Teratogenicity and brain aromatase-induction of monosodium glutamate in estrogen-responsive mosaic transgenic zebra fish Danio rerio

Monosodium glutamate (MSG) has been used as a flavor enhancer for decades. It has various teratogenicity effects on tested animals but has not been examined in zebra fish model to date. This experiment was conducted to study the teratogenic effects of MSG on wild-type zebra fish embryos and also to study the estrogenic potential of MSG on the transient zebrafish embryos with a brain aromatase-based reporter gene. Different concentrations of MSG (0, 10, 50 and 100 μg/ml) were tested. Wild-type and transient embryos were exposed to the solutions at about 2 h post fertilization (hpf). Hatching and survival decreased in all treatments with significant difference (p < 0.05) at 50 and 100 μg/ml concentrations with control. Stunted skeletal structure was observed at 100 μg/ml treatment. At 96 hpf, MSG induced enhanced green fluorescence protein (EGFP) expression in the olfactory bulb at 100 μg/ml treatment. Various malformations were found in all treatments. The current results demonstrate that MSG or MSG-containing foods may harm the human offspring if they take it in a high dose. MSG in high concentration may disrupt the endocrine function. Zebra fish embryo with a brain aromatase-based reporter gene is a good model for the detection of estrogenic potential of any controversial chemical.Keywords: Monosodium glutamate (MSG), teratogenicity, aromatase, embryos, zebra fis

Detection of sarcocystic infection in a wild rodent (Apodemus agrarius chejuensis) captured on Jeju island

Sarcocystis spp is a causative agent of sarcocystosis. They have a characteristic life cycle infecting both prey and predator. Sarcocystis can cause myositis, atrophy of the adjacent cells and abortion in cattle. In mice, sarcocystosis causes mild cellular reactions without clinical disease. Severe haemorrhage and abortion were also reported. For monitoring the disease in wild rodents of the Korean peninsula, we captured Apodemus agrarius chejuensis on Jeju island and examined the specimen histopathologically. Intramuscular cysts were found and diagnosed as Sarcocystis. Sarcocystic infection has been reported in worldwide. There have been many reported infections in cattle and pigs in Korea. To our knowledge, this is the first report of Sarcocystis in Apodemus agrarius chejuensis captured in Korea

Wirkung von Koffein auf die molekularen Faktoren der Alzheimer-Krankheit in Korrelation mit den beteiligten Zellkommunikationssystemen bei der Entwicklung von Zebrafisch Danio rerio

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. A(2aa) and A(2ab) receptors have higher affinity for caffeine than A(2b). Significant down-regulation occurred in A(2b) at 168 hpf in both concentrations. Caffeine blocked the expression of drd(2a) and drd(2c) 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.N

Adiaspiromycosis of an Apodemus agrarius captured wild rodent in Korea

Adiaspiromycosis is caused by pulmonary infection with Emmonsia. Inhalated spores of Emmonsia cause asymptomatic infection to necrogranulomatous pneumonia, depending on the burden of adiaspore and host immunity. For disease monitoring of wild rodents captured on Jeju Island in Korea, we examined the lung tissue of wild rodents histopathologically. Spores composed of thick three-layered walls were found following histopathological examination and were diagnosed as adiaspiromycosis. Adiaspiromycosis has been found in mammals in many parts of the world. To our knowledge, this is the first report of adiaspiromycosis of an Apodemus agrarius captured in Korea.N

Exposure time to caffeine affects heartbeat and cell damage-related gene expression of zebrafish Danio rerio embryos at early developmental stages

Caffeine is white crystalline xanthine alkaloid that is naturally found in some plants and can be produced synthetically. It has various biological effects, especially during pregnancy and lactation. We studied the effect of caffeine on heartbeat, survival and the expression of cell damage related genes, including oxidative stress (HSP70), mitochondrial metabolism (Cyclin G1) and apoptosis (Bax and Bcl2), at early developmental stages of zebrafish embryos. We used 100 mu m concentration based on the absence of locomotor effects. Neither significant mortality nor morphological changes were detected. We monitored hatching at 48h post-fertilization (hpf) to 96hpf. At 60 and 72hpf, hatching decreased significantly (P<0.05); however, the overall hatching rate at 96hpf was 94% in control and 93% in caffeine treatment with no significant difference (P>0.05). Heartbeats per minute were 110, 110 and 112 in control at 48, 72 and 96hpf, respectively. Caffeine significantly increased heartbeat - 122 and 136 at 72 and 96hpf, respectively. Quantitative RT-PCR showed significant up-regulation after caffeine exposure in HSP70 at 72hpf; in Cyclin G1 at 24, 48 and 72hpf; and in Bax at 48 and 72hpf. Significant down-regulation was found in Bcl2 at 48 and 72hpf. The Bax/Bcl2 ratio increased significantly at 48 and 72hpf. We conclude that increasing exposure time to caffeine stimulates oxidative stress and may trigger apoptosis via a mitochondrial-dependent pathway. Also caffeine increases heartbeat from early phases of development without affecting the morphology and survival but delays hatching. Use of caffeine during pregnancy and lactation may harm the fetus by affecting the expression of cell-damage related genes. Copyright (c) 2012 John Wiley & Sons, Ltd.N

Effect of fluorescent whitening agent on the transcription of cell damage-related genes in zebrafish embryos

7-Diethylamino-4-methylcoumarin (DEMC) is a fluorescent whitening agent (FWAs). There have been some studies on DEMC's protective effects against biological activity but there are few papers about the in vivo toxicity of DEMC. In this study, we used wild-type zebrafish embryos 3?days post fertilization (dpf). Test solutions with DEMC concentrations were negative control (without vehicle), 0 (with vehicle, 0.01% v/v ethanol), 0.25, 0.5, 0.75, 1.0, 1.25, 1.5 and 2?ppm. Embryos and larvae were counted for survival rate and hatching rate. Heart rates were also counted at 2.5 and 3.0?dpf. At 3.0?dpf, quantitative RT-PCR was performed with some samples (0, 0.25, 0.75 and 1.25?ppm) to determine the toxic effect to DEMC by detecting the expression levels of toxic-responsive genes. We used 11 genes, which included oxidative stress-related genes [sod(Mn), sod(Cu,Zn) and hsp70], mitochondrial metabolism-related genes (coxI, pyc, cyt and cyclinG1) and apoptosis-related genes (c-jun, bcl2, bax and p53). High-concentration DEMC-treated groups showed significant different survival rate, hatching rate and heart rate compared with low-concentration DEMC-treated groups. The LC50 of this chemical, 0.959?ppm, was calculated. We also confirmed that some genes in the DEMC exposure groups showed significantly up-regulations in expression levels compared with control groups. We concluded that the fluorescence agent, DEMC, has possible developmental toxicities and alteration effect of gene expression, which are related to oxidative stress, mitochondrial metabolism and apoptosis in zebrafish embryos. Copyright (c) 2011 John Wiley & Sons, Ltd.N

Detection and Molecular Characterization of <i>Cryptosporidium</i> 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

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.Y

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

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. A(2aa) and A(2ab) receptors have higher affinity for caffeine than A(2b). Significant down-regulation occurred in A(2b) at 168 hpf in both concentrations. Caffeine blocked the expression of drd(2a) and drd(2c) 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.N