts for more than 7 days with marked mucosal atrophy.

The mRNA expression patterns of tumor necrosis factor-α and TNFR-I in some vital organs after thermal injury

AIM: To investigate changes of tumor necrosis factor-α (TNF-α) and TNFR-I expression in vital organs and their significance in the pathogenesis of multiple organ damage associated with endogenous endotoxin following major burns.

METHODS: Wistar rats subjected to a 35% full-thickness scald injury were sacrificed at 12 h, 24 h, 48 h, and 72 h postburn, respectively. Meanwhile, eight rats were taken as normal controls. Tissue samples from liver, spleen, kidney, lung and intestine were collected to assay tissue endotoxin levels and measure TNF-α and TNFR-I expression. In addition, blood samples were obtained for the determination of organ function parameters.

RESULTS: Endotoxin levels in liver, spleen and lung increased markedly after thermal injury, with the highest level in liver. The gene expression of TNF-α in liver, lung and kidney was up-regulated after thermal injury, while the TNFR-I mRNA expression in liver, lung, kidney and intestine was shown decreased throughout the observation period. Thus, the mRNA expression ratio of TNF-α to TNFR-I was significantly increased postburn, particularly in pulmonary tissue (67-fold). In addition, the significant correlations between the expression of TNFR-I or the expression ratio of TNF-α/TNFR mRNA in liver tissue and serum aspartate aminotransferase levels were noted (P < 0.05-0.01). Similar results were also obtained between pulmonary TNF-α mRNA expression and myeloperoxidase activities (P < 0.01), whereas there was a highly negative correlation between levels of renal TNFR-I mRNA expression and serum creatinine.

CONCLUSION: Burn injury could result in the translocation of gut-derived endotoxin that was mainly distributed in the liver, spleen and lung. The translocated endotoxin then made the expression of TNF-α and TNFR-I mRNA up-regulated and down-regulated respectively in various organs, which might be involved in the pathogenesis of multiple organ damage following burns.

TNF-α expression and effects of Dachengqi Decoctionin compound in gut macrophages

AIM

To explore the rule of producing TNF-a in gut macrophages through respects of gene expression and protein synthesis of TNF α and to observe the effect of dexamethasone (DEX), monocolonal antibody to tumor necrosis factor alpha (TNF α moAb) and Fufang Dachengqi Decoction compound on TNF α production.

METHODS

The cultured rat gut macrophages were divided into five groups: control group (group C), lipopolysaccharide (LPS) group (group L), DEX treated group (group L+D), TNF α-MoAb treated group (group L+M), LPS plus Fufang Da Chengqi Decoction treated group (group L+F). Each group was divided into four phases: cultured for 3, 6, 12, and 24 h. The supernatants were collected and frozen at -70℃ until TNF α was determined, and the cells were used to isolate the RNA. TNF α levels were determined by radioimmunoassay method. The expression of TNF α mRNA was evaluated by RT-PCR.

RESULTS

The level of TNFα and expression of TNFα mRNA significantly increased at each phase in group L.The level of TNFα significantly decreased at each phase in group L+D, group L+M and group L+F compared with group L. The expression of TNFα mRNA in each treatment group had no obvious difference, compared with group L in 3 h, but group L+D and group L+F significantly decreased in 6, 12, and 24h. Group L+M still showed no obvious difference.

CONCLUSION

Gut macrophage induced by LPS can produce more TNFα through its gene expression and protein synthesis. DEX, Fufang Dachengqi Decoction can suppress the TNFα mRNA transcription and protein synthesis of TNF α; TNFα -moAb only lowered the level of TNFα protein. The three drugs have protective effects in inflammatory mediators reaction, gut barrier damage and multiple organ dysfunction syndrome (MODS).

Synthesis of endotoxin receptor CD14 protein in Kupffer cells and its role in alcohol-induced liver disease

AIM: To observe the synthesis of endotoxin receptor CD14 protein and its mRNA expression in Kupffer cells (KCs), and evaluate the role of CD14 in the pathogenesis of liver injury in rats with alcohol-induced liver disease (ALD).

