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1.
Water Res ; 251: 121150, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38246079

RESUMO

Dissolved organic nitrogen (DON) is a pivotal component of total dissolved nitrogen pools, serving as a crucial nitrogen source for phytoplankton. This study investigated the impact of nitrogen-to-phosphorus (N/P) ratios and different DON components (hydrophilic vs hydrophobic DON) on diatom-dinoflagellate succession through field culture experiments. Results showed that dinoflagellates have a competitive advantage under high N/P ratios and phosphorus limitation, regardless of DON or DIN treatments. Hydrophilic DON exhibits greater bioavailability than hydrophobic DON (40.6% vs. 21.7 %), resulting in increased algal biomass and diatoms dominance in the community. Additionally, DON was categorized into labile and refractory components (LDON and RDON) based on bioavailability. LDON primarily consists of protein-like components that can be readily consumed by algae, whereas RDON is primarily composed of humic-like components that are less accessible to algae. Diatoms and dinoflagellates exhibited differential responses to LDON and RDON, with diatoms thriving in high LDON environments, while dinoflagellates gained a competitive advantage when RDON was the predominant nitrogen source. Furthermore, a significant negative correlation was observed between bioavailable nitrogen concentration (BAN: DIN + LDON) and the ratio of dinoflagellates to diatoms (p<0.05). In conclusion, our study highlights the role of LDON in promoting diatom dominance, whereas environments dominated by RDON foster dinoflagellate success. These findings enhance our comprehension of diatom-dinoflagellate succession dynamics.


Assuntos
Diatomáceas , Dinoflagellida , Matéria Orgânica Dissolvida , Nitrogênio/análise , Fósforo
2.
Chin J Nat Med ; 21(2): 146-153, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36871982

RESUMO

Four unreported monoterpene indole alkaloids, tabernaecorymines B-E (1-4), together with twenty-one known indole alkaloids (5-25) were obtained from the stem bark of Tabernaemontana corymbosa. Their structures and absolute configurations were elucidated by extensive spectroscopy, quantum chemical calculations, DP4+ probability analyses and Mo2(OAc)4-induced electronic circular dichroism experiment. The antibacterial and antifungal activities of these compounds were evaluated and some of them showed significant activity against Staphylococcus aureus,Bacillus subtilis, Streptococcus dysgalactiae and Candida albicans.


Assuntos
Anti-Infecciosos , Tabernaemontana , Antifúngicos , Antibacterianos , Alcaloides Indólicos
3.
Mar Environ Res ; 183: 105841, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36512865

RESUMO

Prorocentrum donghaiense blooms occur annually in the East China Sea coastal waters, degrading ecosystem functions and impeding economic development. Dissolved organic nitrogen and phosphorus (DON and DOP) are the main components in the marine nutrient pools and are closely related to harmful algal blooms. From April to June 2019, a survey was conducted along the East China Sea coast (Sansha and Lianjiang counties) to investigate the relationship between dissolved organic nutrients and P. donghaiense bloom. Our findings showed that dinoflagellates dominated the phytoplankton community, and dissolved organic nutrients were the major factors influencing community structure during the P. donghaiense bloom. Redundancy analysis indicated that P. donghaiense abundance was primarily affected by DON in the Sansha area while it was primarily affected by DON and DOP in the Lianjiang area. Correlation analysis also confirmed a strong positive correlation between dissolved organic nutrients and P. donghaiense abundance both in the Sansha and Lianjiang coastal areas (p < 0.001). Furthermore, a culture experiment was carried out during the bloom to further investigate the effect of dissolved organic nutrients on the phytoplankton community structure. After 10 days of culture, dinoflagellates' relative abundance decreased from 97.1% to 28.2% in the inorganic treatment, whereas dinoflagellates continued to dominate the phytoplankton community in the organic treatment (76.9%). As a result, we propose that dissolved organic nutrients are responsible for the P. donghaiense bloom outbreak and promote the phytoplankton community shift from diatoms to dinoflagellates.


