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1.
Genes Dev ; 32(23-24): 1537-1549, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30463901

RESUMEN

Human globin gene production transcriptionally "switches" from fetal to adult synthesis shortly after birth and is controlled by macromolecular complexes that enhance or suppress transcription by cis elements scattered throughout the locus. The DRED (direct repeat erythroid-definitive) repressor is recruited to the ε-globin and γ-globin promoters by the orphan nuclear receptors TR2 (NR2C1) and TR4 (NR2C2) to engender their silencing in adult erythroid cells. Here we found that nuclear receptor corepressor-1 (NCoR1) is a critical component of DRED that acts as a scaffold to unite the DNA-binding and epigenetic enzyme components (e.g., DNA methyltransferase 1 [DNMT1] and lysine-specific demethylase 1 [LSD1]) that elicit DRED function. We also describe a potent new regulator of γ-globin repression: The deubiquitinase BRCA1-associated protein-1 (BAP1) is a component of the repressor complex whose activity maintains NCoR1 at sites in the ß-globin locus, and BAP1 inhibition in erythroid cells massively induces γ-globin synthesis. These data provide new mechanistic insights through the discovery of novel epigenetic enzymes that mediate γ-globin gene repression.


Asunto(s)
Regulación de la Expresión Génica/genética , Co-Represor 1 de Receptor Nuclear/genética , Co-Represor 1 de Receptor Nuclear/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina Tiolesterasa/metabolismo , gamma-Globinas/genética , Sitios de Unión , Línea Celular , Activación Enzimática/genética , Epigénesis Genética/genética , Células Eritroides/metabolismo , Silenciador del Gen , Células HEK293 , Humanos , Células K562 , Miembro 1 del Grupo C de la Subfamilia 2 de Receptores Nucleares/metabolismo , Dominios Proteicos , Receptores de Esteroides/metabolismo , Receptores de Hormona Tiroidea/metabolismo
2.
Br J Haematol ; 204(4): 1422-1428, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38176404

RESUMEN

The standard of care for fit, newly diagnosed multiple myeloma patients includes induction therapy followed by consolidative high-dose chemotherapy with melphalan and autologous stem cell transplant (AHSCT). Intensified preparative regimens, such as busulfan and melphalan (BuMel), have shown promise to lengthen progression-free survival (PFS). We previously reported that the addition of bortezomib to BuMel improved PFS compared to melphalan alone in CIBMTR-matched controls. We now integrate the second-generation protease inhibitor, carfilzomib, before and after BuMel (BuMelCar) in a phase I/II trial with carfilzomib. Patients with NDMM, relapsed/refractory MM (RRMM) and those failing prior AHSCT were eligible. Primary end-points were safety and tolerability. Secondary end-points included minimal residual disease negativity rates, PFS and OS. The study enrolled 19 patients. 73% were high risk either due to R-ISS III status, adverse genetics or relapsed after prior AHSCT. The maximum tolerated dose (MTD) of carfilzomib was determined to be 36 mg/m2. Noted grade 3 toxicities were febrile neutropenia (79%), mucositis (21%) and diarrhoea (16%). The 2-year PFS for the whole cohort and MTD was 89% and 100% respectively. 80% of all patients and 82% of patients in the MTD cohort achieved MRD negativity. Further studies regarding this regimen are planned.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Mieloma Múltiple , Oligopéptidos , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Busulfano , Melfalán , Mieloma Múltiple/tratamiento farmacológico , Trasplante de Células Madre , Trasplante Autólogo
3.
Genome Res ; 31(10): 1885-1899, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33837132

RESUMEN

Auditory hair cells transduce sound to the brain, and in mammals, these cells reside together with supporting cells in the sensory epithelium of the cochlea, called the organ of Corti. To establish the organ's delicate function during development and differentiation, spatiotemporal gene expression is strictly controlled by chromatin accessibility and cell type-specific transcription factors, jointly representing the regulatory landscape. Bulk sequencing technology and cellular heterogeneity obscured investigations on the interplay between transcription factors and chromatin accessibility in inner ear development. To study the formation of the regulatory landscape in hair cells, we collected single-cell chromatin accessibility profiles accompanied by single-cell RNA data from genetically labeled murine hair cells and supporting cells after birth. Using an integrative approach, we predicted cell type-specific activating and repressing functions of developmental transcription factors. Furthermore, by integrating gene expression and chromatin accessibility data sets, we reconstructed gene regulatory networks. Then, using a comparative approach, 20 hair cell-specific activators and repressors, including putative downstream target genes, were identified. Clustering of target genes resolved groups of related transcription factors and was used to infer their developmental functions. Finally, the heterogeneity in the single-cell data allowed us to spatially reconstruct transcriptional as well as chromatin accessibility trajectories, indicating that gradual changes in the chromatin accessibility landscape are lagging behind the transcriptional identity of hair cells along the organ's longitudinal axis. Overall, this study provides a strategy to spatially reconstruct the formation of a lineage-specific regulatory landscape using a single-cell multi-omics approach.


