Liqun Tang

Xuebijing injection alleviates liver injury by inhibiting secretory function of Kupffer cells in heat stroke rats

OBJECTIVEnTo evaluate the effects of Xuebijing (XBJ) injection in heat stroke (HS) rats and to investigate the mechanisms underlying these effects.nnnMETHODSnSixty anesthetized rats were randomized into three groups and intravenously injected twice daily for 3 days with 4 mL XBJ (XBJ group) or phosphate buffered saine (HS and Sham groups) per kg body weight. HS was initiated in the HS and XBJ groups by placing rats in a simulated climate chamber (ambient temperature 400C, humidity 60% ). Rectal temperature, aterial pressure, and heart rate were monitored and recorded. Time to HS onset and survival were determined, and serum concentrations of tumor necrosis factor (TNF)-alpha interleukin (IL)-1beta, IL-6, alanine-aminotransferase (ALT), and aspartate-aminotransferase (AST) were measured. Hepatic tissue was harvested for pathological examination and electron microscopic examination. Kupffer cells (KCs) were separated from liver at HS initiation, and the concentrations of secreted TNF-a, IL-beta and IL-6 were measured.nnnRESULTSnTime to HS onset and survival were significantly longer in the XBJ than in the HS group. Moreover, the concentrations of TNF-alpha, IL-1beta, IL-6, ALT and AST were lower and liver injury was milder in the XBJ than in the HS group. Heat-stress induced structural changes in KCs and hepatic cells were more severe in the HS than in the XBJ group and the concentrations of TNF-alpha, IL-beta and IL-6 secreted by KCs were lower in the XBJ than in the HS group.nnnCONCLUSIONnXBJ can alleviate HS-induced systemic inflammatory response syndrome and liver injury in rats, and improve outcomes. These protective effects may be due to the ability of XBJ to inhibit cytokine secretion by KCs.

Eicosapentaenoic Acid Enhances Heat Stress-Impaired Intestinal Epithelial Barrier Function in Caco-2 Cells

Objective Dysfunction of the intestinal epithelial tight junction (TJ) barrier is known to have an important etiologic role in the pathophysiology of heat stroke. N-3 polyunsaturated fatty acids (PUFAs), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), play a role in maintaining and protecting the TJ structure and function. This study is aimed at investigating whether n-3 PUFAs could alleviate heat stress-induced dysfunction of intestinal tight junction. Methods Human intestinal epithelial Caco-2 cells were pre-incubated with EPA, DHA or arachidonic acid (AA) and then exposed to heat stress. Transepithelial electrical resistance (TEER) and Horseradish Peroxidase (HRP) permeability were measured to analyze barrier integrity. Levels of TJ proteins, including occludin, ZO-1 and claudin-2, were analyzed by Western blot and localized by immunofluorescence microscopy. Messenger RNA levels were determined by quantitative real time polymerase chain reaction (Q-PCR). TJ morphology was observed by transmission electron microscopy. Results EPA effectively attenuated the decrease in TEER and impairment of intestinal permeability in HRP flux induced by heat exposure. EPA significantly elevated the expression of occludin and ZO-1, while DHA was less effective and AA was not at all effective. The distortion and redistribution of TJ proteins, and disruption of morphology were also effectively prevented by pretreatment with EPA. Conclusion This study indicates for the first time that EPA is more potent than DHA in protecting against heat-induced permeability dysfunction and epithelial barrier damage of tight junction.

HMGB1 activity inhibition alleviating liver injury in heatstroke.

BACKGROUND Heatstroke is generally considered as a sepsis-like syndrome induced by hyperthermia leading to multiorgan dysfunction. High-mobility group box 1 (HMGB1) has recently been identified as a mediator of systemic inflammation leading to multiorgan dysfunction in sepsis and nonsepsis. Elevation of plasma HMGB1 in heatstroke has been suggested in experimental models and clinical patients. By far, whether HMGB1 could be a potential therapeutic target in heatstroke is unknown. The objectives of this study are to use HMGB1 monoclonal antibody to specifically inhibit the activity of extracellular HMGB1 and to observe the possible protection of liver injury in a rat heatstroke model. METHODS After treatment with neutralizing antibodies to HMGB1, rats were exposed to a high-temperature and high-humidity environment. At the time of heatstroke onset, the plasma and liver cytoplasm HMGB1 levels were detected by enzyme-linked immunosorbent assay. The histopathology of liver tissue was observed under light microscopy and transmission electron microscopy. Plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were determined using the commercially available kits. Plasma tumor necrosis factor-&agr;, interleukin-1&bgr; (IL-1&bgr;), and IL-6 were determined using enzyme-linked immunosorbent assay kits. RESULTS HMGB1 levels in plasma and liver cytoplasm were both elevated in heatstroke rats, which were both associated with increased plasma ALT and AST levels. Histopathologic results showed that HMGB1 monoclonal antibody pretreatment could obviously alleviate the pathologic impairments of heatstroke rats. HMGB1 monoclonal antibody pretreatment could also downregulate plasma AST and ALT levels in heatstroke rats. Plasma tumor necrosis factor-&agr;, IL-1&bgr;, and IL-6 levels in heatstroke rats were elevated, which could be significantly suppressed by HMGB1 antibody pretreatment. CONCLUSION HMGB1 could be a potentially effective treatment target in heatstroke. The pathogenic mechanism of heatstoke is complicated, which needs comprehensive prevention and treatment.

