Safety and efficacy of a novel plastic stent coated with stone-dissolving agents for the treatment of biliary stones in a porcine model.

BACKGROUND AND STUDY AIM: We previously reported on a plastic stent that was coated with ethylenediaminetetraacetic acid (EDTA) and sodium cholate, which dissolved common bile duct (CBD) stones ex vivo. The aim of this study was to investigate the safety and efficacy of such stents on biliary stones in a live porcine model. METHODS: Stents without coating or with degradable membranes containing 0 % or 50 % EDTA and sodium cholate were inserted together with human CBD stones into the porcine CBD. Serum laboratory variables, histological examinations of the bile duct, and the weight change in stones were compared during and after stent placement for 6 months. RESULTS: A total of 16 pigs were included (5 no coating, 5 0 % coating, 6 50 % coating). Biliary stones showed decreased weight in all groups; however, stones in the group with 50 % coated stents showed a greater reduction in weight compared with the no coating and the 0 % coating groups (269 ±â€Š66 mg vs. 179 ±â€Š51 mg [P = 0.09]; 269 ±â€Š66 mg vs. 156 ±â€Š26 mg [P = 0.01], respectively). CONCLUSIONS: The plastic stent coated with 50 % agent enhanced CBD stone dissolution in vivo and may be a promising tool for patients with difficult biliary stones.

Impaired iNOS-sGC-cGMP signalling contributes to chronic hypoxic and hypercapnic pulmonary hypertension in rat.

Nitric oxide (NO) is an important vascular modulator in the development of pulmonary hypertension. NO exerts its regulatory effect mainly by activating soluble guanylate cyclase (sGC) to synthesize cyclic guanosine monophosphate (cGMP). Exposure to hypoxia causes pulmonary hypertension. But in lung disease, hypoxia is commonly accompanied by hypercapnia. The aim of this study was to examine the changes of sGC enzyme activity and cGMP content in lung tissue, as well as the expression of inducible nitric oxide synthase (iNOS) and sGC in rat pulmonary artery after exposure to hypoxia and hypercapnia, and assess the role of iNOS-sGC-cGMP signal pathway in the development of hypoxic and hypercapnic pulmonary hypertension. Male Sprague-Dawley rats were exposed to hypoxia and hypercapnia for 4 weeks to establish model of chronic pulmonary hypertension. Weight-matched rats exposed to normoxia served as control. After exposure to hypoxia and hypercapnia, mean pulmonary artery pressure, the ratio of right ventricle/left ventricle+septum, and the ratio of right ventricle/body weight were significantly increased. iNOS mRNA and protein levels were significantly increased, but sGC α(1) mRNA and protein levels were significantly decreased in small pulmonary arteries of hypoxic and hypercapnic exposed rat. In addition, basal and stimulated sGC enzyme activity and cGMP content in lung tissue were significantly lower after exposure to hypoxia and hypercapnia. These results demonstrate that hypoxia and hypercapnia lead to the upregulation of iNOS expression, downregulation of sGC expression and activity, which then contribute to the development of pulmonary hypertension.

Success rate and complications of endoscopic extraction of common bile duct stones over 2 cm in diameter.

BACKGROUND: Clinically, common bile duct (CBD) stones >2 cm are difficult to remove by endoscopic retrograde cholangiopancreatography (ERCP). To evaluate this observation, the rates of successful clearance of CBD stones and complications were compared between ERCP extraction of CBD stones of >2 cm and <2 cm in diameter. METHODS: All patients who had undergone endoscopic extraction of CBD stones at the Endoscopy Center of Shanghai First People's Hospital from May 2004 to May 2008 were reviewed. Patients with CBD stones of >2 cm in diameter were enrolled in the >2 cm group. Two matched controls with CBD stones of <2 cm in diameter were selected for each enrolled patient (<2 cm group). Patient characteristics, success rates, and complications during and after ERCP were compared. RESULTS: Seventy-two patients constituted the >2 cm group and 144 patients were in the <2 cm group. No significant differences were found in the patient characteristics, except for stone size and CBD diameter. Both the overall success rate and the success rate in the first ERCP session were lower in the >2 cm group (77.8% and 58.3%, respectively) than in the <2 cm group (91.7% and 83.3%, P<0.01). During ERCP, the incidence of hypoxemia (30.6%) and hemorrhaging papillae (18.1%) in the >2 cm group was higher than in the <2 cm group (13.2% and 6.3%, P<0.05). After ERCP, the rates of delayed papillae hemorrhage (13.9%), hyperamylasemia (23.6%), acute pancreatitis (8.3%) and biliary infection (18.1%) were higher in the >2 cm group than in the <2 cm group (3.5%, 11.1%, 2.1%, and 2.8%, respectively, P<0.05). CONCLUSION: The success rate of endoscopic extraction of CBD stones of >2 cm in diameter was lower but the complication rate was higher than that of stones of <2 cm in diameter.

