"IMMUNOCOMPETENT LIVER CELLS IN THE PATHOGENESIS OF FIBROSIS DURING CHEMICAL CASTRATION OF MALE RATS"

Hepatocytes make up only about 2/3 of the total liver cell population. The population of nonparenchymal antigen-presenting cells includes Kupffer cells that are part of the reticuloendothelial system, sinusoidal endothelial cells of the liver and dendritic cells. All three types of antigen-presenting cells are thought to be crucial for maintaining tolerance in non-inflammatory conditions. Macrophages play a key role in creating the body's line of defense. The implementation of this function is carried out due to the direct mechanism of action and also due to indirect - processing and presentation of antigenic determinants to T-lymphocytes. How specific populations of macrophages contribute to the development of diseases and regeneration of the liver is the subject of constant debate. Characterization of human macrophage populations provides a valuable basis for studying their role in liver pathology. Each subtype of tissue macrophage has its own unique gene expression profile, which allows it to function in synergy with the tissue in which it is located. As a result of activation of Kupffer and Ito cells, mainly due to their production of collagen, the process of liver fibrogenesis is initiated. Liver disease models in mice that block androgen receptors have shown that androgen / androgen receptor signaling inhibits the development of steatosis, viral hepatitis, and cirrhosis. Preliminary clinical trials have shown that drugs that inhibit the activity of sex steroids can control the growth and invasiveness of hepatocellular carcinoma in certain patients. Thus, the aim of our further study was to elucidate the qualitative and quantitative changes in immunocompetent liver cells during chemical castration of male rats caused by the introduction of a solution of triptorelin acetate at different time intervals.

GeromiRs Are Downregulated in the Tumor Microenvironment during Colon Cancer Colonization of the Liver in a Murine Metastasis Model

Cancer is a phenomenon broadly related to ageing in various ways such as cell cycle deregulation, metabolic defects or telomerases dysfunction as principal processes. Although the tumor cell is the main actor in cancer progression, it is not the only element of the disease. Cells and the matrix surrounding the tumor, called the tumor microenvironment (TME), play key roles in cancer progression. Phenotypic changes of the TME are indispensable for disease progression and a few of these transformations are produced by epigenetic changes including miRNA dysregulation. In this study, we found that a specific group of miRNAs in the liver TME produced by colon cancer called geromiRs, which are miRNAs related to the ageing process, are significantly downregulated. The three principal cell types involved in the liver TME, namely, liver sinusoidal endothelial cells, hepatic stellate (Ito) cells and Kupffer cells, were isolated from a murine hepatic metastasis model, and the miRNA and gene expression profiles were studied. From the 115 geromiRs and their associated hallmarks of aging, which we compiled from the literature, 75 were represented in the used microarrays, 26 out of them were downregulated in the TME cells during colon cancer colonization of the liver, and none of them were upregulated. The histone modification hallmark of the downregulated geromiRs is significantly enriched with the geromiRs miR-15a, miR-16, miR-26a, miR-29a, miR-29b and miR-29c. We built a network of all of the geromiRs downregulated in the TME cells and their gene targets from the MirTarBase database, and we analyzed the expression of these geromiR gene targets in the TME. We found that Cercam and Spsb4, identified as prognostic markers in a few cancer types, are associated with downregulated geromiRs and are upregulated in the TME cells.

Descriptive Histopathological and Ultrastructural Study of Hepatocellular Alterations Induced by Aflatoxin B1 in Rats

Liver sinusoids are lined by fenestrated endothelial cells surrounded by perisinusoidal cells, Kupffer cells, and pit cells, as well as large granular lymphocytes. The functional ability of the liver cells can be substantially modified by exposure to toxins. In the current work, we assessed the histopathological and ultrastructural effects of a time-course exposure to aflatoxin B1 (AFB1) on the hepatic structures of rats. A total of 30 adult female Wistar rats were randomly divided into three groups: a control group, a group orally administered 250 µg/kg body weight/day of AFB1 for 5 days/week over 4 weeks, and a group that received the same AFB1 treatment but over 8 weeks. Histopathological and ultrastructural examinations of hepatocytes revealed massive vacuolar degeneration and signs of necrosis. Furthermore, the rat liver of the treated group exhibited damage to the sinusoidal endothelium, invasion of the space of Disse with hyperactive Kupffer cells, and some immune cells, as well as Ito cells overloaded with lipids. In addition, damaged telocytes were observed. Taken together, our results indicate that AFB1 induces irreversible adverse effects on the livers of rats.

