Hepatocyte Nuclei Research Articles

Site-specific identification and validation of hepatic histone nitration in vivo: Implications for alcohol-induced liver injury.

Oxidative and nitrative stress have been implicated in the molecular mechanisms underlying a variety of biological processes and disease states including cancer, aging, cardiovascular disease, neurological disorders, diabetes, and alcohol-induced liver injury. One marker of nitrative stress is the formation of 3-nitrotyrosine, or protein tyrosine nitration (PTN), which has been observed during inflammation and tissue injury; however, the role of PTN in the progression or possibly the pathogenesis of disease is still unclear. We show in a model of alcohol-induced liver injury that an increase in PTN occurs in hepatocyte nuclei within the liver of wild-type male C57BL/6J mice following chronic ethanol exposure (28 days). High-resolution mass spectrometric analysis of isolated hepatic nuclei revealed several novel sites of tyrosine nitration on histone proteins. Histone nitration sites were validated by tandem mass spectrometry (MS/MS) analysis of representative synthetic nitropeptides equivalent in sequence to the respective nitrotyrosine sites identified in vivo. We further investigated the potential structural impact of the novel histone H3 Tyr41 (H3Y41) nitration site identified using molecular dynamics (MD) simulations. MD simulations of the nitrated and non-nitrated forms of histone H3Y41 showed significant structural changes at the DNA interface upon H3Y41 nitration. The results from this study suggest that, in addition to other known post-translational modifications that occur on histone proteins (e.g., acetylation and methylation), PTN could induce chromatin structural changes, possibly affecting gene transcription processes associated with the development of alcohol-induced liver injury.

A Quantitative Study on the Protective Effects of Resveratrol against Bisphenol A-induced Hepatotoxicity in Rats: A Stereological Study.

Background: Bisphenol A (BPA) is a widely used chemical with toxic effects on the liver. Resveratrol (RES) is an herbal compound with protective properties. This study aimed to investigate the protective effects of RES on the liver in rats exposed to BPA.Methods:This study was conducted in 2018 in Shiraz, Iran. Thirty Sprague-Dawley male rats were divided into five groups: a control group (distilled water), a sham group (olive oil as a BPA solvent), a BPA group (50 mg/kg), an RES group (100 mg/kg), and a RES+BPA group (50 mg/kg+100 mg/kg). Olive oil, BPA, and RES were administered to the animals via gavage for eight weeks. After eight weeks, the animals’ livers were removed, and stereological measurements were made to obtain the total liver volume, portal triad volumes, hepatocyte nucleus and cytoplasm volumes, hepatocyte numbers, sinusoidal space volumes and lengths, and Kupffer cell (KC) numbers. The data were analyzed using the one-way analysis of variance testResults: The hepatocyte number, the total liver volume, and hepatocyte nucleus and cytoplasm volumes in the BPA group decreased by 41% (P<0.001), 18% (P<0.001), 32% (P=0.030), and 37% (P=0.014), respectively. The number of KCs and the length of sinusoids in the BPA group were increased compared with all the other groups (P<0.001). Our histological study revealed vacuolization, sinusoidal space dilatation, and congestion in the BPA group.Conclusion: In this study, the RES group, compared with the BPA group, exhibited a decrease in the total volume and length of sinusoids and the number of KCs. Additionally, the RES group showed an increase in the total liver volume, hepatocyte nucleus and cytoplasm volumes, portal triad volumes, and hepatocyte numbers after oral administration

The Correlation of Histopathological Findings with Ultrastructural Changes in Hepatocytes after Yangonin “Ya”-Intoxicated Rats Alone and In Combination with EtOH: Sub-Acute & Sub-Chronic Study

