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1.
WMJ ; 123(2): 106-112, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38718238

RESUMEN

INTRODUCTION: Implicit racial bias, defined as unreasoned judgement based solely on an individual's skin color, is a persistent barrier to quality medical care for people of color in the United States. Early, learner-centered intervention is crucial to establish cultural competence within health professional training programs. METHODS: Over 3 academic years, preclinical, second-year medical students were asked to submit an anonymous critical reflection regarding skin tone in medicine (n=794). Critical reflection is an instructional approach that encourages students to investigate their own thoughts and actions. Course credit was given based on the honor system. Reflection submission content and student feedback were analyzed quantitatively and qualitatively using constructivist thematic analysis. RESULTS: Most students completed the assignment (93.0%) and reported feeling comfortable expressing themselves honestly in the anonymous format (84.6%). Students' comfort level with honesty declined if they would have had to identify themselves (50.8%). Student comments indicated relief to have a place to process experiences and emphasized the importance of anonymity for value of this assignment. Thematic analysis identified 2 themes and 13 subthemes among student submissions. Submissions varied in format and typically contained multiple codes (4.08 ± 1.77 subthemes), indicating that students participated meaningfully in the assignment. CONCLUSIONS: Although some educators may hesitate to address these topics, students at our institution appreciated having a space to process their thoughts. This assignment structure is an effective way for educators to address a difficult, sensitive, and important topic in a meaningful way with students.


Asunto(s)
Actitud del Personal de Salud , Educación de Pregrado en Medicina , Racismo , Estudiantes de Medicina , Adulto , Femenino , Humanos , Masculino , Competencia Cultural , Estudiantes de Medicina/psicología , Estados Unidos , Wisconsin
2.
J Med Educ Curric Dev ; 10: 23821205231200731, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37692559

RESUMEN

Leadership training is a necessary component of undergraduate medical education. Our group successfully implemented a student-led organization starting from 2016 (Student Leadership Development Initiative; SLDI) that aimed to provide medical students with exposure to physician-leader career paths in an informal, organic, interactive setting. The COVID-19 pandemic necessitated a shift to online programming, and given the high prevalence of ZOOMTM fatigue, we incorporated monthly, freely available, self-directed modules as an additional leadership training opportunity. The goals of this study are to assess the (1) feasibility of and participation in a virtual student organization focused on leadership training, (2) whether students' perceptions of the importance of leadership were associated with participation in SLDI, and (3) lessons learned from transitioning to virtual modalities. An anonymous, retrospective cross-sectional survey with 13-items was distributed through an email listserv and a 6-question survey was sent to attendees following each virtual group-discussion. A Fisher's exact test was conducted to assess whether the number of modules completed was associated with students' perception of leadership importance. Survey results showed that 85% strongly agreed or agreed that SLDI helped them develop professional goals and career paths, and 74% reported benefits in becoming more compassionate physician leaders and valuing wellness. All respondents completed ≥1 self-directed module, and the students' perception of leadership importance did not influence the number of self-directed modules completed (p > .05). Most participants (63%) attended ≥67% of virtual events, and postevent feedback was positive; however, only 46% of respondents reported meeting someone new at events and 32% reported that they intended on connecting with new contacts. Our results suggest that virtual leadership student-organization, involving small-group discussions and self-directed modules, is feasible and beneficial for medical students. However, the inability to promote meaningful networking opportunities is a major limitation of a virtual training model.

