Hepatocyte Lesions Research Articles

Життєстійкість та рівень якості життя пацієнтів з НАЖХП: пілотне дослідження

Background. The prevalence of NAFLD in the general population is approximately 20-30% in Western countries and 5-18% in Asia. NAFLD consists of a range of liver diseases, ranging from simple deposition of fat in the liver (steatosis; called nonalcoholic fatty liver or NAFLD) to steatosis with associated hepatocyte lesions (NASH). Importantly, NASH, in turn, can lead to fibrosis, cirrhosis, and, in some cases, hepatocellular carcinoma (HCC). The aim of the study. The purpose of the study: to increase the effectiveness of treatment of patients with non-alcoholic fatty liver disease by optimizing lifestyle with psycho-corrective effects. Research methods. The study is conducted based on the gastroenterology department of the Center for Innovative Medical Technologies of the National Academy of Sciences of Ukraine. As of September 2021, a total of 23 patients with the non-alcoholic fatty liver disease aged 37 to 58 years (mean age 46.5 years) were examined, including 11 men (47.8%) and 12 women (52.2%). The initial survey and testing of patients are carried out on days 1-3 of admission to the hospital. The following methods were used in the study: "10 words" by AR Luria, Schulte tables, SRRS (Holmes and Ray scale), S. Muddy's vitality questionnaire, modified by D.A. Leontieva, SF-36 (Medical Outcomes Study Short Form). Results. In all interviewed patients, the level of cognitive functioning was at a satisfactory level. The level of both the actual viability and its subscale in most respondents was within the average. All respondents, without exception, had a moderate risk of developing the disease due to life events, which is of some concern. However, further research is likely to provide more information and an opportunity to confirm or refute the hypothesis formed at this stage of the study. According to the results of the assessment of the quality of life of patients, slightly less than half of the respondents (47.8%) have a reduced level of quality of life. Conclusions. The results presented in the article are another confirmation of the relevance and necessity of research aimed at identifying influencing factors and means to improve quality of life and the formation of a healthy internal picture of the disease of patients with non-alcoholic fatty liver disease.

\u03b1-Fetoprotein mRNA in situ hybridisation is a highly specific marker of hepatocellular carcinoma: a multi-centre study

BackgroundPathologic diagnosis of hepatocellular carcinoma (HCC) can be challenging in differentiating from benign and non-hepatocytic malignancy lesions. The aim of this study was to investigate the potential utility of α-fetoprotein (AFP) mRNA RNAscope, a sensitive and specific method, in the diagnosis of HCC.MethodsThree independent retrospective cohorts containing 2216 patients with HCC, benign liver lesions, and non-hepatocytic tumours were examined. AFP was detected using ELISA, IHC (Immunohistochemistry), and RNAscope. Glypican3 (GPC3), hepatocyte paraffin-1 (HepPar-1), and arginase-1 (Arg-1) proteins were detected using IHC.ResultsAFP RNAscope improved the HCC detection sensitivity by 24.7–32.7% compared with IHC. In two surgical cohorts, a panel of AFP RNAscope and GPC3 provided the best diagnostic value in differentiating HCC from benign hepatocytic lesions (AUC = 0.905 and 0.811), and a panel including AFP RNAscope, GPC3, HepPar-1, and Arg-1 yielded the best AUC (0.971 and 0.977) when distinguishing HCC from non-hepatocytic malignancies. The results from the liver biopsy cohort were similar, and additional application of AFP RNAscope improved the sensitivity by 18% when distinguishing HCC from benign hepatocytic lesions.ConclusionsAFP mRNA detected by RNAscope is highly specific for hepatocytic malignancy and may serve as a novel diagnostic biomarker for HCC.

