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1.
Phytomedicine ; 129: 155614, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38692078

RESUMO

BACKGROUND: Cellular senescence is an emerging hallmark of cancers, primarily fuels cancer progression by expressing senescence-associated secretory phenotype (SASP). Caveolin-1 (CAV1) is a key mediator of cell senescence. Previous studies from our group have evidenced that the expression of CAV1 is downregulated by Celastrol (CeT). PURPOSE: To investigate the impact of CeT on cellular senescence and its subsequent influence on post-senescence-driven invasion, migration, and stemness of clear cell renal cell carcinoma (ccRCC). STUDY DESIGN AND METHODS: The expression levels of CAV1, canonical senescence markers, and markers associated with epithelial-mesenchymal transition (EMT) and stemness in clinical samples were assessed through Pearson correlation analysis. Senescent cell models were induced using DOX, and their impact on migration, invasion, and stemness was evaluated. The effects of CeT treatment on senescent cells and their pro-tumorigenic effects were examined. Subsequently, the underlying mechanism of CeT were explored using lentivirus transfection and CRISPR/Cas9 technology to silence CAV1. RESULTS: In human ccRCC clinical samples, the expression of the canonical senescence markers p53, p21, and p16 are associated with ccRCC progression. Senescent cells facilitated migration, invasion, and enhanced stemness in both ccRCC cells and ccRCC tumor-bearing mice. As expected, CeT treatment reduced senescence markers (p16, p53, p21, SA-ß-gal) and SASP factors (IL6, IL8, CXCL12), alleviating cell cycle arrest. However, it did not restore the proliferation of senescent cells. Additionally, CeT suppressed senescence-driven migration, invasion, and stemness. Further investigations into the underlying mechanism demonstrated that CAV1 is a critical mediator of cell senescence and represents a potential target for CeT to attenuate cellular senescence. CONCLUSIONS: This study presents a pioneering investigation into the intricate interplay between cellular senescence and ccRCC progression. We unveil a novel mechanism of CeT to mitigate cellular senescence by downregulating CAV1, thereby inhibiting the migration, invasion and stemness of ccRCC driven by senescent cells. These findings provide valuable insights into the underlying mechanisms of CeT and its potential as a targeted therapeutic approach for alleviating the aggressive phenotypes associated with senescent cells in ccRCC.


Assuntos
Carcinoma de Células Renais , Caveolina 1 , Senescência Celular , Transição Epitelial-Mesenquimal , Triterpenos Pentacíclicos , Caveolina 1/metabolismo , Senescência Celular/efeitos dos fármacos , Humanos , Triterpenos Pentacíclicos/farmacologia , Carcinoma de Células Renais/tratamento farmacológico , Linhagem Celular Tumoral , Animais , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Triterpenos/farmacologia , Movimento Celular/efeitos dos fármacos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Camundongos
2.
Curr Pharm Des ; 30(16): 1265-1278, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38584553

RESUMO

BACKGROUND: Targeting immunogenic cell death (ICD) is considered a promising therapeutic strategy for cancer. However, the commonly identified ICD inducers promote the expression of programmed cell death ligand 1 (PD-L1) in tumor cells, thus aiding them to evade the recognition and killing by the immune system. Therefore, the finding of novel ICD inducers to avoid enhanced PD-L1 expression is of vital significance for cancer therapy. Celastrol (CeT), a triterpene isolated from Tripterygium wilfordii Hook. F induces various forms of cell death to exert anti-cancer effects, which may make celastrol an attractive candidate as an inducer of ICD. METHODS: In the present study, bioinformatics analysis was combined with experimental validation to explore the underlying mechanism by which CeT induces ICD and regulates PD-L1 expression in clear cell renal cell carcinoma (ccRCC). RESULTS: The results showed that EGFR, IKBKB, PRKCQ and MAPK1 were the crucial targets for CeT-induced ICD, and only MAPK1 was an independent prognostic factor for the overall survival (OS) of ccRCC patients. In addition, CeT triggered autophagy and up-regulated the expressions of HMGB1 and CRT to induce ICD in 786-O cells in vitro. Importantly, CeT can down-regulate PD-L1 expression through activating autophagy. At the molecular level, CeT suppressed PD-L1 via the inhibition of MAPK1 expression. Immunologically, the core target of celastrol, MAPK1, was tightly correlated with CD8+ T cells and CD4+ T cells in ccRCC. CONCLUSION: These findings indicate that CeT not only induces ICD but also suppresses PD-L1 by down-regulating MAPK1 expression, which will provide an attractive strategy for ccRCC immunotherapy.