Asunto(s)
Cóclea , Células Ciliadas Auditivas , Animales , Diferenciación Celular , Cromatina/genética , Cromatina/metabolismo , Células Ciliadas Auditivas/metabolismo , Ratones , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
4.
Mol Psychiatry ; 28(1): 127-140, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35999276

RESUMEN

Oxytocin, a neuropeptide known for its role in reproduction and socioemotional processes, may hold promise as a therapeutic agent in treating social impairments in patient populations. However, research has yet to uncover precisely how to manipulate this system for clinical benefit. Moreover, inconsistent use of standardized and validated oxytocin measurement methodologies-including the design and study of hormone secretion and biochemical assays-present unresolved challenges. Human studies measuring peripheral (i.e., in plasma, saliva, or urine) or central (i.e., in cerebrospinal fluid) oxytocin concentrations have involved very diverse methods, including the use of different assay techniques, further compounding this problem. In the present review, we describe the scientific value in measuring human endogenous oxytocin concentrations, common issues in biochemical analysis and study design that researchers face when doing so, and our recommendations for improving studies using valid and reliable methodologies.


Asunto(s)
Neuropéptidos , Oxitocina , Humanos , Saliva/química , Proyectos de Investigación , Plasma/química
5.
Ann Vasc Surg ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38942368

RESUMEN

OBJECTIVES: Low wall shear stress (WSS) is predictive of aortic aneurysm growth and rupture. Yet, estimating WSS in a clinical setting is impractical whereas measuring aneurysm geometry is feasible. This study investigates the association between saccular aneurysm geometry of the infrarenal aorta and WSS. METHODS: Starting with a non- aneurysmal, patient-specific, computational fluid dynamics model of the aorta, saccular aneurysms of varying geometry were created by incrementally increasing the neck width and sac depth from 1cm to 4cm. The aspect ratio (the ratio between sac depth and neck width) varied between 0.25 and 4. The peak WSS, time- averaged WSS (TAWSS), and oscillatory shear index (OSI) were measured within the aneurysm sac. RESULTS: Decreasing the neck width from 4cm to 1cm decreased the peak WSS by 69% and the TAWSS by 83%. Increasing the sac depth from 1cm to 4cm decreased the peak WSS by 55% and OSI by 37%. The aspect ratio was negatively correlated to peak WSS (Rs -0.85, p<0.001). CONCLUSIONS: In saccular aneurysms of the infrarenal aorta, a smaller neck width, deeper aneurysm sac, and larger aspect ratio are associated with lower peak WSS.

6.
Clin Linguist Phon ; : 1-16, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38832412

RESUMEN

Cleft type affects speech outcomes, but exact relationships remain unclear as outcome measures vary. The primary aim was to investigate the relationship between cleft type and speech outcome using different measures in 4-to-6-year-olds with non-syndromic clefts. Secondary aims were to explore the relationships between (i) speech measures used; and (ii) parent perception of speech intelligibility and listener familiarity. Twenty-two pre-schoolers with clefts, plus one parent for each child, were recruited through a hospital outpatient clinic. Children with cleft lip and palate (CLP; n = 11) and those with cleft palate only (CP; n = 11), matched on age and time of palate repair, were compared on Percentage Consonants Correct (PCC), clinician-reported speech intelligibility, and parent rating on the Intelligibility-in-Context Scale (ICS). Children with CLP had significantly lower PCC scores than children with CP (p = .020), but had no significant differences in their clinician- or parent-reported speech intelligibility. Clinician-reported speech intelligibility correlated significantly with both PCC (τ = .594, p < 0.01) and ICS (τ = .424, p = 0.009). No significant correlation was found between PCC and ICS (τ =.197, p = 0.113). Overall, parents rated their child's intelligibility higher for familiar compared to unfamiliar communication partners (τ = 2.325, p = 0.001, r = .76). Cleft type is crucial for intervention planning when objective measures are employed. Speech outcomes should be evaluated at impairment, activity, and participation levels, and by different communication partners, to comprehensively evaluate communicative effectiveness.