Stellate cells in livers of dogs with portal vein hypoperfusion

Hepatic stellate cells play a crucial role in the development of liver fibrosis. In a damaged liver, stellate cells undergo activation, which is manifested as a change of their phenotype: differentiation of stellate cells to myofibroblast-type cells, expression of alpha-Smooth Muscle Actin, their proliferation and a reduction in the size of cytoplasmic lipid droplets. The aim of this study was to determine the number and morphology of stellate cells in the canine liver affected by congenital portosystemic shunt (PSS) and portal vein hypoplasia – hepatic microvascular dysplasia (PVH-HMD). The material for investigation were archived paraffin blocks with liver samples collected supravitally from six dogs with PSS, six dogs with PVH-HMD and six healthy dogs. On the HE-stained sections, the number of stellate cells per 100 hepatocytes was counted (Sztark method) and the diameter of veins in the hepatic triads was measured (light microscope Olympus BX 43, SC30 camera, CellSens Entry 2011 Olympus). In addition, the diameter of lipid droplets in stellate cells was measured (computed image analysis system LUCIA 4.21). The results were analysed statistically (the Kruskal-Wallis test followed by Dunn’s post-hoc procedure; significance level (α) at 0.05; Statistica 12 StatSoft Inc.). The degree of liver fibrosis was determined (Masson’s method of slide stain; Scheuer scale). The liver samples from the dogs with PSS and PVH-HMD were stained immunohistochemically with Monoclonal Mouse Anti-Human Smooth Muscle Actin (α-SMA), clone 1A4, antibodies (DAKO). Portosystemic shunt and primary portal vein hypoplasia in the dog results in a reduction in the diameter of portal vein branches and in insufficient portal blood flow through the liver. In the material investigated, this was particularly evident in the animals affected by PSS: such dogs had a significantly smaller diameter of the veins than did the healthy dogs (p<0.001) or the dogs with PVH-HMD (p=0.023). Fibrosis and the expression of α-SMA were stronger in the dogs with PSS than in those with PVH-HMD. Moreover, the dogs with PSS had a significantly higher average number of stellate cells than the healthy animals (p=0.007) did. However, the examination of the material revealed an enlargement of cytoplasmic lipid droplets: the dogs with PSS had a significantly larger diameter of lipid vacuoles in the cytoplasm of stellate cells than did the healthy animals (p<0.001) or the dogs with PVH-HMD (p=0.043); the dogs with PVH-HMD had lipid droplets with a significantly larger diameter than the healthy animals (p<0.001) did. Hypoperfusion of the liver and the accompanying regressive lesions in hepatocytes result mainly in an increased number of stellate cells and stronger expression of α-SMA, while cytoplasmic lipid droplets in the stellate cells are not reduced in size. The present study indicates the need for detailed analyses of clinical cases and warrants further comprehensive studies of comparative hepatopathology because it demonstrates differences between humans and dogs in the morphological indicators of hepatic stellate cell activation in chronic liver damage.

A practical diagnostic approach to hepatic masses.

The differential diagnosis of hepatic mass lesions is broad and arriving at the right diagnosis can be challenging, especially on needle biopsies. The differential diagnosis of liver tumors in children is different from adults and is beyond the scope of this review. In adults, the approach varies depending on the age, gender, and presence of background liver disease. The lesions can be divided broadly into primary and metastatic (secondary), and the primary lesions can be further divided into those of hepatocellular origin and nonhepatocellular origin. The first category consists of benign and malignant lesions arising from hepatocytes, while the second category includes biliary, mesenchymal, hematopoietic, and vascular tumors. Discussion of nonepithelial neoplasms is beyond the scope of this review. The hepatocytic lesions comprise dysplastic nodules, focal nodular hyperplasia, hepatic adenoma, and hepatocellular carcinoma, and the differential diagnosis can be challenging requiring clinicopathological correlation and application of immunohistochemical (IHC) markers. Liver is a common site for metastasis, sometimes presenting with an unknown primary site, and proper workup is the key to arriving at the correct diagnosis. The correct diagnosis in this setting requires a systematic approach with attention to histologic features, imaging findings, clinical presentation, and judicious use of IHC markers. The list of antibodies that can be used for this purpose keeps on growing continually. It is important for pathologists to be up to date with the sensitivity and specificity of these markers and their diagnostic role and clinical implications. The purpose of this review is to outline the differential diagnosis of hepatic masses in adults and discuss an algorithmic approach to make a right diagnosis.

