• Journal of Life Science
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• v.31 no.4
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• pp.389-399
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• 2021

This study determined the effects of Centella asiatica leaf on H₂O₂ induced cell cycle arrest, mitochondrial activity, and proinflammatory cytokine production in human dermal fibroblast (HDF) cells. We used an 80% methanol extract of C. asiatica, its ethyl acetate fraction, and asiaticoside, the major constituent of C. asiatica. The C. asiatica extract, its ethyl acetate fraction, and asiaticoside attenuated G1 cell cycle-arrest and the apoptotic effect caused by H₂O₂-induced oxidative stress. The cells treated with C. asiatica extract, its ethyl acetate fraction, and asiaticoside secreted lower levels of TNF-α and IL-6. The antioxidant effect of asiaticoside was higher than that of C. asiatica extract and its ethyl acetate fraction. Treatment with C. asiatica extract, its ethyl acetate fraction, and asiaticoside also increased the mitochondrial membrane potential and restored normal mitochondrial morphology. Following H₂O₂ stress induction, cells treated with C. asiatica extract, its ethyl acetate fraction, and asiaticoside showed increased mitochondrial oxygen consumption rates and decreases in the TLR4-MyD88-TRAF6-p65 pathway activity. These findings suggest that C. asiatica extract, its ethyl acetate fraction, and asiaticoside have antioxidant and anti-inflammatory effects, as well as the ability to control the mitochondrial activities of HDF cells.

• Journal of Life Science
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• v.31 no.12
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• pp.1142-1148
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• 2021

As the average human lifespan has been extended, there has been a lot of interest in the quality of life of women after menopause. It is known that the average age of menopause among Korean women is 49.7 years, and the post-menopausal life of a woman takes up more than one third of her life. L-ascorbic acid (AsA) is known to be involved in the synthesis and maturation of collagen, a bone constituent protein. The aim of this review is to discuss the potential of AsA in bone health in postmenopausal women. AsA plays an important role in collagen biosynthesis, and collagen is a protein constituting bone and is a necessary material for calcification of the bone matrix. Collagen crosslinking is necessary for the stabilization and elasticity of collagen fibers during growth and matruation of animals, but an excessive increase is likely to lead to further aging because the movement of intercellular nutrients or waste is suppressed. AsA acts as a reducing agent to stabilize the immature collagen crosslinking and suppress pyridinoline production, a mature crosslinking. Therefore, AsA participates in collagen biosynthesis and helps bone tissue health, while regulating the excessive maturation of collagen crosslinking, it is expected to play an important role in bone-related problems that may occur in postmenopausal women.

• Journal of Life Science
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• v.32 no.11
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• pp.882-889
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• 2022

Breast cancer anti-estrogen resistance 3 (BCAR3) has been identified as one of the genes that induces anti-estrogen resistance in breast cancer. We have previously reported that BCAR3 activates promoters of c-Jun, activator protein-1, and the serum response element. In this study, we investigated the functional role of BCAR3 in the activation of the estrogen response element (ERE) in normal human breast MCF-12A cells. Transient expression of BCAR3 induced ERE activation, which was further increased by 17β-estradiol treatment but was not blocked by the anti-estrogen tamoxifen. Next, we studied the signaling pathway of BCAR3 leading to ERE activation. BCAR3-mediated ERE activation was inhibited by LY294002 and AZD5363, inhibitors of the phosphatidylinositol (PI) 3-kinase pathway, but not by PD98059 and U0126, inhibitors of the mitogen-activated protein kinase pathway. ERE activation was induced by the catalytic subunit p110α. of PI3-kinase or the active mutant of Akt, and this activation was not further increased by additional BCAR3 transfection. Based on these results, we propose that BCAR3 plays an important role in ERE activation through the PI3-kinase/Akt pathway in human breast MCF-12A cells.

