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1.
JAMA Netw Open ; 7(9): e2431997, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39259543

RESUMEN

Importance: Uncontrolled hypertension is a major contributor to cardiovascular disease (CVD) in the US. Objective: To determine the prevalence of hypertension control cascade outcomes (hypertension awareness, treatment recommendations, and medication use) among individuals with uncontrolled hypertension to inform action across cascade levels. Design, Setting, and Participants: This weighted cross-sectional study used January 2017 to March 2020 National Health and Nutrition Examination Survey (NHANES) data from noninstitutionalized adults aged 18 years or older in the US with uncontrolled hypertension. Data analysis occurred from January to February 2024. Exposure: Calendar year of response to the NHANES survey. Main Outcomes and Measures: Mean blood pressure (BP) was computed using up to 3 measurements. Uncontrolled hypertension was defined as systolic BP of 130 mm Hg or greater or diastolic BP of 80 mm Hg or greater, regardless of medication use. Outcomes included patient awareness of hypertension, treatment recommendations, and medication use. To estimate population totals by subgroup, the age-standardized proportion of each outcome was multiplied by the estimated number of adults with uncontrolled hypertension. Results: The study included 3129 US adults with uncontrolled hypertension (1675 male [weighted percentage, 52.3%]; 775 aged 18 to 44 years [weighted percentage, 29.4%]; 1306 aged 45 to 64 years [weighted percentage, 41.4%]; 1048 aged 65 years or older [weighted percentage, 29.2%]), resulting in a population estimate of 100.4 million adults (weighted percentage, 83.7%) with uncontrolled hypertension. More than one-half of study participants (57.8 million adults [weighted percentage, 57.6%]) were unaware that they had hypertension, and of the 35.0 million who were aware and met criteria for antihypertensive medication, 24.8 million (weighted percentage, 70.8%) took the medication but had hypertension that remained uncontrolled. These negative outcomes in the hypertension control cascade occurred across demographic groups, with notably high prevalence among younger adults and individuals engaged in health care. Among an estimated 30.1 million adults aged 18 to 44 years with hypertension, 10.4 of 11.3 million females (weighted percentage, 91.8%) and 17.7 million of 18.8 million males (weighted percentage, 94.3%) had uncontrolled hypertension. Of the 10.4 million females, 7.2 million (weighted percentage, 68.8%) were unaware of their hypertension status, and of the 17.7 million males, 12.0 million (weighted percentage, 68.1%) were unaware. Additionally, 9.9 of 13.0 million adults with uncontrolled hypertension (weighted percentage, 75.7%) reported no health care visits in the past year and were unaware. Conversely, among 70.6 million adults with uncontrolled hypertension reporting 2 or more health care visits, approximately one-half (36.6 million [weighted percentage, 51.8%]) were unaware. Conclusions and Relevance: In this cross-sectional study, more than 50% of adults with uncontrolled hypertension in the US were unaware of their hypertension and were untreated, and 70.8% of those who were treated had hypertension that remained uncontrolled. These findings have serious implications for the nation's overall health given the association of hypertension with increased risk for CVD.


Asunto(s)
Antihipertensivos , Hipertensión , Encuestas Nutricionales , Humanos , Hipertensión/epidemiología , Hipertensión/tratamiento farmacológico , Masculino , Femenino , Persona de Mediana Edad , Estudios Transversales , Adulto , Estados Unidos/epidemiología , Antihipertensivos/uso terapéutico , Anciano , Adolescente , Adulto Joven , Prevalencia , Presión Sanguínea/fisiología , Conocimientos, Actitudes y Práctica en Salud
2.
J Womens Health (Larchmt) ; 33(5): 553-562, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38529887

