• Tuberculosis and Respiratory Diseases
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• v.45 no.6
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• pp.1236-1251
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• 1998

Background : TNF-$\alpha$ appears to be a central mediator of the host response to sepsis. While TNF-$\alpha$ is mainly considered a proinflammatory cytokine, it can also act as a direct cytotoxic cytokine. However, there are not so many studies about the relationship bet ween TNF-$\alpha$ level and lung injury severity in ALI, particularly regarding the case of ALI caused by direct lung injury such as diffuse pulmonary infection. Recently, a natural defense mechanism, known as the stress response or the heat shock response, has been reported in cellular or tissue injury reaction. There are a number of reports examining the protective role of pre-induced heat stress proteins on subsequent LPS-induced TNF-$\alpha$ release from monocyte or macrophage and also on subsequent LPS-induced ALI in animals. However it is not well established whether the stress protein synthesis such as HSP can be induced from rat alveolar macrophages by in vitro or in vivo LPS stimulation. Methods : We measured the level of TNF-$\alpha$, the percentage of inflammatory cells in bronchoalveolar lavage fluid, protein synthesis in alveolar macrophages isolated from rats at 1, 2, 3, 4, 6, 12, and 24 hours after intratracheal LPS instillation. We performed histologic examination and also obtained histologic lung injury index score in lungs from other rats at 1, 2, 3, 4, 6, 12, 24 h after intratracheal LPS instillation. Isolated non-stimulated macrophages were incubated for 2 h with different concentration of LPS (0, 1, 10, 100 ng/ml, 1, or 10 ${\mu}g/ml$). Other non-stimulated macrophages were exposed at $43^{\circ}C$ for 15 min, then returned to at $37^{\circ}C$ in 5% CO2-95% for 1 hour, and then incubated for 2 h with LPS (0, 1, 10, 100ng/ml, 1, or 10 ${\mu}g/ml$). Results : TNF-$\alpha$ levels began to increase significantly at 1 h, reached a peak at 3 h (P<0.0001), began to decrease at 6 h, and returned to control level at 12 h after LPS instillation. The percentage of inflammatory cells (neutrophils and alveolar macrophages) began to change significantly at 2 h, reached a peak at 6 h, began to recover but still showed significant change at 12 h, and showed insignificant change at 24 h after LPS instillation compared with the normal control. After LPS instillation, the score of histologic lung injury index reached a maximum value at 6 h and remained steady for 24 hours. 35 kDa protein band was newly synthesized in alveolar macrophage from 1 hour on for 24 hours after LPS instillation. Inducible heat stress protein 72 was not found in any alveolar macrophages obtained from rats after LPS instillation. TNF-$\alpha$ levels in supernatants of LPS-stimulated macro phages were significantly higher than those of non-stimulated macrophages(p<0.05). Following LPS stimulation, TNF-$\alpha$ levels in supernatants were significantly lower after heat treatment than in those without heat treatment (p<0.05). The inducible heat stress protein 72 was not found at any concentrations of LPS stimulation. Whereas the 35 kDa protein band was exclusively found at dose of LPS of 10 ${\mu}g/ml$. Conclusion : TNF-$\alpha$ has a direct or indirect close relationship with lung injury severity in acute lung injury or acute respiratory distress syndrome. In vivo and in vitro LPS stimulation dose not induce heat stress protein 72 in alveolar macrophages. It is likely that 35 kDa protein, synthesized by alveolar macrophage after LPS instillation, does not have a defense role in acute lung injury.

