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Scientific Reports Nov 2020Tilapia lake virus (TiLV) causes high mortality and high economic losses in tilapines. We describe an experimental challenge study focusing on early post challenge...
Tilapia lake virus (TiLV) causes high mortality and high economic losses in tilapines. We describe an experimental challenge study focusing on early post challenge innate immune responses. Nile tilapia (Oreochromis niloticus) were infected with 10 TCID/mL TiLV intraperitoneally, followed by virus quantification, histopathology and gene expression analysis in target (brain/liver) and lymphoid (spleen/headkidney) organs at 3, 7, 12, 17, and 34 days post challenge (dpc). Onset of mortality was from 21 dpc, and cumulative mortality was 38.5% by 34 dpc. Liver and kidney histopathology developed over the period 3-17 dpc, characterized by anisocytosis, anisokaryocytosis, and formation of multinucleated hepatocytes. Viral loads were highest at early time (3 dpc) in liver, spleen and kidney, declining towards 34 dpc. In brain, viral titer peaked 17 dpc. Innate sensors, TLRs 3/7 were inversely correlated with virus titer in brain and headkidney, and IFN-ß and Mx showed a similar pattern. All organs showed increased mRNA IgM expression over the course of infection. Overall, high virus titers downplay innate responses, and an increase is seen when viral titers decline. In silico modeling found that TiLV segments 4, 5 and 10 carry nucleolar localization signals. Anti-viral effects of TiLV facilitate production of virus at early stage of infection.
Topics: Animals; Antibodies, Viral; Brain; Cichlids; Fish Diseases; Gene Expression Regulation; Hepatocytes; Host-Pathogen Interactions; Immunity, Innate; Immunoglobulin M; Interferon-beta; Kidney; Liver; Negative-Sense RNA Viruses; Spleen; Survival Analysis; Time Factors; Toll-Like Receptor 3; Toll-Like Receptor 7
PubMed: 33230226
DOI: 10.1038/s41598-020-73781-y -
BMB Reports Jul 2017We previously reported that p53 plays a role as a key regulator in the tetraploid G1 checkpoint, which is activated by actin damage-induced cytokinesis blockade and then...
We previously reported that p53 plays a role as a key regulator in the tetraploid G1 checkpoint, which is activated by actin damage-induced cytokinesis blockade and then prevents uncoupled DNA replication and nuclear division without cytokinesis. In this study, we investigated a role of Skp2, which targets CDK2 inhibitor p27/Kip1, in actin damage-induced tetraploid G1 arrest. Expression of Skp2 was reduced, but p27/Kip1 was increased, after actin damage-induced cytokinesis blockade. The role of Skp2 repression in tetraploid G1 arrest was investigated by analyzing the effects of ectopic expression of Skp2. After actin damage, ectopic expression of Skp2 resulted in DNA synthesis and accumulation of multinucleated cells, and ultimately, induction of apoptosis. These results suggest that Skp2 repression is important for sustaining tetraploid G1 arrest after cytokinesis blockade and is required to prevent uncoupled DNA replication and nuclear division without cytokinesis. [BMB Reports 2017; 50(7): 379-383].
Topics: Actins; Cyclin-Dependent Kinase Inhibitor p27; Cytokinesis; G1 Phase Cell Cycle Checkpoints; HCT116 Cells; Hep G2 Cells; Humans; S-Phase Kinase-Associated Proteins; Tetraploidy; Tumor Cells, Cultured
PubMed: 28648144
DOI: 10.5483/bmbrep.2017.50.7.063 -
Food Science and Biotechnology Jun 2022Sub-chronic toxicity studies using rats have been conducted for (Maxim.) Hemsley (CW) and Royle ex Wight (CA). CW water extract didn't show any adverse effects whereas...
