• Natural Product Sciences
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• v.25 no.4
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• pp.298-303
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• 2019

This study investigated the cytotoxic effects and mechanism of action of asiatic acid in pancreatic cancer cell lines. First, we confirmed the cell viability of MIA PaCa-2 and PANC-1 cells after asiatic acid administration for 48 and 72 h. The viability of MIA PaCa-2 and PANC-1 cells decreased in a dose-dependent manner following asiatic acid administration. To investigate the underlying mechanism, we performed a terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, annexin V assay, and western blotting. Asiatic acid induced apoptosis and autophagy through activation of AMP-activated protein kinase (AMPK) and inhibition of mammalian target of rapamycin (mTOR) in MIA PaCa-2 cells. Finally, the expression of miR-17 and miR-21, known as oncogenes in pancreatic cancer, was decreased by asiatic acid. These results indicate that asiatic acid has potential as a new therapeutic agent against pancreatic cancer.

• Animal Bioscience
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• v.35 no.6
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• pp.847-857
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• 2022

Objective: The effects of maternal undernutrition during midgestation on muscle fiber histology, myosin heavy chain (MyHC) expression, methylation modification of myogenic factors, and the mammalian target of rapamycin (mTOR) signaling pathway in the skeletal muscles of prenatal and postnatal goats were examined. Methods: Twenty-four pregnant goats were assigned to a control (100% of the nutrients requirement, n = 12) or a restricted group (60% of the nutrients requirement, n = 12) between 45 and 100 days of gestation. Descendants were harvested at day 100 of gestation and at day 90 after birth to collect the femoris muscle tissue. Results: Maternal undernutrition increased (p<0.05) the fiber area of the vastus muscle in the fetuses and enhanced (p<0.01) the proportions of MyHCI and MyHCIIA fibers in offspring, while the proportion of MyHCIIX fibers was decreased (p<0.01). DNA methylation at the +530 cytosine-guanine dinucleotide (CpG) site of the myogenic factor 5 (MYF5) promoter in restricted fetuses was increased (p<0.05), but the methylation of the MYF5 gene at the +274,280 CpG site and of the myogenic differentiation (MYOD) gene at the +252 CpG site in restricted kids was reduced (p<0.05). mTOR protein signals were down-regulated (p<0.05) in the restricted offspring. Conclusion: Maternal undernutrition altered the muscle fiber type in offspring, but its relationship with methylation in the promoter regions of myogenic genes needs to be elucidated.

• The Journal of Pediatrics of Korean Medicine
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• v.34 no.4
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• pp.22-30
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• 2020

Objectives This study was conducted to confirm the inhibitory effect of β-glucan on epithelial inflammation induced by atopic dermatitis through Endocannabinoid system (ECS) activity. Methods Six-week-old NC/Nga mice were divided into a control group (Ctrl), atopic dermatitis elicitation group (ADE), and a β-glucan-treated group (β-glucan treatment after atopy dermatitis elicitation, β-GT). After 3 weeks, CB1, CB2, and GPR55 were observed to confirm the regulation of ECS activity, and filaggrin in the stratum corneum and Kallikrein-related peptidase (KLK) 7 in the stratum corneum and protease activated receptor (PAR)-2 were observed to confirm the inhibition of the inflammation, Phosphorylated extracellular signal-related kinase (p-ERK), Phosphorylated mammalian target of rapamycin (p-mTOR), and E-Cadherin were observed to confirm microenvironmental regulation. Results β-GT was significantly increased in CB1, CB2, and GPR55 positive reactions compared to that of the ADE. In positive reaction of the filaggrin in the stratum corneum, β-GT was significantly increased than that of the ADE. For KLK7 positive and PAR2 positive, β-GT was significantly reduced compared to the ADE. The p-ERK-positive and p-mTOR-positive reactions were significantly reduced in β-GT than in ADE. E-cadherin positive reaction was significantly increased in β-GT than in ADE (All p < 0.01). Conclusions It was confirmed that β-glucan has the effect of inhibiting the epithelium induced by atopic dermatitis through the ECS activity.

