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1.
Science ; 385(6708): eado1663, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39088611

RESUMEN

An enduring question in evolutionary biology concerns the degree to which episodes of convergent trait evolution depend on the same genetic programs, particularly over long timescales. In this work, we genetically dissected repeated origins and losses of prickles-sharp epidermal projections-that convergently evolved in numerous plant lineages. Mutations in a cytokinin hormone biosynthetic gene caused at least 16 independent losses of prickles in eggplants and wild relatives in the genus Solanum. Homologs underlie prickle formation across angiosperms that collectively diverged more than 150 million years ago, including rice and roses. By developing new Solanum genetic systems, we leveraged this discovery to eliminate prickles in a wild species and an indigenously foraged berry. Our findings implicate a shared hormone activation genetic program underlying evolutionarily widespread and recurrent instances of plant morphological innovation.


Asunto(s)
Evolución Biológica , Citocininas , Genes de Plantas , Epidermis de la Planta , Solanum , Citocininas/biosíntesis , Citocininas/genética , Evolución Molecular , Mutación , Oryza/genética , Filogenia , Epidermis de la Planta/anatomía & histología , Epidermis de la Planta/genética , Solanum/anatomía & histología , Solanum/genética
2.
Cells ; 13(15)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39120326

RESUMEN

Cholestatic liver diseases, including primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC), result from an impairment of bile flow that leads to the hepatic retention of bile acids, causing liver injury. Until recently, the only approved treatments for PBC were ursodeoxycholic acid (UDCA) and obeticholic acid (OCA). While these therapies slow the progression of PBC in the early stage of the disease, approximately 40% of patients respond incompletely to UDCA, and advanced cases do not respond. UDCA does not improve survival in patients with PSC, and patients often have dose-limiting pruritus reactions to OCA. Left untreated, these diseases can progress to fibrosis and cirrhosis, resulting in liver failure and the need for transplantation. These shortcomings emphasize the urgent need for alternative treatment strategies. Recently, nuclear hormone receptors have been explored as pharmacological targets for adjunct therapy because they regulate enzymes involved in bile acid metabolism and detoxification. In particular, the peroxisome proliferator-activated receptor (PPAR) has emerged as a therapeutic target for patients with PBC or PSC who experience an incomplete response to UDCA. PPARα is predominantly expressed in the liver, and it plays an essential role in the regulation of cytochrome P450 (CYP) and uridine 5'-diphospho-glucuronosyltransferase (UGT) enzymes, both of which are critical enzyme families involved in the regulation of bile acid metabolism and glucuronidation, respectively. Importantly, PPARα agonists, e.g., fenofibrate, have shown therapeutic benefits in reducing elevated markers of cholestasis in patients with PBC and PSC, and elafibranor, the first PPAR (dual α, ß/δ) agonist, has been FDA-approved for the second-line treatment of PBC. Additionally, newer PPAR agonists that target various PPAR isoforms (ß/δ, γ) are under development as an adjunct therapy for PBC or PSC, although their impact on glucuronidation pathways are less characterized. This review will focus on PPAR-mediated bile acid glucuronidation as a therapeutic pathway to improve outcomes for patients with PBC and PSC.


Asunto(s)
Ácidos y Sales Biliares , Humanos , Ácidos y Sales Biliares/metabolismo , Receptores Activados del Proliferador del Peroxisoma/metabolismo , Receptores Activados del Proliferador del Peroxisoma/agonistas , Colestasis/metabolismo , Colestasis/tratamiento farmacológico , Animales , Cirrosis Hepática Biliar/metabolismo , Cirrosis Hepática Biliar/tratamiento farmacológico , Colangitis Esclerosante/tratamiento farmacológico , Colangitis Esclerosante/metabolismo
3.
Sci Total Environ ; 951: 175350, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39117197