Assuntos
Antígeno B7-H1 , Carcinoma de Células Renais , Regulação para Baixo , Neoplasias Renais , Triterpenos Pentacíclicos , Triterpenos Pentacíclicos/farmacologia , Humanos , Antígeno B7-H1/metabolismo , Antígeno B7-H1/antagonistas & inibidores , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/metabolismo , Regulação para Baixo/efeitos dos fármacos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Neoplasias Renais/imunologia , Antineoplásicos/farmacologia , Triterpenos/farmacologia , Morte Celular Imunogênica/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais
3.
J Am Chem Soc ; 146(1): 289-297, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38135454

RESUMO

Copper (Cu), with the advantage of producing a deep reduction product, is a unique catalyst for the electrochemical reduction of CO2 (CO2RR). Designing a Cu-based catalyst to trigger CO2RR to a multicarbon product and understanding the accurate structure-activity relationship for elucidating reaction mechanisms still remain a challenge. Herein, we demonstrate a rational design of a core-shell structured silica-copper catalyst (p-Cu@m-SiO2) through Cu-Si direct bonding for efficient and selective CO2RR. The Cu-Si interface fulfills the inversion in CO2RR product selectivity. The product ratio of C2H4/CH4 changes from 0.6 to 14.4 after silica modification, and the current density reaches a high of up to 450 mA cm-2. The kinetic isotopic effect, in situ attenuated total reflection Fourier-transform infrared spectra, and density functional theory were applied to elucidate the reaction mechanism. The SiO2 shell stabilizes the *H intermediate by forming Si-O-H and inhibits the hydrogen evolution reaction effectively. Moreover, the direct-bonded Cu-Si interface makes bare Cu sites with larger charge density. Such bare Cu sites and Si-O-H sites stabilized the *CHO and activated the *CO, promoting the coupling of *CHO and *CO intermediates to form C2H4. This work provides a promising strategy for designing Cu-based catalysts with high C2H4 catalytic activity.

4.
Biomed Pharmacother ; 164: 114981, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37285754

RESUMO

Lipid metabolism disorders are pivotal in the development of various lipid-related diseases, such as obesity, atherosclerosis, non-alcoholic fatty liver disease, type 2 diabetes, and cancer. Celastrol, a bioactive compound extracted from the Chinese herb Tripterygium wilfordii Hook F, has recently demonstrated potent lipid-regulating abilities and promising therapeutic effects for lipid-related diseases. There is substantial evidence indicating that celastrol can ameliorate lipid metabolism disorders by regulating lipid profiles and related metabolic processes, including lipid synthesis, catabolism, absorption, transport, and peroxidation. Even wild-type mice show augmented lipid metabolism after treatment with celastrol. This review aims to provide an overview of recent advancements in the lipid-regulating properties of celastrol, as well as to elucidate its underlying molecular mechanisms. Besides, potential strategies for targeted drug delivery and combination therapy are proposed to enhance the lipid-regulating effects of celastrol and avoid the limitations of its clinical application.


Assuntos
Diabetes Mellitus Tipo 2 , Triterpenos Pentacíclicos , Triterpenos , Animais , Camundongos , Metabolismo dos Lipídeos , Lipídeos , Triterpenos/farmacologia , Triterpenos/uso terapêutico , Triterpenos/metabolismo
5.
Stem Cell Res Ther ; 13(1): 432, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36042526

RESUMO

Cancer stem cells (CSCs) are a subpopulation of cancer cells with stem cell properties that sustain cancers, which may be responsible for cancer metastasis or recurrence. Lipid rafts are cholesterol- and sphingolipid-enriched microdomains in the plasma membrane that mediate various intracellular signaling. The occurrence and progression of cancer are closely related to lipid rafts. Emerging evidence indicates that lipid raft levels are significantly enriched in CSCs compared to cancer cells and that most CSC markers such as CD24, CD44, and CD133 are located in lipid rafts. Furthermore, lipid rafts play an essential role in CSCs, specifically in CSC self-renewal, epithelial-mesenchymal transition, drug resistance, and CSC niche. Therefore, lipid rafts are critical regulatory platforms for CSCs and promising therapeutic targets for cancer therapy.