• Journal of Microbiology and Biotechnology
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• v.33 no.12
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• pp.1635-1647
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• 2023

Muscle atrophy, which is defined as a decrease in muscle mass and strength, is caused by an imbalance between the anabolism and catabolism of muscle proteins. Thus, modulating the homeostasis between muscle protein synthesis and degradation represents an efficient treatment approach for this condition. In the present study, the protective effects against muscle atrophy of ethanol extracts of Morus alba L. (MA) and Angelica keiskei Koidz. (AK) leaves and their mixtures (MIX) were evaluated in vitro and in vivo. Our results showed that MIX increased 5-aminoimidazole-4-carboxamide ribonucleotide-induced C2C12 myotube thinning, and enhanced soleus and gastrocnemius muscle thickness compared to each extract alone in dexamethasone-induced muscle atrophy Sprague Dawley rats. In addition, although MA and AK substantially improved grip strength and histological changes for dexamethasone-induced muscle atrophy in vivo, the efficacy was superior in the MIX-treated group. Moreover, MIX further increased the expression levels of myogenic factors (MyoD and myogenin) and decreased the expression levels of E3 ubiquitin ligases (atrogin-1 and muscle-specific RING finger protein-1) in vitro and in vivo compared to the MA- and AK-alone treatment groups. Furthermore, MIX increased the levels of phosphorylated phosphoinositide 3-kinase (PI3K), protein kinase B (Akt), and mammalian target of rapamycin (mTOR) that were reduced by dexamethasone, and downregulated the expression of forkhead box O3 (FoxO3a) induced by dexamethasone. These results suggest that MIX has a protective effect against muscle atrophy by enhancing muscle protein anabolism through the activation of the PI3K/Akt/mTOR signaling pathway and attenuating catabolism through the inhibition of FoxO3a.

• Biomolecules & Therapeutics
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• v.25 no.6
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• pp.609-617
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• 2017

Pancreatic cancer is one of the most lethal and aggressive cancers in the world. However, no effective treatment is currently available for pancreatic cancer. The objective of this study was to determine the anti-pancreatic cancer effect of ${\alpha}$-mangostin (${\alpha}M$) and ${\gamma}$-mangostin (${\gamma}M$) extracted from the pericarp of Garcinia mangostana L.. Both ${\alpha}$M and ${\gamma}M$ reduced the viability of pancreatic cancer cells MIA PaCa-2 and PANC-1 in a dose-dependent manner. These compounds induced apoptosis by increasing c-PARP and c-Caspase 3 levels. They also induced autophagy by increasing levels of microtubule-associated protein 1A/1B light chain 3B (LC3II) in both cell lines while decreasing sequestosome 1 (p62) in MIA PaCa-2. Both ${\alpha}$M and ${\gamma}M$ induced autophagy through increasing phosphorylation levels of AMP-activated protein kinase (p-AMPK) and p38-mitogen activated protein kinase (p-p38) while decreasing phosphorylation level of mammalian target of rapamycin complex 1 (p-mTOR). Of various microRNAs (miRNA), miR-18a was found to be a putative regulatory miRNA for autophagy induced by ${\alpha}$M or ${\gamma}M$. In combination with gemcitabine, a compound frequently used in pancreatic cancer treatment, ${\alpha}$M and ${\gamma}M$ showed synergistic anti-cancer effects in MIA PaCa-2. Collectively, these results suggest that ${\alpha}$M and ${\gamma}M$ can induce apoptosis and autophagy in pancreatic cancer cells and that their anti-cancer effect is likely to be associated with miR-18a. In conclusion, ${\alpha}$M and ${\gamma}M$ might be used as a potential new therapy for pancreatic cancer.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.6
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• pp.1012-1022
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• 2020