RESUMEN

Micro-nanoplastic particulates (MNPs) have been identified in both indoor and outdoor environments. From these real-world exposures, MNPs have been identified in human fluids and organ tissues, including the placenta and breastmilk. Laboratory studies have identified MNPs are capable of crossing the placental barrier and depositing in fetal tissues; however, it remained unclear if MNPs persist in offspring tissues after birth. Six pregnant Sprague-Dawley rats were divided equally into two groups: control and exposed to polyamide-12 (PA-12) MNP aerosols (11.46 ± 3.78 mg/m3) over an average of 4.35 h ± 0.39 for 10 non-consecutive days between gestational day (GD) 6 - GD 19, in our custom rodent exposure chamber, allowing for whole-body inhalation. Two-weeks after delivery in-house, offspring tissues (i.e. lung, liver, kidney, heart, brain) from 1 male and 1 female pup per litter were fixed in 4 % paraformaldehyde, sectioned, stained with hematoxylin and eosin, and assessed using hyperspectral dark-field microscopy. PA-12 MNPs were identified in all offspring tissues of the exposed dams. No MNPs were visualized in control tissues. These findings have important implications for human MNPs translocation, deposition, maternal/fetal health, and the developmental origins of health and disease. Further research is warranted to quantify MNPs mass deposition, biological accumulation, and systemic toxicity.

4.
Curr Biol ; 34(16): R781-R784, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39163840

RESUMEN

Plant-insect interactions can be complex and elusive. A new study shows that sap-feeding herbivores reduce tree emissions of specific volatile organic compounds that attract natural enemies. Sap-feeding insects thereby provide enemy-free space for chewing herbivores living on the same tree.


Asunto(s)
Herbivoria , Insectos , Árboles , Compuestos Orgánicos Volátiles , Animales , Herbivoria/fisiología , Compuestos Orgánicos Volátiles/metabolismo , Insectos/fisiología
5.
Drug Alcohol Depend Rep ; 12: 100258, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39156655

RESUMEN

Individuals within the criminal justice system are at greater risk of substance use-related morbidity and mortality and have substantial healthcare needs. In this quasi-experimental study, we assessed utilization patterns of Massachusetts Medicaid Program (MassHealth) services and associated expenditures among drug court probationers compared to a propensity score-matched sample of traditional court probationers. Risk of reoffending, employment status, age, and living arrangement data were used to calculate propensity scores and match probationers between the two court types, producing a final sample of 271 in each court (N=542). Utilization of services and associated expenditures were analyzed using a two-part model to address the skewed distribution of the data and to control for residual differences after matching from the perspective of the payer (i.e., MassHealth). The largest categories of MassHealth spending were prescription pharmaceuticals, hospital inpatient visits, and physician visits. In the unadjusted analysis, drug court probationers exhibited greater MassHealth services utilization and expenditures than traditional court probationers. However, drug courts enrolled more females, more people at higher risk of reoffending, and more people with opioid use disorders. After controlling for differences between the two court types, the difference in MassHealth services utilization and associated expenditures did not reach statistical significance. Drug court probationers were more likely to engage with healthcare services but did not incur significantly greater expenditures than traditional court probationers after controlling for differences between the samples.

6.
Urol Pract ; : 101097UPJ0000000000000676, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39196730

RESUMEN

INTRODUCTION: Limited information exists regarding the association between resident surgical case experience and subsequent case mix in practice. We compare the case log distribution residents completed during their chief year to those completed by these graduates in their first 2 years in independent practice. METHODS: Resident chief year case logs from 10 institutions were analyzed across 4 categories of index procedures: (1) general urology, (2) endourology, (3) reconstructive urology, and (4) urologic oncology. Current Procedural Terminology codes for associated index procedures were used to query case log data during their first 2 years in practice collected by the American Board of Urology. Interactions were tested between the trends of chief year case logs relative to trends in practice case logs. RESULTS: Amongst 292 residents, a total of 104,827 cases were logged during chief year and 77,976 cases in the first 2 years as an attending. Most cases completed during chief year were in oncology followed by general urology, endourology, and reconstructive urology. As attendings, most cases completed were in general urology, followed by endourology, reconstructive urology, and oncology. Chief year case logs showed decreasing trends in the median number of case logs in reconstructive urology, endourology, and general urology, while case logs in independent practice noted increasing trends in all index procedure categories over time. CONCLUSIONS: Urology residents perform more cases during their chief year compared to their first 2 years of independent practice. Case types completed as chief residents vs subsequent clinical practice also differ significantly. These observations may have implications for residency training, particularly regarding curriculum design.

