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1.
Bioconjug Chem ; 28(2): 461-470, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27997127

RESUMO

A new targeting chemotherapeutic agent, Pt-Mal-LHRH, was synthesized by linking activated cisplatin to luteinizing hormone releasing hormone (LHRH). The compound's efficacy and selectivity toward 4T1 breast cancer cells were evaluated. Carboplatin was selected as the comparative platinum complex, since the Pt-Mal-LHRH malonate linker chelates platinum in a similar manner to carboplatin. Breast cancer and normal cell viability were analyzed by an MTT assay comparing Pt-Mal-LHRH with carboplatin. Cells were also treated with either Pt-Mal-LHRH or carboplatin to evaluate platinum uptake by ICP-MS and cell migration using an in vitro scratch-migration assay. Tumor volume and metastasis were evaluated using an in vivo 4T1 mouse tumor model. Mice were administered Pt-Mal-LHRH (carboplatin molar equivalent dosage) through ip injection and compared to those treated with carboplatin (5 (mg/kg)/week), no treatment, and LHRH plus carboplatin (unbound) controls. An MTT assay showed a reduction in cell viability (p < 0.01) in 4T1 and MDA-MB-231 breast cancer cells treated with Pt-Mal-LHRH compared to carboplatin. Pt-Mal-LHRH was confirmed to be cytotoxic by flow cytometry using a propidium iodide stain. Pt-Mal-LHRH displayed a 20-fold increase in 4T1 cellular uptake compared to carboplatin. There was a decrease (p < 0.0001) in 4T1 cell viability compared to 3T3 normal fibroblast cells. Treatment with Pt-Mal-LHRH also resulted in a significant decrease in cell-migration compared to carboplatin. In vivo testing found a significant reduction in tumor volume (p < 0.05) and metastatic tumor colonization in the lungs with Pt-Mal-LHRH compared to carboplatin. There was a slight decrease in lung weight and no difference in liver weight between treatment groups. Together, our data indicate that Pt-Mal-LHRH is a more potent and selective chemotherapeutic agent than untargeted carboplatin.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Mama/efeitos dos fármacos , Cisplatino/uso terapêutico , Sistemas de Liberação de Medicamentos , Hormônio Liberador de Gonadotropina/uso terapêutico , Receptores LHRH/metabolismo , Células 3T3 , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/farmacocinética , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Cisplatino/administração & dosagem , Cisplatino/química , Cisplatino/farmacocinética , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/química , Hormônio Liberador de Gonadotropina/farmacocinética , Humanos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Endogâmicos BALB C , Regulação para Cima/efeitos dos fármacos
2.
Am J Physiol Heart Circ Physiol ; 305(1): H104-13, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23604714

RESUMO

Recent data revealed that protein kinase C-potentiated myosin phosphatase inhibitor of 17 kDa (CPI-17), a myosin phosphatase inhibitory protein preferentially expressed in smooth muscle, is upregulated/activated in several diseases but whether this CPI-17 increase plays a causal role in pathologically enhanced vascular smooth muscle contractility and blood pressure remains unclear. To address this possibility, we generated a smooth muscle-specific CPI-17 transgenic mouse model (CPI-17-Tg) and demonstrated that the CPI-17 transgene was selectively expressed in smooth muscle-enriched tissues, including mesenteric arteries. The isometric contractions in the isolated second-order branch of mesenteric artery helical strips from CPI-17-Tg mice were significantly enhanced compared with controls in response to phenylephrine, U-46619, serotonin, ANG II, high potassium, and calcium. The perfusion pressure increases in isolated perfused mesenteric vascular beds in response to norepinephrine were also enhanced in CPI-17-Tg mice. The hypercontractility was associated with increased phosphorylation of CPI-17 and 20-kDa myosin light chain under basal and stimulated conditions. Surprisingly, the protein levels of rho kinase 2 and protein kinase Cα/δ were significantly increased in CPI-17-Tg mouse mesenteric arteries. Radiotelemetry measurements demonstrated that blood pressure was significantly increased in CPI-17-Tg mice. However, no vascular remodeling was detected by morphometric analysis. Taken together, our results demonstrate that increased CPI-17 expression in smooth muscle promotes vascular smooth muscle contractility and increases blood pressure, implicating a pathological significant role of CPI-17 upregulation.


