• The Korean Journal of Physiology and Pharmacology
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• 제22권4호
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• pp.379-389
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• 2018

A nucleobase adenine is a fundamental component of nucleic acids and adenine nucleotides. Various biological roles of adenine have been discovered. It is not produced from degradation of adenine nucleotides in mammals but produced mainly during polyamine synthesis by dividing cells. Anti-inflammatory roles of adenine have been supported in IgE-mediated allergic reactions, immunological functions of lymphocytes and dextran sodium sulfate-induced colitis. However adenine effects on Toll-like receptor 4 (TLR4)-mediated inflammation by lipopolysaccharide (LPS), a cell wall component of Gram negative bacteria, is not examined. Here we investigated anti-inflammatory roles of adenine in LPS-stimulated immune cells, including a macrophage cell line RAW264.7 and bone marrow derived mast cells (BMMCs) and peritoneal cells in mice. In RAW264.7 cells stimulated with LPS, adenine inhibited production of pro-inflammatory cytokines $TNF-{\alpha}$ and IL-6 and inflammatory lipid mediators, prostaglandin $E_2$ and leukotriene $B_4$. Adenine impeded signaling pathways eliciting production of these inflammatory mediators. It suppressed $I{\kappa}B$ phosphorylation, nuclear translocation of nuclear factor ${\kappa}B$ ($NF-{\kappa}B$), phosphorylation of Akt and mitogen activated protein kinases (MAPKs) JNK and ERK. Although adenine raised cellular AMP which could activate AMP-dependent protein kinase (AMPK), the enzyme activity was not enhanced. In BMMCs, adenine inhibited the LPS-induced production of $TNF-{\alpha}$, IL-6 and IL-13 and also hindered phosphorylation of $NF-{\kappa}B$ and Akt. In peritoneal cavity, adenine suppressed the LPS-induced production of $TNF-{\alpha}$ and IL-6 by peritoneal cells in mice. These results show that adenine attenuates the LPS-induced inflammatory reactions.

• Journal of Acupuncture Research
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• 제28권1호
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• pp.1-14
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• 2011

목적 : 인진약침이 고지방식이로 유발된 비만 ICR mice에서 비만 및 동반 대사이상에 미치는 효과와 그 기전을 연구하고자 한다. 방법 : 인진약침의 비만 예방효과를 검증하기 위하여, 4주간 고지방식이를 급여하면서 150mg/kg 또는 300mg/kg의 인진약침을 양측 비수($BL_{20}$)에 교대로 매일 피하에 시술하였다. 또한 인진약침의 비만 치료효과를 검증하기 위하여, 4주간 고지방식이를 급여한 비만 ICR mice에 추가 4주간 고지방식이를 유지하면서 300 mg/kg 인진약침액과 vehicle control로써 등량의 distilled water를 양측 비수($BL_{20}$)에 교대로 매일 피하에 약침시술하였다. 인진약침의 항비만효과와 기전을 알아보기 위해, 체중, blood glucose, insulin, total cholesterol, triglyceride, non-esterified fatty acid (NEFA), AST, ALT levels 등 대사지표를 측정하고 부고환조직의 조직학적 관찰을 시행하였으며, AMPK activation과 adipocyte differentiation, fatty acid ${\beta}$-oxidation 및 thermogenesis와 관련된 gene expressions을 평가하였다. 결과 : 인진약침의 치료를 통하여 고지방식이 급여로 인한 체중의 증가가 억제되었을 뿐만 아니라, 비만 ICR mice의 체중을 감소시켰으며, glucose 및 lipid homeostasis를 개선시켰으며 지방조직의 증식을 억제하였다. AMPK의 phosphorylation과 CPT-1 및 UCP2의 발현을 증가시켰으며, PPAR-${\gamma}$, C/EBP${\alpha}$, aP2, LPL,FAS, SCD-1의 발현을 억제하였다. 결론 : 인진약침은 고지방식이 유도 동물모델에서 비만 및 동반 대사이상을 개선시키는 효과가 있으며, 이는 식이억제에 의한 2차적 효과라기 보다는 energy expenditure를 증가시키고, pre-adipocyte differentiation 및 proliferation을 억제하며, lipogenesis를 억제하고 lipolysis를 증가시키는 효과에 의한 것으로 사료된다.