3.
Otol Neurotol ; 43(9): 1078-1084, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-35960883

RESUMEN

OBJECTIVE: To identify demographic and clinical features impacting initial treatment pathway for vestibular schwannoma. STUDY DESIGN: Retrospective chart review. SETTING: Tertiary care academic medical center. PATIENTS: Patients diagnosed with vestibular schwannoma between 2009 and 2019. INTERVENTIONS: Observation, stereotactic radiosurgery, or microsurgical resection. MAIN OUTCOME MEASURES: χ 2 Test, one-way analysis of variance, and multivariate logistic regression were used to correlate demographic and clinical factors with initial treatment pathway for 197 newly diagnosed vestibular schwannoma patients. RESULTS: Among 197 patients, 93 (47%) were initially treated with observation, 60 (30%) with stereotactic radiation (Gamma Knife) and 44 (22%) with surgical resection. Age univariately had no statistically significant impact on initial pathway, but those undergoing surgery trended toward a younger demographic (49.1 yr [surgery] versus 57.2 yr [observation] versus 59.0 yr [Gamma Knife]). Men were more likely to be initially observed than women ( p = 0.04). Patients initially observed were more likely to have a lower Koos classification ( p < 0.001) and have better tumor-ear hearing ( p = 0.03). Only 34.4% of patients living outside the local geographic region were initially observed compared with 53.0% living locally ( p = 0.055). Surgeon correlated with initial treatment ( p = 0.04) but did not maintain significance when adjusting for hearing level or tumor size. A multiple linear regression model found age, maximum tumor diameter, and Koos class to correlate with initial treatment pathway ( p < 0.0001, r2 = 0.42). CONCLUSION: Initial treatment pathway for newly diagnosed vestibular schwannoma is impacted by demographic factors such as age, sex, and geographic proximity to the medical center. Clinical features including hearing level and tumor size also correlated with initial treatment modality.


Asunto(s)
Neuroma Acústico , Radiocirugia , Demografía , Femenino , Humanos , Masculino , Neuroma Acústico/patología , Radiocirugia/efectos adversos , Estudios Retrospectivos , Resultado del Tratamiento
4.
Int J Circumpolar Health ; 80(1): 1867439, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33463403

RESUMEN

The aim of our study was to explore the association between self-reported health factors and self-rated health (SRH) among an older rural population in northern Sweden and whether confounders optimistic outlook or daily moderate-intensity physical activity could moderate the association between self-reported health factors and SRH, controlling for age. The study is based on a sample (N = 1946) from the "Health on Equal Terms" Västernorrland survey 2018 aged 65-84. Prevalence and multivariate logistic regression analyses were performed. The results indicated most rural older people perceived very good or good SRH, though physical and mental health issues and impaired mobility increased with advanced age. Mental well-being exhibited a stronger association with poor SRH than physical health or impaired mobility. In addition, confounders optimistic outlook and daily moderate-intensity physical activity, separately and together could moderate the association between health factors and poor SRH. In conclusion, older people in a rural setting perceived good health, despite common physical and mental health issues. Promoting daily moderate-intensity physical activity and activities contributing to an optimistic outlook can protect against poor SRH in old age.


Asunto(s)
Envejecimiento Saludable , Población Rural , Anciano , Estudios Transversales , Ejercicio Físico , Estado de Salud , Humanos , Suecia/epidemiología
5.
Health Psychol Res ; 9(1): 25208, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35106398

RESUMEN

INTRODUCTION: Fibromyalgia (FM) is a complex disorder characterized primarily by chronic, widespread musculoskeletal pain. Currently, the Food and Drug Administration (FDA) has approved the use of three medications to treat FM: pregabalin, duloxetine, and milnacipran. The pharmaceutical intervention has lacked consistent pain relief among all patients. Therefore, the investigation into alternative treatment options has grown in interest. This narrative review aims to evaluate the evidence regarding vitamin D for the treatment of FM. METHODS: Narrative review. RESULTS: Low serum vitamin D has been linked to various chronic pain states. An association between vitamin D deficiency and FM has been reported but is controversial in the literature. Some studies have documented the beneficial effects of vitamin D supplementation on reducing pain symptoms and improving the overall quality of life in those with FM. Despite these positive findings, many of the studies regarding this topic lack adequate power to make substantial conclusions about the effects of vitamin D on FM. CONCLUSION: Existing studies provide promising results. However, additional high-quality data on vitamin D supplementation is needed before recommendations for pain management can be made. Vitamin D supplementation is inexpensive, has minimal side effects, and can benefit FM patients regardless of its efficacy in pain control. Additionally, high-quality studies are warranted to fully elucidate the potential of vitamin D to manage chronic pain in FM.

