• Applied Microscopy
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• v.40 no.2
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• pp.73-80
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• 2010

Liver regeneration is a result of highly coordinated proliferation of hepatocytes and nonparenchymal liver cells. Partial hepatectomy (PH) is the most often used stimulus to study liver regeneration because, compared with other methods that use hepatic toxins, it is not associated with the tissue injury and inflammation, and the initiation of the regenerative stimulus is precisely defined. Granulocyte macrophage-colony stimulating factor (GM-CSF), which is a cytokine able to regulate the proliferation and differentiation of epithelial cells, was first identified as the most potent mitogen for bone marrow. Particularly, rrhGM-CSF, which is highly glycosylated and sustained longer than any other types of GM-CSF in the blood circulation, was specifically produced from rice cell culture. In this experiment, effects of rrhGM-CSF administration were evaluated in the regenerating liver after 78% PH of rats. Morphological changes induced by PH were characterized by destroyed hepatocyte plate around the central vein and enlarged nuclear cytoplasmic ratio and increased hepatocytes with two nuclei. And then, proliferation of liver cells (parenchymal and nonparenchymal) and rearrangement of plates and lobules seemed to be carried out during liver regeneration. These alterations in the experimental group preceded those of the control. Since proliferating cell nuclear antigen (PCNA) is known to be a nuclear protein maximally elevated in the S phase of proliferating cells, the protein was used as a marker of liver regeneration after PH in rats. PCNA levels by western blot analysis and immunohistology were compared between the two groups. PCNA protein expression of two groups at 12 hr and 24 hr after injury showed similar pattern. The protein expression showed the peak at 3 days in both groups, however, the protein level of the experimental group was higher than that of the control. On immunohistochemical observations, the reaction product of PCNA was localized at the nuclei of proliferating cells and the positive reaction in experimental group at 3 days was clearly stronger than that in control group. The results by Western blotting and immunohistology for PCNA showed similar pattern in terms of the protein levels. In conclusion, rrhGM-CSF administration during liver regeneration after 78% PH accelerated breakdown and restoration of the hepatic plate and expression of PCNA. These results suggest that rrhGM-CSF might play an important role during liver regeneration in rats.

• Clinical and Experimental Reproductive Medicine
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• v.35 no.4
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• pp.247-265
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• 2008

Objectives: Many types of liver diseases can damage regenerative potential of mature hepatocytes, hepatic progenitor cells or oval cells. In such cases, a stem cell-based therapy can be an alternative therapeutic option. We examined whether human amnion-derived mesenchymal stem cells (HAM) and human umbilical cord-derived stem cells (HUC) could differentiate into hepatocyte-like cells as therapeutic cells for the liver diseases. Methods: HAM and HUC were isolated from the amnion and umbilical cord of the volunteers after a caesarean section with informed consent. In order to differentiate these cells into hepatocyte-like cells, cells were cultivated in hepatogenic medium using culture plates coated with fibronectin. Effects of hepatocyte growth factor, L-ascorbic acid 2-phosphate, insulin premixture fibroblast growth gactor 4, dimethylsulfoxide, oncostatin M and/or dexamethasone were examined on the hepatic differentiation. After differentiation, the cells were analyzed by RT-PCR, immunocytochemistry, immunoblotting, albumin ELISA, urea assay and periodic acid-schiffs staining. Results: Initial fibroblast-like appearance of HAM and HUC changed to a round shape during culture in the hepatogenic medium. However, in all hepatogenic conditions examined, HUC secreted more amounts of albumin or urea into medium than HAM. Expression of some of hepatocyte-specific genes increased and expression of new genes were observed in HUC following cultivation in hepatogenic medium. Results of immunocytochemistry and immunoblotting analyses demonstrated that HUC secreted albumin into the culture medium. PAS staining further demonstrated that HUC could store glycogen inside of the cells. Conclusions: Both HUC and HAM could differentiate into albumin-secreting, hepatocyte-like cells. Under the same hepatogenic conditions examined, HUC more efficiently differentiated into hepatocyte-like cells compared with the HAM. The results suggest that HUC and HAM could be used as sources of stem cells for the cell-based therapeutics such as in liver diseases.

• Journal of Aquaculture
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• v.6 no.2
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• pp.107-123
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• 1993

