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1.
Am J Pharm Educ ; 80(8): 129, 2016 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-27899825

RESUMO

Point-of-care testing (POCT) is defined as laboratory testing conducted close to the site of patient care. Although performed originally primarily by clinical staff for acute conditions, recent advances in technology have made such testing possible for disease screening and prevention across a wide range of conditions in virtually any setting, and often by individuals with little or no training. With the ongoing evolution in POCT, numerous concerns have arisen about the quality and accuracy of the tests, comparability between multiple tests for the same endpoint, interpretation of test results, and whether and how results should be used for therapeutic decisions and included in a patient's medical record. The pharmacist is well-positioned to manage and interpret POCT performed outside of the usual clinical settings. However, educational and regulatory changes are needed to enable pharmacists to take on this emerging activity effectively.


Assuntos
Educação em Farmácia/tendências , Farmacêuticos , Sistemas Automatizados de Assistência Junto ao Leito/tendências , Testes Imediatos/tendências , Papel Profissional , Educação em Farmácia/legislação & jurisprudência , Educação em Farmácia/normas , Determinação de Ponto Final , Humanos , Legislação Farmacêutica , Sistemas Automatizados de Assistência Junto ao Leito/legislação & jurisprudência , Sistemas Automatizados de Assistência Junto ao Leito/normas , Testes Imediatos/legislação & jurisprudência , Testes Imediatos/normas , Reprodutibilidade dos Testes
2.
Crit Rev Toxicol ; 45(9): 765-98, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26610815

RESUMO

A radical is any molecule that contains one or more unpaired electrons. Radicals are normal products of many metabolic pathways. Some exist in a controlled (caged) form as they perform essential functions. Others exist in a free form and interact with various tissue components. Such interactions can cause both acute and chronic dysfunction, but can also provide essential control of redox regulated signaling pathways. The potential roles of endogenous or xenobiotic-derived free radicals in several human pathologies have stimulated extensive research linking the toxicity of numerous xenobiotics and disease processes to a free radical mechanism. In recent years, improvements in analytical methodologies, as well as the realization that subtle effects induced by free radicals and oxidants are important in modulating cellular signaling, have greatly improved our understanding of the roles of these reactive species in toxic mechanisms and disease processes. However, because free radical-mediated changes are pervasive, and a consequence as well as a cause of injury, whether such species are a major cause of tissue injury and human disease remains unclear. This concern is supported by the fact that the bulk of antioxidant defenses are enzymatic and the findings of numerous studies showing that exogenously administered small molecule antioxidants are unable to affect the course of most toxicities and diseases purported to have a free radical mechanism. This review discusses cellular sources of various radical species and their reactions with vital cellular constituents, and provides examples of selected disease processes that may have a free radical component.


Assuntos
Doença , Radicais Livres/toxicidade , Saúde , Animais , Radicais Livres/química , Humanos , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio
3.
4.
Can Pharm J (Ott) ; 146(6): 321-4, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24228046
6.
Am J Pharm Educ ; 76(2): 20, 2012 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-22438592

RESUMO

University-based continuing education (CE) fulfills an important role to support the professional development of pharmacists, advance the practice of pharmacy, and contribute to societal needs for research and healthcare services. Opportunities for pharmacists to engage in new models of patient care are numerous worldwide, particularly as pharmacists' scope of practice has expanded. Approaches to CE have changed to address the changing needs of pharmacists and now include a variety of approaches to support development of knowledge and skills. There is emphasis on the learning process as well as the knowledge, with the introduction of the concept of continuing professional development (CPD).As institutions of research and education, universities are uniquely positioned to bridge the gap between academic and practice environments, providing opportunities for translation of knowledge to practice. The Faculty of Pharmacy and Pharmaceutical Sciences at the University of Alberta is a provider of CE in Alberta, Canada, where an expanded scope of pharmacy practice includes prescribing, administering injections, accessing electronic patient records, and ordering laboratory tests. In this paper, the Faculty offers views about future directions for CE, including the integration of CE with core faculty activities, expanding the audience for CE, areas of focus for learning, and partnerships. Finally, we hope to ignite dialogue with others in the profession about the role and function of university-based CE.


