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1.
Aging (Albany NY) ; 16(6): 5000-5026, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38517361

RESUMO

D-galactose (D-gal) administration was proven to induce cognitive impairment and aging in rodents' models. Geraniol (GNL) belongs to the acyclic isoprenoid monoterpenes. GNL reduces inflammation by changing important signaling pathways and cytokines, and thus it is plausible to be used as a medicine for treating disorders linked to inflammation. Herein, we examined the therapeutic effects of GNL on D-gal-induced oxidative stress and neuroinflammation-mediated memory loss in mice. The study was conducted using six groups of mice (6 mice per group). The first group received normal saline, then D-gal (150 mg/wt) dissolved in normal saline solution (0.9%, w/v) was given orally for 9 weeks to the second group. In the III group, from the second week until the 10th week, mice were treated orally (without anesthesia) with D-gal (150 mg/kg body wt) and GNL weekly twice (40 mg/kg body wt) four hours later. Mice in Group IV were treated with GNL from the second week up until the end of the experiment. For comparison of young versus elderly mice, 4 month old (Group V) and 16-month-old (Group VI) control mice were used. We evaluated the changes in antioxidant levels, PI3K/Akt levels, and Nrf2 levels. We also examined how D-gal and GNL treated pathological aging changes. Administration of GNL induced a significant increase in spatial learning and memory with spontaneously altered behavior. Enhancing anti-oxidant and anti-inflammatory effects and activating PI3K/Akt were the mechanisms that mediated this effect. Further, GNL treatment upregulated Nrf2 and HO-1 to reduce oxidative stress and apoptosis. This was confirmed using 99mTc-HMPAO brain flow gamma bioassays. Thus, our data suggested GNL as a promising agent for treating neuroinflammation-induced cognitive impairment.


Assuntos
Monoterpenos Acíclicos , Disfunção Cognitiva , Galactose , Humanos , Camundongos , Animais , Galactose/toxicidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Doenças Neuroinflamatórias , Fator 2 Relacionado a NF-E2/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Estresse Oxidativo , Envelhecimento/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Antioxidantes/farmacologia , Modelos Animais de Doenças , Inflamação/tratamento farmacológico
2.
Saudi J Med Med Sci ; 12(1): 17-26, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38362098

RESUMO

Background: Hepatotoxicity caused by CCL4 is well known. Geraniol (GNL) has high antioxidant effect that can induces liver regeneration. However, the protective effect of GNL effect on CCL4-induced hepatorenal toxicity in pregnant mice has not yet been studied. Objective: To investigate whether GNL could protect against oxidative stress induced by CCL4 via the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, which is regulated by phosphatidylinositol 3 kinase/protein kinase B (PI3K/AKT), and has been found to have protective effects on renal and hepatic tissues. Materials and Methods: Forty-eight female albino mice weighing 25-30 g were randomly allocated to 4 groups: Group I served as a control; Group II received a toxicity-inducing single dose of 15 µL of CCL4 on the 4th day after mating; Group III received 40 mg/kg GNL + CCL4 (with GNL from the 1st day of assimilation to delivery); and Group IV received GNL alone from the 1st day of assimilation to the end of the delivery period. GNL was evaluated for its protective effects on hepatotoxicity in CCL4-treated pregnant mice. Litter size, weight, survival rate, and resorption were recorded. In addition, H & E staining was done for liver and kidney pathology as well as biochemical markers and oxidative markers malondialdehyde, superoxide dismutase, and catalase were analyzed. Results: CCL4 significantly reduced survival rate and increased resorption after exposure. Alanine transaminase and aspartate aminotransferase concentrations in the serum, tissue MDA, blood urea nitrogen, and creatinine were increased after CCL4 exposure. GNL improved enzyme and antioxidant levels and prevented CCL4-induced hepatic injury in mice. Caspase-3 cleavage was decreased by GNL, which increased PI3K, phosphorylated AKT, Nrf2, and B-cell lymphoma 2. Conclusion: GNL demonstrates a protective effect against CCl4-induced hepatorenal toxicity, mediated through the activation of the PI3K/AKT signaling pathway and the upregulation of Nrf2. These findings highlight the potential therapeutic implications of GNL in mitigating oxidative stress and inflammation in liver and kidney tissues.