Assuntos
Pressão Sanguínea , Contração Isométrica/genética , Proteínas Musculares/metabolismo , Músculo Liso Vascular/fisiologia , Fosfoproteínas/metabolismo , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Angiotensina II/farmacologia , Animais , Cálcio/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular , Contração Isométrica/efeitos dos fármacos , Artérias Mesentéricas/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Musculares/genética , Músculo Liso Vascular/metabolismo , Fenilefrina/farmacologia , Fosfoproteínas/genética , Potássio/farmacologia , Serotonina/farmacologia , Transcrição Gênica , Regulação para Cima , Vasoconstritores/farmacologia
3.
ACS Omega ; 6(3): 1846-1856, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33521425

RESUMO

Currently, 186/188Re and 99mTc are widely used radionuclides for cancer detection and diagnosis. New advancements in modalities and targeting strategies of radiopharmaceuticals will provide an opportunity to enhance imagery and detection of smaller colonies of cancer cells while lowering false-positive diagnoses. To understand the chemistry of agents derived from fac-[99mTc(CO)3(H2O)3]+ species, the nonradioactive [Re(CO)3(H2O)3]+ analogue was used. We have designed and synthesized Re-Acdien-LHRH, Re-Acdien-peg-LHRH, and a radiolabeled 99mTc-Acdien-LHRH (rhenium- and technetium-luteinizing hormone-releasing hormone) conjugates using a tridentate linker to detect cancers overexpressing the LHRH receptor. Re-Acdien-LHRH and Re-Acdien-peg-LHRH were synthesized from non-PEGylated and PEGylated LHRH-Acdien, respectively. Cellular uptake of the compounds 99mTc-Acdien-LHRH, Re-Acdien-LHRH, and Re-Acdien-peg-LHRH was found to be significantly enhanced compared to that of untargeted 99mTc alone and unlabeled [Re(CO)3(H2O)3]+. In addition, the conjugate compounds showed no difference in cellular toxicity compared to untargeted 99mTc alone or unlabeled [Re(CO)3(H2O)3]+. Further, a competition assay using LHRH indicated selective targeting of Re-Acdien-peg-LHRH toward the LHRH receptor (p < 0.05) compared to that of [Re(CO)3(H2O)3]+ alone. Together, our data show the design paradigm and synthesis of targeting radionuclides using the LHRH peptide. Our data suggests that utilizing the LHRH peptide can lead to selective targeting and diagnosis of breast cancers expressing the LHRH receptor.

4.
Patient Relat Outcome Meas ; 10: 205-208, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308772

RESUMO

INTRODUCTION: A review of the medical device adverse events submitted to the United States Food & Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE) database was undertaken to determine the major sources of the information. METHODS: The reporter's occupation and source of the medical device report were determined for acquisition dates Jan 1, 1997 to Dec 31, 2018. A total of 7,766,737 adverse event records were analyzed. RESULTS: 96.6% of reports originated with the manufacturer. Patients (patients/family/friend) were the most frequent submitter of reports directly to the FDA, almost five times as often as physicians. Nurses submitted reports directly to the FDA 2.77 times as often as physicians. Only 0.49% of physician reports were submitted directly to the FDA, representing 0.09% of total MAUDE reports. CONCLUSION: Increasing physician reporting directly to the FDA and MAUDE through the MedWatch reporting system is an imperative. Incorporating information from the perspective of the physician has the potential of increasing the quality of the data and improving the reliability of post-market surveillance.

