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1.
J Microbiol Immunol Infect ; 57(3): 498-508, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38632021

ABSTRACT

BACKGROUND: Tuberculosis (TB) remains prevalent worldwide, and anti-TB drugs are associated with drug-induced liver injury (DILI). Statins have pleiotropic effects which may decrease inflammation and achieve immunomodulation. However, few studies have investigated the pleiotropic effects of statins on the risk of DILI. The purpose of this study was to investigate whether statins prevent anti-tuberculosis DILI among active TB patients on standard anti-TB drug therapy. METHODS: We conducted a hospital-based retrospective cohort study using claims data from the Integrated Medical Database of National Taiwan University Hospital (NTUH-iMD). Patients with a positive TB culture were included. The use of statins was defined as a daily equivalent dose >0.5 mg of pitavastatin. Deterioration in liver function was evaluated according to elevated liver enzyme levels. The primary and secondary endpoints were the DILI and the severe DILI. The prognostic value of statins was evaluated by Kaplan-Meier analysis, and Cox proportional hazards models. RESULTS: A total of 1312 patients with a diagnosis of TB and receiving anti-TB treatment were included. During the study period, 193 patients had the DILI and 140 patients had the severe DILI. Kaplan-Meier analysis showed a significant difference between the usual statin users and controls in the DILI. In multivariable Cox proportional hazards analysis, statins showed a protective effect against the primary and secondary endpoints. In addition, the protective effect of statins showed a dose-response relationship against the DILI. CONCLUSION: Statin treatment had a protective effect against the risk of anti-TB DILI with a positive dose-response relationship.


Subject(s)
Antitubercular Agents , Chemical and Drug Induced Liver Injury , Hydroxymethylglutaryl-CoA Reductase Inhibitors , Tuberculosis , Humans , Male , Female , Retrospective Studies , Antitubercular Agents/adverse effects , Antitubercular Agents/therapeutic use , Middle Aged , Taiwan/epidemiology , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Hydroxymethylglutaryl-CoA Reductase Inhibitors/adverse effects , Tuberculosis/drug therapy , Adult , Aged , Proportional Hazards Models , Risk Factors , Kaplan-Meier Estimate
2.
J Formos Med Assoc ; 121(12): 2512-2519, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35701304

ABSTRACT

BACKGROUND: Although blood test is a routine in major burns, its relationship with burn size and intensive care unit length of stay (ICULOS) remains undetermined. We investigated the feasibility of using these tests as a reference for definite diagnosis of major burn size, burn size >20% of the total body surface area (TBSA), and their relationships with ICULOS. METHODS: Data of routine laboratory blood tests within 24 h after burns (n = 73) were collected retrospectively. Correlation tests and regression analyses were performed. RESULTS: Burns ≥20 TBSA had higher incidences of leucocytosis, hypoalbuminaemia, elevated haemoglobin (Hb), and elevated haematocrit (Hct). Burn size was correlated negatively with albumin but positively with Hb, Hct, and white blood cell (WBC) count. For each unit increase in blood urea nitrogen (BUN)/creatinine (Cr), there was an increase of 1.2 days of ICULOS in females, while in males, there was a 6.7 day increase for every unit increase in Hb and a 3.1 day increase for each unit increase in BUN. A female model including Hb and WBC was derived, discriminating burns ≥20 TBSA with sensitivity and specificity 0.94 and 1.0 respectively, and area under the receiver operating characteristic curve (AUROC) 0.96 (95% CI 0.91-1.00). The male model had sensitivity 0.96, specificity 1.0, and AUROC 0.96 (95% CI 0.89-1.00). CONCLUSION: Admission Hb and WBC could be used as a reference for definite diagnosis of major burn size, especially in borderline cases. BUN/Cr in females, and Hb and BUN in males, were related to ICULOS.


