Inhibition of diethylnitrosamine-initiated alcohol-promoted hepatic inflammation and precancerous lesions by flavonoid luteolin is associated with increased sirtuin 1 activity in mice

Background

Chronic and excessive alcohol consumption is an established risk for hepatic inflammation and carcinogenesis. Luteolin is one of the most common flavonoids present in plants and has potential beneficial effects against cancer. In this study, we examined the effect and potential mechanisms of luteolin supplementation in a carcinogen initiated alcohol-promoted pre-neoplastic liver lesion mouse model.

Methods

C57BL/6 mice were injected with diethylnitrosamine (DEN) [i.p. 25 mg/kg of body weight (BW)] at 14 days of age. At 8 weeks of age mice were group pair-fed with Lieber-DeCarli liquid control diet or alcoholic diet [ethanol (EtOH) diet, 27% total energy from ethanol] and supplemented with a dose of 30 mg luteolin/kg BW per day for 21 days.

Results

DEN-injected mice fed EtOH diet displayed a significant induction of pre-neoplastic lesions, a marker associated with presence of steatosis and inflammation. Dietary luteolin significantly reduced the severity and incidence of hepatic inflammatory foci and steatosis in DEN-injected mice fed EtOH diet, as well the presence of preneoplastic lesions. There was no difference on hepatic protein levels of sirtuin 1 (SIRT1) among all groups; however, luteolin supplementation significantly reversed alcohol-reduced SIRT1 activity assessed by the ratio of acetylated and total forkhead box protein O1 (FoXO1) and SIRT1 target proliferator-activated receptor gamma, coactivator 1 alpha (PGC1α).

Conclusions

Dietary intake of luteolin prevents alcohol promoted pre-neoplastic lesions, potentially mediated by SIRT1 signaling pathway.     

Effect of chronic alcohol consumption on the development and progression of non-alcoholic fatty liver disease (NAFLD)

A number of epidemiologic studies show a protective effect of light to moderate daily alcohol consumption on the development of non-alcoholic fatty liver disease (NAFLD). Although these small amounts of ethanol may prevent fatty liver, they may also be a risk factor for other diseases such as breast and colon cancer. Those individuals who have underlying hepatic steatosis or non-alcoholic steatohepatitis (NASH) should not use ethanol chronically since the data available at present do not support a beneficial effect of alcohol in this situation. Especially overweight and obese individuals may be more susceptible towards alcohol even at moderate doses. Animal experiments show a negative effect of ethanol on liver histology in either dietary or genetic NASH models. In addition, patients with NASH reveal a significant increased risk for hepatocellular cancer (HCC) even with social alcohol consumption. Thus, subjects with underlying NASH should abstain from alcohol at any amounts.     

Liver tissue microbiota in nonalcoholic liver disease: a change in the paradigm of host-bacterial interactions

Nonalcoholic fatty liver disease (NAFLD) pathogenesis is explained by the complex relationship among diet and lifestyle-predisposing factors, the genetic variance of the nuclear and mitochondrial genome, associated phenotypic traits, and the yet not fully explored interactions with epigenetic and other environmental factors, including the microbiome. Despite the wealth of knowledge gained from molecular and genome-wide investigations in patients with NAFLD, the precise mechanisms that explain the variability of the histological phenotypes are not fully understood. Earlier studies of the gut microbiota in patients with NAFLD and nonalcoholic steatohepatitis (NASH) provided clues on the role of the fecal microbiome in the disease pathogenesis. Nevertheless, the composition of the gut microbiota does not fully explain tissue-specific mechanisms associated with the degree of disease severity, including liver inflammation, ballooning of hepatocytes, and fibrosis. The liver acts as a key filtration system of the whole body by receiving blood from the hepatic artery and the portal vein. Therefore, not only microbes would become entrapped in the complex liver anatomy but, more importantly, bacterial derived products that are likely to be potentially powerful stimuli for initiating the inflammatory response. Hence, the study of liver tissue microbiota offers the opportunity of changing the paradigm of host-NAFLD-microbial interactions from a “gut-centric” to a “liver-centric” approach. Here, we highlight the evidence on the role of liver tissue bacterial DNA in the biology of NAFLD and NASH. Besides, we provide evidence of metagenomic findings that can serve as the seed of further hypothesis-raising studies as well as can be leveraged to discover novel therapeutic targets.     