Yangonin “Ya” has been used for centuries as a herbal supplement, for its mood-altering properties. It has been used as a recreation agent, for relaxation, as well as for pain relief. However, hepatotoxicity is a widespread problem associated with medicines in general. Most herbal supplements are metabolized by the liver, and thus the liver represents the target organ. At present, Yangonin toxicity appears to be “idiosyncratic”. Therefore, a study was designed in order to investigate the organelle-based changes in hepatocytes, after treatment with Yangonin alone and in combination with EtOH. Thirty rats were divided into five groups comprising of six animals each. The groups comprised of the control groups {(NCx) & (PCx)}, Yangonin (Ya) group, ethanol (EtOH) group, and the combination of (Ya) and ethanol (EtOH+Ya) group. The experiment was conducted over a period of 14 weeks, as a sub-chronic study. At the end of the 14 th week, mitochondria, peroxisome, rough and smooth endoplasmic reticulum, and nuclei of hepatocytes, were evaluated using a scoring system. The results were compared with histopathological findings, as well. Treatment with Ya significantly induced hepatotoxic scores as compared to the control groups. Organelle injury scores increased significantly with Ya treatment, while rats that received “EtOH+Ya” showed the severest lesions of liver scores such as, severe hepatocellular degeneration, necrosis, and hypertrophy. Ultrastructural and histopathological scores in both groups were in very strong correlation (r = 0.928 for EtOH, r = 0.921 for Ya alone and r = 0.903 for Ya plus EtOH group). In conclusion, ethanol enhanced the sedative and hypnotic activity of Ya, and markedly increased toxicity. Findings based on TEM examination of organelles, supported the histological results as well as tissue lesions/injuries in hepatocytes, a result of hepatotoxin-induced hepatopathy.

Hepatotoxic effects of melamine exposure from the weaning period in rats: a flow cytometric, electron microscopic, and histopathologic study.

This study aims to investigate the effects of melamine exposure from the weaning period (21st postnatal days in rats) on liver tissue. Female Wistar albino rats (n=18) were divided into three groups. About 0.1-ml saline was applied to the control group by gavage for 21days from the postnatal 21st day. The second group was taken 50-mg/kg melamine (in 0.1-ml saline) and the third group was taken 75-mg/kg melamine (in 0.1-ml saline) p.o. On the postnatal 45th day, all rats were sacrificed under anesthesia. Then, liver tissues were cut into three parts and two of them placed in neutral formalin for histopathological and flow cytometric analysis, and one of them placed in 2.5% glutaraldehyde. Histopathological analysis was performed with hematoxylin & eosin, Masson trichrome, periodic acid Schiff stained sections, and also with transmission electron microscopy. Apoptosis (Annexin V positivity) was analyzed by flow cytometry. According to histopathological analysis, hepatocyte damage, sinusoidal dilatation, and inflammatory cell infiltration significantly increased in both melamine groups compared with the control group. Apoptosis significantly increased in the 50 and 75-mg melamine groups compared with the control group. In the results of transmission electron microscopy analysis, there was abnormal chromatin distribution in the hepatocyte nuclei, loss in the cristae of the mitochondria, and organelle loss in large areas in the cytoplasm in both melamine exposure groups. As result, melamine exposure from the weaning period causes liver damage with increasing doses.

Preparation of the peroxisome proliferator-activated receptor α polyclonal antibody: Its application in fatty liver hemorrhagic syndrome

Peroxisome proliferator-activated receptor α (PPARα) play a key role in the regulation of metabolic homeostasis, inflammation, cellular growth, and differentiation. To further explore the potential role of PPARα in the energy homeostasis of fatty liver hemorrhagic syndrome (FLHS), we reported the prokaryotic expression and purification of chicken PPARα subunit protein, and successfully prepared a polyclonal antibody against PPARα recombinant protein. The 987 bp PPARα subunit genes were cloned into the pEASY-T3 clone vector. Then the plasmid PCR products encoding 329 amino acids were ligated to pEASY-Blunt E2 vector and transformed into BL21 to induce expression. The recombinant PPARα subunit protein, containing His-tag, was purified by affinity column chromatography using Ni-NTA affinity column. Rabbit antiserum was generated by using the concentration of recombinant PPARα subunit protein as the antigen. The results of western blotting showed that the antiserum can specifically recognize chicken endogenous PPARα protein. Immunohistochemistry and immunofluorescence showed that the PPARα mainly existed in the nucleus of hepatocytes, renal epithelial cells and hypothalamic endocrine nerve cells. More importantly, western blotting and real-time quantitative PCR indicated that FLHS significantly decreased the expression of PPARα.