7.
J Neurochem ; 164(5): 613-623, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36420597

RESUMEN

While the illicit use and misuse of stimulants like cocaine and methylphenidate (MP) has increased, there remains no FDA-approved treatments for psychostimulant use disorders (PSUD). Oxytocin (OT) has shown promise as a potential pharmacotherapy for PSUD. Dopamine (DA) neurotransmission plays a significant role in PSUD. We have recently shown that OT blunts the reinforcing effects of MP but, surprisingly, enhanced MP-induced stimulation of DA levels. Such effects have been suggested as a result of activation of OT receptors or, alternatively, could be mediated by direct actions of OT on MP blockade of the DA transporter. Here, we employed fast scan cyclic voltammetry (FSCV) to investigate the effects of systemic OT on MP-induced changes in the dynamics of DA, phasic release and uptake, in the nucleus accumbens shell (NAS) of Sprague-Dawley rats. We also tested the systemic effects of an antagonist of OT receptors, atosiban, to counteract the OT enhancement of dopaminergic effects of MP under microdialysis procedures in the NAS in rats. Administration of OT alone (2 mg/kg; i.p.) did not significantly modify evoked NAS DA dynamics measured by FSCV, and when administered 10 min before MP (0.1, 0.3, 1.0 mg/kg; i.v.), OT did not potentiate MP-induced increases in phasic DA release and did not alter DA clearance rate, suggesting no direct interactions of OT with the MP-induced blockade of DA uptake. Also, OT alone did not elicit significant changes in tonic, extracellular NAS DA levels measured by microdialysis. However, consistent with previous studies, we observed that OT pretreatments (2 mg/kg; i.p.) potentiated MP-induced (0.1, 0.3, 1.0 mg/kg; i.v.) efflux of extracellular NAS DA levels. This effect was abolished when rats were pretreated with atosiban (2 mg/kg; i.p.), suggesting that OT receptors mediate this OT action. Overall, our results suggest that OT receptors mediated OT potentiation of MP-induced stimulation of extracellular NAS DA levels, likely driven by modulation of DA receptor signaling pathways, without affecting MP blockade of DAT.


Asunto(s)
Estimulantes del Sistema Nervioso Central , Metilfenidato , Ratas , Animales , Metilfenidato/metabolismo , Metilfenidato/farmacología , Dopamina/metabolismo , Oxitocina/metabolismo , Oxitocina/farmacología , Receptores de Oxitocina/metabolismo , Ratas Sprague-Dawley , Estimulantes del Sistema Nervioso Central/farmacología , Núcleo Accumbens
8.
Am J Med Genet A ; 191(9): 2337-2343, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37435845

RESUMEN

Two children are presented who have a distinct syndrome of multiple buccolingual frenula, a stiff and short fifth finger with small nails, a hypothalamic hamartoma, mild to moderate neurological impairment, and mild endocrinological symptoms. No variant assessed to be pathogenic or likely pathogenic was detected in the GLI3 gene in either child. This syndrome appears to be distinct from the inherited Pallister-Hall syndrome associated with GLI3 variants, which is characterized by hypothalamic hamartoma, mesoaxial polydactyly, and other anomalies. In the individuals described here, manifestations outside of the central nervous system were milder and the mesoaxial polydactyly, which is common in individuals with Pallister-Hall syndrome, was absent. Instead, these children had multiple buccolingual frenula together with the unusual appearance of the fifth digit. It remains unclear whether these two individuals represent a separate nosologic entity or if they represent a milder manifestation of one of the more severe syndromes associated with a hypothalamic hamartoma.


Asunto(s)
Hamartoma , Enfermedades Hipotalámicas , Síndrome de Pallister-Hall , Polidactilia , Niño , Humanos , Síndrome de Pallister-Hall/diagnóstico , Síndrome de Pallister-Hall/genética , Hamartoma/diagnóstico , Hamartoma/genética , Hamartoma/patología , Enfermedades Hipotalámicas/diagnóstico , Enfermedades Hipotalámicas/genética , Enfermedades Hipotalámicas/patología , Polidactilia/genética
9.
J Int Neuropsychol Soc ; 29(7): 670-676, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36154934

RESUMEN

OBJECTIVE: Loss of empathy is a hallmark feature of behavioral variant frontotemporal dementia (bvFTD). Change in socioemotional functioning identified by others is often the primary initial presenting concern in this disorder, in contrast to more subtle early cognitive changes and limited patient insight. The present study examined the predictive utility of an empathy informant-report measure for discriminating clinician-diagnosed bvFTD from other dementia syndromes. METHOD: Data from the National Alzheimer's Coordinating Center (NACC) database were used to study individuals with bvFTD (n = 406) and other dementia syndromes (n = 385). Participants were administered neuropsychological measures and collateral informants completed an informant-report of empathy. RESULTS: Informants reported that patients with bvFTD demonstrated significantly lower levels of empathic concern [F(1, 789) = 120.91, p < .001, η2 = 0.13] and perspective taking [F(1, 789) = 153.08, p < .001, η2 = 0.16] than patients with other dementia syndromes. These differences were not attributable to the level of global cognitive impairment. Empathy scores were not significantly associated with any neurocognitive measure when controlling for age. ROC curve analyses showed fair to good clinical utility of the informant-report empathy measure for distinguishing bvFTD from non-bvFTD, whereas a traditional measure of executive functioning failed to differentiate the groups. CONCLUSIONS: These findings indicate that informant ratings of empathy offer a unique source of clinical information that may be useful in detecting neurobehavioral changes specific to bvFTD before a clear neurocognitive pattern emerges on testing.