5.
Artigo em Inglês | MEDLINE | ID: mdl-30250734

RESUMO

The authors advocate the addition of two preventative strategies to the current United State's guidelines for the prevention of surgical site infections. It is known that Staphylococcus aureus, including Methicillin-resistant Staphylococcus aureus (MRSA), carriers are at a higher risk for the development of infections and they can easily transmit the organism. The carriage rate of Staph. aureus in the general population approximates 33%. The CDC estimates the carriage rate of MRSA in the United States is approximately 2%. The first strategy is preoperative screening of surgical patients for Staph. aureus, including MRSA. This recommendation is based upon the growing literature which shows a benefit in both prevention of infections and guidance in preoperative antibiotic selection. The second is performing MRSA active surveillance screening on healthcare workers. The carriage rate of MRSA in healthcare workers approximates 5% and there are concerns of transmission of this pathogen to patients. MRSA decolonization of healthcare workers has been reported to approach a success rate of 90%. Healthcare workers colonized with dangerous pathogens, including MRSA, should be assigned to non-patient contact work areas. In addition, there needs to be implemented a safety net for both the worker's economic security and healthcare. Finally, a reporting system for the healthcare worker acquisition and infections with dangerous pathogens needs to be implemented. These recommendations are needed because Staph. aureus including MRSA is endemic in the United States. Policies regarding endemic pathogens which are to be implemented only upon the occurrence of a facility defined "outbreak" have to be questioned, since absence of infections does not mean absence of transmission. Optimizing these policies will require further research but until then we should error on the side of patient safety.


Assuntos
Infecção Hospitalar , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/prevenção & controle , Infecção da Ferida Cirúrgica/microbiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Surtos de Doenças , Desinfecção , Pessoal de Saúde , Diretrizes para o Planejamento em Saúde , Política de Saúde , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Guias de Prática Clínica como Assunto , Infecções Estafilocócicas/transmissão , Infecção da Ferida Cirúrgica/transmissão , Estados Unidos/epidemiologia
6.
Artigo em Inglês | MEDLINE | ID: mdl-28396730

RESUMO

A review of epidemiological studies on the incidence of MRSA infections overtime was performed along with an analysis of data available for download from Hospital Compare (https://data.medicare.gov/data/hospital-compare). We found the estimations of the incidence of MRSA infections varied widely depending upon the type of population studied, the types of infections captured and in the definitions and terminology used to describe the results. We could not find definitive evidence that the incidence of MRSA infections in U.S. community or facilities is decreasing significantly. Of concern are recent data reported to the National Healthcare Safety Network (NHSN) on MRSA bloodstream infections which indicate that by the end of 2015 there had been little change in the average facility Standardized Infection Ratio (0.988), compared to a 2010-2011 baseline and is significantly increased compared to the previous year. This is in contradistinction to the recent Veterans Administration study which reported over an 80% reduction in MRSA infections. However, this discrepancy may be due to the inability to reconcile the baselines of the two data sets; and the observed increase may be artifactual due to aberrations in the NHSN tracking system. Our review supports the need for implementation of a comprehensive tracking and monitoring system involving all types of healthcare facilities for multi-drug resistant organisms, along with concomitant funding for both staff and infrastructure. Without such a system, determining the effectiveness of interventions such as antibiotic stewardship and chlorhexidine bathing will be hindered.

7.
J Evid Inf Soc Work ; 13(2): 198-205, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25844672

RESUMO

In this study the authors investigate the sound pressure levels produced by crying children and discuss the possible adverse effects that direct exposure may impose on a tending guardian or healthcare professional. Sound intensity levels from various pediatric patients (N = 26) were measured under two segregate conditions, one imitating the exposure of an examining physician and the other resembling that of parental guardians. Interestingly, all of the recorded sound levels fell between 99-120 dB(A) of sound pressure; children presenting the greatest risk for intense cries with potentially harmful sound intensities were between the ages of 9 months and 6 years. The authors found that elevated noise levels produced from crying children can cause acute discomfort and mild pain to those exposed. In addition, there is a theoretical risk that chronic exposure to these intense sound pressures may result in noise-induced hearing loss in a parental guardian or an examining physician. Parents of young children may be more likely to succumb to impulsive reactions in attempting to arrest the crying, which could be a precipitating factor for child abuse, responding to physical stress as much as emotional stress. Social workers and medical personnel should consider suggesting the use of ear plugs by parental guardians of frequently crying children as a modality for the prevention of child abuse.


