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1.
BMC Complement Med Ther ; 23(1): 230, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37434218

RESUMEN

BACKGROUND: Many patients with inflammatory bowel disease (IBD) use complementary and alternative medicine (CAM) for disease management. There is, however, a communication gap between patients and healthcare professionals regarding CAM use, where patients are hesitant to disclose CAM use to providers. The purpose of this study was to identify the quantity and assess the quality of CAM recommendations in IBD clinical practice guidelines (CPGs) using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument. METHODS: MEDLINE, EMBASE, and CINAHL were systematically searched from 2011 to 2022 to find CPGs for the treatment and/or management of IBD. The Guidelines International Network (GIN) and National Center for Complementary and Integrative Health (NCCIH) websites were also searched. Eligible CPGs were assessed using the AGREE II instrument. RESULTS: Nineteen CPGs made CAM recommendations for IBD and were included in this review. Average scaled domain percentages of CPGs were as follows (overall CPG, CAM section): scope and purpose (91.5%, 91.5%), clarity of presentation (90.3%, 64.0%), editorial independence (57.0%, 57.0%), stakeholder involvement (56.7%, 27.8%), rigour of development (54.7%, 45.9%), and applicability (14.6%, 2.1%). CONCLUSIONS: The majority of CPGs with CAM recommendations were of low quality and their CAM sections scored substantially lower relative to other therapies in the overall CPG. In future updates, CPGs with low scaled-domain percentages could be improved in accordance with AGREE II and other guideline development resources. Further research investigating how CAM therapies can best be incorporated into IBD CPGs is warranted.


Asunto(s)
Terapias Complementarias , Enfermedades Inflamatorias del Intestino , Humanos , Comunicación , Personal de Salud , Enfermedades Inflamatorias del Intestino/terapia , MEDLINE , Estados Unidos , Guías de Práctica Clínica como Asunto
2.
J Biol Chem ; 299(6): 104708, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37061004

RESUMEN

Physiologic Ca2+ entry via the Mitochondrial Calcium Uniporter (MCU) participates in energetic adaption to workload but may also contribute to cell death during ischemia/reperfusion (I/R) injury. The MCU has been identified as the primary mode of Ca2+ import into mitochondria. Several groups have tested the hypothesis that Ca2+ import via MCU is detrimental during I/R injury using genetically-engineered mouse models, yet the results from these studies are inconclusive. Furthermore, mitochondria exhibit unstable or oscillatory membrane potentials (ΔΨm) when subjected to stress, such as during I/R, but it is unclear if the primary trigger is an excess influx of mitochondrial Ca2+ (mCa2+), reactive oxygen species (ROS) accumulation, or other factors. Here, we critically examine whether MCU-mediated mitochondrial Ca2+ uptake during I/R is involved in ΔΨm instability, or sustained mitochondrial depolarization, during reperfusion by acutely knocking out MCU in neonatal mouse ventricular myocyte (NMVM) monolayers subjected to simulated I/R. Unexpectedly, we find that MCU knockout does not significantly alter mCa2+ import during I/R, nor does it affect ΔΨm recovery during reperfusion. In contrast, blocking the mitochondrial sodium-calcium exchanger (mNCE) suppressed the mCa2+ increase during Ischemia but did not affect ΔΨm recovery or the frequency of ΔΨm oscillations during reperfusion, indicating that mitochondrial ΔΨm instability on reperfusion is not triggered by mCa2+. Interestingly, inhibition of mitochondrial electron transport or supplementation with antioxidants stabilized I/R-induced ΔΨm oscillations. The findings are consistent with mCa2+ overload being mediated by reverse-mode mNCE activity and supporting ROS-induced ROS release as the primary trigger of ΔΨm instability during reperfusion injury.


Asunto(s)
Mitocondrias Cardíacas , Daño por Reperfusión , Ratones , Animales , Especies Reactivas de Oxígeno/metabolismo , Potencial de la Membrana Mitocondrial , Mitocondrias Cardíacas/metabolismo , Isquemia/metabolismo , Daño por Reperfusión/metabolismo , Reperfusión , Calcio/metabolismo
3.
J Pers Soc Psychol ; 121(1): 1-22, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34472949