Subject(s)
Burns , Male , Female , Humans , Length of Stay , Retrospective Studies , Burns/diagnosis , Body Surface Area , Intensive Care Units
3.
Am J Obstet Gynecol ; 225(3): 292.e1-292.e17, 2021 09.
Article in English | MEDLINE | ID: mdl-33744177

ABSTRACT

BACKGROUND: Ultrasound has demonstrated a high accuracy in the prenatal diagnosis of placenta accreta spectrum. However, it is not known whether ultrasound findings can pinpoint the depths of villous invasion, recommend surgical strategies, and predict clinical outcomes. OBJECTIVE: We described an ultrasound descriptor for the placenta accreta spectrum and investigated whether it can predict the severity of villous invasion and clinical outcomes. STUDY DESIGN: The patients with placenta accreta spectrum in this retrospective cross-sectional study were diagnosed and managed in our hospital from 2002 to 2017. The placenta, with overlying myometrium and bladder, was mapped with color Doppler sonography while the patient's bladder was full. A "rail sign" was defined as 2 parallel neovascularizations depicted by color Doppler sonography over the uterovesical junction and bladder mucosa, with interconnecting bridging vessels perpendicular to both. The patients received serial ultrasound examinations and surgery at our hospital. An unpaired t test and Pearson chi-square test compared the pathology subtypes, surgical strategies, and clinical outcomes in patients with or without a rail sign. RESULTS: We enrolled 133 consecutive cases of placenta accreta spectrum confirmed either by surgical inspection or pathology examination. Patients with a rail sign had a significantly higher risk of an abnormally invasive placenta (placenta increta or placenta percreta) than those patients without a rail sign (83.3% [60 of 72] vs 27.9% [17 of 61]; odds ratio, 12.94; P<.001). In addition, patients with a rail sign had a higher probability of perioperative approaches, including preoperative vascular control (58.3% [42 of 72] vs 21.3% [13 of 61]; odds ratio, 5.17; P<.001) and uterine artery embolization (34.7% [25 of 72] vs 11.5% [7 of 61]; odds ratio, 4.1; P=.0002]. Furthermore, patients with a rail sign carried a higher risk of adverse clinical outcomes than patients without a rail sign, such as blood transfusion (80.6% [58 of 72] vs 36.1% [22 of 61]; odds ratio, 7.34; P<.001], admission to the intensive care unit (33.3% [24 of 72] vs 16.4% [10 of 61]; odds ratio, 2.55; P=.026), hysterectomy (75% [54 of 72] vs 24.6% [15 of 61]; odds ratio, 9.2; P<.001), and bladder invasion (16.7% [12 of 72] vs 4.9% [3 of 61]; odds ratio, 3.86; P=.033). Notably, the negative predictive value of bladder invasion was 95.1%, indicating a high confidence to reject bladder invasion while the rail sign was negative. When the rail sign was used as a screening test, the positive likelihood ratio of predicting deep villous invasion was 3.64 and correlated with an increased probability of 20% to 25%. Patients with a rail sign also had a greater blood loss (2944±2748 mL vs 1530±1895 mL; P<.001) and a longer hospital stay (11.9±10.9 days vs 8.6±7.1 days; P=.036) than patients without a rail sign. CONCLUSION: A "rail sign" depicted by color Doppler sonography correlates with deeper villous invasion, additional perioperative approaches, and more adverse outcomes.


Subject(s)
Neovascularization, Pathologic/diagnostic imaging , Placenta Accreta/diagnostic imaging , Placenta/blood supply , Placenta/diagnostic imaging , Ultrasonography, Doppler, Color , Adult , Blood Transfusion/statistics & numerical data , Cross-Sectional Studies , Female , Humans , Hysterectomy/statistics & numerical data , Intensive Care Units , Mucous Membrane/diagnostic imaging , Patient Admission/statistics & numerical data , Pregnancy , Retrospective Studies , Urinary Bladder/diagnostic imaging , Uterine Artery Embolization/statistics & numerical data
4.
J Clin Periodontol ; 47(9): 1108-1120, 2020 09.
Article in English | MEDLINE | ID: mdl-32592595

