Il-Hwa Hong

Cooperation of C/EBP family proteins and chromatin remodeling proteins is essential for termination of liver regeneration

Liver cancer is the fifth most common cancer. A highly invasive surgical resection of the liver tumor is the main approach used to eliminate the tumor. Mechanisms that terminate liver regeneration when the liver reaches the original size are not known. The aims of this work were to generate an animal model that fails to stop liver regeneration after surgical resections and elucidate mechanisms that are involved in termination of liver regeneration. Because epigenetic control of liver function has been previously implicated in the regulation of liver proliferation, we generated C/EBPα‐S193A knockin mice, which have alterations in formation of complexes of C/EBP family proteins with chromatin remodeling proteins. The C/EBPα‐S193A mice have altered liver morphology and altered liver function leading to changes of glucose metabolism and blood parameters. Examination of the proliferative capacity of C/EBPα‐S193A livers showed that livers of S193A mice have a higher rate of proliferation after birth, but stop proliferation at the age of 2 months. These animals have increased liver proliferation in response to liver surgery as well as carbon tetrachloride (CCl4)‐mediated injury. Importantly, livers of C/EBPα‐S193A mice fail to stop liver regeneration after surgery when livers reach the original, preresection, size. The failure of S193A livers to stop regeneration correlates with the epigenetic repression of key regulators of liver proliferation C/EBPα, p53, FXR, SIRT1, PGC1α, and TERT by C/EBPβ‐HDAC1 complexes. The C/EBPβ‐HDAC1 complexes also repress promoters of enzymes of glucose synthesis PEPCK and G6Pase. Conclusion: Proper cooperation of C/EBP and chromatin remodeling proteins is essential for the termination of liver regeneration after surgery and for maintenance of liver functions. (Hepatology 2015;61:315–325)

Age-associated change of C/EBP family proteins causes severe liver injury and acceleration of liver proliferation after CCl4 treatments.

Background: Older patients are more sensitive to drug-mediated development of liver disorders. Results: Age and CCl4 treatments change expression of C/EBP proteins leading to repression of key regulators of liver biology. Conclusion: The age-associated alterations of C/EBP proteins cause severe liver injury after CCl4 treatments. Significance: Understanding of mechanisms of age-associated severe liver injury is important for development of therapeutic approaches. The aged liver is more sensitive to the drug treatments and has a high probability of developing liver disorders such as fibrosis, cirrhosis, and cancer. Here we present mechanisms underlying age-associated severe liver injury and acceleration of liver proliferation after CCl4 treatments. We have examined liver response to CCl4 treatments using old WT mice and young C/EBPα-S193D knockin mice, which express an aged-like isoform of C/EBPα. Both animal models have altered chromatin structure as well as increased liver injury and proliferation after acute CCl4 treatments. We found that these age-related changes are associated with the repression of key regulators of liver biology: C/EBPα, Farnesoid X Receptor (FXR) and telomere reverse transcriptase (TERT). In quiescent livers of old WT and young S193D mice, the inhibition of TERT is mediated by HDAC1-C/EBPα complexes. After CCl4 treatments, TERT, C/EBPα and FXR are repressed by different mechanisms. These mechanisms include the increase of a dominant negative isoform, C/EBPβ-LIP, and subsequent repression of C/EBPα, FXR, and TERT promoters. C/EBPβ-LIP also disrupts Rb-E2F1 complexes in C/EBPα-S193D mice after CCl4 treatments. To examine if these alterations are involved in drug-mediated liver diseases, we performed chronic treatments of mice with CCl4. We found that C/EBPα-S193D mice developed fibrosis much more rapidly than WT mice. Thus, our data show that the age-associated alterations of C/EBP proteins create favorable conditions for the increased liver proliferation after CCl4 treatments and for development of drug-mediated liver diseases.

Effect of autologous platelet-rich plasma application on cutaneous wound healing in dogs.

This study was conducted to identify the effectiveness of platelet-rich plasma (PRP) and efficacy of intralesional injection as a method of application to acute cutaneous wounds in dogs. Healthy adult beagles (n = 3) were used in this study. Autologous PRP was separated from anticoagulant treated whole blood in three dogs. Cutaneous wounds were created and then treated by intralesional injection of PRP in the experimental group, while they were treated with saline in the control group on days 0, 2 and 4. The healing process was evaluated by gross examination throughout the experimental period and histologic examination on day 7, 14 and 21. In PRP treated wounds, the mean diameter was smaller and the wound closure rate was higher than in the control. Histological study revealed that PRP treated wounds showed more granulation formation and angiogenesis on day 7, and faster epithelialization, more granulation formation and collagen deposition were observed on day 14 than in control wounds. On day 21, collagen deposition and epithelialization were enhanced in PRP treated groups. Overall, PRP application showed beneficial effects in wound healing, and intralesional injection was useful for application of PRP and could be a good therapeutic option for wound management in dogs.

