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1.
Exp Biol Med (Maywood) ; 248(20): 1695-1707, 2023 10.
Article En | MEDLINE | ID: mdl-37646261

Resistin and suppressors of cytokine signaling (SOCSs) have been reported to regulate prostate cancer (PCa) cell proliferation and survival, respectively. Whether any of the SOCS molecules mediate the mitogenic effect of resistin on PCa cells is unknown. Using PC-3 human PCa cells, we found that resistin upregulates the expression of SOCS3 and SOCS5 mRNA, but not SOCS7 mRNA, in a dose- and time-dependent manner. The resistin-induced increases in SOCS3 and SOCS5 expression and cell proliferation were prevented by pretreatment with specific inhibitors of the TLR4, ERK, p38 MAPK, JNK, PI3K, and JAK2 proteins. However, pretreatment with a TLR2 inhibitor had no effect on resistin-mediated SOCS3 and SOCS5 expression. In addition, the effects of resistin on SOCS3, SOCS5, and SOCS7 mRNA levels were cell type-specific. Overexpression of either SOCS3 or SOCS5 enhanced further resistin-stimulated growth of PC-3 cells, whereas silencing SOCS3 or SOCS5 antagonized resistin-increased cell growth. Further PCa tissue analysis demonstrated higher levels of RETN, TLR4, SOCS3, and SOCS5 mRNAs in cancer tissues than benign prostate hyperplasia and indicated positive correlations among RETN, TLR4, and SOCS5. These data suggest that SOCS5, TLR4, and, to a lesser extent, SOCS3 can mediate the mitogenic effect of resistin on PC-3 PCa cells.


Prostate , Prostatic Neoplasms , Humans , Male , PC-3 Cells , Prostate/metabolism , Prostatic Neoplasms/metabolism , Resistin/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Suppressor of Cytokine Signaling 3 Protein/genetics , Suppressor of Cytokine Signaling 3 Protein/metabolism , Suppressor of Cytokine Signaling Proteins/genetics , Suppressor of Cytokine Signaling Proteins/metabolism , Toll-Like Receptor 4/metabolism
2.
Mol Nutr Food Res ; 67(9): e2200336, 2023 05.
Article En | MEDLINE | ID: mdl-36825504

SCOPE: This study investigates the effect of epigallocatechin gallate (EGCG) on white and beige preadipocyte growth and explores the involvement of the miR-let-7a/HMGA2 pathway. METHODS AND RESULTS: 3T3-L1 and D12 cells are treated with EGCG. The effect of EGCG on cell proliferation and viability is evaluated, as well as microRNA (miRNA)-related signaling pathways. EGCG inhibits 3T3-L1 and D12 preadipocyte growth, upregulates miR-let-7a expression, and downregulates high-mobility group AT-hook 2 (HMGA2) mRNA and protein levels in a time- and dose-dependent manner. In addition, overexpression of miR-let-7a significantly inhibits the growth of 3T3-L1 and D12 cells and decreases HMGA2 mRNA and protein levels. MiR-let-7a inhibitor antagonizes the inhibitory effects of EGCG on the number and viability of 3T3-L1 and D12 cells. Furthermore, miR-let-7a inhibitor reverses the EGCG-induced increase in miR-let-7a expression levels and decrease in HMGA2 mRNA and protein levels. HMGA2 overexpression induces an increase in cell number and viability and antagonizes EGCG-suppressed cell growth and HMGA2 expression in 3T3-L1 and D12 preadipocytes. CONCLUSION: EGCG inhibits the growth of 3T3-L1 and D12 preadipocytes by modulating the miR-let-7a and HMGA2 pathways.