Метаболическая активность культуральной жидкости ксеногенных, аллогенных гепатоцитов и фибробластов в условиях экспериментального острого тетрахлорметанового поражения печени

The development of basic biochemical syndromes of liver damage (cytolysis, intrahepatic and extrahepatic cholestasis, intracellular cholestasis with jaundice and toxic lesions of hepatocytes, insufficient synthetic processes, insufficiency inflammation) and activation of free radical oxidation at systemic and local (erythrocytes) levels was established in experimental acute toxic tetrachlormetan liver damage. Humoral factors of culture fluid of fetal hepatocytes in allogeneic recipients with acute toxic hepatopathy correct the systemic and local metabolic disorders arising due to hepatotropic poison exposure more effectively as compared to culture fluid of xenogeneic hepatocytes and fibroblasts.

Cytokeratin-19 positivity is acquired along cancer progression and does not predict cell origin in rat hepatocarcinogenesis.

Although the expression of the stem/progenitor cell marker cytokeratin-19 (CK-19) has been associated with the worst clinical prognosis among all HCC subclasses, it is yet unknown whether its presence in HCC is the result of clonal expansion of hepatic progenitor cells (HPCs) or of de-differentiation of mature hepatocytes towards a progenitor-like cell phenotype. We addressed this question by using two rat models of hepatocarcinogenesis: the Resistant-Hepatocyte (R-H) and the Choline-methionine deficient (CMD) models. Our data indicate that the expression of CK-19 is not the result of a clonal expansion of HPCs (oval cells in rodents), but rather of a further step of preneoplastic hepatocytes towards a less differentiated phenotype and a more aggressive behavior. Indeed, although HCCs were positive for CK-19, very early preneoplastic foci (EPFs) were completely negative for this marker. While a few weeks later the vast majority of preneoplastic nodules remained CK-19 negative, a minority became positive, suggesting that CK-19 expression is the result of de-differentiation of a subset of EPFs, rather than a marker of stem/progenitor cells. Moreover, the gene expression profile of CK-19-negative EPFs clustered together with CK-19-positive nodules, but was clearly distinct from CK-19 negative nodules and oval cells. i) CK-19-positive cells are not involved in the early clonal expansion observed in rat hepatocarcinogenesis; ii) CK-19 expression arises in preneoplastic hepatocyte lesions undergoing malignant transformation; iii) CK-19 positivity in HCCs does not necessarily reflect the cell of origin of the tumor, but rather the plasticity of preneoplastic cells during the tumorigenic process.

The preventive effect of cooked and germinated legumes on some disturbances accompanied with aging

Legume consumption may play an important role on the health life during aging through its well-recognized antioxidant, antiproliferative, and antigenotoxic effects. The present study aimed to clarify the effect of some legumes feeding on oxidative stress in menopause rats. The experiment was carried out on 66 female rats (16-17 months old) divided into 11 groups. The first group was fed basal diet and kept as control group. The remaining groups were fed basal diet containing 20 % of different processed legumes either cooked or germinated (faba bean, chickpea, lentil, white bean and fenugreek). The experiment continued for 8 weeks .Growth of rats, biochemical analyses and histopathological examination were evaluated. Results showed that the body weight changed from the highest percentage of decrease (-7.7%) in the group fed on diet including germinated white bean and the highest percentage of increase (+7.1%) in the group fed cooked lentil supplemented diet. The study also demonstrated improvement in lipid profile, particularly in VLDL-C and triglycerides levels. The highest percentage decreases of atherogenic index relative to control group were 46.5, 44 and 40% in groups supplemented with germinated lentil, cooked faba bean and germinated faba bean, respectively. Germination process is more effective than cooking treatment by enhancing the antioxidant enzymes such as SOD and GPx, also by reducing liver enzymes like, alkaline phosphatase and aspartate transferase, particularly germinated lentil group and decreasing lipid peroxidation reflected on histopathological lesions in hepatocytes. Moreover, serum protein was higher in germinated legumes diets than cooked ones. In conclusion, the obtained results suggest that diets containing legumes, particularly the germinated form exert a beneficial effect in reducing some disturbances associated with aging.