Smad3 Deficiency Ameliorates Hepatic Fibrogenesis through the Expression of Senescence Marker Protein-30, an Antioxidant-Related Protein

Smad3 is a key mediator of the transforming growth factor (TGF)-β1 signaling pathway that plays central role in inflammation and fibrosis. In present study, we evaluated the effect of Smad3 deficiency in Smad3−/− mice with carbon tetrachloride (CCl4)-induced liver fibrosis. The animals were received CCl4 or olive oil three times a week for 4 weeks. Histopathological analyses were performed to evaluate the fibrosis development in the mice. Alteration of protein expression controlled by Smad3 was examined using a proteomic analysis. CCl4-induced liver fibrosis was rarely detected in Smad3−/− mice compared to Smad3+/+. Proteomic analysis revealed that proteins related to antioxidant activities such as senescence marker protein-30 (SMP30), selenium-binding proteins (SP56) and glutathione S-transferases (GSTs) were up-regulated in Smad3−/− mice. Western blot analysis confirmed that SMP30 protein expression was increased in Smad3−/− mice. And SMP30 levels were decreased in CCl4-treated Smad3+/+ and Smad3−/− mice. These results indicate that Smad3 deficiency influences the proteins level related to antioxidant activities during early liver fibrosis. Thus, we suggest that Smad3 deteriorate hepatic injury by inhibitor of antioxidant proteins as well as mediator of TGF-β1 signaling.

Cardiorespiratory dose-response relationship of isoflurane in Cinereous vulture (Aegypius monachus) during spontaneous ventilation

Anesthesia is an inevitably important component of diagnosis and treatments examining the health condition of wild animals. Not only does anesthesia become an essential tool in minimizing stress of the patients and providing an opportunity to deliver accurate and safe procedures, but it also ensures the safety of the medical crew members. This study was conducted to investigate the dose-response cardiorespiratory effects of isoflurane during spontaneous ventilation in ten cinereous vultures. Each bird was administered isoflurane at initial concentration of 1.0, 1.5, 2.0, 2.5 and 3.0 and then an end-tidal isoflurane concentrations (ETiso) of 1.0% for an equilibration period of 15 min in the given order. At the end of the equilibration period, the direct blood pressure (BP), heart rate (HR), respiratory rate (RR) and end tidal CO2 partial pressure (PETCO2) were recorded, and blood gas analysis was performed. Increasing isoflurane concentrations during spontaneous ventilation led to dose-dependent increases in HR and PETCO2, with minimal changes in RR, decreased arterial BP and respiratory acidosis. Overall, isoflurane for anesthesia of spontaneously breathing cinereous vultures is a suitable choice for diagnostic or surgical procedures.

Maysin and Its Flavonoid Derivative from Centipedegrass Attenuates Amyloid Plaques by Inducting Humoral Immune Response with Th2 Skewed Cytokine Response in the Tg (APPswe, PS1dE9) Alzheimer’s Mouse Model