lncRNA FGD5­AS1 promotes breast cancer progression by regulating the hsa­miR­195­5p/NUAK2 axis.

Breast cancer is the second most prevalent cancer in women worldwide. Long non­coding RNAs (lncRNAs) have been identified as important regulators of tumorigenesis and tumor metastasis. lncRNA FGD5­AS1 has been previously reported as a carcinogenic gene, however its role in breast cancer has yet to be investigated. The present study aimed to understand the function of lncRNA FGD5­AS1 in breast cancer and examine the underlying molecular mechanisms. Sample tissues for downstream gene expression profiling were collected from patients with breast cancer (n=23). The effect of FGD5­AS1 overexpression on cell viability, invasion and migration has been studied in breast cancer cells (MDA­MB­231). Changes in glycolysis were monitored by comparing glucose consumption, lactate production and ATP levels. Using StarBase and TargetScan databases a putative interaction between FGD5­AS1, miR­195­5p and SNF1­like kinase 2 (NUAK2) was predicted in silico. Expression levels of FGD5­AS1, has­miR­195­5p and NUAK2 were validated by reverse transcription­quantitative PCR and interactions were validated using dual­luciferase reporter assays and RNA pull­down. High expression of lncRNA FGD5­AS1 was detected in breast cancer tissue samples and disease model cell lines. Silencing of FGD5­AS1 led to decreased cell proliferation, migration and invasion. It was identified that at a molecular level FGD5­AS1 serves as a sponge of miR­195­5p and alters the expression of its downstream target gene NUAK2. In breast cancer lncRNA FGD5­AS1 serve a key role in glycolysis and tumor progression via the miR­195­5p/NUAK2 axis. The findings of the present study indicated FGD5­AS1 as a candidate target for intervention in patients with breast cancer.

Characterization of high-fat, diet-induced, non-alcoholic steatohepatitis with fibrosis in rats.

An ideal animal model is necessary for a clear understanding of the etiology, pathogenesis, and mechanisms of human non-alcoholic steatohepatitis (NASH) and for facilitating the design of effective therapy for this condition. We aimed to establish a rat model of NASH with fibrosis by using a high-fat diet (HFD). Male Sprague-Dawley (SD) rats were fed a HFD consisting of 88 g normal diet, 10 g lard oil, and 2 g cholesterol. Control rats were fed normal diet. Rats were killed at 4, 8, 12, 16, 24, 36, and 48 weeks after HFD exposure. Body weight, liver weight, and epididymal fat weight were measured. Serum levels of fasting glucose, triglyceride, cholesterol, alanine aminotransferase (ALT), free fatty acids (FFA), insulin, and tumor necrosis factor-alpha (TNF-alpha) were determined. Hepatic histology was examined by H&E stain. Hepatic fibrosis was assessed by VG stain and immunohistochemical staining for transforming growth factor beta 1 (TGF-beta1), and alpha-smooth-muscle actin (alpha-SMA). The liver weight and liver index increased from week 4, when hepatic steatosis was also observed. By week 8, the body weight and epididymal fat weight started increasing, which was associated with increased serum levels of FFA, cholesterol, and TNF-alpha, as well as development of simple fatty liver. The serum ALT level increased from week 12. Steatohepatitis occurred from weeks 12 through 48. Apparent hepatic perisinosodial fibrosis did not occur until week 24, and progressed from week 36 to 48 with insulin resistance. Therefore, this novel model may be potentially useful in NASH study.