Spillover events of rabbit haemorrhagic disease virus 2 (recombinant GI.4P-GI.2) from Lagomorpha to Eurasian badger.

Rabbit haemorrhagic disease (RHD) is a major threat to domestic and wild European rabbits. Presently, in Europe, the disease is caused mainly by Rabbit haemorrhagic disease virus 2 (RHDV2/b or Lagovirus europaeus GI.2), the origin of which is still unclear, as no RHDV2 reservoir hosts were identified. After the RHDV2 emergence in 2010, viral RNA was detected in a few rodent species. Furthermore, RHDV2 was found to cause disease in some hare species resembling the disease in rabbits, evidencing the ability of the virus to cross the species barrier. In this study, through molecular, histopathologic, antigenic and morphological evidences, we demonstrate the presence and replication of RHDV2 in Eurasian badgers (Meles meles) found dead in the district of Santarém, Portugal, between March 2017 and January 2020. In these animals, we further classify the RHDV2 as a Lagovirus europaeus recombinant GI.4P-GI.2. Our results indicate that Meles meles is susceptible to RHDV2, developing systemic infection, and excreting the virus in the faeces. Given the high viral loads seen in several organs and matrices, we believe that transmission to the wild rabbit is likely. Furthermore, transmission electron microscopy data show the presence of calicivirus compatible virions in the nucleus of hepatocytes, which constitutes a paradigm shift for caliciviruses' replication cycle.