Assuntos
Educação Continuada em Farmácia , Conhecimentos, Atitudes e Prática em Saúde , Farmacêuticos , Universidades , Canadá , Humanos , Assistência ao Paciente
7.
Am J Pharm Educ ; 76(10): 187, 2012 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-23275652

RESUMO

An appropriate balance between teaching, scholarship, and service is important for a faculty member to have a satisfying and successful career. The relative emphasis on each area normally changes during the course of a career. Although some level of scholarly output is an ongoing and fundamental expectation of all faculty members, this activity is too often given low priority, particularly among faculty members in practice areas who may have a minimal background in research and large demands on their time for teaching and clinical service. Addressing this issue requires establishing a shared commitment between administrators and faculty members, as well as identifying or developing education programs that will ensure research competence for practice faculty members. This paper provides insights into the role that scholarship and research should have for all pharmacy faculty members and provides suggestions for how to better advance this critical component within academic pharmacy.


Assuntos
Educação em Farmácia/normas , Docentes/normas , Farmacêuticos/normas , Farmácia/normas , Pesquisa/normas , Mobilidade Ocupacional , Humanos
8.
Am J Pharm Educ ; 74(8): 142, 2010 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-21179253

RESUMO

Although the education of student pharmacists and the practice of pharmacy in Canada have many similarities with that in the United States, there also are differences. The planning of curricula in pharmacy education is of particular importance to the advancement of pharmacy in Canada because of significant changes in the scope of practice in several provinces, and in how community pharmacy is reimbursed for the services it can, or should, provide. Greater dialog between Canadian and American pharmacists has the potential not only to impact practice on both sides of the border but also to improve collaborations among Canadian and American pharmacy educators. This article provides background information and some suggestions on how to build partnerships in pharmacy education between Canada and the United States. Consortia-like arrangements have some particular promise, as does engaging border-states and provinces in regional meetings and other activities. By working together, Canadian and US pharmacy educators have the opportunity to implement the best of what each has to offer and to devise new and better ways to educate future and existing pharmacists.


Assuntos
Educação em Farmácia/organização & administração , Cooperação Internacional , Alberta , Canadá , Comportamento Cooperativo , Legislação Farmacêutica/tendências , Ontário , Farmacêuticos , Prática Profissional , Estados Unidos
9.
Cell Biol Toxicol ; 26(2): 83-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19160065

RESUMO

Survival and apoptosis signaling pathways are altered concomitantly in response to numerous endogenous and exogenous stressors. The lipocalin family of small soluble proteins has been implicated in modulating apoptosis. However, the overall effect of these proteins has been variable, showing both pro- and anti-apoptotic activities. The goal of this minireview is to summarize the studies on lipocalins and apoptosis and consider what roles lipocalin-2 may play in cell death and survival.


Assuntos
Proteínas de Fase Aguda/fisiologia , Apoptose/fisiologia , Lipocalinas/fisiologia , Proteínas Oncogênicas/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Proteínas de Fase Aguda/antagonistas & inibidores , Animais , Sobrevivência Celular/fisiologia , Humanos , Lipocalina-2 , Lipocalinas/antagonistas & inibidores , Camundongos , Proteínas Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Transdução de Sinais/fisiologia
11.
Am J Pharm Educ ; 72(2): 34, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18496923

RESUMO

In 2005, the Council of Faculties and the Council of Deans within the American Association of Colleges of Pharmacy (AACP) formed a task force to review the status of the pharmacy faculty workforce and to identify factors that may influence the supply of and demand for pharmacy faculty members. This manuscript summarizes the Task Force on Faculty Workforce's findings and describes specific strategies needed to address the various issues facing the academy. Based on Task Force predictions, the academy will need approximately 1200 new faculty members over the next 10 years due to the creation of new pharmacy programs, the expansion of existing programs, faculty retirements, and recurring vacant faculty positions.


