1.A study of the lipoprotein lipase inhibitory mechanism of Poncirus trifoliata water extracts.
Sung Mee LEE ; Yun Hwan KANG ; Kyoung Kon KIM ; Tae Woo KIM ; Myeon CHOE
Journal of Nutrition and Health 2015;48(1):9-18
PURPOSE: Poncirus trifoliata has been reported to have anti-inflammatory, antioxidant, and immune activities. However, its anti-obesity activity and the mechanism by which the water extract of dried, immature fruit of Poncirus trifoliata (PF-W) acts are not clear. This study suggests a potential mechanism associated with the anti-obesity activity of PF-W. METHODS: We measured the effect of PF-W on lipoprotein lipase (LPL) regulation using enzyme-linked immunosorbent assay (ELISA) and an activity assay. The LPL regulation mechanism was examined by reverse transcription polymerase chain reaction (RT-PCR) to measure the mRNA expression of biomarkers related to protein transport and by western blot for analysis of the protein expression of the transcription factor CCAAT-enhancer-binding protein (C/EBPbeta) RESULTS: The total polyphenol and flavonoid content of PF-W was 52.15 +/- 4.02 and 6.56 +/- 0.47 mg/g, respectively. PF-W treatment decreased LPL content in media to 58 +/- 5% of that in control adipocyte media, and increased LPL content to 117 +/- 3.5% of that in control adipocytes, but did not affect the mRNA expression of LPL. PF-W also increased the mRNA expression of sortilin-related receptor (SorLA), a receptor that induces endocytosis and intracellular trafficking of LPL, in a concentration- and time-dependent manner. Finally, cell fractionation revealed that PF-W treatment induced the expression of C/EBPbeta, a SorLA transcription factor, in the nuclei of 3T3-L1 adipocytes. CONCLUSION: The LPL secretion and activity assay showed PF-W to be an LPL secretion inhibitor, and these results suggest the potential mechanism of PF-W involving inhibition of LPL secretion through C/EBPbeta-mediated induction of SorLA expression.
Adipocytes
;
Biomarkers
;
Blotting, Western
;
CCAAT-Enhancer-Binding Proteins
;
Cell Fractionation
;
Endocytosis
;
Enzyme-Linked Immunosorbent Assay
;
Fruit
;
Lipoprotein Lipase*
;
Polymerase Chain Reaction
;
Poncirus*
;
Protein Transport
;
Reverse Transcription
;
RNA, Messenger
;
Transcription Factors
;
Water*
2.Antiobesity effects of the water-soluble fraction of the ethanol extract of Smilax china L. leaf in 3T3-L1 adipocytes.
Yun Hwan KANG ; Kyoung Kon KIM ; Dae Jung KIM ; Myeon CHOE
Nutrition Research and Practice 2015;9(6):606-612
BACKGROUND/OBJECTIVES: Several medicinal properties of Smilax china L. have been studied including antioxidant, anti-inflammatory, and anti-cancer effects. However, the antiobesity activity and mechanism by which the water-soluble fraction of this plant mediates its effects are not clear. In the present study, we investigated the lipolytic actions of the water-soluble fraction of Smilax china L. leaf ethanol extract (wsSCLE) in 3T3-L1 adipocytes. MATERIALS/METHODS: The wsSCLE was identified by measuring the total polyphenol and flavonoid content. The wsSCLE was evaluated for its effects on cell viability, lipid accumulation, glycerol, and cyclic adenosine monophosphate (cAMP) contents. In addition, western blot analysis was used to evaluate the effects on protein kinase A (PKA), PKA substrates (PKAs), and hormone-sensitive lipase (HSL). For the lipid accumulation assay, 3T3-L1 adipocytes were treated with different doses of wsSCLE for 9 days starting 2 days post-confluence. In other cell experiments, mature 3T3-L1 adipocytes were treated for 24 h with wsSCLE. RESULTS: Results showed that treatment with wsSCLE at 0.05, 0.1, and 0.25 mg/mL had no effect on cell morphology and viability. Without evidence of toxicity, wsSCLE treatment decreased lipid accumulation compared with the untreated adipocyte controls as shown by the lower absorbance of Oil Red O stain. The wsSCLE significantly induced glycerol release and cAMP production in mature 3T3-L1 cells. Furthermore, protein levels of phosphorylated PKA, PKAs, and HSL significantly increased following wsSCLE treatment. CONCLUSION: These results demonstrate that the potential antiobesity activity of wsSCLE is at least in part due to the stimulation of cAMP-PKA-HSL signaling. In addition, the wsSCLE-stimulated lipolysis induced by the signaling is mediated via activation of the beta-adrenergic receptor.