Catechin , MicroRNAs , MicroRNAs/genetics , MicroRNAs/metabolism , Tea , Signal Transduction , Cell Proliferation , Catechin/pharmacology , RNA, Messenger
3.
Medicina (Kaunas) ; 58(5)2022 Apr 23.
Article En | MEDLINE | ID: mdl-35629994

Background and Objectives: Diabetes mellitus (DM) can cause macrovascular and microvascular complications, potentially resulting in further life-threatening complications. In general, the global prevalence of type 2 DM is increasing. To date, the care of DM comprises three aspects: diet, medication and exercise; among them, exercise is the most economical. Albuminuria is associated with renal injury and the progress of chronic kidney disease (CKD). The effects of habitual exercise in patients with new onset of diabetic kidney disease (DKD) have not been generally recognized. Our aim was to conduct an observational study regarding the effects of regular exercise on proteinuria and associated metabolic indices in patients with newly diagnosed type 2 DM. To investigate the effects of an exercise habit on albuminuria and the metabolic indices including renal function, blood glucose, and plasma lipids among patients with newly diagnosed type 2 DM. Materials and Methods: A cross-sectional study was conducted on newly diagnosed DM patients in two teaching hospitals in Taiwan from 1 June to 31 December 2020. The DM patients participated in the Diabetes Shared Care Network. According to the DM care mode, the patients' blood biochemical results were analysed. Based on exercise duration, the patients were divided into two groups, i.e., the exercise group (≥150 min per week) and the non-exercise group (<150 min per week). Clinical demographic features and laboratory examination including blood and urine biochemistries were determined. Results: A total of 229 patients including 99 males (43.2%) and 130 females (56.8%) participated in the study. The proportion of DM patients with normoalbuminuria was higher (p < 0.05) in the exercise group (69.8%) than in the non-exercise group (53.7%), and the proportion of DM patients with micro or macroalbuminuria was lower in the exercise group (30.2%) than in the non-exercise group (46.3%). Levels of glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), triglycerides (TG) and high-density lipoprotein (HDL) were significantly different in both groups. Compared with the non-exercise group, lower HbA1c (6.89 ± 0.69 vs. 7.16 ± 1.05%) (p < 0.05), lower FPG (121.9 ± 25.7 vs. 140.5 ± 42.4 mg/dL) (p < 0.05), lower TG (115.6 ± 53.6 vs. 150.2 ± 15.4 mg/dL) (p < 0.05), and higher HDL (50.3 ± 11.4 vs. 44.1 ± 9.26 mg/dL) (p < 0.05) levels were noted in the exercise group. Conclusions: Regular exercise remains imperative and may bear an impact on albuminuria, blood glucose, and plasma lipids among type 2 DM patients. Therefore, medical staff and healthcare providers should encourage patients to maintain an exercise duration ≥150 min per week for preventing and controlling DM progression.


Albuminuria , Diabetes Mellitus, Type 2 , Albuminuria/epidemiology , Blood Glucose/metabolism , Cross-Sectional Studies , Diabetes Mellitus, Type 2/complications , Exercise , Female , Glycated Hemoglobin , Habits , Humans , Lipids , Male
4.
Front Endocrinol (Lausanne) ; 12: 661828, 2021.
Article En | MEDLINE | ID: mdl-34093437

Endothelins induce many biological responses, and they are composed of three peptides: ET-1, ET-2, and ET-3. Reports have indicated that ET-1 regulates cell proliferation, adipogenesis, and other cell responses and that ET-3 stimulates the growth of gastrointestinal epithelial cells and melanocytes. However, the signalling pathways of ET3 that mediate the growth of fat cells are still unclear. Using 3T3-L1 white preadipocytes, we found that ET-3 induced increases in both cell number and BrdU incorporation. Pretreatment with an ETAR antagonist (but not an ETBR antagonist) blocked the ET-3-induced increases in both cell number and BrdU incorporation. Additionally, BQ610 suppressed the ET-3-induced increases in phosphorylation of AMPK, c-JUN, and STAT3 proteins, and pretreatment with specific inhibitors of AMPK, JNK/c-JUN, or JAK/STAT3 prevented the ET-3-induced increases in phosphorylation of AMPK, c-JUN, and STAT3, respectively. Neither p38 MAPK inhibitor nor PKC inhibitor altered the effects of ET-3 on cell growth. These data suggest that ET-3 stimulates preadipocyte growth through the ETAR, AMPK, JNK/c-JUN, and STAT3 pathways. Moreover, ET-3 did not alter HIB1B brown preadipocyte and D12 beige preadipocyte growth, suggesting a preadipocyte type-dependent effect. The results of this study may help explain how endothelin mediates fat cell activity and fat cell-associated diseases.