ABSTRACT

AIMS: We aimed to update a previous network meta-analysis comparing the efficacy of periodontal regenerative therapies on the treatment of infrabony lesions. MATERIALS AND METHODS: Seven clinical trials were added after literature research for studies published between January 2011 and September 2019. We conducted network meta-analysis (NMA) to compare the effects of guided tissue regeneration (GTR), enamel matrix derivatives (EMD) and their combination therapies on probing pocket depth (PPD) reduction and clinical attachment level (CAL) gain. Sequential network meta-analysis (SNMA) was also used to control the type-I error rate due to multiple testing. RESULTS: A total of 60 studies were included. For both PPD reduction and CAL gain, the flap operation (FO) was the least effective treatment. Although the differences between periodontal regenerative therapies were small, GTR attained the greatest reduction in PPD, and EMD with bone graft the greatest CAL gain compared to other therapies. SNMA used stricter efficacy criteria, yielding slightly different results from NMA. CONCLUSIONS: EMD, GTR, and their combined therapies were more effective than flap operation, although the differences between regenerative therapies remain small in this updated study. SNMA reduces the risk of false-positive findings, thereby providing more robust evidence on the superiority of treatments.


Subject(s)
Alveolar Bone Loss , Dental Enamel Proteins , Alveolar Bone Loss/surgery , Bone Transplantation , Dental Enamel Proteins/therapeutic use , Follow-Up Studies , Guided Tissue Regeneration, Periodontal , Humans , Network Meta-Analysis , Periodontal Attachment Loss/surgery , Treatment Outcome
5.
Molecules ; 22(12)2017 Dec 01.
Article in English | MEDLINE | ID: mdl-29194373

ABSTRACT

(1) Background: In China and South Asia, Alstonia scholaris (Apocynaceae) is an important medicinal plant that has been historically used in traditional ethnopharmacy to treat infectious diseases. Although various pharmacological activities have been reported, the anti-lung cancer components of A. scholaris have not yet been identified. The objective of this study is to evaluate the active components of the leaf extract of A. scholaris, and assess the anti-proliferation effects of isolated compounds against non-small-cell lung carcinoma cells; (2) Methods: NMR was used to identify the chemical constitutes isolated from the leaf extract of A. scholaris. The anti-proliferative activity of compounds against non-small-cell lung carcinoma cells was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay; (3) Results: Eight triterpenoids and five sterols were isolated from the hexane portion of A. scholaris, and structurally identified as: (1) ursolic acid, (2) oleanolic acid, (3) betulinic acid, (4) betulin, (5) 2ß,3ß,28-lup-20(29)-ene-triol, (6) lupeol, (7) ß-amyrin, (8) α-amyrin, (9) poriferasterol, (10) epicampesterol, (11) ß-sitosterol, (12) 6ß-hydroxy-4-stigmasten-3-one, and (13) ergosta-7,22-diene-3ß,5α,6ß-triol. Compound 5 was isolated from a plant source for the first time. In addition, compounds 9, 10, 12, and 13 were also isolated from A. scholaris for the first time. Ursolic acid, betulinic acid, betulin, and 2ß,3ß,28-lup-20(29)-ene-triol showed anti-proliferative activity against NSCLC, with IC50 of 39.8, 40.1, 240.5 and 172.6 µM, respectively.; (4) Conclusion: These findings reflect that pentacyclic triterpenoids are the anti-lung cancer chemicals in A. scholaris. The ability of ursolic acid, betulinic acid, betulin, and 2ß,3ß,28-lup-20(29)-ene-triol to inhibit the proliferative activity of NSCLC can constitute a valuable group of therapeutic agents in the future.