To define the effects of various levels $(0\~1.5\%)$ of dietary n-3HUFA on the physiological changes in the Korean rockfish, variations in blood variables and hepatocytes were studied. Biochemical serum analyses, lactate dehydrogenase (LDH) activity of the liver cytosol and ATPase activity of the liver microsomal membrane were also studied. The haematological values (red blood cell, hemoglobin, hematocrit, MCHC, MCV and MCH) were not significantly different in the experimental groups $(P\geq0.05)$. The total protein and glucose levels in the serum were affected by dietary n-3HUFA levels. These levels in groups fed n-3HUFA insufficient diets were significantly lower than those of n-3HUFA sufficient groups (P<0.05). Serum levels of total cholesterol, free cholesterol, glutamic pyruvic transaminase (GPT) and glutamic oxaloacetatic transaminase (GOT) showed significantly higher values in the fish fed n-3HUFA deficient diets (P<0.05). The LDH in the serum was dropped with increasing dietary n-3HUFA levels, but the LDH activity of the liver cytosol was elevated. Histologically, the hepatic cell in the fish fed n-3HUFA free diet was abnormal and showed a necrotic condition. $Ca^{2+}-ATPase$ activities of the liver microsomal membrane were significantly lower in the fish fed n-3HUFA deficient diets than in those fed n-3HUFA sufficient diets (p<0.005). These results suggested that the liver cell membrane was affected by dietary fatty acid compositions and cell membrane of the fish fed n-3HUFA insufficient diets showed abnormalities.

• Journal of Life Science
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• v.14 no.3
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• pp.375-384
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• 2004

Fibroblast growth factors (FGFs) are known to induce multiple functions in early development, including mesoderm formation, gastrulation movement and antero-posterior patterning. The induction of mesoderm from Xenopus presumptive ectoderm and the combination effect on inducing organs of bFGF(basic FGF) and HGF (Hepatocyte Growth Factor) were studied. Explants were cultured in the combined solution for 3 days to normal embryo arrive at St. 43. These effects on combined dose were examined by histological experiment and by immunohistochemical method. The concentrations of growth factors were tested in 0, 0.5, 1, 10 and also tested in 50 ng/ml of bFGF, and 0, 1, 10, 50 and 100ng/ml of HGF respectively. The synergistic effects were seen in the combined-dose of bFGF and HGF rather than in single dose. Various organs were differentiated and highest inducing effects were seen at the combined concentration of 1 ng/ml of bFGF and 10ng/ml of HGF, and at the concentration 10ng/ml of bFGF and 1 ng/ml of HGF. The bFGF induces various organs from cultured animal cap explants and the effects are time and dose-dependent. HGF is also a potent mitogen for renal tubular cells and for mature hepatocytes in primary culture. Eyes were developed in high percentage at the combined concentration of 1 and 10ng/ml of bFGF, and 1 and 10 ng/ml of HGF. From the induced eye and normal embryonic eye, RPE65 was commonly detected by monoclonal antibodies 40All and 25F5 and the localization of RPE65 was seen by AP reaction.

• Biomedical Science Letters
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• v.5 no.1
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• pp.85-93
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• 1999

Nitric oxide (NO) plays an important role in immunologic defense, and influences upon the functioning of secretory tissues and cells. It also exhibits cytotoxic/cytostatic activity as one of major operating effectors of the cellular immunity system. We investigated the effects of serum on the cell damages and NO production in the mouse liver cell line BNL CL.2 to establish the role of NO. We observed that, when BNL CL.2 cells were cultured in serum-free medium, they were induced to cell damage by the stimulation of IFN-$\gamma$ alone or IFN-$\gamma$ plus LPS. Serum-starved cells showed large amount of nitrite accumulation and NO synthase (NOS) expression in response to IFN-$\gamma$ alone in dose- and time- dependent manners, but serum-supplied cells did not The production of NO was blocked by protein tyrosine kinase (PTK) inhibitors, genistein and herbimycin. These results suggest that the deprivation of serum in the BNL CL.2 cell culture medium might primed with the cells to produce NO when the cells are triggered by IFN-$\gamma$ and the involvement of PTK signal transduction pathway in the expression of NOS gene in murine hepatocytes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1166-1173
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• 2014

This study investigated the detoxification effects of enzymatic hydrolysate from oyster on acetaminophen-induced toxicity using HepG-2 cells. Oyster hydrolysate was made with 1% Protamex and 1% Neutrase after treatment with transglutaminase (TGPN) or without (PN). Two types of oyster hydrolysate were added to human-derived HepG-2 hepatocytes damaged by acetaminophen, after which the survival rate of HepG-2 cell was measured. In addition, glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) activities in the culture media were evaluated. The survival rates of HepG-2 cells were $136.2{\pm}1.4%$ at $100{\mu}g/mL$ of TGPN and $179.6{\pm}3.8%$ at $200{\mu}g/mL$ of TGPN. These cell survival rates were higher compared to that of the negative control group ($60.7{\pm}3.2%$) treated only with acetaminophen. GOT activity was $38.3{\pm}0.2$ Karmen/mL in the negative control group, whereas it was $19.9{\pm}0.5$ for TGPN ($200{\mu}g/mL$) and $22.0{\pm}2.4$ Karmen/mL for PN ($200{\mu}g/mL$). GOT and GTP activities were shown to be dependent on TGPN concentration, and significant reduction in activities could be conformed. The detoxification efficacy of TGPN was higher compared to that of PN. These results suggest that oyster hydrolysate has potential as a healthy food or pro-drug for liver protection.