3.
Nutrients ; 15(5)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36904106

RESUMO

Stroke is one of the main causes of mortality and disability, and it is due to be included in monetary implications on wellbeing frameworks around the world. Ischemic stroke is caused by interference in cerebral blood flow, leading to a deficit in the supply of oxygen to the affected region. It accounts for nearly 80-85% of all cases of stroke. Oxidative stress has a significant impact on the pathophysiologic cascade in brain damage leading to stroke. In the acute phase, oxidative stress mediates severe toxicity, and it initiates and contributes to late-stage apoptosis and inflammation. Oxidative stress conditions occur when the antioxidant defense in the body is unable to counteract the production and aggregation of reactive oxygen species (ROS). The previous literature has shown that phytochemicals and other natural products not only scavenge oxygen free radicals but also improve the expressions of cellular antioxidant enzymes and molecules. Consequently, these products protect against ROS-mediated cellular injury. This review aims to give an overview of the most relevant data reported in the literature on polyphenolic compounds, namely, gallic acid, resveratrol, quercetin, kaempferol, mangiferin, epigallocatechin, and pinocembrin, in terms of their antioxidant effects and potential protective activity against ischemic stroke.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Antioxidantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Polifenóis/farmacologia , Neuroproteção , Acidente Vascular Cerebral/metabolismo , Estresse Oxidativo , Isquemia
4.
Molecules ; 27(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36500446

RESUMO

Beta-Caryophyllene (BCP), a natural bicyclic sesquiterpenes, is an abundant biomolecule in red pepper and other plants. Recently, it was reported to reduce the growth and the proliferation as well as enhance the apoptosis in numerous cancer cells, including colorectal, ovarian, bladder cancer and lung cancer. On the other hand, the combination therapy of cisplatin (CDDP) with other phytochemical compounds has synergistically enhanced the killing effect of CDDP on several types of cancer. In the current model, we have tested the role of BCP in enhancing the anti-tumor activity of CDDP on lung cancer cell lines. The results showed that BCP is not toxic at moderate doses and it can prevent lung cancer progression in doses above 75 µM. However, when being combined with CDDP, BCP improved the former chemotherapeutic function through regulating cell cycle, apoptosis and EMT signaling molecules. Gene and protein expression analysis showed that the combined treatment of CDDP and BCP significantly upregulated the level of the cyclin-dependent kinase inhibitor, CDKN1A, and the inhibitor of the apoptosis, BCL-xl2. In addition, the combination treatment reduced the protein level of the apoptosis regulator, BCL-2. Moreover, BCP appears to prohibit the EMT process that is associated with CDDP chemotherapy since the combination treatment induced a significant increase in the level of the epithelial cell marker E-cad that was reduced in CDDP-treated cells. In agreement with that, the combined treatment managed to modulate the effect of CDDP on the mesenchymal transcription factor ZEB-2. Additionally, molecular docking has been conducted to check the virtual interaction of BCP with these and other signaling molecules, but only cyclin-dependent kinase CDK6 was found to virtually bind with BCP, and at four sites with higher and stable biding energy (-7.8). Together, these data indicate that BCP enhances CDDP chemotherapeutic function through regulating the cell cycle, the apoptosis and EMT signaling molecules.