Asunto(s)
Enfermedad de Alzheimer , Demencia Frontotemporal , Humanos , Empatía , Demencia Frontotemporal/complicaciones , Diagnóstico Diferencial , Síndrome , Pruebas Neuropsicológicas , Enfermedad de Alzheimer/diagnóstico
10.
BMC Vet Res ; 19(1): 198, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37817164

RESUMEN

BACKGROUND: Polyautoimmunity is the expression of more than one autoimmune disease in a single patient. This report documents polyautoimmunity in a mixed breed dog with concurrent uveitis, cutaneous depigmentation, and inflammatory myopathy. CASE PRESENTATION: A 1-year-old male neutered mixed breed dog was presented for progressive generalized leukotrichia and leukoderma, bilateral panuveitis, and masticatory muscle atrophy. The latter progressed to myositis of lingual, pharyngeal, and masticatory muscles confirmed by biopsy. Temporalis muscle was completely replaced by adipose and fibrous tissue, and necrotic myofibers with extensive infiltration of mononuclear cells indicated active myositis of lingual muscle. Skin biopsies showed severe melanin clumping in epidermis, hair follicles, and hair shafts, and perifollicular pigmentary incontinence. Uveitis, depigmentation, and myositis affecting the masticatory, pharyngeal, and tongue muscles were diagnosed based on clinical, histological, and laboratory findings. CONCLUSIONS: To the authors' knowledge, this is the first report of concurrent uveitis, progressive cutaneous depigmentation, and inflammatory myopathy in a dog.


Asunto(s)
Enfermedades Autoinmunes , Enfermedades de los Perros , Miositis , Uveítis , Síndrome Uveomeningoencefálico , Animales , Perros , Masculino , Enfermedades Autoinmunes/veterinaria , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/patología , Miositis/veterinaria , Miositis/complicaciones , Piel/patología , Uveítis/veterinaria , Síndrome Uveomeningoencefálico/diagnóstico , Síndrome Uveomeningoencefálico/etiología , Síndrome Uveomeningoencefálico/patología , Síndrome Uveomeningoencefálico/veterinaria
11.
Eur J Pediatr ; 182(6): 2903-2911, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37059961

RESUMEN

Current American Academy of Pediatrics (AAP) Guidelines recommend monitoring thyroid function in infants with Down syndrome (DS) at birth, 6 and 12 months, and annually thereafter. This study aimed to determine whether these guidelines are optimal for early diagnosis and treatment of (subclinical) hypothyroidism. Enrolled infants with DS less than age 7 months, born at ≥ 30 weeks gestation to monitor thyroid function test (TFT). A filter paper (FP) blood sample was analyzed for TSH and total T4 at ages 2 and 4 weeks and monthly thereafter until 12 months. Subjects with abnormal FP sample and confirmatory serum TFT for hypothyroidism promptly started treatment. Subjects with thyroid dysfunction identified had thyroid antibodies measured at diagnosis and 12 months. Descriptive statistics determined average time to diagnosis of abnormal TFT. Sixteen (30%) of 54 subjects were diagnosed with a thyroid disorder, the majority with subclinical hypothyroidism (SH) and 1 with hyperthyroidism. Diagnosis occurred in 6 (11%), 9 (17%), and 12 (22.2%) infants in the first 30, 60, and 90 days of life (DOL), respectively. Eight infants had an abnormal NBS and half were diagnosed with a thyroid disorder by DOL 8 and the remainder prior to 4 months. Among subjects with a normal NBS, four were diagnosed at a mean of 104 days and three at a mean of 101 days prior to the 6-month and 12-month routine screens, respectively.  Conclusion: Based on current AAP guidelines, thyroid disorder diagnosis would have been delayed in nearly 20% of the subjects. An additional TFT screen at 1 and 3 months can lead to earlier diagnosis and treatment. What is Known: • Current American Academy of Pediatrics (AAP) Guidelines recommend thyroid function tests (TFT) in infants with Down syndrome (DS) at birth and 6 and 12 months. • Peer- reviewed retrospective studies report an increased incidence of hypothyroidism in infants with DS undetected by the newborn screen (NBS) and prior to 6 months. What is New: • This prospective study monitored TFT in infants with DS at age 2 weeks and monthly throughout the first year of life. • The findings in this study support additional TFT screens at 1 and 3 months in infants with DS.