Effects of natural compounds in treatment and prevention of hepatotoxicity and hepatocellular carcinoma

Liver diseases are most common disorders in the world and characterized by rapid changes from steatosis to chronic hepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Natural products that attained great attention is to be used in the prevention and treatment of multiple diseases in humans. Several researches have been reported numerous natural and phytochemical compounds that may counteract or prevent the hepatic injury and primary liver cancer. The conservative treatment of liver toxicity and HCC may face awkward challenges in chemotherapy such as therapeutic failure or drug resistance. Accordingly, there is an actual need for safe and effective therapeutic and preventive modalities for liver disorders. The present review aims to focus on the potential protective and therapeutic effects of natural compounds in the prevention and treatment of hepatotoxicity and HCC. It also demonstrates the mechanism of the natural products in enzymatic regulation of antioxidants and its role in apoptosis and proliferation of cancerous lesions of hepatocytes. Accordingly, it highlights the promising role of natural bioactive compounds and provides the rational for further transitional researches, and emphasize on the scientific validation of natural compounds for therapeutic portfolio for clinical use in liver diseases.

Histopathological effects of Methotrexate in mice livers

Background:Methotrexate is a folic acid antagonists that inhibits dihydrofolate reductase, resulting in a block in the synthesis of thymidine and inhibition of DNA synthesis. Methotrexate has been used for the treatment of malignancy, rheumatic disorders, and psoriasis and termination of intrauterine pregnancy. Recently, methotrexate has become a standard treatment for ectopic pregnancy. However, the use of methotrexate is limited due to high incidence of serious dose-dependent toxicity of methotrexate, including hepatotoxicity, renal damage, bone marrow suppression and gastrointestinal mucosal inflammation . Objective:Evaluate the effect of the treatment with multiple doses of methotrexate in the livers of mice. Materials &Methods: A total of (70) white mice at the ages of (4-8 weeks) and body weight of about (25+2 gm) were used in the study. Mice were divided into seven groups where each group received multiple doses of (0.05mg/Kg) of methotrexate during an interval of six weeks where the animals of each group had injected with a single dose of(0.05mg/Kg) of methotrexate at the beginning of each week and then, they were killed and autopsied after five days. On the other hand, the control group had received (0.1ml) of normal saline. Liver slide sections were examined by light microscope and photographed. Then, images were assessed histopathologically and comparisons were made between mice groups received different doses of methotrexate. Results: Results showed that, a single dose of (0.05mg/kg) of methotrexate produced no liver tissue histopathological effects on the liver of the treated mice. While, six weeks of methotrexate treatment produced significant changes in the liver of the treated mice including lymphocyte infiltration, necrosis, liver tissue fatty degeneration and congestion and dalitation of the hepatic vein. Conclusions: It was concluded that, a single dose of (0.05mg/Kg) of methotrexate had no effect on mice liver histology. While, multiple doses of methotrexate were associated with significant side effects included a hallmark of cellular infiltration and lesions of necrotic hepatocytes with congestion and dalitation of hepatic vein. Thus, the administration of multiple doses of methotrexate for the treatment of various medical conditions should be considered carefully to avoid liver damage of the patient especially in the case of ectopic pregnancy.