Subject(s)
Alstonia/chemistry , Antineoplastic Agents/pharmacology , Phytosterols/pharmacology , Sterols/pharmacology , Triterpenes/pharmacology , A549 Cells , Antineoplastic Agents/chemistry , Carcinoma, Non-Small-Cell Lung , Cell Proliferation/drug effects , Humans , Lung Neoplasms , Pentacyclic Triterpenes , Phytosterols/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plant Leaves/chemistry , Sterols/chemistry , Tetrazolium Salts/chemistry , Thiazoles/chemistry , Triterpenes/chemistry , Betulinic Acid , Ursolic Acid
6.
Molecules ; 21(7)2016 Jul 07.
Article in English | MEDLINE | ID: mdl-27399657

ABSTRACT

(1) BACKGROUND: Several triterpenoids were found to act synergistically with classes of antibiotic, indicating that plant-derived chemicals have potential to be used as therapeutics to enhance the activity of antibiotics against multidrug-resistant pathogens. However, the mode of action of triterpenoids against bacterial pathogens remains unclear. The objective of this study is to evaluate the interaction between ursolic acid against methicillin-resistant Staphylococcus aureus (MRSA); (2) METHODS: The ability of ursolic acid to damage mammalian and bacterial membranes was examined. The proteomic response of methicillin-resistant S. aureus in ursolic acid treatment was investigated using two-dimensional (2D) proteomic analysis; (3) RESULTS: Ursolic acid caused the loss of staphylococcal membrane integrity without hemolytic activity. The comparison of the protein pattern of ursolic acid-treated and normal MRSA cells revealed that ursolic acid affected a variety of proteins involved in the translation process with translational accuracy, ribonuclease and chaperon subunits, glycolysis and oxidative responses; (4) CONCLUSION: The mode of action of ursolic acid appears to be the influence on the integrity of the bacterial membrane initially, followed by inhibition of protein synthesis and the metabolic pathway. These findings reflect that the pleiotropic effects of ursolic acid against MRSA make it a promising antibacterial agent in pharmaceutical research.


Subject(s)
Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Methicillin-Resistant Staphylococcus aureus/drug effects , Triterpenes/chemistry , Triterpenes/pharmacology , Animals , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Cell Membrane/drug effects , Methicillin-Resistant Staphylococcus aureus/physiology , Microbial Sensitivity Tests , Models, Biological , Molecular Structure , Protein Biosynthesis/drug effects , Protein Interaction Mapping , Protein Interaction Maps , Proteomics/methods , Sheep , Ursolic Acid
7.
J Agric Food Chem ; 63(48): 10407-17, 2015 Dec 09.
Article in English | MEDLINE | ID: mdl-26567590

ABSTRACT

In our previous study, ursolic acid present in the leaves of Rhododendron formosanum was found to possess antineoplastic activity. We further isolated and unveiled a natural product, cinnamtannin D1 (CNT D1), an A-type procyanidin trimer in R. formosanum also exhibiting anticancer efficacy that induced G1 arrest (83.26 ± 3.11% for 175 µM CNT D1 vs 69.28 ± 1.15% for control, p < 0.01) and autophagy in non-small-cell lung carcinoma (NSCLC) cells. We found that CNT D1-mediated autophagy was via the noncanonical pathway, being beclin-1-independent but Atg5 (autophagy-related genes 5)-dependent. Inhibition of autophagy with a specific inhibitor enhanced cell death, suggesting a cytoprotective function for autophagy in CNT D1-treated NSCLC cells. Moreover, CNT D1 inhibited the Akt/mammalian target of the rapamycin (mTOR) pathway and activated the extracellular signal-regulated kinases 1/2 (ERK1/2) pathway, resulting in induction of autophagy.


Subject(s)
Anthocyanins/administration & dosage , Antineoplastic Agents/administration & dosage , Autophagy/drug effects , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , MAP Kinase Signaling System/drug effects , Plant Extracts/administration & dosage , Rhododendron/chemistry , Apoptosis/drug effects , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/physiopathology , Cell Line, Tumor , Humans , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Lung Neoplasms/physiopathology , Male , Middle Aged , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects , TOR Serine-Threonine Kinases/genetics , TOR Serine-Threonine Kinases/metabolism
8.
Molecules ; 20(7): 12787-803, 2015 Jul 15.
Article in English | MEDLINE | ID: mdl-26184152