Association between non-invasively diagnosed hepatic steatosis and chronic kidney disease in Chinese adults on their health check-up.

OBJECTIVE: To explore the association between chronic kidney disease (CKD), graded by the estimated glomerular filtration rate (eGFR), and non-alcoholic fatty liver disease (NAFLD) using controlled attenuation parameter (CAP) and fatty liver index (FLI) values in Chinese adults undergoing routine health examinations. METHODS: A total of 731 adult participants without diabetes mellitus or significant alcohol consumption who underwent routine health examinations were included. Their eGFR, CAP, FLI and abdominal ultrasonography results were assessed. RESULTS: The prevalence of ultrasound-diagnosed NAFLD and CKD (eGFR <60 mL/min per 1.73 m2 ) was 36.1% and 6.6%, respectively. CKD was more common in NAFLD patients than in those without (10.6% vs 4.3%, P < 0.001). The CAP and FLI values were significantly higher in the NAFLD group than in those without, but the change in the eGFR was negligible between the two groups. eGFR was negatively correlated with CAP (r = -0.189, P = 0.003) and FLI values (r = -0.130, P = 0.045). Moreover, eGFR was significantly lower in participants with CAP >292 dBm or FLI ≥60 than in those with CAP <238 dBm or FLI <30, respectively (both P < 0.05). The CAP value (odds ratio [OR] 1.099, 95% confidence interval [CI] 1.091-1.108, P = 0.021) was an independent risk factor for CKD. CONCLUSIONS: A diagnosis of hepatic steatosis is related to an increased risk of CKD among non-alcoholic and non-diabetic Chinese adults regardless of whether the diagnosis was acquired via ultrasound, CAP or FLI. Increased hepatic lipid content may contribute to CKD development.

[Upregulating expressions of hepatic lipopolysaccharide receptors in nonalcoholic steatohepatitic rats].

OBJECTIVE: The expression of hepatic lipopolysaccharide (LPS) receptors in a rat nonalcoholic steatohepatitis (NASH) model was studied in order to explore the pathogenesis of NASH. METHODS: Forty-five male SD rats were fed with a high fat diet. These rats were sacrificed after high fat feeding at 8, 12, 16, 24 weeks. Hepatic expressions of CD14 were observed by immunohistochemistry and expressions of TLR4 were detected by RT-PCR. Hepatic expressions and serum levels of TNFa were measured by RT-PCR and ELISA. Some rats fed with normal rat food served as controls. RESULTS: At the 8th week fatty livers appeared, and hepatic expressions of CD14 (25.9+/-1.9) and TLR4mRNA (1.75+/-0.81) were upregulated compared to those in the control group (25.9+/-1.9 vs 12.4+/-0.7, 1.75+/-0.81 vs 0.98+/-0.33, P < 0.01, t > 2.756 and P < 0.05, t > 2.045). The hepatic expressions of the two kinds of receptors increased with the appearance of NASH at week 12 (61.8+/-1.9 and 1.88+/-0.72, P < 0.01, t > 2.756 and P < 0.05, t > 2.045), They reached to their peaks at week 16 (71.5+/-1.3 and 5.64+/-0.87, both P < 0.01 and t > 2.756), and decreased slightly at week 24 (67.7+/-6.6 and 4.98+/-0.72, both P < 0.01 and t > 2.756). Hepatic expressions and serum levels of TNFa also increased starting at week 8, and remained at that high level from week 8 to week 24. CONCLUSION: The hepatic expressions of CD14 and TLR4 were up-regulated gradually in the established rat NASH model. It may be one of the factors responsible for the increase of hepatic sensitivity to LPS injury of the NASH rats and may play an important role in the pathogenesis of NASH.

Evaluating the Relationship Between Metabolic Syndrome and Liver Biopsy-Proven Non-Alcoholic Steatohepatitis in China: A Multicenter Cross-Sectional Study Design.