Assuntos
Neoplasias , Células-Tronco Neoplásicas , Transição Epitelial-Mesenquimal , Humanos , Microdomínios da Membrana/metabolismo , Neoplasias/metabolismo , Neoplasias/terapia , Células-Tronco Neoplásicas/metabolismo , Transdução de Sinais
6.
Front Pharmacol ; 13: 831657, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35924044

RESUMO

The high level of serum cholesterol caused by the excessive absorption of cholesterol can lead to hypercholesteremia, thus promoting the occurrence and development of cancer. Ezetimibe is a drug that reduces cholesterol absorption and has been widely used for the treatment of patients with high circulating cholesterol levels for many years. Mechanistically, ezetimibe works by binding to NPC1L1, which is a key mediator of cholesterol absorption. Accumulating data from preclinical models have shown that ezetimibe alone could inhibit the development and progression of cancer through a variety of mechanisms, including anti-angiogenesis, stem cell suppression, anti-inflammation, immune enhancement and anti-proliferation. In the past decade, there has been heated discussion on whether ezetimibe combined with statins will increase the risk of cancer. At present, more and more evidence shows that ezetimibe does not increase the risk of cancers, which supports the role of ezetimibe in anti-cancer. In this review, we discussed the latest progress in the anti-cancer properties of ezetimibe and elucidated its underlying molecular mechanisms. Finally, we highlighted the potential of ezetimibe as a therapeutic agent in future cancer treatment and prevention.

7.
Cell Oncol (Dordr) ; 45(5): 709-728, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35864437

RESUMO

BACKGROUND: Disturbance of cholesterol homeostasis is considered as one of the manifestations of cancer. Cholesterol plays an essential role in the pleiotropic functions of cancer cells, including mediating membrane trafficking, intracellular signal transduction, and production of hormones and steroids. As a single transmembrane receptor, the low-density lipoprotein receptor (LDLR) can participate in intracellular cholesterol uptake and regulate cholesterol homeostasis. It has recently been found that LDLR is aberrantly expressed in a broad range of cancers, including colon cancer, prostate cancer, lung cancer, breast cancer and liver cancer. LDLR has also been found to be involved in various signaling pathways, such as the MAPK, NF-κB and PI3K/Akt signaling pathways, which affect cancer cells and their surrounding microenvironment. Moreover, LDLR may serve as an independent prognostic factor for lung cancer, breast cancer and pancreatic cancer, and is closely related to the survival of cancer patients. However, the role of LDLR in some cancers, such as prostate cancer, remains controversial. This may be due to the lack of normal feedback regulation of LDLR expression in cancer cells and the severe imbalance between LDLR-mediated cholesterol uptake and de novo biosynthesis of cholesterol. CONCLUSIONS: The imbalance of cholesterol homeostasis caused by abnormal LDLR expression provides new therapeutic opportunities for cancer. LDLR interferes with the occurrence and development of cancer by modulating cholesterol homeostasis and may become a novel target for the development of anti-cancer drugs. Herein, we systematically review the contribution of LDLR to cancer progression, especially its dysregulation and underlying mechanism in various malignancies. Besides, potential targeting and immunotherapeutic options are proposed.