RESUMEN

Hypertension in pregnancy (HP) includes eclampsia/preeclampsia, chronic hypertension, superimposed preeclampsia, and gestational hypertension. In the United States, HP prevalence doubled over the last three decades, based on birth certificate data. In 2019, the estimated percent of births with a history of HP varied from 10.1% to 15.9% for birth certificate data and hospital discharge records, respectively. The use of electronic medical records may result in identifying an additional third to half of undiagnosed cases of HP. Individuals with gestational hypertension or preeclampsia are at 3.5 times higher risk of progressing to chronic hypertension and from 1.7 to 2.8 times higher risk of developing cardiovascular disease (CVD) after childbirth compared with individuals without these conditions. Interventions to identify and address CVD risk factors among individuals with HP are most effective if started during the first 6 weeks postpartum and implemented during the first year after childbirth. Providing access to affordable health care during the first 12 months after delivery may ensure healthy longevity for individuals with HP. Average attendance rates for postpartum visits in the United States are 72.1%, but the rates vary significantly (from 24.9% to 96.5%). Moreover, even among individuals with CVD risk factors who attend postpartum visits, approximately 40% do not receive counseling on a healthy lifestyle. In the United States, as of the end of September 2023, 38 states and the District of Columbia have extended Medicaid coverage eligibility, eight states plan to implement it, and two states proposed a limited coverage extension from 2 to 12 months after childbirth. Currently, data gaps exist in national health surveillance and health systems to identify and monitor HP. Using multiple data sources, incorporating electronic medical record data algorithms, and standardizing data definitions can improve surveillance, provide opportunities to better track progress, and may help in developing targeted policy recommendations.


Asunto(s)
Hipertensión Inducida en el Embarazo , Humanos , Femenino , Embarazo , Estados Unidos/epidemiología , Hipertensión Inducida en el Embarazo/epidemiología , Factores de Riesgo , Prevalencia , Vigilancia de la Población , Preeclampsia/epidemiología , Adulto
6.
J Womens Health (Larchmt) ; 31(10): 1380-1386, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36154466

RESUMEN

More than 56 million women in the United States have hypertension, including almost one in five women of reproductive age. The prevalence of hypertensive disorders of pregnancy is on the rise, putting more women at risk for adverse pregnancy-related outcomes and atherosclerotic cardiovascular disease later in life. Hypertension can be better detected and controlled in women throughout their life course by supporting self-measured blood pressure monitoring. In this study, we present some potential strategies for strengthening our nation's ability to address hypertension in women focusing on pregnancy-related considerations for self-measured blood pressure monitoring.


Asunto(s)
Determinación de la Presión Sanguínea , Hipertensión , Embarazo , Femenino , Humanos , Presión Sanguínea , Hipertensión/diagnóstico , Hipertensión/epidemiología , Resultado del Embarazo , Monitoreo Fisiológico
7.
J Am Heart Assoc ; 11(7): e024785, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-35301870

RESUMEN

Background Amid stagnating declines in national cardiovascular disease (CVD) mortality, documenting trends in county-level hypertension-related CVD death rates can help activate local efforts prioritizing hypertension prevention, detection, and control. Methods and Results Using death certificate data from the National Vital Statistics System, Bayesian spatiotemporal models were used to estimate county-level hypertension-related CVD death rates and corresponding trends during 2000 to 2010 and 2010 to 2019 for adults aged ≥35 years overall and by age group, race or ethnicity, and sex. Among adults aged 35 to 64 years, county-level hypertension-related CVD death rates increased from a median of 23.2 per 100 000 in 2000 to 43.4 per 100 000 in 2019. Among adults aged ≥65 years, county-level hypertension-related CVD death rates increased from a median of 362.1 per 100 000 in 2000 to 430.1 per 100 000 in 2019. Increases were larger and more prevalent among adults aged 35 to 64 years than those aged ≥65 years. More than 75% of counties experienced increasing hypertension-related CVD death rates among patients aged 35 to 64 years during 2000 to 2010 and 2010 to 2019 (76.2% [95% credible interval, 74.7-78.4] and 86.2% [95% credible interval, 84.6-87.6], respectively), compared with 48.2% (95% credible interval, 47.0-49.7) during 2000 to 2010 and 66.1% (95% credible interval, 64.9-67.1) for patients aged ≥65 years. The highest rates for both age groups were among men and Black populations. All racial and ethnic categories in both age groups experienced widespread county-level increases. Conclusions Large, widespread county-level increases in hypertension-related CVD mortality sound an alarm for intensified clinical and public health actions to improve hypertension prevention, detection, and control and prevent subsequent CVD deaths in counties across the nation.