INTRODUCTION: Non-alcoholic steatohepatitis (NASH) is a serious form of non-alcoholic fatty liver disease (NAFLD) that can progress to advanced fibrosis, cirrhosis, and hepatocellular carcinoma. Differentiating between non-alcoholic fatty liver (NAFL) and NASH/advanced fibrosis is an important step in the management of NAFLD. Metabolic syndrome (MS) and its components are important risk factors for NAFLD, and NASH is thought to be the hepatic injury of MS. The prevalence of NASH among NAFLD patients with MS is thought to be high. In China, NAFLD is a relatively new public health concern, and the current prevalence of NASH among Chinese liver biopsy-proven NAFLD patients with and without MS is not known. METHODS: This multicenter, cross-sectional study will investigate the prevalence of NASH in approximately 480 Chinese NAFLD patients. Patients will be eligible for enrollment if they have biopsy-proven NAFLD and if their liver biopsies are available for rereading. For our analysis, patients will be stratified according to the presence/absence of MS, and the prevalence of NASH in the subgroups will be compared. Other possible tests that could indicate a risk of NASH, including transient elastography, ultrasonography, cytokeratin-18, liver function tests, and others, will be studied in an effort to derive a practical, noninvasive predictive model for NASH. DISCUSSION: Patients with NAFL who have MS may also have a very high risk of developing NASH. The present study will inform about the risk of NASH in Chinese liver biopsy-proven NAFLD patients with and without MS. TRIAL REGISTRATION: This study registered at http://www.chictr.org.cn (registration number: ChiCTR-OOC-16007902). FUNDING: Sanofi (China) Investment Co., Ltd.

Disease-specific miR-34a as diagnostic marker of non-alcoholic steatohepatitis in a Chinese population.

AIM: To assess disease-specific circulating microRNAs (miRNAs) in non-alcoholic steatohepatitis (NASH) patients. METHODS: A total of 111 biopsy-proven non-alcoholic fatty liver disease (NAFLD) or chronic hepatitis B (CHB) patients and healthy controls from mainland China were enrolled to measure their serum levels of miR-122, -125b, -146b, -16, -21, -192, -27b and -34a. The correlations between serum miRNAs and histological features of NAFLD were determined. The diagnostic value of miRNA in NASH and significant fibrosis was analyzed and compared with that of cytokeratin-18 (CK-18), fibrosis-4 (FIB-4), and aspartate aminotransferase to platelet ratio index (APRI), respectively. RESULTS: Circulating miR-122, -16, -192 and -34a showed differential expression levels between NAFLD and CHB patients, and miR-34a had an approximately 2-fold increase in NAFLD samples compared with that of CHB samples (P < 0.01). Serum miR-122, -192 and -34a levels were correlated with steatosis (R = 0.302, 0.323 and 0.470, respectively, P < 0.05) and inflammatory activity (R = 0.445, 0.447 and 0.517, respectively, P < 0.01); only serum miR-16 levels were associated with fibrosis (R = 0.350, P < 0.05) in patients with NAFLD. The diagnostic value of miR-34a for NASH (area under the receiver operating characteristic, 0.811, 95%CI: 0.670-0.953) was superior to that of alanine aminotransferase, CK-18, FIB-4 and APRI in NAFLD, but miR-16 showed a limited performance in the diagnosis of significant fibrosis in NASH. CONCLUSION: Circulating miR-34a may serve as a disease-specific noninvasive biomarker for the diagnosis of NASH.

Effect of lactulose on establishment of a rat non-alcoholic steatohepatitis model.

AIM: To explore the relationship between changes of intestinal environment and pathogenesis of non-alcoholic steatohepatitis (NASH). METHODS: Forty-two Sprague-Dawley rats were randomly divided into model group (n = 24), treatment group (n = 12), and control group (n = 6). The rats of model and treatment groups were given high-fat diet, and those of the control group were given normal diet. Furthermore, the rats of treatment group were given lactulose after 8 wk of high-fat diet. Twelve rats of the model group were killed at 8 wk of high-fat diet. At the 16 wk the rats of treatment group, control group, and the rest of the model group were killed. The serum levels of aminotransferase were measured and the histology of livers was observed by H and E staining. RESULTS: The livers of rats presented the pathological features of steatohepatitis with higher serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the model group after 16 wk. Compared to the model group, the serum levels of ALT and AST in treatment group decreased significantly and were close to the normal group, and the hepatic inflammation scores also decreased markedly than those in the model group after 16 wk (5.83+/-2.02 vs 3.63+/-0.64, P<0.05), but were still higher than those in the model group after 8 wk (3.63+/-0.64 vs 1.98+/-0.90, P<0.05). However, the degree of hepatic steatosis had no changes in treatment group compared to the model group after 16 wk. CONCLUSION: Lactulose could ameliorate the hepatic inflammation of rats with steatohepatitis induced by fat-rich diet, but could not completely prevent the development of steatohepatitis. It is suggested that intestinal environmental changes such as intestinal bacteria overgrowth, are one of the important factors in the pathogenesis of NASH.

