Liver Disease Prevention and Treatment Research Foundation

Taipei, Taiwan

Liver Disease Prevention and Treatment Research Foundation

Taipei, Taiwan
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Wu C.-H.,National Taiwan University | Chen Y.-J.,National Taiwan University | Wang M.-H.,National Taiwan University | Chiou L.-L.,Liver Disease Prevention and Treatment Research Foundation | And 4 more authors.
PLoS ONE | Year: 2017

Axolotls have amazing ability to regenerate their lost limbs. Our previous works showed that after amputation the remnant muscle ends remained at their original location whilst sending satellite cells into the regenerating parts to develop into early muscle fibers in the late differentiation stage. The parental and the newly formed muscle fibers were not connected until very late stage. The present study used non-invasive diffusion tensor imaging (DTI) to monitor weekly axolotl upper arm muscles after amputation of their upper arms. DTI tractography showed that the regenerating muscle fibers became visible at 9-wpa (weeks post amputation), but a gap was observed between the regenerating and parental muscles. The gap was filled at 10-wpa, indicating reconnection of the fibers of both muscles. This was confirmed by histology. The DTI results indicate that 23% of the muscle fibers were reconnected at 10-wpa. In conclusion, DTI can be used to visualize axolotls' skeletal muscles and the results of muscle reconnection were in accordance with our previous findings. This non-invasive technique will allow researchers to identify the timeframe in which muscle fiber reconnection takes place and thus enable the study of the mechanisms underlying this reconnection. ©2017 Wu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Lee H.-C.,National Taiwan University | Lu P.-N.,National Taiwan University | Lu P.-N.,Liver Disease Prevention and Treatment Research Foundation | Huang H.-L.,National Taiwan University | And 5 more authors.
PLoS ONE | Year: 2014

Reliable animal models are invaluable for monitoring the extent of pollution in the aquatic environment. In this study, we demonstrated the potential of huORFZ, a novel transgenic zebrafish line that harbors a human upstream open reading frame of the chop gene fused with GFP reporter, as an animal model for monitoring environmental pollutants and stress-related cellular processes. When huORFZ embryos were kept under normal condition, no leaked GFP signal could be detected. When treated with hazardous chemicals, including heavy metals and endocrine-disrupting chemicals near their sublethal concentrations (LC50), huORFZ embryos exhibited different tissue-specific GFP expression patterns. For further analysis, copper (Cu2+), cadmium (Cd 2+) and Chlorpyrifos were applied. Cu2+ triggered GFP responses in skin and muscle, whereas Cd2+ treatment triggered GFP responses in skin, olfactory epithelium and pronephric ducts. Moreover, fluorescence intensity, as exhibited by huORFZ embryos, was dose-dependent. After surviving treated embryos were returned to normal condition, survival rates, as well as TUNEL signals, returned to pretreatment levels with no significant morphological defects observed. Such results indicated the reversibility of treatment conditions used in this study, as long as embryos survived such conditions. Notably, GFP signals decreased along with recovery, suggesting that GFP signaling of huORFZ embryos likely reflected the overall physiological condition of the individual. To examine the performance of the huORFZ line under real-world conditions, we placed huORFZ embryos in different river water samples. We found that the huORFZ embryos correctly detected the presence of various kinds of pollutants. Based on these findings, we concluded that such uORFchop-based system can be integrated into a first-line water alarm system monitoring the discharge of hazardous pollutants. © 2014 Lee et al.

Chiang T.-S.,National Taiwan University | Yang K.-C.,Taipei Medical University | Zheng S.-K.,National Taiwan University Hospital | Chiou L.-L.,Liver Disease Prevention and Treatment Research Foundation | And 6 more authors.
Biomaterials | Year: 2012

A reliable, reproducible, and convenient in vitro platform for drug metabolism determination and toxicity prediction is of tremendous value but still lacking. In the present study, a collection of 24 hepatic transcription factors and nuclear receptors in different combinations were surveyed, and 10 among them were finally selected to induce the expression and enzyme activities of cytochrome P450 (CYP) 3A4, 1B1, and 2C9 in human dermal fibroblasts (HDFs). The expression and activities of these CYPs in the induced HDFs were higher than those in commonly used hepatoma cell lines. High CYP expression and activities could be further enhanced by culturing the induced HDFs either as spheroids or into several kinds of scaffolds, particularly the tri-copolymer scaffold composed of gelatin, chondroitin and hyaluronan. More strikingly, there showed a synergistic effect of seeding and culturing the spheroids into the tri-copolymer scaffold. Scanning electron microscopy and confocal microscopy disclosed well accommodation of these spheroids inside the scaffolds and displayed a high survival rate. Moreover, the spheroid/scaffold constructs could metabolize an anti-hypertension drug nifedipine into oxidized nifedipine, showing their applicability in studying drug metabolism. This study presents a strategy to induce the expression and enzyme activities of critical CYPs in HDFs, and may have potential to establish an in vitro platform to study drug metabolism and to predict the possible human risk of drug toxicity. © 2012 Elsevier Ltd.