Sub-chronic toxicity studies using rats have been conducted for (Maxim.) Hemsley (CW) and Royle ex Wight (CA). CW water extract didn't show any adverse effects whereas administering CW powder decreased body weights in complication with decreased food consumptions. In the case of CA water extract, triglyceride and absolute/relative liver weights were elevated and vacuolation was observed in liver. Treated CA powder in male rats increased alanine aminotransferase and aspartate aminotransferase and induced single cell necrosis and multinucleated hepatocyte in liver. As for female rats, increased absolute/relative weights and hypertrophy/vacuolation in adrenal glands and vacuolation in ovaries were observed when administered CA powder. In conclusion, no observed adverse effect level (NOAEL) of CW water extract was over 5000 mg/kg/day, while NOAEL of CW powder was 700 mg/kg/day for female and 150 mg/kg/day for male. In case of CA, NOAEL of water extract was 1500 mg/kg/day for male and 2000 mg/kg/day for female, while NOAEL of powder was 150 mg/kg/day for both gender. To the best of our knowledge, this is the first sub-chronic toxicity study on the adverse effects, target organs and its dose levels of (Maxim.) Hemsley and Royle ex Wight following GLP protocols.
PubMed: 35646417
DOI: 10.1007/s10068-022-01072-5 -
Stem Cell Research & Therapy Dec 2018Adipose tissue is an excellent source for isolation of stem cells for treating various clinical conditions including injuries to the neuromuscular system. Many previous...
BACKGROUND
Adipose tissue is an excellent source for isolation of stem cells for treating various clinical conditions including injuries to the neuromuscular system. Many previous studies have focused on differentiating these adipose stem cells (ASCs) towards a Schwann cell-like phenotype (dASCs), which can enhance axon regeneration and reduce muscle atrophy. However, the stromal vascular fraction (SVF), from which the ASCs are derived, also exerts broad regenerative potential and might provide a faster route to clinical translation of the cell therapies for treatment of neuromuscular disorders.
METHODS
The aim of this study was to establish the effects of SVF cells on the proliferation and differentiation of myoblasts using indirect co-culture experiments. A Growth Factor PCR Array was used to compare the secretomes of SVF and dASCs, and the downstream signaling pathways were investigated.
RESULTS
SVF cells, unlike culture-expanded dASCs, expressed and secreted hepatocyte growth factor (HGF) at concentrations sufficient to enhance the proliferation of myoblasts. Pharmacological inhibitor studies revealed that the signal is mediated via ERK1/2 phosphorylation and that the effect is significantly reduced by the addition of 100 pM Norleual, a specific HGF inhibitor. When myoblasts were differentiated into multinucleated myotubes, the SVF cells reduced the expression levels of fast-type myosin heavy chain (MyHC2) suggesting an inhibition of the differentiation process.
CONCLUSIONS
In summary, this study shows the importance of HGF as a mediator of the SVF effects on myoblasts and provides further evidence for the importance of the secretome in cell therapy and regenerative medicine applications.
Topics: Adipose Tissue; Animals; Cell Differentiation; Cell Proliferation; Female; Humans; Mice; Myoblasts; Rats; Rats, Sprague-Dawley; Stromal Cells
PubMed: 30572954
DOI: 10.1186/s13287-018-1096-6 -
Aging Aug 2018Anillin (ANLN) is an actin-binding protein essential for assembly of cleavage furrow during cytokinesis. Although reportedly overexpressed in various human cancers, its...
Anillin (ANLN) is an actin-binding protein essential for assembly of cleavage furrow during cytokinesis. Although reportedly overexpressed in various human cancers, its role in hepatocellular carcinoma (HCC) is unclear. To address this issue, we confirmed that in 436 liver samples obtained from surgically removed HCC tissues, higher ANLN expression was detected in tumor tissues than in adjacent non-tumor tissues of HCC as measured by immunohistochemistry, quantitative real-time PCR and western blotting. Correlation and Kaplan-Meier analysis revealed that patients with higher ANLN expression were associated with worse clinical outcomes and a shorter survival time, respectively. Moreover, ANLN inhibition resulted in growth restraint, reduced colony formation, and a lower sphere number in suspension culture. Mechanistically, ANLN deficiency induced an increasing number of multinucleated cells along with the activation of apoptosis signaling and DNA damage checkpoints. Furthermore, HBV infection increased ANLN expression by inhibiting the expression of microRNA (miR)-15a and miR-16-1, both of which were identified as ANLN upstream repressors by targeting its 3' untranslated region. Thus, we conclude that ANLN promotes tumor growth by ways of decreased apoptosis and DNA damage. Expression level of ANLN significantly influences the survival probability of HCC patients and may represent a promising prognostic biomarker.
