Juha Song

High animal fat intake enhances prostate cancer progression and reduces glutathione peroxidase 3 expression in early stages of TRAMP mice.

Prostate cancer is the most frequently diagnosed cancer in Western men, and more men have been diagnosed at younger ages in recent years. A high‐fat Western‐style diet is a known risk factor for prostate cancer and increases oxidative stress.

The First Case of Capillaria hepatica Infection in a Nutria (Myocastor coypus) in Korea

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.

First detection of West Nile virus in domestic pigeon in Korea

West Nile virus (WNV) is a mosquito-borne zoonotic pathogen that has spread throughout Europe and the United States. Recently, WNV spread to East and Southeast Asia, and great efforts have been made in South Korea to prevent the spread of WNV from neighboring countries. In this study, we diagnosed the first case of WNV in pigeons (Columba livia domestica) residing in cities using a competitive enzyme-linked immunosorbent assay and confirmed it with nested reverse transcription polymerase chain reaction analysis and sequencing. This is the first report to provide convincing evidence that WNV is present within South Korea.

Detection and Molecular Characterization of Cryptosporidium spp. from Wild Rodents and Insectivores in South Korea

In order to examine the prevalence of Cryptosporidium infection in wild rodents and insectivores of South Korea and to assess their potential role as a source of human cryptosporidiosis, a total of 199 wild rodents and insectivore specimens were collected from 10 regions of South Korea and screened for Cryptosporidium infection over a period of 2 years (2012-2013). A nested-PCR amplification of Cryptosporidium oocyst wall protein (COWP) gene fragment revealed an overall prevalence of 34.2% (68/199). The sequence analysis of 18S rRNA gene locus of Cryptosporidium was performed from the fecal and cecum samples that tested positive by COWP amplification PCR. As a result, we identified 4 species/genotypes; chipmunk genotype I, cervine genotype I, C. muris, and a new genotype which is closely related to the bear genotype. The new genotype isolated from 12 Apodemus agrarius and 2 Apodemus chejuensis was not previously identified as known species or genotype, and therefore, it is supposed to be a novel genotype. In addition, the host spectrum of Cryptosporidium was extended to A. agrarius and Crosidura lasiura, which had not been reported before. In this study, we found that the Korean wild rodents and insectivores were infected with various Cryptosporidium spp. with large intra-genotypic variationa, indicating that they may function as potential reservoirs transmitting zoonotic Cryptosporidium to livestock and humans.

Lactic Acid Upregulates VEGF Expression in Macrophages and Facilitates Choroidal Neovascularization

Purpose Lactic acid, the end product of glycolysis, has emerged as an immune-modulating metabolite in various diseases. In this study, we aimed to examine whether lactic acid contributes to the disease pathogenesis of choroidal neovascularization (CNV) and to investigate the role of macrophages in CNV pathogenesis. Methods CNV was induced by laser photocoagulation in C57BL/6J mice. Lactic acid concentration was measured in the RPE-choroid region. Macrophage infiltration and VEGF were quantified by flow cytometry. VEGF-positive areas and CNV lesions were measured by flat-mount immunofluorescence staining. To inhibit lactic acid uptake in vivo, alpha-cyano-4-hydroxycinnamic acid (α-CHC), a monocarboxylate transporter (MCT) blocker, was injected intravitreally 1 day after laser. VEGF productions were measured in ARPE-19, THP-1 cells, and human umbilical vein endothelial cells (HUVECs) by quantitative PCR and ELISA. Angiogenic activity of lactic acid-treated macrophages was assessed by HUVEC tube formation assay. Results Lactic acid was significantly increased in the RPE-choroid region of CNV-induced mice. Lactic acid upregulated VEGFA mRNA and VEGF protein expressions in THP-1 macrophages, but did not in ARPE-19 or HUVECs. THP-1 macrophages treated with lactic acid increased the angiogenesis of endothelial cells independent of MCT activity. Intravitreal injection of α-CHC substantially reduced the VEGF-positive area that colocalized with F4/80-positive macrophages. CNV lesions were also significantly reduced following α-CHC injection compared with vehicle-injected controls. Conclusions To our knowledge, these results show for the first time the role of lactic acid in facilitating neovascularization through macrophage-induced angiogenesis. We suggest that targeting macrophage metabolism can be a promising strategy for CNV treatment.

Data set in support of neurotoxicity of trimethyltin chloride by morphological and protein analysis

Trimethyltin chloride (TMT) is a neurotoxicant widely present in the aquatic environment. Chronic exposure of embryos to TMT for 4 days post-fertilization (dpf) elicited a concentration-related decrease in head & eye size and increase in axial malformation. In addition, Rohon-Beard sensory neurons and motor neurons showed decreased patterns of protein expression. These data coincide with previous research about the neurotoxicity of TMT on mRNA expression (Kim et al., 2016 [1]). These data demonstrates that TMT inhibits specific neurodevelopmental stages in zebrafish embryos and suggests a possible mechanism for the toxicity of TMT in vertebrate neurodevelopment. This paper contains data related to research concurrently published in Kim et al. (2016) [1].

Effect of caffeine on Alzheimer’s molecular factors in correlation with involved cell communication systems in developing zebrafish Danio rerio

Abstract Background: Epidemiological studies suggested that caffeine/coffee could be an effective therapeutic agent against Alzheimer disease (AD). The mechanism has not been well established; however, molecular genetic analyses suggest that many genes influence it. Methods: Using developing zebrafish (Danio rerio), we studied the regulatory effect of caffeine on AD molecular factors, APP, Psen1, Psen2, ApoE, and Sorl1, and on receptor expression of two cell communication systems involved in the disease, adenosine (AR) and dopamine receptors (DR). Results: All genes are already expressed at early developmental stages. No morphological changes were found at tested concentrations and control. Caffeine significantly down-regulated the expression of all AD tested genes at 24 h post-fertilization (hpf) and APP, Sorl1, and Psen1 at 96 and 168 hpf. A2aa and A2ab receptors have higher affinity for caffeine than A2b. Significant down-regulation occurred in A2b at 168 hpf in both concentrations. Caffeine blocked the expression of drd2a and drd2c at 24 hpf but significantly stimulated the expression at 96 and 168 hpf. Conclusions: Zebrafish is a promising organism in studying AD at the molecular level because all tested factors are already expressed at early developmental stages. Caffeine has a regulatory effect on all tested genes and may protect against the disease via amyloid pathway as well as AR and DR.