Effects of ursodeoxycholic acid and/or low-calorie diet on steatohepatitis in rats with obesity and hyperlipidemia.

AIM: To evaluate the effects of ursodeoxycholic acid (UDCA) and/or low-calorie diet (LCD) on a rat model of nonalcoholic steatohepatitis (NASH). METHODS: Fifty-five Sprague-Dawley rats were divided into five groups. The control group (n = 9) was fed with standard rat diet for 12 wk, NASH group (n = 10) was fed with high-fat diet consisted of normal diet, 10% lard oil and 2% cholesterol for 12 wk, UDCA group (n = 10) was fed with high-fat diet supplemented with UDCA at a dose of 25 mg/(kg.d) in drinking water for 12 wk, LCD group (n = 10) was fed with high-fat diet for 10 wk and then LCD for 2 wk, and UDCA+LCD group (n = 15) was fed with high-fat diet for 10 wk, followed by LCD+UDCA for 2 wk. At the end of the experiment, body weight, serum biochemical index, and hepatopathologic changes were examined. RESULTS: Compared with the control group, rats in the NASH group had significantly increased body weight, liver weight, and serum lipid and aminotransferase levels. All rats in the NASH group developed steatohepatitis, as determined by their liver histology. Compared with the NASH group, there were no significant changes in body weight, liver weight, blood biochemical index, the degree of hepatic steatosis, and histological activity index (HAI) score in the UDCA group; however, body and liver weights were significantly decreased, and the degree of steatosis was markedly improved in rats of both the LCD group and the UDCA+LCD group, but significant improvement with regard to serum lipid variables and hepatic inflammatory changes were seen only in rats of the UDCA+LCD group, and not in the LCD group. CONCLUSION: LCD might play a role in the treatment of obesity and hepatic steatosis in rats, but it exerts no significant effect on both serum lipid disorders and hepatic inflammatory changes. UDCA may enhance the therapeutic effects of LCD on steatohepatitis accompanied by obesity and hyperlipidemia. However, UDCA alone is not effective in the prevention of steatohepatitis induced by high-fat diet.

[Expression of uncoupling protein 2 and its relationship to the content of adenosine triphosphate in the nonalcoholic fatty livers of rats fed a high-fat diet].

OBJECTIVE: To investigate the expression of uncoupling protein 2 (UCP2) and its relationship to the content of adenosine triphosphate (ATP) in livers of nonalcoholic fatty liver disease (NAFLD) rats fed a fat-rich diet. METHODS: To produce a NAFLD model, a fat-rich diet, consisting of 10% lard oil + 2% cholesterol, was given to Sprague-Dawley rats for a period of 8, 12, 16 and 24 weeks. The normal control rats were fed normal diets. The expressions of UCP2 in the liver were detected by immunohistochemistry and semi-quantitative RT-PCR. The content of ATP of liver was measured by fluorometry. RESULTS: Simple fatty livers were observed in the model group after 8 weeks. From 12 week to 24 week, the livers of the model group rats gradually progressed from simple steatohepatitis to steatohepatitis with pericellular fibrosis. Both immunohistochemistry and semi-quantitive RT-PCR suggested the up-regulated expression of UCP2 in these NAFLD rat livers. The hepatic expression of UCP2 mRNA in the model group was increased with time, and peaked in 24 week by 4.2 times compared to the control group ( t = 16.474, P < 0.01). The ATP content of livers was significantly reduced in the model group compared with the control group at 16 weeks [(2.97+/-0.48) x 10(-8) micromol/g vs. (2.25+/-0.55) x 10(-8) micromol/g, t = 2.419, P < 0.05] and 24 weeks [(2.97+/-0.48) x 10(-8) micromol/g vs. (1.99+/-0.66) x 10(-8) micromol/g, t = 3.248, P < 0.01]. Furthermore, there was a negative correlation between the UCP2 mRNA expression and the content of ATP in the livers of the NAFLD group (r = -0.93, P < 0.01). CONCLUSIONS: The rat model of NAFLD could be replicated sucessfully by feeding a fat-rich diet for 24 weeks, and the mRNA and its protein of UCP2 were expressed un-regulated in livers of NAFLD. The increasing UCP2 might play a role in the reduction of ATP content in livers of the NAFLD rats.