Hepatic stellate cells in the liver of dogs with steroid-induced hepatopathy

Abstract Morphological lesions in hepatic stellate cells caused by the immunosuppressive doses of dexamethasone were investigated in dogs. The archival samples of liver collected during a surgical biopsy were examined. The samples were fixed in 10% buffered formalin or Carnoy’s solution and then stained with routine histochemical methods. The lesions were also investigated under electron microscope. It was demonstrated that the number of stellate cells significantly increased (P = 0.0277), yet the size of cytoplasmic lipid droplets significantly decreased (P = 0.0001). Even though steroid-induced hepatopathy is considered to be a reversible pathology, and the lesions in hepatocytes under the influence of dexamethasone occur in a short period, it was found that hepatic stellate cells proliferated and underwent activation. This resulted in collagen accumulation in the hepatic sinuses. The functional and morphological disturbances in the canine liver in the course of steroid-induced hepatopathy are initially subclinical, but the changes in the structure and function of hepatic stellate cells may become a cause of lesions in the wall of hepatic sinusoidal vessels, which may induce additional functional pathologies unrelated to the damage to hepatocytes.

Effects of subchronic exposure to atrazine on zebrafish (Danio rerio)

The aim of this study was to investigate the effects of subchronic exposure to atrazine on fish growth and the development of histopathological changes in selected organs (gill, kidney, liver) in Danio rerio. Juvenile growth tests were performed on D. rerio according to OECD method No. 215. For 28 days, fish at an initial age of 30 days were exposed to the environmental atrazine concentration commonly detected in Czech rivers (0.3 microg/L) and a range of sublethal concentrations of atrazine (3.0, 30.0 and 90.0 microg/L). The results showed decreasing growth rates and morphological changes in the liver (dystrophic lesions of hepatocytes) at 90.0 microg/L of atrazine. The environmental concentration of atrazine in Czech rivers did not have any effect on fish growth and development of histopathological changes in D. rerio. The value of NOEC was 30.0 microg/L and the value of LOEC was 90.0 microg/L.

Comparative histomorphological review of rat and human hepatocellular proliferative lesions.

In this comparative review, histomorphological features of common nonneoplastic and neoplastic hepatocyte lesions of rats and humans are examined using H&E-stained slides. The morphological similarities and differences of both neoplastic (hepatocellular carcinoma and hepatocellular adenoma) and presumptive preneoplastic lesions (large and small cell change in humans and foci of cellular alteration in rats) are presented and discussed. There are major similarities in the diagnostic features, growth patterns and behavior of both rat and human hepatocellular proliferative lesions and in the process of hepatocarcinogenesis. Further study of presumptive preneoplastic lesions in humans and rats should help to further define their role in progression to hepatocellular neoplasia in both species.

Metabolism of cyclic GMP in non-alcoholic fatty liver disease in morbid obesity

Methods Patients: MO group: 48 patients (40 women and 8 men) diagnosed of MO with an age of 46.9± 7.9. Control group: 19 subjects without overweight and with normal analytical data and normal ultrasound scan of the liver. The following parameters were measured: A.Clinical data: Age, sex, weight, height, abdominal and hip perimeters, Body Mass Index (BMI), clinical history and pharmacological treatment, Metabolic Syndrome, morfometry and haematic chemistry, Insulin Resistance (HOMA) and viral markers. B Immunomodulators: (Leptin, Adiponectin, CK18Asp396 (CK18), Interleukin-6 (IL-6), aldosterone and rennin). C Histological analysis was performed after obtaining hepatic tissue during surgery for MO. The NAFLD Score was calculated: Steatosis Degree, Fibrosis, Inflammation, hepatocyte lesions and other injuries).