Asunto(s)
Enfermedades Cardiovasculares , Cardiopatías , Hipertensión , Adulto , Anciano , Teorema de Bayes , Enfermedades Cardiovasculares/epidemiología , Etnicidad , Humanos , Hipertensión/epidemiología , Masculino , Persona de Mediana Edad , Estados Unidos/epidemiología
8.
Am J Hypertens ; 35(3): 232-243, 2022 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-35259237

RESUMEN

Hypertension treatment and control prevent more cardiovascular events than management of other modifiable risk factors. Although the age-adjusted proportion of US adults with controlled blood pressure (BP) defined as <140/90 mm Hg, improved from 31.8% in 1999-2000 to 48.5% in 2007-2008, it remained stable through 2013-2014 and declined to 43.7% in 2017-2018. To address the rapid decline in hypertension control, the National Heart, Lung, and Blood Institute and the Division for Heart Disease and Stroke Prevention of the Centers for Disease Control and Prevention convened a virtual workshop with multidisciplinary national experts. Also, the group sought to identify opportunities to reverse the adverse trend and further improve hypertension control. The workshop immediately preceded the Surgeon General's Call to Action to Control Hypertension, which recognized a stagnation in progress with hypertension control. The presentations and discussions included potential reasons for the decline and challenges in hypertension control, possible "big ideas," and multisector approaches that could reverse the current trend while addressing knowledge gaps and research priorities. The broad set of "big ideas" was comprised of various activities that may improve hypertension control, including: interventions to engage patients, promotion of self-measured BP monitoring with clinical support, supporting team-based care, implementing telehealth, enhancing community-clinical linkages, advancing precision population health, developing tailored public health messaging, simplifying hypertension treatment, using process and outcomes quality metrics to foster accountability and efficiency, improving access to high-quality health care, addressing social determinants of health, supporting cardiovascular public health and research, and lowering financial barriers to hypertension control.


Asunto(s)
Hipertensión , National Heart, Lung, and Blood Institute (U.S.) , Adulto , Presión Sanguínea , Determinación de la Presión Sanguínea , Centers for Disease Control and Prevention, U.S. , Humanos , Hipertensión/diagnóstico , Hipertensión/prevención & control , Estados Unidos/epidemiología
9.
Am J Hypertens ; 35(3): 244-255, 2022 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-35259238

RESUMEN

Hypertension is highly prevalent in the United States, and many persons with hypertension do not have controlled blood pressure. Self-measured blood pressure monitoring (SMBP), when combined with clinical support, is an evidence-based strategy for lowering blood pressure and improving control in persons with hypertension. For years, there has been support for widespread implementation of SMBP by national organizations and the federal government, and SMBP was highlighted as a primary intervention in the 2020 Surgeon General's Call to Action to Control Hypertension, yet optimal SMBP use remains low. There are well-known patient and clinician barriers to optimal SMBP documented in the literature. We explore additional high-level barriers that have been encountered, as broad policy and systems-level changes have been attempted, and offer potential solutions. Collective efforts could modernize data transfer and processing, improve broadband access, expand device coverage and increase affordability, integrate SMBP into routine care and reimbursement practices, and strengthen patient engagement, trust, and access.


Asunto(s)
Determinación de la Presión Sanguínea , Hipertensión , Presión Sanguínea/fisiología , Monitoreo Ambulatorio de la Presión Arterial , Humanos , Hipertensión/diagnóstico , Hipertensión/epidemiología , Estados Unidos/epidemiología
10.
J Biol Chem ; 297(5): 101283, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34626646