• Nutrition Research and Practice
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• 제11권3호
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• pp.180-189
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• 2017

BACKGROUND/OBJECTIVES: Recent living condition improvements, changes in dietary habits, and reductions in physical activity are contributing to an increase in metabolic syndrome symptoms including diabetes and obesity. Through such societal developments, humankind is continuously exposed to metabolic diseases such as diabetes, and the number of the victims is increasing. This study investigated Cordyceps militaris water extract (CMW)-induced glucose uptake in HepG2 cells and the effect of CMW treatment on glucose metabolism. MATERIALS/METHODS: Colorimetric assay kits were used to determine the glucokinase (GK) and pyruvate dehydrogenase (PDH) activities, glucose uptake, and glycogen content. Either RT-PCR or western blot analysis was performed for quantitation of glucose transporter 2 (GLUT2), hepatocyte nuclear factor 1 alpha ($HNF-1{\alpha}$), phosphatidylinositol 3-kinase (PI3k), protein kinase B (Akt), phosphorylated AMP-activated protein kinase (pAMPK), phosphoenolpyruvate carboxykinase, GK, PDH, and glycogen synthase kinase 3 beta ($GSK-3{\beta}$) expression levels. The ${\alpha}-glucosidase$ inhibitory activities of acarbose and CMW were evaluated by absorbance measurement. RESULTS: CMW induced glucose uptake in HepG2 cells by increasing GLUT2 through $HNF-1{\alpha}$ expression stimulation. Glucose in the cells increased the CMW-induced phosphorylation of AMPK. In turn, glycolysis was stimulated, and glyconeogenesis was inhibited. Furthermore, by studying the mechanism of action of PI3k, Akt, and $GSK-3{\beta}$, and measuring glycogen content, the study confirmed that the glucose was stored in the liver as glycogen. Finally, CMW resulted in a higher level of ${\alpha}-glucosidase$ inhibitory activity than that from acarbose. CONCLUSION: CMW induced the uptake of glucose into HepG2 cells, as well, it induced metabolism of the absorbed glucose. It is concluded that CMW is a candidate or potential use in diabetes prevention and treatment.

• 한국식품과학회지
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• 제52권1호
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• pp.81-88
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• 2020

PGSE의 혈당조절 효과를 평가하기 위하여 제2형 당뇨 동물모델을 이용하여 8주간의 동물실험을 진행한 결과, 고농도 PGSE(600 mg/kg)의 투여는 경구 포도당 내성 및 혈당 수준을 유의적으로 감소시켰으며(p<0.05), 당화혈색소도 유의적으로 낮은 수준을 유지시켰다(p<0.05). 또한, 혈청 인슐린과 렙틴 농도 역시 대조군과 비교하여 PGSE 고농도 처리군에서 유의적으로 감소하였다(p<0.05). PGSE 투여는 db/db 마우스의 골격근에서 인슐린 의존적 세포신호전달경로를 유의적으로 활성화시켰으며, AMPK 인산화를 촉진시키고, 골격근내 포도당 흡수를 위한 GLUT4의 세포막으로의 전이를 대조군 대비 약 1.7배 증가시켰다. 이러한 결과를 근거로 할 때 PGSE는 항 당뇨병 치료제로서의 잠재적 가능성을 가진 것으로 판단된다.

• Biomolecules & Therapeutics
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• 제20권2호
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• pp.220-225
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• 2012

To develop a ginseng product possessing an efficacy for diabetes, ginseng radix ethanol extract was treated with pectinase and obtained the GINST. In the present study, we evaluate the beneficial effect of GINST on high fat diet (HFD)-induced hyperglycemia and hyperlipidemia and action mechanism(s) in ICR mice. The mice were randomly divided into five groups: regular diet group (RD), high fat diet group (HFD), HFD plus GINST at 75 mg/kg (GINST75), 150 mg/kg (GINST150), and 300 mg/kg (GINST300). Oral glucose tolerance test reveals that GINST improves the glucose tolerance after glucose challenge. Fasting plasma glucose and insulin levels were decreased by 4.3% and 4.2% in GINST75, 10.9% and 20.0% in GINST150, and 19.6% and 20.9% in GINST300 compared to those in HFD control group. Insulin resistance indices were also markedly decreased by 8.2% in GINST75, 28.7% in GINST150, and 36.4% in GINST300, compared to the HFD control group. Plasma triglyceride, total cholesterol and non-esterified fatty acid levels in the GINST300 group were decreased by 13.5%, 22.7% and 24.1%, respectively, compared to those in HFD control group. Enlarged adipocytes of HFD control group were markedly decreased in GINST-treated groups, and shrunken islets of HFD control mice were brought back to near normal shape in GINST300 group. Furthermore, GINST enhanced phosphorylation of AMP-activated protein kinase (AMPK) and glucose transporter 4 (GLUT4). In summary, GINST prevents HFD-induced hyperglycemia and hyperlipidemia through reducing insulin resistance via activating AMPK-GLUT4 pathways, and could be a potential therapeutic agent for type 2 diabetes.