Assuntos
Colesterol , Neoplasias , Humanos , Colesterol/metabolismo , Homeostase , Hormônios , Lipoproteínas LDL/metabolismo , NF-kappa B , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Microambiente Tumoral , Neoplasias/metabolismo
8.
Front Oncol ; 12: 803473, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35251975

RESUMO

Lipid metabolism disorder is related to an increased risk of tumorigenesis and is involved in the rapid growth of cancer cells as well as the formation of metastatic lesions. Epidemiological studies have demonstrated that low-density lipoprotein (LDL) and oxidized low-density lipoprotein (ox-LDL) are closely associated with breast cancer, colorectal cancer, pancreatic cancer, and other malignancies, suggesting that LDL and ox-LDL play important roles during the occurrence and development of cancers. LDL can deliver cholesterol into cancer cells after binding to LDL receptor (LDLR). Activation of PI3K/Akt/mTOR signaling pathway induces transcription of the sterol regulatory element-binding proteins (SREBPs), which subsequently promotes cholesterol uptake and synthesis to meet the demand of cancer cells. Ox-LDL binds to the lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) and cluster of differentiation 36 (CD36) to induce mutations, resulting in inflammation, cell proliferation, and metastasis of cancer. Classic lipid-lowering drugs, statins, have been shown to reduce LDL levels in certain types of cancer. As LDL and ox-LDL play complicated roles in cancers, the potential therapeutic effect of targeting lipid metabolism in cancer therapy warrants more investigation.

9.
Fitoterapia ; 128: 50-56, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29689329

RESUMO

Carpesium humile Winkl is an endemic Chinese species and no previous phytochemical studies have been reported for this species. Two new germacranolides (1 and 2) and a new phytane diterpene (5), together with five known compounds (two sesquiterpenoids and three diterpenoids), were isolated from the aerial parts of C. humile. Their structures were elucidated on the basis of extensive spectroscopic analysis. The conformations and absolute configurations of 1 and 2 were established by combinative analysis of NMR, CD exciton chirality, and X-ray crystallography data. Four germacranolides (1-4) showed strong cytotoxic activities, with broad spectrum activities against six human cancer (HepG2, HeLa, HL60, SGC7901, Lewis, and MDA231) cell lines in vitro using MTT assay, with IC50 values from 3.09 to 7.71 µg/mL. Diterpenes (5, 6, and 8) also displayed good cytotoxic activities for selected cancer cell lines, with IC50 values in the range 5.46-8.08 µg/mL.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Asteraceae/química , Diterpenos/isolamento & purificação , Sesquiterpenos de Germacrano/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Diterpenos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Componentes Aéreos da Planta/química , Sesquiterpenos de Germacrano/farmacologia
10.
Fitoterapia ; 124: 113-119, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29066296

RESUMO

Extracts of the aerial parts of Scorzonera divaricata afforded sulfoscorzonin D (1) and sulfoscorzonin E (2), two novel pyrrolidine inner salt alkaloids with a sulfated guaiane sesquiterpene lactone nucleus, along with 22 known compounds. Especially, sulfoscorzonin D containing a unusual monoterpene moiety is very rare. The structures of new compounds were established using spectroscopic analysis including one- and two-dimensional NMR and HRESIMS. The cytotoxicities of compounds 1-4 and 10 against three tumor cell lines (K562, Hela, and HepG2) were evaluated using the MTT assay. Compounds 2 and 10 exhibited moderate cytotoxic activity. The biological properties of 1-3, 5-8, 10-14, and 16-24, were screened against nine different gram-positive and gram-negative bacteria. Compounds 1, 5-8, 10, and 18, showed potent antibacterial activities. CHEMICAL COMPOUNDS STUDIED IN THIS ARTICLE: Glucozaluzanin C (PubChem CID: 442320); 1ß,4α-dihydroxy-5α,6ß,7α,11ßH-eudermn-12; 6-olide (CID: 11119093); oleanolic acid (CID: 10494); lup-20(29)-ene-3ß,28-diol (CID: 72326); (22E)-5α,8α-epidioxyergosta-6,22-dien-3ß-ol (CID: 5469431); ergosta-3ß,5α, 6ß-trialcohol (CID: 44558918); stigma-5-en-3-O-ß-glucoside (CID: 5742590); vomifoliol (CID: 12444927); trans-caffeic acid (CID: 689043); trans-p-hydroxy coumaric acid (CID: 637542); 4-hydroxy-3-methoxyphenyl ferulate (CID: 11500646); 7,3',4'-trihydroxyflavonol (CID: 5281614); tricin (ID: 5281702); luteolin (CID: 5280445); diosmetin (CID: 5281612); 5,7-dihydroxy-8-methoxyflavone (CID: 5281703); 5,7-dihydroxy-6-methoxyflavone (CID: 5320315); methyl-3,4-dihydroxy benzoate (CID: 287064); m-hydroxy benzoic acid (CID: 7420); 7-hydroxy-coumarin (CID: 5281426); and scopoletin (CID: 5280460).