RESUMEN

Ubiquinone (Coenzyme Q) is a vital respiratory cofactor and liposoluble antioxidant. In plants, it is not known how the C-6 hydroxylation of demethoxyubiquinone, the penultimate step in ubiquinone biosynthesis, is catalyzed. The combination of cross-species gene network modeling along with mining of embryo-defective mutant databases of Arabidopsis thaliana identified the embryo lethal locus EMB2421 (At1g24340) as a top candidate for the missing plant demethoxyubiquinone hydroxylase. In marked contrast with prototypical eukaryotic demethoxyubiquinone hydroxylases, the catalytic mechanism of which depends on a carboxylate-bridged di-iron domain, At1g24340 is homologous to FAD-dependent oxidoreductases that instead use NAD(P)H as an electron donor. Complementation assays in Saccharomyces cerevisiae and Escherichia coli demonstrated that At1g24340 encodes a functional demethoxyubiquinone hydroxylase and that the enzyme displays strict specificity for the C-6 position of the benzoquinone ring. Laser-scanning confocal microscopy also showed that GFP-tagged At1g24340 is targeted to mitochondria. Silencing of At1g24340 resulted in 40 to 74% decrease in ubiquinone content and de novo ubiquinone biosynthesis. Consistent with the role of At1g24340 as a benzenoid ring modification enzyme, this metabolic blockage could not be bypassed by supplementation with 4-hydroxybenzoate, the immediate precursor of ubiquinone's ring. Unlike in yeast, in Arabidopsis overexpression of demethoxyubiquinone hydroxylase did not boost ubiquinone content. Phylogenetic reconstructions indicated that plant demethoxyubiquinone hydroxylase is most closely related to prokaryotic monooxygenases that act on halogenated aromatics and likely descends from an event of horizontal gene transfer between a green alga and a bacterium.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Mitocondrias , Oxigenasas de Función Mixta , Filogenia , Ubiquinona , Arabidopsis/enzimología , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Mitocondrias/enzimología , Mitocondrias/genética , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Ubiquinona/genética , Ubiquinona/metabolismo
13.
Neurosci Biobehav Rev ; 127: 808-819, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34098183

RESUMEN

In recent years, there has been increasing attention focused on affective empathy in neurodegenerative disorders (NDs). However, prior studies have identified discrepancies not only between, but sometimes within, specific NDs. These discrepancies may reflect methodological differences in how affective empathy has been operationalized, with three quite distinct approaches to assessment possible (self-report, informant-report and performance-based). Therefore, we conducted the first meta-analytic review of affective empathy in people with NDs, that considered the potential moderating role of measurement type. Across 27 studies that included 1456 people with NDs and 832 controls, the results showed that most NDs are associated with impaired affective empathy, but that the magnitude of these difficulties differs meaningfully across disorders. However, most importantly, the results indicated that measurement type is a critical consideration in this literature, with substantive differences emerging for self- versus informant-rated measures. These results are discussed in relation to their practical implications for clinical assessment, as well as how they help to inform current theoretical understanding of affective empathic processing.


Asunto(s)
Empatía , Enfermedades Neurodegenerativas , Humanos
14.
Circulation ; 143(8): 837-851, 2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33617315

RESUMEN

More than 40 years after the 1978 Bethesda Conference on the Declining Mortality from Coronary Heart Disease provided the scientific community with a blueprint for systematic analysis to understand declining rates of coronary heart disease, there are indications the decline has ended or even reversed despite advances in our knowledge about the condition and treatment. Recent data show a more complex situation, with mortality rates for overall cardiovascular disease, including coronary heart disease and stroke, decelerating, whereas those for heart failure are increasing. To mark the 40th anniversary of the Bethesda Conference, the National Heart, Lung, and Blood Institute and the American Heart Association cosponsored the "Bending the Curve in Cardiovascular Disease Mortality: Bethesda + 40" symposium. The objective was to examine the immediate and long-term outcomes of the 1978 conference and understand the current environment. Symposium themes included trends and future projections in cardiovascular disease (in the United States and internationally), the evolving obesity and diabetes epidemics, and harnessing emerging and innovative opportunities to preserve and promote cardiovascular health and prevent cardiovascular disease. In addition, participant-led discussion explored the challenges and barriers in promoting cardiovascular health across the lifespan and established a potential framework for observational research and interventions that would begin in early childhood (or ideally in utero). This report summarizes the relevant research, policy, and practice opportunities discussed at the symposium.


Asunto(s)
Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/patología , Congresos como Asunto , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/mortalidad , Enfermedad Coronaria/patología , Complicaciones de la Diabetes/epidemiología , Humanos , Morbilidad/tendencias , Obesidad/complicaciones , Obesidad/epidemiología , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/mortalidad , Accidente Cerebrovascular/patología , Tasa de Supervivencia/tendencias , Estados Unidos/epidemiología , Urbanización
16.
J Cardiopulm Rehabil Prev ; 40(5): 290-293, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32868655

RESUMEN

Million Hearts and partners have been committed to raising national cardiac rehabilitation participation rates to a goal of 70%. Quality improvement tools, resources, and surveillance models have been developed in support. Efforts to enhance research programs and collaborative initiatives have created momentum to accelerate implementation of new care models.