Adipocytes/cytology , Endothelin-3/metabolism , 3T3-L1 Cells , Adipocytes/metabolism , Animals , Cell Proliferation , Endothelin-3/antagonists & inhibitors , Mice , Mitogen-Activated Protein Kinases/metabolism , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Receptor, Endothelin A/metabolism , Receptor, Endothelin B/metabolism , Sphingomyelin Phosphodiesterase/metabolism
5.
Int J Mol Sci ; 21(23)2020 Dec 03.
Article En | MEDLINE | ID: mdl-33287214

Prostate cancer (PCa) is a reproductive system cancer in elderly men. We investigated the effects of betel nut arecoline on the growth of normal and cancerous prostate cells. Normal RWPE-1 prostate epithelial cells, androgen-independent PC-3 PCa cells, and androgen-dependent LNCaP PCa cells were used. Arecoline inhibited their growth in dose- and time-dependent manners. Arecoline caused RWPE-1 and PC-3 cell cycle arrest in the G2/M phase and LNCaP cell arrest in the G0/G1 phase. In RWPE-1 cells, arecoline increased the expression of cyclin-dependent kinase (CDK)-1, p21, and cyclins B1 and D3, decreased the expression of CDK2, and had no effects on CDK4 and cyclin D1 expression. In PC-3 cells, arecoline decreased CDK1, CDK2, CDK4, p21, p27, and cyclin D1 and D3 protein expression and increased cyclin B1 protein expression. In LNCaP cells, arecoline decreased CDK2, CDK4, and cyclin D1 expression; increased p21, p27, and cyclin D3 expression; had no effects on CDK1 and cyclin B1 expression. The antioxidant N-acetylcysteine blocked the arecoline-induced increase in reactive oxygen species production, decreased cell viability, altered the cell cycle, and changed the cell cycle regulatory protein levels. Thus, arecoline oxidant exerts differential effects on the cell cycle through modulations of regulatory proteins.


Areca/chemistry , Arecoline/pharmacology , Cell Cycle Checkpoints/drug effects , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Arecoline/chemistry , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Cell Survival/drug effects , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Dose-Response Relationship, Drug , Gene Expression Regulation, Neoplastic , Humans , Male , Prostatic Neoplasms
6.
Am J Physiol Cell Physiol ; 319(5): C839-C857, 2020 11 01.
Article En | MEDLINE | ID: mdl-32755450

Endothelin (ET)-1 regulates adipogenesis and the endocrine activity of fat cells. However, relatively little is known about the ET-1 signaling pathway in preadipocyte growth. We used 3T3-L1 preadipocytes to investigate the signaling pathways involved in ET-1 modulation of preadipocyte proliferation. As indicated by an increased number of cells and greater incorporation of bromodeoxyuridine (BrdU), the stimulation of preadipocyte growth by ET-1 depends on concentration and timing. The concentration of ET-1 that increased preadipocyte number by 51-67% was ~100 nM for ~24-48 h of treatment. ET-1 signaling time dependently stimulated phosphorylation of ERK, c-JUN, STAT3, AMPK, and PKCα/ßII proteins but not AKT, JNK, or p38 MAPK. Treatment with an ETAR antagonist, such as BQ610, but not ETBR antagonist BQ788, blocked the ET-1-induced increase in cell proliferation and phosphorylated levels of ERK, c-JUN, STAT3, AMPK, and PKCα/ßII proteins. In addition, pretreatment with specific inhibitors of ERK1/2 (U0126), JNK (SP600125), JAK2/STAT3 (AG490), AMPK (compound C), or PKC (Ro318220) prevented the ET-1-induced increase in cell proliferation and reduced the ET-1-stimulated phosphorylation of ERK1/2, c-JUN, STAT3, AMPK, and PKCα/ß. Moreover, the SphK antagonist suppressed ET-1-induced cell proliferation and ERK, c-JUN, STAT3, AMPK, and PKC phosphorylation, and the SMase2 antagonist suppressed ET-1-induced cell proliferation. However, neither the p38 MAPK antagonist nor the CerS inhibitor altered the effect of ET-1. The results indicate that ETAR, JAK2/STAT3, ERK1/2, JNK/c-JUN, AMPK, PKC, SphK, and SMase2, but not ETBR, p38 MAPK, or CerS, are necessary for the ET-1 stimulation of preadipocyte proliferation.