Exploration the potential mechanism of the SIRT1 and its target gene FOXO1/PPARGC1A in uteropelvic junction obstruction

BackgroundUteropelvic junction obstruction (UPJO) is a common surgical condition, which refers to the blockage of urine flowing through kidney into proximal upper ureter. However, the underlying mechanism of UPJO is poorly understood, especially the regulated and targeted genes of sirtuin 1 in UPJO.MethodsWe sequenced three renal tissues on the obstructed side of independent children with <20% differential renal function (DRF) and three samples with >40% DRF. Gene expression values were obtained and compared for differentially expressed genes (DEGs). Protein-protein interaction (PPI) analysis was conducted to identify the overlapping proteins of DEGs and Sirtuin 1 (SIRT1). The co-expression genes of overlapped genes were computed using Pearson correlation coefficient. The potential role of SIRT1 gene in UPJO was explored by resequencing 3 microarray data from RNA interference (RNAi) SIRT1 lines of renal tubular epithelial (NRK52E) cells in rat and three control datasets were sequenced again. The DEGs were obtained as parallel. GO/KEGG enrichment analysis and co-expression network were conducted to explore the underlying mechanism, particularly shared pathways or function in GO/KEGG enrichment analysis results.ResultsA total of 427 up-regulated genes and 1,099 down-regulated genes were identified among 3 mRNA-seq of renal tissue on the obstructed side of the independent children with <20% DRF and 3 samples with >40% DRF. According to prediction using the Search Tool for Retrieval of Interacting Genes/Proteins, 2 PPIs, FOXO1 and PPARGC1A, were identified among 2,524 DEGs, predicted as targets of SIRT1. Gene set enrichment analysis (GSEA) of their co-expression genes showed they may co-participate in biological activities including fatty acid degradation, regulation of signal transduction by p53 mediator. Moreover, GSEA results of DEGs was confirmed through RNAi SIRT1 lines of rat renal tubular epithelial (NRK52E) cells.ConclusionsUPJO may cause abnormal phenotypic changes of renal tubular epithelial cells through SIRT1/FOXO1 mediated protein transport, establishment of protein localization, and intracellular transport. In addition, UPJO is involved in regulation of signal transduction, regulation of intracellular estrogen receptor signaling pathways, and nucleoprotein localization through SIRT1/PPARGC1A-mediated p53 mediators, causing abnormal phenotypic changes in renal tubular epithelial cells.     

Expression of Eya1 and Six1 is decreased in distal airways of rats with experimental pulmonary hypoplasia

Background/Purpose

Pulmonary hypoplasia (PH) associated with congenital diaphragmatic hernia (CDH) represents one of the major challenges in neonatal intensive care. Eyes absent 1 (Eya1) and sine oculis homebox 1 (Six1) have been identified as essential components of the gene network that regulates foetal lung development. Eya1 and Six1 are expressed in distal epithelial tips of branching airways as well as in surrounding mesenchymal cells, highlighting their important role during branching morphogenesis. Lungs of Eya1^−/− and Six1^−/− knockouts display PH with reduced epithelial branching, appearing to be arrested in the pseudoglandular stage. We hypothesized that Eya1 and Six1 expression is decreased in branching airways of nitrofen-induced PH.

Methods

Time-mated rats received either nitrofen or vehicle on E9.5. Foetal lungs were dissected on E15.5 and divided into control and nitrofen groups, whereas lungs harvested on E18.5 were divided into controls, PH without CDH [PH(−)], and PH with CDH [PH(+)]. Pulmonary gene expression levels of Eya1 and Six1 were analyzed by quantitative real-time PCR. Immunofluorescence staining was performed to investigate Eya1 and Six1 protein expression and localization by confocal laser scanning microscopy (CLSM).

Results

Relative mRNA expression of Eya1 and Six1 was significantly decreased in PH(−) and PH(+) on E18.5 compared to controls. CLSM confirmed markedly diminished immunofluorescence of Eya1 and Six1 in distal airway epithelium as well as in surrounding mesenchymal cells of nitrofen-induced PH on E18.5 compared to controls.

Conclusions

Downregulation of Eya1 and Six1 gene expression in nitrofen-induced PH suggests that decreased Eya1 and Six1 expression during the late pseudoglandular stage may interfere with epithelial branching and distal airway maturation, thus resulting in PH.     