Ultra structural Studies of Mouse Liver in Castrated Subjects Treated with Grape Juice

The present study was designed to evaluate the alterations in the liver tissues especially ITO and Kupffer cells of both castrated and castrated mice treated with10 µl/g of grape juice. The present study was conducted on forty five healthy males of Swiss albino mice, which were divided into 3 groups (N= 15 mice per each group). The first group was intact (control); the second one was castrated and the third group was castrated treated with 10 µl/g of grape juice. The ultra-structure sections of liver tissue from intact (control) group showed normal structure of both hepatocytes and sinusoids, with smooth external surfaces. Whereas ultra-sections from castrated group resulted in: degeneration of hepatocytes, deterioration of sinusoids; rough external surfaces, with aggregations of lipid droplets and white blood cells as compared with the control group. However treatment of castrated subject's with10µl/g of grape juice resulted in activation the regeneration processes in both hepatocytes and sinusoids, with smooth appearance of the external surfaces as compared with control group. The present study concluded that surgical castration aggravated increased hepatic steatosis and increased inflammatory response by increased activation of Kupffer and Ito cells, these effects could be reserved by aggravated increased grape juice administration.

An Integrative Omics Approach Reveals Involvement of BRCA1 in Hepatic Metastatic Progression of Colorectal Cancer

(1) Background & Aims: The roles of different cells in the tumor microenvironment (TME) are critical to the metastatic process. The phenotypic transformation of the liver cells is one of the most important stages of the hepatic metastasis progression of colorectal cancer (CRC). Our aim was to identify the major molecules (i.e., genes, miRNAs and proteins) involved in this process. (2) Methods: We isolated and performed whole-genome analysis of gene, miRNA, and protein expression in three types of liver cells (Ito cells, Kupffer cells, and liver sinusoidal endothelial cells) from the TME of a murine model of CRC liver metastasis. We selected the statistically significant differentially expressed molecules using the Student’s t-test with Benjamini-Hochberg correction and performed functional statistically-significant enrichment analysis of differentially expressed molecules with hypergeometric distribution using the curated collection of molecular signatures, MSigDB. To build a gene-miRNA-protein network centered in Brca1, we developed a software package (miRDiana) that collects miRNA targets from the union of the TargetScan, MicroCosm, mirTarBase, and miRWalk databases. This was used to search for miRNAs targeting Brca1. We validated the most relevant miRNAs with real-time quantitative PCR. To investigate BRCA1 protein expression, we built tissue microarrays (TMAs) from hepatic metastases of 34 CRC patients. (3) Results: Using integrated omics analyses, we observed that the Brca1 gene is among the twenty transcripts simultaneously up-regulated in all three types of TME liver cells during metastasis. Further analysis revealed that Brca1 is the last BRCA1-associated genome surveillance complex (BASC) gene activated in the TME. We confirmed this finding in human reanalyzing transcriptomics datasets from 184 patients from non-tumor colorectal tissue, primary colorectal tumor and colorectal liver metastasis of the GEO database. We found that the most probable sequence of cell activation during metastasis is Endothelial→Ito→Kupffer. Immunohistochemical analysis of human liver metastases showed the BRCA1 protein was co-localized in Ito, Kupffer, and endothelial cells in 81.8% of early or synchronous metastases. However, in the greater part of the metachronous liver metastases, this protein was not expressed in any of these TME cells. (4) Conclusions: These results suggest a possible role of the co-expression of BRCA1 in Ito, Kupffer, and sinusoidal endothelial cells in the early occurrence of CRC liver metastases, and point to BRCA1 as a potential TME biomarker.