Li F.-C.,National Taiwan University | Huang G.-T.,National Taiwan University Hospital | Lin C.-J.,National Taiwan University | Wang S.-S.,National Taiwan University | And 8 more authors.
Cell Death and Disease | Year: 2011

Morphological changes of hepatocyte death have so far only been described on cells in culture or in tissue sections. Using a high-resolution and high-magnification multiphoton microscopic system, we recorded in living mice serial changes of acetaminophen (APAP)-induced hepatocyte necrosis in relevance to metabolism of a fluorogenic bile solute. Initial changes of hepatocyte injury included basal membrane disruption and loss of mitochondrial membrane potential. An overwhelming event of rupture at adjacent apical membrane resulting in flooding of bile into these hepatocytes might ensue. Belbs formed on basal membrane and then dislodged into the sinusoid circulation. Transmission electron microscopy disclosed a necrotic hepatocyte depicting well the changes after apical membrane rupture and bile flooding. Administration of the antidote N-acetylcysteine dramatically reduced the occurrence of apical membrane rupture. The present results demonstrated a hidden but critical step of apical membrane rupture leading to irreversible APAP-induced hepatocyte injury. © 2011 Macmillan Publishers Limited All rights reserved.

PubMed | China Medical University at Taichung, Liver Disease Prevention and Treatment Research Foundation and National Taiwan University
Type: Journal Article | Journal: Obesity research & clinical practice | Year: 2013

Significant hepatitis B viral load (10,000 copies/mL) was established to increase risk of advanced liver diseases. The aim of this study was to explore the metabolic risk factors for significant hepatitis B viral load. A campus-based cohort consisting of 146 participants of chronic hepatitis B virus (HBV) infection in Northern Taiwan was investigated in 2009. Clinical profiles including serum levels of deoxyribonucleic acid of hepatitis B virus (HBV DNA) were collected. Hepatitis B e antigen (HBeAg) serostatus, high alanine aminotransferase level, body mass index (BMI) ranges, and insulin resistance were related to significant HBV DNA levels in univariate analysis. Compared to individuals with BMI 23-24.9 kg/m(2) in multivariate analysis, those with BMI 25 kg/m(2) (OR = 3.86, 95% CI = 1.38-10.8, P = 0.010) and those with BMI <23 kg/m(2) (OR = 4.47, 95% CI = 1.32-15.2, P = 0.016) were at higher risk for significant HBV DNA levels. This phenomenon was also manifest in HBeAg seronegatives, who contributed to a majority of significant viral load in our study. Furthermore, insulin resistance and BMI 25 kg/m(2) had positive additive effects on significant HBV DNA levels (adjusted OR = 9.34, 95% CI = 1.74-50.3, P = 0.009). In conclusion, having certain BMI ranges (BMI 25 kg/m(2) or BMI <23 kg/m(2)) could be a risk factor of significant HBV DNA levels.:

PubMed | Liver Disease Prevention and Treatment Research Foundation, National Taiwan University and National Taiwan University Hospital
Type: | Journal: Journal of morphology | Year: 2016

Axolotls (Ambystoma mexicanum) may heal their skin wounds scar-free in both paedomorphs and metamorphs. In previous studies on small punch skin wounds, rapid re-epithelialisation was noted in these two axolotl morphs. However, large wound size in mammals may affect wound healing. In this study, large circumferential full thickness excision wounds on the hind limbs were created on juvenile paedomorphic and metamorphic axolotls. The results showed re-epithelialisation was more quickly initiated in paedomorphs than in metamorphs after wounding. The migrating rate of epidermis on the wound bed was faster in paedomorphs than in metamorphs and thus completion of re-epithelialisation was faster in paedomorphs than in metamorphs. Within these re-epithelialisation periods, neither basement membrane nor dermis was reformed. Epidermal cell proliferation was detected by EdU-labelling technique. In the normal unwounded skin, epidermal proliferation rate was higher in paedomorphs than in metamorphs. After wounding, the epidermal proliferation rate was significantly lower in the migrating front on the wound bed than in the normal skin in paedomorphs. The EdU-labelling rate between normal skin and migration front was not different in metamorphs. Lacking of more proliferating epidermal cells on the wound bed indicated that the new epidermis here derived rather from migrating epidermal cells than from cell proliferation in situ. In conclusion, re-epithelialisation in the large wound might be fully completed in both morphs despite it was initiated earlier and with faster rate in paedomorphs than in metamorphs. The new epidermis on the wound bed derived mainly from cell migration than by cell proliferation in the re-epithelialisation period. J. Morphol., 2016. 2016 Wiley Periodicals, Inc.