Objective: Caseins and fatty acids of milk are synthesized and secreted by the epithelial cells of the mammary gland. All-trans retinoic acid (ATRA), an active metabolite of vitamin A, has been shown to promote mammary development. This study was conducted to determine the effect of ATRA on casein synthesis and fatty acid composition in MAC-T cells. Methods: MAC-T cells were allowed to differentiate for 4 d, treated with ATRA (0, 1.0, 1.5, and 2.0 μM), and incubated for 3 d. We analyzed the fatty acid composition, the mRNA expression of casein and fatty acid synthesis-related genes, and the phosphorylation of casein synthesis-related proteins of MAC-T cells by gas chromatography, quantitative polymerase chain reaction, and western blotting, respectively. Results: In MAC-T cells, ATRA increased the mRNA levels of α_S1-casein and β-casein, janus kinase 2 (JAK2) and E74-like factor 5 of the signal transducer and activator of transcription 5 β (STAT5-β) pathway, ribosomal protein S6 kinase beta-1 (S6K1) and eukaryotic translation initiation factor 4E binding protein 1 of the mammalian target of rapamycin (mTOR) pathway, inhibited the mRNA expression of phosphoinositide 3-kinase and eukaryotic initiation factor 4E of the mTOR pathway, and promoted the phosphorylation of STAT5-β and S6K1 proteins. Additionally, ATRA increased the de novo synthesis of fatty acids, reduced the content of long-chain fatty acids, the ratio of monounsaturated fatty acids to saturated fatty acids (SFA), the ratio of polyunsaturated fatty acids (PUFA) to SFA, and the ratio of ω-6 to ω-3 PUFA. The mRNA levels of acetyl-CoA carboxylase 1, fatty acid synthase, lipoprotein lipase, stearoyl-CoA desaturase, peroxisome proliferator-activated receptor gamma, and sterol regulatory element-binding protein 1 (SREBP1) were enhanced by ATRA. Conclusion: ATRA promotes the synthesis of casein by regulating JAK2/STAT5 pathway and downstream mTOR signaling pathway, and it improves the fatty acid composition of MAC-T cells by regulating SREBP1-related genes.

• Animal Bioscience
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• v.37 no.3
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• pp.509-521
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• 2024

Objective: It was shown that microRNAs (miRNAs) play an important role in milk protein synthesis. However, the post-transcriptional regulation of casein expression by exogenous miRNA (xeno-miRNAs) in ruminants remains unclear. This study explores the regulatory roles of alfalfa xeno-miR162 on casein synthesis in bovine mammary epithelial cells (bMECs). Methods: The effects of alfalfa xenomiR-162 and G protein subunit gamma 11 (GNG11) on proliferation and milk protein metabolism of bMECs were detected by 5-Ethynyl-2'-Deoxyuridine (EdU) staining, flow cytometry, cell counting kit-8 (CCK-8), enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction (qRT-PCR), and Western blot. Dual-luciferase reporter assay was used to verify the targeting relationship between GNG11 and xenomiR-162. Results: Results showed that over-expression of xenomiR-162 inhibited cell proliferation but promoted apoptosis, which also up-regulated the expression of several casein coding genes, including CSN1S1, CSN1S2, and CSN3, while decreasing the expression of CSN2. Furthermore, the targeting relationship between GNG11 and xenomiR-162 was determined, and it was confirmed that GNG11 silencing also inhibited cell proliferation but promoted apoptosis and reduced the expression of casein coding genes and genes related to the mammalian target of rapamycin (mTOR) pathway. Conclusion: Alfalfa xenomiR-162 appears to regulate bMECs proliferation and milk protein synthesis via GNG11 in the mTOR pathway, suggesting that this xeno-miRNA could be harnessed to modulate CSN3 expression in dairy cows, and increase κ-casein contents in milk.