Adipocytes/drug effects , Endothelin-1/pharmacology , JNK Mitogen-Activated Protein Kinases/genetics , Protein Kinase C/genetics , STAT3 Transcription Factor/genetics , p38 Mitogen-Activated Protein Kinases/genetics , 3T3-L1 Cells , Adipocytes/cytology , Adipocytes/metabolism , Animals , Butadienes/pharmacology , Cell Differentiation , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Endothelin Receptor Antagonists/pharmacology , Extracellular Signal-Regulated MAP Kinases/genetics , Extracellular Signal-Regulated MAP Kinases/metabolism , Gene Expression Regulation , Imidazoles/pharmacology , JNK Mitogen-Activated Protein Kinases/metabolism , Mice , Nitriles/pharmacology , Oligopeptides/pharmacology , Phosphotransferases (Alcohol Group Acceptor)/genetics , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Piperidines/pharmacology , Protein Kinase C/metabolism , Pyridines/pharmacology , Receptors, Endothelin/genetics , Receptors, Endothelin/metabolism , STAT3 Transcription Factor/metabolism , Signal Transduction , Sphingomyelin Phosphodiesterase/genetics , Sphingomyelin Phosphodiesterase/metabolism , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors , p38 Mitogen-Activated Protein Kinases/metabolism
7.
J Acute Med ; 10(4): 156-160, 2020 Dec 01.
Article En | MEDLINE | ID: mdl-33489739

A 72-year-old woman with an ant bite on her hand presented with anaphylaxis at the scene and chest pain in the emergency department.Electrocardiography showed a myocardial infarction with inferior and lateral wall ST elevation. She received percutaneous coronary intervention. The results revealed left anterior descending branch and right coronary artery obstruction. After stenting, she was discharged in good condition. Kounis syndrome was diagnosed. Emergency physicians should be alert to acute coronary syndrome following anaphylaxis.

8.
Sci Rep ; 9(1): 4228, 2019 03 12.
Article En | MEDLINE | ID: mdl-30862805

Colorectal cancer (CRC) is the third leading cause of cancer-related death worldwide. We examined if tumor tissue and circulating protein levels of all vascular endothelial growth factors (VEGFs) and VEGF receptors (VEGFRs) were synchronous and different in Taiwan patients with metastatic CRC (mCRC) vs. non-mCRC. We analyzed samples from 109 patients enrolled from 2005-2017, 50 with stages I/II and 59 with stages III/IV CRC. We found that VEGF-A, -B, -C, -D, placental growth factor (PlGF), VEGFR-1, VEGFR-2, and VEGFR-3 were higher in tumor tissues than non-tumor tissues. Metastatic patients had higher levels of circulating VEGFs and soluble VEGFRs (sVEGFRs) than healthy subjects, as well as higher VEGF-A, -B, -C, -D, and PlGF proteins in both tumor tissue and serum than non-metastatic patients. Protein levels of VEGF and VEGFR were mainly associated with the patient's age, tumor site, tumor size, tumor stage, and lymph node metastasis. Patients exhibiting high levels of VEGF, VEGFR, and sVEGFR had a shorter overall survival and disease-free survival than those with low levels. We conclude that synchronous changes in VEGF and VEGFR levels in CRC tissue and serum VEGF can discriminate between metastatic and non-metastatic subjects and high levels are associated with poor survival in CRC.