7.
Br J Clin Pharmacol ; 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39187392

RESUMEN

Adolescent transgender medicine is a growing clinical field. Gender-affirming medications for transgender youth may include gonadotropin-releasing hormone (GnRH) agonists, gender-affirming hormones or both. To evaluate the potential effects of GnRH agonists (puberty suppression) on pharmacokinetic processes for transgender youth, we searched PubMed from inception to May 2024 for publications on the effects of GnRH agonists on drug absorption, distribution, metabolism or excretion for transgender adolescents or effects on hormones (including gonadotropins, adrenal androgens, sex steroids) that are associated with changes in drug metabolism during puberty in the general adolescent population. No publications discussed the effects of GnRH agonist treatment on pharmacokinetic processes for adolescent transgender people. Sixteen publications observed marked decreases in gonadotropins and sex steroids for both adolescent transgender men and adolescent transgender women and slight effects on adrenal androgens. During GnRH agonist treatment, changes in body composition and body shape were greater for adolescent transgender people than for cisgender adolescent people. Further research is needed to better understand the effects of GnRH agonists on drug metabolism and other pharmacokinetic processes for transgender adolescents receiving GnRH agonists and other gender-affirming medications.

8.
Mol Biochem Parasitol ; : 111651, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39181505

RESUMEN

The Leishmania life cycle alternates between promastigotes, found in the sandfly, and amastigotes, found in mammals. When an infected sandfly bites a host, promastigotes are engulfed by phagocytes (i.e., neutrophils, dendritic cells, and macrophages) to establish infection. When these phagocytes die or break down, amastigotes must be re-internalized to survive within the acidic phagolysosome and establish disease. To define host kinase regulators of Leishmania promastigote and amastigote uptake and survival within macrophages, we performed an image-based kinase regression screen using a panel of 38 kinase inhibitors with unique yet overlapping kinase targets. We also targeted inert beads to complement receptor 3 (CR3) or Fcγ receptors (FcR) as controls by coating them with complement/C3bi or IgG respectively. Through this approach, we identified several putative host kinases that regulate receptor-mediated phagocytosis and/or the uptake of L. amazonensis. Findings included kinases previously implicated in Leishmania uptake (such as Src family kinases (SFK), Abl family kinases (ABL1/c-Abl, ABL2/Arg), and spleen tyrosine kinase (SYK)), but we also uncovered many novel kinases. Our methods also predicted host kinases necessary for promastigotes to convert to amastigotes or for amastigotes to survive within macrophages. Overall, our results suggest that the concerted action of multiple interconnected networks of host kinases are needed over the course of Leishmania infection, and that the kinases required for the parasite's life cycle may differ substantially depending on which receptors are bound and the life cycle stage that is internalized. In addition, using our screen, we identified kinases that appear to preferentially regulate the uptake of parasites over beads, indicating that the methods required for Leishmania to be internalized by macrophages may differ significantly from generalized phagocytic mechanisms. Our findings are intended to be used as a hypothesis generation resource for the broader scientific community studying the roles of kinases in host-pathogen interactions.

9.
Clin Cancer Res ; 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39196581

RESUMEN

Neurofibromatosis type 1 (NF1), Noonan syndrome and related syndromes, grouped as the RASopathies, result from dysregulation of the RAS-MAPK pathway and demonstrate varied multisystemic clinical phenotypes. Together the RASopathies are among the more prevalent genetic cancer predisposition syndromes and require nuanced clinical management. When compared to the general population, children with RASopathies are at significantly increased risk of benign and malignant neoplasms. In the last decade, clinical trials have shown that targeted therapies can improve outcomes for low-grade and benign neoplastic lesions but have their own challenges, highlighting the multi-disciplinary care needed for such individuals, specifically those with NF1. This perspective, which originated from the 2023 AACR Childhood Cancer Predisposition Workshop, serves to update pediatric oncologists, neurologists, geneticists, counselors, and other healthcare professionals on revised diagnostic criteria, review previously published surveillance guidelines, and harmonize updated surveillance recommendations for patients with NF1 or RASopathies.