SYSTEMIC AMYLOIDOSIS IN YOUNG MICE INDUCED BY HUMAN SALIVA ADMINISTRATION

The urgency of the study lies in the fact that for the first time it was proved in the experiment that intraperitoneal administration of human saliva to young mice causes the development of systemic amyloidosis, comparable to hereditary systemic amyloidosis in humans, induced by mutagenic changes in saliva lysozyme. The aim of the research: to test human saliva as an amyloidogen in a model experiment on young mice in comparison with the albumin model of amyloidosis that we developed earlier. White male mice weighing 20.0–25.0 g were divided into six groups: Intact mice (5); 30 days 1 time every other day were intraperitoneally administered to groups: 1 (5) soy cream substitute TU 9199-004-58706213-10 15 10 g/100 ml water 0.1 ml/10 g; 2 (3) saliva of a healthy person (SHP) 0.5 ml; 3 (3) SHP and Ciprofloxacin (C) 0.05 mg/10 g of weight; 4 (3) saliva of a person with chronic tonsillitis (remission, SCT); 5 (3) SCT+C. Kidney weight changed from 176.0±21 mg in intact mice (IM) to 197±43,0, 195,0±18,0, 195,0±18,0, 183,0±44,0, 153,0±25,0 mg, respectively. The number of cells per visual field of the tubular epithelium decreased by 1.3, 1.2, 1.6, 1.4, 1.4 times from the number of cells per visual field in IM 380.0±84.0 (p = 0.00), glomerular cells – by 1.4, 1.1, 1.3, 1.2, 1.2 times from the number of glomerular cells in IM 34.0±11.0 (p = 0.02), in groups 1-5, respectively. The glomerular area decreased by 2.4, 2.7, 2.3, 2.4, 3.0 times from the average glomerular area in IM (3163.7±832.7 mm2, p = 0.0000). The relative area of amyloid lesion when stained with Congo red: 18.4±8.2% (group 1), 26,7±10,6, 35,0±11,9, 45,7±13,2, 63,6±14,0% (groups 1-5). The spleen mass and length increased from 133.0±16.0 mg (IM) by 1.7, 1.7, 1.8, 2.1, 1.7 times and from 17.0±2.0 mm (IM) by 1.2, 1.2, 1.3, 1.4, 1.2 times, the number of cells per visual field decreased from 1318±205 (IM) by 1.7, 2.0, 3.3, 2.1, 2.0 times, groups 1-5, respectively (p &lt; 0.01). The relative area of amyloid lesion in Congo red staining: 11,4±9,4%, 28,2±16,0, 27,9±20,8, 20,9±12,2, 16,5±8,3% (groups 1-5). The liver mass changed from 1.4±0.15 g (IM) to 1,57±0,26, 1,45±0,18, 1,53±0,1, 1,71±0,3, 1,36±0,4 g, the number of cells per visual field decreased from 67.0±15.0 (IM) by 1.9, 1.4, 1.8, 2.5, 1.9 times, the area of hepatocyte nuclei – from 54.0±12.3 µm (IM) by 3.1, 3.6, 4.2, 3.1, 3.3 times (groups 1-5, respectively, p &lt; 0.01). The relative area of amyloid lesion in Congo red staining: 6,8±4,6%, 15,3±11,0, 24,5±12,8, 9,8±8,5, 12,6±2,3% (groups 1-5). Conclusions: 1) human saliva when administered intraperitoneally causes severe systemic amyloidosis in young mice with damage to the liver, kidneys and the spleen, which manifests more by cytotoxic effect than the volume of amyloid deposition; 2) human saliva contains a more active amyloidogen than albumin in combination with fillers of the soy cream substitute formulation; 2) human saliva of a person with chronic tonsillitis in remission is more amyloidogenic than the saliva of a healthy person; 3) Ciprofloxacin, administered in a therapeutic dose during the amyloid model formation, moderately increases the severity of amyloid organ damage; 4) human saliva can be used to simulate amyloidosis in an experiment on young mice; 5) the liver may contain enzymatic systems that perform the function of amyloidoclasia.

Nuclear-nucleolar relationships and nucleolar stress in hepatocytes in hyperhomocysteinemia

Hyperhomocysteinemia causes stress of the endoplasmic reticulum, which suggests the formation of nucleolar stress. The purpose of this work is to clarify the relationship between structural changes in the nucleus and the region of the nucleolar organizer in hyperhomocysteinemia to prove nucleolar stress in hyperhomo-cysteinemia, which can serve as an additional diagnostic marker of the disease. The object of the study was white mongrel rats with methionine-induced hyperhomocysteinemia. Histologic sections of the liver were stained with hematoxylin and eosin (to assess the histological structure of the organ, hepatocyte nuclei), ammonia silver (to analyze the areas of the nucleolar organizer - AgNORs). Morphometry has allowed to establish that hyperhomocysteinemia decreases the number of nuclei (1,86 times, p

Alterations of Gut Microbiota by Overnutrition Impact Gluconeogenic Gene Expression and Insulin Signaling.

A high-fat, Western-style diet is an important predisposing factor for the onset of type 2 diabetes and obesity. It causes changes in gut microbial profile, reduction of microbial diversity, and the impairment of the intestinal barrier, leading to increased serum lipopolysaccharide (endotoxin) levels. Elevated lipopolysaccharide (LPS) induces acetyltransferase P300 both in the nucleus and cytoplasm of liver hepatocytes through the activation of the IRE1-XBP1 pathway in the endoplasmic reticulum stress. In the nucleus, induced P300 acetylates CRTC2 to increase CRTC2 abundance and drives Foxo1 gene expression, resulting in increased expression of the rate-limiting gluconeogenic gene G6pc and Pck1 and abnormal liver glucose production. Furthermore, abnormal cytoplasm-appearing P300 acetylates IRS1 and IRS2 to disrupt insulin signaling, leading to the prevention of nuclear exclusion and degradation of FOXO1 proteins to further exacerbate the expression of G6pc and Pck1 genes and liver glucose production. Inhibition of P300 acetyltransferase activity by chemical inhibitors improved insulin signaling and alleviated hyperglycemia in obese mice. Thus, P300 acetyltransferase activity appears to be a therapeutic target for the treatment of type 2 diabetes and obesity.

