In ovo leptin administration affects hepatic lipid metabolism and microRNA expression in newly hatched broiler chickens

Background: A leptin-like immunoreactive substance has been found in chicken eggs and has been implicated in serving as a maternal signal to program offspring growth and metabolism. In the present study, we investigated the effects of in ovo leptin administration on hatch weight, serum and hepatic concentrations of metabolites and hormones, as well as on the expression of genes involved in hepatic lipid metabolism and the predicted microRNAs (miRNAs) targeting the affected genes. To this end we injected fertile eggs with either 0.5 μg of recombinant murine leptin or vehicle (PBS) before incubation. Results: Prenatally leptin-exposed chicks showed lower hatch weight, but higher liver weight relative to the body weight, compared to the control group. In ovo leptin treatment increased the hepatic content and serum concentration of leptin in newly hatched chickens. The hepatic contents of triglycerides (TG) and total cholesterol (Tch) were decreased, whereas the serum levels of TG, Tch and apolipoprotein B (ApoB) were increased. The hepatic mRNA expression of sterol regulator element binding protein 1 (SREBP-1c), SREBP-2, hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR) and cholesterol 7α-hydroxylase 1 (CYP7A1) was significantly up-regulated, as was the protein content of both SREBP-1c and SREBP-2 in hepatic nuclear extracts of leptin-treated chickens. Moreover, out of 12 miRNAs targeting SREBP-1c and/or HMGCR, five were significantly up-regulated in liver of leptin-treated chicks, including gga-miR-200b and gga-miR-429, which target both SREBP-1c and HMGCR. Conclusions: These results suggest that leptin in ovo decreases hatch weight, and modifies hepatic leptin secretion and lipid metabolism in newly hatched broiler chickens, possibly via microRNA-mediated gene regulation.     

Role of GRP78 in alteration of myocardium induced by intestinal endotoxemia in cirrhotic rats

AIM: To explore the role of glucose-regulated protein 78 (GRP78) in the alteration of myocardium induced by intestinal endotoxemia in cirrhotic rats. METHODS: Fifty-one male Wistar rats were randomly divided into liver cirrhosis groups of 4-week, 6-week and 8-week, and normal control groups at corresponding time points. The cardiac functions of the 8-week rats were measured. Tumor necrosis factor α(TNF-α) and malondialdehyde(MDA) in myocardial tissues were detected. The number of myocardial cells and the collagen volume fraction (CVF) were determined with toluidine blue and van Giesan staining, respectively. The expression of GRP78 and hypoxia-inducible facotr 1α(HIF-1α) was analyzed by the method of immnunohistochemistry. RESULTS: Compared with normal control group at corresponding time point, left ventricular end-diastolic pressure(LVEDP) and ±LV dp/dt_max in 8-week group were significantly decreased (P<0.05). The levels of TNF-α, MDA and CVF, the protein expression of GRP78 and HIF-1α in the myocardial tissues were significantly increased in every model group (P<0.05), and the number of myocardial cells was gradually decreased (P<0.05). Elevated levels of endotoxin in plasma were positively correlated with the levels of alanine aminotransferase (ALT),homocysteine (Hcy) and TNF-α in plasma, the levels of TNF-α, MDA and CVF, and protein levels of GRP78 and HIF-1α in the myocardial tissues (P<0.05). Elevated protein expression of GRP78 in the myocardial tissues was positively correlated with the levels of ALT, Hcy in plasma and MDA, CVF, HIF-1α protein in the myocardial tissues (P<0.05). CONCLUSION: Intestinal endotoxemia induced by liver cirrhosis may directly or indirectly lead to endoplasmic reticulum stress and overexpression of GRP78. GRP78 may be a key molecule in the pathogenesis of myocardial remodeling and functional alteration induced by liver cirrhosis.     

Effect of sorafenib on liver regeneration after partial hepatoectomy in liver cirrhotic rats

AIM: To study the effect of sorafenib on the liver regeneration after partial hepatectomy (PH) in cirrhotic rats. METHODS: Thirty Wistar rats with liver cirrhosis induced successfully with diethylnitrosamine (DEN) underwent 30% PH and then were randomly divided into 2 groups (n=15). The rats in experimental group were fed with sorafenib at dose of 30 mg·kg^-1·d^-1 from the 1st day to the 10th day after PH, while those in control group were fed with vehicle by gavage. The blood and liver tissues of the rats were collected after PH and at the end of the experiment. Liver regeneration rate (LRR) and proliferating cell nuclear antigen (PCNA) expression were assessed for determining the hepatocyte proliferation. The content of alanine transaminase (ALT), albumin (ALB), total bilirubin (TBIL), direct bilirubin (DBIL), angiogenesis related factors including vascular endothelial growth factor (VEGF), vascular endothelial growth factor receptor 2 (VEGFR-2), platelet-derived growth factor receptor β (PDGFR-β) and micro-vessel density (MVD) were measured in both groups. RESULTS: LRRs on day 10 after PH were 45.43%±3.36% and 44.21%±2.77% in experimental group and control group, respectively (P>0.05), and the expression of PCNA in hepatic tissues of the rats was not found by the method of immunohistochemistry in both groups. Liver function index had no significant difference between the 2 groups (P>0.05). However, other than VEGF, sorafenib resulted in inhibition of VEGFR-2 and PDGFR-β expression and reduction of MVD in experiment group, and significant difference between the 2 groups was observed (P<0.01). CONCLUSION: Sorafenib does not influence live regeneration after PH in liver cirrhotic rats.     