Assuntos
Antineoplásicos , Neoplasias Pulmonares , Humanos , Cisplatino , Simulação de Acoplamento Molecular , Proliferação de Células , Neoplasias Pulmonares/metabolismo , Apoptose , Ciclo Celular , Linhagem Celular , Quinases Ciclina-Dependentes , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos
5.
Braz J Biol ; 84: e259100, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35588519

RESUMO

The potential of Alhagi maurorum (Boiss.) aqueous extract (AME), used in traditional medicine for treatment or prevention of urolithiasis, to dissolve calcium oxalate stones in vitro was evaluated. In order to determine the litholytic potential of the extract, Calcium oxalate urinary stones were incubated during 12 weeks under continuous shaking in the presence of AME, Rowanix or NaCl 9 g/mL solution were used as controls. After the incubation period, the residual weight of the treated calculi was determined and the rate of dissolution was calculated. The medium pH variation was measured and changes in the calcium oxalate crystals at the stone surface were assessed using a scanning electron microscope (SEM). The results showed a significant dissolution effect for the extract on the kidney calculi during the experimentation period. At the end of the experiment, the percentages of calculi weight decrease were 41.23, 4.97 and 55.67% for the extract, NaCl solution and Rowanix, respectively. Gas Chromatography analysis revealed mainly the presence of the following phyto-compounds: Cyclopropenone, 2,3-diphenyl; 1-Nonadecanol; methyl-alpha-D-mannopyranoside; cis-9-Hexadecenal. These compounds unarguably play crucial roles in the health care system especially in cancer treatment and many other diseases including urolithiasis. The urinary stone dissolution, independent of medium pH, could be attributed to formation of complexes between the phytochemical compounds in the extract and the calculi.


Assuntos
Cálculos , Urolitíase , Oxalato de Cálcio/química , Oxalato de Cálcio/urina , Humanos , Arábia Saudita , Cloreto de Sódio , Urolitíase/urina
6.
Clin Exp Pharmacol Physiol ; 49(6): 613-623, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35275419

RESUMO

In recent years, oncotherapy has received considerable attention concerning plant polyphenols. Increasing evidence suggests that because of the efficiency of polyphenols, they may have anti-tumour effects in various cancers. However, their regulatory structures remain elusive. Long non-coding RNAs (lncRNAs) have been identified in the regulation of various forms of tumorigenesis and tumour development. Long non-coding RNAs have recently emerged as regulatory eukaryotic transcripts and therapeutic targets with important and diverse functions in health and diseases. LncRNAs may be associated with the initiation, development, and progression of cancer. This review summarizes the research on the modulatory effects of IncRNAs and their roles in mediating cellular processes. The mechanisms of action of polyphenols underlying their therapeutic effects on cancers are also discussed. Based on our review, polyphenols might facilitate a significant epigenetic modification as part of their tissue- and/or cell-related biological effects. This finding may be attributed to their interaction with cellular signalling pathways involved in chronic diseases. Certain lncRNAs might be the target of specific polyphenols, and some critical signalling processes involved in the intervention of cancers might mediate the therapeutic roles of polyphenols.


Assuntos
Neoplasias , RNA Longo não Codificante , Carcinogênese , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Polifenóis/farmacologia , Polifenóis/uso terapêutico , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA não Traduzido
7.
Biochem Cell Biol ; 99(3): 374-384, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33103467

RESUMO

Chemo-resistance and metastasis are the most common causes of breast cancer recurrence and death. Thidiazuron (TDZ) is a plant growth regulator (phytohormone) whose biological effects on humans and animals has not yet been determined. In this study, we investigated the anticancer activity of this phytohormone on the drug resistant-triple negative breast cancer cell line MDA-MB-231. Treatment of the breast cancer cells with TDZ (1-50 µmol/L) caused more stressful environment and induced a significant increase in active caspase-positive cells. In addition, TDZ treatment (5 and 10 µmol/L) significantly attenuated the migration and the invasiveness of these highly metastatic cancer cells. Mechanistically, TDZ reduces cancer progression and invasiveness by targeting miR-202-5p, which stimulates the expression of phosphatase and tensin homolog (PTEN), the tumor suppressor that downregulates the PI3K-Akt signaling pathway. Treatment with TDZ significantly upregulates miRNA-132, the suppressor of breast cancer proliferation, which is also implicated in dysregulation of the TEN-Akt-NFκB signaling pathway. Interestingly, our molecular docking analysis revealed a potential non-covalent interaction between TDZ and Akt, PTEN, and PI3K. These findings suggest that TDZ suppresses breast cancer metastasis by targeting miRNA-132, the miR-202-5p-PTEN axis, and the PI3K-Akt signaling pathway downstream.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , MicroRNAs/genética , PTEN Fosfo-Hidrolase/metabolismo , Compostos de Fenilureia/farmacologia , Tiadiazóis/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Feminino , Humanos , Invasividade Neoplásica , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células Tumorais Cultivadas
8.
Int J Mol Sci ; 22(1)2020 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-33379332