Assuntos
Dinoflagellida , Ecossistema , Proliferação Nociva de Algas , Fitoplâncton , China , Fósforo , Nutrientes , Nitrogênio
4.
J Periodontal Res ; 55(3): 354-362, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31960448

RESUMO

OBJECTIVES: This trial aimed to evaluate the efficacy and safety of vitamin D supplementation on the residual moderate and deep pockets following nonsurgical periodontal therapy. BACKGROUND: Vitamin D supplementation has potential effects on periodontitis, but current evidence remains inconclusive. METHODS: After 3 months of nonsurgical periodontal treatment, 360 patients with moderate or severe periodontitis were randomly assigned to 2000 international unit (IU)/d vitamin D3, 1000 IU/d vitamin D3, or placebo. Clinical periodontal examinations, including probing depth (PD), bleeding index (BI), plaque index (PLI), attachment loss (AL), and alveolar crest height (ACH), were performed at baseline and after 3 months of intervention. RESULTS: There was a slight but significant decrease in AL and PD in both vitamin D groups compared with placebo group for moderate and deep pockets. About 2000 IU/d vitamin D3 group, 1000 IU/d vitamin D3 group, and placebo group all decreased the AL for both moderate pockets (-0.4 mm vs -0.4 mm vs -0.3 mm) and deep pockets (-1.1 mm vs -1.1 mm vs -1.0 mm) (all P < .05). Similarly, PD was also decreased in these three groups for both moderate pockets and deep pockets (all P < .05). In addition, vitamin D supplementation was well tolerated, and no adverse events were reported. CONCLUSIONS: Although statistically significant differences were observed in favor to vitamin D supplementation, the magnitude of effect size tended to be modest with limited clinical relevance and the long-term efficacy and safety warrant further investigation.


Assuntos
Assistência Odontológica , Suplementos Nutricionais , Periodontite/terapia , Vitamina D/administração & dosagem , Vitaminas/administração & dosagem , Colecalciferol , Índice de Placa Dentária , Método Duplo-Cego , Humanos
5.
J Ethnopharmacol ; 217: 140-151, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29458146

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Experience-based herbal medicine as a complementary to modern western medicine has triggered an array of studies in quest of novel anticancer drugs. Scutellaria barbata D. Don (SB) is commonly used to treat different types of cancers, but its molecular mechanism of action is not clearly understood. In this study, we attempted to elucidate the mode of action of a traditional Chinese medicine prescription with a total of 14 components, named Lian-Jia-San-Jie-Fang (LJSJF, in Chinese), where SB works as the "principle" against non-small cell lung cancer (NSCLC) cells. MATERIALS AND METHODS: Four different NSCLC cell lines (A549, H460, H1650, and H1975) were used. Cytotoxicity, in vitro tumorigenicity, gene expression, and protein expression were analyzed by MTT assay, soft agar assay, real-time PCR, and Western blots, respectively. RESULTS: Among the 14 components in LJSJF, SB was the only one to possess cytotoxic effects at its pharmacologically relevant doses. Additionally, we observed synergistically dose-dependent cytotoxic effects of SB in combination with other LJSJF components. After SB or LJSJF treatment, significant reductions in colony number and/or size were observed in A549 and H460; a notable dose-dependent decrease in EGFR was observed in A549, H460, and H1650; significant downregulation in EGFR and its downstream signaling targets mTOR and p38MAPK were also observed in A549 and H460; and p53 and p21 were significantly increased while survivin, cyclin D1, and MDM2 were significantly decreased in A549. Additionally, p53, p21, and Mettl7b were decreased, but p73 was increased in H460. Neither EGFR nor p53 was changed in H1975. Therefore, SB or LJSJF may induce cytotoxic effects by regulating multiple and/or distinct apoptotic pathways in different NSCLC cells. CONCLUSION: LJSJF exerts more pronounced cytotoxic effects against NSCLC cells than SB does by synergistically regulating the underlining molecular mechanisms including EGFR and/or p53 signaling pathways.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Extratos Vegetais/farmacologia , Scutellaria , Células A549 , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Receptores ErbB/efeitos dos fármacos , Receptores ErbB/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Fitoterapia , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Scutellaria/química , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
6.
Biofactors ; 43(4): 529-539, 2017 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-28247504

