• Journal of Veterinary Science
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• v.22 no.1
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• pp.6.1-6.6
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• 2021

Stem cell-based products (SCPs) are an emerging field of veterinary medicine that focuses on the regeneration, repair, or replacement of damaged tissues or organs. However, there are some issues in applying the traditional regulatory guideline for the approval of SCPs as veterinary medicinal products. This article describes the positions of Korea, US, and EU regarding SCPs, and compares the regulatory guidelines of each country for their safety evaluation. Although there are some differences in the regulatory guidelines, similar considerations in identifying the quality of SCPs and their safety has adopted. Overall, these guidelines need to be harmonized among countries.

• International Journal of Stem Cells
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• v.16 no.1
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• pp.16-26
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• 2023

Despite long-term research achievements, the development of cell therapy (CT) products remains challenging. This is because the risks experienced by the subject and therapeutic effects in the clinical trial stage are unclear due to the various uncertainties of CT when administered to humans. Nevertheless, as autologous cell products for systemic administration have recently been approved for marketing, CT product development is accelerating, particularly in the field of unmet medical needs. The human experience of CT remains insufficient compared with other classes of pharmaceuticals, while there are countless products for clinical development. Therefore, for many sponsors, understanding the rationale of human application of an investigational product based on the consensus and improving the ability to apply it appropriately for CT are necessary. Thus, defining the level of evidence for safety and efficacy fundamentally required for initiating the clinical development and preparing it using a reliable method for CT. Furthermore, the expertise should be strengthened in the design of the first-in-human trial, such as the starting dose and dose-escalation plan, based on a sufficiently acceptable rationale. Cultivating development professionals with these skills will increase the opportunity for more candidates to enter the clinical development phase.

• Toxicological Research
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• v.35 no.4
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• pp.343-351
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• 2019

Many in vitro developmental toxicity assays have been proposed over several decades. Since the late 1980s, we have made intermittent attempts to introduce in vitro assays as screening tests for developmental toxicity of inhouse candidate products. Two cell-based assays which were developed two decades apart were intensively studied. One was an assay of inhibitory effects on mouse ascites tumor cell attachment to a concanavalin A-coated plastic sheet surface (MOT assay), which we studied in the early days of assay development. The other was an assay of inhibitory effects on the differentiation of mouse embryonic stem cell to beating heart cells (EST assay), which we assessed more recently. We evaluated the suitability of the assays for screening in-house candidates. The concordance rates with in vivo developmental toxicity were at the 60% level. The EST assay classified chemicals that inhibited cell proliferation as embryo-toxic. Both assays had a significant false positive rate. The assays were generally considered unsuitable for screening the developmental toxicity of our candidate compounds. Recent test systems adopt advanced technologies. Despite such evolution of materials and methods, the concordance rates of the EST and MOT systems were similar. This may suggest that the fundamental predictivity of in vitro developmental toxicity assays has remained basically unchanged for decades. To improve their predictivity, in vitro developmental toxicity assays should be strictly based on elucidated pathogenetic mechanisms of developmental toxicity.

• Food Science of Animal Resources
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• v.44 no.5
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• pp.1108-1125
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• 2024

Cultured meat is under investigation as an environmentally sustainable substitute for conventional animal-derived meat. Employing a scaffolding technique is one approach to developing cultured meat products. The objective of this research was to compare soy and pea protein in the production of hydrogel scaffolds intended for cultured meat. We examined the gelation process, physical characteristics, and the ability of scaffolds to facilitate cell adhesion using mesenchymal stem cells derived from porcine adipose tissue (ADSCs). The combination of soy and pea proteins with agarose and agar powders was found to generate solid hydrogels with a porous structure. Soy protein-based scaffolds exhibited a higher water absorption rate, whereas scaffolds containing agarose had a higher compressive strength. Based on Fourier transform infrared spectroscopy analysis, the number of hydrophobic interactions increased between proteins and polysaccharides in the scaffolds containing pea proteins. All scaffolds were nontoxic toward ADSCs, and soy protein-based scaffolds displayed higher cell adhesion and proliferation properties. Overall, the soy protein-agarose scaffold was found to be optimal for cultured meat production.

