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1.
Acad Med ; 97(7): 938, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35767397
2.
Acad Med ; 96(6): 817-821, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33637663

RESUMO

Advancing equity for women remains an urgent and complex problem at academic health centers. Attempts to mitigate gender gaps have ranged widely and have been both slow to occur and limited in effect. Recognizing the limitations of previously attempted solutions and fueled by the #MeToo and #TimesUp movements, the Medical College of Wisconsin (MCW) stepped outside known approaches (e.g., women's leadership plans and programming) to design and implement a strategic campaign that promotes gender equity through fostering change in systems and social norms. This campaign, IWill MCW (launched in 2019), emphasizes the power of individual responsibility for positive change. The IWill MCW campaign employs a 2-pronged approach. The first is the creation of personal call-to-action public pledges focused on 5 aspects of gender equity, along with the provision of supportive resources to reinforce positive change. The second is the use of those pledges to raise awareness of gender inequity in academic medicine by fostering meaningful dialogue meant to alter mental models of equity, relationships, and power dynamics. In the initial 6-week phase of the IWill MCW campaign, leaders reached out to all MCW faculty (2,002), staff (4,522), and learners (1,483) at multiple campuses. This outreach resulted in nearly 1,400 pledges, including 30% (n = 420) from men. The effort also engaged over 90% (n = 101) of members of MCW senior leadership teams. The feedback from the initial campaign has been positive. Lessons learned include realizing the importance of public pledges, engaging male allies, and following up. The authors suggest that the IWill MCW campaign provides a model for academic health centers to advance gender equity and shape an environment in which people of all genders can thrive.


Assuntos
Centros Médicos Acadêmicos/organização & administração , Equidade de Gênero , Médicas , Faculdades de Medicina/organização & administração , Sexismo/prevenção & controle , Feminino , Humanos , Liderança , Masculino , Responsabilidade Social , Wisconsin
3.
Health Aff (Millwood) ; 39(11): 1926-1934, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33136498

RESUMO

This study aimed to understand racial/ethnic differences in coronavirus disease 2019 (COVID-19) screening, symptom presentation, hospitalization, and mortality, using data from 31,549 adults tested for COVID-19 between March 1 and July 10, 2020, in Milwaukee and Southeast Wisconsin. Racial/ethnic differences existed in adults who screened positive for COVID-19 (4.5 percent of non-Hispanic Whites, 14.9 percent of non-Hispanic Blacks, and 14.8 percent of Hispanics). After adjustment for demographics and comorbidities, Blacks and Hispanics were more than three times more likely to screen positive and two times more likely to be hospitalized relative to Whites, and Hispanics were two times more likely to die than Whites. Given the long-standing history of structural racism, residential segregation, and social risk in the US and their role as contributors to poor health, we propose and discuss the part these issues play as explanatory factors for our findings.


Assuntos
Infecções por Coronavirus , Etnicidade/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Pandemias , Pneumonia Viral , Grupos Raciais , Negro ou Afro-Americano/estatística & dados numéricos , Betacoronavirus/isolamento & purificação , COVID-19 , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/terapia , Estudos Transversais , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/diagnóstico , Pneumonia Viral/mortalidade , Pneumonia Viral/terapia , SARS-CoV-2 , População Branca/estatística & dados numéricos , Wisconsin
4.
WMJ ; 119(4): 229-239, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33428832

RESUMO

BACKGROUND: Despite a rapidly growing and evolving literature, there continues to be a vigorous public debate about whether the community use of face coverings can mitigate the spread of COVID-19 ten months into the pandemic. OBJECTIVES: This article describes a semi-structured literature review of the use of face coverings to prevent the spread of coronaviruses and similar respiratory pathogens, with a focus on SARS-CoV-2 (COVID-19). METHODS: : The author conducted a semi-structured literature review using search terms "COVID19" or "SARS-CoV-2" crossed with "mask/s" or "face covering/s." Articles were evaluated through October 30, 2020 for inclusion, as were key references cited within the primary references and other references identified through traditional and social media outlets. RESULTS: There is strong evidence to support the community use of face coverings to mitigate the spread of COVID-19 from various laboratory, epidemiological, natural history, clinical, and economic studies, although there was only 1 high-quality published randomized controlled trial of this topic at the time of review. CONCLUSIONS: The evidence in favor of community face coverings to slow the spread of COVID-19 is strong. Although most of the benefit of wearing a face covering is conferred to the community and to bystanders, a face covering also can protect the wearer to some extent, both by reducing the risk of COVID-19 infection, and perhaps by reducing the severity of illness for those who contract a COVID-19 infection.