RESUMO

Our previous study found curcumin and vitamin E to have protective effects against benzo[a]pyrene (BaP) exposure in human normal lung epithelial BEAS-2B cells. The first objective of this study was to determine whether epigallocatechin-3-gallate (EGCG) elicited the same response. Co-treatment with 5 µM BaP and 20 µM EGCG in BEAS-2B promoted a significant reduction in cell viability and greater G2/M cell cycle arrest, induction of ROS, and reductions in BaP-induced CYP1A1/CYP1B1/COMT, EGFR, p-Akt (Ser473), p-p53 (Thr55), and survivin mRNA/protein expression, as well as an increase in p-p53 (Ser15). Based on these findings, the second objective was to extend the investigation by developing a novel BaP-transformed BEAS-2B cell line, BEAS-2BBaP , to examine the effects of EGCG when co-administered with gefitinib, an EGFR tyrosine kinase inhibitor. Cell colony formation assay demonstrated in vitro tumorigenic potential of BEAS-2BBaP , which had an overexpression of EGFR. Viability testing revealed gefitinib co-treatment with EGCG resulted in more cell death compared with gefitinib alone. Co-treated cells had greater reductions in gefitinib-induced CYP1A1/CYB1B1, EGFR, cyclin D1, p-Akt (Ser473), and survivin mRNA/protein expression, as well as an increase in p-p53 (Ser15). Therefore, EGCG was found to promote greater cytotoxicity to BEAS-2B co-treated with BaP and BEAS-2BBaP upon gefitinib co-treatment through regulating metabolism enzymes and signaling pathways involving EGFR and p53. These findings suggest that EGCG did not act as a protective compound in BEAS-2B after acute BaP exposure, but has the potential to be a useful adjuvant chemotherapeutic compound when coupled with gefitinib for chemosensitization. © 2017 BioFactors, 43(4):529-539, 2017.


Assuntos
Benzo(a)pireno/toxicidade , Catequina/análogos & derivados , Western Blotting , Catequina/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citocromo P-450 CYP1A1/metabolismo , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Citometria de Fluxo , Gefitinibe , Humanos , Quinazolinas/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
7.
J Nutr Biochem ; 40: 1-13, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27723473

RESUMO

Pesticides, smoke, mycotoxins, polychlorinated biphenyls (PCBs), and arsenic are the most common environmental toxins and toxicants to humans. These toxins and toxicants may impact on human health at the molecular (DNA, RNA, or protein), organelle (mitochondria, lysosome, or membranes), cellular (growth inhibition or cell death), tissue, organ, and systemic levels. Formation of reactive radicals, lipid peroxidation, inflammation, genotoxicity, hepatotoxicity, embryotoxicity, neurological alterations, apoptosis, and carcinogenic events are some of the mechanisms mediating the toxic effects of the environmental toxins and toxicants. Green tea, the nonoxidized and nonfermented form of tea that contains several polyphenols, including green tea catechins, exhibits protective effects against these environmental toxins and toxicants in preclinical studies and to a much-limited extent, in clinical trials. The protective effects are collectively mediated by antioxidant, antiinflammatory, antimutagenic, hepatoprotective and neuroprotective, and anticarcinogenic activities. In addition, green tea modulates signaling pathway including NF-κB and ERK pathways, preserves mitochondrial membrane potential, inhibits caspase-3 activity, down-regulates proapoptotic proteins, and induces the phase II detoxifying pathway. The bioavailability and metabolism of green tea and its protective effects against environmental insults induced by pesticides, smoke, mycotoxins, PCBs, and arsenic are reviewed in this paper. Future studies with emphasis on clinical trials should identify biomarkers of green tea intake, examine the mechanisms of action of green tea polyphenols, and investigate potential interactions of green tea with other toxicant-modulating dietary factors.