3T3-L1 Cells
;
Adenosine Monophosphate
;
Adipocytes*
;
Blotting, Western
;
Cell Survival
;
China*
;
Cyclic AMP-Dependent Protein Kinases
;
Ethanol*
;
Glycerol
;
Lipolysis
;
Plants
;
Smilax*
;
Sterol Esterase
3.Fatty acid analysis and regulatory effects of citron (Citrus junos Sieb. ex TANAKA) seed oil on nitric oxide production, lipid accumulation, and leptin secretion.
Tae Woo KIM ; Kyoung Kon KIM ; Yun Hwan KANG ; Dae Jung KIM ; Myeon CHOE
Journal of Nutrition and Health 2014;47(4):221-228
PURPOSE: Citron seed oil (CSO) has been reported to have high antioxidant activity. However, the composition and other biologically activities of CSO have not been reported. In this study, we confirmed the fatty acid composition of CSO, which may be beneficial to vascular disease and obesity. METHODS: We investigated the oil composition of CSO using gas chromatography coupled with mass spectrometry (GC-MS) analysis, and cytotoxicity was confirmed by Cell Counting Kit-8 (CCK-8) assay. Nitric oxide (NO) production in human umbilical vein endothelial cells (HUVECs) was measured using Griess reagent, and lipid accumulation and leptin secretion in 3T3-L1 cells were measured by Oil-Red O staining and commercial ELISA kit, respectively. RESULTS: GC-MS analysis indicated that CSO contains several components, including linoleic acid, oleic acid, palmitic acid, stearic acid, linolenic acid, palmitoleic acid, and arachidic acid. In physiological activity analysis, CSO did not induce cytotoxic effects in HUVECs and 3T3-L1 cells. Further, CSO significantly induced nitric oxide and leptin secretion as well as inhibited lipid accumulation. CONCLUSION: CSO increased NO release, inhibited lipid accumulation, and induced leptin secretion, suggesting it may be useful for the management of vessels and weight gain. Although further studies are required to investigate the safety and mechanism of action of CSO, our results show that the composition and physiological activity of CSO are sufficient for its use as functional edible oil.
3T3-L1 Cells
;
alpha-Linolenic Acid
;
Cell Count
;
Chromatography, Gas
;
Enzyme-Linked Immunosorbent Assay
;
Human Umbilical Vein Endothelial Cells
;
Leptin*
;
Linoleic Acid
;
Mass Spectrometry
;
Nitric Oxide*
;
Obesity
4.Mode of Onset of Paroxysmal Atrial Fibrillation during 24 hour Holter Monitoring.
Weon Jung JEON ; Jeong Chul SEO ; Hainan PIAO ; Gi Byoung NAM ; Kang Hyeon CHOE ; Seogjae LEE ; Jong Myeon HONG ; Dong Woon KIM ; Myeong Chan CHO
Korean Circulation Journal 2000;30(4):457-467
BACKGROUND: Paroxysmal atrial fibrillation (PAF) causes not only severe symptoms and hemodynamic changes, but may progress to chronic atrial fibrillation. Autonomic nervous system or atrial premature beat (APB) has been suggested to contribute to the spontaneous initiation of PAF, but the exact mechanism has been largely unknown. METHODS: One hundred and twenty nine episodes of PAF lasting longer than 5 sec were analyzed in 18 patients (M:F=11:?). Two minutes of normal sinus rhythm before the onset of PAF, and the initial one minute of PAF were printed and analyzed. RESULTS: Most of PAFs were initiated by APBs (38%) or rapid atrial tachycardias (AT, 59%). The frequency of APBs tended to increase immediately before PAF onset (p=0.08). The coupling intervals and coupling indices were not significantly different between PAF-producing APBs and benign APBs. More than half of PAF episodes were initiated by rapid ATs (rate, 357+/-50 bpm). After the onset, they accelerated over several seconds and then degenerated into AF. In some cases, transition from AF to atrial flutter and vice versa were observed. Heart rate, measured at 60-second intervals during 2 minutes before PAF onset, did not change significantly (p=0.44). CONCLUSION: Most of PAFs were initiated by APBs or rapid ATs. Heart rate did not change significantly but the frequency of APBs tended to increase immediately before PAF onset. Rapid ATs frequently accelerated and degenerated into AF. In this regard, Holter monitoring could be useful in identifying patients with PAF triggered by rapid ATs.