Effects of Circular RNA of Chicken Growth Hormone Receptor Gene on Cell Proliferation.

Animal growth and development are regulated by neural and endocrine growth axes, in which cell proliferation plays key roles. Recently, many research showed that circular RNAs were involved in hepatocyte and myoblast proliferation. Previously, we identified a circular RNA derived from the chicken GHR gene, named circGHR. However, the function of circGHR is unclear. The objective of this study was to investigate circGHR expression pattern and its roles in cell proliferation. Results indicated that circGHR was a closed-loop structure molecule, and it was richer in the nucleus of hepatocytes and myoblast. Real-time PCR showed that circGHR was increased from E13 to the 7th week in the liver but decreased in the thigh and breast muscle. The CCK-8 assay displayed that circGHR promoted cell proliferation. Simultaneously, the biomarker genes PCNA, CCND1, and CDK2 and the linear transcripts GHR and GHBP were upregulated when circGHR was overexpressed. Altogether, these data exhibited that circGHR could promote cell proliferation possibly by regulating GHR mRNA and GHBP expression.

Exogenous activation of toll-like receptor 5 signaling mitigates acetaminophen-induced hepatotoxicity in mice

Acetaminophen (APAP) poisoning is the most common cause of drug-induced acute liver injury (ALI). Our results showed that toll-like receptor 5 (TLR5) was abundantly expressed in hepatocytes and dramatically downregulated in the toxic mouse livers. Hence, we herein investigated the role of TLR5 signaling after APAP overdose. Mice were intraperitoneally (i.p.) injected with APAP to induce ALI, and then injected with flagellin at one hour after APAP administration. Flagellin attenuated APAP-induced ALI based on decreased histopathologic lesions, serum biochemical, oxidative stress, and inflammation. Furthermore, the protective effects of flagellin were abolished by TH1020 (a TLR5 antagonist) treatment. These results suggest that flagellin exerted protective effects on ALI via TLR5 activation. Mechanistically, flagellin injection promoted the translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) to the nucleus in hepatocytes. Consistent with the in vivo results, flagellin increased the activation of Nrf2 in hepatocytes, resulting in decreased APAP toxicity. ML385, a selective inhibitor of Nrf2, abolished the flagellin-mediated hepatoprotective effects in damaged livers and hepatocytes. Additionally, the flagellin-induced Nrf2 translocation was dependent upon the activation of TLR5-JNK/p38 pathways. These findings suggest that TLR5 signaling-induced Nrf2 activation, at least partially, contributed to the protection against APAP-induced ALI by flagellin treatment.

HBV Core Protein Is in Flux between Cytoplasmic, Nuclear, and Nucleolar Compartments.

ABSTRACTHepatitis B virus (HBV) core protein (Cp) can be found in the nucleus and cytoplasm of infected hepatocytes; however, it preferentially segregates to a specific compartment correlating with disease status. Regulation of this intracellular partitioning of Cp remains obscure. In this paper, we report that cellular compartments are filled and vacated by Cp in a time- and concentration-dependent manner in both transfections and infections. At early times after transfection, Cp, in a dimeric state, preferentially localizes to the nucleolus. Later, the nucleolar compartment is emptied and Cp progresses to being predominantly nuclear, with a large fraction of the protein in an assembled state. Nuclear localization is followed by cell-wide distribution, and then Cp becomes exclusively cytoplasmic. The same trend in Cp movement is seen during an infection. Putative nucleolar retention signals have been identified and appear to be structure dependent. Export of Cp from the nucleus involves the CRM1 exportin. Time-dependent flux can be recapitulated by modifying Cp concentration, suggesting transitions are regulated by reaching a threshold concentration.