PubMed | Liver Disease Prevention and Treatment Research Foundation and National Taiwan University
Type: Journal Article | Journal: PloS one | Year: 2015

An appropriate liver-specific progenitor cell marker is a stepping stone in liver regenerative medicine. Here, we report brain isoform glycogen phosphorylase (GPBB) as a novel liver progenitor cell marker. GPBB was identified in a protein complex precipitated by a monoclonal antibody Ligab generated from a rat liver progenitor cell line Lig-8. Immunoblotting results show that GPBB was expressed in two liver progenitor cell lines Lig-8 and WB-F344. The levels of GPBB expression decreased in the WB-F344 cells under sodium butyrate (SB)-induced cell differentiation, consistent with roles of GPBB as a liver progenitor cell marker. Short hairpin RNA (shRNA)-mediated GPBB knockdown followed by glucose deprivation test shows that GPBB aids in liver progenitor cell survival under low glucose conditions. Furthermore, shRNA-mediated GPBB knockdown followed by SB-induced cell differentiation shows that reducing GPBB expression delayed liver progenitor cell differentiation. We conclude that GPBB is a novel liver progenitor cell marker, which facilitates liver progenitor cell survival under low glucose conditions and cell differentiation.

PubMed | Liver Disease Prevention and Treatment Research Foundation, Clinical Trial Center, U.S. National Cancer Institute and National Taiwan University Hospital
Type: | Journal: Scientific reports | Year: 2015

We previously demonstrated that the enhancer of rudimentary homolog (ERH) gene is required for the expression of multiple cell cycle and DNA damage response (DDR) genes. The present study investigated the role of ERH and its target DNA damage repair genes in hepatocellular carcinoma cells. We observed positive correlation between ERH and ataxia telangiectasia and Rad3 related (ATR) expression in liver tissues. Expression of ERH, ATR as well as checkpoint kinase 1 (CHK1) were higher in HCCs than in normal liver tissues. Knocking-down ERH augmented ultraviolet light induced DNA damage in HepG2 cells. ATR protein level is reduced upon ERH depletion as a result of defect in the splicing of ATR mRNA. Consequently, the ATR effector kinase Chk1 failed to be phosphorylated upon ultraviolet light or hydroxyurea treatment in ERH knocked-down HepG2 cells. Finally, we observed Chk1 inhibitor AZD7762 enhanced the effect of doxorubicin on inhibiting growth of HCC cells in vitro and in vivo. This study suggested that ERH regulates the splicing of the DNA damage response proteins ATR in HCC cells, and targeting DNA damage response by Chk1 inhibitor augments chemotherapy to treat HCC cells.

PubMed | Liver Disease Prevention and Treatment Research Foundation, National Taiwan University and National Taiwan University Hospital
Type: Journal Article | Journal: PloS one | Year: 2015

Although still debated, limb regeneration in salamanders is thought to depend on the dedifferentiation of remnant tissue occurring early after amputation and generating the progenitor cells that initiate regeneration. This dedifferentiation has been demonstrated previously by showing the fragmentation of muscle fibers into mononucleated cells and by revealing the contribution of mature muscle fibers to the regenerates by using lineage-tracing studies. Here, we provide additional evidence of dedifferentiation by showing that Pax7 (paired-box protein-7) transcripts are expressed at the ends of remnant muscle fibers in axolotls by using in situ hybridization and by demonstrating the presence of Pax7+ muscle-fiber nuclei in the early bud and mid-bud stages by means of immunohistochemical staining. During the course of regeneration, the remnant muscles did not progress; instead, muscle progenitors migrated out from the remnants and proliferated and differentiated in the new tissues at an early stage of differentiation. The regenerating muscles and remnant muscles were largely disconnected, and this left a gap between them until extremely late in the late stage of differentiation, at which point the new and old muscles connected together. Notably, Pax7 transcripts were detected in the regions of muscles that faced these gaps; thus, Pax7 expression might indicate dedifferentiation in the remnant-muscle ends and partial differentiation in the regenerating muscles. The roles of this long-duration dedifferentiation in the remnants remain unknown. However, the results presented here could support the hypothesis that long-duration muscle dedifferentiation facilitates the connection and fusion between the new and old muscles that are both in an immature state; this is because immature Pax7+ myoblasts readily fuse during developmental myogenesis.

PubMed | Liver Disease Prevention and Treatment Research Foundation, National Taiwan University and National Taiwan University Hospital
Type: | Journal: BioMed research international | Year: 2015

Urodele amphibians (Ambystoma mexicanum), unique among vertebrates, can regenerate appendages and other body parts entirely and functionally through a scar-free healing process. The wound epithelium covering the amputated or damaged site forms early and is essential for initiating the subsequent regenerative steps. However, the molecular mechanism through which the wound reepithelializes during regeneration remains unclear. In this study, we developed an in vitro culture system that mimics an in vivo wound healing process; the biomechanical properties in the system were precisely defined and manipulated. Skin explants that were cultured on 2 to 50kPa collagen-coated substrates rapidly reepithelialized within 10 to 15h; however, in harder (1GPa) and other extracellular matrices (tenascin-, fibronectin-, and laminin-coated environments), the wound epithelium moved slowly. Furthermore, the reepithelialization rate of skin explants from metamorphic axolotls cultured on a polystyrene plate (1GPa) increased substantially. These findings afford new insights and can facilitate investigating wound epithelium formation during early regeneration using biochemical and mechanical techniques.

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