11.
Obesity (Silver Spring) ; 32(8): 1448-1452, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38979671

RESUMEN

OBJECTIVE: This study aimed to determine a dopaminergic circuit required for diet-induced obesity in mice. METHODS: We created conditional deletion mutants for tyrosine hydroxylase (TH) using neurotensin receptor 1 (Ntsr1) Cre and other Cre drivers and measured feeding and body weight on standard and high-fat diets. We then used an adeno-associated virus to selectively restore TH to the ventral tegmental area (VTA) Ntsr1 neurons in conditional knockout (cKO) mice. RESULTS: Mice with cKO of Th using Vglut2-Cre, Cck-Cre, Calb1-Cre, and Bdnf-Cre were susceptible to obesity on a high-fat diet; however, Ntsr1-Cre Th cKO mice resisted weight gain on a high-fat diet and did not experience an increase in day eating unlike their wild-type littermate controls. Restoration of TH to the VTA Ntsr1 neurons of the Ntsr1-Cre Th cKO mice using an adeno-associated virus resulted in an increase in weight gain and day eating on a high-fat diet. CONCLUSIONS: Ntsr1-Cre Th cKO mice failed to increase day eating on a high-fat diet, offering a possible explanation for their resistance to diet-induced obesity. These results implicate VTA Ntsr1 dopamine neurons as promoting out-of-phase feeding behavior on a high-fat diet that could be an important contributor to diet-induced obesity in humans.


Asunto(s)
Dieta Alta en Grasa , Dopamina , Ratones Noqueados , Obesidad , Receptores de Neurotensina , Tirosina 3-Monooxigenasa , Área Tegmental Ventral , Aumento de Peso , Animales , Receptores de Neurotensina/metabolismo , Receptores de Neurotensina/genética , Obesidad/metabolismo , Obesidad/etiología , Ratones , Área Tegmental Ventral/metabolismo , Dopamina/metabolismo , Tirosina 3-Monooxigenasa/metabolismo , Masculino , Neuronas/metabolismo , Neuronas Dopaminérgicas/metabolismo , Ratones Endogámicos C57BL , Dependovirus/genética , Peso Corporal
12.
J Affect Disord ; 362: 835-842, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39032715

RESUMEN

INTRODUCTION: Prominent theories of nonsuicidal self-injury (NSSI) propose that the behaviour is characterised by amplified emotional responses. However, little is known about how people who self-injure respond during emotional challenge. METHODS: We measured subjective and physiological responding (heart rate, heart rate variability, and electrodermal responding) among young adults with past-year NSSI (n = 51) and those with no lifetime NSSI (n = 50) during a resting baseline, a stress induction, and a post-stress resting phase. Participants reported the extent to which they spontaneously used cognitive reappraisal and expressive suppression during the post-stress phase. Two weeks later, a subset of the sample (n = 42) reported how they remembered feeling during the laboratory session. RESULTS: Although the NSSI group reported considerably greater emotion dysregulation than Controls, both groups showed similar subjective and psychological reactivity to, and recovery from, emotional challenge. Both groups used reappraisal and suppression regulation strategies following acute stress to a similar extent, and later came to remember the emotional challenge in a similar manner. LIMITATIONS: Within the NSSI group, past-year self-injury tended to be infrequent and sporadic. Only 43.6% of the sample participated in the follow-up survey assessing memory of emotional challenge. CONCLUSIONS: Findings demonstrate that the role of emotion in NSSI is more complex than prominent theories can account for, raising substantial questions regarding the nature of emotion in NSSI. A more comprehensive understanding of the role of emotion in NSSI is needed to inform intervention strategies to better support people who self-injure.


Asunto(s)
Emociones , Respuesta Galvánica de la Piel , Frecuencia Cardíaca , Autoinforme , Conducta Autodestructiva , Humanos , Conducta Autodestructiva/psicología , Conducta Autodestructiva/fisiopatología , Femenino , Masculino , Adulto Joven , Frecuencia Cardíaca/fisiología , Emociones/fisiología , Adulto , Respuesta Galvánica de la Piel/fisiología , Regulación Emocional/fisiología , Estrés Psicológico/psicología , Estrés Psicológico/fisiopatología , Adolescente
13.
mBio ; 15(8): e0072724, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-38975793