• Nutrition Research and Practice
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• 제15권5호
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• pp.568-578
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• 2021

BACKGROUND/OBJECTIVES: Psidium guajava L. (guava) leaves have been shown to exhibit hypoglycemic and antidiabetic effects in rodents. This study investigated the effects of guava leaf extract on adipogenesis, glucose uptake, and lipolysis of adipocytes to examine whether the antidiabetic properties are mediated through direct effects on adipocytes. MATERIALS/METHODS: 3T3-L1 cells were treated with 25, 50, 100 ㎍/mL of methanol extract from guava leaf extract (GLE) or 0.1% dimethyl sulfoxide as a control. Lipid accumulation was evaluated with Oil Red O Staining and AdipoRed assay. Immunoblotting was performed to measure the expression of adipogenic transcription factors, fatty acid synthase (FAS), and AMP-activated protein kinase (AMPK). Glucose uptake under basal or insulin-stimulated condition was measured using a glucose analog 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino]-2-deoxy-D-glucose. Lipolysis from fully differentiated adipocytes was measured by free fatty acids release into the culture medium in the presence or absence of epinephrine. RESULTS: Oil Red O staining and AdipoRed assay have shown that GLE treatment reduced lipid accumulation during adipocyte differentiation. Mitotic clonal expansion, an early essential event for adipocyte differentiation, was inhibited by GLE treatment. GLE inhibited the expression of transcription factors involved in adipocyte differentiation, such as peroxisome proliferator-activated receptor 𝛄 (PPAR𝛄), CCAAT/enhancer-binding protein α (C/EBPα), and sterol regulatory element-binding protein-1c (SREBP-1c). FAS expression was also decreased while the phosphorylation of AMPK was increased by GLE treatment. In addition, GLE increased insulin-induced glucose uptake into adipocytes. In lipid-filled mature adipocytes, GLE enhanced epinephrine-induced lipolysis but reduced basal lipolysis dose-dependently. CONCLUSIONS: The results show that GLE inhibits adipogenesis and improves adipocyte function by reducing basal lipolysis and increasing insulin-stimulated glucose uptake in adipocytes, which can be partly associated with antidiabetic effects of guava leaves.

• 대한한의학방제학회지
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• 제30권4호
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• pp.269-280
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• 2022

Objectives : In this study, it was investigated the effects of solid-phase fermentation extraction with Phellinus linteus of discarded Schisandra chinensis extract (PS) and its action mechanism on dexamethasone-induced muscle atrophy in mice. Methods : In mice, muscle atrophy model was induced by dexamethasone (5 mg/kg, I.p) once daily for 2 weeks and with PS extract administration (100 and 300 mg/kg, p.o.) as treatment groups. The changes in body weights, grip strength, Treadmill test, muscle weights, and the expression of atrophy-related genes were measured in muscle atrophy mice. The histological changes of gastrocnemius tissues were also observed by H&E staining with measurement of myofiber size. Results : The administration of PS extract increased significantly body weights, grip strength, treadmill test and muscle weights in muscle atrophy mice. PS extract administration increased significantly the area of myofibers and inhibited structural damages of muscle and increased significantly the expression of myogenin and decreased significantly the expression of MuRF1, Atrogin1 and phosphorylation of AMPK and PGC1α in muscle tissues of muscle atrophy mice. Conclusions : These results indicate that PS extract has a improvement effects on muscle atrophy with stimulation of myogenic differentiation and inhibition of mRNA degradation that could be related with the activation of AMPK and PGC1α signaling pathways in muscle. This suggests that PS extract can apply to treat muscle atrophy in clinics.