ABSTRACT

Rhododendron formosanum is an endemic species distributed in the central mountains of Taiwan. In this study, the biological activities of major procyanidins isolated from the leaf extract of R. formosanum were investigated. Four compounds, including two procyanidin dimers, procyanidin A1 (1) and B3 (2), and two procyanidin trimmers, procyanidin C4 (4) and cinnamtannin D1 (5), were isolated and identified on the basis of spectroscopic data. The structure of a new procyanidin dimer, rhodonidin A (3), was elucidated by 2D-NMR, CD spectrum and MS. The procyanidin trimmers and rhodonidin A are reported for the first time in Ericaceae. The biological activities of these procyanidins were evaluated using anti-bacterial and anti-oxidative assays. Only the new compound 3 demonstrated strong anti-bacterial activity against Staphylococcus aureus at an MIC value of 4 µg/mL. All compounds showed pronounced antioxidant activities and the activities are enhanced as the amount of OH groups in procyanidins increased. In conclusion, the pleiotropic effects of procyanidins isolated from the leaves of R. formosanum can be a source of promising compounds for the development of future pharmacological applications.


Subject(s)
Anti-Bacterial Agents/chemistry , Antioxidants/chemistry , Plant Leaves/chemistry , Proanthocyanidins/chemistry , Rhododendron/chemistry , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Antioxidants/isolation & purification , Antioxidants/pharmacology , Biphenyl Compounds/antagonists & inhibitors , Biphenyl Compounds/chemistry , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Molecular Structure , Oxidation-Reduction , Picrates/antagonists & inhibitors , Picrates/chemistry , Plant Extracts/chemistry , Proanthocyanidins/isolation & purification , Proanthocyanidins/pharmacology , Staphylococcus aureus/drug effects , Staphylococcus aureus/growth & development , Structure-Activity Relationship , Taiwan
9.
J Agric Food Chem ; 62(4): 875-84, 2014 Jan 29.
Article in English | MEDLINE | ID: mdl-24447325

ABSTRACT

The aim of the present study was to investigate whether Rhododendron formosanum Hemsl. (Ericaceae), an endemic species in Taiwan, exhibits antineoplastic potential against non-small-cell lung carcinoma (NSCLC). R. formosanum was successively extracted with methanol and then separated into dichloromethane (RFL-DCM), ethyl acetate (RFL-EA), n-butanol (RFL-BuOH), and water (RFL-H2O) fractions. Among these extracts, RFL-EA exhibited the most effective antineoplastic effect. This study also demonstrated that fractions 2 and 3 from the RFL-EA extract (RFL-EA-2, RFL-EA-3) possessed the strongest antineoplastic potential against NSCLC cells. The major phytochemical constituents of RFL-EA-2 and RFL-EA-3 were ursolic acid, oleanolic acid, and betulinic acid. This study indicated that ursolic acid demonstrated the most efficient antineoplastic effects on NSCLC cells. Ursolic acid inhibited growth of NSCLC cells in a dose- and time-dependent manner and stimulated apoptosis. Apoptosis was substantiated by activation of caspase-3 and -9, and a decrease in Bcl-2 and an elevation of the Bax were also observed following ursolic acid treatment. Ursolic acid activated AMP-activated protein kinase (AMPK) and then inhibited the mammalian target of rapamycin (mTOR), which controls protein synthesis and cell growth. Moreover, ursolic acid decreased the expression and/or activity of lipogenic enzymes, such as acetyl-CoA carboxylase (ACC) and fatty acid synthase (FASN) via AMPK activation. Collectively, these data provide insight into the chemical constituents and anticancer activity of R. formosanum against NSCLC cells, which are worthy of continued study.


