• Experimental and Molecular Medicine
• /
• v.50 no.11
• /
• pp.5.1-5.14
• /
• 2018

Oxidative stress-induced mitochondrial dysfunction is implicated in the pathogenesis of intervertebral disc degeneration (IVDD). Sirtuin 3 (SIRT3), a sirtuin family protein located in mitochondria, is essential for mitochondrial homeostasis; however, the role of SIRT3 in the process of IVDD has remained elusive. Here, we explored the expression of SIRT3 in IVDD in vivo and in vitro; we also explored the role of SIRT3 in senescence, apoptosis, and mitochondrial homeostasis under oxidative stress. We subsequently activated SIRT3 using honokiol to evaluate its therapeutic potential for IVDD. We assessed SIRT3 expression in degenerative nucleus pulposus (NP) tissues and oxidative stress-induced nucleus pulposus cells (NPCs). SIRT3 was knocked down by lentivirus and activated by honokiol to determine its role in oxidative stress-induced NPCs. The mechanism by which honokiol affected SIRT3 regulation was investigated in vitro, and the therapeutic potential of honokiol was assessed in vitro and in vivo. We found that the expression of SIRT3 decreased with IVDD, and SIRT3 knockdown reduced the tolerance of NPCs to oxidative stress. Honokiol ($10{\mu}M$) improved the viability of NPCs under oxidative stress and promoted their properties of anti-oxidation, mitochondrial dynamics and mitophagy in a SIRT3-dependent manner. Furthermore, honokiol activated SIRT3 through the AMPK-PGC-$1{\alpha}$ signaling pathway. Moreover, honokiol treatment ameliorated IVDD in rats. Our study indicated that SIRT3 is involved in IVDD and showed the potential of the SIRT3 agonist honokiol for the treatment of IVDD.

• Journal of the Korean Electrochemical Society
• /
• v.22 no.4
• /
• pp.139-147
• /
• 2019

Lithium-ion battery (LiB) with high energy density and efficiency has been utilized for the electric vehicle (EV) and energy storage system (ESS) as well as portable devices. However, as explosion accidents have frequently happened till lately, all-solid-state lithium secondary battery (ALSB) began to get in a spotlight because it can secure a very high safety and energy density by substituting flammable organic liquid electrolyte to nonflammable inorganic solid electrolyte. In spite of ALSB's certain merits, it has shown much poorer performance of cells than one of LiB due to some challenges, which have been small or never dealt with in the LiB system. Hence, although plenty of studies made progress to solve them, an approach about design of all-solid-state electrode (ASSE) has been limited on account of difficulty of ALSB's experiments. That is why the virtual 3D structure of an all-solid-state electrode has to be built and used for the prediction of cell performance. In this study, we elucidate how to form the 3D ASSE structure and what to be needed for the simulation of characteristics on ALSB. Furthermore, the ultimate orientation of 3D modeling and simulation for the study of ALSB are briefly suggested.

• Korean Chemical Engineering Research
• /
• v.57 no.4
• /
• pp.512-518
• /
• 2019

To develop a membrane electrode assembly (MEA) with lower Pt loading and higher performance in proton exchange membrane fuel cells (PEMFCs), it is an important research issue to understand interfacial structure of Pt/C catalyst and ionomer and design the catalyst layer structure. In this study, we prepared short-side-chain Nafion-based ionomer dispersion using propylene glycol (PG) as a solvent instead of water which is commonly used as a solvent for commercially available ionomers. Cathode catalyst layers with different ionomer content from 20 to 35 wt% were prepared using the ionomer dispersion for the fabrication of four different MEAs, and their fuel cell performance was evaluated. As the ionomer content increased to 35 wt%, the performance of the prepared MEAs increased proportionally, unlike the commercially available water-based ionomer, which exhibited an optimum at about 25 wt%. Small size micelles and slow evaporation of PG in the ionomer dispersion were effective in proton transfer by inducing the formation of a uniformly structured catalyst layer, but the low oxygen permeability problem of the PG-based ionomer film should be resolved to improve the MEA performance.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.42 no.1
• /
• pp.151-157
• /
• 2019