6.
FEBS J ; 275(14): 3706-17, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18549450

RESUMEN

Cytochrome P450 (P450) 4X1 is one of the so-called 'orphan' P450s without an assigned biological function. Codon-optimized P450 4X1 and a number of N-terminal modified sequences were expressed in Escherichia coli. Native P450 4X1 showed a characteristic P450 spectrum but low expression in E. coli DH5alpha cells (< 100 nmol P450.L(-1)). The highest level of expression (300-450 nmol P450.L(-1) culture) was achieved with a bicistronic P450 4X1 construct (N-terminal MAKKTSSKGKL, change of E2A, amino acids 3-44 truncated). Anandamide (arachidonoyl ethanolamide) has emerged as an important signaling molecule in the neurovascular cascade. Recombinant P450 4X1 protein, co-expressed with human NADPH-P450 reductase in E. coli, was found to convert the natural endocannabinoid anandamide to a single monooxygenated product, 14,15-epoxyeicosatrienoic (EET) ethanolamide. A stable anandamide analog (CD-25) was also converted to a monooxygenated product. Arachidonic acid was oxidized more slowly to 14,15- and 8,9-EETs but only in the presence of cytochrome b(5). Other fatty acids were investigated as putative substrates but showed only little or minor oxidation. Real-time PCR analysis demonstrated extrahepatic mRNA expression, including several human brain structures (cerebellum, amygdala and basal ganglia), in addition to expression in human heart, liver, prostate and breast. The highest mRNA expression levels were detected in amygdala and skin. The ability of P450 4X1 to generate anandamide derivatives and the mRNA distribution pattern suggest a potential role for P450 4X1 in anandamide signaling in the brain.


Asunto(s)
Ácidos Araquidónicos/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Alcamidas Poliinsaturadas/metabolismo , Adulto , Secuencia de Aminoácidos , Secuencia de Bases , Catálisis , Codón , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/aislamiento & purificación , ADN Complementario/biosíntesis , Endocannabinoides , Humanos , Datos de Secuencia Molecular , Oxidación-Reducción , Reacción en Cadena de la Polimerasa , Eliminación de Secuencia , Distribución Tisular
7.
Drug Metab Dispos ; 36(9): 1930-7, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18541694

RESUMEN

Cytochrome P450 (P450) 20A1 is one of the so-called "orphan" P450s without assigned biological function. mRNA expression was detected in human liver, and extrahepatic expression was noted in several human brain regions, including substantia nigra, hippocampus, and amygdala, using conventional polymerase chain reaction and RNA dot blot analysis. Adult human liver contained 3-fold higher overall mRNA levels than whole brain, although specific regions (i.e., hippocampus and substantia nigra) exhibited higher mRNA expression levels than liver. Orthologous full-length and truncated transcripts of P450 20A1 were transcribed and sequenced from rat liver, heart, and brain. In rat, the concentrations of full-length transcripts were 3- to 4-fold higher in brain and heart than in liver. In situ hybridization of rat whole brain sections showed an mRNA expression pattern similar to that observed for human P450 20A1, indicating expression in substantia nigra, hippocampus, and amygdala. A number of N-terminal modifications of the codon-optimized human P450 20A1 sequence were prepared and expressed in Escherichia coli, and two of the truncated derivatives showed characteristic P450 spectra (200-280 nmol of P450/l). Although the recombinant enzyme system oxidized NADPH, no catalytic activity was observed with the heterologously expressed protein when a number of potential steroids and biogenic amines were surveyed as potential substrates. The function of P450 20A1 remains unknown; however, the sites of mRNA expression in human brain and the conservation among species may suggest possible neurophysiological function.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , ARN Mensajero/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Catálisis , Colesterol/metabolismo , ADN Complementario , Humanos , Hibridación Fluorescente in Situ , Espectrometría de Masas , Datos de Secuencia Molecular , Oxidación-Reducción , Polimorfismo de Nucleótido Simple , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
8.
Drug Metab Rev ; 39(2-3): 627-37, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17786643