Assuntos
Educação em Farmácia , Docentes/organização & administração , Faculdades de Farmácia , Comitês Consultivos , Educação em Farmácia/estatística & dados numéricos , Docentes/estatística & dados numéricos , Humanos , Reorganização de Recursos Humanos , Aposentadoria/estatística & dados numéricos , Aposentadoria/tendências , Faculdades de Farmácia/estatística & dados numéricos , Estados Unidos , Recursos Humanos
13.
Am J Respir Cell Mol Biol ; 37(4): 405-13, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17575077

RESUMO

Reduction of glutathione disulfide (GSSG) to glutathione (GSH) by glutathione reductase (GR) enhances the efficiency of GSH-dependent antioxidant activities. However, GR-deficient (a1Neu) mice are less susceptible to acute lung injury from continuous exposure to > 95% O(2) (96 h: 6.9 +/- 0.1 g right lung/kg body versus room air 3.6 +/- 0.3) than are C3H/HeN control mice (10.6 +/- 1.3 versus 4.2 +/- 0.3, P < 0.001). a1Neu mice have greater hepatic thioredoxin (Trx)1 and Trx2 levels than do C3H/HeN mice, suggesting compensation for the absence of GR. a1Neu mice exposed to hyperoxia for 96 hours showed lower levels of inflammatory infiltrates in lungs than did similarly exposed C3H/HeN mice. Pretreatment with aurothioglucose (ATG), a thioredoxin reductase (TrxR) inhibitor, exacerbated the effects of hyperoxia on lung injury in a1Neu mice (11.6 +/- 0.8, P < 0.001), but attenuated hyperoxic lung edema and inflammation in C3H/HeN mice (6.3 +/- 0.4, P < 0.001). No consistent alterations were observed in lung GSH contents or liver GSH or GSSG levels after ATG pretreatment. The data suggest that modulation of Trx/TrxR systems might provide therapeutically useful alterations of cellular resistance to oxidant stresses. The protective effects of ATG against hyperoxic lung injury could prove to be particularly useful therapeutically.


Assuntos
Hiperóxia/metabolismo , Hiperóxia/patologia , Pneumopatias/metabolismo , Pneumopatias/patologia , Tiorredoxinas/metabolismo , Animais , Peso Corporal , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Fígado/enzimologia , Pulmão/enzimologia , Pulmão/patologia , Camundongos , Tamanho do Órgão , Tiorredoxina Dissulfeto Redutase/metabolismo
14.
Cell Biol Toxicol ; 22(4): 303-11, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16817014

RESUMO

N-Acetylcysteine (NAC), besides being a precursor of glutathione, has an array of other effects including an ability to scavenge free radicals, modulate gene expression and signal transduction pathways, and regulate cell survival and apoptosis. At concentrations lower than 20 mmol/L, NAC is nontoxic to cultured cells and can protect against apoptosis induced by a number of agents. A few recent reports, however, have indicated that NAC can also increase apoptosis. MK886, a 5-lipoxygenase activating protein (FLAP) inhibitor, induces apoptosis in many cell lines by an unknown mechanism that is independent of FLAP and lipoxygenase activity but is possibly related to effects on kinases such as Akt. In Jurkat T lymphocytes, NAC pretreatment (10 mmol/L) enhanced MK886-induced apoptosis by 2.4-fold. Following NAC-MK886 treatment, there was a significant increase in caspase-3 activity, and a decrease in mitochondrial transmembrane potential compared to MK886 alone. However, the extent of cytochrome c release was comparable between MK886 alone and MK886-NAC treatments. The enhancement of MK886-induced apoptosis by 10 mmol/L NAC appears to be partly related to a decrease in pH caused by this concentration of NAC, because an acidic environment favors activation of effector caspases and triggering of mitochondrial apoptosis. However, because neutralized NAC also enhanced apoptosis (1.6-fold), a direct role for NAC in augmenting the apoptotic pathways initiated by MK886 is suggested.