RESUMEN

Toxoplasma gondii, the causative agent of toxoplasmosis, is an obligate intracellular parasite that infects warm-blooded vertebrates across the world. In humans, seropositivity rates of T. gondii range from 10% to 90% across communities. Despite its prevalence, few studies address how T. gondii infection changes the metabolism of host cells. In this study, we investigate how T. gondii manipulates the host cell metabolic environment by monitoring the metabolic response over time using noninvasive autofluorescence lifetime imaging of single cells, metabolite analysis, extracellular flux analysis, and reactive oxygen species (ROS) production. Autofluorescence lifetime imaging indicates that infected host cells become more oxidized and have an increased proportion of bound NAD(P)H compared to uninfected controls. Over time, infected cells also show decreases in levels of intracellular glucose and lactate, increases in oxygen consumption, and variability in ROS production. We further examined changes associated with the pre-invasion "kiss and spit" process using autofluorescence lifetime imaging, which also showed a more oxidized host cell with an increased proportion of bound NAD(P)H over 48 hours compared to uninfected controls, suggesting that metabolic changes in host cells are induced by T. gondii kiss and spit even without invasion.IMPORTANCEThis study sheds light on previously unexplored changes in host cell metabolism induced by T. gondii infection using noninvasive, label-free autofluorescence imaging. In this study, we use optical metabolic imaging (OMI) to measure the optical redox ratio (ORR) in conjunction with fluorescence lifetime imaging microscopy (FLIM) to noninvasively monitor single host cell response to T. gondii infection over 48 hours. Collectively, our results affirm the value of using autofluorescence lifetime imaging to noninvasively monitor metabolic changes in host cells over the time course of a microbial infection. Understanding this metabolic relationship between the host cell and the parasite could uncover new treatment and prevention options for T. gondii infections worldwide.


Asunto(s)
Imagen Óptica , Especies Reactivas de Oxígeno , Toxoplasma , Toxoplasma/metabolismo , Imagen Óptica/métodos , Humanos , Especies Reactivas de Oxígeno/metabolismo , Toxoplasmosis/metabolismo , Toxoplasmosis/parasitología , Animales , NADP/metabolismo , Oxidación-Reducción , Glucosa/metabolismo , Interacciones Huésped-Parásitos
14.
Cult Health Sex ; : 1-15, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39041302

RESUMEN

Mothers living with HIV are faced with managing their own complex healthcare and wellness needs while caring for their children. Understanding the lived experiences of mothers living with HIV, including grandmothers and mothers with older children - who are less explicitly represented in existing literature, may guide the development of interventions that best support them and their families. This study sought to explore the role of motherhood and related social/structural factors on engagement with HIV care, treatment-seeking behaviour, and overall HIV management among mothers living with HIV in the USA to inform such efforts. Semi-structured interviews were conducted between June and December 2015 with 52 mothers living with HIV, recruited from the Women's Interagency HIV Study (WIHS) sites in four US cities. Five broad themes were identified from the interviews: children as a motivation for optimal HIV management; children as providing logistical support for HIV care and treatment; the importance of social support for mothers; stressors tied to responsibilities of motherhood; and stigma about being a mother living with HIV. Findings underscore the importance of considering the demands of motherhood when developing more effective strategies to support mothers in managing HIV and promoting the overall health and well-being of their families.

15.
J Adolesc Health ; 75(3): 516-518, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39001752

RESUMEN

PURPOSE: To understand if and why guardians access their adolescent child's electronic health record patient portal account. METHODS: Guardians of transgender and gender-diverse adolescents completed a survey regarding patient portal use. Descriptive statistics were used to describe items related to guardian access to adolescent portal accounts. RESULTS: Of 82 respondents, 37.8% indicated they had used their child's login to access the patient portal. Most indicated they accessed their adolescent's account because their child asked them to do so. Other common reasons included being worried they might miss important health information and not realizing there was a difference between patient and proxy accounts. DISCUSSION: Results of this study provide a more detailed understanding regarding guardian access to adolescent patient portals. Findings can be used to inform adolescent patient portal design and enrollment practices that protect adolescent confidentiality.


