• Asian-Australasian Journal of Animal Sciences
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• v.12 no.5
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• pp.695-701
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• 1999

The hypothalamus is the classic site of synthesis of arginine vasotocin as neurohypophyseal hormone in the chicken. However, high concentrations of arginine vasotocin were also measured in ovarian tissues by radioimmunoassay. At first, we observed specific positive signal of mRNA encoding AVT in the hypothalamus by Northern hybridization. However, we could not find any specific bands in ovarian and uterine tissues. For evidence of transcription of the arginine vasotocin gene ingonadal tissues of the chicken, this study has applied the polymerase chain reaction as a highly sensitive assay. The hypothalamus, the four largest preovulatory ovarian follicles and the shell gland (uterus) were collected at 4 h and 20 h before oviposition. The ovarian follicular tissues were separated into granulose theca interns and theca externa layers. The uterine tissues were separated into myometrium and endometrium The extracted mRNA was converted to cDNA by reverse-transcriptase using oligo-$d(T)_{15}$ primer. Then, the cDNA was amplified by Vent polymerase and arginine vasotocin specific primers. The amplification reaction was incubated by 30 cycles successively, $95^{\circ}C$, $55^{\circ}C$ and $72^{\circ}C$ earth for 1 min. Te comparisons of the mRNA levels encoding arginine vasotocin between the tissues were determined by semi-quantification methods. After amplification of the cDNA, the PCR products were detected in hypothalamus, ovarian tissues and uterine tissues. The results of semi-quantification showed that the levels of arginine vasotocin mRNA in ovarian iud uterine tissues were about from 1/50 to 1/1000 when compared to that in the hypothalamus. The very low levels of mRNA encoding arginine vasotocin in ovarian and uterine tissues probably led us to conclude that arginine vasotocin may play a role of local mediate acting autocrine and/or paracrine.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1708-1714
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• 2005

Keratinocyte growth factor (KGF) functions in epithelial growth and differentiation in many tissues and organs. KGF is expressed in the uterine endometrial epithelial cells during the estrous cycle and pregnancy in pigs, and receptors for KGF (KGFR) are expressed by conceptus trophectoderm and endometrial epithelia. KGF has been shown to stimulate the proliferation and differentiation of conceptus trophectoderm. However, the role of KGF on the endometrial epithelial cells has not been determined. Therefore, this study determined the effect of KGF on proliferation and differentiation of endometrial epithelial cells in vitro and in vivo using an immortalized porcine luminal epithelial (pLE) cell line and KGF infusion into the uterine lumen of pigs between Days 9 and 12 of estrous cycle. Results showed that KGF did not stimulate proliferation of uterine endometrial epithelial cells in vitro and in vivo determined by the $^3$H]thymidine incorporation assay and the proliferating cell nuclear antigen staining, respectively. Effects of KGF on expression of several markers for epithelial cell differentiation, including integrin receptor subunits $\alpha$4, $\alpha$5 and $\beta$1, plasmin/trypsin inhibitor, uteroferrin and retinol-binding protein were determined by RT-PCR, Northern and slot blot analyses, and immunohistochemisty, and KGF did not affect epithelial cell differentiation in vitro and in vivo. These results show that KGF does not induce epithelial cell proliferation and differentiation, suggesting that KGF produced by endometrial epithelial cells acts on conceptus trophectoderm in a paracrine manner rather than on endometrial epithelial cells in an autocrine manner.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.2
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• pp.176-179
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• 2003

