Steroid pulse therapy impaired endothelial function while increasing plasma high molecule adiponectin concentration in patients with IgA nephropathy.

BACKGROUND: Decreased plasma adiponectin is associated with impaired endothelial function and, thereby, increased risk for cardiovascular events. Glucocorticoid (GC) affects vascular endothelial cells either favourably or harmfully depending upon the dosages and duration. We examined the effect of GC pulse therapy on vascular endothelial function. METHODS: Fourteen young patients with IgA nephropathy were evaluated for flow-mediated vasodilation (FMD), plasma levels of adiponectin both in high molecular weight (HMW adiponectin) form and in single molecular form (total adiponectin), hepatocyte growth factor (HGF), asymmetric dimethylarginine (ADMA), and high-sensitive C-reactive protein, before and after a course of GC pulse therapy. RESULTS: GC pulse therapy significantly decreased FMD (from 7.2 +/- 2.6 to 5.7 +/- 2.5%, P < 0.01). Meanwhile, plasma adiponectin levels were significantly augmented (total adiponectin: from 10.2 +/- 4.0 to 12.1 +/- 6.3 microg/ml, P < 0.05; HMW: from 6.5 +/- 3.2 to 7.7 +/- 3.3 microg/ml, P < 0.05). In parallel, elevated concentrations of serum HGF (from 0.28 +/- 0.12 to 0.63 +/- 0.38 ng/ml, P < 0.01) and plasma ADMA (from 0.45 +/- 0.07 to 0.53 +/- 0.04 nmol/ml, P < 0.05) were observed. CONCLUSIONS: GC pulse therapy impaired endothelial function while increasing plasma adiponectin levels, which may in turn restore the endothelial function in patients with IgA nephropathy.     

柴胡及甘草酸对小鼠肝细胞凋亡的影响

目的：研究柴胡（ＲＢ）及甘草酸（ＧＬ）对小鼠肝细胞凋亡的影响。方法：以肝／体重比，肝组织ＤＮＡ含量，组织学改变及原位凋亡细胞ＴＵＮＥＬ反应为指标，观察ＲＢ（１２．０ｇ／ｋｇ）及ＧＬ（５０ｍｇ／ｋｇ）ｉｐ，１次／８ｈ，对撇除苯巴比胺钠（ＰＢ）后引起的小鼠肝细胞凋亡的影响。结果：与对照组Ｃ相比，ＲＢ组小鼠肝／体重比及肝ＤＮＡ含量无明显回落，组织学检查未见明显凋亡改变，ＴＵＮＥＬ反应阴性，ＧＬ组小鼠肝／     

A rapid and sensitive method for measuring monooxygenase activities in hepatocytes cultured in 96-well plates

Summary Measurement of biotransformation activities in cells is of great importance for drug metabolism and toxicologic studies. It is currently done by measuring the enzymatic activities in partially purified microsomes. In the present work we report on a rapid, easy, sensitive, and reproducible fluorimetric assay for quantifying cytochrome P450-dependent monooxygenase activities (P450IA1, P450IIB1) in hepatocytes cultured in 96-well plates. The procedure involves the direct determination of enzymatic activities in intact hepatocytes while avoiding cell homogenization, thereby permitting use of a the reduced number of cells and allowing cultured cells to be used in later experiments. Substrates (7-ethoxyresorufin, 7-pentoxyresorufin) are added to culture medium and metabolized by hepatocytes. After enzymatic deconjugation, the fluorescent resorufin present in culture medium is quantified by means of a microplate fluorimetric reader. Major advantages of this technique, as compared to other available methods, are: a) no cell disruption is required; b) activity can be measured with a very small number of cells; c) rapid processing time; and d) possibility of performing repeated assays with the same cell monolayer.     

Liver regeneration in acute severe liver impairment: a clinicopathological correlation study.

BACKGROUND: Although normally quiescent, the adult mammalian liver possesses a great capacity to regenerate after different types of injury. Major players in the regeneration process are mature residual cells, including hepatocytes, cholangiocytes and stromal cells. However, if the regenerative capacity of mature cells is impaired, hepatic progenitor cells (HPCs) are activated and expand into the liver parenchyma. Upon transit amplification, the progenitor cells generate new hepatocytes and biliary cells to restore liver homeostasis. AIMS/METHODS: To study the relationship between different histopathological parameters as well as their correlations with clinical parameters and outcome, we examined liver specimens from 74 patients with acute or subacute severe liver impairment by immunohistochemistry for CK7/CK19 (evaluation of HPCs activation/differentiation), Mib1(Ki 67)/P21 (evaluation of proliferative activity/proliferation arrest of hepatocytes) and hematoxylin and eosin (evaluation of hepatocyte loss). RESULTS: Of the 74 patients, 32% survived without transplantation, 14% died without transplantation and 54% were transplanted. Our results show that a threshold of 50% loss of hepatocytes, associated with significant decrease in the proliferative activity of remaining mature hepatocytes, is needed for extensive hepatic progenitor cell activation. Such activation is a sign of disease severity and occurs early (within 1 week) in the disease course. However, development of intermediate hepatocytes, suggesting HPCs differentiation towards mature hepatocytes, takes at least 1 week's time. We found a positive correlation between histopathological parameters (percentage hepatocyte loss, number of proliferating hepatocytes and number of HPCs) and clinical parameters of liver impairment such as model for end stage liver diseases (MELD). Surviving patients compared with those who either died or were transplanted had significantly less hepatocyte loss, less HPCs activation and more mature hepatocyte proliferative activity. Hepatocyte proliferative activity and degree of hepatocyte loss were the most important independent histopathological parameters in predicting outcome. CONCLUSION: Liver biopsy can provide important additional information in a patient with severe acute liver impairment.     