RESUMEN

We theorized that from the perspective of U.S. Black Americans, a connection to Black ancestry-and the historical hardship associated with that ancestry-plays an important role in racial categorization. We found support for this across six studies. In Studies 1-3, participants categorized targets with Black ancestry and White experiences or targets with White ancestry and Black experiences. U.S. Black Americans' (more than non-Black Americans') racial categorizations were influenced by Black ancestry (more than by White ancestry). In Study 4, we replicated this effect under extreme conditions (e.g., even when targets had Black ancestry and were phenotypically, socially, culturally, self-identified, and advantaged as White for eighty years, U.S. Black Americans categorized them as Black). In Study 5, U.S. Black Americans were more likely than U.S. White Americans to associate their racial ancestry with hardship, and individual differences in those associations predicted the extent to which U.S. Black Americans categorized the target with Black ancestry and White experiences as Black. In Study 6, participants categorized a target with Black ancestry and ancestral hardship (i.e., their ancestors were kidnapped from Africa and experienced slavery) or a target with Black ancestry and ancestral success (i.e., their ancestors immigrated from Africa and experienced upward mobility). U.S. Black Americans (unlike U.S. White Americans) were more identified with the target with ancestral hardship. Collectively, our research suggests that from the perspective of U.S. Black Americans, the collective Black experiences of the past continue to shape the Black collective of the present. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Asunto(s)
Negro o Afroamericano , Población Blanca , África , Humanos , Grupos Raciales , Estados Unidos
4.
Nat Chem Biol ; 17(2): 161-168, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33199912

RESUMEN

The DNA guanine quadruplexes (G4) play important roles in multiple cellular processes, including DNA replication, transcription and maintenance of genome stability. Here, we showed that Yin and Yang 1 (YY1) can bind directly to G4 structures. ChIP-seq results revealed that YY1-binding sites overlap extensively with G4 structure loci in chromatin. We also observed that the dimerization of YY1 and its binding with G4 structures contribute to YY1-mediated long-range DNA looping. Displacement of YY1 from G4 structure sites disrupts substantially the YY1-mediated DNA looping. Moreover, treatment with G4-stabilizing ligands modulates the expression of not only those genes with G4 structures in their promoters, but also those associated with distal G4 structures that are brought to close proximity via YY1-mediated DNA looping. Together, we identified YY1 as a DNA G4-binding protein, and revealed that YY1-mediated long-range DNA looping requires its dimerization and occurs, in part, through its recognition of G4 structure.


Asunto(s)
ADN/química , ADN/genética , G-Cuádruplex , Expresión Génica/genética , Factor de Transcripción YY1/genética , Sitios de Unión , Sistemas CRISPR-Cas , Cromatina/metabolismo , Células HEK293 , Humanos , Regiones Promotoras Genéticas , Unión Proteica , Dedos de Zinc
5.
Mol Nutr Food Res ; 60(2): 369-80, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26555669

RESUMEN

SCOPE: We studied the impact of dietary supplementation with licorice root components on diet-induced obesity, fat accumulation, and hepatic steatosis in ovariectomized C57BL/6 mice as a menopause model. MATERIALS AND METHODS: We evaluated the molecular and physiological effects of dietary licorice root administered to ovariectomized C57BL/6 mice as root powder (LRP), extracts (LRE), or isolated isoliquiritigenin (ILQ) on reproductive (uterus and mammary gland) and nonreproductive tissues important in regulating metabolism (liver, perigonadal, perirenal, mesenteric, and subcutaneous fat). Quantitative outcome measures including body weight, fat distribution (magnetic resonance imaging), food consumption, bone density and weight (Dual-energy X-ray absorptiometry), and gene expression were assessed by the degree of restoration to the preovariectomized health state. We characterized histological (H&E and oil red O staining) and molecular properties (expression of certain disease markers) of these tissues, and correlated these with metabolic phenotype as well as blood levels of bioactives. CONCLUSION: Although LRE and ILQ provided some benefit, LRP was the most effective in reducing body weight gain, overall fat deposition, liver steatosis, and expression of hepatic lipid synthesis genes following ovariectomy. Our data demonstrate that licorice root provided improvement of multiple metabolic parameters under conditions of low estrogen and high-fat diets without stimulating reproductive tissues.


Asunto(s)
Suplementos Dietéticos , Glycyrrhiza/química , Metabolismo de los Lípidos/efectos de los fármacos , Glándulas Mamarias Animales/efectos de los fármacos , Enfermedad del Hígado Graso no Alcohólico/dietoterapia , Absorciometría de Fotón , Animales , Distribución de la Grasa Corporal , Peso Corporal/efectos de los fármacos , Dieta Alta en Grasa/efectos adversos , Femenino , Flavanonas/farmacología , Ratones Endogámicos C57BL , Ovariectomía , Raíces de Plantas/química , Útero/efectos de los fármacos , Aumento de Peso/efectos de los fármacos
6.
Am J Physiol Regul Integr Comp Physiol ; 305(10): R1141-52, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-24049115