Assuntos
COVID-19/prevenção & controle , Controle de Doenças Transmissíveis/instrumentação , Máscaras , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , COVID-19/epidemiologia , COVID-19/transmissão , Humanos , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , SARS-CoV-2
5.
Pharmacotherapy ; 39(6): 677-688, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30351459

RESUMO

In 2000, the first biphasic modified-release (MR) formulation of methylphenidate (MPH) was approved for the treatment of attention-deficit/hyperactivity disorder (ADHD). An immediate-release (IR) MPH pulse (22% of the dose) facilitates rapid onset of stimulant action, while the remaining MR portion of the dose provides for day-long duration of efficacy. A wide array of oral MR-MPH products has subsequently been approved that also allows for once-daily dosing, though each product is characterized by distinctive exposure time courses. This review compares each member of the current MPH armamentarium to assist in the rational selection of a specific MPH regimen for the individualized treatment of patients with ADHD. The IR portion of biphasic MPH formulations now ranges from 15%, 20%, 22%, 25%, 30%, and 37% IR-MPH, as well as a 50% IR-MPH product whose distinctly pulsatile time course closely resembles that of the pre-century "gold standard" twice-daily IR-MPH regimen. Further, transdermal, suspension, and orally disintegrating tablet products are now available to overcome any solid dosage form swallowing difficulties. Most of these formulations are racemic, though in 2001, a chiral switch drug IR-dexmethylphenidate (dexMPH) was approved, followed by biphasic MR-dexMPH (50% IR) in 2005. New U.S. Food and Drug Administration (FDA) partial area under the curve (pAUC) bioavailability metrics have improved discrimination between specific generic MR-MPH products. This has resulted in two Orange Book MR-MPH products being recoded from "AB" (i.e., meets necessary bioequivalence requirements) to "BX" (i.e., insufficient data to confirm bioequivalence). The metabolic drug interaction between MPH and alcohol, which increases MPH bioavailability, potentiates euphoric effects, and heightens abuse liability, is discussed. This review concludes with brief considerations of pharmacogenomic predictors of ADHD first-line drug selection, carboxylesterase allelic variants influencing interindividual MPH metabolism, and novel MPH formulations in the regulatory pipeline.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Cloridrato de Dexmetilfenidato/farmacocinética , Cloridrato de Dexmetilfenidato/uso terapêutico , Metilfenidato/farmacocinética , Metilfenidato/uso terapêutico , Medicina de Precisão/métodos , Estimulantes do Sistema Nervoso Central/farmacocinética , Estimulantes do Sistema Nervoso Central/uso terapêutico , Preparações de Ação Retardada/efeitos adversos , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/uso terapêutico , Cloridrato de Dexmetilfenidato/efeitos adversos , Formas de Dosagem , Esquema de Medicação , Humanos , Metilfenidato/efeitos adversos
7.
Trans Am Clin Climatol Assoc ; 128: 90-107, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28790490

RESUMO

In 2016, the Association of American Medical Colleges projected a physician shortage in the United States of approximately 90,000; in the same year, the Wisconsin Hospital Association projected a shortage of 2,000 physicians in Wisconsin. The Medical College of Wisconsin has begun to address these shortages in three ways: 1) creation of immersive regional medical school campuses in Green Bay and Central Wisconsin, in partnership with rural serving health systems; 2) creation of rural-based psychiatry and family medicine residency programs in Green Bay and central Wisconsin; and 3) expansion of the scope of practice of pharmacists through creation of a new School of Pharmacy in collaboration with the Medical College of Wisconsin School of Medicine. This article will discuss those approaches, history and progress to date, principles used, and future plans to address the impending physician shortages.