Assuntos
Alcaloides/isolamento & purificação , Componentes Aéreos da Planta/química , Scorzonera/química , Sesquiterpenos de Guaiano/isolamento & purificação , Antibacterianos/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Estrutura Molecular
11.
Fitoterapia ; 116: 24-33, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27984167

RESUMO

Six eremophilane-type (parasenolide A-F) and an eudesmane-type (parasenin) sesquiterpenoids, along with eight known sesquiterpenes, were isolated from the whole plants of Parasenecio roborowskii. The structures and absolute configurations of new compounds were elucidated using extensive spectroscopic analysis, including HRESIMS, 1D and 2D NMR experiments, the CD exciton chirality methods, and single-crystal X-ray crystallography. All isolated compounds were evaluated for cytotoxicity against five human cancer (HeLa, HepG2, K562, MDA231, and NCI-H460) cell lines and a murine melanoma B16 F10 cell line by MTT assay. Compounds 1-15 showed cytotoxic activities, especially compounds 3, 4, 8, 10, and 12. These five compounds showed broad spectrum activities against all the tested cancer cell lines with IC50 ranging from 9.2 to 35.5µM. The study supports that eremophilenolides and eudesmane-type sesquiterpenes occur mainly in the genus Parasenecio and can be used as a chemosystematic marker of the genus.


Assuntos
Antineoplásicos Fitogênicos/farmacocinética , Asteraceae/química , Sesquiterpenos/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Melanoma Experimental , Camundongos , Estrutura Molecular , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos de Eudesmano/química , Sesquiterpenos de Eudesmano/isolamento & purificação , Sesquiterpenos de Eudesmano/farmacocinética
12.
Cell Stress Chaperones ; 22(1): 55-65, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27812888

RESUMO

Recent studies have shown 5-hydroxymethyl-2-furfural (5-HMF) has favorable biological effects, and its neuroprotection in a variety of neurological diseases has been noted. Our previous study showed that treatment of 5-HMF led to protection against permanent global cerebral ischemia. However, the underlying mechanisms in cerebral ischemic injury are not fully understood. This study was conducted to investigate the neuroprotective effect of 5-HMF and elucidate the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway mechanism in the striatum after transient global cerebral ischemia. C57BL/6 mice were subjected to bilateral common carotid artery occlusion for 20 min and sacrificed 24 h after reperfusion. 5-HMF (12 mg/kg) or an equal volume of vehicle was intraperitoneally injected 30 min before ischemia and 5 min after the onset of reperfusion. At 24 h after reperfusion, neurological function was evaluated by neurological disability status scale, locomotor activity test and inclined beam walking test. Histological injury of the striatum was observed by cresyl violet staining and terminal deoxynucleotidyl transferase (TdT)-mediated dNTP nick end labeling (TUNEL) staining. Oxidative stress was evaluated by the carbonyl groups introduced into proteins, and malondialdehyde (MDA) levels. An enzyme-linked immunosorbent assay (ELISA)-based measurement was used to detect Nrf2 DNA binding activity. Nrf2 and its downstream ARE pathway protein expression such as heme oxygenase-1, NAD (P)H:quinone oxidoreductase 1, glutamate-cysteine ligase catalytic subunit and glutamate-cysteine ligase modulatory subunit were detected by western blot. Our results showed that 5-HMF treatment significantly ameliorated neurological deficits, reduced brain water content, attenuated striatum neuronal damage, decreased the carbonyl groups and MDA levels, and activated Nrf2/ARE signaling pathway. Taken together, these results demonstrated that 5-HMF exerted significant antioxidant and neuroprotective effects following transient cerebral ischemia, possibly through the activation of the Nrf2/ARE signaling pathway.