Subject(s)
Antineoplastic Agents, Phytogenic/administration & dosage , Carcinoma, Non-Small-Cell Lung/pathology , Plant Extracts/administration & dosage , Rhododendron/chemistry , AMP-Activated Protein Kinases/metabolism , Acetates , Apoptosis/drug effects , Carcinoma, Non-Small-Cell Lung/drug therapy , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Taiwan , Triterpenes/administration & dosage , Ursolic Acid
10.
J Agric Food Chem ; 60(46): 11533-41, 2012 Nov 21.
Article in English | MEDLINE | ID: mdl-23113763

ABSTRACT

Lung cancer is the most commonly diagnosed cancer and the leading cause of cancer deaths globally. Due to the lack of successful chemopreventive agents for lung cancer, there is an emerging need to evaluate new and effective agents for lung cancer prevention. Pterostilbene, a naturally occurring analogue of resveratrol, has been reported to be an effective chemopreventive agent against many cancers. The aim of this study is to investigate the chemopreventive effects of pterostilbene in urethane-induced murine lung tumors. Pretreatment with pterostilbene at 50 or 250 mg/kg significantly reduced tumor multiplicity by 26 and 49%, respectively. Pterostilbene also significantly inhibited tumor volume by 25 and 34% and decreased the tumor burden per mouse by 45 and 63%, respectively. The mechanisms by which pterostilbene suppresses lung tumorigenesis have been investigated in lung tissues and homogenates. The results indicate that the pterostilbene-mediated chemopreventive effects in vivo were a result of the inhibition of epidermal growth factor receptor (EGFR) and its downstream pathways, leading to retarded cell cycle progression, and of the induction of apoptosis and autophagy during urethane-induced lung tumorigenesis.


Subject(s)
Apoptosis/drug effects , Autophagy/drug effects , Lung Neoplasms/prevention & control , Protective Agents/administration & dosage , Stilbenes/administration & dosage , Animals , Cell Division/drug effects , Cell Line, Tumor , Chemoprevention , Down-Regulation/drug effects , ErbB Receptors/genetics , ErbB Receptors/metabolism , Humans , Lung/drug effects , Lung/metabolism , Lung/physiopathology , Lung Neoplasms/chemically induced , Lung Neoplasms/metabolism , Lung Neoplasms/physiopathology , Male , Mice , Signal Transduction/drug effects , Urethane/adverse effects
11.
Mol Nutr Food Res ; 53(9): 1156-65, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19662644

ABSTRACT

In the previous studies, (-)-epigallocatechin-3-gallate (EGCG) has been shown to have anticarcinogenic effects via modulation in protein expression of p53. Using p53 positive Hep G2 and p53 negative Hep 3B cells, we found that treatment of EGCG resulted in dose-dependent inhibition of cellular proliferation, which suggests that the interaction of EGCG with p53 may not fully explain its inhibitory effect on proliferation. Caloric restriction (CR) reduces the incidence and progression of spontaneous and induced tumors in laboratory rodents. EGCG has multiple beneficial activities similar to those associated with CR. One key enzyme thought to be activated during CR is AMP-activated kinase (AMPK), a sensor of cellular energy levels. Here, we showed that EGCG activated AMPK in both p53 positive and negative human hepatoma cells. The activation of AMPK suppressed downstream substrates, such as mammalian target of rapamycin (mTOR) and eukaryotic initiation factor 4E-binding protein-1 (4E-BP1) and a general decrease in mRNA translation. Moreover, EGCG activated AMPK decreases the activity and/or expression of lipogenic enzymes, such as fatty acid synthase (FASN) and acetyl-CoA carboxylase (ACC). Interestingly, the decision between apoptosis and growth arrest following AMPK activation is greatly influenced by p53 status. In p53 positive Hep G2 cells, EGCG blocked the progression of cell cycle at G1 phase by inducing p53 expression and further up-regulating p21 expression. However, EGCG inducted apoptosis in p53 negative Hep 3B cells. Based on these results, we have demonstrated that EGCG has a potential to be a chemoprevention and anti-lipogenesis agent for human hepatoma cells.