RESUMO

In this study, kaempferol (KFL) shows hepatoprotective activity against zearalenone (ZEA)-induced oxidative stress and its underlying mechanisms in in vitro and in vivo models were investigated. Oxidative stress plays a critical role in the pathophysiology of various hepatic ailments and is normally regulated by reactive oxygen species (ROS). ZEA is a mycotoxin known to exert toxicity via inflammation and ROS accumulation. This study aims to explore the protective role of KFL against ZEA-triggered hepatic injury via the PI3K/Akt-regulated Nrf2 pathway. KFL augmented the phosphorylation of PI3K and Akt, which may stimulate antioxidative and antiapoptotic signaling in hepatic cells. KFL upregulated Nrf2 phosphorylation and the expression of antioxidant genes HO-1 and NQO-1 in a dose-dependent manner under ZEA-induced oxidative stress. Nrf2 knockdown via small-interfering RNA (siRNA) inhibited the KFL-mediated defence against ZEA-induced hepatotoxicity. In vivo studies showed that KFL decreased inflammation and lipid peroxidation and increased H2O2 scavenging and biochemical marker enzyme expression. KFL was able to normalize the expression of liver antioxidant enzymes SOD, CAT and GSH and showed a protective effect against ZEA-induced pathophysiology in the livers of mice. These outcomes demonstrate that KFL possesses notable hepatoprotective roles against ZEA-induced damage in vivo and in vitro. These protective properties of KFL may occur through the stimulation of Nrf2/HO-1 cascades and PI3K/Akt signaling.


Assuntos
Apoptose/efeitos dos fármacos , Quempferóis/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Zearalenona/toxicidade , Animais , Biomarcadores/metabolismo , Citocinas/metabolismo , Dano ao DNA , Técnicas de Silenciamento de Genes , Heme Oxigenase-1/metabolismo , Células Hep G2 , Humanos , Mediadores da Inflamação/metabolismo , Quempferóis/química , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/patologia , Masculino , Camundongos , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima/efeitos dos fármacos
9.
Nat Prod Res ; 25(11): 1047-58, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21726127

RESUMO

Total oligomer flavonoids (TOF) enriched and ethyl acetate (EA) extracts from Rhamnus alaternus induce apoptotic death in human chronic myelogenous leukaemia K562 cell line, as demonstrated by gel electrophoresis, which demonstrates the characteristic ladder patterns of DNA fragmentation and the proteolytic cleavage of poly(ADP ribose) polymerase (PARP). The effect of R. alaternus extract in reducing oxidative stress was evaluated by anti-lipid peroxidation which was monitored by measuring malondialdehyde level in K562 cultured cells. The TOF and EA extracts were found to be effective to protect against lipid peroxidation. Their IC50 values were 196 and 273 µg mL⁻¹, respectively. These findings suggest that R. alaternus extracts exhibit potential antioxidant and proapoptotic properties.