Assuntos
Atenção à Saúde/métodos , Educação Médica/organização & administração , Serviços de Saúde Rural/organização & administração , Faculdades de Medicina/organização & administração , Medicina de Família e Comunidade , Humanos , Internato e Residência , Modelos Educacionais , Médicos , Atenção Primária à Saúde , Wisconsin
8.
Acad Med ; 91(1): 42-7, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26445084

RESUMO

Health care conversion foundations, such as the Advancing a Healthier Wisconsin Endowment (the endowment) at the Medical College of Wisconsin (MCW), result from the conversion of nonprofit health organizations to for-profit corporations. Over the past several decades, nearly 200 of these foundations have been created, and they have had a substantial impact on the field of health philanthropy. The MCW was a recipient of funds resulting from Blue Cross & Blue Shield United of Wisconsin's conversion from a nonprofit to a for-profit status in 1999. Established in 2004, the endowment has invested approximately $185 million in 337 research, education, and public and community health initiatives that benefit Wisconsin residents. However, the transformative potential of the health care conversion foundation has extended well beyond the opportunities provided through the endowment's financial resources. As the endowment celebrates its 10th anniversary, the authors describe the transformative nature of the endowment, as well as significant accomplishments and lessons learned, in the following areas: shared power, community partnerships, translational research, and integration of medicine and public health. It is the authors' hope that these lessons will be valuable to other medical schools and the communities they serve, as they invest in improving the health of their communities, irrespective of the funding source.


Assuntos
Relações Comunidade-Instituição , Fundações , Promoção da Saúde/organização & administração , Faculdades de Medicina , Promoção da Saúde/economia , Humanos , Saúde Pública , Wisconsin
9.
Acad Med ; 91(3): 333-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26675192

RESUMO

An ombuds is an individual who informally helps people or groups (visitors) resolve disputes and/or interpersonal conflicts as an alternative to formal dispute resolution mechanisms within an organization. Ombuds are nearly ubiquitous in many governmental, business, and educational settings but only recently have gained visibility at medical schools. Medical schools in the United States are increasingly establishing ombuds offices as part of comprehensive conflict management systems to address concerns of faculty, staff, students, and others. As of 2015, more than 35 medical schools in the United States have active ombuds Web pages. Despite the growing number of medical schools with ombuds offices, the literature on medical school ombuds offices is scant. In this article, the authors review the first three years of experience of the ombuds office at the Medical College of Wisconsin, a freestanding medical and graduate school with a large physician practice. The article is written from the perspective of the inaugural ombuds and the president who initiated the office. The authors discuss the rationale for, costs of, potential advantages of, and initial reactions of faculty, staff, and administration to having an ombuds office in an academic medical center. Important questions relevant to medical schools that are considering an ombuds office are discussed. The authors conclude that an ombuds office can be a useful complement to traditional approaches for conflict management, regulatory compliance, and identification of systemic issues.


Assuntos
Centros Médicos Acadêmicos , Defesa do Consumidor , Negociação , Confidencialidade , Humanos , Wisconsin
10.
Acad Med ; 90(10): 1318-23, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26266464

RESUMO

The debate about three-year medical school curricula has resurfaced recently, driven by rising education debt burden and a predicted physician shortage. In this Perspective, the authors call for an evidence-based discussion of the merits and challenges of three-year curricula. They examine published evidence that suggests that three-year curricula are viable, including studies on three-year curricula in (1) U.S. medical schools in the 1970s and 1980s, (2) two Canadian medical schools with more than four decades of experience with such curricula, and (3) accelerated family medicine and internal medicine programs. They also briefly describe the new three-year programs that are being implemented at eight U.S. medical schools, including their own. Finally, they offer suggestions regarding how to enhance the discussion between the proponents of and those with concerns about three-year curricula.


Assuntos
Currículo , Educação de Graduação em Medicina/métodos , Medicina de Família e Comunidade/educação , Medicina Interna/educação , Faculdades de Medicina , Canadá , Educação de Graduação em Medicina/economia , Educação de Graduação em Medicina/história , Prática Clínica Baseada em Evidências , História do Século XX , História do Século XXI , Humanos , Médicos/provisão & distribuição , Fatores de Tempo , Apoio ao Desenvolvimento de Recursos Humanos , Estados Unidos
11.
PLoS One ; 10(1): e0115701, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25606852