Abstract LB-427: Unique properties of hepatocarcinogenesis-resistant DRH rat hepatocytes linked or not linked to the Drh1 locus on rat chromosome 1

Abstract DRH rats were established by the selective mating of Donryu rat progeny that exhibited resistance to hepatocarcinogenesis. DRH rats show smaller and fewer preneoplastic hepatocytic lesions than ordinary rats after treatment with hepatocarcinogenic regimens, and these traits have been assigned to two major genetic loci, Drh1 on chromosome 1 and Drh2 on chromosome 4. The DRH hepatocytes have the unique properties such as low proliferation after lead nitrate (LN) treatment, resistance to hepatotoxic chemicals and small cell size. If some of these properties are linked to the Drh1 or Drh2 loci, the properties may be related to the mechanism(s) of the hepatocarcinogenesis-resistance in DRH rats. In this study, to explore what properties are linked to the Drh1 locus, we compared hepatocytes of DRH.F344-Drh1 rats, a congenic DRH strain in which the DRH chromosomal region including the Drh1 locus was substituted by that of F344 rats, were compared with hepatocytes of Donryu, DRH and F344 rats. After LN treatment, although DRH hepatocytes proliferated at low rate, DRH.F344-Drh1 hepatocytes proliferated at high rate comparable to Donryu and F344 hepatocytes. In addition, the DRH.F344-Drh1 livers showed high p38 MAPK dephosphorylation after LN treatment like Donryu and F344 livers, while such p38 MAPK dephosphrylation was not seen in the DRH liver. However, increase of TNF-α, IL-6 and Cox2 mRNA and NFκB/Stat3 activation in the liver was almost at the same degree in Donryu, DRH and DRH.F344-Drh1 rats, suggesting that the low responses to LN in the DRH hepatocytes were not dependent on low cytokine/Cox2 activation but rather due to the inherent properties of DRH hepatocytes. After 200 mg/Kg diethylnitrosamine (DEN) or 5 ml/Kg CCl4 treatment, severe hepatic injury occurred in DRH.F344-Drh-1 rats like Donryu and F344 rats, while its degree was much less in DRH. On the other hand, the DRH.F344-Drh1 as well as DRH hepatocytes exhibited lower proliferation after the EGF or HGF treatment in vitro than Donryu and F344 hepatocytes. Furthermore, the nuclear size of DRH.F344-Drh1 hepatocytes was comparable to that of DRH hepatocytes, which was smaller than those of Donryu and F344 hepatocytes. These findings indicate that the Drh1 locus is linked to the low responses to LN and hepatotoxin resistance in DRH hepatocytes, but not to low proliferation in vitro and small nuclear size. (Supported by the grants from the Japanese Ministry of Education, Science, Culture and Sports.) Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr LB-427. doi:10.1158/1538-7445.AM2011-LB-427

Ex vivo assessment of protective effects of carvacrol against DNA lesions induced in primary rat cells by visible light excited methylene blue (VL+MB)

Carvacrol belongs to frequently occurring phenolic components of essential oils (EOs) and it is present in many kinds of plants. Biological effect of this phenol derivative on human beings is however not sufficiently known. The present study was undertaken to evaluate the level of VL+MB-induced oxidative DNA lesions in hepatocytes and testicular cells (freshly isolated from control or carvacrol-watered rats) by the modified single cell gel electrophoresis (SCGE). The results showed that carvacrol significantly reduced the level of VL+MB-induced oxidized bases (EndoIII- and Fpg-sensitive sites) only in hepatocytes but not in testicular cells. Chromosomal aberration assay of primary hepatocytes, isolated from control or carvacrol-watered rats did not testify any genotoxic activity of carvacrol. We suggest that in vivo applied synthetic carvacrol, whose antioxidative activity was confirmed by DPPH assay, exhibits primarily a strong hepatoprotective activity against oxidative damage to DNA.

