灵芝孢子油对四氯化碳联合高脂饮食诱导大鼠肝纤维化的作用研究

探究灵芝孢子油(GSO)对四氯化碳(CCl₄)联合高脂饮食诱导的大鼠肝纤维化的改善作用及机制。将雄性SPF级SD大鼠分为空白对照组、模型对照组、阳性药物组和灵芝孢子油低、中、高剂量组(人体推荐量的5、15、30倍)。采用CCl₄联合高脂饲料诱导6周建立大鼠肝纤维化模型,造模过程中灌胃GSO干预8周。通过检测血清生理生化指标和大鼠肝脏组织形态、氧化应激水平、纤维化相关蛋白,评价GSO对肝纤维化的保护作用。研究结果表明,中、高剂量GSO能够显著提升肝纤维化大鼠的存活率,使得大鼠存活率恢复至空白对照组水平。病理染色结果表明,GSO处理的大鼠肝组织纤维化得到不同程度的改善,GSO中、高剂量处理显著降低大鼠肝脏胶原面积占比及面密度。GSO高剂量干预可显著降低大鼠血浆肝功能相关指标(谷丙转氨酶、谷草转氨酶、总胆红素、碱性磷酸酶)水平,减少血浆中肝纤维化指标(透明质酸、层黏蛋白、Ⅳ型胶原、羟脯氨酸)水平。同时,高剂量GSO干预还显著降低肝组织中丙二醛含量,提高还原型谷胱甘肽含量与超氧化物歧化酶活性,显著升高基质金属蛋白酶-9的表达。研究结果证实,中、高剂量...     

胆汁淤积性肝病治疗药物的临床研究进展

胆汁淤积性肝病是指由各种原因导致胆汁形成、分泌、排泄异常,从而引起肝脏发生病变.目前,治疗胆汁淤积性肝病的药物主要为熊去氧胆酸(UDCA),但近一半的患者对UDCA应答不充分或不耐受.这部分患者仅有奥贝胆酸(OCA)可用.随着近几年胆汁淤积性肝病的发病率明显上升,急需新型有效的治疗药物.临床研究表明,FXR激动剂、PP...     

聚砜膜生物反应器实验系统对重肝患者血浆的影响

目的：了解聚砜膜生物反应器实验系统对重肝患者血浆的影响,探索聚砜膜中空纤维反应器作为生物人工肝反应器的可行性。方法：用磁力搅动法将分离的新生实验小型猪肝细胞进行球形体培养,接种到聚砜膜中空纤维反应器外腔,观察聚砜膜生物反应器实验系统对重肝患者血浆的血氨、胆红素、凝血酶原时间、TNF-α、TGF-β1的影响。结果：该实验系统能降低重肝患者血浆的血氨、胆红素,缩短凝血酶原时间,降低TNF-α、TGF-β1水平。结论：聚砜膜生物反应器实验系统能够清除重肝患者血浆中的小分子有毒物质,补充有益成分,降低细胞因子水平。     

Male Rat Offspring Are More Impacted by Maternal Obesity Induced by Cafeteria Diet than Females—Additive Effect of Postweaning Diet

Maternal obesity increases the risk of health complications in offspring, but whether these effects are exacerbated by offspring exposure to unhealthy diets warrants further investigation. Female Sprague-Dawley rats were fed either standard chow (n = 15) or ‘cafeteria’ (Caf, n = 21) diets across pre-pregnancy, gestation, and lactation. Male and female offspring were weaned onto chow or Caf diet (2–3/sex/litter), forming four groups; behavioural and metabolic parameters were assessed. At weaning, offspring from Caf dams were smaller and lighter, but had more retroperitoneal (RP) fat, with a larger effect in males. Maternal Caf diet significantly increased relative expression of ACACA and Fasn in male and female weanling liver, but not CPT-1, SREBP and PGC1; PPARα was increased in males from Caf dams. Maternal obesity enhanced the impact of postweaning Caf exposure on adult body weight, RP fat, liver mass, and plasma leptin in males but not females. Offspring from Caf dams appeared to exhibit reduced anxiety-like behaviour on the elevated plus maze. Hepatic CPT-1 expression was reduced only in adult males from Caf fed dams. Post weaning Caf diet consumption did not alter liver gene expression in the adult offspring. Maternal obesity exacerbated the obesogenic phenotype produced by postweaning Caf diet in male, but not female offspring. Thus, the impact of maternal obesity on adiposity and liver gene expression appeared more marked in males. Our data underline the sex-specific detrimental effects of maternal obesity on offspring.     