Assuntos
Catequina/farmacocinética , Exposição Ambiental/efeitos adversos , Micotoxinas/toxicidade , Praguicidas/toxicidade , Chá , Arsênio/toxicidade , Disponibilidade Biológica , Catequina/farmacologia , Humanos , Neoplasias/prevenção & controle , Bifenilos Policlorados/toxicidade , Chá/química
8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 47(5): 805-809, 2016 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-28598103

RESUMO

OBJECTIVES: To assess the safety and tolerance of healthy volunteers to as tragalosides injection (AGI), and to determine a safe dose range for phase II clinical trial. METHODS: A total of 62 healthy volunteers participated in this study, with 26 being given a single AGI of 100 mL, 200 mL, 300 mL, 400 mL, 500 mL, or 600 mL and 36 subjects being given 500 mL, 400 mL, 200 mL or 300 mL of AGI once a day for 7 d. Discomfortsymptoms, vital signs and safety problems were recorded 3 d and 7 d after the administration of AGI. The results were analyzed. RESULTS: Of the 62 participants, 40 adverse events (AEs) were reported by 31 participants, which included 23 mild adverse reactions (ADRs) and 4 moderate ADRs. Nine AEs were reported by 9 participants with single AGI, including 7 ADRs. Fourteen AEs were reported by 10 participants with 500 mL and 400 mL multiple AGI, including 12 ADRs occurred in 9 participants.Seventeen AEs were reported by 12 participants with 300 mL and 300 mL multiple AGI, including 3 mild ADRs. The main ADRs included abnormal liver function [slightly elevated glutamic pyruvic transaminase (ALT), glutamic oxaloacetic transaminase (AST),and serum total bilirubin (TBil)], low blood potassium, increased urine red blood cell count, rash, and phlebitis. CONCLUSIONS: The maximum tolerance is 600 mL for single-dose treatment, and 400 mL for multiple-dose (7 d). The dose guidance given in this study should be examined its effects and safety in patients with coronary heart disease in phase II clinical trial.


Assuntos
Doença das Coronárias/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Saponinas/administração & dosagem , Triterpenos/administração & dosagem , Medicamentos de Ervas Chinesas/efeitos adversos , Voluntários Saudáveis , Humanos , Fígado/efeitos dos fármacos , Saponinas/efeitos adversos , Triterpenos/efeitos adversos
9.
Chin J Integr Med ; 20(10): 729-36, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25098260

RESUMO

OBJECTIVE: To determine the effects of Ginkgo biloba extract (EGB) on major periodontal pathogens in subgingival plaque. METHODS: Sixty patients with moderate to severe periodontitis were selected and randomly assigned to 3 groups: EGB group, a positive (periocline) and a negative control groups. Subgingival plaque samples were collected before treatment and 1 week, 2 months and 4 months after treatment. The detection rates of 4 major periodontal pathogens-Treponema denticola (Td), Tannerella forsythus (Tf), Prevotella intermedia (Pi), and Porphyromonas gingivalis (Pg)-were detected by polymerase chain reaction (PCR). Clinical indicators were examined before treatment, 3 and 6 months after treatment. RESULTS: EGB significantly decreased the detection rate of all the 4 pathogens 1 week after treatment, and then gradually increased at 2 and 4 months. EGB's inhibition effect was better than or comparable to periocline, except for Pg in short-term. The difference of plaque index (PLI) and bleeding index (BI) was not statistically significant among the groups, while for probing depth (PD) and attachment loss (AL), the difference was statistically significant between the EGB group and negative control group at 3 and 6 months after treatment. CONCLUSION: EGB significantly inhibited major periodontal pathogens and can be used as an adjuvant for periodontitis treatment.