RESUMEN

The sensory circumventricular organs (CVOs) are specialized collections of neurons and glia that lie in the midline of the third and fourth ventricles of the brain, lack a blood-brain barrier, and function as chemosensors, sampling both the cerebrospinal fluid and plasma. These structures, which include the organum vasculosum of the lamina terminalis (OVLT), subfornical organ (SFO), and area postrema (AP), are sensitive to changes in sodium concentration but the cellular mechanisms involved remain unknown. Epithelial sodium channel (ENaC)-expressing neurons of the CVOs may be involved in this process. Here we demonstrate with immunohistochemical and in situ hybridization methods that ENaC-expressing neurons are densely concentrated in the sensory CVOs. These neurons become c-Fos activated, a marker for neuronal activity, after various manipulations of peripheral levels of sodium including systemic injections with hypertonic saline, dietary sodium deprivation, and sodium repletion after prolonged sodium deprivation. The increases seen c-Fos activity in the CVOs were correlated with parallel increases in plasma sodium levels. Since ENaCs play a central role in sodium reabsorption in kidney and other epithelia, we present a hypothesis here suggesting that these channels may also serve a related function in the CVOs. ENaCs could be a significant factor in modulating CVO neuronal activity by controlling the magnitude of sodium permeability in neurons. Hence, some of the same circulating hormones controlling ENaC expression in kidney, such as angiotensin II and atrial natriuretic peptide, may coordinate ENaC expression in sensory CVO neurons and could potentially orchestrate sodium appetite, osmoregulation, and vasomotor sympathetic drive.


Asunto(s)
Canales Epiteliales de Sodio/metabolismo , Hipotálamo/citología , Neuronas/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Sodio/farmacología , Órgano Subfornical/citología , Animales , Área Postrema/citología , Canales Epiteliales de Sodio/genética , Femenino , Inmunohistoquímica , Hibridación in Situ , Masculino , Proteínas Proto-Oncogénicas c-fos/genética , Ratas
7.
Mol Pain ; 8: 75, 2012 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-23013719

RESUMEN

BACKGROUND: The Transient Receptor Potential (TRP) ion channel TRPA1 is a key player in pain pathways. Irritant chemicals activate ion channel TRPA1 via covalent modification of N-terminal cysteines. We and others have shown that 15-Deoxy-Δ12, 14-prostaglandin J2 (15d-PGJ2) similarly activates TRPA1 and causes channel-dependent nociception. Paradoxically, 15d-PGJ2 can also be anti-nociceptive in several pain models. Here we hypothesized that activation and subsequent desensitization of TRPA1 in dorsal root ganglion (DRG) neurons underlies the anti-nociceptive property of 15d-PGJ2. To investigate this, we utilized a battery of behavioral assays and intracellular Ca2+ imaging in DRG neurons to test if pre-treatment with 15d-PGJ2 inhibited TRPA1 to subsequent stimulation. RESULTS: Intraplantar pre-injection of 15d-PGJ2, in contrast to mustard oil (AITC), attenuated acute nocifensive responses to subsequent injections of 15d-PGJ2 and AITC, but not capsaicin (CAP). Intraplantar 15d-PGJ2-administered after the induction of inflammation-reduced mechanical hypersensitivity in the Complete Freund's Adjuvant (CFA) model for up to 2 h post-injection. The 15d-PGJ2-mediated reduction in mechanical hypersensitivity is dependent on TRPA1, as this effect was absent in TRPA1 knockout mice. Ca2+ imaging studies of DRG neurons demonstrated that 15d-PGJ2 pre-exposure reduced the magnitude and number of neuronal responses to AITC, but not CAP. AITC responses were not reduced when neurons were pre-exposed to 15d-PGJ2 combined with HC-030031 (TRPA1 antagonist), demonstrating that inhibitory effects of 15d-PGJ2 depend on TRPA1 activation. Single daily doses of 15d-PGJ2, administered during the course of 4 days in the CFA model, effectively reversed mechanical hypersensitivity without apparent tolerance or toxicity. CONCLUSIONS: Taken together, our data support the hypothesis that 15d-PGJ2 induces activation followed by persistent inhibition of TRPA1 channels in DRG sensory neurons in vitro and in vivo. Moreover, we demonstrate novel evidence that 15d-PGJ2 is analgesic in mouse models of pain via a TRPA1-dependent mechanism. Collectively, our studies support that TRPA1 agonists may be useful as pain therapeutics.