RESUMO

The α1A-AR is thought to couple predominantly to the Gαq/PLC pathway and lead to phosphoinositide hydrolysis and calcium mobilization, although certain agonists acting at this receptor have been reported to trigger activation of arachidonic acid formation and MAPK pathways. For several G protein-coupled receptors (GPCRs) agonists can manifest a bias for activation of particular effector signaling output, i.e., not all agonists of a given GPCR generate responses through utilization of the same signaling cascade(s). Previous work with Gαq coupling-defective variants of α1A-AR, as well as a combination of Ca2+ channel blockers, uncovered cross-talk between α1A-AR and ß2-AR that leads to potentiation of a Gαq-independent signaling cascade in response to α1A-AR activation. We hypothesized that molecules exist that act as biased agonists to selectively activate this pathway. In this report, isoproterenol (Iso), typically viewed as ß-AR-selective agonist, was examined with respect to activation of α1A-AR. α1A-AR selective antagonists were used to specifically block Iso evoked signaling in different cellular backgrounds and confirm its action at α1A-AR. Iso induced signaling at α1A-AR was further interrogated by probing steps along the Gαq /PLC, Gαs and MAPK/ERK pathways. In HEK-293/EBNA cells transiently transduced with α1A-AR, and CHO_α1A-AR stable cells, Iso evoked low potency ERK activity as well as Ca2+ mobilization that could be blocked by α1A-AR selective antagonists. The kinetics of Iso induced Ca2+ transients differed from typical Gαq- mediated Ca2+ mobilization, lacking both the fast IP3R mediated response and the sustained phase of Ca2+ re-entry. Moreover, no inositol phosphate (IP) accumulation could be detected in either cell line after stimulation with Iso, but activation was accompanied by receptor internalization. Data are presented that indicate that Iso represents a novel type of α1A-AR partial agonist with signaling bias toward MAPK/ERK signaling cascade that is likely independent of coupling to Gαq.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 1/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Isoproterenol/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Receptores Adrenérgicos alfa 1/metabolismo , Animais , Células CHO , Sinalização do Cálcio/genética , Cricetulus , Subunidades alfa de Proteínas de Ligação ao GTP/genética , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Células HEK293 , Humanos , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Receptores Adrenérgicos alfa 1/genética
12.
Am J Physiol Cell Physiol ; 307(6): C554-60, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25055824

RESUMO

Epidermal growth factor (EGF) is linked to the pathogenesis of polycystic kidney disease (PKD). We explored signaling pathways activated by EGF in orpk cilia (-) collecting duct cell line derived from a mouse model of PKD (hypomorph of the Tg737/Ift88 gene) with severely stunted cilia, and in a control orpk cilia (+) cell line with normal cilia. RT-PCR demonstrated mRNAs for EGF receptor subunits ErbB1, ErbB2, ErbB3, ErbB4, and mRNAs for Na(+)/H(+) exchangers (NHE), NHE-1, NHE-2, NHE-3, NHE-4, and NHE-5 in both cell lines. EGF stimulated proton efflux in both cell lines. This effect was significantly attenuated by MIA, 5-(n-methyl-N-isobutyl) amiloride, a selective inhibitor of NHE-1 and NHE-2, and orpk cilia (-) cells were more sensitive to MIA than control cells (P < 0.01). EGF significantly induced extracellular signal-regulated kinase (ERK) phosphorylation in both cilia (+) and cilia (-) cells (63.3 and 123.6%, respectively), but the effect was more pronounced in orpk cilia (-) cells (P < 0.01). MIA significantly attenuated EGF-induced ERK phosphorylation only in orpk cilia (-) cells (P < 0.01). EGF increased proliferation of orpk cilia (+) cells and orpk cilia (-) cells, respectively, and MIA at 1-5 µM attenuated EGF-induced proliferation in orpk cilia (-) cells without affecting proliferation of orpk cilia (+) cells. EGF-induced proliferation of both cell lines was significantly decreased by the EGFR tyrosine kinase inhibitor AG1478 and MEK inhibitor PD98059. These results suggest that EGF exerts mitogenic effects in the orpk cilia (-) cells via activation of growth-associated amiloride-sensitive NHEs and ERK.


Assuntos
Proliferação de Células , Fator de Crescimento Epidérmico/metabolismo , Túbulos Renais Coletores/enzimologia , Doenças Renais Policísticas/enzimologia , Trocadores de Sódio-Hidrogênio/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cílios/enzimologia , Cílios/patologia , Modelos Animais de Doenças , Ativação Enzimática , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Receptores ErbB/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Isoenzimas , Túbulos Renais Coletores/efeitos dos fármacos , Túbulos Renais Coletores/patologia , Camundongos , Camundongos Transgênicos , Fosforilação , Doenças Renais Policísticas/genética , Doenças Renais Policísticas/patologia , Inibidores de Proteínas Quinases/farmacologia , RNA Mensageiro/metabolismo , Transdução de Sinais , Trocadores de Sódio-Hidrogênio/genética , Transfecção , Proteínas Supressoras de Tumor/genética
13.
J Ovarian Res ; 7: 6, 2014 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-24423449