This study is about the process capability index (PCI). In this study, we introduce several indices including the index $C_{PR}$ and present the characteristics of the $C_{PR}$ as well as its validity. The difference between the other indices and the $C_{PR}$ is the way we use to estimate the standard deviation. Calculating the index, most indices use sample standard deviation while the index $C_{PR}$ uses range R. The sample standard deviation is generally a better estimator than the range R. But in the case of the panel process, the $C_{PR}$ has more consistency than the other indices at the point of non-conforming ratio which is an important term in quality control. The reason why the $C_{PR}$ using the range has better consistency is explained by introducing the concept of 'flatness ratio'. At least one million cells are present in one panel, so we can't inspect all of them. In estimating the PCI, it is necessary to consider the inspection cost together with the consistency. Even though we want smaller sample size at the point of inspection cost, the small sample size makes the PCI unreliable. There is 'trade off' between the inspection cost and the accuracy of the PCI. Therefore, we should obtain as large a sample size as possible under the allowed inspection cost. In order for $C_{PR}$ to be used throughout the industry, it is necessary to analyze the characteristics of the $C_{PR}$. Because the $C_{PR}$ is a kind of index including subgroup concept, the analysis should be done at the point of sample size of the subgroup. We present numerical analysis results of $C_{PR}$ by the data from the random number generating method. In this study, we also show the difference between the $C_{PR}$ using the range and the $C_P$ which is a representative index using the sample standard deviation. Regression analysis was used for the numerical analysis of the sample data. In addition, residual analysis and equal variance analysis was also conducted.

• Korean Journal of Plant Resources
• /
• v.34 no.2
• /
• pp.186-196
• /
• 2021

In this study, we investigated inhibitory effect of red sweet pepper (Capsicum annuum L.) on triglyceride biosynthesis in Rhodosporidium toruloides. There was no significant difference in the total lipid content of all the experimental groups including 0.02, 0.1 and 0.5% (w/v) of red sweet pepper 70% ethanol extract treatment (RSPE). However, the triglyceride content was significantly decreased in RSPE group campared to the control group. When the formation of lipid droplet in the oleaginous yeast was examined, a small amount of fluorescence was observed compared to the control as the concentration of RSPE increased. The number of cells and free fatty acid increased in a concentration-dependent manner. These results suggest that RSPE has an anti-obesity effect.

• Journal of Ginseng Research
• /
• v.45 no.2
• /
• pp.325-333
• /
• 2021

Background: Alzheimer's disease (AD) is one of the most prevalent neurodegenerative disorders. Enhancing hippocampal neurogenesis by promoting proliferation and differentiation of neural stem cells (NSCs) is a promising therapeutic strategy for AD. 20(S)-protopanaxadiol (PPD) and oleanolic acid (OA) are small, bioactive compounds found in ginseng that can promote NSC proliferation and neural differentiation in vitro. However, it is currently unknown whether PPD or OA can attenuate cognitive deficits by enhancing hippocampal neurogenesis in vivo in a transgenic APP/PS1 AD mouse model. Here, we administered PPD or OA to APP/PS1 mice and monitored the effects on cognition and hippocampal neurogenesis. Methods: We used the Morris water maze, Y maze, and open field tests to compare the cognitive capacities of treated and untreated APP/PS1 mice. We investigated hippocampal neurogenesis using Nissl staining and BrdU/NeuN double labeling. NSC proliferation was quantified by Sox2 labeling of the hippocampal dentate gyrus. We used western blotting to determine the effects of PPD and OA on Wnt/GSK3β/β-catenin pathway activation in the hippocampus. Results: Both PPD and OA significantly ameliorated the cognitive impairments observed in untreated APP/PS1 mice. Furthermore, PPD and OA significantly promoted hippocampal neurogenesis and NSC proliferation. At the mechanistic level, PPD and OA treatments resulted in Wnt/GSK-3β/β-catenin pathway activation in the hippocampus. Conclusion: PPD and OA ameliorate cognitive deficits in APP/PS1 mice by enhancing hippocampal neurogenesis, achieved by stimulating the Wnt/GSK-3β/β-catenin pathway. As such, PPD and OA are promising novel therapeutic agents for the treatment of AD and other neurodegenerative diseases.

• Food Engineering Progress
• /
• v.23 no.4
• /
• pp.283-289
• /
• 2019

This study was performed to determine the effect of psyllium husk addition on the physical properties of rice extrudates. Rice-based formulations mixed with psyllium husk (0, 7, 14 and 21%) were extruded at a die temperature of 140℃, screw speed of 200 rpm, and moisture content of 20%. As the content of psyllium husk increased, expansion ratio decreased, while piece density and specific length increased. Apparent elastic modulus, breaking strength, adhesiveness, and hardness augmented with an elevation in psyllium husk content. Lightness declined as psyllium husk content furthered, while redness, yellowness, and color difference intensified. Water soluble index and water absorption index increased with an increased amount of psyllium husk. In conclusion, the addition of psyllium affected the expansion of extruded rice snack possessing hard texture, small cells, and sticky texture due to higher water absorption during hydration.