Detection of carcinogenic etheno-DNA adducts in children and adolescents with non-alcoholic steatohepatitis (NASH)

Background

Carcinogenic exocyclic-DNA adducts like 1,N⁶-etheno-2''-deoxyadenosine (εdA) are formed through reactive intermediates of 4-hydroxynonenal (4-HNE) or other lipid peroxidation (LPO) products with the DNA bases A, C, methyl-C and G. High levels of hepatic etheno-DNA adducts have been detected in cancer prone liver diseases including alcoholic liver disease (ALD). In ALD εdA levels correlated significantly with cytochrome P-450 2E1 (CYP2E1) expression which is also induced in non-alcoholic steatohepatitis (NASH). We investigated the occurrence of εdA adducts in children with NASH as a DNA damage marker.

Methods

Liver biopsies from 21 children/adolescents with histologically proven NASH were analysed for hepatic fat content, inflammation, and fibrosis. εdA levels in DNA, CYP2E1-expression and protein bound 4-hydroxynonenal (HNE) were semi-quantitatively evaluated by immunohistochemistry.

Results

Among 21 NASH children, εdA levels in the liver were high in 3, moderate in 5, weak in 9 and not elevated in 4 patients. There was a positive correlation between CYP2E1 and protein-bound 4-HNE (r=0.60; P=0.008) and a trend for a positive relationship for CYP2E1 vs. staining intensity of εdA (r=0.45; P=0.06). Inflammatory activity and fibrosis correlated significantly (r=0.49, P=0.023).

Conclusions

Our results demonstrate for the first time the presence of elevated carcinogenic etheno-DNA lesions (εdA) in the majority (17/21) of liver biopsies from young NASH patients. Our data suggest that LPO-derived etheno-adducts are implicated in NASH. Whether these adducts may serve as predictive risk markers in NASH children to develop hepatocellular cancer later in life remains to be investigated.     

Effect of decreased physical activity on bone mass in exercise-trained young rats

 The aim of this study was to determine whether decreased physical activity in exercise-trained young rats would result in a lower rate of bone gain or a reversal of the benefits of exercise. Thirty-five female Wistar rats, 6 weeks of age, were randomized into seven groups: 7 weeks of exercise (7EX), 7 weeks of sedentary control (7CN), 11 weeks of exercise (11EX), 7 weeks of exercise followed by 4 weeks of exercise cessation (7EX4C), 7 weeks of exercise followed by 4 weeks of decreased exercise frequency (7EX4F), 7 weeks of exercise followed by 4 weeks of decreased exercise intensity (7EX4I), and 11 weeks of sedentary control (11CN). The running intensity (speed) and duration were 25 m/min for 60 min/day at a frequency of 5 days/week. During the last 4 weeks, exercise frequency was reduced to 1 day/week in the 11EX4F group, and exercise intensity (speed) was reduced to 12 m/min in the 7EX4I group. After each period of exercise, the bone mineral content (BMC) of the proximal, middle, and distal tibiae, determined by dual-energy X-ray absorptiometry (DXA), was significantly greater in the 7EX and 11EX groups than in the 7CN and 11CN groups, respectively, but it was significantly lower in the 7EX4C group than in the 11EX group and did not differ significantly from the values of the 11CN group. Although the BMC of the proximal and middle tibiae did not differ significantly among the 7EX4F, 7EX4I, 7EX4C, and 11CN groups, the BMC of the distal tibia was significantly greater in the 7EX4F and 7EX4I groups than in the 11CN group and tended to be greater than in the 7EX4C group. The results of this study suggest that the effect of decreased exercise intensity and frequency on bone mass appears to be site specific in the tibia of the exercise-trained young rats. This study shows that exercise-trained young rats lose the benefits gained from exercise when exercise is completely ceased, resulting in the reduction of bone mass to levels that do not differ significantly from those of sedentary controls. At least, continuous exercise appears to be necessary for the maintenance of high bone mass. Received: June 5, 2001 / Accepted: January 7, 2002     

An interleukin 1 activity produced by peritoneal macrophages is increased with accelerated bone resorption in ovariectomized adult rats

Interleukin 1 (IL-1) is known to stimulate bone resorptionin vitro and appears to influence the bone remodeling. Recently spontaneous release of IL-1 from blood monocytes was found to reflect bone formation in idiopathic osteoporosis. Since we developed the radiogrammetrical longitudinal method to quantitate the dynamic bone resorption rate in ovariectomized adult rats, the author has studied the relationship between bone resorption and IL-1 production by cultured peritoneal macrophages from adult rats. Endosteal bone resorption rate was accelerated in ovariectomized adult rate compared with sham-operated rats from 4 to 11 weeks after operations, as judged by radiogrammetrical longitudinal study of the tibial cortex. Peritoneal macrophages from ovariectomized adult rats produced more IL-1 activity than sham-operated rats 6 weeks after operations. These results suggest that dynamic index of bone resorption was higher in ovariectomized adult rats with increased IL-1 activity. Thus, IL-1 may be responsible, at least in part, for the postovariectomy accelelation in bone resorption.     