The effect of hyperhomocysteinemia on the patterns of electron microscopic changes in the liver of adult rats

One of the important tasks of modern science is to find biochemical markers that would be able to reflect the risks of development and the nature of the course of various diseases, as well as to predict their possible consequences. In recent years, a significant number of compounds that can affect the biochemical profile of the organism have been identified. Homocysteine – a product of methionine metabolism, belongs to one of these markers, and the effects of its influece on the structure and function of various organs are being actively studied by modern researchers. The aim of the study is to find the patterns of electron microscopic changes in the liver structure of adult rats with hyperhomocysteinemia. The experimental study was performed on 22 white nonlinear mature male rats, which were divided into a control group and an experimental group. A model of persistent hyperhomocysteinemia was created by administering to rats of experimental group thiolactone homocysteine at a dose of 200 mg/kg body weight intragastrically for 60 days. The study of ultrastructural changes in the liver of rats was performed using an electron microscope PEM-125K. In adult rats with experimental hyperhomocysteinemia at the ultrastructural level, dystrophic and destructive changes in hepatocytes, endotheliocytes in the walls of sinusoids and Kupffer cells were found. These changes were more pronounced than in young rats with experimental hyperhomocysteinemia. Revealed structural changes in decompensation (depletion) of mitochondria – fewer number of cristae and enlightened matrix. In contrast to young rats, adult rats with hyperhomocysteinemia in the perisinusoidal spaces showed elongated Ito cells, a significant proportion of the cytoplasm is occupied by the Golgi complex and granular endoplasmic reticulum tanks, indicating protein synthesis for export. In Ito cells, the content of fat droplets, which are located on opposite poles of cells, is reduced. This morphological picture manifests the transformation of Ito cells into fibroblasts.

Біополімери сполучної тканини сироватки крові в коней за отруєння чорнокоренем лікарським (Cynoglоssum officinаle)

<p>The results of a complex study of the effect of Cynoglossum officinale on the organism of horses were presented in the article. The research was conducted in the period from 2014 to 2017 at the Derkulsky stud farm in Lugansk region. It has been established that poisoning by Cynoglossum officinale causes a violation of the hepatotoxic biliary system and the development of cirrhosis in horses. A set of biochemical parameters of blood serum that may be markers of dystrophic processes in liver tissues was determined. The most informative indicators for diagnosis of cirrhosis of the liver in horses are indicators that characterize the state of the connective tissue, namely the content of glycosaminoglycans and their fractions. There was a tendency to increase the number of general GAGs in the horses which died, compared to the control group. In animals that survived, this indicator increased significantly (p≤0.05) compared to the control, indicating the development of fibrous changes in the tissues of parenchymal organs. After analysis of the level of separate GAGs fractions, it was determined that level I of GAGs fraction in all groups was higher than the reference norm, indicating a metabolic abnormality of GAGs of the connective tissue, in particular chondroitin-6-sulfate, especially in animals that survived after poisoning (p≤0.05). Level II of GAGs fraction for most of the horses which died after Cynoglossum officinale poisoning was also higher than the norm: 3.12 ± 0.49 un., and in the horses that survived this figure was 2.67 ± 0,23 un. Consequently, after Cynoglossum officinale poisoning the formation of cholesterol-4 and dermatan sulfates increased that is usually observed in the degenerative processes in the liver and is accompanied with the growth of the connective tissue. Level III of GAGs fraction, the major part of which is heparan and keratan sulfates, increased by 2.6 times (p≤0.05) in case of death of animals after Cynoglossum officinale poisoning and by 2.4 times (p≤0.05) in the horses that survived. It is possible that depolymerization of heparan sulfate occurs in the stromal elements of the liver and of other internal organs which is replaced by chondroitin-4-sulfates as a result of poisoning of the animals by Cynoglossum officinale while Ito cells are transforming into myofibroblasts. These data are confirmed by morphological studies of the liver, which are manifested by dystrophic changes, on the background of cell cytology, hepatodepressive syndrome and an increase in the volume of connective tissue which leads to the death of most of the horses and to the development of chronic pathological process in animals that survive.<strong></strong></p>