Insulin-like growth factor-I (IGF-I) is a polypeptide that has the function of regulating the expression of steroid hormones through endocrine, paracrine, and autocrine actions in reproductive organs. Moreover, IGF-I is involved in ovulation, implantation, maintenance of pregnancy, and development of fetuses in animals. Therefore, this study was conducted to investigate the effects of serum IGF-I concentration on progesterone ($P_4$) concentration and pregnancy rates in Korean native cattle (Hanwoo). Blood was collected at estrus (Day 0) and Day 11. Artificial insemination was performed at Day 0. Serum IGF-I and $P_4$ concentrations were measured by radioimmunoassay (RIA). Overall, $P_4$ concentration was higher at Day 11 than Day 0, whereas the pattern of IGF-I concentration was reversed. When animals were divided into two groups depending on the pregnancy status, $P_4$ concentrations of the pregnant group was significantly higher than that of the non-pregnant group at Day 0 (p<0.05) and Day 11 (p<0.05). But, lower IGF-I concentrations were detected in the pregnant group at Day 0 (p<0.05) and Day 11 (p<0.05) compared to the non-pregnant group. In conclusion, these results indicated that serum IGF-I is inversely associated with $P_4$ concentration during early pregnancy in Hanwoo.

• BMB Reports
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• v.53 no.2
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• pp.118-123
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• 2020

Cardiac regeneration with adult stem-cell (ASC) therapy is a promising field to address advanced cardiovascular diseases. In addition, extracellular vesicles (EVs) from ASCs have been implicated in acting as paracrine factors to improve cardiac functions in ASC therapy. In our work, we isolated human cardiac mesenchymal stromal cells (h-CMSCs) by means of three-dimensional organ culture (3D culture) during ex vivo expansion of cardiac tissue, to compare the functional efficacy with human bone-marrow derived mesenchymal stem cells (h-BM-MSCs), one of the actively studied ASCs. We characterized the h-CMSCs as CD90^low, c-kit^negative, CD105^positive phenotype and these cells express NANOG, SOX2, and GATA4. To identify the more effective type of EVs for angiogenesis among the different sources of ASCs, we isolated EVs which were derived from CMSCs with either normoxic or hypoxic condition and BM-MSCs. Our in vitro tube-formation results demonstrated that the angiogenic effects of EVs from hypoxia-treated CMSCs (CMSC-Hpx EVs) were greater than the well-known effects of EVs from BM-MSCs (BM-MSC EVs), and these were even comparable to human vascular endothelial growth factor (hVEGF), a potent angiogenic factor. Therefore, we present here that CD90^lowc-kit^negativeCD105^positive CMSCs under hypoxic conditions secrete functionally superior EVs for in vitro angiogenesis. Our findings will allow more insights on understanding myocardial repair.

• Journal of Life Science
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• v.11 no.1
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• pp.22-26
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• 2001

In estrogen-dependent MCF-7 human breast cancer cells, $E_2$ at 10 nM stimulated cell proliferation to over 200% compared to the untreated control. EGF and TGF${\alpha}$, which are known as the autocrine/paracrine growth factors induced by $E_2$, also directly stimulated the cell growth in almost as the same extent as $E_2$. DFMO which is the specific inhibitor of ODC could inhibit cell growth even at as low as 0.5 mM. In the treatment with 1 mM DFMO for 4 days, the cell growth was inhibited to 38% of the control. HO-TAM at 1 ${\mu}$M could inhibit the proliferation of MCF-7 cells to 19% of the control. Those inhibitory effects were also found in the cells stimulated with $E_2$, EGF, and TGF${\alpha}$. The inhibitory effects were found even in 2 days of treatment. However, $E_2$, EGF, and TGF${\alpha}$ did not give any effect in the protein synthesis. Neither DFMO or HO-TAM gave any effect on the total protein synthesis. But the pattern of protein secretion was noticeably influenced by the growth stimulants or inhibitors. Proteins of 160, 52, 42, 36, and 32 kDa belonged to the major secretory proteins. Especially, 42 and 36 kDa proteins were most significantly influenced by the treatment of $E_2$, EGF, or TGF$\alpha$. DFMO and HO-TAM inhibited the secretion of these major proteins.