Assuntos
Acetilcisteína/farmacologia , Apoptose , Indóis/farmacologia , Proteínas Ativadoras de 5-Lipoxigenase , Anexina A5/farmacologia , Proteínas de Transporte/metabolismo , Caspase 3/metabolismo , Citocromos c/metabolismo , Relação Dose-Resposta a Droga , Ativação Enzimática , Fluoresceína-5-Isotiocianato/farmacologia , Sequestradores de Radicais Livres/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Células Jurkat , Proteínas de Membrana/metabolismo , Propídio/farmacologia
15.
Lung Cancer ; 52(1): 117-24, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16497409

RESUMO

Lung cancer is one of the most common causes of cancer death worldwide. Although recent advances in chemotherapy and radiation therapy have yielded modest improvements in patient outcomes, overall survival remains poor. Therefore, new therapeutic targets are needed. Phosphoinositide-dependent kinase-1 (PDK1) is one potential target. The aim of the present studies was to investigate the potential of a celecoxib-derived PDK1 inhibitor (OSU03013), that does not inhibit cyclooxygenase-2, to kill lung cancer cells in vitro. Using human non-small-cell lung cancer A549 cells, OSU03013 dose-dependently induced apoptosis. After 6 h of treatment with 7.5 microM OSU03013, 26% of the cells were apoptotic, compared to 4% of the control cells as determined by measuring the sub-G1 peak of propidium iodide stained cells with flow cytometry. A similar increase in apoptosis was evident using the Cell Death ELISA assay. OSU03013-induced apoptosis was accompanied by a reduction in the mitochondrial membrane potential, the release of cytochrome c and the cleavage of caspase-3. Surprisingly, the phosphorylation of Akt at serine 473 was increased in A549 cells treated with 7.5 microM OSU03013. However, the toxicity of OSU03013 was reduced in A549 cells expressing a constitutively active form of Akt. These data demonstrate that OSU03013 induces apoptosis in A549 cells via the mitochondrial pathway. Inhibition of the Akt pathway appears uninvolved in this toxicity, although Akt can provide protection. These results also suggest the potential of celecoxib-derived agents to treat some forms of lung cancer.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Inibidores de Ciclo-Oxigenase 2/toxicidade , Neoplasias Pulmonares/tratamento farmacológico , Pirazóis/toxicidade , Sulfonamidas/toxicidade , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Caspase 3 , Caspases/metabolismo , Celecoxib , Ciclo-Oxigenase 2/metabolismo , Citocromos c/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas
16.
Toxicol Appl Pharmacol ; 214(3): 230-6, 2006 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16473382

RESUMO

Nordihydroguaiaretic acid (NDGA), a general lipoxygenase (LOX) enzyme inhibitor, induces apoptosis independently of its activity as a LOX inhibitor in murine pro-B lymphocytes (FL.12 cells) by a mechanism that is still not fully understood. Glutathione depletion, oxidative processes and mitochondrial depolarization appear to contribute to the apoptosis induced by NDGA. The current data demonstrate that NDGA (20 microM)-induced apoptosis in FL5.12 cells is partially protected by N-acetylcysteine (NAC) (10 mM) and dithiothreitol (DTT) (500 microM) pretreatment, confirming a role for oxidative processes. In addition, the treatment of FL5.12 cells with NDGA led to an increase in phosphorylation and activation of the MAP kinases ERK, JNK and p38. Although pretreatment with ERK inhibitors (PD98059 or U0126) abolished ERK phosphorylation in response to NDGA, neither inhibitor had any effect on NDGA-induced apoptosis. SP600125, a JNK inhibitor, did not have any effect on NDGA-induced phosphorylation of JNK nor apoptosis. Pretreatment with the p38 inhibitor SB202190 attenuated NDGA-induced apoptosis by 30% and also abolished p38 phosphorylation, compared to NDGA treatment alone. NAC, but not DTT, also decreased the phosphorylation of p38 and JNK supporting a role for oxidative processes in activating these kinases. Neither NAC nor DTT blocked the phosphorylation of ERK suggesting that this activation is not related to oxidative stress. The release of cytochrome c and activation of caspase-3 induced by NDGA were inhibited by NAC. SB202190 slightly attenuated caspase-3 activation and had no effect on the release of cytochrome c. These data suggest that several independent mechanisms, including oxidative reactions, activation of p38 kinase and cytochrome c release contribute to NDGA-induced apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Linfócitos B/efeitos dos fármacos , Inibidores de Lipoxigenase/farmacologia , Masoprocol/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Acetilcisteína/farmacologia , Animais , Linfócitos B/enzimologia , Linfócitos B/metabolismo , Caspase 3 , Caspases/metabolismo , Linhagem Celular , Citocromos c/metabolismo , Ditiotreitol/farmacologia , Eletroforese em Gel de Poliacrilamida , Inibidores Enzimáticos/farmacologia , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação
17.
Biochem J ; 391(Pt 2): 441-8, 2005 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-16060857