Assuntos
Furaldeído/análogos & derivados , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Elementos de Resposta Antioxidante/fisiologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Furaldeído/farmacologia , Glutamato-Cisteína Ligase/metabolismo , Heme Oxigenase-1/metabolismo , Locomoção/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
13.
J Asian Nat Prod Res ; 17(12): 1196-203, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26666298

RESUMO

1,4-Naphthoquinone (1) and a new coumarin (3) were isolated from Ajania salicifolia, together with two known compounds (2, 4). The structures and stereochemistry of new compounds were elucidated using spectroscopic methods. Two compounds exhibited potent ABTS cation radical scavenging activities with IC50 values ranging 7.97-8.44 µM. Two quinones (1, 2) exhibited moderate cytotoxic activity against the human cancer cell lines (Hela, HepG2, and K562) with IC50 values of 11.24-35.15 µM in vitro. This is the first report of naphthoquinone in the genus Ajania.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Asteraceae/química , Cumarínicos/isolamento & purificação , Cumarínicos/farmacologia , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Naftoquinonas/isolamento & purificação , Naftoquinonas/farmacologia , Quinonas/isolamento & purificação , Quinonas/farmacologia , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Sobrevivência Celular/efeitos dos fármacos , Cumarínicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Sequestradores de Radicais Livres/química , Células HeLa , Células Hep G2 , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Naftoquinonas/química , Quinonas/química
14.
Artigo em Chinês | MEDLINE | ID: mdl-26827534

RESUMO

OBJECTIVE: To extract two kinds of phenols 4-hydroxy-3, 5-dimethoxy-4-(2-oxopropyl) cyclohexa-2, 5-dien-l-one and 6-methoxy-5,7-dihydroxy coumarin (named as I and H compounds respectively) from Ajania salicifolia and to investigate their antioxidation and cytotoxicity to tumors and explore their pro-apoptosis mechanism. METHODS: The antioxidant activities of two compounds were assessed by ABTS and DPPH radical-scavenging assays. Two compounds were evaluated for their cytotoxicity against human chronic myelogenous leukemia (K562) cells using the MIT assay. The expression of NF-kappaB P65 mRNA in K562 apoptotic cells was measured by reverse transcription-polymerase chain reaction (RT-PCR), real-time quantitative PCR. In addition, protein expression levels of the NF-ICB P65, p-Akt, Fas, P-catenina and E-cadherin were also measured by Western blot. RESULTS: (1) We found that compound I displayed significant inoxidizability, while compound II had no obvious antioxidizability. (2) In cytotoxicity experiments, compound I didn't display cytotoxicity while compound H displayed obvious cytotoxicity. (3) Compared with the blank group, the expression of NF-kappaB P65 mRNA in K562 cell after treatment with compound II was obviously up-regulated. (4) Compared with the blank group, the expression levels of NF-kappaB P65, Fas, beta-catenina and E-cadherin were significantly increased in compound II treated groups and it appeared obvious dose-effect relationship between the expression of protein and drug concentration. CONCLUSION: Two phenols have obvious antioxidizability and cytotoxicity respectively. On the one hand, the tumor-suppressing mechanism of compound II maybe act by up-regulation the expression of NF-kappaB P65 and Fas protein; thereby, affecting the classical Fas apoptosis signaling pathways. On the other hand, it can also up-regulate the expression of protein beta-catenin and E-cadherin, which participate in the adhesion between cells, and accordingly, playing an important role in preventing the proliferation and metastasis of cancer cells.


Assuntos
Apoptose , Asteraceae/química , Fenóis/química , Transdução de Sinais , Antígenos CD , Caderinas/metabolismo , Humanos , Células K562 , Proteína Oncogênica v-akt/metabolismo , Fator de Transcrição RelA/metabolismo , Regulação para Cima , beta Catenina/metabolismo , Receptor fas/metabolismo
15.
World J Gastroenterol ; 20(41): 15335-42, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25386082