Amelioration of intestinal reperfusion injury by moderate hypothermia is associated with serum sICAM-1 levels

BACKGROUND: The aim of this study was to investigate the effects of moderate hypothermia on various serum markers involving in inflammation after intestinal ischemia-reperfusion (IR). MATERIALS AND METHODS: The model of 30 min intestinal ischemia +90 min reperfusion was used. Three groups of rats were studied, n=7-8 per group: 1) sham at normothermia, 36.5 to 37.5 degrees C; 2) IR at normothermia and; 3) IR at moderate hypothermia, 32 to 33 degrees C. Serum levels of TNF-alpha, lipopolysaccharide-inducible CXC chemokine (LIX), and soluble intercellular adhesion molecule-1 (sICAM-1) were determined using ELISA technique. Histological features of terminal ileum were also graded. RESULTS: Intestinal IR at normothermia caused remarkable tissue injury together with an elevation in serum TNF-alpha, LIX, and sICAM-1 levels. Moderate hypothermia significantly decreased the degree of mucosal damage and attenuated the elevation of serum sICAM-1 levels. However, there were no significant differences in serum TNF-alpha and LIX levels between IR at normothermia and IR at hypothermia. CONCLUSIONS: Intestinal IR at normothermia induces the elevation of serum TNF-alpha, LIX, and sICAM-1 levels. Moderate hypothermia protects the small intestine from reperfusion injury. This beneficial effect is associated with serum sICAM-1 levels but not with serum TNF-alpha and LIX levels. We speculate that one of the mechanisms, by which hypothermia blunts the tissue injury, is at the step of firm adhesion between leukocytes and endothelial cells.     

Atherosclerosis is associated with plasminogen activator inhibitor type-1 in chronic haemodialysis patients

Aim: The aim of the present report was to investigate the probable association of circulating levels of PAI-1 and expression of PAI-1 in internal iliac artery walls with atherosclerotic disease in chronic haemodialysis (HD) patients. Methods: Sixty-eight non-diabetic HD patients and 50 age- and sex-matched healthy normotensive controls participated in the study. Atherosclerotic disease in both groups was assessed by measuring intima-media thickness (IMT) and plaque score of the common carotid arteries using an ultrasound scanner. Levels of serum PAI-1, C-reactive protein (CRP), interleukin (IL)-6 and lipids profile were measured. Internal iliac artery samples were obtained at the time of renal transplantation. Quantitative expression of PAI-1 in internal iliac artery walls was assessed by positive unit (pu) value using an immunohistochemical method. In addition, the IMT and carotid plaque score were analyzed in relation to circulating levels of PAI-1 and expression of PAI-1 in internal iliac artery walls. Results: Compared with control subjects, HD patients had significantly increased common carotid artery (CCA)-IMT (P = 0.002). Atherosclerotic plaques were detected in 42 (61.76%) of HD patients and in two (4%) controls. The above ultrasonographic indices were correlated with age in HD patients (P < 0.001). A significant relationship was observed between IMT and systolic blood pressure (BP), low-density lipoprotein in HD patients (P < 0.001 and P < 0.001, respectively). In HD patients, IMT was significantly correlated with CRP and IL-6 (P < 0.001 and P < 0.001, respectively). In HD patients, a close correlation was found between serum PAI-1 level, CRP and IL-6 (P < 0.01 and P < 0.01, respectively). A close correlation was also found between PAI-1 pu value, CRP and IL-6 (P < 0.01 and P < 0.01 respectively). Serum PAI-1 level is highly correlated to PAI-1 pu value (P < 0.01). In HD patients, CCA-IMT and plaque score were correlated significantly with circulating levels of PAI-1(P < 0.01 and P < 0.05, respectively) and expression of PAI-1 in internal iliac artery walls (P < 0.01 and P < 0.05, respectively). Multivariate analysis showed that log CRP values were a strong independent contributor to CCA-IMT and plaque score (P = 0.03 and P = 0.04, respectively). Multivariate analysis showed that serum PAI-1 concentration was a strong independent correlate of CCA-IMT and carotid plaque score (P = 0.004 and P = 0.009, respectively). Multivariate analysis also showed that expression of PAI-1 in internal iliac artery walls was a strong independent correlate of CCA-IMT and carotid plaque score (P = 0.008 and P = 0.005, respectively). Conclusion: The circulating levels of PAI-1 and expression of PAI-1 in internal iliac artery walls were statistically associated with CRP, IL-6 and low-density lipoprotein cholesterol. Moreover, in HD patients, CCA-IMT and plaque score were correlated significantly with circulating levels of PAI-1 and expression of PAI-1 in internal iliac artery walls and the circulating levels of PAI-1 and expression of PAI-1 in internal iliac artery walls were independent predictors of carotid atherosclerosis including CCA-IMT and carotid plaque score. The correlations may suggest that increased circulating PAI-1 level and upregulated expression of PAI-1 in the vasculature could indicate a chronic endothelium activated state and PAI-1 may more precisely identify the risk of atherothrombosis and be useful as a target for anti-inflammatory treatment strategies.     