• Korean Journal of Pharmacognosy
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• v.37 no.1 s.144
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• pp.16-20
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• 2006

The protective effects of the aqueous MeOH extracts of stem and root Acanthopanax koreanum Nakai against oxidative stress were investigated. Anti-oxidant activity of the stem extract of A. koreanum was observed in the DPPH free radical scavenging $(IC_{50}=58.7\;{\mu}g/ml)$ and the SOD test $(IC_{50}=17.52\;{\mu}g/ml)$. According to data analysis of cell survival ratio of normal fibroblasts, the skin irritation by both extracts from A. koreanum was concerned. However, in the skin primary parch test, both extracts obtained Grade I, which means that there was no skin irritation. After induction of oxidative irritation, cell survival ratio of normal fibroblasts was also monitored and it turned out that stress-inducing group with both extracts had more increased cell survival ratio. The cell extension of the stress-inducing group treated with the stem extract was most dominant in morphological study. Based on these results, the stem extract of A. koreanum showed the protective effect against oxidative stress on normal fibroblast.

• Journal of mucopolysaccharidosis and rare diseases
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• v.3 no.1
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• pp.14-19
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• 2017

Lysosomal storage diseases (LSDs) are a group of rare inherited metabolic disorders caused by the deficiency of specific lysosomal enzymes and subsequent accumulation of substrates. Enzyme deficiency leads to progressive intra-lysosomal accumulation of the incompletely degraded substances, which cause dysfunction and destruction of the cell and eventually multiple organ damage. Patients have a broad spectrum of clinical phenotypes which are generally not specific for some LSDs, leading to missed or delayed diagnosis. Due to the availability of treatment including enzyme replacement therapy (ERT) and hematopoietic stem cell transplantation for some LSDs, early diagnosis is important. ERT products have been approved with optimal outcomes for some LSDs in the recent decades, including Gaucher, Fabry, mucopolysaccharidosis (MPS) I, Pompe, MPS VI, MPS II, and MPS IVA diseases. ERT can stabilize the clinical condition, prevent disease progression, and improve the long-term outcome of these diseases, especially if started prior to irreversible organ damage. Based on the availability of therapy and suitable screening methods in the recent years, some LSDs, including Pompe, Fabry, Gaucher, MPS I, MPS II, and MPS VI diseases have been incorporated into nationwide newborn screening panels in Taiwan.

• Journal of Microbiology and Biotechnology
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• v.30 no.11
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• pp.1769-1776
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• 2020

As part of our current work to discover structurally and/or biologically novel compounds from Korean wild mushrooms, we isolated five ergostane-type steroids (1-5) from the fruiting bodies of Xerula furfuracea via repeated column chromatographic separations and HPLC purification. The chemical structures of the isolated steroids were shown to be (22E,24R)-24-methylcholesta-4,22-diene-3,6-dione (1), ergosta-7,22-diene-3β,5α,6β-triol (2), ergosta-7,22-diene-3β,5α,6β,9α-tetraol (3), (22E,24R)-5α,8α-epidioxyergosta-6,22-diene-3β-ol-3-O-β-D-glucopyranoside (4), and (22E,24R)-5α,8α-epidioxyergosta-6,9,22-triene-3β-ol-3-O-β-D-glucopyranoside (5)based on comparison of the data regarding their spectroscopic and physical properties with those of previous studies. Notably, this is the first report on the presence of the identified steroids (1-5) in this mushroom. We tested compounds 1-5 to determine their effects on adipogenesis and osteogenesis in the mouse mesenchymal stem cell line C3H10T1/2 and found that compounds 4 and 5 suppressed the differentiation of stem cells into adipocytes. Notably, in addition to its suppressive effect on adipogenesis, compound 5 was also shown to promote the osteogenic differentiation of stem cells. These findings demonstrate that the bioactive compounds isolated might be effective for the treatment of menopause-associated syndromes, such as osteoporosis and obesity, as the isolated compounds were shown to suppress adipogenesis and/or promote osteogenesis of stem cells.