Characterization of Hepatitis B Precore/Core-Related Antigens.

Current therapies rarely cure chronic hepatitis B virus (HBV) infection due to the persistence of the viral episome, the covalently closed circular DNA (cccDNA), in hepatocytes. The hepatitis B virus core-related antigen (HBcrAg), a mixture of the viral precore/core gene products, has emerged as one potential marker to monitor the levels and activities of intrahepatic cccDNA. In this study, a comprehensive characterization of precore/core gene products revealed that HBcrAg components included the classical hepatitis B virus core antigen (HBc) and e antigen (HBeAg) and, additionally, the precore-related antigen, PreC, retaining the N-terminal signal peptide. Both HBeAg and PreC antigens displayed heterogeneous proteolytic processing at their C termini resulting in multiple species, which varied with viral genotypes. HBeAg was the predominant form of HBcrAg in HBeAg-positive patients. Positive correlations were found between HBcrAg and PreC, between HBcrAg and HBeAg, and between PreC and HBeAg but not between HBcrAg and HBc. Serum HBeAg and PreC shared similar buoyant density and size distributions, and both displayed density and size heterogeneity. HBc, but not HBeAg or PreC antigen, was found as the main component of capsids in DNA-containing or empty virions. Neither HBeAg nor PreC protein was able to form capsids in cells or in vitro under physiological conditions. In conclusion, our study provides important new quantitative information on levels of each component of precore/core gene products as well as their biochemical and biophysical characteristics, implying that each component may have distinct functions and applications in reflecting intrahepatic viral activities.IMPORTANCE Chronic hepatitis B virus (HBV) infection afflicts approximately 257 million people, who are at high risk of progressing to chronic liver diseases, including fibrosis, cirrhosis, and hepatocellular carcinoma. Current therapies rarely achieve cure of HBV infection due to the persistence of the HBV episome, the covalently closed circular DNA (cccDNA), in the nuclei of infected hepatocytes. Peripheral markers of cccDNA levels and transcriptional activities are urgently required to guide antiviral therapy and drug development. Serum hepatitis B core-related antigen (HBcrAg) is one such emerging peripheral marker. We have characterized the components of HBcrAg in HBV-infected patients as well as in cell cultures. Our results provide important new quantitative information on levels of each HBcrAg component, as well as their biochemical and biophysical characteristics. Our findings suggest that each HBcrAg component may have distinct functions and applications in reflecting intrahepatic viral activities.

Histological Effect of Androgenic Anabolic Steroids on Liver

Abstract: Anabolic androgenic steroids (AAS) they are the synthetic type of the natural male sex hormone(testosterone), they are widespread used amongst athletes to enhance performance. Abuse of AAS is commonamongst players and it is usually accompanied by a many medically based complications. It was reportedthat hepatic problems include cholestasis, elevation of liver enzymes e.g. aminotransferases, as well as,benign hepatic adenomas, jaundice and to less extent of hepatocellular carcinoma was associated with theiruse.A total of (12) adult New Zealand rabbits (Oryctolagus cuniculus) male, aged one year was selected. 2control animals and 10 were treated with injections intramuscularly of the AAS, nandrolone decanoate(15 mg/kg) three times a week for 12 weeks. At the end of experiment the animals were sacrificed and theliver was dissected out and fixed using 10% buffered formalin-saline to prepare blocks for staining withhaematoxylin and eosin for histological examination using the light microscope.The liver of treated animals reveals that there are a mild to severe vascular congestion. There is swelling ofhepatocytes, and inflammatory cell infiltration. Perivascular fibrosis, cellular necrosis was observed in otherslides with sinusoidal congestions and extrabiliary bile pigments deposits.The benefit of AAS comes with unwanted side effects. The total volume of the hepatocytes and sinusoidswere increased in the studied animals. The total number of hepatocytes nuclei in experimental group alsoincreased. The damage of the liver cells or at least increased permeability of the hepatocellular membranewhich is noticed in the present work could explain the increment of plasma levels of liver enzymeswhich was studied by other researchers, as they notice an elevation liver enzymes activity such as alanineaminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (AP), gamma glutamyltranspeptidase (GGT), and lactate dehydrogenase(LDH)..Patients and physicians must kept in mind that the sequelae of AAS abuse are life threatening. So peopleshould be aware about the complications of AAS use and a periodic examination of liver function and checkout should be done to those treated groups.