Asunto(s)
Confidencialidad , Portales del Paciente , Personas Transgénero , Humanos , Adolescente , Personas Transgénero/psicología , Femenino , Masculino , Portales del Paciente/estadística & datos numéricos , Encuestas y Cuestionarios , Tutores Legales , Registros Electrónicos de Salud
17.
Arterioscler Thromb Vasc Biol ; 44(9): 2108-2117, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39051123

RESUMEN

BACKGROUND: Arterial and venous cardiovascular conditions, such as coronary artery disease (CAD), peripheral artery disease (PAD), and venous thromboembolism (VTE), are genetically correlated. Interrogating underlying mechanisms may shed light on disease mechanisms. In this study, we aimed to identify (1) epidemiological and (2) causal, genetic relationships between metabolites and CAD, PAD, and VTE. METHODS: We used metabolomic data from 95 402 individuals in the UK Biobank, excluding individuals with prevalent cardiovascular disease. Cox proportional-hazards models estimated the associations of 249 metabolites with incident disease. Bidirectional 2-sample Mendelian randomization (MR) estimated the causal effects between metabolites and outcomes using genome-wide association summary statistics for metabolites (n=118 466 from the UK Biobank), CAD (n=184 305 from CARDIoGRAMplusC4D 2015), PAD (n=243 060 from the Million Veterans Project), and VTE (n=650 119 from the Million Veterans Project). Multivariable MR was performed in subsequent analyses. RESULTS: We found that 196, 115, and 74 metabolites were associated (P<0.001) with CAD, PAD, and VTE, respectively. Further interrogation of these metabolites with MR revealed 94, 34, and 9 metabolites with potentially causal effects on CAD, PAD, and VTE, respectively. There were 21 metabolites common to CAD and PAD and 4 common to PAD and VTE. Many putatively causal metabolites included lipoprotein traits with heterogeneity across different sizes and lipid subfractions. Small VLDL (very-low-density lipoprotein) particles increased the risk for CAD while large VLDL particles decreased the risk for VTE. We identified opposing directions of CAD and PAD effects for cholesterol and triglyceride concentrations within HDLs (high-density lipoproteins). Subsequent sensitivity analyses including multivariable MR revealed several metabolites with robust, potentially causal effects of VLDL particles on CAD. CONCLUSIONS: While common vascular conditions are associated with overlapping metabolomic profiles, MR prioritized the role of specific lipoprotein species for potential pharmacological targets to maximize benefits in both arterial and venous beds.


Asunto(s)
Enfermedad de la Arteria Coronaria , Análisis de la Aleatorización Mendeliana , Metabolómica , Enfermedad Arterial Periférica , Tromboembolia Venosa , Humanos , Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/genética , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad Arterial Periférica/epidemiología , Enfermedad Arterial Periférica/diagnóstico , Enfermedad Arterial Periférica/sangre , Enfermedad Arterial Periférica/genética , Tromboembolia Venosa/sangre , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/genética , Masculino , Femenino , Persona de Mediana Edad , Factores de Riesgo , Anciano , Medición de Riesgo , Estudio de Asociación del Genoma Completo , Reino Unido/epidemiología
18.
Cell Rep ; 43(8): 114552, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39068660

RESUMEN

The non-essential amino acid serine is a critical nutrient for cancer cells due to its diverse biosynthetic functions. While some tumors can synthesize serine de novo, others are auxotrophic and therefore reliant on serine uptake. Importantly, despite several transporters being known to be capable of transporting serine, the transporters that mediate serine uptake in cancer cells are not known. Here, we characterize the amino acid transporter ASCT2 (SLC1A5) as a major contributor to serine uptake in cancer cells. ASCT2 is well known as a glutamine transporter in cancer, and our work demonstrates that serine and glutamine compete for uptake through ASCT2. We further show that ASCT2-mediated serine uptake is essential for purine nucleotide biosynthesis and that estrogen receptor α (ERα) promotes serine uptake by directly activating SLC1A5 transcription. Collectively, our work defines an additional important role for ASCT2 as a serine transporter in cancer and evaluates ASCT2 as a potential therapeutic target.


Asunto(s)
Sistema de Transporte de Aminoácidos ASC , Antígenos de Histocompatibilidad Menor , Serina , Sistema de Transporte de Aminoácidos ASC/metabolismo , Sistema de Transporte de Aminoácidos ASC/genética , Humanos , Serina/metabolismo , Antígenos de Histocompatibilidad Menor/metabolismo , Antígenos de Histocompatibilidad Menor/genética , Glutamina/metabolismo , Línea Celular Tumoral , Receptor alfa de Estrógeno/metabolismo , Neoplasias/metabolismo , Neoplasias/patología , Neoplasias/genética , Animales , Transporte Biológico , Femenino , Células MCF-7
19.
Stroke ; 55(8): 2045-2054, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39038097