The Deubiquitinase OTUB1 Is a Key Regulator of Energy Metabolism

Dysregulated energy metabolism is a major contributor to a multitude of pathologies, including obesity and diabetes. Understanding the regulation of metabolic homeostasis is of utmost importance for the identification of therapeutic targets for the treatment of metabolically driven diseases. We previously identified the deubiquitinase OTUB1 as substrate for the cellular oxygen sensor factor-inhibiting HIF (FIH) with regulatory effects on cellular energy metabolism, but the physiological relevance of OTUB1 is unclear. Here, we report that the induced global deletion of OTUB1 in adult mice (Otub1 iKO) elevated energy expenditure, reduced age-dependent body weight gain, facilitated blood glucose clearance and lowered basal plasma insulin levels. The respiratory exchange ratio was maintained, indicating an unaltered nutrient oxidation. In addition, Otub1 deletion in cells enhanced AKT activity, leading to a larger cell size, higher ATP levels and reduced AMPK phosphorylation. AKT is an integral part of insulin-mediated signaling and Otub1 iKO mice presented with increased AKT phosphorylation following acute insulin administration combined with insulin hypersensitivity. We conclude that OTUB1 is an important regulator of metabolic homeostasis.     

Oncogenic Mutation BRAF V600E Changes Phenotypic Behavior of THLE-2 Liver Cells through Alteration of Gene Expression

The accumulation of mutations in cancer driver genes, such as tumor suppressors or proto-oncogenes, affects cellular homeostasis. Disturbances in the mechanism controlling proliferation cause significant augmentation of cell growth and division due to the loss of sensitivity to the regulatory signals. Nowadays, an increasing number of cases of liver cancer are observed worldwide. Data provided by the International Cancer Genome Consortium (ICGC) have indicated many alterations within gene sequences, whose roles in tumor development are not well understood. A comprehensive analysis of liver cancer (virus-associated hepatocellular carcinoma) samples has identified new and rare mutations in B-Raf proto-oncogene (BRAF) in Japanese HCC patients, as well as BRAF V600E mutations in French HCC patients. However, their function in liver cancer has never been investigated. Here, using functional analysis and next generation sequencing, we demonstrate the tumorigenic effect of BRAF V600E on hepatocytes (THLE-2 cell line). Moreover, we identified genes such as BMP6, CXCL11, IL1B, TBX21, RSAD2, MMP10, and SERPIND1, which are possibly regulated by the BRAF V600E-mediated, mitogen-activated protein kinases/extracellular signal-regulated kinases (MAPK/ERK) signaling pathway. Through several functional assays, we demonstrate that BRAF L537M, D594A, and E648G mutations alone are not pathogenic in liver cancer. The investigation of genome mutations and the determination of their impact on cellular processes and functions is crucial to unraveling the molecular mechanisms of liver cancer development.     

外源质粒DNA对小鼠肝脏基因表达谱的影响

研究了外源质粒DNA经胃肠道吸收可能对肝脏产生的作用机制。给Balb／c小鼠灌胃质粒pcDNA3 200μg，在灌胃后4h分离肝脏，提取肝脏的总RNA。利用寡核苷酸芯片对灌胃质粒pcDNA3后的Balb／c小鼠肝脏进行基因表达谱研究。结果发现17664个基因中，表达上调100条，表达下调41条。按基因功能分类，表达上调的基因可分为免疫应答基因、转录因子基因、信号转导基因、转运相关基因及代谢相关基因等；表达下调的基因主要为脂质代谢基因。灌胃外源质粒DNA后，肝脏组织主要表现为急性时相反应的加强、免疫反应的活化、细胞信号通路的活化以及脂质代谢途径的抑制。表明外源质粒DNA通过胃肠道途径可广泛调控肝脏的基因表达。     

Performance comparison of free and immobilised chicken liver esterase inhibited by four different pesticides