Asunto(s)
Hipotiroidismo Congénito , Síndrome de Down , Hipotiroidismo , Enfermedades de la Tiroides , Recién Nacido , Lactante , Humanos , Niño , Síndrome de Down/complicaciones , Síndrome de Down/diagnóstico , Estudios Prospectivos , Estudios Retrospectivos , Hipotiroidismo/complicaciones , Hipotiroidismo/diagnóstico , Enfermedades de la Tiroides/complicaciones , Enfermedades de la Tiroides/diagnóstico , Pruebas de Función de la Tiroides , Tirotropina , Tiroxina , Hipotiroidismo Congénito/diagnóstico
12.
Addict Biol ; 28(5): e13274, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37186442

RESUMEN

Early life adversity (ELA) has long-lasting and potentially harmful effects on adult mental and physical health, including a higher likelihood of developing psychiatric conditions such as depression, anxiety and alcohol use disorder (AUD). It has been suggested that inflammation may play a role in linking ELA to the development of AUD. Here, we evaluated a number of predictive factors of high sensitivity C-reactive protein (hsCRP), a key inflammatory marker, and the potential mediating role of hsCRP in the relationship between ELA and alcohol misuse in adulthood. Data was collected from participants who participated in NIAAA screening protocols between January 2013 and December 2019. In this secondary analysis, we first tested, via multiple linear regression, potential predictors of hsCRP levels among adults with AUD (N = 781) and non-AUD (N = 440) individuals. We subsequently conducted mediation analyses to evaluate the potential role of hsCRP in the relationship between early life stress and alcohol use. Regression analysis showed that stress in early life, but not childhood trauma, significantly predicted increased hsCRP levels in adulthood (p < 0.05). Additionally, a greater amount of alcohol drinking, but not a diagnosis of AUD, significantly predicted increased hsCRP levels (p < 0.05). Furthermore, hsCRP mediated the relationship between early life stress and alcohol consumption. Early life stress and heavier alcohol drinking both predicted increased hsCRP levels; however, an AUD diagnosis did not. Elevated inflammation, due to and/or predicted by greater early life stress, may contribute to the development of unhealthy alcohol use in adulthood.


Asunto(s)
Experiencias Adversas de la Infancia , Alcoholismo , Adulto , Humanos , Proteína C-Reactiva/metabolismo , Inflamación , Alcoholismo/epidemiología , Alcoholismo/psicología , Consumo de Bebidas Alcohólicas
13.
Mol Cell Neurosci ; 120: 103736, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35577314

RESUMEN

The sensory cells of the inner ear, called hair cells, do not regenerate spontaneously and therefore, hair cell loss and subsequent hearing loss are permanent in humans. Conversely, functional hair cell regeneration can be observed in non-mammalian vertebrate species like birds and fish. Also, during postnatal development in mice, limited regenerative capacity and the potential to isolate stem cells were reported. Together, these findings spurred the interest of current research aiming to investigate the endogenous regenerative potential in mammals. In this review, we summarize current in vitro based approaches and briefly introduce different in vivo model organisms utilized to study hair cell regeneration. Furthermore, we present an overview of the findings that were made synergistically using both, the in vitro and in vivo based tools.


Asunto(s)
Oído Interno , Pérdida Auditiva , Animales , Oído Interno/fisiología , Células Ciliadas Auditivas/fisiología , Pérdida Auditiva/terapia , Mamíferos , Ratones , Células Madre
14.
J Interprof Care ; 37(1): 1-10, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35285379

RESUMEN

In healthcare settings, speaking up is considered essential for patient safety. Indeed, voice opportunities are widely available mandatory mechanisms for speaking up at the routine interprofessional team meetings of our study site. Yet, healthcare professionals in team meetings often do not go beyond straightforward reporting of test results and biomedical-functional parameters, suggesting that members with psycho-social information related to the patient are not participating fully in team meetings. Post-meeting interviews with some of the team members revealed the moments of silence and the ideological contradictions underlying team discussions. We explored silences and contradictions as argumentative meanings inherent in naturally occurring speech. The identification of opposing meanings tells of ideological dilemmas that may explain why healthcare practitioners do not speak up vigorously. We identified three such dilemmas: the ideology of working in teams versus the ideology of working solo; the ideology of autonomy versus the ideology of paternalism; and the ideology of collectivism versus the ideology of individuality. The dilemmas made visible the dimensions of silence as well as silencing as an imposition of silence from above. We suggest focussing on mapping disciplinary and interpretive differences and their effects amongst team members may motivate voice. Further studies should explore the affective dimensions of silence in interprofessional team meetings.


Asunto(s)
Personal de Salud , Relaciones Interprofesionales , Humanos , Personal de Salud/psicología , Atención a la Salud , Seguridad del Paciente , Grupo de Atención al Paciente
15.
Hum Reprod ; 37(4): 848-858, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35038334