Assuntos
Choro/psicologia , Pessoal de Saúde/psicologia , Perda Auditiva Provocada por Ruído/epidemiologia , Pais/psicologia , Criança , Maus-Tratos Infantis/psicologia , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Espectrografia do Som
8.
Am J Infect Control ; 43(10): 1050-2, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26139001

RESUMO

Catheter-associated urinary tract infections (CAUTIs) occur in 290,000 US hospital patients annually, with an estimated cost of $290 million. Two different measurement systems are being used to track the US health care system's performance in lowering the rate of CAUTIs. Since 2010, the Agency for Healthcare Research and Quality (AHRQ) metric has shown a 28.2% decrease in CAUTI, whereas the Centers for Disease Control and Prevention metric has shown a 3%-6% increase in CAUTI since 2009. Differences in data acquisition and the definition of the denominator may explain this discrepancy. The AHRQ metric analyzes chart-audited data and reflects both catheter use and care. The Centers for Disease Control and Prevention metric analyzes self-reported data and primarily reflects catheter care. Because analysis of the AHRQ metric showed a progressive change in performance over time and the scientific literature supports the importance of catheter use in the prevention of CAUTI, it is suggested that risk-adjusted catheter-use data be incorporated into metrics that are used for determining facility performance and for value-based purchasing initiatives.


Assuntos
Infecções Relacionadas a Cateter/economia , Infecções Relacionadas a Cateter/epidemiologia , Pesquisa sobre Serviços de Saúde , Controle de Infecções/métodos , Infecções Urinárias/economia , Infecções Urinárias/epidemiologia , Aquisição Baseada em Valor , Humanos , Incidência , Estados Unidos
9.
Artigo em Inglês | MEDLINE | ID: mdl-25729571

RESUMO

Surveillance and isolation for the prevention of methicillin-resistant Staphylococcus aureus (MRSA) has become a controversial topic, one that causes heated debate and appears to be surrounded by both politics and industrial conflicts-of-interest. There have been calls from numerous authors for a movement away from rigid mandates and toward an evidence-based medicine approach. However, much of the evidence can be viewed with an entirely different interpretation. Two major studies with negative findings have had an adverse impact on recommendations regarding active detection and isolation (ADI) for MRSA. However the negative findings in these studies can be explained by shortcomings in study implementation rather than the ineffectiveness of ADI. The use of daily chlorhexidine bathing has also been proposed as an alternative to ADI in ICU settings. There are shortcomings regarding the evidence in the literature concerning the effectiveness of daily chlorhexidine bathing. One of the major concerns with universal daily chlorhexidine bathing is the development of bacterial resistance. The use of surveillance and isolation to address epidemics and common dangerous pathogens should solely depend upon surveillance and isolation's ability to prevent further spread to and infection of other patients through indirect contact. At present, there is a preponderance of evidence in the literature to support continuing use of surveillance and isolation to prevent the spread of MRSA.

10.
PLoS One ; 10(11): e0143277, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26588686

RESUMO

OBJECTIVES: Calcium independent group VIA phospholipase A2 (iPLA2ß) and Matrix Metalloproteinase-9 (MMP-9) are upregulated in many disease states; their involvement with cancer cell migration has been a recent subject for study. Further, the molecular mechanisms mediating nicotine-induced breast cancer cell progression have not been fully investigated. This study aims to investigate whether iPLA2ß mediates nicotine-induced breast cancer cell proliferation and migration through both in-vitro and in-vivo techniques. Subsequently, the ability of Bromoenol Lactone (BEL) to attenuate the severity of nicotine-induced breast cancer was examined. METHOD AND RESULTS: We found that BEL significantly attenuated both basal and nicotine-induced 4T1 breast cancer cell proliferation, via an MTT proliferation assay. Breast cancer cell migration was examined by both a scratch and transwell assay, in which, BEL was found to significantly decrease both basal and nicotine-induced migration. Additionally, nicotine-induced MMP-9 expression was found to be mediated in an iPLA2ß dependent manner. These results suggest that iPLA2ß plays a critical role in mediating both basal and nicotine-induced breast cancer cell proliferation and migration in-vitro. In an in-vivo mouse breast cancer model, BEL treatment was found to significantly reduce both basal (p<0.05) and nicotine-induced tumor growth (p<0.01). Immunohistochemical analysis showed BEL decreased nicotine-induced MMP-9, HIF-1alpha, and CD31 tumor tissue expression. Subsequently, BEL was observed to reduce nicotine-induced lung metastasis. CONCLUSION: The present study indicates that nicotine-induced migration is mediated by MMP-9 production in an iPLA2ß dependent manner. Our data suggests that BEL is a possible chemotherapeutic agent as it was found to reduce both nicotine-induced breast cancer tumor growth and lung metastasis.


