• Journal of Radiation Protection and Research
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• v.30 no.4
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• pp.197-208
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• 2005

Although little information is available on the underlying mechanisms, various genetic factors have been associated with tissue-specific responses to radiation. In the present study, we explored the possibility whether organ specific gene expression is associated with radiosensitivity using samples from brain, lung and spleen. We examined intrinsic expression pattern of 23 genes in the organs by semi-quantitative RT-PCR method using both male and female C57BL/6 mice. Expression of p53 and p21, well known factors for governing sensitivity to radiation or chemotherapeutic agents, was not different among the organ types. Both higher expression of sialyltransferase, delta7-sterol reductase, leptin receptor splice variant form 12.1, and Cu/Zn superoxide dismutase (SOD) and lower expression of alphaB crystalline were specific for spleen tissue. Expression level of glutathione peroxidase and APO-1 cell surface antigen gene in lung tissue was high, while that of Na, K-ATPase alpha-subunit, Cu/ZnSOD, and cyclin G was low. Brain, radioresistant organ, showed higher expressions of Na, K-ATPase-subunit, cyclin G, and nucleolar protein hNop56 and lower expression of delta7-sterol reductase. The result revealed a potential correlation between gene expression patterns and organ sensitivity, and Identified genes which might be responsible for organ sensitivity.

• Animal cells and systems
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• v.2 no.2
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• pp.249-258
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• 1998

Obesity, one of the most common metabolic diseases in industrial countries is characterized by an increase in the number or size of adipocytes. In an effort to create transgenic mouse models for the study of obesity we developed a novel technique in which adipose tissue can be ablated genetically at will, at any specific developmental stage and/or physiological condition, by the treatment of ganciclovir. We made a series of adipocytespecific expression vectors using minimal regulatory regions of brown adipocyte-specific uncoupling protein (UCP-1) gene and adipocyte-specific aP2 gene, and then analyzed their expression characteristics in cultured cell lines. When both constructs pUCP-LacZ and paP2-LacZ were transfected transiently into differentiating 3T3-L1 (pre-while adipocytes) and HIB-1B (pre-brown adipocytes) cell lines in vitro and then monitored by X-gal staining of cells, these regulatory regions were sufficient to show proper differentiation stage-specific expression in adipocvtes. To confirm that adipocytes expressing HSV-TK controlled by these minimal requlatory elements are sufficient to kill themselves with ganciclovir treatment pUCP-TK and paP2-TK expression constructs were transfected stably into HIB-1B and 3T3-L1 cells, respectively, and their ganciclovir sensitivities were tested during in vitro differentiation of cells. As expected more than 80% of cells were dead by the 7th day of treatment with ganciclovir while negative control cells were not affected at all. The data suqqest that the constructed vectors are suitable for obtaining novel obese transqenic models based on a conditional genetic tissue ablation method.

• Journal of Biomedical Engineering Research
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• v.39 no.1
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• pp.22-29
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• 2018

Intervertebral disc(IVD) mainly consists of Annulus fibrosus(AF) and Nucleus pulposus(NP), playing a role of distributing a mechanical load on vertebral body. IVD tissue engineering has been developed the methods to achieve anatomic morphology and restoration of biological function. The goal of present study is to identify the possibilities for creating a substitute of IVD the morphology and biological functions are the same as undamaged complete IVD. To fabricate the AF and NP combine biphasic IVD tissue, AF tissue scaffolds have been printed by 3D bio-printing system with natural biomaterials and NP tissues have been prepared by scaffold-free culture system. We evaluated whether the combined structure of 3D printed AF scaffold and scaffold-free NP tissue construct could support the architecture and cell functions as IVD tissue. 3D printed AF scaffolds were printed with 60 degree angle stripe patterned lamella structure(the inner-diameter is 5mm, outer-diameter is 10 mm and height is 3 mm). In the cytotoxicity test, the 3D printed AF scaffold showed good cell compatibility. The results of histological and immunohistochemical staining also showed the newly synthesized collagens and glycosaminoglycans, which are specific makers of AF tissue. And scaffold-free NP tissue actively synthesized glycosaminoglycans and type 2 collagen, which are the major components of NP tissue. When we combined two engineered tissues to realize the IVD, combined biphasic tissues showed a good integration between the two tissues. In conclusion, this study describes the fabrication of Engineered biphasic IVD tissue by using enable techniques of tissue engineering. This fabricated biphasic tissue would be used as a model system for the study of the native IVD tissue. In the future, it may have the potential to replace the damaged IVD in the future.