RESUMEN

Of the 57 human cytochromes P450 (P450) and 58 pseudogenes discovered to date, (http://drnelson.utmem.edu/CytochromeP450.html ), 1/4 still remain "orphans" in the sense that their function, expression sites, and regulation are still largely not elucidated. The post-human genome-sequencing project era has presented the research community with novel challenges. Despite many insights gathered about gene location and genetic variations in our human genome, we still lack important knowledge about these novel P450 enzymes and their functions in endogenous and exogenous metabolism, as well as their possible roles in the metabolism of toxicants and carcinogens. Our own list of such orphans currently consists of 13 members: P450 2A7, 2S1, 2U1, 2W1, 3A43, 4A22, 4F11, 4F22, 4V2, 4X1, 4Z1, 20A1, and 27C1. Some of the orphans, e.g. P450s 2W1 and 2U1, already have putative assigned functions in arachidonic acid metabolism and may activate carcinogens. However, at this point, for the majority of them more knowledge is available about their genes and single nucleotide polymorphisms than of their biological functions. It is noteworthy that most P450 orphans express high interspecies sequence conservation and have orthologs in rodents (e.g. CYP4X1/Cyp4x1, CYP4V2/Cyp4v3). This review summarizes recent knowledge about the P450 orphans and questions remaining about their specific roles in human metabolism.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Animales , Sistema Enzimático del Citocromo P-450/clasificación , Humanos , Preparaciones Farmacéuticas/metabolismo , Seudogenes/genética , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Toxicología
9.
Vet Ital ; 43(3): 513-8, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-20422529

RESUMEN

Due to the spread of bluetongue (BT) in Europe in the last decade, a sentinel surveillance programme was initiated for Switzerland in 2003, consisting of serological sampling of sentinel cattle tested for BT virus antibodies, as well as entomological trapping of Culicoides midges from June until October. The aim of this study was to create a 'suitability map' of Switzerland, indicating areas of potential disease occurrence based on the biological parameters of Obsoletus Complex habitat. Data on Culicoides catches from insect traps together with various environmental parameters were recorded and analysed. A multiple regression analysis was performed to determine correlation between the environmental conditions and vector abundance. Meteorological data were collected from 50 geo-referenced weather stations across Switzerland and maps of temperature, precipitation and altitude were created. A range of values of temperature, precipitation and altitude influencing vector biology were obtained from the literature. The final combined map highlighted areas in Switzerland which are most suitable for vector presence, hence implying a higher probability of disease occurrence given the presence of susceptible animals. The results confirmed the need for an early warning system for the surveillance of BT disease and its vectors in Switzerland.

10.
Prostaglandins Other Lipid Mediat ; 79(1-2): 114-25, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16516815

RESUMEN

Cyclooxygenase-2 (COX-2), cytochrome P450 4F8 (CYP4F8), and microsomal PGE synthase-1 (mPGES-1) form PGE and 19-hydroxy-PGE in human seminal vesicles. We have examined COX-2, CYP4F8, and mPGES-1 in normal skin and in psoriasis. All three enzymes were detected in epidermis by immunofluorescence and co-localized in the suprabasal cell layers. In lesional psoriasis the enzymes were also co-localized in the basal cell layers. Real-time RT-PCR analysis suggested that CYP4F8 mRNA was induced 15-fold in lesional compared to non-lesional epidermis. mRNA of all enzymes were present in cultured HEK and HaCaT cells, but the prominent induction of CYP4F8 mRNA in psoriasis could not be mimicked by treatment of these keratinocytes with a mixture of inflammatory cytokines or with phorbol 12-myristate-13-acetate. The function of CYP4F8 in epidermis might be related to lipid oxidation and keratinocyte proliferation.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas/biosíntesis , Ciclooxigenasa 2/biosíntesis , Epidermis/enzimología , Regulación Enzimológica de la Expresión Génica , Oxidorreductasas Intramoleculares/biosíntesis , Proteínas de la Membrana/biosíntesis , Psoriasis/enzimología , Carcinógenos/farmacología , Línea Celular , Citocinas/farmacología , Epidermis/fisiología , Humanos , Inflamación/enzimología , Inflamación/patología , Queratinocitos/enzimología , Queratinocitos/patología , Prostaglandina-E Sintasas , Psoriasis/patología , ARN Mensajero/biosíntesis , Acetato de Tetradecanoilforbol/farmacología
11.
Biochem Biophys Res Commun ; 341(2): 451-8, 2006 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-16426568