Effects of low-calorie diet on steatohepatitis in rats with obesity and hyperlipidemia.

AIM: To evaluate the effects of low calorie diet (LCD) on nonalcoholic steatohepatitis (NASH) in rats with obesity and hyperlipidemia. METHODS: 29 Sprague-Dawley (SD) rats were randomly divided into three groups. The animals in control (n=9) and NASH group (n=10) were fed on standard rat diet and high fat diet respectively for 12 weeks, ten rats in LCD group were fed on high fat diet for 10 weeks and then low calorie diet for 2 weeks. At the end of the experiment, body weight, abdominal adipose content, liver function, and hepatopathological changes were examined to evaluate the effect of different feeding protocols on the experimental animals. RESULTS: There was no death of animal in the experimental period. All rats in the NASH group developed steatohepatitis according to liver histological findings. Compared with the control group, body weight (423.5+/-65.2 vs 351.1+/-43.0 g, P<0.05), abdominal adipose content (14.25+/-1.86 vs 9.54+/-1.43, P<0.05), liver index (3.784+/-0.533 vs 2.957+/-0.301 %, P<0.01), total serum cholesterol (1.60+/-0.41 vs 1.27+/-0.17 mmol/L,P<0.05) and free fatty acids (728.2+/-178.5 vs 429.2+/-96.7 mmol/L, P<0.01), serum alanine aminotransferase (1,257.51+/-671.34 vs 671.34+/-118.57 nkat/L, P<0.05) and aspartic aminotransferase (2,760.51+/-998.66 vs 1,648.29+/-414.16 nkat/L, P<0.01) were significantly increased in the NASH group. Whereas, when rats were fed on LCD protocol, their body weight (329.5+/-38.4 g, P<0.01), abdominal adipose content (310.21+/-1.52 g, P<0.05), liver index (3.199+/-0.552 %, P<0.05), and serum alanine aminotransferase (683.03+/-245.49 nkat/L, P<0.05) were significantly decreased, and the degree of hepatic steatosis (P<0.05) was markedly improved compared with those in the NASH group. However, no significant difference was found in serum lipid variables and hepatic inflammatory changes between the two groups. CONCLUSION: LCD might play a role in the prevention and treatment of obesity and hepatic steatosis in SD rats, but it exerts no significant effects on both serum lipid disorders and hepatic inflammatory changes.

[Study on soluble guanylate cyclase in pulmonary hypertension rat model].

OBJECTIVE: To investigate the mRNA and protein expressions of soluble guanylate cyclase (sGC) and its enzyme activity in pulmonary hypertension rat model which was reproduced by hypoxia and hypercapnia. METHODS: Male Sprague-Dawley rats were randomly divided into hypoxic and hypercapnic group (HH group) and control group (C group). The protein expressions of sGC alpha(1) and sGC beta(1) subunits in medial and small pulmonary arteries was measured by immunohistochemistry method with a polycolonal antibody. The mRNA expression of sGC alpha(1) subunit of lung tissue was detected by in situ hybridization using sGC oligonuclear probe. Basal sGC enzyme activity and sodium nitroprusside (SNP)-stimulated sGC activity in lung homogenates were assayed with enzyme kinetic analysis. RESULTS: The mean pulmonary artery pressure (mPAP), the ratio of right ventricle/left ventricle + septum [RV/(LV + S)] and the ratio of right ventricle/body weight (RV/BW) were significantly higher in HH group than those in C group. The protein expressions of sGC alpha(1) and sGC beta(1) subunits and mRNA expressions of sGC alpha(1) subunit were significantly decreased in the small and medium pulmonary arteries in HH group as compared with those in C group (P < 0.01). Basal sGC enzyme activity in HH group (32.03 +/- 7.17 pmol cGMP synthesized.mg protein(-1).min(-1)) was significantly lower than that in C group (114.76 +/- 18.37 pmol cGMP synthesized.mg protein(-1).min(-1), P < 0.01). The SNP significantly increased the sGC enzyme activity but the SNP-stimulated sGC enzyme activity of lung homogenates in HH group was significantly lower than that in C group (P < 0.01). CONCLUSIONS: The mRNA and protein expressions of sGC subunits and their enzyme activities in lung tissue of pulmonary hypertension rat model were reduced.