Asunto(s)
Rehabilitación Cardiaca , Rehabilitación Cardiaca/normas , Rehabilitación Cardiaca/estadística & datos numéricos , Humanos , Modelos Cardiovasculares , Atención al Paciente , Mejoramiento de la Calidad , Estados Unidos
17.
Circ Cardiovasc Qual Outcomes ; 13(1): e005902, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31931615

RESUMEN

BACKGROUND: Despite cardiac rehabilitation (CR) being shown to improve health outcomes among patients with heart disease, its use has been suboptimal. In response, the Million Hearts Cardiac Rehabilitation Collaborative developed a road map to improve CR use, including increasing participation rates to ≥70% by 2022. This observational study provides current estimates to measure progress and identifies the populations and regions most at risk for CR service underutilization. METHODS AND RESULTS: We identified Medicare fee-for-service beneficiaries who were CR eligible in 2016, and assessed CR participation (≥1 CR session attended), timely initiation (participation within 21 days of event), and completion (≥36 sessions attended) through 2017. Measures were assessed overall, by beneficiary characteristics and geography, and by primary CR-qualifying event type (acute myocardial infarction hospitalization; coronary artery bypass surgery; heart valve repair/replacement; percutaneous coronary intervention; or heart/heart-lung transplant). Among 366 103 CR-eligible beneficiaries, 89 327 (24.4%) participated in CR, of whom 24.3% initiated within 21 days and 26.9% completed CR. Eligibility was highest in the East South Central Census Division (14.8 per 1000). Participation decreased with increasing age, was lower among women (18.9%) compared with men (28.6%; adjusted prevalence ratio: 0.91 [95% CI, 0.90-0.93]) was lower among Hispanics (13.2%) and non-Hispanic blacks (13.6%) compared with non-Hispanic whites (25.8%; adjusted prevalence ratio: 0.63 [0.61-0.66] and 0.70 [0.67-0.72], respectively), and varied by hospital referral region and Census Division (range: 18.6% [East South Central] to 39.1% [West North Central]) and by qualifying event type (range: 7.1% [acute myocardial infarction without procedure] to 55.3% [coronary artery bypass surgery only]). Timely initiation varied by geography and qualifying event type; completion varied by geography. CONCLUSIONS: Only 1 in 4 CR-eligible Medicare beneficiaries participated in CR and marked disparities were observed. Reinforcement of current effective strategies and development of new strategies will be critical to address the noted disparities and achieve the 70% participation goal.


Asunto(s)
Rehabilitación Cardiaca/tendencias , Cardiopatías/rehabilitación , Beneficios del Seguro/tendencias , Medicare/tendencias , Evaluación de Procesos y Resultados en Atención de Salud/tendencias , Cooperación del Paciente , Participación del Paciente/tendencias , Factores de Edad , Anciano , Anciano de 80 o más Años , Bases de Datos Factuales , Determinación de la Elegibilidad/tendencias , Femenino , Disparidades en Atención de Salud/tendencias , Cardiopatías/diagnóstico , Cardiopatías/etnología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores Sexuales , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos/epidemiología
18.
New Phytol ; 226(2): 523-540, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31828801

RESUMEN

Fungal phytopathogens can suppress plant immune mechanisms in order to colonize living host cells. Identifying all the molecular components involved is critical for elaborating a detailed systems-level model of plant infection probing pathogen weaknesses; yet, the hierarchy of molecular events controlling fungal responses to the plant cell is not clear. Here we show how, in the blast fungus Magnaporthe oryzae, terminating rice innate immunity requires a dynamic network of redox-responsive E3 ubiquitin ligases targeting fungal sirtuin 2 (Sir2), an antioxidation regulator required for suppressing the host oxidative burst. Immunoblotting, immunopurification, mass spectrometry and gene functional analyses showed that Sir2 levels responded to oxidative stress via a mechanism involving ubiquitination and three antagonistic E3 ubiquitin ligases: Grr1 and Ptr1 maintained basal Sir2 levels in the absence of oxidative stress; Upl3 facilitated Sir2 accumulation in response to oxidative stress. Grr1 and Upl3 interacted directly with Sir2 in a manner that decreased and scaled with oxidative stress, respectively. Deleting UPL3 depleted Sir2 during growth in rice cells, triggering host immunity and preventing infection. Overexpressing SIR2 in the Δupl3 mutant remediated pathogenicity. Our work reveals how redox-responsive E3 ubiquitin ligases in M. oryzae mediate Sir2 accumulation-dependent antioxidation to modulate plant innate immunity and host susceptibility.