Nuclear VEGFR-2 Expression of Hepatocytes Is Involved in Hepatocyte Proliferation and Liver Regeneration During Chronic Liver Injury.

The pathological role of vascular endothelial growth factor receptor 2 (VEGFR-2) in chronic liver injury and liver regeneration is not fully understood. This study analysed the role of VEGFR-2 in liver fibrosis and its regeneration process. We administered intraperitoneally 50 mg/kg to 300 mg/kg thioacetamide (TAA) to 9-week-old male mice for 17 weeks. We measured levels of VEGFR-2 protein and identified the location of cells that specifically express VEGFR-2. VEGFR-2 is rarely expressed in normal hepatocytes. However, high VEGFR-2 expression in liver sinusoidal endothelial cells was noted in the TAA group. Conversely, the group that experienced regeneration from liver fibrosis showed significantly higher VEGFR-2 expression in the nucleus of hepatocytes compared to the other groups. VEGFR-2 plays a pivotal role in the nucleus of hepatocytes during liver regeneration and VEGFR-2 may be closely related to cell division. Therefore, VEGFR-2 may be a new therapeutic target for liver regeneration.

Spontaneous poisoning by Cestrum intermedium in dairy cattle

ABSTRACT: Acute hepatotoxicity caused by plants poisoning is responsible for economic losses in farm animals in Brazil. Reports of Cestrum intermedium natural poisoning in cattle are not commonly described in Rio Grande do Sul (RS). This study aimed to document an outbreak of spontaneous C. intermedium poisoning in dairy cattle in the Central-Eastern Mesoregion of RS. Three nine-month-old Holstein and Jersey heifers were affected after they were placed in a small paddock with shortage forage. In this area, specimens of C. intermedium Sendtn with signs of consumption were observed. Morbidity and lethality rates were 100% and clinical courses ranged from 9 to 12 hours. At post mortem examination of the three heifers, there was predominance of acute liver lesions. The liver was moderately enlarged and on the cut surface there was a marked accentuation of the lobular pattern and hemorrhage. Inside the rumen, partially digested C. intermedium Sendtn leaves were observed. The histological aspects of the liver were mostly centrilobular coagulative necrosis and hemorrhage, frequently extended to the midzonal region. The immunohistochemistry technique was performed, in which the polyclonal antibody caspase 3 was used in liver fragments. Moderate to marked immunolabeling was observed in the cytoplasm and nucleus of hepatocytes, predominantly on the periphery of areas of hepatic necrosis indicating cell apoptosis. The diagnosis of C. intermedium Sendtn poisoning in dairy cattle in this study was based on epidemiological, clinical and anatomopathological findings. Since the C. intermedium poisoning is uncommon in dairy cattle, we are describing it for the first time in the Central-Eastern Mesoregion of RS, and represents a differential diagnosis of other acute toxic liver diseases in cattle.

Effects of Carvedilol on liver ischemia-reperfusion injury in rats.