RESUMO

NGAL (human neutrophil gelatinase-associated lipocalin) and its mouse analogue 24p3 are members of the lipocalin family of small secreted proteins. These proteins are up-regulated in a number of pathological conditions, including cancers, and may function as transporters of essential factors. Although previous publications have suggested that 24p3 has pro-apoptotic functions, other data are more suggestive of a survival function. The current study was designed to determine whether NGAL is pro- or anti-apoptotic. Apoptosis induced in human adenocarcinoma A549 cells by the 5-lipoxygenase-activating-protein inhibitor MK886, or several celecoxib-derived PDK1 (phosphoinositide-dependent kinase 1) inhibitors that are devoid of cyclo-oxygenase-2 inhibitory activity, was accompanied by a dose- and time-dependent increase of NGAL mRNA levels, as was reported previously with 24p3. A similar induction of NGAL mRNA was observed in human breast cancer MCF7 cells treated with MK886, indicating this was not a cell-specific effect. Treatment of A549 cells with up to 150 mug/10(6) cells of purified recombinant NGAL protein had no effect on viability, whereas antisera against the full-length NGAL protein induced apoptosis in these cells. The stable overexpression of NGAL in A549 cells had no effect on proliferation or viability. However, the cell death induced by a PDK1 inhibitor was reduced by 50% in NGAL-overexpressing cells. Decreasing NGAL mRNA and protein expression with siRNA (small interfering RNA) in A549 cells increased the toxicity of a PDK1 inhibitor by approx. 45%. These data indicate that, although the induction of NGAL correlates with apoptosis, this induction represents a survival response. Because NGAL is a secreted protein, it may play an extracellular role in cell defence against toxicants and/or facilitate the survival of the remaining cells.


Assuntos
Proteínas de Fase Aguda/metabolismo , Apoptose , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Quinases Dependentes de 3-Fosfoinositídeo , Proteínas de Fase Aguda/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Indóis/farmacologia , Lipocalina-2 , Lipocalinas , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , Pirazóis/farmacologia , Pirazóis/toxicidade , RNA Mensageiro/metabolismo , Sulfonamidas/farmacologia , Sulfonamidas/toxicidade , Regulação para Cima/efeitos dos fármacos
18.
Front Biosci ; 10: 1727-38, 2005 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15769662

RESUMO

Cellular fate is controlled by a number of factors within the cell, including an abundance of, and defenses against, free radicals generated both endogenously and exogenously. Free radical species are involved in regulating various growth, differentiation and death processes including apoptosis. Apoptosis is a preferred form of cell death because it is highly ordered resulting in the death of a cell with minimal effects on surrounding cells or tissues. Radicals generated during apoptosis directly modulate signaling cascades by activating or inhibiting survival transcription factors (i.e. NF-kappa B and AP-1), or more indirectly affecting such signaling by changing the cellular redox status [i.e. glutathione (GSH) and thioredoxin (Trx)]. At high levels, free radicals, including reactive oxygen species and various unwanted and harmful byproducts of reactions with tissue macromolecules, particularly lipids, can cause acute injury if not hindered by cellular antioxidants. These antioxidant protective systems are not only involved in preventing stress, but also maintaining the normal functioning of specific transcription factors and the bcl proteins. This review will discuss the association of reactive oxygen species with GSH, Trx and bcl proteins in apoptosis.


Assuntos
Apoptose/fisiologia , Radicais Livres/metabolismo , Glutationa/metabolismo , Tiorredoxinas/metabolismo , Ciclina D1/metabolismo , Ácidos Graxos/metabolismo , Humanos , Oxirredução , Fatores de Transcrição/metabolismo
19.
Toxicology ; 204(2-3): 209-18, 2004 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-15388247