BACKGROUND: In enzyme inhibition‐based biosensors for the detection of organophosphate and carbamate pesticides, the biological element is the immobilised esterase which is inhibited selectively by the pesticides. The free chicken liver esterase, which possesses comparable inhibition response to the pesticides as AChE, has been reported. However, the responses to the pesticides are different between the free and immobilised enzyme due to the diffusion limitation. Therefore, in this study four typical pesticides were selected to compare the ability of free and (ion exchange) immobilised chicken enzyme for pesticide detection and reasons for the difference were investigated. RESULTS: For dichlorvos and malathion at a concentration of 0.1 mg L^?1, the inhibition of the immobilised enzyme was 26.98% and 48.72%, respectively, higher than that for the free enzyme, while the percentage inhibition of free and immobilised enzyme differed very little for trichlorfon at 0.1 mg L^?1. In the meantime, carbaryl at a concentration of 2.5 mg L^?1 showed a 17.72% inhibition for immobilised enzyme which was 13.64% higher than that for the free enzyme. The Michaelis constant of immobilised enzyme was lower than that of the free one and suitable pH values for the free and immobilised enzyme were 7.5 and 8.0, respectively. CONCLUSIONS: The sensitivity of chicken liver esterase to the pesticide inhibition could be improved by immobilisation. Smaller K_m and a lower pH for the micro‐environment of immobilised enzyme should result in higher percentage inhibition compared with that of the free enzyme. Copyright © 2008 Society of Chemical Industry     

米糠甾醇对非酒精性脂肪性肝炎大鼠的治疗作用

目的：研究米糠植物甾醇对非酒精性脂肪性肝炎（non-alcoholic steatohepatitis,NASH）大鼠的干预治疗作用。方法：实验选用50只健康SD雄性大鼠,随机分为正常对照组、NASH模型组和米糠甾醇低、中、高3个剂量组（65、130、195 mg/kg）。高脂饲料饲喂造模,各实验组同时进行米糠甾醇溶液灌胃干预。13周后观察各组大鼠肝组织病理学特点,测定血清中血脂总胆固醇、甘油三酯、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇含量和谷丙转氨酶、谷草转氨酶、一氧化氮合酶和超氧化物歧化酶活性,并比较各组肝脏指数和脾脏指数。结果：肝脏组织切片观察到NASH模型组有明显的肝细胞脂肪变性和炎症聚集浸润,米糠甾醇各治疗组肝组织病变呈现不同程度减轻。NASH模型组血清高密度脂蛋白胆固醇含量、超氧化物歧化酶、一氧化氮合酶、谷丙转氨酶和谷草转氨酶活性与正常对照组相比,均表现出明显异常;米糠甾醇各剂量组与NASH模型组比较,血清谷丙转氨酶显著降低（P＜0.001）、谷草转氨酶/谷丙转氨酶比值显著升高（P＜0.01）;低剂量组血清超氧化物歧化酶（P＜0.05）和一氧化氮合酶（P＜0.001）显著降低;中剂量组血清高密度脂蛋白胆固醇显著升高（P＜0.05）。结论：米糠甾醇对大鼠非酒精性脂肪性肝炎有预防与治疗作用。     

嗜热链球菌grx02对酒精性肝损伤大鼠保护作用的分子机制

研究了嗜热链球菌grx02对急性酒精性肝损伤大鼠模型的保护作用机制。建立了急性酒精性肝损伤大鼠模型,观察嗜热链球菌grx02对急性酒精性肝损伤大鼠血清转氨酶以及炎症细胞因子的改善作用。结果表明,酒精可诱导大鼠血清谷氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、丙二醛(MDA)水平显著升高,;血清、肝匀浆中肿瘤坏死因子-α(TNF-α)、白介素-1β(IL-1β)、白介素-8(IL-8)细胞因子水平显著升高;乙醇脱氢酶(ADH)、还原性谷胱甘肽(GSH)、增加谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)活性显著下降,与对照组比较均有显著性差异。结论:grx02可能通过抑制炎性因子,增强抗氧化酶系活性、抑制氧化应激引发的肝损伤,对大鼠急性酒精性肝损伤发挥保护作用。