Assuntos
Adjuvantes Farmacêuticos/farmacologia , Bactérias/efeitos dos fármacos , Placa Dentária/tratamento farmacológico , Placa Dentária/microbiologia , Ginkgo biloba/química , Periodonto/microbiologia , Extratos Vegetais/farmacologia , Adjuvantes Farmacêuticos/uso terapêutico , Bactérias/isolamento & purificação , Seguimentos , Humanos , Periodonto/efeitos dos fármacos , Periodonto/patologia , Extratos Vegetais/uso terapêutico , Reação em Cadeia da Polimerase , Resultado do Tratamento
10.
Nutr Res ; 33(8): 668-76, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23890357

RESUMO

This study investigates the effects of a restricted diet (RD) on body composition and musculoskeletal health along with endocrines and molecular mechanism in established mature obese rats. Twenty female rats were fed with a high-fat diet (HFD) ad libitum for 4 months and then assigned to either HFD or RD group for another 4 months. Another 10 rats were on a low-fat diet for 8 months. Outcome measures included body composition, bone mineral density, microarchitecrure, and strength; serum leptin, adiponectin, insulin-like growth factor I, and liver glutathione peroxidase activity; and protein expression and spleen tumor necrosis factor α messenger RNA expression. We hypothesized that mature obese rats on a 35% energy restriction diet for 4 months would improve body composition but degrade microstructural and mechanical properties of long bones, and such changes in musculoskeletal integrity are related to the modulation of obesity-related endocrines and proinflammation. Relative to HFD, RD benefited body composition (decreased body weight and %fat mass and increased %fat-free mass); decreased insulin-like growth factor I and leptin; elevated adiponectin, glutathione peroxidase activity and protein expression and tumor necrosis factor α messenger RNA expression; and suppressed bone formation and increased bone resorption, resulting in decreased trabecular and cortical bone volume, bone mineral density, and bone strength. Relative to low-fat diet, RD had a similar effect on body composition and serum markers but increased bone turnover rate and decreased bone mineral density and strength. Our data suggest that long-term RD has a negative impact on bone remodeling in obese female rats, probably through modification of endocrines and elevation of proinflammation.


Assuntos
Composição Corporal , Densidade Óssea , Reabsorção Óssea/etiologia , Osso e Ossos , Restrição Calórica/efeitos adversos , Obesidade , Osteogênese/fisiologia , Adiponectina/sangue , Animais , Biomarcadores/sangue , Osso e Ossos/metabolismo , Osso e Ossos/fisiopatologia , Dieta com Restrição de Gorduras , Dieta Hiperlipídica , Feminino , Glutationa Peroxidase/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Leptina/sangue , Fígado/metabolismo , Obesidade/complicações , Obesidade/dietoterapia , Obesidade/metabolismo , Proteínas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Baço/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Redução de Peso/fisiologia
11.
J Liposome Res ; 23(3): 187-96, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23600473

RESUMO

The chemopreventive actions exerted by green tea are thought to be due to its major polyphenol, (-)-epigallocatechin-3-gallate (EGCG). However, the low level of stability and bioavailability in the body makes administering EGCG at chemopreventive doses unrealistic. We synthesized EGCG encapsulated chitosan-coated nanoliposomes (CSLIPO-EGCG), and observed their antiproliferative and proapoptotic effect in MCF7 breast cancer cells. CSLIPO-EGCG significantly enhanced EGCG stability, improved sustained release, increased intracellular EGCG content in MCF7 cells, induced apoptosis of MCF7 cells, and inhibited MCF7 cell proliferation compared to native EGCG and void CSLIPO. The CSLIPO-EGCG retained its antiproliferative and proapoptotic effectiveness at 10 µM or lower, at which native EGCG does not have any beneficial effects. This study portends a potential breakthrough in the prevention or even treatment of breast cancer by using biocompatible and biodegradable CSLIPO-EGCG with enhanced chemopreventive efficacy and minimized immunogenicity and side-effects.