Association of cigarette smoking, alcohol consumption and physical activity with lower urinary tract symptoms in older American men: findings from the third National Health And Nutrition Examination Survey

OBJECTIVES: To examine the association of cigarette smoking, alcohol consumption and physical activity with lower urinary tract symptoms (LUTS) in older men. SUBJECTS AND METHODS: The study included 2797 men participating in the Third National Health and Nutrition Examination Survey (NHANES III), who were aged > or = 60 years. During an interview, LUTS, smoking history, alcohol consumption and physical activity were assessed. Cases comprised men with at least three of the symptoms of nocturia, hesitancy, weak stream and incomplete emptying. Men who had had prostate surgery unrelated to cancer were not included as cases. Controls were men with no symptoms or surgery. We adjusted for age and race in logistic regression models and used sampling weights to account for selection probability. RESULTS: Current cigarette smokers had no higher odds of LUTS than 'never' smokers, but former heavy smokers (> or = 50 pack-years) had a higher odds of LUTS than never smokers (odds ratio 2.01; 95% confidence interval 1.04-3.89). Men who drank alcohol daily had a lower chance of LUTS than non-drinkers (0.59; 0.37-0.95; P trend, 0.07). All levels of moderate and vigorous activity were statistically significantly inversely associated with LUTS (P trend, 0.06), whereas men who reported no leisure-time physical activity had a greater odds of LUTS (2.06; 1.26-3.39). CONCLUSIONS: Moderate alcohol consumption and physical activity may be protective against LUTS. Current cigarette smoking was not consistently associated with the condition. The possible association in former smokers warrants further investigation.     

Interleukin-1 is associated with inflammation and structural lung disease in young children with cystic fibrosis

Background

Little is known about the role of interleukin (IL)-1 in the pathogenesis of cystic fibrosis (CF) lung disease. This study investigated the relationship between IL-1 signalling, neutrophilic inflammation and structural lung changes in children with CF.

七氟烷对幼鼠不同脑区多聚腺苷二磷酸核糖聚合酶-1表达和远期认知功能的影响

目的 观察七氟烷对幼鼠不同脑区神经元细胞多聚腺苷二磷酸核糖聚合酶-1[Poly(ADP-ribose)polymerase-1,PARP-1]表达、远期学习记忆能力及空间探索能力的影响. 方法 出生后7d的wistar幼鼠105只采用随机数字表法随机分为模拟麻醉组(A组)、1％七氟烷麻醉2h组(B组)、1％七氟烷麻醉4h组(C组)、2％七氟烷麻醉2h组(D组)和2％七氟烷麻醉4h组(E组).麻醉结束后即刻,每组随机选3只,左心室取血进行血气分析.麻醉结束6h后,每组随机选6只幼鼠,分别取大脑皮层和海马组织,用Western blot方法检测PARP-1蛋白表达量.其余实验动物,分别在幼鼠成长至5周、8周、14周时,进行悬崖逃避实验和旷场实验. 结果 各组实验动物无缺氧和明显的CO2蓄积.与A组比较,E组海马PARP-1蛋白表达量明显增加,其他实验组无明显升高:A组(0.32±0.53),B组(0.45±0.11)、C组(0.46±0.15)、D组(0.34±0.14)、E组(0.80±0.34)(P＜0.05),各组皮层PARP-1蛋白表达量差异无统计学意义(P＞0.05).A组(0.34±0.07)、B组(0.33±0.14)、C组(0.28±0.11)、D组(0.29±0.13)、E组(0.38±0.15) (P＞0.05).5周时接受七氟烷麻醉的大鼠在旷场中平面活动及垂直活动均多于模拟麻醉幼鼠(平面活动时间/s):A组(431±32)、B组(463±27)、C组(448±31)、D组(467±23)、E组(473±25)(P＞0.05);垂直面进入时间/s:A组(112±37)、B组(169±46)、C组(152.3±44.3)、D组(150±26)、E组(129±36)(P＞0.05);8周和14周时,各组动物旷场表现差异无统计学意义(P＞0.05).5周、8周及14周时,各组动物悬崖逃避实验表现差异无统计学意义(P＞o.05). 结论 2％七氟烷作用于发育期的幼鼠4h,可导致PARP-1表达增加,诱发海马神经元凋亡;使成长中幼鼠在陌生环境中活动增加,影响其空间探索认知能力.     