RESUMEN

STUDY QUESTION: Are peripubertal blood lead levels (BLLs) associated with semen parameters and serum reproductive hormones among young Russian men? SUMMARY ANSWER: We observed a suggestion of lower ejaculate volume with higher peripubertal BLL but no associations of BLLs with reproductive hormones measured throughout adolescence or with other sperm parameters measured at adulthood. WHAT IS KNOWN ALREADY: Lead is a known reproductive toxicant and endocrine disruptor. Previous literature has shown associations between high lead exposure and poorer semen quality both in occupationally and environmentally exposed men. However, to our knowledge, no longitudinal studies have explored the association of childhood lead exposure with semen parameters and reproductive hormones in young men. STUDY DESIGN, SIZE, DURATION: The Russian Children's Study is a prospective cohort study that enrolled 516 boys at age 8-9 years in 2003-2005 and followed them annually for 10 years. BLLs were measured at entry and lifestyle and health questionnaires were completed. Reproductive hormones were measured in blood samples collected every 2 years. PARTICIPANTS/MATERIALS, SETTING, METHODS: Among the 516 boys enrolled, 481 had BLLs measured at entry. Of these, 453 had at least one measurement of serum testosterone, follicle stimulating hormone (FSH) or luteinizing hormone (LH) (median = 5 samples per boy) and 223 had semen samples collected ∼10 years after enrolment. Semen assessment included ejaculated volume, sperm concentration, progressive motility and total sperm count, and parameters were categorized using published andrology standards for low semen quality based on sperm count and motility. Linear mixed models were used to examine the associations of log-transformed BLLs (and BLL categories) with reproductive hormones and semen parameters, adjusting for potential confounders. MAIN RESULTS AND THE ROLE OF CHANCE: Among the 223 young men with peripubertal BLLs and at least one semen sample (total samples = 438), the median (interquartile range) BLL was 3 (2, 5) µg/dl and 27% had BLL ≥5 µg/dl. Overall, 49% of the semen samples fell below reference levels for sperm count and/or motility. Men with peripubertal BLL ≥5 µg/dl had significantly lower ejaculated volume than those with BLL <5 µg/dl (mean = 2.42 vs 2.89 ml, P = 0.02), but this difference was attenuated in adjusted models (mean = 2.60 vs 2.83 ml, P = 0.25). No associations were observed between BLL measured at age 8-9 years and reproductive hormone levels or sperm parameters, including sperm concentration, total count, progressive motility and total progressive motile sperm count, or with the probability of having low semen quality based on sperm count/motility. LIMITATIONS, REASONS FOR CAUTION: Only a subset of the original cohort participated in the semen quality portion of the study, although inverse probability weighting was used to account for possible selection bias. BLLs were only measured at a single time in peripuberty, and other exposure time periods, including later or longer-term childhood exposure, may be more predictive of semen quality. The young men were also exposed to other chemical contaminants before and during pubertal development. WIDER IMPLICATIONS OF THE FINDINGS: While semen volume often receives less attention than other sperm parameters, it is an important component of male fertility. Additional prospective studies covering different exposure windows and including other seminal plasma biomarkers are warranted to explore our finding of potentially lower ejaculated volume with higher BLLs and to confirm the lack of associations for other semen parameters among youth exposed to environmental BLLs. STUDY FUNDING/COMPETING INTEREST(S): Funding was provided through grants R01ES0014370 and P30ES000002 from the National Institute of Environmental Health Sciences, grant R82943701 from the U.S. Environmental Protection Agency, and grant 18-15-00202 from the Russian Science Foundation (O.S and Y.D.). All authors report no competing interests. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Plomo , Semen , Adolescente , Adulto , Niño , Estudios de Cohortes , Humanos , Hormona Luteinizante , Masculino , Estudios Prospectivos , Análisis de Semen , Recuento de Espermatozoides , Motilidad Espermática
16.
Mol Psychiatry ; 26(2): 545-555, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-30382188

RESUMEN

Previous studies suggest that GABA-B receptor agonism may represent an effective pharmacological approach to treat addictive disorders. Baclofen is a selective GABA-B receptor agonist which has been investigated as a potential treatment for alcohol use disorder. However, research is needed to understand the biobehavioral mechanisms underlying baclofen's effect on alcohol use. In the present randomized, double-blind, placebo-controlled study, thirty-four alcohol-dependent individuals were randomized to receive baclofen (30 mg/d) or placebo for a week, and then participated in a laboratory experiment consisting of three procedures: alcohol cue-reactivity, priming, and self-administration. During the experiment, craving and other subjective responses to alcohol were assessed, and blood samples were collected for pharmacokinetic measurements. The effects of baclofen on the relationships between different alcohol-related laboratory parameters were investigated. Baclofen pharmacokinetic parameters and their correlations with behavioral measures were also examined. Results showed that baclofen disrupted the link between alcohol priming and self-administration, as indicated by significant interaction effects between drug condition (baclofen vs. placebo) and some of the priming variables (alcohol craving: F3,9 = 6.03, p = 0.01; alcohol sedation: F3,6 = 7.16, p = 0.01) on the total amount of alcohol self-administered. Considerable interindividual variability in baclofen pharmacokinetic parameters was observed. Maximum plasma concentrations of baclofen negatively correlated with cue-induced alcohol craving (r = -0.57, p = 0.03) and priming-induced ratings of 'like more' (r = -0.59, p = 0.02). In conclusion, baclofen may work by dissociating the link between an initial drink (priming) and subsequent alcohol consumption (self-administration). Considerable pharmacokinetic variability is an important factor to take into account when employing baclofen as a treatment for alcohol use disorder.