Subject(s)
AMP-Activated Protein Kinases/metabolism , Anticarcinogenic Agents/pharmacology , Carcinoma, Hepatocellular/drug therapy , Catechin/analogs & derivatives , Cell Cycle/drug effects , Lipogenesis/drug effects , Liver Neoplasms/drug therapy , Protein Biosynthesis/drug effects , Tumor Suppressor Protein p53/analysis , Acetyl-CoA Carboxylase/genetics , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Catechin/pharmacology , Cell Line, Tumor , Fatty Acid Synthases/genetics , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Protein Kinases/physiology , TOR Serine-Threonine Kinases , Tumor Suppressor Protein p53/physiology
12.
J Agric Food Chem ; 57(12): 5257-64, 2009 Jun 24.
Article in English | MEDLINE | ID: mdl-19459711

ABSTRACT

In the present study, we successively extracted the pu-erh raw tea with methanol (PR-1), chloroform (PR-2), ethyl acetate (PR-3), n-butanol (PR-4), and water (PR-5). Among these extracts, PR-3 extract contained ingredients with the most effective hypolipidemic potential and was further purified by column chromatography. Moreover, chronic administration of PR-3 provoked a significant reduction in levels of serum triglyceride and low-density lipoprotein (LDL) in rats. Our study demonstrated that fraction 5 from the PR-3 extract (PR-3-5s) showed a hypolipidemic effect in human hepatoma HepG2 cells. PR-3-5s decreased the expression of fatty acid synthase (FASN) and inhibited the activity of acetyl-coenzyme A carboxylase (ACC) by stimulating AMP-activated protein kinase (AMPK) through the LKB1 pathway. Moreover, PR-3-5s blocked the progression of the cell cycle at the G1 phase by inducing p53 expression and in turn upregulating p21 expression.


Subject(s)
AMP-Activated Protein Kinases/metabolism , Cardiovascular Diseases/metabolism , Cell Proliferation/drug effects , Lipogenesis/drug effects , Plant Extracts/pharmacology , Tea/chemistry , AMP-Activated Protein Kinases/genetics , Animals , Cardiovascular Diseases/drug therapy , Cardiovascular Diseases/enzymology , Cardiovascular Diseases/physiopathology , Cell Cycle/drug effects , Cell Line , Enzyme Activation/drug effects , Humans , Male , Models, Animal , Plant Extracts/administration & dosage , Plant Extracts/chemistry , Rats , Rats, Sprague-Dawley
13.
FEBS Lett ; 581(30): 5735-42, 2007 Dec 22.
Article in English | MEDLINE | ID: mdl-18022396

ABSTRACT

Fatty acid synthase (FAS) expression is markedly elevated in HER2-overexpressing breast cancer cells. In this study, diosgenin, a plant-derived steroid, was found to be effective in suppressing FAS expression in HER2-overexpressing breast cancer cells. Diosgenin preferentially inhibited proliferation and induced apoptosis in HER2-overexpressing cancer cells. Furthermore, diosgenin inhibited the phosphorylation of Akt and mTOR, and enhanced phosphorylation of JNK. The use of pharmacological inhibitors revealed that the modulation of Akt, mTOR and JNK phosphorylation was required for diosgenin-induced FAS suppression. Finally, we showed that diosgenin could enhance paclitaxel-induced cytotoxicity in HER2-overexpressing cancer cells. These results suggested that diosgenin has the potential to advance as chemopreventive or chemotherapeutic agent for cancers that overexpress HER2.


Subject(s)
Breast Neoplasms/enzymology , Diosgenin/pharmacology , JNK Mitogen-Activated Protein Kinases/metabolism , Protein Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Receptor, ErbB-2/metabolism , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Diosgenin/chemistry , Down-Regulation/drug effects , Drug Screening Assays, Antitumor , Fatty Acid Synthases/biosynthesis , Fatty Acid Synthases/genetics , Humans , Palmitic Acid/pharmacology , Phosphoproteins/metabolism , Phosphorylation/drug effects , Protein Kinase Inhibitors/pharmacology , Receptor, ErbB-2/genetics , Solanaceous Alkaloids/chemistry , Solanaceous Alkaloids/pharmacology , TOR Serine-Threonine Kinases , Tomatine/analogs & derivatives , Tomatine/chemistry , Tomatine/pharmacology , Up-Regulation/drug effects
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