Changes of hydroxyl radical,malondialdehyde and total antioxidant capa-city in intestines after orthotopic liver autotransplantation in rats

AIM: To explore the pathological changes of small intestines after orthotopic liver autotransplantation in rats and to analyze the correlation between these changes and the levels of hydroxy radical (稯H),malondialdehyde(MDA)and total antioxidant capacity(T-AOC). METHODS: Thirty-six Sprague-Dawley rats were randomly divided into sham operation group (group S, n=6) and model group (group M). According to the period after liver reperfusion, the rats in group M were divided into 5 sub-groups: 2 h after reperfusion (group M1, n=6), 4 h after reperfusion (group M2, n=6), 8 h after reperfusion (group M3, n=6), 16 h after reperfusion (group M4, n=6), and 24 h after reperfusion (group M5, n=6). After anesthesia, the rats in group S involved laparotomy and vascular dissection without hepatic vascular exclusion and perfusion. The rats in other groups received orthotopic liver autotransplantation. The intestinal tissues starting from 5 cm to terminal ileum were removed 2 h, 4 h, 8 h, 16 h and 24 h after reperfusion. The morphological changes of intestinal epithelial basement membrane were observed under optical microscope. The levels of 稯H, MDA and T-AOC were detected. RESULTS: (1) In model groups, the morphological damages in the intestines were significant compared to group S, especially 8 h after reperfusion. The intestines showed massive epithelial lifting down the sides of villi and a few tips being denuded. The repair of pathological damage in the intestines 24 h after reperfusion was observed. (2) Compared to group S, the levels of 稯H in the intestines significantly increased in group M2, M3 and M4 (P<0.05). The levels of MDA in the intestines significantly increased in group M1, M2 and M3 (P<0.05). The levels of T-AOC significantly decreased in group M1, M2, M3 and M4 (P<0.05). CONCLUSION: Orthotopic liver autotransplantation increases the levels of 稯H and MDA, diminishes T-AOC and induces reversible pathological changes in intestines.     

三种不同给药途径建立小鼠肝硬化模型的比较

按逐步增加食用白酒浓度的方法诱导肝硬化的模型,将80只KM雄性小鼠随机分为4组,A组采用灌胃,B组采用皮下注射,C组采用腹腔注射,D组为对照组,并把20只SD大鼠随机分为皮下注射E组、对照组F组。观察各组的体重变化、死亡率和肝假小叶形成率。采用上述方法诱导7周后A～F组小鼠体重早期缓慢下降,后期缓慢增加。A组死亡5只,死亡率25%,假小叶形成率65.2%;B组死亡1只,死亡率5%,假小叶形成率92.5%;C组死亡2只,死亡率10%,假小叶形成率86.5%;E组大鼠体重早期明显下降,后期缓慢增加,死亡5只,死亡率50%,假小叶形成率66.7%;D组、F组体重明显增加,无死亡,无肝硬化形成。结果表明:小鼠皮下注射给药,逐步增加食用白酒的浓度可以缩短肝硬化形成的时间,提高形成率,降低死亡率。     

钼对鸡肝肾组织形态学的影响

为研究钼对鸡肝肾组织形态学的影响,选取80只健康2w龄雏公鸡,随机分为5组,每组16只。通过在饮水中添加不同剂量的钼酸钠(以钼离子计),建立试验动物模型:对照组(钼:0mg.L-1)、钼Ⅰ组(钼:12.5mg.L-1)、钼Ⅱ组(钼:25.0mg.L-1)、钼Ⅲ组(钼:50.0mg.L-1)、钼Ⅳ组(钼:100.0mg.L-1)。分别在试验处理第10w,采集鸡的肝脏和肾脏,固定包埋处理后,制得切片,经HE染色分析,用显微镜观察鸡肝肾组织形态学变化。肾脏和肝脏的组织形态学观测结果显示:加钼的各组与对照组相比,细胞数量增多,且有浓染,出现坏死现象,细胞核皱缩加剧,有少量充血。试验低剂量(钼Ⅰ组、钼Ⅱ组)下的钼导致鸡肝肾组织发生不明显的病理形态学变化,而高剂量组(钼Ⅲ组、钼Ⅳ组)发生明显的病理形态学变化。     