• Journal of Community Nutrition
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• v.8 no.2
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• pp.69-75
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• 2006

Adipose tissue has now been recognized as a rich source of metabolically active molecules that include leptin and angiotensinogen (AGT), the precursor of angiotensin II (Ang II). Both of which have been implicated in the pathogenesis of metabolic alteration and hypertension associated with obesity. In this study, we examined the relationship between body mass index (BMI), adipocyte size, leptin, Ang II secretion and mRNA expression in human adipose tissue obtained from female subjects. Leptin and Ang II were analyzed using specific radioimmunoassay kits following a 48hour tissue culture. Leptin and Ang II secretion varied from 1.4 - 72.1ng/g and 0.8 - 57.3pg/g of tissue respectively. These large individual variations limit significant correlation between BMI, leptin and Ang II secretion. Ang II secretion was significantly higher in the obese than the non-obese (p < 0.05) and positively correlated with BMI. However, no difference in leptin secretion between the obese and the non-obese was observed and leptin secretion showed negative correlation with BMI. No difference in leptin and AGT mRNA expression in adipose tissue between the obese and the non-obese was observed. Although several limitations of this study, we found increased Ang II secretion in obese patients compared with non-obese patients, and positive correlation between AGT and BMI. Observed difference in AGT expression between the obese and the non-obese in this study might be of importance in relation with obesity related hypertension. (J Community Nutrition 8(2): 69-75, 2006)

• Molecules and Cells
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• v.39 no.7
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• pp.524-529
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• 2016

Controlling the production of diverse cell/tissue types is essential for the development of multicellular organisms such as animals and plants. The Arabidopsis thaliana root, which contains distinct cells/tissues along longitudinal and radial axes, has served as an elegant model to investigate how genetic programs and environmental signals interact to produce different cell/tissue types. In the root, a series of asymmetric cell divisions (ACDs) give rise to three ground tissue layers at maturity (endodermis, middle cortex, and cortex). Because the middle cortex is formed by a periclinal (parallel to the axis) ACD of the endodermis around 7 to 14 days post-germination, middle cortex formation is used as a parameter to assess maturation of the root ground tissue. Molecular, genetic, and physiological studies have revealed that the control of the timing and extent of middle cortex formation during root maturation relies on the interaction of plant hormones and transcription factors. In particular, abscisic acid and gibberellin act synergistically to regulate the timing and extent of middle cortex formation, unlike their typical antagonism. The SHORT-ROOT, SCARECROW, SCARECROW-LIKE 3, and DELLA transcription factors, all of which belong to the plant-specific GRAS family, play key roles in the regulation of middle cortex formation. Recently, two additional transcription factors, SEUSS and GA- AND ABA-RESPONSIVE ZINC FINGER, have also been characterized during ground tissue maturation. In this review, we provide a detailed account of the regulatory networks that control the timing and extent of middle cortex formation during post-embryonic root development.

• Journal of Life Science
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• v.15 no.1 s.68
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• pp.71-79
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• 2005

The metabolism of lactate dehydrogenase (EC 1.1.1.27, LDH) and $C_4$ isozyme were studied in tissues of Coreoperca herzi and Pseudogobio esocinus acclimated to rapid increase of dissolved oxygen (DO). In C. herzi the LDH activity was changed $35-39\%$ in brain and liver tissues, and within $20\%$ in other tissues. The $B_4$ isozyme was increased and isozyme containing subunit C was decreased in muscle tissue. The $B_4$ isozyme was increased in heart and kidney. In P. esocinus, the LDH activity in liver tissues was largely increased to $150\%$ for 30 minute and $70\%$ in other tissues. The $A_4$ isozyme was increased in muscle and $B_4$ isozyme was increased in other tissues. Especially, the metabolism of liver tissue in P. esocinus was regulated by increasing liver-specific $C_4$ and decreasing $A_4$ isozyme. But the metabolism of eye tissue in C. herzi was regulated by decreasing LDH activity and eye-specific $C_4$ isozyme. The LDH activity and LDH isozyme in P. esocinus were largely increased than C. herzi acclimated to rapid increase of DO. And eye-specific $C_4$ and liver-specific $C_4$ isozymes played role as lactate oxidase. Therefore, the response of species acclimated to rapid increase of DO seems to be variable, perhaps due to prior exposure to environmental conditions.