• Journal of Life Science
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• v.32 no.11
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• pp.865-871
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• 2022

Tenebrio molitor larvae is well known as edible insect. Then, although it has been widely studied that Tenebrio molitor larvae has various bioactive functions such as antioxidant, anti-wrinkle, and anticancer. Nevertheless, antioxidant effects of Tenebrio molitor larvae water extract (TMH) has not been well described in Adult Retina Pigment Epithelial cell line (ARPE-19). In this study, we demonstrated that antioxidant effects of TMH against H₂O₂-induced oxidative stress in ARPE-19. Thus, we selected for our studies and performed a series of dose-response assay to determine the working concentration that lead to a consistent and high degree of cytotoxicity, which we defined as the level of H₂O₂ that killed 40% of the ARPE-19 cells. ARPE-19 cells were pre-treated with various concentrations of TMH (0.1 up to 2 mg/ml) before exposure to 300 µM H₂O₂. As we expected, TMH effectively prevented ARPE-19 cells from 300 µM H₂O₂-induced cell death in a dose-dependent manner. Furthermore, TMH inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs) such as extracellular signal regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38. Overall, the inhibitory effects of TMH on H₂O₂-induced apoptosis and oxidative stress were associated with the protection cleaved caspase-3, Bax, Bcl-2, and HO-1. The TMH suppressed H₂O₂-induced cell membrane leakage and oxidative stress in ARPE-19 cells. Thus, these results suggest that the TMH plays an important role in antioxidant effect in ARPE-19.

• The korean journal of orthodontics
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• v.33 no.3 s.98
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• pp.169-183
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• 2003

Tooth movement by orthodontic force effects great tissue changes within the periodontium, especially by shifting the blood flow in the pressure side and resulting in a hypoxic state of low oxygen tension. The aim of this study is to elucidate the possible mechanism of apoptosis in response to hypoxia in MC3T3El osteoblasts, the main cells in bone remodeling during orthodontic tooth movement. MC3T3El osteoblasts under hypoxic conditions ($2\%$ orygen) resulted in apoptosis in a time-dependent manner as estimated by DNA fragmentation assay and nuclear morphology stained with fluorescent dye, Hoechst 33258. Pretreatment with Z-VAD-FMK, a pancaspase inhibitor, or Z-DEVD-CHO, a specific caspase-3 inhibitor, completely suppressed the DNA ladder in response to hypoxia. An increase in caspase-3-like protease (DEVDase) activity was observed during apoptosis, but no caspase-1 activity (YVADase) was detected. To confirm what caspases are involved in apoptosis, Western blot analysis was performed using anti-caspase-3 or -6 antibodies. The 10-kDa protein, corresponding to the active products of caspase-3, and the 10-kDa protein of the active protein of caspase-6 were generated in hypoxia-challenged cells in which the processing of the full length form of caspase-3 and -6 was evident. While a time course similar to this caspase-3 and -6 activation was evident, hypoxic stress caused the cleavage of lamin A, which was typical of caspase-6 activity. In addition, the stress elicited the release of cytochrome c into the cytosol during apoptosis. Furthermore, we observed that pre-treatment with SB203580, a selective p38 mitogen activated protein kinase inhibitor, attenuated the hypoxia-induced apoptosis. The addition of SB203S80 suppressed caspase-3 and -6-like protease activity by hypoxia up to $50\%$. In contrast, PD98059 had no effect on the hypoxia-induced apoptosis. To confirm the involvement of MAP kinase, JNK/SAPK, ERK, or p38 kinase assay was performed. Although p38 MAPK was activated in response to hypoxic treatment, the other MAPK -JNK/SAPK or ERK- was either only modestly activated or not at all. These results suggest that p38 MAPK is involved in hypoxia-induced apoptosis in MC3T3El osteoblasts.

• Journal of Life Science
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• v.31 no.9
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• pp.818-826
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• 2021