Ten-year retrospective analysis of multiple trauma complicated by pulmonary contusion.

BackgroundThis study reports a 10-year retrospective analysis of multiple trauma complicated by pulmonary contusion. The purpose of this study is to ascertain the risk factors for mortality due to trauma in patients with pulmonary contusion, the impact of various treatment options for prognosis, and the risk factors for concurrent Acute Respiratory Distress Syndrome (ARDS).MethodsWe retrospectively analyzed 252 trauma patients with lung contusion admitted to the General Hospital of Guangzhou Command from January 2000 to June 2011 by using the statistical processing system SPSS 17.0 for Windows.ResultsWe included 252 patients in our study, including 214 males and 38 females. The average age was 37.1u2009±u200914.9xa0years. There were 110 cases admitted to the ICU, of which 26 cases with ARDS. Nine of the 252 patients died. We compared those who survived with those who died by gender and age, the difference was not statistically significant (Pu2009=u20090.199, Pu2009=u20090.200). Separate univariate analysis of those who died and those who survived found that shock on admission (Pu2009=u20090.000), coagulation disorders (Pu2009=u20090.000), gastrointestinal bleeding (Pu2009=u20090.02), the need for emergency surgery on admission (Pu2009=u20090.000), pre-hospital intubation (Pu2009=u20090.000), blood transfusion within 24xa0hours (Pu2009=u20090.006), the use of mechanical ventilation (Pu2009=u20090.000), and concurrent ARDS (Pu2009=u20090.000) are poor prognosis risk factors. Further logistic analysis, including the admission GCS score (ORu2009=u20090.708, 95% CI 0.516-0.971, Pu2009=u20090.032), ISS score (OR 1.135, 95% CI 1.006-1.280, Pu2009=u20090.039), and concurrent ARDS (ORu2009=u200915.814, 95% CI 1.819-137.480, Pu2009=u20090.012), identified the GCS score, ISS score and concurrent ARDS as independent risk factors of poor prognosis. Shock (ORu2009=u20099.121, 95% CI 0.857-97.060, Pu2009=u20090.067) was also related to poor prognosis. Patients with injury factors such as road accident, falling injury, blunt injury and crush injury, et al.(Pu2009=u20090.039), infection (Pu2009=u20090.005), shock (Pu2009=u20090.004), coagulation disorders (Pu2009=u20090.006), emergency surgery (Pu2009=u20090.01), pre-hospital intubation (Pu2009=u20090.000), chest tube insertion (Pu2009=u20090.004), blood transfusion (Pu2009=u20090.000), usage of hormones (Pu2009=u20090.002), phlegm (Pu2009=u20090.000), ventilation (Pu2009=u20090.000) were at a significantly increased risk for ARDS complications.ConclusionsThose patients with multiple trauma and pulmonary contusion admitted to the hospital with shock, coagulopathy, a need for emergency surgery, pre-hospital intubation, and a need for mechanical ventilation could have a significantly increased risk of mortality and ARDS incidence. A risk for poor prognosis was associated with gastrointestinal bleeding. A high ISS score, high APACHE2, and low GCS score were independent risk factors for poor prognosis. If patients developed an infection or were given drainage, hormones, and phlegm treatment, they were at higher risk of ARDS. Pre-hospital intubation and drainage were independent risk factors for ARDS. In patients with ARDS, the ICU stay, total length of stay, and hospital costs might increase significantly. A GCS scoreu2009<u20095.5, APACHE 2 scoreu2009>u200916.5, and ISS scoreu2009>u200920.5 could be considered indicators of poor prognosis for patients with multiple trauma and lung contusion.