Unique Properties of Hepatocarcinogenesis-Resistant DRH Rat Hepatocytes Linked or Not Linked to theDrh1Locus on Rat Chromosome 1

Hepatocarcinogenesis-resistant DRH rats exhibit few and small preneoplastic hepatocytic lesions during hepatocarcinogenesis, of which traits have been assigned to two major chromosomal regions, Drh1 and Drh2. In this study, hepatocytes from DRH.F344-Drh1, a congenic strain in which the Drh1 chromosomal region was replaced with that of F344 rats, were compared to hepatocytes from Donryu (original strain), DRH, and F344 rats. Although DRH hepatocytes exhibited low proliferation and p38 dephosphorylation after lead nitrate (LN) treatment despite cytokine and Cox2 activation, DRH.F344-Drh1 hepatocytes exhibited high responses, as did Donryu and F344 hepatocytes. Moreover, although DRH hepatocytes were resistant to hepatotoxins, DRH.F344-Drh1 hepatocytes were as sensitive to hepatotoxins as Donryu and F344 hepatocytes. However, DRH.F344-Drh1 hepatocytes like DRH hepatocytes proliferated at lower rates in vitro and contained smaller nuclei than Donryu and F344 hepatocytes. Thus, low responses to LN and resistance to hepatotoxins in DRH hepatocytes were linked to the Drh1 locus, while low proliferation in vitro and small nuclear size were not linked to the Drh1 locus.

The reduction of glycogen in the liver induced by chronic intravenous heroin abuse

Introduction. The liver plays a key role in the removal of lipophyllic substances from the plasma, including both morphine and its derivative heroin. Intravenous heroin abuse leads to liver damages, so that the effects of heroin intake are the most marked and characteristic in the liver. Objective. A histochemical and ultrastructural study of the liver, particularly hepatocyte glycogen content, should provide a precise insight into the type and degree of liver damage induced by intravenous heroin abuse. Methods. The study included the analysis of 50 autopsies, 40 from the group of intravenous heroin abusers and 10 control autopsies. Paraffin sections, 5 µm thick, were stained by PAS method for deposited glycogen staining. The ultrastructural investigation was performed on transmission electron microscope. Results. Glycogen amount was reduced proportionally to the severity and distribution of degenerative and necrotic hepatocytic lesions. Regarding deposited glycogen depletion in particular acinar zones, glycogen was most preserved in zone 1 (30% of studied cases), then in zone 3 (preserved in 25%), while the depletion was most significant in intermediary zone (preserved in 5%). In the intravenous heroin abusers group of up to 2 years glycogen was preserved in the acinar zones 1, 2 and 3 in 43%, 30% and 57%, respectively; in the group of over 10 years glycogen preservation in zone 1 was 25% and in other zones 0%. Conclusion. Intravenously administered heroin directly influences glycogen reduction in the hepatocytes, and the effect is potentiated by morphologic changes in the liver due to intravenous heroin abuse. Glycogen depletion in the hepatocytes reduces energy reserves in these cells and causes cell death, which is an important segment of general liver injury in intravenous heroin abusers. The degree of reduction of glycogen depositions is proportional to the duration of intravenous heroin abuse

Tumor promoting and co-carcinogenic effects in medium-term rat hepatocarcinogenesis are not modified by co-administration of 12 pesticides in mixture at acceptable daily intake

The purpose of this investigation was to evaluate the possible influence of a mixture of pesticides on medium-term carcinogenesis using improved hepatocarcinogenesis protocols. We performed a 12 commercially available pesticides combination with alachlor, atrazine, carbofuran, chlorpyrifos, diazinon, dicofol, endosulfan, iprodione, mancozeb, maneb, procymidone and rotenone. The mixture was given at 1-fold and 10-fold the acceptable daily intake (ADI) level in a set of Solt–Farber-derived protocols involving diethylnitrosamine, 2-acetylaminofluorene treatments and a partial hepatectomy. Co-carcinogenic effect and promoting activity were evaluated using γ-glutamyl transpeptidase (GGT) positive altered hepatocyte foci, as well, protein and mRNA levels of glutathione S-transferase P (GSTP) in liver extracts as molecular biomarkers of carcinogenic effects. The pesticide treatments when compared to vehicle treatments always produced the same number of hepatocyte lesions and an equal GSTP expression on liver extracts independently of carcinogenic-protocol utilized. On this base, we concluded that the pesticide mixture evaluated in this report does not have tumor promoting activity or co-carcinogenic effect in the rat medium-term liver carcinogenesis. Altogether these data contribute to the confidence that the ADI represents a safe intake level to mixture of pesticides at dietary exposure.