Assuntos
Anticarcinógenos/uso terapêutico , Catequina/análogos & derivados , Proliferação de Células/efeitos dos fármacos , Nanoconjugados/administração & dosagem , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Catequina/administração & dosagem , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Feminino , Humanos , Lipossomos , Células MCF-7
12.
Nutr Res ; 32(6): 448-57, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22749181

RESUMO

This study investigates the effects of green tea polyphenols (GTPs) on body composition and bone properties along with mechanisms in obese female rats. Thirty-six 3-month-old Sprague Dawley female rats were fed either a low-fat (LF) or a high-fat (HF) diet for 4 months. Animals in the LF diet group continued on an LF diet for additional 4 months, whereas those in the HF diet group were divided into 2 groups: with GTP (0.5%) or without in drinking water, in addition to an HF diet for another 4 months. Body composition, femur bone mass and strength, serum endocrine and proinflammatory cytokines, and liver glutathione peroxidase (GPX) protein expression were determined. We hypothesized that supplementation of GTP in drinking water would benefit body composition, enhance bone quality, and suppress obesity-related endocrines in HF diet-induced obese female rats and that such changes are related to an elevation of antioxidant capacity and a reduction of proinflammatory cytokine production. After 8 months, compared with the LF diet, the HF diet increased percentage of fat mass and serum insulin-like growth factor I and leptin levels; reduced percentage of fat-free mass, bone strength, and GPX protein expression; but had no effect on bone mineral density and serum adiponectin levels in the rats. Green tea polyphenol supplementation increased percentage of fat-free mass, bone mineral density and strength, and GPX protein expression and decreased percentage of fat mass, serum insulin-like growth factor I, leptin, adiponectin, and proinflammatory cytokines in the obese rats. This study shows that GTP supplementation benefited body composition and bone properties in obese rats possibly through enhancing antioxidant capacity and suppressing inflammation.


Assuntos
Antioxidantes/farmacologia , Composição Corporal/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Suplementos Nutricionais , Obesidade/fisiopatologia , Polifenóis/farmacologia , Chá/química , Adiponectina/sangue , Tecido Adiposo/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Citocinas/sangue , Dieta Hiperlipídica/efeitos adversos , Água Potável/administração & dosagem , Ingestão de Energia , Feminino , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Leptina/sangue , Músculo Esquelético/efeitos dos fármacos , Obesidade/induzido quimicamente , Obesidade/tratamento farmacológico , Ratos , Ratos Sprague-Dawley
13.
PLoS One ; 7(6): e38332, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22715380

RESUMO

Beneficial effects of green tea polyphenols (GTP) against obesity have been reported, however, the mechanism of this protection is not clear. Therefore, the objective of this study was to identify GTP-targeted genes in obesity using the high-fat-diet-induced obese rat model. A total of three groups (n = 12/group) of Sprague Dawley (SD) female rats were tested, including the control group (rats fed with low-fat diet), the HF group (rats fed with high-fat diet), and the HF+GTP group (rats fed with high-fat diet and GTP in drinking water). The HF group increased body weight as compared to the control group. Supplementation of GTP in the drinking water in the HF+GTP group reduced body weight as compared to the HF group. RNA from liver samples was extracted for gene expression analysis. A total of eighty-four genes related to obesity were analyzed using PCR array. Compared to the rats in the control group, the rats in the HF group had the expression levels of 12 genes with significant changes, including 3 orexigenic genes (Agrp, Ghrl, and Nr3c1); 7 anorectic genes (Apoa4, Cntf, Ghr, IL-1ß, Ins1, Lepr, and Sort); and 2 genes that relate to energy expenditure (Adcyap1r1 and Adrb1). Intriguingly, the HF+GTP group restored the expression levels of these genes in the high-fat-induced obese rats. The protein expression levels of IL-1ß and IL-6 in the serum samples from the control, HF, and HF+GTP groups confirmed the results of gene expression. Furthermore, the protein expression levels of superoxide dismutase-1 (SOD1) and catechol-O-methyltransferase (COMT) also showed GTP-regulated protective changes in this obese rat model. Collectively, this study revealed the beneficial effects of GTP on body weight via regulating obesity-related genes, anti-inflammation, anti-oxidant capacity, and estrogen-related actions in high-fat-induced obese rats.