RESUMEN

A novel human cytochrome P450, CYP2W1, was cloned and expressed heterologously. No or very low CYP2W1 mRNA levels were detected in fetal and adult human tissues, expression was however seen in 54% of human tumor samples investigated (n=37), in particular colon and adrenal tumors. Western blotting also revealed high expression of CYP2W1 in some human colon tumors. In rat tissues, CYP2W1 mRNA was expressed preferentially in fetal but also in adult colon. The CYP2W1 gene was shown to encompass one functional CpG island in the exon 1-intron 1 region which was methylated in cell lines lacking CYP2W1 expression, but unmethylated in cells expressing CYP2W1. Re-expression of CYP2W1 was seen following demethylation by 5-Aza-2'-deoxycytidine. Transfection of HEK293 cells with CYP2W1 caused the formation of a properly folded enzyme, which was catalytically active with arachidonic acid as a substrate. It is concluded that CYP2W1 represents a tumor-specific P450 isoform with potential importance as a drug target in cancer therapy.


Asunto(s)
Colon/metabolismo , Sistema Enzimático del Citocromo P-450/biosíntesis , Regulación Neoplásica de la Expresión Génica , Regulación de la Expresión Génica , Oxigenasas de Función Mixta/biosíntesis , Neoplasias de las Glándulas Suprarrenales/metabolismo , Animales , Ácido Araquidónico/metabolismo , Azacitidina/análogos & derivados , Azacitidina/metabolismo , Western Blotting , Catálisis , Línea Celular , Línea Celular Tumoral , Clonación Molecular , Colon/embriología , Neoplasias del Colon/metabolismo , Islas de CpG , Sistema Enzimático del Citocromo P-450/genética , Familia 2 del Citocromo P450 , Metilación de ADN , Decitabina , Exones , Humanos , Intrones , Pliegue de Proteína , Isoformas de Proteínas , ARN Mensajero/metabolismo , Ratas , Transfección
12.
Arch Biochem Biophys ; 441(2): 174-81, 2005 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-16112640

RESUMEN

Recombinant CYP4F8 and CYP4F12 metabolize prostaglandin H2 (PGH2) analogs by omega2- and omega3-hydroxylation and arachidonic acid (20:4n-6) by omega3-hydroxylation. CYP4F8 was found to catalyze epoxidation of docosahexaenoic acid (22:6n-3) and docosapentaenoic acid (22:5n-3) and omega3-hydroxylation of 22:5n-6. CYP4F12 oxidized 22:6n-3 and 22:5n-3 in the same way, but 22:5n-6 was a poor substrate. The products were identified by liquid chromatography-mass spectrometry. The missense mutation 374A>T of CYP4F8 (Tyr125Phe in substrate recognition site-1 (SRS-1)) occurs in low frequency. This variant oxidized two PGH2 analogs, U-51605 and U-44069, in analogy with CYP4F8, but 20:4n-6 and 22:5n-6 were not oxidized. CYP4F enzymes with omega-hydroxylase activity contain a heme-binding Glu residue, whereas CYP4F8 (and CYP4F12) with omega2- and omega 3-hydroxylase activities has a Gly residue in this position of SRS-4. The mutant CYP4F8 Gly328Glu oxidized U-51605 and U-44069 as recombinant CYP4F8, but the hydroxylation of arachidonic acid was shifted from C-18 to C-19. Single amino acid substitutions in SRS-1 and SRS-4 of CYP4F8 may thus influence oxygenation of certain substrates. We conclude that CYP4F8 and CYP4F12 catalyze epoxidation of 22:6n-3 and 22:5n-3, and CYP4F8 omega3-hydroxylation of 22:5n-6.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas/química , Ácidos Grasos Insaturados/química , Glicina/química , Oxigenasas de Función Mixta/química , Oxígeno/química , Proteínas Recombinantes/química , Tirosina/química , Sustitución de Aminoácidos , Hidrocarburo de Aril Hidroxilasas/genética , Sitios de Unión , Catálisis , Activación Enzimática , Ácidos Grasos Insaturados/genética , Glicina/genética , Oxigenasas de Función Mixta/genética , Peso Molecular , Mutagénesis Sitio-Dirigida , Oxidación-Reducción , Unión Proteica , Ingeniería de Proteínas/métodos , Relación Estructura-Actividad , Tirosina/genética
13.
Prostaglandins Other Lipid Mediat ; 75(1-4): 47-64, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15789615