Atrial Fibrillation*
;
Atrial Flutter
;
Autonomic Nervous System
;
Cardiac Complexes, Premature
;
Electrocardiography, Ambulatory*
;
Heart Rate
;
Hemodynamics
;
Humans
;
Tachycardia
5.Study of the mechanisms underlying increased glucose absorption in Smilax china L. leaf extract-treated HepG2 cells.
Yun Hwan KANG ; Dae Jung KIM ; Kyoung Kon KIM ; Sung Mee LEE ; Myeon CHOE
Journal of Nutrition and Health 2014;47(3):167-175
PURPOSE: Previous studies have shown that treatment with Smilax china L. leaf extract (SCLE) produces antidiabetic effects due to alpha-glucosidase inhibition. In this study, we examined the mechanism underlying these antidiabetic effects by examining glucose uptake in HepG2 cells cultured with SCLE. METHODS: Glucose uptake and glucokinase activity were examined using an assay kit. Expression of glucose transporter (GLUT)-2, GLUT-4, and HNF-1alpha was measured by RT-PCR or western blot. RESULTS: Treatment with SCLE resulted in enhanced glucose uptake in HepG2 cells, and this effect was especially pronounced when cells were cultured in an insulin-free medium. SCLE induced an increase in expression of GLUT-2 but not GLUT-4. The increase in the levels of HNF-1alpha, a GLUT-2 transcription factor, in total protein extract and nuclear fraction suggest that the effects of SCLE may occur at the level of GLUT-2 transcription. In addition, by measuring the change in glucokinase activity following SCLE treatment, we confirmed that SCLE stimulates glucose utilization by direct activation of this enzyme. CONCLUSION: These results demonstrate that the potential antidiabetic activity of SCLE is due at least in part to stimulation of glucose uptake and an increase in glucokinase activity, and that SCLE-stimulated glucose uptake is mediated through enhancement of GLUT-2 expression by inducing expression of its transcription factor, HNF-1alpha.
Absorption*
;
alpha-Glucosidases
;
Blotting, Western
;
China*
;
Glucokinase
;
Glucose Transport Proteins, Facilitative
;
Glucose*
;
Hep G2 Cells*
;
Hepatocyte Nuclear Factor 1-alpha
;
Smilax*
;
Transcription Factors
6.Erratum: Funding Acknowledgment.
Mi Ja CHUNG ; Jeong Mi KIM ; Sangchul LEE ; Taewoo KIM ; Daejung KIM ; Jongmi BAEK ; Taehyuk KIM ; Jaesung LEE ; Kyoungkon KIM ; Jin A YOON ; Myeon CHOE
Nutrition Research and Practice 2012;6(3):270-270
The funding acknowledgment in this article was omitted as published.
7.Comparison of antioxidant, alpha-glucosidase inhibition and anti-inflammatory activities of the leaf and root extracts of Smilax china L..
Kyoung Kon KIM ; Yun Hwan KANG ; Dae Jung KIM ; Tae Woo KIM ; Myeon CHOE
Journal of Nutrition and Health 2013;46(4):315-323
This study was conducted in order to compare the biological activities of leaf and root water extracts of Smilax china L. (SC) by measuring the total polyphenol and flavonoid contents, anti-oxidant activity, inhibitory effect on alpha-glucosidase, and anti-inflammatory gene expression. The total polyphenol and flavonoid contents of SC leaf (SCLE) and root (SCRE) water extracts were 127.93 mg GAE/g and 39.50 mg GAE/g and 41.99 mg QE/g and 1.25 mg QE/g, respectively. The anti-oxidative activities of SCLE and SCRE were measured using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity assay and reducing power assay. Both SCLE and SCRE scavenged radicals in a concentration-dependent manner, and SCLE showed stronger radical scavenging activity and reducing power than SCRE; however, both SCLE and SCRE exhibited lower activities than ascorbic acid. Compared to the anti-diabetic drug acarbose, which was used as a positive control, SCLE and SCRE exhibited low alpha-glucosidase inhibition activities; nevertheless, the activity of SCLE was 3.7 fold higher than that of SCRE. Finally, SCLE caused significantly decreased expression of the LPS-induced cytokines, iNOS, and COX-2 mRNA in RAW264.7 cells, indicating anti-inflammatory activity. These results indicate that SCLE might be a potential candidate as an anti-oxidant, anti-diabetic, and anti-inflammatory agent.