RESUMO

BACKGROUND: Understanding the integration of hormone signaling and how it impacts oncogenesis is critical for improved cancer treatments. Here we elucidate GNAI2 message alterations in ovarian cancer (OvCa). GNAI2 is a heterotrimeric G protein which couples cell surface hormone receptors to intracellular enzymes, and is best characterized for its direct role in regulating cAMP response element-binding protein (CREB) function by decreasing intracellular cAMP through inhibiting adenylyl cyclase. METHODS: We probed the Origene human OvCa array for the presence of polymorphisms and gene expression alterations of GNAI2 using directing sequencing and qPCR. These data were supported by database mining of the [NCBI NIH GSE:6008, GSE:14764, GSE:29450, GDS:4066, GDS:3297, GSE:32474, and GSE:2003] datasets. RESULTS: No significant polymorphisms were found, including an absence of the gip2 oncogene. However, 85.9% of (506 of 589) OvCa patients had decreased GNAI2 message. Further characterization demonstrated that the GNAI2 message was on average decreased 54% and maximally decreased by 2.8 fold in clear cell carcinoma. GNAI2 message decreased in early stage cancer while message was increased compared to normal in advanced cancers. The changes in GNAI2 also correlated to deregulation of CREB, Fos, Myc, cyclins, Arf, the transition from estrogen dependence to independence, and metastatic potential. CONCLUSION: These data strongly implicate GNAI2 as a critical regulator of oncogenesis and an upstream driver of cancer progression in OvCa.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma/genética , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/genética , Neoplasias Ovarianas/genética , RNA Mensageiro/genética , Carcinoma/enzimologia , Carcinoma/patologia , Mineração de Dados , Bases de Dados Genéticas , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Estadiamento de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Ovarianas/enzimologia , Neoplasias Ovarianas/patologia , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Transcriptoma
15.
Cancer Manag Res ; 4: 195-205, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22904641

RESUMO

BACKGROUND: The vasoactive peptide bradykinin (BK) acts as a potent growth factor for normal kidney cells, but there have been few studies on the role of BK in renal cell carcinomas. PURPOSE: In this study, we tested the hypothesis that BK also acts as a mitogen in kidney carcinomas, and explored the effects of BK in human renal carcinoma A498 cells. METHODS: The presence of mRNAs for BK B(1) and BK B(2) receptors in A498 cells was demonstrated by reverse transcription-polymerase chain reaction. To study BK signaling pathways, we employed fluorescent measurements of intracellular Ca(2+), measured changes in extracellular pH as a reflection of Na(+)/H(+) exchange (NHE) with a Cytosensor microphysiometer, and assessed extracellular signal-regulated kinase (ERK) activation by Western blotting. RESULTS: Exposure to 100 nM of BK resulted in the rapid elevation of intracellular Ca(2+), caused a ≥30% increase in NHE activity, and a ≥300% increase in ERK phosphorylation. All BK signals were blocked by HOE140, a BK B(2) receptor antagonist, but not by a B(1) receptor antagonist. Inhibitor studies suggest that BK-induced ERK activation requires phospholipase C and protein kinase C activities, and is Ca(2+)/calmodulin-dependent. The amiloride analog 5-(N-methyl-N-isobutyl)-amiloride (MIA) blocked short-term NHE activation and inhibited ERK phosphorylation, suggesting that NHE is critical for ERK activation by BK. BK induced an approximately 40% increase in the proliferation of A498 cells as assessed by bromodeoxyuridine uptake. This effect was blocked by the ERK inhibitor PD98059, and was dependent on NHE activity. CONCLUSION: We conclude that BK exerts mitogenic effects in A498 cells via the BK B(2) receptor activation of growth-associated NHE and ERK.