RESUMEN

The predominating prostaglandins of human seminal fluid are 19R-hydroxyprostaglandins E1 and E2, conceivably formed sequentially by prostaglandin H (PGH) synthase-2, PGH 19-hydroxylase (CYP4F8), and microsomal PGE synthase-1 of seminal vesicles. Our aim was to study this enzyme system. Quantification by real-time PCR suggested that the transcripts of PGH synthase-2, CYP4F8, and microsomal PGE synthase-1 were abundant and correlated in seminal vesicles of seven patients (p < 0.05). The three enzymes were detected in seminal vesicles by Western blot analysis, and immunohistological analysis confirmed the localization to the epithelia of seminal vesicles and distal vas deferens. Immunofluorescence analysis showed co-localization of the three enzymes in epithelial cells of seminal vesicles and vas deferens. 19-Hydroxy-PGE compounds were detected by mass spectrometry in the mucosa of distal vas deferens. Recombinant CYP4F8 catalyzes n-2 hydroxylation of PGH1 and PGH2 and n-3 hydroxylation of arachidonic acid. Arachidonic acid was oxidized to 18-hydroxyarachidonic acid and to PGE2 and by microsomes of seminal vesicles in the presence of NADPH and GSH, and to relatively small amounts of 19-hydroxy-PGE2. We conclude that PGH synthase-2, CYP4F8, and PGE synthase-1 likely forms 19-hydroxy-PGE compounds in seminal vesicles and vas deferens, but the catalytic properties of CYP4F8 suggest additional biological functions. Recombinant CYP4F8 was also found to catalyze n-2 hydroxylation of PGI2 and carbaprostacyclin (Km to approximately 40 microM), and n-2 and n-3 hydroxylation of carbocyclic TXA2.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas/metabolismo , Oxidorreductasas Intramoleculares/metabolismo , Prostaglandina-Endoperóxido Sintasas/metabolismo , Prostaglandinas/biosíntesis , Semen/fisiología , Vesículas Seminales/enzimología , Conducto Deferente/enzimología , Hidrocarburo de Aril Hidroxilasas/genética , Secuencia de Bases , Ciclooxigenasa 2 , Cartilla de ADN , Humanos , Oxidorreductasas Intramoleculares/genética , Masculino , Proteínas de la Membrana , Prostaglandina-E Sintasas , Prostaglandina-Endoperóxido Sintasas/genética , Proteínas Recombinantes/metabolismo
14.
Biochem Biophys Res Commun ; 327(4): 1052-7, 2005 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-15652503

RESUMEN

Arachidonic acid is oxidized by cytochromes P450 2C (CYP2C) to epoxyeicosatrienoic acids (EETs), possessing vasoactive properties, with 11,12-EET as the endothelium derived hyperpolarization factor. Genetic variants of CYP2C enzymes have altered drug metabolizing capacity. Our primary aim was to determine whether EET biosynthesis differed in human liver microsomes with known CYP2C genotypes. Human liver microsomes (n = 25) of different CYP2C genotypes or yeast-expressed CYP2C enzymes were used. Analysis of metabolites was performed by liquid chromatography/mass spectrometry. Samples genotyped as CYP2C8*3/*3/CYP2C9*2/*2 exhibited a 34% (p < 0.05) decreased EET biosynthesis, compared to other CYP2C8/CYP2C9 haplotypes. Inhibition experiments suggested CYP2C8 and CYP2C9 to be the predominant catalysts of EETs. We found no differences between the three recombinantly expressed CYP2C9 variants, but CYP2C8.1 had lower K(m) than these isoforms. In conclusion, there are genetic differences in the CYP2C-dependent oxidation of arachidonic acid to vasoactive metabolites, of which the relevance to cardiovascular pathophysiology is still unclear.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Ácidos Eicosanoicos/metabolismo , Polimorfismo Genético/genética , Cromatografía Líquida de Alta Presión , Ácidos Eicosanoicos/química , Humanos , Cinética , Espectrometría de Masas , Microsomas Hepáticos/enzimología , Microsomas Hepáticos/metabolismo
15.
Basic Clin Pharmacol Toxicol ; 94(4): 177-83, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15078342