Asunto(s)
Nocicepción/efectos de los fármacos , Prostaglandinas/metabolismo , Canales de Potencial de Receptor Transitorio/metabolismo , Animales , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Masculino , Ratones , Ratones Noqueados , Planta de la Mostaza , Aceites de Plantas/farmacología , Prostaglandina D2/análogos & derivados , Prostaglandina D2/farmacología , Canal Catiónico TRPA1 , Canales de Potencial de Receptor Transitorio/genética
8.
Nature ; 478(7367): 132-5, 2011 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-21927003

RESUMEN

Helicases are vital enzymes that carry out strand separation of duplex nucleic acids during replication, repair and recombination. Bacteriophage T7 gene product 4 is a model hexameric helicase that has been observed to use dTTP, but not ATP, to unwind double-stranded (ds)DNA as it translocates from 5' to 3' along single-stranded (ss)DNA. Whether and how different subunits of the helicase coordinate their chemo-mechanical activities and DNA binding during translocation is still under debate. Here we address this question using a single-molecule approach to monitor helicase unwinding. We found that T7 helicase does in fact unwind dsDNA in the presence of ATP and that the unwinding rate is even faster than that with dTTP. However, unwinding traces showed a remarkable sawtooth pattern where processive unwinding was repeatedly interrupted by sudden slippage events, ultimately preventing unwinding over a substantial distance. This behaviour was not observed with dTTP alone and was greatly reduced when ATP solution was supplemented with a small amount of dTTP. These findings presented an opportunity to use nucleotide mixtures to investigate helicase subunit coordination. We found that T7 helicase binds and hydrolyses ATP and dTTP by competitive kinetics such that the unwinding rate is dictated simply by their respective maximum rates V(max), Michaelis constants K(M) and concentrations. In contrast, processivity does not follow a simple competitive behaviour and shows a cooperative dependence on nucleotide concentrations. This does not agree with an uncoordinated mechanism where each subunit functions independently, but supports a model where nearly all subunits coordinate their chemo-mechanical activities and DNA binding. Our data indicate that only one subunit at a time can accept a nucleotide while other subunits are nucleotide-ligated and thus they interact with the DNA to ensure processivity. Such subunit coordination may be general to many ring-shaped helicases and reveals a potential mechanism for regulation of DNA unwinding during replication.


Asunto(s)
Adenosina Trifosfato/metabolismo , Adenosina Trifosfato/farmacología , Bacteriófago T7/enzimología , Biocatálisis/efectos de los fármacos , ADN Helicasas/química , ADN Helicasas/metabolismo , Subunidades de Proteína/metabolismo , Emparejamiento Base/efectos de los fármacos , Unión Competitiva , ADN/química , ADN/metabolismo , ADN Primasa/química , ADN Primasa/metabolismo , Replicación del ADN , ADN de Cadena Simple/química , ADN de Cadena Simple/metabolismo , Hidrólisis/efectos de los fármacos , Cinética , Modelos Biológicos , Desnaturalización de Ácido Nucleico/efectos de los fármacos , Subunidades de Proteína/química , Termodinámica , Nucleótidos de Timina/metabolismo , Nucleótidos de Timina/farmacología
9.
Structure ; 16(2): 280-94, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18275819

RESUMEN

Voltage-gated calcium channels (CaVs) are large, multisubunit complexes that control cellular calcium entry. CaV pore-forming (CaValpha1) and cytoplasmic (CaVbeta) subunits associate through a high-affinity interaction between the CaValpha1 alpha interaction domain (AID) and CaVbeta alpha binding pocket (ABP). Here we analyze AID-ABP interaction thermodynamics using isothermal titration calorimetry. We find that commensurate with their strong sequence similarity, all CaV1 and CaV2 AID peptides bind CaVbeta with similar nanomolar affinities. Although the AID-ABP interface encompasses 24 side chains, alanine-scanning mutagenesis reveals that the binding energy is focused in two complementary hotspots comprising four deeply conserved residues. Electrophysiological experiments show that hotspot interaction disruption prevents trafficking and functional modulation of CaV1.2 by CaVbeta. Together, the data support the primacy of the AID-ABP interface for CaValpha1-CaVbeta association, underscore the idea that hotspots dominate protein-protein interaction affinities, and uncover a target for strategies to control cellular excitability by blocking CaValpha1-CaVbeta complex formation.


Asunto(s)
Canales de Calcio/química , Subunidades de Proteína/química , Alanina/genética , Secuencia de Aminoácidos , Animales , Sitios de Unión , Canales de Calcio/genética , Canales de Calcio/metabolismo , Canales de Calcio Tipo L/química , Canales de Calcio Tipo L/genética , Canales de Calcio Tipo L/metabolismo , Calorimetría , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Mutagénesis , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Estructura Terciaria de Proteína , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Conejos , Ratas , Termodinámica
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