RESUMEN

BACKGROUND: Individuals who have experienced a stroke, or transient ischemic attack, face a heightened risk of future cardiovascular events. Identification of genetic and molecular risk factors for subsequent cardiovascular outcomes may identify effective therapeutic targets to improve prognosis after an incident stroke. METHODS: We performed genome-wide association studies for subsequent major adverse cardiovascular events (MACE; ncases=51 929; ncontrols=39 980) and subsequent arterial ischemic stroke (AIS; ncases=45 120; ncontrols=46 789) after the first incident stroke within the Million Veteran Program and UK Biobank. We then used genetic variants associated with proteins (protein quantitative trait loci) to determine the effect of 1463 plasma protein abundances on subsequent MACE using Mendelian randomization. RESULTS: Two variants were significantly associated with subsequent cardiovascular events: rs76472767 near gene RNF220 (odds ratio, 0.75 [95% CI, 0.64-0.85]; P=3.69×10-8) with subsequent AIS and rs13294166 near gene LINC01492 (odds ratio, 1.52 [95% CI, 1.37-1.67]; P=3.77×10-8) with subsequent MACE. Using Mendelian randomization, we identified 2 proteins with an effect on subsequent MACE after a stroke: CCL27 ([C-C motif chemokine 27], effect odds ratio, 0.77 [95% CI, 0.66-0.88]; adjusted P=0.05) and TNFRSF14 ([tumor necrosis factor receptor superfamily member 14], effect odds ratio, 1.42 [95% CI, 1.24-1.60]; adjusted P=0.006). These proteins are not associated with incident AIS and are implicated to have a role in inflammation. CONCLUSIONS: We found evidence that 2 proteins with little effect on incident stroke appear to influence subsequent MACE after incident AIS. These associations suggest that inflammation is a contributing factor to subsequent MACE outcomes after incident AIS and highlights potential novel targets.


Asunto(s)
Bancos de Muestras Biológicas , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Accidente Cerebrovascular , Veteranos , Humanos , Masculino , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/epidemiología , Femenino , Reino Unido/epidemiología , Persona de Mediana Edad , Anciano , Progresión de la Enfermedad , Polimorfismo de Nucleótido Simple/genética , Accidente Cerebrovascular Isquémico/genética , Accidente Cerebrovascular Isquémico/epidemiología , Factores de Riesgo , Sitios de Carácter Cuantitativo , Biobanco del Reino Unido
20.
Headache ; 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39077877

RESUMEN

OBJECTIVE: To explore hidden Markov models (HMMs) as an approach for defining clinically meaningful headache-frequency-based groups in migraine. BACKGROUND: Monthly headache frequency in patients with migraine is known to vary over time. This variation has not been completely characterized and is not well accounted for in the classification of individuals as having chronic or episodic migraine, a diagnosis with potentially significant impacts on the individual. This study investigated variation in reported headache frequency in a migraine population and proposed a model for classifying individuals by frequency while accounting for natural variation. METHODS: The American Registry for Migraine Research (ARMR) was a longitudinal multisite study of United States adults with migraine. Study participants completed quarterly questionnaires and daily headache diaries. A series of HMMs were fit to monthly headache frequency data calculated from the diary data of ARMR. RESULTS: Changes in monthly headache frequency tended to be small, with 47% of transitions resulting in a change of 0 or 1 day. A substantial portion (24%) of months reflected daily headache with individuals ever reporting daily headache likely to consistently report daily headache. An HMM with four states with mean monthly headache frequency emissions of 3.52 (95% Prediction Interval [PI] 0-8), 10.10 (95% PI 4-17), 20.29 (95% PI 12-28), and constant 28 days/month had the best fit of the models tested. Of sequential month-to-month headache frequency transitions, 12% were across the 15-headache days chronic migraine cutoff. Under the HMM, 38.7% of those transitions involved a change in the HMM state, and the remaining 61.3% of the time, a change in chronic migraine classification was not accompanied by a change in the HMM state. CONCLUSION: A divide between the second and third states of this model aligns most strongly with the current episodic/chronic distinction, although there is a meaningful overlap between the states that supports the need for flexibility. An HMM has appealing properties for classifying individuals according to their headache frequency while accounting for natural variation in frequency. This empirically derived model may provide an informative classification approach that is more stable than the use of a single cutoff value.

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