METHODS: Twenty-eight Wistar rats were divided into two groups: ethanol-fed group and control group. Ethanol-fed group was fed ethanol (dose of 5-12g·kg·d^-1) and control group received dextrose instead of ethanol. Two groups were sacrificed at 4 wk and 8 wk, respectively. KCs were isolated and the synthesis of CD14 protein and its mRNA expression in KCs were determined by flow cytometric analysis (FCM) or the reverse transcription polymerase chain reaction (RT-PCR) analysis. The levels of plasma endotoxin and alanine transaminase (ALT) were measured by Limulus Amebocyte Lysate assay and standard enzymatic procedures respectively, and the levels of plasma tumor necosis factor (TNF)-α and interleukin (IL)-6 were both determined by ELISA. The liver pathology change was observed under light and electric microscopy.

RESULTS: In ethanol-fed group, the percentages of FITC-CD14 positive cells were 76.23% and 89.42% at 4 wk and 8 wk, respectively. Compared with control group (4.45% and 5.38%), the difference was significant (P < 0.05). The expressions of CD14 mRNA were 7.56 ± 1.02 and 8.74 ± 1.37 at 4 wk and 8 wk, respectively, which were significantly higher compared with the control group (1.77 ± 0.21 and 1.98 ± 0.23) (P < 0.05). Plasma endotoxin levels at 4 wk and 8 wk increased significantly in ethanol-fed group (129 ± 21 ng·L^-1 and 187 ± 35 ng·L^-1) than those in control rats (48 ± 9 ng·L^-1 and 53 ± 11 ng·L^-1)(P < 0.05). Mean values of plasma ALT levels increased dramatically in ethanol-fed rats (112 ± 15 IU/L and 147 ± 22 IU/L) than those in the control animals (31 ± 12 IU/L and 33 ± 9 IU/L) (P < 0.05). In ethanol-fed rats, the levels of TNF-α were 326 ± 42 ng·L^-1 and 402 ± 51 ng·l^-1 at 4 wk and 8 wk, respectively which were significantly higher than those in control group (86 ± 12 ng·L^-1 and 97 ± 13 ng·L^-1) (P < 0.05). The levels of IL-6 were 387 ± 46 ng·L^{- 1} and 413 ± 51 ng·L^-1, which were also higher than control group (78 ± 11 ng·L^-1 and 73 ± 10 ng·L^-1) (P < 0.05). In liver section from ethanol-fed rats, there were marked pathological changes including steatosis, cell infiltration and necrosis. No marked pathological changes were seen in control group.

CONCLUSION: Ethanol administration led to a significant synthesis of endotoxin receptor CD14 protein and its gene expression in KCs, which maybe result in the pathological changes of liver tissue and hepatic functional damages.

Role of NF-κB in multiple organ dysfunction during acute obstructive cholangitis

AIM: To elucidate the role of NF-κB activation in the development of multiple organ dysfunction (MOD) during acute obstructive cholangitis (AOC) in rats.

METHODS: Forty-two Wistar rats were divided into three groups: the AOC group, the group of bile duct ligation (BDL group), and the sham operation group (SO group). All the animals in the three groups were killed in the 6th and 48th hour after operation. Morphological changes of vital organs were observed under light and electron microscopy. NF-κB activation was determined with Electrophoretic Mobility Shift Assay (EMSA). Arterial blood gas analyses and the serum levels of lactate dehydrogenase (LDH), alanine aminotransferase (ALT), blood urea nitrogen (BUN) and creatinine were performed. The concentrations of TNF-α and IL-6 in plasma were also measured.

RESULTS: The significant changes of histology and ultrastructure of vital organs were observed in AOC group. By contrast, in BDL group, all the features of organs damage were greatly reduced. Expression of NF-κB activation in various tissues increased in AOC group when compared to other two groups. At 6 h, the arterial pH in three groups was 7.52 ± 0.01, 7.46 ± 0.02, and 7.45 ± 0.02, and the blood pCO₂ was 33.9 ± 0.95 mmHg, 38.1 ± 0.89 mmHg, 38.9 ± 0.94 mmHg, there was difference in three groups (P < 0.05). At 48 h, the blood pHvalues in three groups was 7.33 ± 0.07, 7.67 ± 0.04, and 7.46 ± 0.03, and blood HCO₃^- was 20.1 ± 1.29 mmol·L^-1, 26.7 ± 1.45 mmol·L^-1 and 27.4 ± 0.35 mmol·L^-1, there was also difference in three groups (P < 0.05). In AOC group, Levels of LDH, ALT, BUN and creatinine were 16359.9 ± 2278.8 nkat·L^-1, 5796.2 ± 941.9 nkat·L^-1, 55.7 ± 15.3 mg/dl, and 0.72 ± 0.06 mg/dl, which were higher than in SO group (3739.1 ± 570.1 nkat·L^-1, 288.4 ± 71.7 nkat·L^-1, 12.5 ± 2.14 mg/dl, and 0.47 ± 0.03 mg/dl) (P < 0.05). Levels of plasma TNF-α and IL-6 in AOC at 48 h were 429 ± 56.62 ng·L^-1 and 562 ± 57 ng·L^-1, which increased greatly when compared to BDL group (139 ± 16 ng·L^-1, 227 ± 43 ng·L^-1) and SO group (74 ± 10 ng·L^-1, 113 ± 19 ng·L^-1) (P < 0.05).