RESUMO

Acrolein is a widespread environmental pollutant that reacts rapidly with nucleophiles, especially cellular thiols. In addition to glutathione (GSH), thioredoxin (Trx) and thioredoxin reductase (TR) contain thiol groups and may react with electrophiles. In the present study, A549 cells treated with 5-25 microM acrolein for 30 min lost cellular Trx activity in a dose-dependent fashion. Over 90% of Trx activity was lost at concentrations of 25 microM or greater. In contrast, Trx protein content, as assessed by western blotting, was not altered immediately after the 30 min acrolein treatment. Both Trx activity and protein levels increased 4h after the acrolein treatment. However, Trx activity remained below control levels at 24h. A similar dose-response relationship was seen with TR in A549 cells exposed to acrolein. There was, however, a rapid recovery of TR activity such that it attained normal levels by 4h after doses < or = 75 microM acrolein. Diethyl maleate (DEM), a common but not highly specific, agent used to deplete GSH, also inactivated Trx. A 2 h exposure of A549 cells to 1 mM DEM depleted cellular GSH by ~50% and diminished Trx activity by over 67%. Lower DEM doses (0.125 mM and 0.25 mM) for 1h had no significant effect on GSH but significantly decreased Trx activity 12 and 23%, respectively. Similar to immediately after acrolein exposure, DEM did not affect Trx protein levels. A Trx-1-GFP fusion protein was transfected into A549 cells. While the fusion protein was expressed, the Trx component was inactive by the insulin reducing assay. In summary, Trx and TR are inactivated by acrolein. In addition, the GSH depleting agent DEM inactivates Trx somewhat more effectively than it depletes GSH. The Trx-1-GFP fusion protein, while readily expressed, appears to have little or no activity, perhaps because the small size of Trx-1 (12 kDa) is affected by the larger GFP.


Assuntos
Acroleína/metabolismo , Glutationa/metabolismo , Maleatos/farmacologia , Tiorredoxinas/antagonistas & inibidores , Tiorredoxinas/metabolismo , Acroleína/farmacologia , Sítios de Ligação/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos
20.
Free Radic Biol Med ; 37(1): 36-47, 2004 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15183193

RESUMO

Ligands of peroxisome proliferator-activated receptors (PPARs) come from a diverse group of chemicals that include pharmaceutical drugs, phthalate plasticizers, steroids, and pesticides. PPAR ligands exhibit a number of effects, including an ability to induce apoptosis in some systems. The mechanism(s) underlying the induction of apoptosis is not known. The current study examined the ability of Wy14643, a fibrate and PPARalpha agonist, and ciglitazone, a thiazolidinedione and PPARgamma agonist, to induce apoptosis as well as the production of oxidants in human Jurkat T cells that express all PPAR isoforms. Treatment with increasing doses of Wy14643 caused a substantial time-dependent increase in the overall oxidant status (as reflected by increased dichlorofluorescein fluorescence) of Jurkat cells without any change in viability except at the highest dose and longest time. Ciglitazone also caused a dose- and time-dependent increase in oxidant production. However, although the extent of this production was less than that seen with Wy14643, ciglitazone caused a dose- and time-dependent increase in apoptosis that could not be inhibited by antioxidants. Confocal micrographs of Jurkat cells loaded with dichlorofluorescein diacetate or dihydrorhodamine 123 and treated with Wy14643 or ciglitazone revealed a punctate pattern of fluorescence at early time points suggestive of a mitochondrial origin for these oxidants. Rotenone and antimycin A prevented Wy14643- but not ciglitazone-induced oxidant production. Other relatively specific PPARgamma agonists (15delta-PGJ2, and troglitazone), but not nonspecific agonists (bezafibrate and conjugated linoleic acid), were also able to induce oxidant production in Jurkat cells. These data, as well as the findings that oxidant production could be induced by Wy14643 in A549 cells that lack PPARalpha, and could not be blocked in Jurkat cells by the PPARalpha inhibitor MK886, indicate oxidant formation is unrelated to PPARalpha. These data also suggest that oxidant production induced by PPARalpha ligands originates in the mitochondria.


Assuntos
Morte Celular/fisiologia , Oxidantes/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/fisiologia , Adenocarcinoma , Apoptose/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Hipoglicemiantes/farmacologia , Células Jurkat , Ligantes , Proliferadores de Peroxissomos/farmacologia , Pirimidinas/farmacologia , Tiazolidinedionas/farmacologia
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