Assuntos
Leucemia Eritroblástica Aguda/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Rhamnus/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Fragmentação do DNA/efeitos dos fármacos , Humanos , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Poli(ADP-Ribose) Polimerases/metabolismo
10.
Chem Biol Interact ; 174(1): 1-10, 2008 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-18511029

RESUMO

The effect of extracts obtained from Rhamnus alaternus L. leaves on genotoxicity and SOS response induced by aflatoxin B(1) (10 microg/assay) as well as nifuroxazide (20 microg/assay) was investigated in a bacterial assay system, i.e., the SOS chromotest with Escherichia coli PQ37. The evaluation of the mutagenic and antimutagenic actions of the same extracts against the sodium azide (1.5 microg/plate)-induced mutagenicity was assayed using the Salmonella typhimurium assay system. The R. alaternus tested extracts exhibited no genotoxicity either with or without the external S9 activation mixture. However, all the extracts, particularly aqueous extract (A) and its chloroformic fraction (A(2)) significantly decreased the genotoxicity induced by aflatoxin B(1) and nifuroxazide. Moreover, the different extracts showed no mutagenicity when tested with Salmonella typhimurium strains TA1535 and TA1538 either with or without the S9 mix. Aqueous extract as well as its A(2) fraction exhibited the highest level of protection towards the direct mutagen, sodium azide-induced response in TA1535 strain with mutagenicity inhibition percentages of 83.6% and 91.4%, respectively, at a dose of 250 microg/plate. The results obtained by the Ames test assay confirm those of SOS chromotest. These same active extracts exhibited high xanthine oxidase (XOD) inhibiting with respective IC(50) values of 208 and 137 microg/ml, and superoxide anion-scavenging effects (IC(50) values of 132 and 117 microg/ml) when tested in the XOD enzymatic assay system. Our findings emphasize the potential of R. alaternus to prevent mutations and also its antioxidant effect.


Assuntos
Aflatoxina B1/toxicidade , Antioxidantes/farmacologia , Hidroxibenzoatos/toxicidade , Mutagênese/efeitos dos fármacos , Nitrofuranos/toxicidade , Extratos Vegetais/farmacologia , Rhamnus/química , Azida Sódica/toxicidade , Escherichia coli/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Testes de Mutagenicidade , Mutagênicos/toxicidade , Salmonella typhimurium/efeitos dos fármacos , Superóxidos/metabolismo , Xantina Oxidase/antagonistas & inibidores
11.
Drug Chem Toxicol ; 31(1): 37-60, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18161507

RESUMO

Mutagenic and antimutagenic activities against direct acting mutagens, nifuroxazide (NF) and sodium azide (SA), and indirect acting mutagen aflatoxin B1 (AFB1) of extracts prepared from aerial parts of Pituranthos tortuosus were investigated in bacterial assay systems (i.e., the Ames test with Salmonella typhimurium TA100, TA98, TA1538, TA1535, and the SOS chromotest with Escherichia coli PQ 37). It was found that all extracts obtained from P. tortuosus decreased the mutagenicity induced by AFB1 (10 microg/assay), SA (1.5 microg/assay), and NF (20 microg/assay). Ethyl acetate, acetone, methanol, and total oligomer flavenoid extracts exhibited the highest inhibition level of mutagenicity induced by the indirect mutagen AFB1. In addition, antiproliferative and apoptotic properties of these extracts have also been reported using two leukemia cell lines, L1210 and K562. The results revealed that all extracts showed a significant cytotoxic effect on these cell lines, and the effect was greater in the presence of human K562 chronic myelogenous leukemia cells, whereas they do not induce apoptosis.


Assuntos
Antimutagênicos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Apiaceae , Apoptose/efeitos dos fármacos , DNA Bacteriano/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Mutagênicos/farmacologia , Salmonella typhimurium/efeitos dos fármacos , Aflatoxina B1/farmacologia , Animais , Antimutagênicos/química , Antimutagênicos/toxicidade , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/toxicidade , Apiaceae/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Escherichia coli/genética , Humanos , Hidroxibenzoatos/farmacologia , Células K562 , Camundongos , Mutagênicos/química , Mutagênicos/toxicidade , Mutação/efeitos dos fármacos , Nitrofuranos/farmacologia , Componentes Aéreos da Planta , Extratos Vegetais/farmacologia , Salmonella typhimurium/genética , Azida Sódica/farmacologia
12.
Drug Chem Toxicol ; 31(1): 61-80, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18161508