• Journal of Animal Science and Technology
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• v.54 no.5
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• pp.369-373
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• 2012

AMP-activated protein kinase (AMPK) maintains energy homeostasis in skeletal muscle. Nonetheless, its functional role on protein synthesis with different nutrient availability has not been elucidated. Therefore, the purpose of this study is to examine the effect of AMPK activity on protein content in C2C12 myotubes incubated with low (5 mM; LG) or high (25 mM; HG) glucose media. LG stimulated (p<0.05) AMPK and acetyl CoA carboxylase (ACC) activity compare to those in HG group. Total protein content was higher in myotubes cultured with HG than in those cultured with LG and further increased by AICAR (5-amino-1-${\beta}$-D-ribofuranosyl-imidazole-4-carboxamide). Myotubes cultured with HG showed 7.5% lower UbFL (Ubiquitin Firefly Luciferase)-to-SV40 (Simian virus40) ratio compared to those in LG. Glucose level did not change the phosphorylation level of mammalian target of rapamycin (mTOR). Interestingly, administration of AICAR significantly increased phosphorylation level of mTOR in myotubes cultured with LG but not in those with HG. Overall, this data indicate that AMPK activity and protein turnover are finely regulated in response to different glucose concentration.

• Biomolecules & Therapeutics
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• v.22 no.4
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• pp.275-281
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• 2014

Autophagy is a series of catabolic process mediating the bulk degradation of intracellular proteins and organelles through formation of a double-membrane vesicle, known as an autophagosome, and fusing with lysosome. Autophagy plays an important role of death-survival decisions in neuronal cells, which may influence to several neurodegenerative disorders including Parkinson's disease. Chebulagic acid, the major constituent of Terminalia chebula and Phyllanthus emblica, is a benzopyran tannin compound with various kinds of beneficial effects. This study was performed to investigate the autophagy enhancing effect of chebulagic acid on human neuroblastoma SH-SY5Y cell lines. We determined the effect of chebulagic acid on expression levels of autophagosome marker proteins such as, DOR/TP53INP2, Golgi-associated ATPase Enhancer of 16 kDa (GATE 16) and Light chain 3 II (LC3 II), as well as those of its upstream pathway proteins, AMP-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR) and Beclin-1. All of those proteins were modulated by chebulagic acid treatment in a way of enhancing the autophagy. Additionally in our study, chebulagic acid also showed a protective effect against 1-methyl-4-phenylpyridinium ($MPP^+$) - induced cytotoxicity which mimics the pathological symptom of Parkinson's disease. This effect seems partially mediated by enhanced autophagy which increased the degradation of aggregated or misfolded proteins from cells. This study suggests that chebulagic acid is an attractive candidate as an autophagy-enhancing agent and therefore, it may provide a promising strategy to prevent or cure the diseases caused by accumulation of abnormal proteins including Parkinson's disease.

• Journal of Ginseng Research
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• v.47 no.2
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• pp.246-254
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• 2023

Background: Here, we aimed to assess the inhibitory effect of a new compound from Panax ginseng on the migration of human ovarian cancer cells and tube formation of human umbilical vein endothelial cells (HUVECs). Methods: A new compound, ginsenglactone A (1), was isolated from ginseng roots, together with seven known compounds (2-8). Spectroscopic data were used to elucidate the chemical structure of 1. The tubular structure formation in HUVECs was assessed by Mayer's hematoxylin staining. The migration of A2780 cells was evaluated using the scratch wound healing assay. Results: HUVECs treated with 1 had the statistically significant decrease in tubular structure formation compared to the HUVECs treated with compounds 2-8. This effect was enhanced by co-treatment with inhibitors for phosphatidylinositol 3-kinase (PI3K) (LY294002) and extracellular signal-regulated kinase (ERK) (U0126). Treatment with 1 decreased the expression of phosphorylation of ERK, PI3K, vascular endothelial growth factor receptor2 (VEGFR2), Akt, and mammalian target of rapamycin (mTOR). In addition, the ability of A2780 cells to cover the scratched area were also decreased. This effect was enhanced by co-treatment with U0126. Lastly, treatment with 1 decreased the phosphorylation of ERK, matrix metalloproteinase-9 (MMP-9), and MMP-2. Conclusion: These results suggest that ginsenglactone A is a potential inhibitor of HUVEC tubular structure formation and A2780 cellular migration, which may be helpful for understanding its anticancer mechanism.