Asunto(s)
Alcoholismo , Agonistas de Receptores GABA-B , Alcoholismo/tratamiento farmacológico , Baclofeno , Humanos , Laboratorios , Receptores de GABA-B
17.
PLoS Biol ; 17(4): e2006421, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30990816

RESUMEN

Oxytocin administration has been reported to decrease consumption, withdrawal, and drug-seeking associated with several drugs of abuse and thus represents a promising pharmacological approach to treat drug addiction. We used an established rat model of alcohol dependence to investigate oxytocin's effects on dependence-induced alcohol drinking, enhanced motivation for alcohol, and altered GABAergic transmission in the central nucleus of the amygdala (CeA). Intraperitoneal oxytocin administration blocked escalated alcohol drinking and the enhanced motivation for alcohol in alcohol-dependent but not nondependent rats. Intranasal oxytocin delivery fully replicated these effects. Intraperitoneal administration had minor but significant effects of reducing locomotion and intake of non-alcoholic palatable solutions, whereas intranasal oxytocin administration did not. In dependent rats, intracerebroventricular administration of oxytocin or the oxytocin receptor agonist PF-06655075, which does not cross the blood-brain barrier (i.e., it would not diffuse to the periphery), but not systemic administration of PF-06655075 (i.e., it would not reach the brain), decreased alcohol drinking. Administration of a peripherally restricted oxytocin receptor antagonist did not reverse the effect of intranasal oxytocin on alcohol drinking. Ex vivo electrophysiological recordings from CeA neurons indicated that oxytocin decreases evoked GABA transmission in nondependent but not in dependent rats, whereas oxytocin decreased the amplitude of spontaneous GABAergic responses in both groups. Oxytocin blocked the facilitatory effects of acute alcohol on GABA release in the CeA of dependent but not nondependent rats. Together, these results provide converging evidence that oxytocin specifically and selectively blocks the enhanced motivation for alcohol drinking that develops in alcohol dependence likely via a central mechanism that may result from altered oxytocin effects on CeA GABA transmission in alcohol dependence. Neuroadaptations in endogenous oxytocin signaling may provide a mechanism to further our understanding of alcohol use disorder.


Asunto(s)
Alcoholismo/tratamiento farmacológico , Neuronas GABAérgicas/efectos de los fármacos , Oxitocina/farmacología , Amígdala del Cerebelo/efectos de los fármacos , Amígdala del Cerebelo/metabolismo , Animales , Etanol/metabolismo , Etanol/farmacología , Potenciales Postsinápticos Inhibidores/fisiología , Inyecciones Intraperitoneales , Masculino , Motivación/efectos de los fármacos , Neuronas/fisiología , Oxitocina/metabolismo , Técnicas de Placa-Clamp , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Transmisión Sináptica/fisiología
18.
Environ Res ; 212(Pt A): 113218, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35390299

RESUMEN

BACKGROUND: Although phthalate exposures have been associated with adverse effects on male reproductive health, few studies have explored longitudinal associations with male pubertal development. OBJECTIVES: We examined the association of prepubertal urinary concentrations of phthalate metabolites with age at pubertal onset in a prospective cohort of Russian boys. METHODS: At enrollment at ages 8-9 years, medical history, dietary, and demographic information was collected. At entry and annually, physical examinations and pubertal staging [Genitalia (G), Pubarche (P), and testicular volume (TV, in ml)] were conducted and spot urines were collected. Prepubertal urine samples (defined as either TV = 1, 2 and G = 1, 2 or TV = 3 and G = 1) were pooled for each boy and phthalate metabolite concentrations were quantified using isotope dilution LC-MS/MS at Moscow State University. We measured 15 metabolites including those from anti-androgenic parent phthalates (AAPs) such as di (2-ethylhexyl) (DEHP) and di-isononyl (DiNP) phthalates as well as monobenzyl (MBzP), mono-n-butyl (MnBP), and mono-isobutyl (MiBP) metabolites. We calculated the molar sums of DEHP (∑DEHP), DiNP (∑DiNP), and AAP (∑AAP) metabolites. Separate interval-censored models were used to assess associations of quartiles of prepubertal phthalate metabolites with each pubertal onset indicator, G2+, P2+ and TV > 3 mL, adjusted for covariates and urine specific gravity. RESULTS: 304 boys had 752 prepubertal urine samples (median 2, range: 1-6) for pooling. In adjusted models, higher urinary AAPs were consistently associated with later pubertal onset (P2) with mean shifts ranging from 8.4 to 14.2 months for the highest versus lowest quartiles. Significantly later onset for G2 and TV > 3 mL was observed for higher versus lower quartiles of MiBP, MBzP, ∑DEHP and ∑DiNP. CONCLUSIONS: On average, boys with higher concentrations of prepubertal urinary AAPs had later pubertal onset by six months to over a year. The impact of AAPs on timing of male puberty may be attributable to disruption of androgen-dependent biological pathways.