• 대한본초학회지
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• 제29권4호
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• pp.77-82
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• 2014

Objectives : The effects of ethanol extract of Plantago asiatica L. were investgated on adipocyte differentiation, lipopogenesis, lipolysis and apoptosis using differnentiated 3T3-L1 adipocytes. Methods : Plantago asiatica L. was extracted with ethanol (CCE). We carried on MTT assay for cell proliferation, Oil Red O staining for determination of cell differentiation and intracelluar adipogenesis. TUNEL staining assay for cell apoptosis, and Western blot analysis for measurement of pAMPK and pACC, $C/EBP{\alpha}$, $PPAR{\gamma}$ protein expressions were performed. Results : The addition of CCE up to 0.2 mg/ml into cell culture media showed no cytotoxicity. Treatment of 0.2 mg/ml CCE significantly inhibited differentiation in 3T3-L1 preadipocytes. Lipid accumulation of the CCE treated cells was decreased compared with that of control. Induction of cell apoptosis was increased in CCE treated cells compared with that of control. AMPK and ACC levels of the cells with 0.2 mg/ml CCE were led to phosphorylation and also expressions of $C/EBP{\alpha}$ and $PPAR{\gamma}$, as adipogenic transcription factors, were suppressed compared with those of control. Conclusions : Taken together, these results provide evidence that CCE has a regulatory role in lipid metabolism that is related to differentiation into adipocytes, adipogenesis and apoptosis.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2023년도 임시총회 및 춘계학술대회
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• pp.55-55
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• 2023

With the COVID-19 pandemic, there is increasing interest in anti-obesity strategies. According to the National Statistical Office, the obesity rate in Korea was 38.3% in 2020 and 37.1% in 2021. Obesity is a risk factor for several severe diseases, including stroke, heart disease, type 2 diabetes, and certain types of cancer. Pinus rigida × Pinus taeda is a hybrid of Pinus rigida Mill and Pinus taeda Linn, and its cones are considered a by-product. Although previous studies have investigated their pharmacological effects on antioxidant activity and protection against oxidative DNA damage, few researchers have explored their potential as functional natural materials. Therefore, we evaluated the anti-obesity effects of the cone of ethyl acetate fraction of P. rigida × P. taeda (ERT), specifically its ability to inhibit lipid accumulation. Our analysis showed that ERT contains phytochemicals (catechin and caffeic acid) which are known to improve immune function and inhibit cell damage. ERT inhibited lipid droplet accumulation at the cellular levels through Oil Red O staining. Furthermore, ERT suppressed the expression of adipogenic transcription factors (PPARγ and CEBP/α) as well as downstream lipogenic target genes (FAS and SREBP-1) thereby inhibiting adipogenesis. ERT also down-regulated key adipogenic markers, including aP2α, while inducing the phosphorylation of AMPK. It has been reported that PPARγ and CEBP/α are expressed in the early stages of adipose differentiation, while SREBP-1 is expressed in the late stage. Therefore, our findings suggest that ERT activates AMPK signaling pathways, which inhibits adipogenic transcription factors (PPARγ, C/EBPα, and SREBP1) and lipogenic genes (FAS and aP2α), thereby blocking lipid accumulation and preventing obesity and related disorders. ERT showed potential as a new resource for developing a functional material for anti-obesity agents.

• 대한한의학방제학회지
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• 제31권4호
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• pp.283-293
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• 2023

Objectives : Native to East Asia, Japan, and Korea, Cinnamomum japonicum Siebold (CJ) is renowned for its aromatic leaves and bark. We previously assessed the antioxidant activity of fractionated CJ branches (CJB:70% EtOH extract), including hexane (CJB1), chloroform (CJB2), ethyl acetate (CJB3), butanol (CJB4), and water (CJB5). Our findings revealed that CJB3 exhibited the highest antioxidant activity. Here, we aimed to investigate whether CJB3 possesses cytoprotective effects and induces the activity of antioxidant enzymes in hepatocytes. Methods : As HepG2 cells were the first to exhibit the key characteristics of hepatocytes, we investigated the hepatoprotective effects of CJB3 on HepG2 cells. Results : Before conducting the cell experiment, we checked that CJB3, up to a concentration of 100 ㎍/mL, did not exhibit cytotoxicity toward HepG2 cells. ROS production increased because of t-BHP treatment decreased in a concentration-dependent manner upon CJB3 treatment. We confirmed that CJB3 inhibited t-BHP-induced cell death. CJB3 was found to reverse the expression of proteins associated with t-BHP-induced apoptosis. We also observed that CJB3 induced Nrf2 phosphorylation and the nuclear translocation of Nrf2. And, CJB3 treatment caused a time-dependent enhancement of GCL and NQO1 protein expression. We further confirmed that CJB3 increased the expression of Nrf2 target genes, and this effect was associated with the activation of JNK, p38, and AMPK. Conclusion : CJB3 prevents t-BHP-induced oxidative stress and apoptosis and enhances the expression of Nrf2 target genes via JNK, p38, and AMPK activation. These results suggest that CJB3 is a promising candidate for the treatment of liver diseases.