Colorectal Neoplasms/blood , Colorectal Neoplasms/mortality , Neoplasm Proteins/blood , Vascular Endothelial Growth Factors/blood , Aged , Colorectal Neoplasms/pathology , Female , Humans , Lymphatic Metastasis , Male , Middle Aged
9.
PLoS One ; 13(7): e0200508, 2018.
Article En | MEDLINE | ID: mdl-30011295

The present study was designed to investigate the pathways involved in the effect of betel nut arecoline on cell viability in 3T3-L1 preadipocytes. Arecoline, but not arecaidine or guvacine, inhibited preadipocyte viability in a concentration- and time-dependent manner. Arecoline arrested preadipocyte growth in the G2/M phase of the cell cycle; decreased the total levels of cyclin-dependent kinase 1 (CDK1), p21, and p27 proteins; increased p53 and cyclin B1 protein levels; and had no effect on CDK2 protein levels. These results suggested that arecoline selectively affected a particular CDK subfamily. Arecoline inhibited AMP-activated protein kinase (AMPK) activity; conversely, the AMPK activator, AICAR, blocked the arecoline-induced inhibition of cell viability. Pre-treatment with the antioxidant, N-acetylcysteine, prevented the actions of arecoline on cell viability, G2/M growth arrest, reactive oxygen species (ROS) production, and the levels of CDK1, p21, p27, p53, cyclin B1, and phospho-AMPK proteins. These AMPK- and ROS-dependent effects of arecoline on preadipocyte growth may be related to the mechanism underlying the modulatory effect of arecoline on body weight.


AMP-Activated Protein Kinases/metabolism , Adipocytes/metabolism , Arecoline/pharmacology , G2 Phase Cell Cycle Checkpoints/drug effects , Reactive Oxygen Species/metabolism , 3T3-L1 Cells , Adipocytes/cytology , Animals , Cell Cycle Proteins/biosynthesis , Gene Expression Regulation/drug effects , Mice
10.
Am J Case Rep ; 18: 589-592, 2017 May 27.
Article En | MEDLINE | ID: mdl-28550278

BACKGROUND Torsion of an intra-abdominal lipoma is rarely the cause of acute abdominal pain. Most of the previously reported cases of intra-abdominal lipoma torsion originated in the mesentery or omentum. However, an antimesenteric lipoma of the ileum with torsion has not been reported before. CASE REPORT A 67-year-old man presented to the emergency department with acute abdominal pain. Contrast-enhanced computed tomography (CECT) of the abdomen and pelvis only showed a giant fat-containing, soft-tissue, intra-abdominal tumor, suspected to be a lipoma. Laparotomy was performed, and the presence of torsion of the antimesenteric lipoma of the ileum was confirmed. Beside tumor resection, en bloc segmental resection of the ileum with end-to-end anastomosis was performed to avoid bowel stricture and obtain tumor-free margins. CONCLUSIONS CECT is the modality of choice to detect an intra-abdominal lipoma. Urgent surgical intervention should be considered if the symptoms persist and torsion cannot be excluded. If simple excision is not adequate because of poor accessibility of the tumor stalk, en bloc segmental resection with end-to-end anastomosis should be considered.