• Journal of Life Science
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• v.24 no.5
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• pp.573-587
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• 2014

Angiogenesis, the formation of new capillary blood vessels, is a tightly regulated process. Under normal physiological conditions, angiogenesis only takes place during embryonic development, wound healing, and female menstruation. Dysregulation of angiogenesis is associated with many diseases, such as cancer, rheumatoid arthritis, psoriasis, and proliferative retinopathy. The growth and expansion of adipose tissue require the formation of new blood vessels. Adipose tissue is probably the most highly vascularized tissue in the body, as each adipocyte is surrounded by capillaries, and the angiogenic vessels supply nutrients and oxygen to adipocytes. Accumulating evidence shows that capillary endothelial cells communicate with adipocytes via paracrine signaling pathways, extracellular components, and direct cell-cell interactions. Activated adipocytes produce multiple angiogenic factors, including VEGF, FGF-2, leptin, and HGF, which either alone or cooperatively stimulate the expansion and metabolism of adipose tissue by increasing adipose tissue vasculature. Recently, it was demonstrated that antiangiogenic herbal Ob-X extracts and Korean red ginseng extracts reduce adipose tissue mass and suppress obesity by inhibiting angiogenesis in obese mice. Thus, angiogenesis inhibitors provide a promising therapeutic approach for controlling human obesity and related disorders.

• International Journal of Vascular Biomedical Engineering
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• v.2 no.1
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• pp.17-24
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• 2004

Tumor angiogenesis was simulated using a two-dimensional computational model. The equation that governed angiogenesis comprised a tumor angiogenesis factor (TAF) conservation equation in time and space, which was solved numerically using the Galerkin finite element method. The time derivative in the equation was approximated by a forward Euler scheme. A stochastic process model was used to simulate vessel formation and vessel elongation towards a paracrine site, i.e., tumor-secreted basic fibroblast growth factor (bFGF). In this study, we assumed a two-dimensional model that represented a thin (1.0 mm) slice of the tumor. The growth of the tumor over time was modeled according to the dynamic value of bFGF secreted within the tumor. The data used for the model were based on a previously reported model of a brain tumor in which four distinct stages (namely multicellular spherical, first detectable lesion, diagnosis, and death of the virtual patient) were modeled. In our study, computation was not continued beyond the 'diagnosis' time point to avoid the computational complexity of analyzing numerous vascular branches. The numerical solutions revealed that no bFGF remained within the region in which vessels developed, owing to the uptake of bFGF by endothelial cells. Consequently, a sharp, declining gradient of bFGF existed near the surface of the tumor. The vascular architecture developed numerous branches close to the tumor surface (the brush-border effect). Asymmetrical tumor growth was associated with a greater degree of branching at the tumor surface.

• The Korean Journal of Physiology
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• v.29 no.2
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• pp.259-267
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• 1995

The renin-angiotensin system plays an important role in the regulation of blood pressure and in body fluid homeostasis. There is increasing evidence for generation of endogenous angiotensin II in many organs and for its role in paracrine functions. Studies were designed to investigate whether hemorrhage produces rapid changes in the gene expression of angiotensinogen in peripheral and brain tissues. Wistar rats received saline drinking water for 7 days, were bled at a rate of $3\;ml\;kg^{-1}\;min^{-1}$ for 7 min, and then decapitated 0, 2, 4, 8, or 24 hr after hemorrhage. Hemorrhage produced a produced hypotension with tachycardia at $2{\pm}8\;hr$, but blood pressure and heart rate had not fully recovered to the basal level at 24 hr. Plasma renin concentration was significantly increased at 2, 4, and 8 hr (maximum sixfold increase at 4 hr) and had returned to the basal level at 24 hr. Renal renin content was significantly increased only at 4 hr after hemorrhage. Angiotensinogen mRNA in both the kidney and liver were stimulated at 2 to 8 hrs, but recovered to the basal level at 24 hr. On the other hand, angiotensinogen mRNA levels il the hypothalamus and brainstem were continuously increased from 2 to 24 hrs. The present study demonstrates the presence of angiotensinogen mRNA in both hepatic and extrahepatic tissues, and more importantly, their up-regulation after hemorrhage. These results suggest that the angiotensinogen-generating systems in the liver, kideny and brain are, at least in part, under independent control and play a local physiological role.