• KSBB Journal
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• v.18 no.4
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• pp.329-334
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• 2003

The present study was aimed at investigating the regulatory mechanism in tissue-specific expression of insulin-like growth factor-I (IGF-I) gene. The expression of IGF-I gene was determined by a solution hybridization/RNase protection assay using total RNA prepared from rat liver or brain of various ages. The levels of IGF-I transcripts were increased in liver gradually after birth, but decreased in brain. By using an oligonucleotide (FRE) corresponding to the C/EBP binding site of the rat IGF-I exon 1, multiple forms of C/EBP${\alpha}$ and C/EBP${\beta}$ proteins, which have DNA-binding activity, were detected in the rat liver or brain. Western immunoblot and southwestern analyses show that p42$\^$C/EBP${\alpha}$/, p38$\^$C/EBP${\alpha}$/, p35$\^$C/EBP${\alpha}$/, p38$\^$C/EBP${\beta}$/, and p35$\^$C/EBP${\beta}$ form specific complexes with the IGF-I exon 1 oligonucleotide in liver nuclear extract and that p42$\^$C/EBP${\alpha}$/ and p38$\^$C/EBP${\beta}$/ form complexes in brain. These data suggest that the formation of FRE-C/EBP isoform complexes may play important roles in the tissue-specific regulation of IGF-I gene expression.

• Fisheries and Aquatic Sciences
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• v.11 no.2
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• pp.88-97
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• 2008

Lipoproteins are complexes of lipids and specific apolipoproteins that are involved in lipid transport and redistribution among various tissues. In this study, we isolated full-length apolipoprotein cDNA sequences encoding apolipoprotein A-I (apoA-I), apoE, apoC-II, and apo-14 kDa in barred knifejaw, Oplegnathus fasciatus. In addition, we reconstructed phylogenetic trees and investigated mRNA tissue distributions. Alignment analyses of amino acid sequences revealed that secondary structures of the polypeptides apoA-I, apoE, and apoC-II in barred knifejaw are well conserved with their teleostean and mammalian counterparts in terms of characteristic tandem repetitive units forming amphipathic ${\alpha}$-helices. Both the sequence alignment data and cleavage sites of apo-14 kDa indicated a clear differentiation between Percomorpha and Cypriniformes. Meanwhile, the phylogenetic trees of apolipoprotein sub-families suggested that the common ancestor prior to the split of the Actinopterygii (ray-finned fishes) and Sarcopterygii (tetrapods) would have possessed the primordial protein-encoding genes. Tissue distribution of each apolipoprotein transcript determined by semi-quantitative RTPCR showed that barred knifejaw apoA-I transcripts were more or less ubiquitously expressed in the liver, intestines, brain, muscle, spleen, and kidney. The most striking difference from previous observations on barred knifejaw was the ubiquitous expression of apoE across all somatic tissues. Barred knifejaw apoC-II showed tissue-specific expression in the liver and intestines, while the liver and brain were the major sites of apo-14kDa mRNA synthesis.

• Biomedical Science Letters
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• v.11 no.1
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• pp.1-8
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• 2005

Fibrates are a class of hypolipidemic agents whose effects are mediated by activation of a specific transcription factor called the peroxisome proliferator-activated receptor $\alpha\;(PPAR\alpha).\;PPAR\alpha$ regulates the pathways of lipid catabolism such as fatty acid oxidation and the triglyceride metabolism, resulting in the treatment of hyperlipidemia. The decreased levels of plasma triglycerides by fibrates are responsible for hypertrophy and hyperpalsia of adipose cells. To determine whether fenofibrate regulates adipogenesis in female C57BL/6J mice, we measured the effects of fenofibrate on not only body weight, adipose tissue mass and serum triglycerides, but also the histology of adipose tissue and the expression of adipocyte marker genes. Fenofibrate did not inhibit high fat diet-induced increases in body weight, adipose tissue mass and serum triglycerides. Furthermore, fenofibrate did not cause the changes in the size and number of adipocytes and the expression of adipocyte-specific genes such as leptin and $TNF\alpha$. Therefore, this study demonstrates that fenofibrate does not affect adipogenesis in female mice.

• IMMUNE NETWORK
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• v.15 no.3
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• pp.111-120
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• 2015

Dendritic cells (DCs) play a significant role in establishing self-tolerance through their ability to present self-antigens to developing T cells in the thymus. DCs are predominantly localized in the medullary region of thymus and present a broad range of self-antigens, which include tissue-restricted antigens expressed and transferred from medullary thymic epithelial cells, circulating antigens directly captured by thymic DCs through coticomedullary junction blood vessels, and peripheral tissue antigens captured and transported by peripheral tissue DCs homing to the thymus. When antigen-presenting DCs make a high affinity interaction with antigen-specific thymocytes, this interaction drives the interacting thymocytes to death, a process often referred to as negative selection, which fundamentally blocks the self-reactive thymocytes from differentiating into mature T cells. Alternatively, the interacting thymocytes differentiate into the regulatory T (Treg) cells, a distinct T cell subset with potent immune suppressive activities. The specific mechanisms by which thymic DCs differentiate Treg cells have been proposed by several laboratories. Here, we review the literatures that elucidate the contribution of thymic DCs to negative selection and Treg cell differentiation, and discusses its potential mechanisms and future directions.