• Journal of Microbiology and Biotechnology
• /
• v.31 no.2
• /
• pp.207-216
• /
• 2021

Supplement of high-protein food plays an important role in improving the symptoms of malnutrition and the immune capacity of the body, but the association of high-protein diet and gut microbiota remained unaddressed. Here, we systematically analyzed the internal organs and gut microbiota in C57(WT) or PD-1H-depleted (KO) mice (T cells were activated) fed with pupae or feed for six weeks. We observed that the body weight gain in the mice fed with pupae increased less significantly than that of the feed group, while the villi and small intestine lengths in the pupa group were reduced compared with that of mice given feed. However, the average body weight of the KO mice increased compared with that of the WT mice fed with pupae or feed. Pupae increased the concentration of blood glucose in WT, but not in KO mice. Moreover, in the feed group, there was no difference in the weight of the internal organs between the WT and KO mice, but in the pupae-fed group, liver weight was decreased and spleen weight was increased compared with that of KO mice. The amounts/plural/amounts of Melainabacteria, Chloroflexi, and Armatimonadetes were specifically upregulated by pupae, and this upregulation was weakened or eliminated by PD-1H depletion. Some bacteria with high abundance in the feed-fed KO mice, such as Deferribacteres, Melainabacteria, Acidobacteria, Bacteroidetes, Spirochaetes and Verrucomicrobia, were decreased in pupae-fed KO mice, and Proteobacteria and Deinococcus were specifically enriched in pupae-fed KO mice. Bacteroidetes, Firmicutes and Akkermansia were associated with weight loss in the pupae-fed group while Lachnospiraceae and Anaerobiospirillum were related glucose metabolism and energy consumption. Based on high-throughput sequencing, we discovered that some gut bacteria specifically regulated the metabolism of a high-protein diet, and PD-1H deficiency improved life quality and sustained blood glucose. Moreover, PD-1H responses to high-protein diet through modulating the type and quantity of gut bacteria. These findings provide evidence about the association among gut microbiota, T cell activation (for PD-1H depletion) and high-protein diet metabolism, have important theoretical significance for nutrition and health research.

• Journal of Life Science
• /
• v.32 no.12
• /
• pp.956-961
• /
• 2022

Plant Chloroplast have several advantages as an expression platform of biopharmaceuticals over conventional expression platforms such as mammalian cells, yeast and bacteria. First, plants do not serve as a host for mammalian infectious virus and have endotoxin like bacteria which can cause anaphylactic shock. In addition, high copy number of chloroplast genome allows for chloroplast transformants to reach the high level of expression of heterologous genes. Moreover, the integration of transgenes into specific region of chloroplast genomes makes chloroplast transformants unaffected by positional effect which can be frequently observed from nuclear transformants, resulting in loss of transgene expressions. Antimicrobial peptides (AMPs) are a kind of innate immunity which is found from bacteria to humans. Unlike conventional antibiotics, very less dosage of AMPs can have catastrophic effect on bacterial survival. Further, the repeated use of AMPs does not trigger the development of bacterial resistance. Moricin, one of the AMPs, was isolated from Bombyx mori, a silkworm moth. The C-terminal of moricin consists largely of basic amino acids, and the N-terminal has an α-helix structure. Moricin was chosen and expressed in a SUMO/SUMOase without leaving any unwanted amino acids which could potentially affect the anti-bacterial activity of the moricin. The transformation vector used in this study has already been created in this lab for the expression in both prokaryotic systems such as E. coli and chloroplast. The expressed moricin was purified using Ni columns and SUMOase, and the antibacterial activity of the purified moricin was confirmed using an agar diffusion assay.

• Journal of the Korean Society of Radiology
• /
• v.17 no.3
• /
• pp.375-384
• /
• 2023

Most Hepatic hemangiomas are asymptomatic and small in size, making them difficult to find by pathological examination. Therefore, radiological diagnosis is essential for the early finding and diagnosis of Hepatic hemangioma. Three-phase method using contrast medium in computed tomography, T1, T2-weighted imaging in magnetic resonance imaging, dynamic magnetic resonance imaging using contrast medium, echo planar imaging method, diffusion-weighted imaging method, blood pool scan using ^99mTc-labeled red blood cells in nuclear medicine, we looked at the color doppler method In ultrasound, and it is important to accurately understand the imaging findings of hepatic hemangioma and perform the examination in order to make an accurate diagnosis. most hepatic hemangioma are benign tumors, care should be taken not to confuse them with malignant tumors such as hepatocellular carcinoma to prevent unnecessary procedures. Therefore, in order to make an accurate diagnosis, it is important to accurately understand the imaging findings of hemangioma and perform the examination.