Acarbose
;
alpha-Glucosidases
;
Ascorbic Acid
;
Biphenyl Compounds
;
China
;
Cytokines
;
Gene Expression
;
Picrates
;
RNA, Messenger
;
Smilax
;
Water
8.Erratum: Funding Acknowledgment.
Jongmi BAEK ; Jaesung LEE ; Kyoungkon KIM ; Taewoo KIM ; Daejung KIM ; Cheonan KIM ; Kanazawa TSUTOMU ; Sarangowa OCHIR ; Kooyeon LEE ; Cheol Ho PARK ; Yong Jik LEE ; Myeon CHOE
Nutrition Research and Practice 2013;7(3):242-242
The funding acknowledgment in this article was omitted as published.
9.Effects of medicinal herb water extracts on expression of hepatic glucokinase, pyruvate dehydrogenase and acetyl-CoA carboxylase mRNA.
Hyun Sook KIM ; Tae Woo KIM ; Dae Jung KIM ; Jae Sung LEE ; Myeon CHOE
The Korean Journal of Nutrition 2013;46(2):119-125
We studied the anti-diabetic effects of medicinal herb water extracts on expression of hepatic glucokinase (GCK), pyruvate dehydrogenase (PDH), and acetyl-CoA carboxylase (ACC) mRNA. The medicinal herbs used for experiments were Cornus officinalis (CO), Paeonia suffruticosa Andrews (PSA), Discorea japonica Thunb. (DJ), Rehmannia glutinosa (RG), Lycium chinense (LC), and Pyrus pyrifolia (PP). For GCK mRNA expression, CO, RG, and LC water extracts exhibited a more effective activity than other extracts. Cells treated with RG and LC water extracts showed an increase in expression of PDH mRNA to 191% and 124%, respectively, compared to control. Expression of ACC mRNA was significantly higher in LC water extract. These data indicate that CO, RG, and LC water extracts stimulates expression of hepatic GCK, PDH, and ACC mRNA.
Acetyl Coenzyme A
;
Acetyl-CoA Carboxylase
;
Cornus
;
Glucokinase
;
Lycium
;
Oxidoreductases
;
Paeonia
;
Plants, Medicinal
;
Pyrus
;
Pyruvic Acid
;
Rehmannia
;
RNA, Messenger
;
Water
10.Anti-Oxidative and Anti-Inflammatory Effect of Water Extract from Perillae semen in RBL-2H3 Cells.
Jeong Mi KIM ; Dae Jung KIM ; Tae Hyuk KIM ; Hyun Sook KIM ; Myeon CHOE
The Korean Journal of Nutrition 2010;43(4):367-373
The present study was to investigate anti-oxidative and anti-inflammatory activity of Perillae semen in RBL-2H3 basophilic leukemia cells. Inhibitory effect of Perillae semen onto free radical generation was determined by measuring DPPH and hydroxyl radical scavenging activities in vitro. Anti-inflammatory actions of Perillae semen extracts (100, 250, 500 microgram/mL) were assessed by testing their effects on the degranulation of mast cells. For this, beta-hexosaminidase released from RBL-2H3 cells was used and proinflammatory cytokines were measured by an ELISA kit. Our results indicated that Perillae semen water extracts effectively inhibited free radical generation. At the concentration of 500 microgram/mL of water extract, the degranulation of RBL-2H3 cells were inhibited by 42.1%. The IgE-antigen complex increased the accumulation of IL-4 and TNF-alpha secretion in RBL-2H3 cells and treatments with 250 and 500 microgram/mL of Perillae semen extracts suppressed the IgE induced secretion of IL-4 and TNF-alpha protein by 20.5, 26.9% and 14.5, 16.5% respectively. We observed that Perillae semen water extract reduced beta-hexosaminidase, IL-4, and TNF-alpha secretion in RBL-2H3 cells. These results provide that Perillae semen may be beneficial in the treatment of allergic inflammatory disease.
Basophils
;
beta-N-Acetylhexosaminidases
;
Cytokines
;
Enzyme-Linked Immunosorbent Assay
;
Hydroxyl Radical
;
Immunoglobulin E
;
Interleukin-4
;
Leukemia
;
Mast Cells
;
Perilla
;
Semen
;
Tumor Necrosis Factor-alpha
;
Water