次声90 dB和130 dB致大鼠肝细胞损伤的超微结构改变

目的：探讨相同频率(16 Hz)不同声压水平(90 dB与130 dB)次声作用下大鼠肝细胞超微结构损伤特点及意义．方法：将雄性SD大鼠66只，随机分为对照组(6只)、实验1(90 dB)和实验2(130 dB)组．根据次声作用时间，实验1，2组各分为1，7，14，21和28 d时间组，每组6只．在相同频率不同声压水平次声环境下每日暴露1次，每次2 h；取肝左右叶两个部位组织用戊二醛和锇酸固定，透射电镜下观察肝超微结构变化．结果：1 d组：90 dB环境作用下肝超微结构无明显损伤变化，130 dB环境作用下肝细胞内有脂滴出现；7，14和21 d组不同环境和天数次声作用后肝损伤出现脂滴逐渐增多和肝细胞部分变性坏死改变，发现肝细胞内的各种结构随次声作用次数增多其损伤程度逐渐加重；28 d组其损伤程度均有一定程度恢复．结论：次声下可以对肝细胞超微结构造成不同程度损伤，28 d后肝细胞对次声的损伤作用存在着一定适应现象．     

小鼠肝癌细胞H22对淋巴内皮细胞flt-4、c-fos、PCNA表达的影响

目的：初步探讨有自发淋巴转移特性的肝癌细胞对淋巴内皮细胞增殖的影响。方法：弗氏不完全佐剂诱导Balb／c小鼠腹腔良性淋巴管瘤，分离瘤体消化法体外培养淋巴内皮细胞；H22细胞接种Balb／c小鼠腹腔，收集腹水制成H22条件培养液，观察其对淋巴内皮细胞生长和表达flt-4、c-fos、PCNA的影响。结果：小鼠淋巴管瘤来源的淋巴内皮细胞可成单层贴壁培养，在内皮细胞完全培养液和H22条件培养液作用下可增殖达到或接近铺满状态，并阳性表达flt-4、c-fos、PCNA，普通培养液不能支持细胞生长，flt-4等染色为阴性：结论：淋巴内皮细胞增殖可能是癌细胞淋巴路转移的必要条件。     

介绍一种大鼠肝细胞的分离和培养方法

介绍分离、纯化大鼠肝细胞(用胶元酶二步灌流和PercoⅡ不连续密度离心)及分离后的培养。此方法可靠易行，可制备出质量合格的肝细胞(实质细胞)。讨论了保证分离和纯化成功的一些关键步骤、条件和原理．提出分离肝细胞应首选胶元酶Ⅳ，PereoⅡ的渗透压和pH也是影响肝细胞的漂浮密度和存活能力的因素。     

Design-based stereological estimation of hepatocyte number, by combining the smooth optical fractionator and immunocytochemistry with anti-carcinoembryonic antigen polyclonal antibodies.

BACKGROUND/AIMS: Hepatocytes (HEP) have been the major target for structural quantification in the liver, but an estimation of their total number (N), their percentage in relation to the global number of liver cells and the evaluation of the percentage of binucleated hepatocytes (BnHEPs) have never been performed with modern design-based stereological techniques. The establishment of sound technical guidelines and baseline quantitative data in non-pathological conditions are relevant to properly evaluate HEP hyperplasia and BnHEP responses. METHODS: In this study, we combined immunocytochemistry with sound design-based stereology for estimating the N of HEP and the N of non-hepatocytic cells (NHCs). For obtaining systematic uniform random sections (30 microm thick), a smooth fractionator sampling scheme was applied to the liver of five male Wistar rats (3 month old). Those sections were immunostained with polyclonal antibodies against carcinoembryonic antigen. Because biliary canaliculi were then marked, an unequivocal counting of mononucleated hepatocytes (MnHEP) and BnHEP was allowed. RESULTS: The N of HEP was estimated to be 1.93 x 10(9), with a coefficient of error (CE) of 0.02, corresponding to 129 x 10(6) HEP/g of liver. BnHEP represented 26% of total HEP number. The N of NHC was estimated as 1.31 x 10(9) (CE=0.02). CONCLUSION: The strategy here presented provides a reliable method for accessing the N of HEP (distinguishing MnHEP from BnHEP) in situations in which these parameters are relevant, namely for evaluating the magnitude of an hyperplastic liver response from its very early onset.