• Journal of Life Science
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• v.32 no.6
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• pp.476-481
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• 2022

Ubiquitin signaling regulates virtually all aspects of eukaryotic biology and dynamic processes in which protein substrates are modified by ubiquitin. To regulate these processes, deubiquitinating enzymes (DUBs) cleave ubiquitin or ubiquitin-like proteins from these substrates. DUBs have been implicated in the pathogenesis of cancer, leading to the development of increasing numbers of small-molecule DUB inhibitors. On the other hand, recent studies have focused on the function of DUBs in metabolic diseases such as obesity, diabetes, and fatty liver diseases. DUBs play a positive or negative role in the progression and development of metabolic diseases. Their involvement in cell pathology and regulation of major transcription factors in metabolic syndrome has been examined in vitro and in animal and human biopsies. UCH, USP7, and USP19 were linked to adipocyte differentiation, body weight gain, and insulin resistance in genetic or diet-induced obesity. CYLD, USP4, and USP18 were found to be closely associated with fatty liver diseases. In addition, these liver diseases were accompanied by body weight change in certain cases. Collectively, in this review, we discuss the current understanding of DUBs in metabolic diseases with a particular focus on obesity. We also provide basic knowledge and regulatory mechanisms of DUBs and suggest these enzymes as therapeutic targets for metabolic diseases.

• Journal of Life Science
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• v.32 no.2
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• pp.142-147
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• 2022

Oxysterols are known to be involved in the physiopathology of atherosclerosis. Since 7-ketocholesterol (7-KC) is found in large amounts in oxysterols and in atherosclerotic plaque, the study on how 7-KC may affect monocyte differentiation induced by phorbol myristate acetate (PMA) in the monocytic cell line, THP-1, is essential. 7-KC induced a dose-dependent reduction in cell proliferation without inducing cytotoxicity, and the substantial staining of Nile red demonstrates the increased absorption of intracellular lipids. Although 7-KC itself did not increase cell adhesion, it markedly decreased the adhesion of cells treated with PMA. Furthermore, by observing the effect of 7-KC on phagocytosis using fluorescent-labeled latex beads, 7-KC's ability to abolish phagocytosis in PMA-stimulated macrophages was illustrated. The effect of 7-KC on the expression of selected protein markers on the process of differentiation induced by PMA in THP-1 cells was also examined. 7-KC inhibited expression of ICAM-1, CD11a, SR-A1, and SR-B2 (CD36) in PMA-stimulated THP-1 cells. Conversely, 7-KC drastically increased the expression of SR-D1 (CD68)in PMA-stimulated THP-1 cells. In conclusion, these results suggest that 7-KC modulates monocyte differentiation and activation via the intracellular accumulation of lipid droplets.

• Journal of Life Science
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• v.33 no.3
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• pp.227-233
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• 2023

The purpose of this paper was to describe a statistical analysis for the spatial distribution of geographical distances of Erythronium japonicum at Mt. Geumjeong in Korea. The spatial pattern of E. japonicum was analyzed according to the nearest neighbor rule, population aggregation under different plot sizes by dispersion indices, and spatial autocorrelation. Most natural plots of E. japonicum were uniformly distributed in the forest community. Disturbed plots were aggregately distributed within 5 m × 5 m of one another. Neighboring patches of E. japonicum were predominantly 7.5~10 m apart on average. If the natural populations of E. japonicum were disturbed by human activities, then the aggregation occurred in a shorter distance than the 7.5~10 m distance scale. The Morisita index (IM) is related to the patchiness index (PAI) that showed the 2.5 m × 5 m plot had an overly steep slope at the west and south areas when the area was smaller than 5 m × 5 m. When the patch size was one 2.5 m × 5 m quadrat at the west distributed area of Mt. Geumjeong, the cluster was determined by both species characteristics and environmental factors. The comparison of Moran's I values to a logistic regression indicated that individuals in E. japonicum populations at Mt. Geumjeong could be explained by isolation by distance.

• Journal of Marine Life Science
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• v.8 no.1
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• pp.68-77
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• 2023

In this study, we investigated the quantitative distribution of microplastics in the surface seawater at 8 points near the Taean Peninsula using fluorescence staining. The study revealed a detection range of microplastics from 0 to 360.5 particles/l, with an average of 149.7 ± 46.0 particles/l. When classifying the microplastics by size, it was found that particles smaller than 50 ㎛ were dominant, although there were differences at Site 3. Moreover, it was not possible to identify clear correlations when comparing the number of microplastics based on collection area and particle size. Various physical and chemical factors, including plastic material, dynamic ocean conditions (such as currents, wind, waves, tides), geological characteristics (topography, slope), sediment materials including coastal organisms, human activities (fishing, development, tourism), and weather conditions (floods, rainfall), affect the behavior of microplastics. Therefore, future efforts should focus on standardizing quantitative analysis methods and conducting fundamental research on microplastic monitoring, including the analysis of environmental factors.