Assuntos
Anticarcinógenos/farmacologia , Carcinógenos/antagonistas & inibidores , Neoplasias Pulmonares/prevenção & controle , Neoplasias Mamárias Experimentais/tratamento farmacológico , Naftalenos/farmacologia , Nicotina/antagonistas & inibidores , Pironas/farmacologia , Animais , Carcinógenos/toxicidade , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Fosfolipases A2 do Grupo VI/genética , Fosfolipases A2 do Grupo VI/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Nicotina/toxicidade , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Transdução de Sinais , Ativação Transcricional , Ensaios Antitumorais Modelo de Xenoenxerto
11.
J Patient Saf ; 10(4): 222-30, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24104483

RESUMO

INTRODUCTION: The hidden cost of defensive medicine has been cited by policymakers as a significant driving force in the increase of our nation's health-care costs. If this hypothesis is correct, one would expect that states with higher levels of tort reform will have a decrease in Medicare utilization and that medical utilization will decrease after tort reform is enacted. METHODS: State-level reimbursement data for years 1999 to 2010 (the last year available) was obtained from the Dartmouth Atlas of Health Care. Medical tort rankings for the 50 states were obtained from the Pacific Research Institute (PRI) and correlated with state medical utilization for the year 2010. In 3 states, Mississippi, Nevada, and Texas, data were available to make pretort and posttort reform comparisons. RESULTS: Data analysis between total state Medicare Reimbursements and the PRI's tort rankings showed no significant observed correlation. In 6 Medicare utilization categories (total Medicare, hospital and skilled nursing facility, physician, home health agency, hospice, and durable medical equipment), a negative trend was observed when correlated with PRI tort rankings. This trend does not support the hypothesis that defensive medicine is a major driver of health-care expenditures. Tracking expenditures in the states of Texas, Nevada, and Mississippi, before and after passage of comprehensive medical tort reform gave inconsistent results and did not demonstrate substantial or meaningful total Medicare savings. In Mississippi, there was a trend of decreased expenditures after medical tort reform was passed. However, in Texas, where 80% of the analyzed enrollees resided, there was a trend of progressive increasing expenditures after tort reform was passed. CONCLUSION: The comparison of the Dartmouth Atlas Medicare Reimbursement Data with Malpractice Reform State Rankings, which are used by the PRI, did not support the hypothesis that defensive medicine is a driver of rising health-care costs. Additionally, comparing Medicare reimbursements, premedical and postmedical tort reform, we found no consistent effect on health-care expenditures. Together, these data indicate that medical tort reform seems to have little to no effect on overall Medicare cost savings.


Assuntos
Atenção à Saúde , Custos de Cuidados de Saúde , Serviços de Saúde/economia , Responsabilidade Legal/economia , Imperícia/economia , Medicare , Atenção à Saúde/economia , Atenção à Saúde/legislação & jurisprudência , Serviços de Saúde/estatística & dados numéricos , Humanos , Estados Unidos
12.
Artigo em Inglês | MEDLINE | ID: mdl-24847437