CONCLUSION: The pathological damages and the NF-κB activation of many vital organs exised during AOC. These findings have an important implication for the role of NF-κB activation in MOD during AOC.

Effects of recombinant human growth hormone on rat septic shock with intraabdominal infection by E. coli

AIM: To investigate the therapeutic effects of recombinant human growth hormone (rhGH) on rat septic shock with intraabdominal infection by E. coli and its possible mechanism.

METHODS: 76 SD rats were divided into 3 groups randomly: control group (group C, n = 16) without any special treatment, septic shock group (group S, n = 30) received bolus injection of E.coli (1 × 10¹⁰ cfu·L^-1,15 mL·kg^-1, ip), treated group (group T, n = 30) received bolus injection of E.coli, and then followed by rhGH injection (2.25 U·kg^-1·d^-1, im). Group S and group T were further divided into 1d and 3d subgroups, respectively (n = 15 each). Mean arterial pressure (MAP), levels of plasma TNFα and endotoxin and leukocyte count were determined on 1st day and 3rd day after E.coli injection. Another 39 SD rats were divided into groups C, S and T (n = 13 each) just for observing survival rate within 1 week.

RESULTS: (1) On 1st and 3rd day, MAP in group S decreased markedly, and MAP on 1st day lowered more than that of 3rd day (P < 0.01), while MAP in group T just decreased slightly. The survival rate within 1 week was much higher in group T (84.6%) than in group S (46.2%) (P < 0.01). (2)On 1st day, plasma TNFα and endotoxin elevated significantly in group S and group T (P < 0.05), and endotoxin in group S had more increase (P < 0.01). On 3rd day, TNFα in group S returned to the level of group C (P > 0.05),while TNFα in group T went down below the level of group C(P < 0.01). On 3rd day, endotoxin in group S declined, but was still higher than that of group C (P < 0.01), endotoxin in group T returned to the level of group C (P > 0.05). (3) On 1st day, neutrophil ratio in total leukocyte count in both group S and group T increased significantly (P < 0.05 vs group C).

CONCLUSION: rhGH showed beneficial effects on rat septic shock. The possible mechanisms may involve the attenuation of bacteria/endotoxin translocation and decreased systemic endotoxin level; inhibition of the production and release of TNFα; improved circulatory function; improved systemic host defenses and maintenance of intestinal mucosa barrier.

Expression of CD14 protein and its gene in liver sinusoidal endothelial cells during endotoxemia

AIM: To observe expression of CD14 protein and CD14 gene in rat liver sinusoidal endothelial cells (LSECs) during endotoxemia, and the role of CD14 protein in the activation of lipopolysaccharide (LPS)-induced LSECs.

METHODS: Wistar rat endotoxemia model was established first by injection of a dose of LPS (5 mg/kg, Escherichia coli O111:B4) via the tail vein, then sacrificed after 0 h, 3 h, 6 h, 12 h, and 24 h, respectively. LSECs were isolated from normal and LPS-injected rats by an in situ collagenase perfusion technique. The isolated LSECs were incubated with rabbit anti-rat CD14 polyclonal antibody, then stained with goat anti rabbit IgG conjugated fluorescein isothiocyanate (FITC) and flow cytometric analysis (FCM) was performed. The percentage and mean fluorescence intensity (MFI) of CD14-positive cells were taken as the indexes. LSECs were collected to measure the expression of CD14 mRNA by in situ hybridization analysis. The isolated LSECs from normal rats were incubated firstly with anti-CD14 antibody, then stimulated with different concentrations of LPS, and the supernatants of these cells were then collected for measuring the levels of tumor necrosis factor (TNF)-α and Interleukin (IL)-6 with ELISA.