Liver disease in young rabbits infected by calicivirus through nasal and oral routes

Calicivirus infection causes rabbit haemorrhagic disease (RHD) that kills more than 90% of adult animals, whereas young rabbits are naturally resistant to this viral disease. It has been proposed that the different response of adult and young rabbits to calicivirus infection is due to absence of viral receptors in respiratory and digestive systems of young animals. We have searched for liver disease in 4-week-old rabbits inoculated with a calicivirus suspension by intranasal and oral routes. These young rabbits showed cell damage and mononuclear infiltration of the liver. The hepatic lesions were associated with mild to moderate increase in circulating transaminases. We conclude that the previously reported reduction of viral receptors in the epithelium of respiratory and digestive systems of young rabbits does not inhibit calicivirus from inducing liver disease in these hosts.     

High complication rate of an automatic Tru-Cut biopsy gun device for liver biopsy in cats

BACKGROUND: Liver biopsies taken with an automatic Tru-Cut biopsy gun device caused unexpected fatal shock reactions in cats. The goal of the present study was to determine if this biopsy device caused more frequent fatal complications than did a semiautomatic device. ANIMALS: All cats referred to the Utrecht University, between October 1, 2002, and October 31, 2004, in which ultrasound-guided Tru-Cut liver biopsies were taken. The indications for liver biopsy were increased liver enzyme activity, increased bile acid concentrations, ultrasonographic abnormalities of the liver, ultrasonographic abnormalities of the bile ducts, or some combination of these findings. Coagulation parameters were normal. METHODS: From October 1, 2002, until October 31, 2003, 26 cats were biopsied with an automatic biopsy device. Between November 1, 2003, and October 31, 2004, 19 cats underwent liver biopsy with a semiautomatic biopsy device. RESULTS: In the first period. 5 of the 26 cats (19%) developed severe shock within 15 minutes. Resuscitation was not successful. In the second period, none of the 19 cats experienced any major adverse effect. There were no significant differences between the 2 groups with respect to diagnosis, clinical signs, clinicopathologic findings, or the use of anesthetics. CONCLUSIONS AND CLINICAL IMPORTANCE: We conclude that the difference in complication rate is explained by the biopsy technique used. The pressure wave, which occurs when firing the automatic device, may have caused intense vagotonia and shock. Use of this automatic biopsy device should be avoided in cats because of the high risk of fatal complications.     

乳牛肝功能与维生素D3代谢及骨软病关系的研究

通过血常规，血清钙，无机磷，碱性磷酸酶活及其同工酶酶谱，尾椎Ｘ线检查等方法，在北京市郊区某农场，选出１０头健康成年黑白花乳牛作为对照组，１０头骨软病乳牛作为试验组。分别对其肝功能，血清维生素Ｄ３，２５－羟维生素Ｄ３（２５－ＯＨ－Ｄ３）和１，２５－双羟维生素Ｄ３（１，２５－（ＯＨ）２－Ｄ３）进行测定。结果表明，骨软病乳牛血清硫酸锌浊度及γ－球蛋白明显高于健康水平（Ｐ〈０．０５和Ｐ〈０．０１），而血清     

Effects of diazinon at different doses on rat liver and pancreas tissues

Diazinon is one of the most widely used organophosphates in agriculture. Toxic effects of diazinon are due to the inhibition of acetylcholinesterase, an enzyme needed for proper nervous system function. This study was designed to investigate the effects of diazinon at different doses on pancreas and liver tissues and in which dose level diazinon shows its effects. Sixty male Wistar albino rats were included in this study. Animals were initially divided into control and diazinon given groups. There were 10 animals in the control group and 50 animals in diazinon administered group. The latter was divided into five equal subgroups: 25, 50, 100, 200 and 300 mg/kg of diazinon administered groups. Control group was given only saline. All animals in 300 mg/kg diazinon group died. After 24 h, rats were sacrificed under ether anesthesia. Tissue and blood samples were taken for biochemical and histopathological analysis. Sample tissues were examined under light microscope. In biochemical analysis, AST, ALT, LDH, amylase and lipase enzyme activities were measured. One-way ANOVA test was used to compare the groups. In 200 mg/kg diazinon given group, it has been observed some histopathological changes in pancreas and liver tissues. Cholinesterase activities were significantly decreased and alkaline phosphatase levels were increased in all diazinon given groups, when compared with the controls. There was statistically significant difference between the control and diazinon given groups by means of serum amylase, lipase, ALT and AST activities (p < 0.05). LDH activities were significantly increased in 100 and 200 mg diazinon given groups, when compared with the controls (p < 0.05). Histopathological changes were observed only in 200 mg diazinon given group. This evidence suggest that diazinon effect is dose dependent and this is possibly 10-15% of the LD₅₀ dose (200 mg/kg), which cause acute pancreatitis and histopathological changes in liver.