Alteration of adhesion molecule expression and cellular polarity in hepatocellular carcinoma

To study the expression of adhesion molecules in human liver and their possible roles during hepatocarcinogenesis. The expression of adhesion molecules in normal liver tissues, benign including probable premalignant lesions and malignant lesions was systematically investigated by immunohistochemistry and Western blotting. In normal liver, both hepatocytes and bile duct cells expressed symplekin, desmoglein 1/2, desmocollin 2, desmoplakin and plakophilin 2, but did not express desmocollin 1/3 or plakophilin 1. In benign hepatocyte lesions, expression of the adherens junctions and desmosomes was uniform and slightly increased, but symplekin appeared to show reduced expression in dysplastic lesions. In hepatocellular carcinoma (HCC), the expression of adhesion molecules was often heterogeneous and of abnormal location. Tumour cells with an abnormal distribution or loss of adhesion molecules showed an apolar arrangement of tissue architecture. The expression levels of the adhesion molecules correlated with the differentiation grades of HCC cells. The decreased expression of symplekin may be an early step in the transformation of hepatocytes, whereas alteration of the expression of adherens junctions and desmosomes may indicate more serious changes.

The Expression of Transforming Growth Factor-α in Cirrhosis, Dysplastic Nodules, and Hepatocellular Carcinoma

The emergence of hepatocellular carcinoma (HCC) is thought to be a stepwise process, with high-grade dysplastic nodules (HGDN) representing premalignant lesions arising in a background of cirrhosis. Earlier studies have revealed altered expression of transforming growth factor-alpha (TGF-alpha) (a mitogen capable of inducing hepatocarcinogenesis in mice) in HCC and its surrounding parenchyma. DNA topoisomerase II-alpha (Topo II-alpha) is a nuclear protein targeted by several chemotherapeutic agents and is overexpressed in HCC. The expression of both TGF-alpha and Topo II-alpha in putative preneoplastic hepatocytic lesions, however, has not been extensively studied. We examined the patterns of TGF-alpha and Topo II-alpha expression in noncirrhotic liver, liver cirrhosis, low-grade dysplastic nodules (LGDN), HGDN, and HCC to define the possible relationships of these markers to tumor progression. Paraffin sections from formalin-fixed material were immunostained with antibodies against TGF-alpha, Topo II-alpha, and Ki-67. Forty-six HCC, 17 HGDN, and 12 low-grade dysplastic nodules were identified in 52 cirrhotic livers from explanted or resected specimens. Nuclear staining for Ki-67 and Topo II-alpha was significantly increased in the progression from cirrhosis, through HGDN, to HCC, whereas the scores for TGF-alpha in these lesions showed an inverse relationship. In comparison with 18 HCC arising in noncirrhotic livers, the expression of TGF-alpha is significantly stronger in cirrhotic liver than in noncirrhotic parenchyma and its expression is also stronger in HCC arising in cirrhosis than in HCC arising in noncirrhotic parenchyma. The increased expression of Topo II-alpha and Ki-67 from HGDN to HCC, when compared with cirrhosis, suggests that HGDN is a precursor lesion in hepatocarcinogenesis. The inverse relationship between these proliferative markers and TGF-alpha expression in these lesions and stronger expression of TGF-alpha in HCC arising in cirrhosis suggest that TGF-alpha may play an important role in the early events of liver carcinogenesis.