16.
Am J Physiol Renal Physiol ; 302(12): F1583-94, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22461301

RESUMO

The intraglomerular renin-angiotensin system (RAS) is linked to the pathogenesis of progressive glomerular diseases. Glomerular podocytes and mesangial cells play distinct roles in the metabolism of angiotensin (ANG) peptides. However, our understanding of the RAS enzymatic capacity of glomerular endothelial cells (GEnCs) remains incomplete. We explored the mechanisms of endogenous cleavage of ANG substrates in cultured human GEnCs (hGEnCs) using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and isotope-labeled peptide quantification. Overall, hGEnCs metabolized ANG II at a significantly slower rate compared with podocytes, whereas the ANG I processing rate was comparable between glomerular cell types. ANG II was the most abundant fragment of ANG I, with lesser amount of ANG-(1-7) detected. Formation of ANG II from ANG I was largely abolished by an ANG-converting enzyme (ACE) inhibitor, whereas ANG-(1-7) formation was decreased by a prolylendopeptidase (PEP) inhibitor, but not by a neprilysin inhibitor. Cleavage of ANG II resulted in partial conversion to ANG-(1-7), a process that was attenuated by an ACE2 inhibitor, as well as by an inhibitor of PEP and prolylcarboxypeptidase. Further fragmentation of ANG-(1-7) to ANG-(1-5) was mediated by ACE. In addition, evidence of aminopeptidase N activity (APN) was demonstrated by detecting amelioration of conversion of ANG III to ANG IV by an APN inhibitor. While we failed to find expression or activity of aminopeptidase A, a modest activity attributable to aspartyl aminopeptidase was detected. Messenger RNA and gene expression of the implicated enzymes were confirmed. These results indicate that hGEnCs possess prominent ACE activity, but modest ANG II-metabolizing activity compared with that of podocytes. PEP, ACE2, prolylcarboxypeptidase, APN, and aspartyl aminopeptidase are also enzymes contained in hGEnCs that participate in membrane-bound ANG peptide cleavage. Injury to specific cell types within the glomeruli may alter the intrarenal RAS balance.


Assuntos
Angiotensina II/metabolismo , Angiotensina I/metabolismo , Células Endoteliais/metabolismo , Glomérulos Renais/metabolismo , Peptidil Dipeptidase A/metabolismo , Podócitos/metabolismo , Sistema Renina-Angiotensina/fisiologia , Carboxipeptidases/metabolismo , Células Cultivadas , Células Endoteliais/citologia , Humanos , Glomérulos Renais/citologia , Neprilisina/metabolismo , Podócitos/citologia
17.
J Biol Chem ; 286(28): 24656-65, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21464131

RESUMO

The 5-hydroxytryptamine 2A receptor (5-HT(2A)R) undergoes constitutive and agonist-dependent internalization. Despite many advances in our understanding of G protein-coupled receptor trafficking, the exact mechanism of endocytic sorting of G protein-coupled receptors remains obscure. Recently, we have reported a novel finding documenting a global role for the ubiquitin ligase c-Cbl in regulating vesicular sorting of epidermal growth factor receptor (Baldys, A., Göoz, M., Morinelli, T. A., Lee, M. H., Raymond, J. R., Jr., Luttrell, L. M., and Raymond, J. R., Sr. (2009) Biochemistry 48, 1462-1473). Thus, we tested the hypothesis that c-Cbl might play a role in 5-HT(2A)R recycling. In this study, we demonstrated an association of 5-HT(2A)R with c-Cbl. Furthermore, down-regulation of c-Cbl by RNA interference blocked efficient recycling of 5-HT(2A)R to the plasma membrane. Immunofluorescence microscopy revealed that 5-HT(2A) receptors were trapped in early endosome antigen 1- and Rab11-positive sorting endosomes in cells overexpressing c-Cbl mutants lacking carboxyl termini. This inhibitory effect was associated with a relative decrease in association of c-Cbl truncation proteins with the 5-HT(2A)R, compared with that observed for the full-length c-Cbl fusion protein. Consistent with the delayed recycling, 5-HT(2A)R resensitization was greatly attenuated in the presence of c-Cbl mutants lacking carboxyl termini, as detected by changes in the cytosolic calcium. Taken together, these studies have led to the discovery that the C-terminal region of c-Cbl plays a crucial role in the temporal and spatial control of 5-HT(2A)R recycling.