RESUMO

The Agency for Healthcare Research & Quality (AHRQ) found that Methicillin-resistant Staphylococcus aureus (MRSA) is associated with up to 375,000 infections and 23,000 deaths in the United States. It is a major cause of surgical site infections, with a higher mortality and longer duration of care than Methicillin-sensitive Staphylococcus aureus. A multifactorial bundled approach is needed to control this epidemic, with single interventions unlikely to have a significant impact on attenuating MRSA infection rates. Active surveillance has been studied in a wide range of surgical patients, including surgical intensive care and non-intensive care units; cardiac, vascular, orthopedic, obstetric, head and neck cancer and gastrostomy patients. There is sufficient evidence demonstrating a beneficial effect of surveillance and eradication prior to surgery to recommend its use on an expanded basis. Studies on MRSA surveillance in surgical patients that were published over the last 10 years were reviewed. In at least five of these studies, the MRSA colonization status of patients was reported to be a factor in preoperative antibiotic selection, with the modification of treatment regiments including the switching to vancomycin or teicoplanin in MRSA positive preoperative patients. Several authors also used decolonization protocols on all preoperative patients but used surveillance to determine the duration of the decolonization. Universal decolonization of all patients, regardless of MRSA status has been advocated as an alternative prevention protocol in which surveillance is not utilized. Concern exists regarding antimicrobial stewardship. The daily and universal use of intranasal antibiotics and/or antiseptic washes may encourage the promotion of bacterial resistance and provide a competitive advantage to other more lethal organisms. Decolonization protocols which indiscriminately neutralize all bacteria may not be the best approach. If a patient's microbiome is markedly challenged with antimicrobials, rebuilding it with replacement commensal bacteria may become a future therapy. Preoperative MRSA surveillance allows the selection of appropriate prophylactic antibiotics, the use of extended decolonization protocols in positive patients, and provides needed data for epidemiological studies.

13.
PLoS One ; 7(2): e31850, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22363752

RESUMO

OBJECTIVES: Calcium independent group VIA phospholipase A(2) (iPLA(2)ß) is up-regulated in vascular smooth muscle cells in some diseases, but whether the up-regulated iPLA(2)ß affects vascular morphology and blood pressure is unknown. The current study addresses this question by evaluating the basal- and angiotensin II infusion-induced vascular remodeling and hypertension in smooth muscle specific iPLA(2)ß transgenic (iPLA(2)ß-Tg) mice. METHOD AND RESULTS: Blood pressure was monitored by radiotelemetry and vascular remodeling was assessed by morphologic analysis. We found that the angiotensin II-induced increase in diastolic pressure was significantly higher in iPLA(2)ß-Tg than iPLA(2)ß-Wt mice, whereas, the basal blood pressure was not significantly different. The media thickness and media∶lumen ratio of the mesenteric arteries were significantly increased in angiotensin II-infused iPLA(2)ß-Tg mice. Analysis revealed no difference in vascular smooth muscle cell proliferation. In contrast, adenovirus-mediated iPLA(2)ß overexpression in cultured vascular smooth muscle cells promoted angiotensin II-induced [(3)H]-leucine incorporation, indicating enhanced hypertrophy. Moreover, angiotensin II infusion-induced c-Jun phosphorylation in vascular smooth muscle cells overexpressing iPLA2ß to higher levels, which was abolished by inhibition of 12/15 lipoxygenase. In addition, we found that angiotensin II up-regulated the endogenous iPLA(2)ß protein in-vitro and in-vivo. CONCLUSION: The present study reports that iPLA(2)ß up-regulation exacerbates angiotensin II-induced vascular smooth muscle cell hypertrophy, vascular remodeling and hypertension via the 12/15 lipoxygenase and c-Jun pathways.


Assuntos
Angiotensina II/farmacologia , Fosfolipases A2 do Grupo VI/metabolismo , Hipertensão/enzimologia , Hipertensão/fisiopatologia , Músculo Liso Vascular/enzimologia , Músculo Liso Vascular/fisiopatologia , Angiotensina II/administração & dosagem , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/fisiopatologia , Araquidonato 15-Lipoxigenase , Ácido Araquidônico/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Diástole/efeitos dos fármacos , Hipertensão/patologia , Hipertrofia , Leucina/metabolismo , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/enzimologia , Miócitos de Músculo Liso/patologia , Especificidade de Órgãos/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-jun/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
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