Abdominal Pain/etiology , Acute Pain/etiology , Ileal Neoplasms/pathology , Lipoma/pathology , Torsion Abnormality/pathology , Aged , Humans , Ileal Neoplasms/surgery , Lipoma/surgery , Male , Torsion Abnormality/surgery
11.
World J Gastroenterol ; 22(19): 4781-5, 2016 May 21.
Article En | MEDLINE | ID: mdl-27217710

Although primary gastrointestinal lymphoma is a rare malignancy, it can cause an intussusception in adults and can be a clinically challenging condition to manage. Intussusception could progress to life-threatening complications if left untreated or could delay chemotherapy if inappropriate surgical management is used. We report a 31-year-old man diagnosed with human immunodeficiency virus who was being treated with antiretroviral therapy. He presented with nausea, vomiting, poor appetite, and intermittent, cramping abdominal pain for over 1 wk. Abdominal computed tomography revealed a well-defined homogeneous mass in the mesenteric root region, together with a long segmental wall thickening in the ileum with ileocolic-type intussusception, which was suspected to be caused by a lymphoma. The intussusception was successfully laparoscopically reduced, and the tumor involvement of the appendix was confirmed by appendectomy with intraoperative frozen section. Systemic chemotherapy was immediately initiated after surgery without the need for bowel resection.


Appendectomy , Colonic Neoplasms/surgery , Ileal Diseases/surgery , Ileal Neoplasms/surgery , Ileocecal Valve/surgery , Intussusception/surgery , Laparoscopy , Lymphoma, Large B-Cell, Diffuse/surgery , Adult , Biopsy , Chemotherapy, Adjuvant , Colonic Neoplasms/complications , Colonic Neoplasms/diagnostic imaging , Colonoscopy , Humans , Ileal Diseases/diagnostic imaging , Ileal Diseases/etiology , Ileal Neoplasms/complications , Ileal Neoplasms/diagnostic imaging , Ileocecal Valve/diagnostic imaging , Immunohistochemistry , Intussusception/diagnostic imaging , Intussusception/etiology , Lymphoma, Large B-Cell, Diffuse/complications , Lymphoma, Large B-Cell, Diffuse/diagnostic imaging , Lymphoma, Large B-Cell, Diffuse/etiology , Male , Tomography, X-Ray Computed , Treatment Outcome
13.
Gen Comp Endocrinol ; 199: 46-55, 2014 Apr 01.
Article En | MEDLINE | ID: mdl-24486085

This study investigated the pathways involved in EGCG modulation of insulin-like growth factor (IGF)-stimulated glucose uptake in 3T3-L1 adipocytes. EGCG inhibited IGF-I and IGF-II stimulation of adipocyte glucose uptake with dose and time dependencies. EGCG at 20µM for 2h decreased IGF-I- and IGF-II-stimulated glucose uptake by 59% and 64%, respectively. Pretreatment of adipocytes with antibody against the EGCG receptor (also known as the 67-kDa laminin receptor; 67LR), prevented the effects of EGCG on IGF-increased glucose uptake, but pretreatment with normal rabbit immunoglobulin did not. This suggests that the 67LR mediates the anti-IGF effect of EGCG on adipocyte glucose uptake. Further analysis indicated EGCG, IGF-I, and IGF-II did not alter total levels of GLUT1 or GLUT4 protein. However, EGCG prevented the IGF-increased GLUT4 levels in the plasma membrane and blocked the IGF-decreased GLUT4 levels in low-density microsomes. Neither EGCG nor its combination with IGF altered GLUT1 protein levels in the plasma membrane and low-density microsomes. EGCG also suppressed the IGF-stimulated phosphorylation of IGF signaling molecules, PKCζ/λ, but not AKT and ERK1/2, proteins. This study suggests that EGCG suppresses IGF stimulation of 3T3-L1 adipocyte glucose uptake through inhibition of the GLUT4 translocation, but not through alterations of the GLUT1 pathway.