Asunto(s)
Magnaporthe , Oryza , Sirtuinas , Ascomicetos , Proteínas Fúngicas/metabolismo , Interacciones Huésped-Patógeno , Inmunidad Innata , Magnaporthe/metabolismo , Oryza/metabolismo , Oxidación-Reducción , Enfermedades de las Plantas , Inmunidad de la Planta , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo
19.
Trends Cardiovasc Med ; 30(6): 364-374, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31607635

RESUMEN

Despite the premature heart disease mortality rate among adults aged 25-64 decreasing by 70% since 1968, the rate has remained stagnant from 2011 on and, in 2017, still accounted for almost 1-in-5 of all deaths among this age group. Moreover, these overall findings mask important differences and continued disparities observed by demographic characteristics and geography. For example, in 2017, rates were 134% higher among men compared to women and 87% higher among blacks compared to whites, and, while the greatest burden remained in the southeastern US, almost two-thirds of all US counties experienced increasing rates among adults aged 35-64 during 2010-2017. Continued high rates of uncontrolled blood pressure and increasing prevalence of diabetes and obesity pose obstacles for re-establishing a downward trajectory for premature heart disease mortality; however, proven public health and clinical interventions exist that can be used to address these conditions.


Asunto(s)
Cardiopatías/mortalidad , Adulto , Distribución por Edad , Edad de Inicio , Femenino , Cardiopatías/diagnóstico , Cardiopatías/etnología , Cardiopatías/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , Servicios Preventivos de Salud/tendencias , Factores Raciales , Medición de Riesgo , Factores de Riesgo , Conducta de Reducción del Riesgo , Distribución por Sexo , Factores Sexuales , Factores de Tiempo , Estados Unidos/epidemiología
20.
Microbiology (Reading) ; 165(11): 1198-1202, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31517594

RESUMEN

Following penetration, the devastating rice blast fungus Magnaporthe oryzae, like some other important eukaryotic phytopathogens, grows in intimate contact with living plant cells before causing disease. Cell-to-cell growth during this biotrophic growth stage must involve nutrient acquisition, but experimental evidence for the internalization and metabolism of host-derived compounds is exceedingly sparse. This striking gap in our knowledge of the infection process undermines accurate conceptualization of the plant-fungal interaction. Here, through our general interest in Magnaporthe metabolism and with a specific focus on the signalling and redox cofactor nicotinamide adenine dinucleotide (NAD), we deleted the M. oryzae QPT1 gene encoding quinolinate phosphoribosyltransferase, catalyst of the last step in de novo NAD biosynthesis from tryptophan. We show how QPT1 is essential for axenic growth on minimal media lacking nicotinic acid (NA, an importable NAD precursor). However, Δqpt1 mutant strains were fully pathogenic, indicating de novo NAD biosynthesis is dispensable for lesion expansion following invasive hyphal growth in leaf tissue. Because overcoming the loss of de novo NAD biosynthesis in planta can only occur if importable NAD precursors (which solely comprise the NA, nicotinamide and nicotinamide riboside forms of vitamin B3) are accessible, we unexpectedly but unequivocally demonstrate that vitamin B3 can be acquired from the host and assimilated into Magnaporthe metabolism during growth in rice cells. Our results furnish a rare, experimentally determined example of host nutrient acquisition by a fungal plant pathogen and are significant in expanding our knowledge of events at the plant-fungus metabolic interface.


Asunto(s)
Magnaporthe/fisiología , Niacinamida/metabolismo , Oryza/microbiología , Enfermedades de las Plantas/microbiología , Medios de Cultivo/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Interacciones Huésped-Patógeno , Magnaporthe/genética , Magnaporthe/metabolismo , Mutación , NAD/metabolismo , Niacina/metabolismo , Niacinamida/análisis , Oryza/química , Pentosiltransferasa/genética , Pentosiltransferasa/metabolismo , Hojas de la Planta/química , Hojas de la Planta/microbiología
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