5-Aminolevulinic acid phosphate (5-ALA-p) is a substance obtained by eluting 5-ALA (a natural delta amino acid) with aqueous ammonia, adding phosphoric acid to the eluate, and then adding acetone to confer properties suitable for use in photodynamic therapy applications. However, its pharmacological efficacy, including potential mechanisms of antioxidant and anti-inflammatory reactions, remains unclear. This study aimed to investigate the effects of 5-ALA-p on oxidative and inflammatory stresses in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Our data showed that 5-ALA-p significantly inhibited excessive phagocytic activity via LPS and attenuated oxidative stress in LPS-treated RAW 264.7 cells. Furthermore, 5-ALA-p improved mitochondrial biogenesis reduced by LPS, suggesting that 5-ALA-p restores mitochondrial damage caused by LPS. Additionally, 5-ALA-p significantly suppressed the release of nitric oxide (NO) and pro-inflammatory cytokines, such as tumor necrosis factor α (TNF-α), interleukin (IL)-1β, and IL-6, which are associated with the inhibition of inducible NO synthase and respective cytokine expression. Furthermore, 5-ALA-p reduced the nuclear translocation of nuclear factor-kappa B (NF-κB) and inhibited phosphorylation of mitogen-activated protein kinases (MAPKs), indicating that the anti-inflammatory effect of 5-ALA-p is mediated through the suppression of NF-κB and MAPK signaling pathways. Based on these results, 5-ALA-p may serve as a potential candidate to reduce inflammation and oxidative stress.

• Journal of Life Science
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• v.33 no.12
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• pp.1002-1014
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• 2023

The root of Cirsium japonicum var. maackii (Maxim.) has long been used in traditional medicine to prevent the onset and progression of various diseases and has been reported to exert a wide range of physiological effects, including antioxidant activity. However, research on its effects on hepatocytes remains scarce. This study used the human hepatocellular carcinoma HepG2 cell line to investigate the antioxidant activity of ethanol extract of C. japonicum root (EECJ) on hepatocytes. Hydrogen peroxide (H₂O₂) was used to mimic oxidative stress. The results showed that EECJ significantly reverted the decrease in cell viability and suppressed the release of lactate dehydrogenase in HepG2 cells treated with H₂O₂. Moreover, an analysis of changes in cell morphology, flow cytometry, and microtubule-associated protein light chain 3 (LC3) expression showed that EECJ significantly inhibited HepG2 cell autophagy induced by H₂O₂. Furthermore, it attenuated H₂O₂-induced apoptosis and cell cycle disruption by blocking intracellular reactive oxygen species and mitochondrial superoxide production, indicating strong antioxidant activity. EECJ also restored the decreased levels of intracellular glutathione (GSH) and enhanced the expression and activity of superoxide dismutase and GSH peroxidase in H₂O₂-treated HepG2 cells. Although an analysis of the components contained in EECJ and in vivo validation using animal models are needed, these findings indicate that EECJ is a promising candidate for the prevention and treatment of oxidative stress-induced liver cell damage.

• Journal of Life Science
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• v.29 no.1
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• pp.9-17
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• 2019

As tumors develop, they encounter microenvironmental stress, such as hypoxia and glucose depletion, due to poor vascular function, thereby leading to necrosis, which is observed in solid tumors. Necrotic cells are known to release cellular cytoplasmic contents, such as high mobility group box 1 (HMGB1), into the extracellular space. The release of HMGB1, a proinflammatory and tumor-promoting cytokine, plays an important role in promoting inflammation and metabolism during tumor development. Recently, HMGB1 was shown to induce the epithelial-mesenchymal transition (EMT) and metastasis. However, the underlying mechanism of the HMGB1-induced EMT, invasion, and metastasis is unclear. In this study, we showed that noninvasive breast cancer cells MCF-7 formed tightly packed, rounded spheroids and that the cells in the inner regions of a multicellular tumor spheroid (MTS), an in vitro model of a solid tumor, led to necrosis due to an insufficient supply of O2 and glucose. In addition, after 7 d of MTS culture, the EMT was induced via the transcription factor Snail. We also showed that HMGB1 receptors, including RAGE, TLR2, and TLR4, were induced by MTS culture. RAGE, TLR2, and TLR4 shRNA inhibited MTS growth, supporting the idea that RAGE/TLR2/TLR4 play critical roles in MTS growth. They also prevented MTS culture-induced Snail expression, pointing to RAGE/TLR2/TLR4-dependent Snail expression. RAGE, TLR2, and TLR4 shRNA suppressed the MTS-induced EMT. In human cancer tissues, high levels of RAGE, TLR2, and TLR4 were detected. These findings demonstrated that the HMGB-RAGE/TLR2/TLR4-Snail axis played a crucial role in the growth of the MTS and MTS culture-induced EMT.