• The Korean Journal of Physiology and Pharmacology
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• v.9 no.5
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• pp.305-314
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• 2005

Diabetes mellitus is associated with vascular complications, including an impairment of vascular function and alterations in the reactivity of blood vessels to vasoactive substances in various vasculature. In the present study, the authors have observed endothelin-B ($ET_B$) receptor agonist-induced relaxation in precontracted mesenteric arterial segments from streptozotocin (STZ)-induced diabetic rats, which was not shown from control rats or in other arterial segments from diabetic rats. Accordingly, the goal of this study was to investigate in what way STZ-induced diabetes altered reactivity of the mesenteric arterial bed and to examine the causal relaxation, if any, between this $ET_B$ receptor-mediated relaxation and endothelial paracrine function, especially nitric oxide (NO) production. The relaxation induced by $ET_B$ agonists was not observed in mesenteric arteries without endothelium. The relaxation to $ET_B$ agonists was completely abolished by pretreatment with BQ788, but not by BQ610. $N_{\omega}-nitro-L-arginine$ methyl ester and soluble guanylate cyclase inhibitors, methylene blue or LY83583 significantly attenuated the relaxant responses to $ET_B$ agonists, respectively. When the expression of eNOS and iNOS was evaluated on agarose gel stained with ethidium bromide, the expression of eNOS mRNA in diabetic rats was significantly decreased, but the expression of iNOS was increased compared with control rats. Furthermore, the iNOS-like immunostaining was densely detected in the endothelium and slightly in the arterial smooth muscle of diabetic rats, but not in control rats. These observations suggest that $ET_B$ receptor may not play a role in maintaining mesenteric vascular tone in normal situation. However, the alterations in $ET_B$ receptor sensitivity were found in diabetic rats and lead to the $ET_B$ agonist-induced vasorelaxation, which is closely related to NO production. In the state of increased vascular resistance of diabetic mesenteric vascular bed, enhanced NO production by activation of iNOS could lead to compensatory vasorelaxation to modulate adequate perfusion pressure to splanchnic area.

• Proceedings of the Korean Nutrition Society Conference
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• 2002.05a
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• pp.29-41
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• 2002

While the sequencing of several genomes was underway, several advanced techniques in genetics, molecular biology and protein chemistry emerged. Within the nutritional sciences, while the focus on nutrition education, epidemiology and public health aspects remains essential; it is crucial to incorporate the new advances in gene and protein discovery in nutritional studies. Nutrition is a discipline that has always integrated social, biochemical and physiological sciences from the studies at the molecule level to studies at the population level. For this reason, nutritionists are in a prime position to readily incorporate the current genomics approaches in nutrition research, All the available analytical techniques can and should be used in modern nutritional sciences. These include genetics, genomics, proteomics and metabolomics which also require integration and use of bioinformatics and computational methods for data analysis and management. These applications will be briefly reviewed with a primary focus on what the genomics and genetics approaches offer to nutritionists. We will use one of our research focus areas to illustrate uses of some of these applications in obesity-hypertension research. Our central hypothesis is that adipose tissue is an endocrine organ that plays a major role in obesity and related hypertension. We are primarily studying the renin angiotensin system (RAS). We provide evidence from our own studies and others for the paracrine as well as endocrine role of adipocyte-derived angiotensin II in adipocyte gene expression, adiposity and blood pressure regulation. Both cell culture studies as well as knockout and transgenic mice models are used to test our hypothesis. Genomics and proteomics technologies are currently developed to complement our physiological and molecular studies on the RAS and for a fine analysis of this system and its function in health and disease.