RESUMEN

Cytochrome P450 4F12 (CYP4F12) was originally cloned from human liver and small intestine. CYP4F12 can oxidize arachidonic acid, two stable prostaglandin H2 analogues, and an antihistamine, ebastine, but the tissue distribution and catalytic properties of CYP4F12 have not been fully investigated. An antipeptide polyclonal antibody was raised against the C-terminal of CYP4F12 (PLNVGLQ), evaluated by Western blot analysis and used for immunohistological analysis of 50 human tissues. Western blot analysis of recombinant CYP4F12, expressed in yeast, and microsomal proteins from adult and foetal liver, kidney, placenta at term, seminal vesicles, the prostate gland and purified prostasomes showed that the polyclonal antibody detected a protein of the expected size, approximately 60 kDa. CYP4F12 mRNA could be detected in seminal vesicles and prostate gland by reverse transcription-PCR. Prominent CYP4F12 immunoreactivity occurred, inter alia, in the epithelial cells of the gastrointestinal tract (stomach, small intestine, and colon), collecting tubules, transitional epithelium, ovarian follicles, the endothelium of microvessels of placental villi (first trimester), and epidermis. We screened recombinant CYP4F12 for catalytic activity. Arachidonic acid (20:4n-6) was hydroxylated at C18 and laurate at C11, but significant amounts of metabolites of 18:2n-6, 20:3n-9, 20:5n-3, 22:5n-6, and some prostaglandins could not be detected. We conclude that CYP4F12 is widely distributed in gastrointestinal and urogenital epithelia and exhibits a narrow substrate specificity.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas/biosíntesis , Mucosa Intestinal/metabolismo , Oxigenasas de Función Mixta/biosíntesis , Sistema Urogenital/metabolismo , Hidrocarburo de Aril Hidroxilasas/genética , Catálisis , Eicosanoides/metabolismo , Epidermis/metabolismo , Epitelio/metabolismo , Ácidos Grasos/metabolismo , Femenino , Humanos , Técnicas In Vitro , Intestino Delgado/metabolismo , Riñón/metabolismo , Hígado/metabolismo , Masculino , Oxigenasas de Función Mixta/genética , Especificidad de Órganos , Placenta/metabolismo , Embarazo , Próstata/metabolismo , ARN Mensajero/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Vesículas Seminales/metabolismo , Especificidad por Sustrato
16.
Arch Biochem Biophys ; 409(1): 188-96, 2003 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-12464258

RESUMEN

Our aim was to determine the tissue distribution of CYP4F8, which occurs in human seminal vesicles and catalyzes 19-hydroxylation of prostaglandin H(1) and H(2) in vitro (J. Bylund, M. Hidestrard, M. Ingelman-Sundberg, E.H. Oliw, J. Biol. Chem. 275 (2000) 21844-21849). Polyclonal antibodies were raised in rabbits against RVEPLG, the C-terminal end of CYP4F8, and purified by affinity chromatography. Screening of 50 human tissues for CYP4F8 immunoreactivity revealed protein expression, inter alia, in seminal vesicles, epidermis, hair follicles, sweat glands, corneal epithelium, proximal renal tubules, and epithelial linings of the gut and urinary tract. The CYP4F8 transcripts were detected by reverse transcription polymerase chain reaction and by Northern blot analysis. There was a prominent induction of CYP4F8 immunoreactivity and mRNA in psoriasis in comparison with unaffected epidermis of the same patients. The cDNA of CYP4F8 from plucked scalp hair roots was identical with the genital cDNA sequence. We conclude that CYP4F8 is present in epithelial linings and up regulated in epidermis of psoriatic lesions.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas/biosíntesis , Epidermis/enzimología , Epitelio/enzimología , Psoriasis/enzimología , Northern Blotting , Western Blotting , Catálisis , ADN/metabolismo , ADN Complementario/metabolismo , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Inmunohistoquímica , Masculino , ARN Mensajero/metabolismo , Proteínas Recombinantes/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo
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