The serum level of bone-specific alkaline phosphatase activity is associated with aortic calcification in osteoporosis patients

It has been suggested that there are several possible linkages between vascular calcification and osteoporosis. In addition, the processes of vascular calcification may have a common etiology with bone formation. Thus, we hypothesized that the serum levels of bone metabolic markers would be different between osteoporosis patients with and without vascular calcification. In this study, we showed that the serum level of bone-specific alkaline phosphatase activity in osteoporosis patients with abdominal aortic calcification had a higher value than in those without the calcification. On the other hand, there were no significant differences in the urine levels of type I collagen cross-linked N-telopeptides (a bone resorption marker), or in the serum levels of intact osteocalcin, Ca, and P. Bone-specific alkaline phosphatase is the most important marker for osteoblast differentiation; furthermore, the serum level of its activity may reflect the process of calcification of the aorta in osteoporosis patients.     

骨质疏松症大鼠注射重组人甲状旁腺素药动学研究

目的：研究注射用重组人甲状旁腺素rhPTH （1-84）在去卵巢骨质疏松症大鼠的药代动力学特征。方法48只大鼠（250±10）g,分成对照组（切除卵巢周围小块脂肪组织）和模型组（双侧卵巢切除）,每组8只,手术4周后皮下注射1.0、2.0、4.0 ug/kg rhPTH（1-84）,采用放射免疫分析法测定rhPTH（1-84）不同时间点的血药浓度,计算药代动力学参数。结果 rhPTH （1-84）在24～1850 pg/mL范围内线性关系良好,最低检测量为10 pg/mL;血浆提取回收率80.2％～90.6％;模型组低、中、高三个剂量的药动力学参数AUC（0-∞）分别为（24628.9±1281）、（47059.3±3311）和（96652.1±2174） ng/（ L· min）;对照组AUC（0-∞）分别为（21974.0±1587）、（42651.2±1336）和（87736.8±1938）ng/（L· min）。结论单次皮下注射rhPTH（1-84）在低、中、高3个剂量内,Cmax、AUC（0-∞）在2组动物中均呈线性代谢特征,模型组双峰特征明显,可以为设计和优化临床研究及给药方案提供重要信息。     

大鼠烧伤后库普弗细胞在促炎细胞因子产生中的作用

目的　观察大鼠严重烧伤后早期 ,库普弗细胞在肿瘤坏死因子α(TNFα)、白细胞介素(IL) 1β、IL 6产生中的作用。方法　观察 (1)烧伤血清对体外培养的大鼠库普弗细胞分泌TNFα、IL 1β、IL 6的刺激作用 ;(2 )烧伤后大鼠库普弗细胞的细胞因子mRNA表达变化 ;(3)应用库普弗细胞特异性抑制剂三氯化钆后 ,烧伤大鼠血浆内细胞因子含量变化。　结果　烧伤血清能刺激库普弗细胞释放TNFα、IL 1β、IL 6 ;大鼠烧伤后库普弗细胞TNFα、IL 1β、IL 6mRNA表达量显著升高 ;预先抑制库普弗细胞的活性 ,烧伤后血浆TNFα、IL 1β、IL 6水平均显著降低 ,分别为烧伤组的 34.71%、36 99%、33.70 %。结论　库普弗细胞是大鼠烧伤后血浆中TNFα、IL 1β、IL 6的主要来源