Asunto(s)
Dietilhexil Ftalato , Contaminantes Ambientales , Ácidos Ftálicos , Antagonistas de Andrógenos , Niño , Cromatografía Liquida , Exposición a Riesgos Ambientales/análisis , Contaminantes Ambientales/orina , Humanos , Masculino , Ácidos Ftálicos/orina , Estudios Prospectivos , Espectrometría de Masas en Tándem
19.
Addict Biol ; 27(1): e13033, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33908131

RESUMEN

Ghrelin is a gastric-derived peptide hormone with demonstrated impact on alcohol intake and craving, but the reverse side of this bidirectional link, that is, the effects of alcohol on the ghrelin system, remains to be fully established. To further characterize this relationship, we examined (1) ghrelin levels via secondary analysis of human laboratory alcohol administration experiments with heavy-drinking participants; (2) expression of ghrelin, ghrelin receptor, and ghrelin-O-acyltransferase (GOAT) genes (GHRL, GHSR, and MBOAT4, respectively) in post-mortem brain tissue from individuals with alcohol use disorder (AUD) versus controls; (3) ghrelin levels in Ghsr knockout and wild-type rats following intraperitoneal (i.p.) alcohol administration; (4) effect of alcohol on ghrelin secretion from gastric mucosa cells ex vivo and GOAT enzymatic activity in vitro; and (5) ghrelin levels in rats following i.p. alcohol administration versus a calorically equivalent non-alcoholic sucrose solution. Acyl- and total-ghrelin levels decreased following acute alcohol administration in humans, but AUD was not associated with changes in central expression of ghrelin system genes in post-mortem tissue. In rats, alcohol decreased acyl-ghrelin, but not des-acyl-ghrelin, in both Ghsr knockout and wild-type rats. No dose-dependent effects of alcohol were observed on acyl-ghrelin secretion from gastric mucosa cells or on GOAT acylation activity. Lastly, alcohol and sucrose produced distinct effects on ghrelin in rats despite equivalent caloric value. Our findings suggest that alcohol acutely decreases peripheral ghrelin concentrations in vivo, but not in proportion to alcohol's caloric value or through direct interaction with ghrelin-secreting gastric mucosal cells, the ghrelin receptor, or the GOAT enzyme.


Asunto(s)
Etanol/metabolismo , Ghrelina/metabolismo , Receptores de Ghrelina/metabolismo , Animales , Glucemia/metabolismo , Ghrelina/análogos & derivados , Humanos , Masculino , Ratas , Transducción de Señal
20.
Int J Neuropsychopharmacol ; 24(6): 464-476, 2021 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-33560411

RESUMEN

BACKGROUND: Accumulating evidence has established a role for the orexigenic hormone ghrelin in alcohol-seeking behaviors. Accordingly, the ghrelin system may represent a potential pharmacotherapeutic target for alcohol use disorder. Ghrelin modulates several neuroendocrine pathways, such as appetitive, metabolic, and stress-related hormones, which are particularly relevant in the context of alcohol use. The goal of the present study was to provide a comprehensive assessment of neuroendocrine response to exogenous ghrelin administration, combined with alcohol, in heavy-drinking individuals. METHODS: This was a randomized, crossover, double-blind, placebo-controlled human laboratory study, which included 2 experimental alcohol administration paradigms: i.v. alcohol self-administration and i.v. alcohol clamp. Each paradigm consisted of 2 counterbalanced sessions of i.v. ghrelin or placebo administration. Repeated blood samples were collected during each session, and peripheral concentrations of the following hormones were measured: leptin, glucagon-like peptide-1, pancreatic polypeptide, gastric inhibitory peptide, insulin, insulin-like growth factor-1, cortisol, prolactin, and aldosterone. RESULTS: Despite some statistical differences, findings were consistent across the 2 alcohol administration paradigms: i.v. ghrelin, compared to placebo, increased blood concentrations of glucagon-like peptide-1, pancreatic polypeptide, cortisol, and prolactin, both acutely and during the whole session. Lower levels of leptin and higher levels of aldosterone were also found during the ghrelin vs placebo session. CONCLUSION: These findings, gathered from a clinically relevant sample of heavy-drinking individuals with alcohol use disorder, provide a deeper insight into the complex interplay between ghrelin and appetitive, metabolic, and stress-related neuroendocrine pathways in the context of alcohol use.


Asunto(s)
Consumo de Bebidas Alcohólicas/metabolismo , Alcoholismo/sangre , Depresores del Sistema Nervioso Central/farmacología , Ansia/efectos de los fármacos , Etanol/farmacología , Ghrelina/farmacología , Sistemas Neurosecretores/efectos de los fármacos , Adulto , Depresores del Sistema Nervioso Central/administración & dosificación , Método Doble Ciego , Etanol/administración & dosificación , Femenino , Ghrelina/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Autoadministración
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