[Dynamic changes of plasma levels of prostacycline and thromboxane A2 and their correlation with the severity of hepatic injury in rats with nonalcoholic fatty liver disease].

OBJECTIVE: To investigate the dynamic changes of plasma levels of prostacycline (PGI2) and thromboxane A2 (TXA2) and their relationship with the severity of hepatic injury in rats with nonalcoholic fatty liver disease (NAFLD). METHODS: We established a NAFLD model, with a fat-rich diet consisting of 10% lard oil + 2% cholesterol, which was given to Sprague-Dawley rats (n=48) for a period of 8, 12, 16 and 24 weeks. The other rats were fed standard diets and were used as normal controls (n=24). At sacrifice, liver pathology scores were evaluated and plasma levels of PGI2, its stable metabolic product 6-keto-PGF1 alpha and TXA2, and TXB2 were determined by radioimmunoassay. RESULTS: Simple fatty livers were observed in the model group at 8 weeks. From 12 weeks to 24 weeks, the livers gradually progressed from simple steatohepatitis to liver fibrosis. Plasma levels of TXB2 in the model group increased higher than in the control group after 8 weeks [(52.4+/-3.15) ng/L vs (41.1+/-1.45) ng/L] and continued to increase over time, with the highest levels at 24 weeks [(117.7+/-7.47) ng/L]. A strong positive correlation (r=0.537) was seen between plasma TXB2 levels and the severity of liver injury. Plasma 6-keto-PGF1 alpha concentrations decreased in the model group in comparison with the control group after 8 weeks [(31.1+/-1.62) ng/L vs (36.5+/-1.68) ng/L] and continued to decrease over time, with the lowest concentrations at 24 weeks [(3.4+/-2.43) ng/L t=3.77]. A negative correlation was shown between the 6-keto-PGF1 alpha level and the severity of the liver injury. CONCLUSION: A rat model of NAFLD was established successfully by feeding a fat-rich diet for 24 weeks. In this model, the imbalance of plasma PGI2 and TXA2 levels (increased TXB2 and decreased 6-keto-PGF1 alpha levels) may play a role in the pathogenesis of experimental NAFLD.

[Change of serum endotoxin level in the progress of nonalcoholic steatohepatitis in rats].

OBJECTIVE: To explore the role of endotoxin in the pathogenesis of nonalcoholic steatohepatitis (NASH). METHODS: Rat models of NASH were established by giving a fat-riched diet. These rats were sacrificed at the 4th, 8th, 12th, 16th and 24th weeks during the study. The other rats fed with normal diet were taken as normal controls at the same stage during the study. The blood of abdominal aorta was obtained and the levels of serum endotoxin, tumor necrosis factor-alpha (TNF-a), and interleukin-1 beta (IL-1 b) were measured. The expression of CD(14) and lysozyme in rats' livers were detected by immunohistochemistry. RESULTS: Rat models of NASH with liver fibrosis were established successfully. The levels of endotoxin in aorta blood of NASH rats increased significantly at the 24th week (0.23 EU/L 0.06 EU/L vs 0.15 EU/L 0.03 EU/L, t>2.179, p <0.05) while the expression of CD(14) increased from the 4th week, and the Kupffer cells expressing lysozyme were activated, then kept increasing activation through the study. In NASH rats, the levels of serum TNF-a increased from the 8th week (26.39 pg/ml 24.21 pg/ml vs 9.82 pg/ml 9.29 pg/ml, t>2.145, p < 0.05) and serum IL-1beta increased from the 16th week (23.76 pg/ml 21.81 pg/ml vs 6.25 pg/ml 2.98 pg/ml, t>2.145, p<0.05). CONCLUSION: Liver injury results from endotoxin existing in NASH rats which may play an important role in the pathogenesis of NASH by activating Kupffer cells and inducing the production of cytokines, such as TNF-a.