RESUMO

AIM: To investigate the effects and underlying mechanisms of resveratrol and genistein on contractile responses of rat gastrointestinal smooth muscle. METHODS: Isolated strips of gastrointestinal smooth muscle from Spraque-Dawley rats were suspended in organ baths containing Kreb's solution, and the contractility of smooth muscles was measured before and after incubation with resveratrol and genistein, and the related mechanisms were studied by co-incubation with various inhibitors. RESULTS: Resveratrol and genistein dose-dependently decreased the resting tension, and also reduced the mean contractile amplitude of gastrointestinal smooth muscle. Estrogen receptor blockades (ICI 182780 and tamoxifen) failed to alter the inhibitory effects induced by resveratrol and genistein. However, their effects were attenuated by inhibitions of α-adrenergic receptor (phentolamine), nitric oxide synthase (levorotatory-NG-nitroarginine), ATP-sensitive potassium channels (glibenclamide), and cyclic adenosine monophosphate (SQ22536). In high K(+)/Ca(2+)-free Kreb's solution containing 0.01 mmol/L egtazic acid, resveratrol and genistein reduced the contractile responses of CaCl2, and shifted its cumulative concentration-response curves rightward. CONCLUSION: Resveratrol and genistein relax gastrointestinal smooth muscle via α-adrenergic receptors, nitric oxide and cyclic adenosine monophosphate pathways, ATP-sensitive potassium channels, and inhibition of L-type Ca(2+) channels.


Assuntos
Duodeno/efeitos dos fármacos , Motilidade Gastrointestinal/efeitos dos fármacos , Genisteína/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Fitoestrógenos/farmacologia , Estilbenos/farmacologia , Estômago/efeitos dos fármacos , Animais , Canais de Cálcio Tipo L/efeitos dos fármacos , Canais de Cálcio Tipo L/metabolismo , AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Duodeno/metabolismo , Feminino , Mucosa Gástrica/metabolismo , Técnicas In Vitro , Canais KATP/agonistas , Canais KATP/metabolismo , Músculo Liso/metabolismo , Óxido Nítrico/metabolismo , Ratos Sprague-Dawley , Receptores Adrenérgicos alfa/efeitos dos fármacos , Receptores Adrenérgicos alfa/metabolismo , Resveratrol , Transdução de Sinais/efeitos dos fármacos
17.
Artigo em Chinês | MEDLINE | ID: mdl-24175548

RESUMO

OBJECTIVE: To observe and compare the effects of 17beta-estradiol (EST) on the phasic and tonic contractile activities of the uterine smooth muscles of SD rats in vitro. METHODS: Different concentrations of 17beta-estradiol were added into the perfusion muscular sockets containing uterine smooth muscles of SD rats, and the activities of muscle contraction were recorded at the same time. RESULTS: 17beta-estradiol had obvious depression effects on spontaneous rhythmic contraction of the uterine smooth muscles in a concentration-dependent manner, it could considerably decrease muscular tension, the mean amplitudes and frequencies of contractile waves (P < 0.01); it could also suppress the uterine contraction stimulated by KCl, CaCl2 or prostaglandin F2alpha (PGF2alpha). Based on the contraction of uterine smooth muscle stimulated by KCl, IC50 was 7.278 micromol/L and pD2 was -0.862 when calculated by linear regression method. 17beta-estradiol could also inhibit the maximal CaC12 contraction of uterine smooth muscle in the Ca2+ free Krebs solution, which the ECQ was 1.422 x 10(-3) mol/L, pD2 was 2.847 (control), but the E50 was 3.028 x 10(-3) mol/L, p2 was 2.519 (added with EST) when calculated by linear regression method. CONCLUSION: The depression effects of 17beta-estradiol on the spontaneous rhythmic contraction and activated contraction of the uterine smooth muscles of SD rats could be mediated through the blockage of C2+ influx through potential-dependent Ca2+ channels of plasma membrane.