RESULTS: In rats with endotoxemia, LSECs displayed a strong MFI distinct from that of control rats. CD14 positive cells in rats with endotoxemia were 54.32%, 65.83%, 85.64%, and 45.65% at 3 h, 6 h, 12 h, and 24 h respectively, there was significant difference when compared to normal group of animals (4.45%) (P < 0.01). The expression of CD14 mRNA in isolated LSECs was stronger than that in control rats. In LPS group, the levels of TNF-α and IL-6 were 54 ± 6 ng·L^-1, 85 ± 9 ng·L^-1, 206 ± 22 ng·L^-1, 350 ± 41 ng·L^-1, 366 ± 42 ng. L^-1 and 103 ± 11 ng·L^-1, 187 ± 20 ng·L^-1, 244 ± 26 ng·L^-1, 290 ± 31 ng·L^-1, and 299 ± 34 ng·L^-1, respectively at different concentration points. In anti-CD14 group, the levels of TNF-α and IL-6 were 56 ± 5 ng·L^-1, 67 ± 8 ng·L^-1, 85 ± 10 ng·L^-1, 113 ± 12 ng·L^-1, 199 ± 22 ng·L^-1 and 104 ± 12 ng·L^-1, 125 ± 12 ng·L^-1, 165 ± 19 ng·L^-1, 185 ± 21 ng·L^-1, and 222 ± 23 ng·L^-1, respectively at different concentration points. There was significant difference between the two groups (P < 0.01).

CONCLUSION: LSECs can synthesize CD14 protein and express CD14 gene during endotoxemia. CD14 protein plays an important role in the activation of LPS-induced LSECs. This finding has important implications for the understanding of the mechanisms by which LPS may injure liver sinusoidal endothelial cells during sepsis.

Liver sinusoidal endothelial cell injury by neutrophils in rats with acute obstructive cholangitis

AIM: The objective of this study is to elucidate the potential role of poly-morphonuclear neutrophils (PMN) in the development of such a sinusoidal endothelial cell (SEC) injury during early acute obstructive cholangitis (AOC) in rats.

METHODS: Twenty one Wistar rats were divided into three groups: the AOC group, the bile duct ligated group (BDL group), and the sham operation group (SO group). The common bile duct (CBD) of rats in AOC group was dually ligated and 0.2 mL of the E. coli O₁₁₁ B₄ (5 × 10⁹ cfu/mL) suspension was injected into the upper segment, in BDL group, only the CBD was ligated and in SO group, neither injection of E. coli suspension nor CBD ligation was done, but the same operative procedure. Such group consisted of seven rats, all animals were killed 6 h after the operation. Morphological changes of the liver were observed under light and electron microscope. Expression of intercellular adhesion molecule-1 (ICAM-1) mRNA in hepatic tissue was determined with reverse transcription polymerase chain reaction (RT-PCR). The serum levels of alanine aminotransferase (ALT) were determined with anutoanalyger and cytokine-induced neutrophil chemoattractant (CINC) was determined by enzyme-linked immunosorbent assay (ELISA).

RESULTS: Neutrophils was accumulated in the hepatic sinusoids and sinusoidal endothelial cell injury existed in AOC group. In contrast, in rats of BDL group, all the features of SEC damage were greatly reduced. Expression of ICAM-1 mRNA in hepatic tissue in three groups were 7.54 ± 0.82, 2.87 ± 0.34, and 1.01 ± 0.12, respectively. There were significant differences among three groups (P < 0.05). The serum CINC levels in the three groups were 188 ± 21 ng•L⁻¹, 94 ± 11 ng•L⁻¹, and 57 ± 8 ng•L⁻¹, respectively. There were also significant differences among the three groups (P < 0.05). Activity of the serum ALT was 917 ± 167 nkat•L⁻¹, 901 ± 171 nkat•L⁻¹, and 908 ± 164 nkat•L⁻¹, respectively, (P > 0.05).

CONCLUSION: Hepatic SEC injury occurs earlier than hepatic parenchymal cells during AOC. Recruitments of circulating neutrophils in the hepatic sinusoidal space might mediate the SEC injury, and ICAM-1 in the liver may modulate the PMN of accumulation.