Adipocytes/metabolism , Catechin/analogs & derivatives , Glucose Transporter Type 1/metabolism , Glucose Transporter Type 4/metabolism , Glucose/metabolism , Insulin-Like Growth Factor II/metabolism , Insulin-Like Growth Factor I/metabolism , Tea/chemistry , 3T3-L1 Cells , Acetylcysteine/pharmacology , Adipocytes/drug effects , Animals , Antibodies/metabolism , Catechin/pharmacology , Cell Membrane/drug effects , Cell Membrane/metabolism , Cytoplasm/drug effects , Cytoplasm/metabolism , Mice , Phosphorylation/drug effects , Protein Transport , Receptors, Laminin/metabolism , Signal Transduction/drug effects
14.
Mol Nutr Food Res ; 56(4): 580-92, 2012 Apr.
Article En | MEDLINE | ID: mdl-22495985

SCOPE: This study investigated the pathways involved in epigallocatechin gallate (EGCG) modulation of insulin-like growth factor (IGF)-I-stimulated and IGF-II-stimulated mitogenesis in 3T3-L1 preadipocytes. METHODS AND RESULTS: We found that this process was dose and time dependent, and caused by suppression of IGF-I-stimulated and IGF-II-stimulated phosphorylation of p66Shc and mitogen-activated protein kinase (MAPK) pathway proteins, including MEK1 kinase (RAF1), extracellular signal-regulated protein kinase (ERK) kinase (MEK1), and ERK 1 and ERK 2 (ERK1/2), but not phospho-Jun-N-terminal kinase, protein kinase B, p52Shc, or p46Shc. Furthermore, EGCG inhibited the IGF-I-stimulated phosphorylation of the IGF-I receptor-beta (IGF-IR ß), the association of IGF-IR with the p66Shc protein, and the IGF-II-stimulated associations of the IGF-II receptor with G(αi-2) and p66Shc proteins, suggesting that EGCG selectively affects particular types of Shc and MAPK family members. Pretreatment with antiserum against the EGCG receptor (also known as the 67-kDa laminin receptor; 67LR), but not with an adenosine monophosphate (AMP)-activated protein kinase (AMPK) inhibitor, prevented the inhibitory actions of EGCG on IGF-I- and IGF-II-stimulated ERK1/2 phosphorylation and subsequent preadipocyte proliferation. CONCLUSION: The results of this study suggest that EGCG mediates anti-IGF-I and anti-IGF-II signals in preadipocyte mitogenesis via the 67LR but not the AMPK pathway.


Adipocytes/drug effects , Catechin/analogs & derivatives , Cell Proliferation/drug effects , Insulin-Like Growth Factor II/antagonists & inhibitors , Insulin-Like Growth Factor I/antagonists & inhibitors , Receptors, Laminin/metabolism , 3T3-L1 Cells , Adenosine Monophosphate/metabolism , Animals , Antioxidants/pharmacology , Catechin/pharmacology , Immunoprecipitation , Insulin-Like Growth Factor I/metabolism , Insulin-Like Growth Factor II/metabolism , Mice , Mitogen-Activated Protein Kinases/metabolism , Phosphorylation , Plant Extracts/pharmacology , Receptor, IGF Type 1/metabolism , Receptor, IGF Type 2/metabolism , Tea/chemistry
15.
Telemed J E Health ; 16(8): 910-5, 2010 Oct.
Article En | MEDLINE | ID: mdl-20925562

This study demonstrates transmission of 12-lead electrocardiography (ECG) in an ambulance to the cell phone of the attendant emergency medical technician and then to the hospital and to cell phones of off-site cardiologists. The emergency medical technician cell phone receives Extensible Markup Language files generated by a Phillips Extensible Markup Language ECG instrument via Wi-Fi-based wireless network and then sends them to an ECG-processing server at the hospital over the mobile telephone network. After reducing ECG noises and artifacts, the server converts files to Digital Imaging and Communications in Medicine-based ECG reports stored in Picture Archiving and Communication System. These reports are sent to the cell phones of off-site cardiologists. Consequently, on-site Emergency Department physicians and off-site cardiologists can discuss ECG reports via Picture Archiving and Communication System on their computers or cell phones to prepare for the most appropriate treatment while the patient is on the way to the hospital. In conclusion, this 12-lead ECG transmission e-technology expands the functions of a 12-lead ECG instrument and facilitates more efficient prehospital cardiac care.