• Journal of Life Science
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• v.33 no.9
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• pp.703-712
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• 2023

Angiogenesis, the formation of blood vessels from pre-existing vessels, is a multistep process regulated by modulators of angiogenesis. It is essential for various physiological processes, such as embryonic development, chronic inflammation, and wound repair. Dysregulation of angiogenesis causes many diseases, such as cancer, autoimmune diseases, rheumatoid arthritis, cardiovascular disease, and delayed wound healing. However, the number of effective anti-angiogenic drugs is limited. Recent research has focused on identifying potential drug candidates from natural sources. For example, marine natural products have been shown to have anti-cancer, anti-oxidant, anti-inflammatory, antiviral, and wound-healing effects. Thus, this study aimed to describe the angiogenesis inhibitory effect of Hizikia fusiforms (brown algae) extract. The hexane extract of H. fusiformis has shown inhibitory effects on in vitro angiogenesis assays, such as cell migration, invasion, and tube formation in human umbilical vein endothelial cells (HUVECs). The hexane extract of H. fusiformis (HFH) inhibited in vivo angiogenesis in a mouse Matrigel gel plug assay. In addition, the protein expression of vascular endothelial growth factor (VEGF), mitogen-activated protein kinase (MAPK)/extracellular signal kinase, and AKT serine/threonine kinase 1 decreased following treatment with H. fusiformis extracts. Our results demonstrated that the hexane extract of H. fusiformis (HFH) inhibits angiogenesis in vitro and in vivo.

• Journal of Life Science
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• v.32 no.3
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• pp.196-201
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• 2022

Insects have been proposed as new protein sources for human nutrition, and protein availability is affected by insect characteristics. Fermentation can be used to obtain a variety of insect-based ingredients and products with unique properties, but its effect on protein availability is unknown. Fermented cricket (Gryllus bimaculatus) powder consists mainly of protein, and its oral administration has been reported to improve hair growth in androgenetic alopecia. The purpose of this study was to evaluate the hair-promoting activity of fermented cricket powder in an animal model using male C57BL/6 mice (25-30 g). The abdominal hair of the mouse (2x2.5 cm) was gently removed, and the groups fed as follows: Intact controls (no cricket powder); cricket powder only; and fermented cricket powder only. Food was applied daily for 11 weeks. Observational and physical examinations were performed and the results of the different groups compared. The application of fermented cricket powder significantly (p<0.01) promoted hair growth compared to the intact controls. The C57BL/6 results confirmed increased growth after seven weeks when the proportion of anagen follicles had increased by about 125% and 120% in the control and cricket powder groups, respectively. In conclusion, fermented cricket powder can be seen as a promising alternative alopecia treatment because it promotes hair growth, and, given the powder's composition, trace elements such as amino acids may have contributed to these effects.

• Journal of Life Science
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• v.33 no.6
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• pp.523-529
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• 2023

Ubiquitination is a post-translational modification that is involved in the quality control of proteins and responsible for modulating a variety of cellular physiological processes. Protein ubiquitination and deubiquitination are reversible processes that regulate the stability of target substrates. The ubiquitin proteasome system (UPS) helps regulate tumor-promoting processes, such as DNA repair, cell cycle, apoptosis, metastasis, and angiogenesis. The UPS comprises a combination of ubiquitin, ubiquitin-activating enzymes (E1), ubiquitin-conjugating enzymes (E2), and ubiquitin-ligase enzymes (E3), which complete the degradation of target proteins. Ubiquitin-conjugating enzymes (UBE2s) play an inter-mediate role in the UPS process by moving activated ubiquitin to target proteins through E3 ligases. UBE2s consist of 40 members and are classified according to conserved catalytic ubiquitin-conjugating (UBC) domain-flanking extensions in humans. Since UBE2s have specificity to substrates like E3 ligase, the significance of UBE2 has been accentuated in tumorigenesis. The dysregulation of multiple E2 enzymes and their critical roles in modulating oncogenic signaling pathways have been reported in several types of cancer. The elevation of UBE2 expression is correlated with a worse prognosis in cancer patients. In this review, we summarize the basic functions and regulatory mechanisms of UBE2s and suggest the possibility of their use as therapeutic targets for cancer.