Alzheimer’s disease (AD) is a slow, progressive neurodegenerative disease and the most common type of dementia in the elderly. The etiology of AD and its underlying mechanism are still not clear. In a previous study, we found that an ethyl acetate extract of Centipedegrass (CG) (i.e., EA-CG) contained 4 types of Maysin derivatives, including Luteolin, Isoorientin, Rhamnosylisoorientin, and Derhamnosylmaysin, and showed protective effects against Amyloid beta (Aβ) by inhibiting oligomeric Aβ in cellular and in vitro models. Here, we examined the preventative effects of EA-CG treatment on the Aβ burden in the Tg (Mo/Hu APPswe PS1dE9) AD mouse model. We have investigated the EA-CG efficacy as novel anti-AD likely preventing amyloid plaques using immunofluorescence staining to visually analyze Aβ40/42 and fibril formation with Thioflavin-S or 6E10 which are the profile of immunoreactivity against epitope Aβ1–16 or neuritic plaque, the quantitation of humoral immune response against Aβ, and the inflammatory cytokine responses (Th1 and Th2) using ELISA and QRT-PCR. To minimize the toxicity of the extracted CG, we addressed the liver toxicity in response to the CG extract treatment in Tg mice using relevant markers, such as aspartate aminotransferase (AST)/ alanine aminotransferase (ALT) measurements in serum. The EA-CG extract significantly reduced the Aβ burden, the concentration of soluble Aβ40/42 protein, and fibril formation in the hippocampus and cortex of the Tg mice treated with EA-CG (50 mg/kg BW/day) for 6 months compared with the Tg mice treated with a normal diet. Additionally, the profile of anti-inflammatory cytokines revealed that the levels of Th2 (interleukin-4 (IL-4) and interleukin-10 (IL-10)) cytokines are more significantly increased than Th1 (interferon-γ (IFN-γ), interleukin-2(IL-2)) in the sera. These results suggest that the EA-CG fraction induces IL-4/IL-10-dependent anti-inflammatory cytokines (Th2) rather than pro-inflammatory cytokines (Th1), which are driven by IL-2/IFN-γ. With regard to the immune response, EA-CG induced an immunoglobulin IgG and IgM response against the EA-CG treatment in the Tg mice. Furthermore, EA-CG significantly ameliorated the level of soluble Aβ42 and Aβ40. Similarly, we observed that the fibril formation was also decreased by EA-CG treatment in the hippocampus and cortex after quantitative analysis with Thioflavin-S staining in the Tg brain tissues. Taken together, our findings suggested that Maysin and its derivative flavonoid compounds in the EA-CG fraction might be beneficial therapeutic treatments or alternative preventative measures to adjuvant for boosting humoral and cellular include immune response and anti-inflammation which may lead to amyloid plaque accumulation in Alzheimer’s patients’ brains.

Anti-rheumatoid arthritic effect of fermented Adlay and Achyranthes japonica Nakai on collagen-induced arthritis in mice

ABSTRACT Adlay (CL) has been used as food and medicinal plant, and its anti-inflammatory, anti-cancer and anti-allergic activities have been demonstrated. However, its anti-rheumatoid arthritic effect has not been evaluated. We evaluated the anti-rheumatoid arthritic activity of fermented CL (FCL) in vivo compared to fermented Achyranthes japonica Nakai (FAJN). The collagen-induced arthritis (CIA) mouse model was used, and clinical signs, histological examination, serum inflammatory and rheumatoid factors were analyzed. FCL and FAJN significantly reduced incidence of CIA, alleviated inflammation and joint destruction through inhibition of IL-1β and rheumatoid factors. In addition, they increased anti-oxidant enzyme activity such as superoxide dismutase (SOD) in the liver. Interestingly, ferulic acid was isolated from the FCL extract, which have anti-oxidant and anti-inflammatory activities. Moreover, the anti-rheumatoid arthritis (RA) effect of FCL was shown to be similar to or much better than that of FAJN. Therefore, our study suggests that FCL and FAJN are potential agents to alleviate RA.

Histopathological findings in wild Nutrias (Myocastor coypus) with Capillaria hepatica infection

Capillaria hepatica is a zoonotic nematode that uses rodents and other mammals as hosts, especially rats and mice, and causes hepatic granuloma and eventually fibrosis/cirrhosis. However, C. hepatica infection in nutria, a large semiaquatic rodent, has rarely been reported, and histopathologic features of the infection have not been described in detail. We conducted necropsy on 36 wild nutrias. Some animals were found to have milky spots, parasitic eggs and worms within hepatic microgranuloma involving central calcification with cell debris, macrophages, eosinophils and multinucleated giant cells (MGCs). Interestingly, the eggs were closely surrounded by MGCs and appeared to be destroyed without inducing further chronic changes. Based on microscopical examination, C. hepatica infection was diagnosed, and we describe its histopathological characteristics in wild nutrias.

A Case of Fascioliasis in A Wild Nutria, Myocastor coypus, in Republic of Korea

A total of 44 adult or juvenile nutrias were necropsied for disease survey. A large nodule was found in the liver of a nutria. The histopathological specimen of the hepatic nodule was microscopically examined, and sectional worms were found in the bile duct. The worms showed a tegument with spines, highly branches of vitelline glands and intestine. Finally, we histopathologically confirmed fascioliasis in a wild nutria. In the present study, a case of fascioliasis in a wild nutria is first confirmed in Korea.

Sebaceous cell differentiation in a canine oral papilloma

Papillomas caused by viral infection are well-known tumors in animals. Microscopic features typically include neoplastic epithelium with hyperkeratosis and koilocytes. An 8-y-old castrated male Shih Tzu dog was presented with a small exophytic mass on the external upper lip. The mass was diagnosed as a viral papilloma based on microscopic and immunohistochemical examination. Sebaceous cell differentiation was found in the neoplastic epithelium of the tumor, which is a rare finding in humans or animals.