Ambulances , Body Surface Potential Mapping/instrumentation , Cell Phone/instrumentation , Emergency Medical Technicians/organization & administration , Telemedicine/organization & administration , Wireless Technology/organization & administration , Body Surface Potential Mapping/methods , Cardiology/organization & administration , Emergency Service, Hospital , Humans , Taiwan
16.
Planta Med ; 76(15): 1694-8, 2010 Oct.
Article En | MEDLINE | ID: mdl-20455202

Insulin and (-)-epigallocatechin gallate (EGCG) are reported to regulate obesity and fat accumulation, respectively. This study investigated the pathways involved in EGCG modulation of insulin-stimulated glucose uptake in 3T3-L1 and C3H10T1/2 adipocytes. EGCG inhibited insulin stimulation of adipocyte glucose uptake in a dose- and time-dependent manner. The concentration of EGCG that decreased insulin-stimulated glucose uptake by 50-60% was approximately 5-10 µM for a period of 2 h. At 10 µM, EGCG and gallic acid were more effective than (-)-epicatechin, (-)-epigallocatechin, and (-)-epicatechin 3-gallate. We identified the EGCG receptor [also known as the 67-kDa laminin receptor (67LR)] in fat cells and extended the findings for this study to clarify whether EGCG-induced changes in insulin-stimulated glucose uptake in adipocytes could be mediated through the 67LR. Pretreatment of adipocytes with a 67LR antibody, but not normal rabbit immunoglobulin, prevented the effects of EGCG on insulin-increased glucose uptake. This suggests that the 67LR mediates the effect of EGCG on insulin-stimulated glucose uptake in adipocytes. Moreover, pretreatment with an AMP-activated protein kinase (AMPK) inhibitor, such as compound C, but not with a glutathione (GSH) activator, such as N-acetyl-L-cysteine (NAC), blocked the antiinsulin effect of EGCG on adipocyte glucose uptake. These data suggest that EGCG exerts its anti-insulin action on adipocyte glucose uptake via the AMPK, but not the GSH, pathway. The results of this study possibly support that EGCG mediates fat content.


AMP-Activated Protein Kinases/metabolism , Catechin/analogs & derivatives , Glucose/metabolism , Insulin/pharmacology , Receptors, Laminin/physiology , Tea/chemistry , Animals , Catechin/chemistry , Catechin/isolation & purification , Catechin/pharmacology , Mice , Mice, Inbred C3H , NIH 3T3 Cells
17.
Planta Med ; 76(7): 694-6, 2010 May.
Article En | MEDLINE | ID: mdl-19937554

Green tea catechins, especially (-)-epigallocatechin-3-gallate (EGCG), are known to regulate obesity and fat accumulation. We performed a kinetic analysis in a cell-free system to determine the mode of inhibition of glycerol-3-phosphate dehydrogenase (GPDH; EC 1.1.1.8) by EGCG. GPDH catalyzes the beta-nicotinamide adenine dinucleotide (NADH)-dependent reduction of dihydroxyacetone phosphate (DHAP) to yield glycerol-3-phosphate, which serves as one of the major precursors of triacylglycerols. We found that EGCG dose-dependently inhibited GPDH activity at a concentration of approximately 20 muM for 50 % inhibition. The IC (50) values of other green tea catechins, such as (-)-epicatechin, (-)-epicatechin-3-gallate, and (-)-epigallocatechin, were all above 100 microM. This suggests a catechin type-dependent effect. Based on double-reciprocal plots of the kinetic data, EGCG was a noncompetitive inhibitor of the GPDH substrates, NADH and DHAP, with respective inhibition constants (Ki) of 18 and 31 microM. Results of this study possibly support previous studies that EGCG mediates fat content.


Catechin/analogs & derivatives , Glycerol-3-Phosphate Dehydrogenase (NAD+)/antagonists & inhibitors , Catechin/pharmacology , Drug Evaluation, Preclinical , Triglycerides/biosynthesis
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