Topics: Adult; Animals; Apoptosis; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Proliferation; Cloning, Molecular; Contractile Proteins; DNA Damage; Female; Gene Expression Regulation, Neoplastic; Gene Knockdown Techniques; Hepatitis B; Hepatitis B virus; Hepatocytes; Humans; Liver Neoplasms; Male; Mice; MicroRNAs; Middle Aged; Neoplasms, Experimental; RNA, Messenger; Random Allocation; Up-Regulation
PubMed: 30103211
DOI: 10.18632/aging.101510 -
Hepatology (Baltimore, Md.) May 2018Recent publications show that classic hepatoblastoma (HBL) is the result of failure of hepatic stem cells to differentiate into hepatocytes, while hepatocellular...
UNLABELLED
Recent publications show that classic hepatoblastoma (HBL) is the result of failure of hepatic stem cells to differentiate into hepatocytes, while hepatocellular carcinoma (HCC) is caused by the dedifferentiation of hepatocytes into cancer stem cells. However, the mechanisms of aggressive HBL and the mechanisms that cause dedifferentiation of hepatocytes into cancer stem cells are unknown. We found that, similar to HCC but opposite to classic HBL, aggressive HBL is the result of dedifferentiation of hepatocytes into cancer stem cells. In both cases of liver cancer, the dephosphorylation of tumor suppressor protein CCAAT/enhancer binding protein α (C/EBPα) at Ser193 (Ser190 in human protein) or mutation of Ser193 to Ala results in a modified protein with oncogenic activities. We have investigated liver cancer in a mouse model C/EBPα-S193A, in a large cohort of human HBL samples, and in Pten/p53 double knockout mice and found that these cancers are characterized by elevation of C/EBPα that is dephosphorylated at Ser190/193. We found that dephosphorylated C/EBPα creates preneoplastic foci with cancer stem cells that give rise to HCC and aggressive HBL. C/EBPα-dependent dedifferentiation of hepatocytes into cancer stem cells includes increased proliferation of hepatocytes, followed by generation of multinucleated hepatocytes and subsequent appearance of hepatocytes with delta-like 1 homolog-positive intranuclear inclusions. We further isolated C/EBPα-dependent multinucleated hepatocytes and found that they possess characteristics of tumor-initiating cells, including elevation of stem cell markers. C/EBPα-dependent cancer stem cells are observed in patients with aggressive HBL and in patients with a predisposition for liver cancer.
CONCLUSION
The earliest steps of adult HCC and aggressive pediatric liver cancer have identical features that include conversion of the tumor suppressor C/EBPα into an oncogenic isoform, which further creates preneoplastic foci where hepatocytes dedifferentiate into cancer cells, giving rise to liver cancer. (Hepatology 2018;67:1857-1871).
Topics: Animals; Blotting, Western; CCAAT-Enhancer-Binding Protein-alpha; Carcinogenesis; Carcinoma, Hepatocellular; Child; Chromatography, High Pressure Liquid; Flow Cytometry; Hepatoblastoma; Hepatocytes; Humans; Liver; Liver Neoplasms; Mice; Mice, Knockout; Neoplastic Stem Cells; Real-Time Polymerase Chain Reaction
PubMed: 29159818
DOI: 10.1002/hep.29677 -
The Korean Journal of Parasitology Oct 2014This study reports the first case of Capillaria hepatica infection in a nutria in Korea. Ten nutrias, captured near the Nakdong River, were submitted to our laboratory...
This study reports the first case of Capillaria hepatica infection in a nutria in Korea. Ten nutrias, captured near the Nakdong River, were submitted to our laboratory for necropsy. White-yellowish nodules were found in the liver of 1 of the nutrias at necropsy. Histologically, the lesions were granulomatous, and infiltrations of lipid-laden macrophages, eosinophils, and several multinucleated giant cells were observed. The lesions consisted of numerous eggs and necrotic hepatocytes. The eggs were lemon-shaped and had polar plugs at the ends of both long sides. The eggs were morphologically identified as those of C. hepatica. Worldwide, C. hepatica infection in nutrias is very rare. Nutrias are a kind of livestock, as well as wildlife; therefore, an epidemiological study for parasitic infections needs to be conducted.
Topics: Animals; Capillaria; Enoplida Infections; Female; Male; Republic of Korea; Rodent Diseases; Rodentia
PubMed: 25352702
DOI: 10.3347/kjp.2014.52.5.527 -
EFSA Journal. European Food Safety... Dec 2019Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific...
Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of astaxanthin-dimethyldisuccinate (ATX-DMDS) for salmonids, crustaceans and other fish. The applicant has provided evidence that ATX-DMDS currently on the market complies with the conditions of authorisation for salmon and trout. ATX and ATX-DMDS are safe for salmonids, crustaceans and fish up to 100 mg ATX/kg complete diet, corresponding to 138 mg ATX-DMDS/kg. The FEEDAP Panel re-assessed the toxicological profile of ATX based on data already considered in 2014, the literature review performed by the applicant and the data available in the context of an EFSA public call for data on ATX. The acceptable daily intake (ADI) of 0.2 mg astaxanthin/kg body weight (bw) per day obtained by applying an uncertainty factor of 200 to a lowest observed adverse effect level (LOAEL) of 40 mg/kg bw per day for the increased incidence of multinucleated hepatocytes observed in a 2-year carcinogenicity study replaces the one of 0.034 mg/kg bw established by the FEEDAP Panel in 2014. The use of ATX-DMDS in the nutrition of salmonids, other fish and crustaceans up to the maximum permitted dietary level is of no concern for the safety of the consumer. No dermal or ocular risk for the users is likely to occur under practical conditions. In the absence of inhalation toxicology study, the Panel is not in the position to establish the inhalation toxicity of the additive. The use of synthetic ATX-DMDS does not pose a significant additional risk to the environment compared with natural astaxanthin. ATX-DMDS is efficacious in colouring the flesh of salmonids and other fish. ATX-DMDS is an effective pigment for crustaceans at the proposed conditions of use.
PubMed: 32626207
DOI: 10.2903/j.efsa.2019.5920 -
Frontiers in Physiology 2017Polyploidy, the existence of cells containing more than one pair of chromosomes, is a well-known feature of mammalian hepatocytes. Polyploid hepatocytes are found either...
Polyploidy, the existence of cells containing more than one pair of chromosomes, is a well-known feature of mammalian hepatocytes. Polyploid hepatocytes are found either as cells with a single polyploid nucleus or as multinucleated cells with diploid or even polyploid nuclei. In this study, we evaluate the degree of polyploidy in the murine liver by accounting both DNA content and number of nuclei per cell. We demonstrate that mouse hepatocytes with diploid nuclei have distinct metabolic characteristics compared to cells with polyploid nuclei. In addition to strong differential gene expression, comprising metabolic as well as signaling compounds, we found a strongly decreased insulin binding of nuclear polyploid cells. Our observations were associated with nuclear ploidy but not with total ploidy within a cell. We therefore suggest ploidy of the nuclei as an new diversity factor of hepatocytes and hypothesize that hepatocytes with polyploid nuclei may have distinct biological functions than mono-nuclear ones. This diversity is independent from the well-known heterogeneity related to the cells' position along the porto-central liver-axis.
PubMed: 29163206
DOI: 10.3389/fphys.2017.00862 -
Biomedicines Feb 2015Activation of the hepatocyte growth factor/Met receptor is involved in muscle regeneration, through promotion of proliferation and inhibition of differentiation in...
Activation of the hepatocyte growth factor/Met receptor is involved in muscle regeneration, through promotion of proliferation and inhibition of differentiation in myogenic stem cells (MSCs). We previously described that the specific expression of an oncogenic version of the Met receptor (Tpr-Met) in terminally-differentiated skeletal muscle causes muscle wasting . Here, we induced Tpr-Met in differentiated myotube cultures derived from the transgenic mouse. These cultures showed a reduced protein level of myosin heavy chain (MyHC), increased phosphorylation of Erk1,2 MAPK, the formation of giant sacs of myonuclei and the collapse of elongated myotubes. Treatment of the cultures with an inhibitor of the MAPK kinase pathway or with an inhibitor of the proteasome increased the expression levels of MyHC. In addition, the inhibition of the MAPK kinase pathway prevented the formation of myosacs and myotube collapse. Finally, we showed that induction of Tpr-Met in primary myotubes was unable to produce endoreplication in their nuclei. In conclusion, our data indicate that multinucleated, fused myotubes may be forced to disassemble their contractile apparatus by the Tpr-Met oncogenic factor, but they resist the stimulus toward the reactivation of the cell cycle.
PubMed: 28536403
DOI: 10.3390/biomedicines3010124