RESUMO

A pronounced antiproliferative effect on human leukemia K562 cells was shown with flavonoid-enriched extracts from Rhamnus alaternus roots and leaves, with, respectively, IC(50) values of 165 and 210.73 microg/mL. High DPPH radical-scavenging activity (7.21 and 18.84 microg/mL, respectively) and antioxidative effects using the xanthine oxidase assay (IC(50) values of 83.33 and 103.96 microg/mL, respectively) were detected in the presence of the two tested extracts. Although no mutagenic effect was observed when using the Salmonella typhimurium assay system with TA1535 and TA100 strains, the two tested extracts exhibited a high-level protection toward the direct mutagen, sodium azide-induced response.


Assuntos
Antimutagênicos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Proliferação de Células/efeitos dos fármacos , DNA Bacteriano/efeitos dos fármacos , Mutação/efeitos dos fármacos , Rhamnus , Salmonella typhimurium/efeitos dos fármacos , Animais , Antimutagênicos/química , Antimutagênicos/toxicidade , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/toxicidade , Antioxidantes/química , Antioxidantes/toxicidade , Relação Dose-Resposta a Droga , Flavonoides/análise , Sequestradores de Radicais Livres/farmacologia , Humanos , Concentração Inibidora 50 , Células K562 , Camundongos , Componentes Aéreos da Planta , Extratos Vegetais/farmacologia , Raízes de Plantas , Rhamnus/química , Salmonella typhimurium/genética , Azida Sódica/farmacologia , Superóxidos/química , Xantina Oxidase/antagonistas & inibidores , Xantina Oxidase/metabolismo
13.
Chem Biol Interact ; 168(3): 171-83, 2007 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-17512922

RESUMO

The ability of three Rhamnus alaternus leaves extracts on antigenotoxic and gene expression level effects was respectively investigated in a bacterial assay system, i.e. the SOS chromotest with Escherichia coli PQ37 and in human K562 lymphoblast cell line. Total oligomers flavonoids (TOF) enriched, methanol and ethyl acetate extracts were prepared from powdered R. alaternus leaves and characterized quantitatively for the presence of polyphenolic compounds. We explored the response to oxidative stress using the transcriptional profile of genes in K562 cells stressed with H2O2 after incubation with plant extracts. For this purpose, we used a cDNA microarrays containing 82 genes related to cell defense, essentially represented by antioxidant and DNA repair genes. Analysis revealed that SOD1, AOE 372, TXN genes involved in the antioxidant defense system and XPC, LIG4, POLD2, PCNA genes implied in the DNA repair system were among the most expressed ones in the presence of the tested extracts. These results were in accordance with those obtained when we tested the antigenotoxic and antioxidant effects of the same extracts with, respectively the SOS chromotest and the xanthine/xanthine oxidase enzymatic assay system. The effect of the tested extracts on SOS response induced by both Aflatoxin B1 (AFB1: 10 microg/assay) and nifuroxazide (20 microg/assay) showed that the TOF extract exhibited the highest antimutagenic level towards the indirect mutagen AFB1. Whereas ethyl acetate extract showed the highest antimutagenic effect towards the direct mutagen, nifuroxazide. None of the tested extracts induced mutagenic activity. However all the tested extracts exhibited xanthine oxidase inhibiting and superoxide anions scavenging effects. R. alaternus extracts contain compounds with significant antioxidant and antigenotoxic activities. These compounds modulate gene expression as detected by using cDNA arrays.


Assuntos
Flavonoides/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Peróxido de Hidrogênio/toxicidade , Fenóis/farmacologia , Rhamnus/química , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Flavonoides/química , Sequestradores de Radicais Livres/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/genética , Humanos , Testes de Mutagenicidade , Análise de Sequência com Séries de Oligonucleotídeos , Fenóis/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , RNA/genética , RNA/metabolismo , Superóxidos/metabolismo , Xantina Oxidase/antagonistas & inibidores , Xantina Oxidase/metabolismo
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