• Journal of Applied Biological Chemistry
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• v.51 no.3
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• pp.83-87
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• 2008

Tension wood, a specialized tissue developed in the upper side of the leaning stem and drooping branches of angiosperm, is an attractive experimental system attractive for exploring the development and the biochemical pathways of the secondary cell wall formation, as well as the control mechanism of the carbon flux into lignin, cellulose, and hemicellulose. However, the mechanism underlying the induction and the development of the tension wood is largely unknown. Recently, several researchers suggested the possible roles of the plant growth hormones including auxin, gibberellin, and ethylene mainly based on the expression pattern of the genes in this specialized tissue. In addition, expressed sequence tag of Poplar and Eucalyptus provide global view of the genetic control underlying the tension wood formation. However, the roles of the majority of the identified genes have not yet been clearly elucidated. The present review summarized current knowledge on the biosynthesis of tension wood to provide a brief synopsis of the molecular mechanism underlying the development of the tension wood.

• Journal of Life Science
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• v.29 no.12
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• pp.1386-1392
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• 2019

This study investigated the potential of dye plants as natural oral health products. The antibacterial activity of ethanol stem extracts of A. japonica, R. verniciflua Stokes, G. jasminoides, D. morbifera, P. amurense Rupr., and S. japonica against P. gingivalis KCTC 5352, S. mutans KCTC3065, S. downei KCTC3634, S. sanguinis KCTC3284, and S. gordonii KCTC 3286 was confirmed. Among the stem extracts from 6 dye plants grown in Korea, ethanol extract from A. japonica stem (1 mg/disc) showed the highest antibacterial activity against P. gingivalis KCTC5352. The A. japonica stem extracts showed antibacterial activity similar to chlorhexidine, which was used as a positive control. The MIC and MBC of P. gingivalis KCTC5352 were 0.4 mg/ml and 0.6 mg/ml, respectively. The biofilm production rate and cell growth of P. gingivalis KCTC5352 in the cultures treated with 0.2-2.0 mg/ml of A. japonica extract were significantly decreased in a concentration-dependent manner. In addition, the mRNA expression of the superoxide dismutase and fimA associated with fimbriae formation in these cultures was suppressed, also in a concentration-dependent manner. Based on these results, it is concluded that A. japonica stem extracts can be used as an oral health product derived from natural materials, as demonstrated by its antibacterial action against and inhibition of biofilm formation of P. gingivalis KCTC5352.

• Journal of the Korean Wood Science and Technology
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• v.48 no.4
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• pp.513-526
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• 2020

The existing preservation methods are difficult to be applied to a large dimension log which is needed for making traditional wooden ship 'Jalur' in Riau Province. Novel techniques to provide the use of readily available species to replace traditional species alternative were investigated. These included infusion and a combination of injection and bandage-wrapping methods for preserving living trees of Balam (Macaranga conifera (Rchb.f. & Zoll.) Müll.Arg.) and Bintangor (Calophyllum soulattri Burm.f.). Water-based boron compounds were applied as wood preservatives. In total, 18 discs from the bottom, middle, and top of four trees and two controls were used. Trees undergoing treatment were also used to see how wood anatomical structure might affect the boron penetration. The overall aim was to identify the best method for use in Jalur manufacturing. The results showed that in infused Balam tree where the hose position for the preservative intake was deep (10-15 cm from the bark), no boron compound was observed in the outer sapwood. Combination of injection and bandage-wrapping method gave higher percentage of boron penetration at bottom and middle of Balam tree. However, infused Bintangor showed 100% boron penetration. The larger vessel diameter, the absence of tyloses, and the simple perforation plates in Bintangor wood were likely to have contributed to the higher penetration of boron. The combination of bandage-wrapping and infusion, or alternatively by infusing the living trees close to the bark, and at as low as position in the stem gives better protection when treatments are applied to living trees.