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7
result(s) for
"Cheong, Seung-A"
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Knockout rat models mimicking human atherosclerosis created by Cpf1-mediated gene targeting
2019
The rat is a time-honored traditional experimental model animal, but its use is limited due to the difficulty of genetic modification. Although engineered endonucleases enable us to manipulate the rat genome, it is not known whether the newly identified endonuclease Cpf1 system is applicable to rats. Here we report the first application of CRISPR-Cpf1 in rats and investigate whether
Apoe
knockout rat can be used as an atherosclerosis model. We generated
Apoe-
and/or
Ldlr
-deficient rats via CRISPR-Cpf1 system, characterized by high efficiency, successful germline transmission, multiple gene targeting capacity, and minimal off-target effect. The resulting
Apoe
knockout rats displayed hyperlipidemia and aortic lesions. In partially ligated carotid arteries of rats and mice fed with high-fat diet, in contrast to
Apoe
knockout mice showing atherosclerotic lesions,
Apoe
knockout rats showed only adventitial immune infiltrates comprising T lymphocytes and mainly macrophages with no plaque. In addition, adventitial macrophage progenitor cells (AMPCs) were more abundant in
Apoe
knockout rats than in mice. Our data suggest that the Cpf1 system can target single or multiple genes efficiently and specifically in rats with genetic heritability and that
Apoe
knockout rats may help understand initial-stage atherosclerosis.
Journal Article
Progesterone receptor membrane component 1 is required for mammary gland development
2020
The physiological functions of progesterone (P4) in female reproductive organs including the mammary glands are mediated via the progesterone receptor (PR), but not all P4 functions can be explained by PR-mediated signaling. Progesterone receptor membrane component 1 (PGRMC1), a potential mediator of P4 actions, plays an important role in the ovary and uterus in maintaining female fertility and pregnancy, but its function in mammary glands has not been elucidated. This study investigated the role of PGRMC1 in mouse mammary gland development. Unlike in the uterus, exogenous estrogen (E2) and/or P4 did not alter PGRMC1 expression in the mammary gland, and Pgrmc1-knockout (KO) mice displayed reduced ductal elongation and side branching in response to hormone treatment. During pregnancy, PGRMC1 was expressed within both the luminal and basal epithelium and gradually increased with gestation and decreased rapidly after parturition. Moreover, although lactogenic capacity was normal after parturition, Pgrmc1 KO resulted in defective mammary gland development from puberty until midpregnancy, while the expression of PR and its target genes was not significantly different between wild-type and Pgrmc1-KO mammary gland. These data suggest that PGRMC1 is essential for mammary gland development during puberty and pregnancy in a PR-independent manner. Summary sentence Loss of PGRMC1, a potential mediator of progesterone, results in defective mammary gland development during puberty and gestation period.
Journal Article
PIBF1 regulates trophoblast syncytialization and promotes cardiovascular development
2024
Proper placental development in early pregnancy ensures a positive outcome later on. The developmental relationship between the placenta and embryonic organs, such as the heart, is crucial for a normal pregnancy. However, the mechanism through which the placenta influences the development of embryonic organs remains unclear. Trophoblasts fuse to form multinucleated syncytiotrophoblasts (SynT), which primarily make up the placental materno-fetal interface. We discovered that endogenous progesterone immunomodulatory binding factor 1 (PIBF1) is vital for trophoblast differentiation and fusion into SynT in humans and mice. PIBF1 facilitates communication between SynT and adjacent vascular cells, promoting vascular network development in the primary placenta. This process affected the early development of the embryonic cardiovascular system in mice. Moreover, in vitro experiments showed that PIBF1 promotes the development of cardiovascular characteristics in heart organoids. Our findings show how SynTs organize the barrier and imply their possible roles in supporting embryogenesis, including cardiovascular development. SynT-derived factors and SynT within the placenta may play critical roles in ensuring proper organogenesis of other organs in the embryo.
The genetic link between placenta function and congenital heart defects has been established, though the cellular mechanisms underlying this connection is less clear. Here they show that PIBF1 regulates syncytiotrophoblast fusion and that loss of PIBF1 also negatively impacts heart development, providing a potential link between the development of these two organs.