Assuntos
Peso Corporal/efeitos dos fármacos , Camellia sinensis/química , Regulação da Expressão Gênica/efeitos dos fármacos , Obesidade/metabolismo , Polifenóis/farmacologia , Chá/química , Animais , Gorduras na Dieta/efeitos adversos , Feminino , Obesidade/induzido quimicamente , Polifenóis/química , Ratos , Ratos Sprague-Dawley
14.
Nutrition ; 27(6): 681-6, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20708377

RESUMO

OBJECTIVE: Our recent study demonstrated the protective action of green tea polyphenols (GTPs) against bone loss in ovariectomized (OVX) rats through their antioxidant capacities to scavenge reactive oxygen species. The objective of the present study was to evaluate the alterations of liver protein profiles in estrogen-deficient middle-aged rats after GTP treatment by a gel-based proteomic approach. This may lead to understanding the mechanisms of GTPs in promoting bone health. METHODS: Liver samples were obtained from 14-mo-old female OVX rats treated with no GTPs (OVX) or 0.5% (w/v) GTPs (OVX + GTP) in drinking water for 16 wk (n = 10/group). Two-dimensional difference gel electrophoresis combined with mass spectrometry was used to compare the liver protein profiles of pooled samples from the OVX and OVX + GTP groups. Liver proteins were labeled in duplicate by reversing the fluorescent dyes. RESULTS: Approximately 800 protein spots were detected. The expression levels of superoxide dismutase-1 and adenosine triphosphate synthase were 2.0-fold and 1.5-fold higher in the OVX + GTP group versus the OVX group, respectively, whereas the expression level of catechol-O-methyltransferase was 1.5-fold lower in the OVX + GTP group versus the OVX group. The changes of superoxide dismutase-1 and catechol-O-methyltransferase in individual liver samples were confirmed by western blots. CONCLUSION: Our data provide further evidence for the antioxidant role of GTPs by increasing superoxide dismutase-1 and adenosine triphosphate synthase and the estrogen-associated effect of GTPs by decreasing catechol-O-methyltransferase.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Suplementos Nutricionais , Flavonoides/uso terapêutico , Fígado/metabolismo , Osteoporose Pós-Menopausa/prevenção & controle , Fenóis/uso terapêutico , Proteômica/métodos , Chá/química , Animais , Antioxidantes/uso terapêutico , Conservadores da Densidade Óssea/química , Camellia sinensis/química , Catecol O-Metiltransferase/metabolismo , Suplementos Nutricionais/análise , Feminino , Flavonoides/análise , Humanos , Isoenzimas/metabolismo , Osteoporose Pós-Menopausa/metabolismo , Ovariectomia , Fragmentos de Peptídeos/metabolismo , Fenóis/análise , Folhas de Planta/química , Polifenóis , Distribuição Aleatória , Ratos , Ratos Endogâmicos F344 , Superóxido Dismutase/metabolismo , Eletroforese em Gel Diferencial Bidimensional
15.
Curr Drug Discov Technol ; 7(1): 32-6, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20156141

RESUMO

Traditional Chinese/herbal medicine (TCM) is now commonly used by cancer patients of Asian ethnicity to supplement or replace prescribed treatments. The overall survival rate for lung cancer has not improved significantly in the past several decades; it remains the leading cause of cancer death. Much more attention has been paid by clinicians and researchers to the possible use of compound Chinese medicine (CCM) as effective anti-lung cancer medicines. In this review, we briefly summarize the clinical and experimental status of numerous CCMs recently developed primarily in China for the treatment of lung cancer, including formulations, treatment effectiveness, and molecular mechanisms. By presenting this information, our goal is to possibly open up new future avenues for the practice of lung cancer treatment.