The aim of this study was to analyze the potential protective effect of Carvedilol against liver ischemia-reperfusion (I/R) injury in rats. A total of 40 Wistar albino rats were randomly divided into four groups (n=10 each). Group I (Sham/Control group) underwent only laparotomy, Group II (Carvedilol group) was administered carvedilol and then underwent laparotomy, Group III (I/R group) underwent laparotomy and hepatic ischemia/reperfusion, and Group IV (I/R + Carvedilol group) was administered carvedilol and then underwent laparotomy and hepatic ischemia/reperfusion. Blood samples were collected for malondialdehyde, glutathione (GSH), and myeloperoxidase (MPO) analysis. Liver sections were obtained for histopathological analysis and stained with hematoxy-lin-eosin. Tumor necrosis factor-α (TNF-α) and Caspase-3 primary antibodies were used for the immunohistochemical analysis. Serum GSH levels increased in the I/R + Carvedilol group. MPO activity was increased significantly in the IR group. In I/R + Carvedilol group, serum MPO levels were similar to the control group. Histopathological findings showed reduced dilatation and congestion in vena centralis, regenerative changes in hepatocyte cells with the protected nucleus structure in the I/R + Carvedilol group. Hepatocyte nuclei with increased pycnosis and apoptosis and the dilated vena centralis were observed in I/R group. In the control group, TNF-α showed a positive reaction in macrophage cells around vena centralis. An increase in TNF-α expression was observed in hepatocyte cells of I/R group. Positive expression of caspase-3 in hepatocyte cells and a small number of endothelial and Kupffer cells were seen in I/R group. However, negative caspase-3 expression was seen in hepatocyte, endothelial, and Kupffer cells in I/R + Carvedilol group. Carvedilol may prevent initiation of oxidative stress process, inflammation induction and apoptotic progression.

ПРЕНАТАЛЬНОЕ ВОЗДЕЙСТВИЕ СВИНЦА НА СТРУКТУРУ ПЕЧЕНИ НОВОРОЖДЕННЫХ КРЫС

The liver structure of the offspring of white rats was studied under conditions of the action of a low dose lead acetate (1 mg/kg of body weight) female during pregnancy. Histological, morphometric and informational analysis of the liver structures in the control and experiment in newborn rat was carried out. It has been shown that prenatal exposure to low doses of lead acetate does not cause significant damage to the liver structure of newborns. Lymphocytic infiltration in the portal area plethora of central vein, expansion of hemocapillaries were found. A statistically significant increase in the size of the nucleus of the hepatocytes, the number of foci of hematopoiesis in the parenchyma of liver, the expansion of hemocapillaries in the experiment compared with the control was established. The observed changes can be considered as a magnification of an adaptive response to the action of anthropogenic factors in the relationship between the fetus and the maternal organism.

Mapping cccDNA-Host Interactome Identifies Cohesin Complex as a Novel HBV Restriction Factor

Covalently closed circular DNA (cccDNA) of HBV, existing as a stable minichromosome in hepatocyte nucleus, is responsible for persistent HBV infection. Maintainance and sustained replication of cccDNA require its interaction with both viral and proteins. However, cccDNA-interacting host factors limiting its replication remain elusive. Here, by mass-spectrometry based on pull-down with biotinalytaed recombinant cccDNA, called minicircle HBV (MC-HBV), that supports persistent HBV replication and mimics cccDNA minichromosome, we mapped cccDNA-hepatocyte interaction profile, and identified cohesin complex as a cccDNA binding host factor leading to reduced HBV replication. Mechanically, with the help of MAU2-NIPBL complex and CTCF, cohesin loaded on cccDNA and compacted cccDNA to prevent RNAPII enrichment. Interestingly, HBx transcriptionally reduced SMC3 expression to partially relieve the inhibitory role of cohesin complex on HBV replication. In conclusion, our study provides a feasible approach to explore cccDNA-hepatocytes interactome and identifies cohesin complex as a novel HBV restriction factor.

TOXIC EFFECTS OF ULTRA-DISPERSED FORMS OF METALS (Mo AND MoO3) IN THE EXPERIMENT in vivo

TOXIC EFFECTS OF ULTRA-DISPERSED FORMS OF METALS (Mo AND MoO3) IN THE EXPERIMENT in vivo