Journal Article
Lipid signatures reflect the function of the murine primary placentation
2022
The placenta regulates maternal-fetal communication, and its defect leads to significant pregnancy complications. The maternal and embryonic circulations are primitively connected in early placentation, but the function of the placenta during this developmentally essential period is relatively unknown. We thus performed a comparative proteomic analysis of the placenta before and after primary placentation and found that the metabolism and transport of lipids were characteristically activated in this period. The placental fatty acid (FA) carriers in specific placental compartments were upregulated according to gestational age, and metabolomic analysis also showed that the placental transport of FAs increased in a time-dependent manner. Further analysis of two mutant mice models with embryonic lethality revealed that lipid-related signatures could reflect the functional state of the placenta. Our findings highlight the importance of the nutrient transport function of the primary placenta in the early gestational period and the role of lipids in embryonic development. Summary Sentence The placenta is activated characteristically in terms of lipid transport during primary placentation, and the lipid-related signatures closely reflect the functional state of the placenta.
Journal Article
Improvement in the blastocyst quality and efficiency of putative embryonic stem cell line derivation from porcine embryos produced in vitro using a novel culturing system
by
KWAK, SEONG-SUNG
,
HYUN, SANG-HWAN
,
CHEONG, SEUNG A
in
Animal models
,
Animals
,
Blastocyst - cytology
2015
Porcine embryonic stem cells (pESCs) have great potential for application in translational biomedical research, including xenotransplantation and disease models. Obtaining high-quality blastocysts is the most important factor in the isolation and colonization of primary ESCs and the establishment of ESC lines. In pigs, in vitro-derived blastocysts have a limited cell number compared to in vivo-derived blastocysts and show an indefinite inner cell mass, which may result in failure to establish pESC lines. In the present study, the effects of resveratrol (RES), granulocyte-macrophage colony stimulating factor (GM-CSF) and β-mercaptoethanol (β-ME) on the quality of blastocysts and the efficiency of colony derivation were investigated for the establishment of ESCs. A novel culturing system was developed in which 2 µM RES was added to the oocyte in vitro maturation (IVM) medium, and 10 ng/ml pGM-CSF and 10 µM β-ME were added to embryo in vitro culture (IVC) medium. This novel system showed significantly more parthenogenetic activation (PA) blastocysts (54.5±1.8% vs. 43.4±1.2%; P<0.05) and in vitro fertilization (IVF) blastocysts (36.9±3.3% vs. 26.2±2.9%; P<0.06) at day seven as compared with that in the control system. The PA and IVF blastocysts from the novel system showed a significantly greater hatching rate (P<0.05) and greater cell numbers (55.1±2.0 vs. 45.6±2.0; P<0.05 and 78.9±6.8 vs. 58.5±7.2; P<0.06, for PA and IVF, respectively) at day seven compared to that in the control system. After seeding on feeder cells, the PA blastocysts produced by the novel system showed a significantly increased rate of attachment (28.8±3.9% vs. 17.2±2.4%; P<0.062). Finally, two putative pESC lines from PA embryos produced by the novel system and one by the control system were established. In conclusion, the novel system improved blastocyst quality and increased the derivation efficiency of putative pESC lines from porcine PA and IVF embryos produced in vitro.
Journal Article
Development and Validation of a Model to Predict Advanced Fibrosis in Chronic Hepatitis B Virus-Infected Patients with High Viral Load and Normal or Minimally Raised ALT
2011
Background/Aims
Treating a group of chronic hepatitis B virus (HBV)-infected patients with high viral load and advanced fibrosis or cirrhosis, regardless of their serum alanine aminotransferase (ALT) levels, is recommended. The aim of this study was to derive and validate a model to predict advanced fibrosis in a cohort of patients with viral replication and normal or minimally raised ALT [ALT < 2 × upper normal limit (UNL)].
Methods
Information was collected from 124 patients who underwent liver biopsy. The diagnostic value of predictors was judged using multivariate logistic modeling and area under the receiver operating characteristic curves (ROC area).
Results
Advanced fibrosis (F3 or F4 on METAVIR scoring schema) was diagnosed in 45.7% (95% CI, 34–57.4%) of the patients of the derivation set (70 patients) and in 37% (95% CI, 24.2–49.9%) of the validation set (54 patients). In the derivation set, age and aspartate aminotransferase (AST) were independent clinical predictors of advanced fibrosis. The ROC areas of this Age–AST model were 0.8 (95% CI, 0.7–0.9) in the derivation set and 0.82 (95% CI, 0.71–0.93) in the validation set, respectively. Without missing a single case, this model identified 11 patients (20%) without advanced fibrosis in the validation set.
Conclusions
A substantial proportion of patients with high viral load and ALT < 2 × UNL have advanced fibrosis. A simple model including age and AST is an easily applicable tool for physicians to guide their decisions on whether or not to perform liver biopsy in individual patients.
Journal Article