Assuntos
Química Farmacêutica/métodos , Medicamentos de Ervas Chinesas/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Medicina Tradicional Chinesa/métodos , Metástase Neoplásica/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Humanos
16.
Carcinogenesis ; 29(2): 411-7, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18192689

RESUMO

To evaluate the efficacy of green tea polyphenols (GTPs) in modulating aflatoxin B(1) (AFB(1)) biomarkers, a total of 352 serum samples and 352 urine samples collected from a 3 month chemoprevention trial with 500 mg GTPs, 1000 mg GTPs and a placebo were measured for AFB(1)-albumin adducts (AFB-AA), aflatoxin M(1) (AFM(1)) and aflatoxin B(1)-mercapturic acid (AFB-NAC). Levels of AFB-AA at baseline were comparable for all three dose groups (P = 0.506). No significant differences were observed in AFB-AA levels in the placebo group over the 3 month period (P = 0.252). However, a significant reduction in AFB-AA levels was observed in the 500 mg group (P = 0.002). A marginally significant reduction in AFB-AA levels was also found in the 1000 mg group over the 3 month intervention period (P = 0.051). An analysis using a mixed-effects model indicated that the reduction in AFB-AA levels over time was dose and time dependent (dose-time interaction P = 0.049). There were no significant differences in median AFM(1) levels among the three study groups at the baseline (P = 0.832), 1 month (P = 0.188) and 3 months (P = 0.132) of the GTP intervention; however, reduction of 42 and 43% in median AFM(1) levels, as compared with the placebo, were found in 500 mg (P = 0.096) and 1000 mg (P = 0.072) groups at 3 months of the intervention. Significant elevations in median AFB-NAC levels and the ratio of AFB-NAC:AFM(1) were found in both 500 and 1000 mg groups compared with the placebo group at both 1 month (P < 0.001) and 3 months (P < 0.001) of GTPs intervention. These results demonstrate that GTPs effectively modulate AFB(1) metabolism and metabolic activation.


Assuntos
Aflatoxinas/sangue , Aflatoxinas/farmacologia , Aflatoxinas/urina , Anticarcinógenos/farmacologia , Biomarcadores , Flavonoides/química , Fenóis/química , Adulto , Quimioprevenção , Feminino , Flavonoides/farmacologia , Humanos , Masculino , Modelos Biológicos , Fenóis/farmacologia , Placebos , Polifenóis , Radioimunoensaio/métodos , Chá , Fatores de Tempo
17.
Food Chem Toxicol ; 46(1): 232-40, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17888558

RESUMO

Health benefits of green tea polyphenols (GTPs) have been reported in many animal models, but human studies are inconclusive. This is partly due to a lack of biomarkers representing green tea consumption. In this study, GTP components and metabolites were analyzed in plasma and urine samples collected from a phase II intervention trial carried out in 124 healthy adults who received 500- or 1000-mg GTPs or placebo for 3 months. A significant dose-dependent elevation was found for (-)-epicatechin-3-gallate (ECG) (p<0.001, trend test) and (-)-epigallocatechin-3-gallate (EGCG) (p<0.05, trend test) concentrations in plasma at both 1-month and 3-months after intervention with GTPs. No significant increase of (-)-epicatechin (EC) or (-)-epigallocatechin (EGC) was observed in plasma after GTP intervention. A mixed-effects model indicated significant effects of dose (EGCG) and dose by time interaction (ECG), but not for EC and EGC. Analysis of phase 2 metabolic conjugates revealed a predominance of free GTPs in plasma, up to 85% for EGCG, while a majority of GTPs in urine were sulfated and glucuronidated conjugates (up to 100% for EC and 89% for EGC). These results suggest that plasma ECG and EGCG concentrations are reliable biomarkers for green tea consumption at the population level.


Assuntos
Biomarcadores/análise , Flavonoides/farmacologia , Fenóis/farmacologia , Chá/química , Adulto , Catequina/análogos & derivados , Catequina/análise , Relação Dose-Resposta a Droga , Feminino , Flavonoides/química , Guanosina Trifosfato/metabolismo , Guanosina Trifosfato/urina , Humanos , Masculino , Pessoa de Meia-Idade , Fenóis/química , Polifenóis , Reprodutibilidade dos Testes
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