• Journal of Nutrition and Health
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• v.54 no.6
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• pp.618-630
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• 2021

Purpose: The ginger rhizome (Zingiber officinale) is widely cultivated as a spice for its aromatic and pungent components. One of its constituents, 6-hydroxydopamine (6-OHDA) is usually thought to cross the cell membrane through dopamine uptake transporters, and induce inhibition of mitochondrial respiration and the generation of intracellular reactive oxygen species (ROS). This study examines the neuroprotective effect and acetylcholinesterase (AChE) inhibitory activity of fermented ginger extracts (FGEs) on 6-OHDA induced toxicity in SH-SY5Y human neuroblastoma cells. Methods: Ginger was fermented using 2 species of Bacillus subtilis, with or without enzyme pretreatment. Each sample was extracted with 70% ethanol. Neurotoxicity was assessed by applying the EZ-Cytox cell viability assay and by measuring lactic dehydrogenase (LDH) release. Morphological changes of apoptotic cell nuclei were observed by Hoechst staining. Cell growth and apoptosis of SH-SY5Y cells were determined by Western blotting and enzyme activity analysis of caspase-3, and AChE enzymatic activity was determined by the colorimetric assay. Results: In terms of cell viability and LDH release, exposure to FGE showed neuroprotective activities against 6-OHDA stimulated stress in SH-SY5Y cells. Furthermore, FGE reduced the 6-OHDA-induced apoptosis, as determined by Hoechst staining. The occurrence of apoptosis in 6-OHDA treated cells was confirmed by determining the caspase-3 activity. Exposure to 6-OHDA resulted in increased caspase-3 activity of SH-SY5Y cells, as compared to the unexposed group. However, pre-treatment with FGE inhibited the activity of caspase-3. The neuroprotective effects of FGE were also found to be caspase-dependent, based on reduction of caspase-3 activity. Exposure to FGE also inhibited the activity of AChE induced by 6-OHDA, in a dose-dependent manner. Conclusion: Taken together, our results show that FGE exhibits a neuroprotective effect in 6-OHDA treated SH-SY5Y cells, thereby making it a potential novel agent for the prevention or treatment of neurodegenerative disease.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.7
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• pp.1035-1043
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• 2014

To investigate the effect of dietary Acanthopanax senticosus polysaccharide (ASPS) on growth performance, immunity, blood parameters and mRNA expression of pro-inflammatory cytokines in immunologically challenged piglets, an experiment employing $2{\times}2$ factorial arrangement concerning dietary ASPS treatment (0 or 800 mg/kg) and immunological challenge (lipopolysaccharide [LPS] or saline injection) was conducted with 64 crossbred piglets (weaned at 28 d of age, average initial body weight of $7.25{\pm}0.21kg$) assigned to two dietary ASPS treatments with 8 replicates of 4 pigs each. Half of the piglets of per dietary treatment were injected with LPS or saline on d 14. Blood samples were obtained at 3 h after immunological injection on d 14 and piglets were slaughtered to obtain spleen samples on d 21. Dietary ASPS did not affect average daily gain (ADG) (p = 0.634), average daily feed intake (ADFI) (p = 0.655), and gain:feed (p = 0.814) prior to LPS challenge. After LPS challenge, for LPS-challenged pigs those fed ASPS had higher ADG and ADFI than the non-supplemented group (p<0.05), and an interaction between $LPS{\times}ASPS$ was observed on the two indices (p<0.05). Dietary ASPS improved lymphocyte proliferation among saline-injected and LPS-injected pigs (p<0.05). Interaction between $LPS{\times}ASPS$ was also revealed on lymphocyte proliferation (p<0.05). Circulatory concentration of IgG was influenced neither by ASPS (p = 0.803) or LPS (p = 0.692), nor their interaction (p = 0.289). Plasma concentration and spleen mRNA expression of interleukin-1beta (IL-$1{\beta}$), interleukin-6 (IL-6), and tumor necrosis factor (TNF)-${\alpha}$ were induced to increase (p<0.05) by LPS challenge, in contrast, these indices were decreased by dietary ASPS (p<0.05), and interactions were found on these cytokines (p<0.05). For LPS-challenged pigs, dietary ASPS also reduced the circulating concentration and spleen mRNA expression of IL-$1{\beta}$, IL-6 as well as TNF-${\alpha}$ (p<0.05). The interaction between $LPS{\times}ASPS$ was also observed on the circulating concentration of insulin-like growth factor-I, ${\alpha}$-acid glycoprotein (${\alpha}$-AGP), nonesterified fatty acid, and glucose (p<0.05). The results of this study demonstrate that dietary ASPS can modulate the release of pro-inflammatory cytokines during immunological challenge, which might enable piglets to achieve better growth performance.