Assuntos
Estradiol/farmacologia , Músculo Liso/efeitos dos fármacos , Contração Uterina/efeitos dos fármacos , Animais , Feminino , Miométrio/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
18.
Sheng Li Xue Bao ; 65(1): 8-18, 2013 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-23426508

RESUMO

Phytoestrogens, a group of plant-derived non-steroidal compounds that can behave as estrogens by binding to estrogen receptors, have drawn great attention for their potentially beneficial effects on human health. However, there are few studies investigating the potential side effects of phytoestrogens on the reproductive system. The present study was to elucidate the effects of 17ß-estradiol (E2), progesterone (P4), and phytoestrogens genistein (Gen), resveratrol (Res), and phloretin (Phl) on eosinophilic infiltration of the ovariectomized rat uterus and endometrial vascular permeability, and to analyze the underlying mechanisms. The ovariectomized rats received daily subcutaneous injections of E2, E2+P4, P4, Gen, Res, Phl, or an equivalent volume of vehicle for 21 days, and sham-operated animals (Sham rats) were used as the controls. Hematoxylin-eosin staining revealed a marked increase in uterine eosinophilic infiltrations in ovariectomized rats treated with E2, E2+P4 or P4, which was associated with increased expression of vascular endothelial growth factor (VEGF), nuclear factor-κB (NF-κB), and tumor necrosis factor-α (TNF-α) proteins as determined by immunohistochemical and Western blot analysis. However, all three phytoestrogens had no markedly effect on the uterine eosinophilic infiltration and the expressions of VEGF, NF-κB, and TNF-α in the uterus of ovariectomized rats. Our data demonstrate that E2 alone or in combination with P4 increases uterine eosinophilic infiltration which is related with vascular hyperpermeability caused by VEGF, NF-κB and TNF-α, whereas phytoestrogens Gen, Res, and Phl, have no such an effect.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Estrogênios/farmacologia , Fitoestrógenos/farmacologia , Útero/efeitos dos fármacos , Animais , Eosinófilos/citologia , Estradiol/farmacologia , Feminino , Genisteína/farmacologia , NF-kappa B/metabolismo , Ovariectomia , Permeabilidade , Floretina/farmacologia , Progesterona/farmacologia , Ratos , Resveratrol , Estilbenos/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 8): m1094-5, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22090869

RESUMO

In the bimetallic cyanide-bridged title complex, [Fe(0.98)HoRu(0.02)(CN)(6)(C(3)H(7)NO)(4)(H(2)O)(3)]·H(2)O, the Ho(III) ion is in a slightly distorted square-anti-prismatic arrangement formed by seven O atoms from four dimethyl-formamide (DMF) mol-ecules and three water mol-ecules, and one N atom from a bridging cyanide group connected with the Fe(III) atom which is octa-hedrally coordinated by six cyanide groups. In the crystal, mol-ecules are held together through O-H⋯N and O-H⋯O hydrogen-bonding inter-actions to form a three-dimensional framework. Elemental analysis of one of the precursors and the crystal shows that there is a slight contamination of Fe by Ru. The Fe site displays, therefore, small substitutional disorder with site-occupancy factors Fe/Ru = 0.98:0.02. The two methyl groups of two dimethyl-formamide ligands are positionally disordered with site-occupancy factors of 0.44 (3):0.56 (3) and 0.44 (3):0.56 (3).

20.
Zhong Yao Cai ; 34(5): 704-7, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21954553

RESUMO

OBJECTIVE: To study the chemical constituents of the herb of Antenoron filiforme. METHODS: The constituents were separated by column chromatography and their structures were elucidated by spectral data analyses. RESULTS: Eleven compounds were isolated from the ethanol extract of A. filiforme and identified as, bronane-5-hydroxy-2-O-beta-D-glucopyranoside (I), adenosine (II), bonaroside (III), rhamnetin (IV), hyperoside (V), rhamnetin-3-O-beta-D-galactopyranoside (VI), kaempferol-3, 7-O-bis-alpha-L-rhamnopyranoside (VII), stigmasterol (VIII), nonacosanoic acid (IX), daucosterol (X), 3beta-sitosterol (XI). CONCLUSION: All compounds are obtained from A. filiforme for the first time.


Assuntos
Flavonóis/isolamento & purificação , Glucosídeos/isolamento & purificação , Polygonaceae/química , Sitosteroides/isolamento & purificação , Adenosina/química , Adenosina/isolamento & purificação , Flavonóis/química , Glucosídeos/química , Estrutura Molecular , Plantas Medicinais/química , Quercetina/análogos & derivados , Quercetina/química , Quercetina/isolamento & purificação , Sitosteroides/química , Estigmasterol/química , Estigmasterol/isolamento & purificação
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