[Role of lipid peroxidation in hepatic ischemia-reperfusion injury and effect of L-Arginine].

OBJECTIVE: To study the role of lipid peroxidation during hepatic ischemia-reperfusion injury (HIRI) and the effects of L-Arginine (L-Arg). METHODS: The rabbits and patients who underwent elective hepatic surgery were randomly divided into two groups respectively, HIRI group and L-Arg group.Plasma malondialdehyde (MDA) and alanine aminotransferase (ALT) were measured before ischemia 45 minutes (rabbits) or 25 minutes(patients) and 45 minutes(rabbits) or 25 minutes (patients) after reperfusion. RESULTS: As compared with pre-ischemia, MDA and ALT increased during ischemia 45 minutes (or 25 minutes) in rabbits and patients, P<0.05 or P<0.01. Treatment with L-Arg could markedly reduce the elevation of mentioned biochemical parameters during hepatic ischemia. In rabbits MDA decreased on hepatic but the different were not significant (P>0.05), ALT decreased (P<0.05). In patients MDA and ALT both decreased on hepatic(both P<0.01). After reperfusion, MDA and ALT all decreased in rabbits and patients (all P<0.01). CONCLUSION: These data suggest that lipid peroxidation can play an important role in the happening and developing of HIRI. Treatment with L-Arg may attenuate ischemia-reperfusion injury by antagonizing lipid peroxidation.

[Effects of L-arginine on the function of platelet aggregation during hepatic ischemia/reperfusion injury].

OBJECTIVE: To explore the effects of L-arginine (L-Arg) on the function of platelet aggregation during hepatic ischemia-reperfusion injury (HIRI). METHODS: The changes in maximum aggregating rate of circulating platelets (Pt(max)), its maximum aggregating time (PtT) as well as its aggregating slopes (PtS) were measured. Effects of L-Arg on those parameters were observed during HIRI in 20 rabbits and 18 patients who were scheduled for elective hepatic surgery. RESULTS: Pt max and PtS all increased significantly (P<0.05 and P<0.01), while PtT decreased remarkably (both P<0.05) during HIRI of rabbits and patients. After treatment with L-Arg, the abnormal changes of parameters as above were all alleviated remarkably (P<0.05 and P<0.01). CONCLUSION: It is indicated that L-Arg can effectively regulate the function of platelet aggregation during HIRI.

Nucleotide oligomerization domain 2 contributes to the innate immune response in THCE cells stimulated by Aspergillus fumigatus conidia.

AIM: To investigate the expression of nucleotide oligomerization domain 2 (NOD2) in the immortalized human corneal epithelial cell line (THCE), and its role in the innate immune response triggered by inactive Aspergillus fumigatus (Af) conidia. METHODS: The normal THCE cells were investigated as controls. After incubation with inactive Af conidia for 0.5, 2, 4, 6, and 8 hours, THCE cells were harvested, mRNA expression of NOD2 and receptor interacting protein 2 (RIP2) was detected by RT-PCR. Intracellular proteins including NOD2, NF-κB and proinflammatory cytokines such as TNF-α, IL-8, IL-6 in the cell supernatant were analyzed by ELISA. RESULTS: Our data indicate that NOD2 expressed in the normal THCE cells. After triggered by the inactive Af conidia, the expression of NOD2, RIP2 mRNA and the secretion of NOD2, NF-κB, TNF-α, IL-8, IL-6 both increased in a time-depended manner, and reached the peak point at 4, 6, 6, 4, 6, 6, 4 hours, respectively. And after pretreated with NOD2 neutralizing antibody, the expression of RIP2, NF-κB, TNF-α, IL-8 both decreased dramatically at the peak point, while the secretion of IL-6 changed little. CONCLUSION: The results of this study suggest that NOD2 exists and expresses in the THCE cells, and contributes to the innate immune responses triggered by inactive Af conidia by induction of proinflammatory cytokines such as TNF-α and IL-8 through the NF-κB pathway.