• Corrosion Science and Technology
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• v.8 no.2
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• pp.62-67
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• 2009

Ti and Ti-alloys have good biocompatibility, appropriate mechanical properties and excellent corrosion resistance. However, the widely used Ti-6Al-4V is found to release toxic ions (Al and V) into the body, leading to undesirable long-term effects. Ti-6Al-4V has much higher elastic modulus (100 GPa) than cortical bone (20 GPa). Therefore, titanium alloys with low elastic modulus have been developed as biomaterials to minimize stress shielding. The electrochemical behavior of surface-modified and MC3T3-E1 cell-cultured Ti-30(Nb,Ta) alloys with low elastic modulus have been investigated using various electrochemical methods. Surfaces of test samples were treated as follows: $0.3{\mu}m$ polished; $25{\mu}m$, $50{\mu}m$ and $125{\mu}m$ sandblasted. Specimen surfaces were cultured with MC3T3-E1 cells for 2 days. Average surface roughness ($R_a$) and morphology of specimens were determined using a surface profilometer, OM, and FE-SEM. Corrosion behavior was investigated using a potentiostat(EG&G PARSTAT 2273), and electrochemical impedance spectroscopy was performed (10 mHz to 100 kHz) in 0.9% NaCl solution at $36.5{\pm}1^{\circ}C$. The microstructures of the Ti-30(Ta,Nb) alloys had a needle-like appearance. The $R_a$ of polished Ti-30Ta and Ti-30Nb alloys was lower than that of the sandblasted Ti alloy. Cultured cells displayed round shapes. For polished alloy samples, cells were well-cultured on all surfaces compared to sandblasted alloy samples. In sandblasted and cell-cultured Ti-30(Nb,Ta) alloy, the pitting potential decreased and passive current density increased as $R_a$ increased. Anodic polarization curves of cell-cultured Ti alloys showed unstable behavior in the passive region compared to non-cell-cultured alloys. From impedance tests of sandblasted and cell-cultured alloys, the polarization resistance decreased as $R_a$ increased, whereas, $R_a$ for cell-cultured Ti alloys increased compared to non-cell-cultured Ti alloys.

• Journal of the Korean Geotechnical Society
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• v.28 no.7
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• pp.5-16
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• 2012

Soil-nailing is the most popular method of reinforcing for slope stability. In general, two factors are considered as failure modes during the soil-nailing design stages: pullout failure mode and shear failure mode that will occur on the most probable failure plane. In many cases, however, shallow failure can also occur when the ground near the slope face is swept away by the horizontal stress release during the staged top-down excavation. In this paper, an optimized soil-nailing design methodology is proposed by considering the three failure modes mentioned above: pullout failure; shear failure; and shallow failure. The variables to be optimized include the bonded length and number of soil-nailings, and the confining pressure that should be applied at the slope face. The procedure to obtain the optimized design variables is as follows: at first, optimization of soil-nailings, i.e. bonded length and number, against pullout and shear failure modes; and then, optimization of confining pressure at each excavation stage that is needed to prevent shallow failure. Since the two processes are linked with each other, they are repeated until the optimized design variables can be obtained satisfying all the constrained design requirements in both of the two processes.