Assuntos
Endossomos/metabolismo , Proteínas Proto-Oncogênicas c-cbl/metabolismo , Receptor 5-HT2A de Serotonina/metabolismo , Sequência de Aminoácidos , Cálcio/metabolismo , Citosol/metabolismo , Endossomos/genética , Células HEK293 , Humanos , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-cbl/genética , Receptor 5-HT2A de Serotonina/genética , Deleção de Sequência , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
19.
Am J Physiol Cell Physiol ; 300(3): C647-56, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21148411

RESUMO

Angiotensin II (AII) binds to G protein-coupled receptor AT(1) and stimulates extracellular signal-regulated kinase (ERK), leading to vascular smooth muscle cells (VSMC) proliferation. Proliferation of mammalian cells is tightly regulated by adhesion to the extracellular matrix, which occurs via integrins. To study cross-talk between G protein-coupled receptor- and integrin-induced signaling, we hypothesized that integrins are involved in AII-induced proliferation of VSMC. Using Oligo GEArray and quantitative RT-PCR, we established that messages for α(1)-, α(5)-, α(V)-, and ß(1)-integrins are predominant in VSMC. VSMC were cultured on plastic dishes or on plates coated with either extracellular matrix or poly-d-lysine (which promotes electrostatic cell attachment independent of integrins). AII significantly induced proliferation in VSMC grown on collagen I or fibronectin, and this effect was blocked by the ERK inhibitor PD-98059, suggesting that AII-induced proliferation requires ERK activity. VSMC grown on collagen I or on fibronectin demonstrated approximately three- and approximately sixfold increases in ERK phosphorylation after stimulation with 100 nM AII, respectively, whereas VSMC grown on poly-d-lysine demonstrated no significant ERK activation, supporting the importance of integrin-mediated adhesion. AII-induced ERK activation was reduced by >65% by synthetic peptides containing an RGD (arginine-glycine-aspartic acid) sequence that inhibit α(5)ß(1)-integrin, and by ∼60% by the KTS (lysine-threonine-serine)-containing peptides specific for integrin-α(1)ß(1). Furthermore, neutralizing antibody against ß(1)-integrin and silencing of α(1), α(5), and ß(1) expression by transfecting VSMC with short interfering RNAs resulted in decreased AII-induced ERK activation. This work demonstrates roles for specific integrins (most likely α(5)ß(1) and α(1)ß(1)) in AII-induced proliferation of VSMC.


Assuntos
Angiotensina II/fisiologia , Proliferação de Células , Integrinas/fisiologia , Músculo Liso Vascular/fisiologia , Miócitos de Músculo Liso/fisiologia , Animais , Células Cultivadas , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Integrina alfa1beta1/genética , Integrina alfa1beta1/fisiologia , Integrina alfa5beta1/genética , Integrina alfa5beta1/fisiologia , Masculino , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptor Tipo 1 de Angiotensina/fisiologia
20.
J Biol Chem ; 285(44): 33816-25, 2010 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-20739277

RESUMO

ß(2)-adrenergic receptors (ß(2)-AR) are low abundance, integral membrane proteins that mediate the effects of catecholamines at the cell surface. Whereas the processes governing desensitization of activated ß(2)-ARs and their subsequent removal from the cell surface have been characterized in considerable detail, little is known about the mechanisms controlling trafficking of neo-synthesized receptors to the cell surface. Since the discovery of the signal peptide, the targeting of the integral membrane proteins to plasma membrane has been thought to be determined by structural features of the amino acid sequence alone. Here we report that localization of translationally silenced ß(2)-AR mRNA to the peripheral cytoplasmic regions is critical for receptor localization to the plasma membrane. ß(2)-AR mRNA is recognized by the nucleocytoplasmic shuttling RNA-binding protein HuR, which silences translational initiation while chaperoning the mRNA-protein complex to the cell periphery. When HuR expression is down-regulated, ß(2)-AR mRNA translation is initiated prematurely in perinuclear polyribosomes, leading to overproduction of receptors but defective trafficking to the plasma membrane. Our results underscore the importance of the spatiotemporal relationship between ß(2)-AR mRNA localization, translation, and trafficking to the plasma membrane, and establish a novel mechanism whereby G protein-coupled receptor (GPCR) responsiveness is regulated by RNA-based signals.


Assuntos
Membrana Celular/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Antígenos de Superfície/metabolismo , Transporte Biológico , Células CHO , Linhagem Celular Tumoral , Cricetinae , Cricetulus , Proteínas ELAV , Proteína Semelhante a ELAV 1 , Humanos , Modelos Biológicos , Polirribossomos/metabolismo , Ligação Proteica , Sinais Direcionadores de Proteínas , Proteínas de Ligação a RNA/metabolismo , Receptores Adrenérgicos beta 2/metabolismo
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