Vascular Endothelial Cell Injury Partly Induced by Mesenteric Lymph in Heat Stroke

Animal models have shown that mesenteric lymph plays important roles in the pathogenesis of endothelium injury in many critical ill states. Gut-derived septicemia and endothelium injury are the two key pathogenesis of heat stroke (HS); however, it is unclear whether mesenteric lymph is cytotoxic to endothelium in HS. HS rat models were prepared in a prewarmed incubator. Mesenteric lymph, collected pre-, during, and post-HS, was analyzed for biological activity on human umbilical vein endothelial cell (HUVEC) in vitro. The effect of HS lymph on the production of von Willebrand factor (vWF), thrombomodulin (TM), and IL-6 by HUVEC was investigated. In vivo, vascular endothelium injury biomarkers, circulating endothelial cell (CEC), as well as serum soluble vWF and TM were tested in rats of HS and HS with mesenteric lymph duct ligation (HS-LDL). HS but not heat stroke sham mesenteric lymph-injured endothelial cells showed significantly increased HUVEC cytotoxicity and enhanced HUVEC monolayer permeability as well as elevated levels of vWF and TM production by HUVEC. IL-6 production by HUVEC was augmented by HS lymph in vitro. The effects of HS lymph on IL-6 production had a time course resembling that of the toxic effects of HS lymph on HUVEC. In vivo, when compared with HS rats, decreased CEC counts as well as lower serum vWF and TM concentrations were detected in HS-LDL rats. HS mesenteric lymph is probably harmful to vascular endothelium, which indicates that the modulation of mesenteric lymph may have some potential benefits to HS.

Xuebijing attenuates hypotension through the upregulation of angiotensin II type 1 receptor‑associated protein 1 in rats suffering from heat stroke

In our previous study, we demonstrated that Xuebijing (XBJ), a traditional Chinese medicine, attenuates hypotension in rats suffering from heatstroke (HS). However, the underlying mechanisms have not yet been fully elucidated. Thus, the current study was carried out to investigate the mechanisms underlying the effects of XBJ on hypotension n rats suffering from HS. For this purpose, 72 anesthetized rats were randomized into 3 groups and intravenously injected twice daily for 3 days with XBJ (4 ml/kg body weight, XBJ group) or phosphate‑buffered saline (PBS) (HS and sham-operated groups). Models of HS were established in the HS and XBJ groups by placing the rats in a simulated climate chamber with a temperature of 40˚C and a humidity of 60%. Rectal temperature, arterial pressure and heart rate were monitored and recorded. Angiotensin Ⅱ (Ang Ⅱ) levels were increased during HS (shown by ELISA), and XBJ had no apparent effect on Ang Ⅱ levels. The levels of Ang Ⅱ type 1 (AT1) receptor surface expression and AT1 receptor-associated protein 1 (Arap1) were decreased during HS; however, these effects were attenuated by pre-treatment with XBJ (shown by RT-qPCR and western blot analysis). For in vitro experiments, rat macrophages pre-treated with XBJ were stimulated with lipopolysaccharide (LPS). Pre-treatment with XBJ induced a marked inhibitory effect on the release of pro-inflammatory cytokines in the LPS-stimulated macrophages. Furthermore, XBJ inhibited the activation of nuclear factor κB (NF-κB) induced by LPS in the macrophages. Taken together, our data demonstrate that XBJ promotes Arap1 expression by inhibiting the activation of the NF-κB signaling pathway and the release of pro-inflammatory cytokines, which may be the molecular mechanisms through which XBJ alleviates blood pressure reduction in rats suffering from HS.

The liver sinusoidal endothelial cell damage in rats caused by heatstroke

This study was designed to explore whether liver sinusoidal endothelial cells (SECs) play a pathological role in liver injury of heatstroke (HS) in rats. An HS rat model was prepared in a pre-warmed incubator. Rats were randomized into four groups: HS-sham group (SHAM group), the 39°C group, the 42°C group, and the HS group. The serum concentrations of SEC injury biomarkers including hyaluronic acid (HA), von Willebrand factor (vWF), thrombomodulin (TM), were measured. Plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities and endothelium-derived vasoactive substances including endothelin-1 (ET-1) and nitric oxide (NO) were determined using a commercially available kit. Hepatic tissues were obtained for histopathological examination, electron microscopy examination, immunohistochemistry, and reverse transcription polymerase chain reaction (PCR) analysis. Our study team found increased levels of plasma ALT/AST during the course of HS. We were also able to detect microcirculation changes and inflammatory injury of the liver (especially in the sinusoidal areas). In addition, markers of SEC injury were significantly elevated. Thrombosis-related markers including vWF and TF expression levels were significantly upregulated and TM levels downregulated. Furthermore, imbalance between ET-1 and NO levels were detected. In conclusion, damage of SECs could result in microcirculation disturbances and pro-inflammatory injury in the liver during HS, which could prove to be a potential pathogenic mechanism of liver injury in HS.