Significant Functional Differences Between Dopamine D4 Receptor Polymorphic Variants Upon Heteromerization with α1A Adrenoreceptors.

The functional role of the dopamine D4 receptor (D4R) and its main polymorphic variants has become more evident with the demonstration of heteromers of D4R that control the function of frontal cortico-striatal neurons. Those include heteromers with the α2A adrenoceptor (α2AR) and with the D2R, localized in their cortical somato-dendritic region and striatal nerve terminals, respectively. By using biophysical and cell-signaling methods and heteromer-disrupting peptides in mammalian transfected cells and rat brain slice preparations, here we provide evidence for a new functionally relevant D4R heteromer, the α1AR-D4R heteromer, which is also preferentially localized in cortico-striatal glutamatergic terminals. Significant differences in allosteric modulations between heteromers of α1AR with the D4.4R and D4.7R polymorphic variants could be evidenced with the analysis of G protein-dependent and independent signaling. Similar negative allosteric modulations between α1AR and D4R ligands could be demonstrated for both α1AR-D4.4R and α1AR-D4.7R heteromers on G protein-independent signaling, but only for α1AR-D4.4R on G protein-dependent signaling. From these functional differences, it is proposed that the D4.4R variant provides a gain of function of the α1AR-mediated noradrenergic stimulatory control of cortico-striatal glutamatergic neurotransmission, which could result in a decrease in the vulnerability for impulse control-related neuropsychiatric disorders and increase in the vulnerability for posttraumatic stress disorder.

Tenofovir Disoproxil Fumarate/Emtricitabine and Baricitinib for Patients at High Risk of Severe Coronavirus Disease 2019: The PANCOVID Randomized Clinical Trial.

BACKGROUND: This study was designed to evaluate if patients with high risk for severe coronavirus disease 2019 (COVID-19) would benefit from treatment with tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) followed by baricitinib in case of hypoxemia and systemic inflammation. METHODS: PANCOVID is an open-label, double-randomized, phase 3 pragmatic clinical trial including adults with symptomatic COVID-19 with ≥2 comorbidities or aged ≥60 years and was conducted between 10 October 2020 and 23 September 2021. In the first randomization, patients received TDF/FTC or no TDF/FTC. In the second randomization, patients with room air oxygen saturation <95% and at least 1 increased inflammatory biomarker received baricitinib plus dexamethasone or dexamethasone alone. The primary endpoint was 28-day mortality. Main secondary endpoint was 28-day disease progression or critical care unit admission or mortality. The trial was stopped before reaching planned sample size due to the decrease in the number of cases and a mortality rate substantially lower than expected. RESULTS: Of the 355 included participants, 97% were hospitalized at baseline. Overall, 28-day mortality was 3.1%. The 28-day mortality relative risk (RR) for participants treated with TDF/FTC was 1.76 (95% confidence interval [CI], .52-5.91; P = .379); it was 0.42 (95% CI, .11-1.59; P = .201) for those treated with baricitinib. The 28-day RR for the main secondary combined endpoint for participants treated with TDF/FTC was 0.95 (95% CI, .66-1.40; P = .774); it was 0.90 (95% CI, .61-1.33; P = .687) for those treated with baricitinib. CONCLUSIONS: Our results do not suggest a beneficial effect of TDF/FTC; nevertheless, they are compatible with the beneficial effect of baricitinib already established by other clinical trials. CLINICAL TRIALS REGISTRATION: EudraCT: 2020-001156-18.

Heteromerization between α2A adrenoceptors and different polymorphic variants of the dopamine D4 receptor determines pharmacological and functional differences. Implications for impulsive-control disorders.

Polymorphic alleles of the human dopamine D4 receptor gene (DRD4) have been consistently associated with individual differences in personality traits and neuropsychiatric disorders, particularly between the gene encoding dopamine D4.7 receptor variant and attention deficit hyperactivity disorder (ADHD). The α2A adrenoceptor gene has also been associated with ADHD. In fact, drugs targeting the α2A adrenoceptor (α2AR), such as guanfacine, are commonly used in ADHD treatment. In view of the involvement of dopamine D4 receptor (D4R) and α2AR in ADHD and impulsivity, their concurrent localization in cortical pyramidal neurons and the demonstrated ability of D4R to form functional heteromers with other G protein-coupled receptors, in this study we evaluate whether the α2AR forms functional heteromers with D4R and weather these heteromers show different properties depending on the D4R variant involved. Using cortical brain slices from hD4.7R knock-in and wild-type mice, here, we demonstrate that α2AR and D4R heteromerize and constitute a significant functional population of cortical α2AR and D4R. Moreover, in cortical slices from wild-type mice and in cells transfected with α2AR and D4.4R, we detect a negative crosstalk within the heteromer. This negative crosstalk is lost in cortex from hD4.7R knock-in mice and in cells expressing the D4.7R polymorphic variant. We also show a lack of efficacy of D4R ligands to promote G protein activation and signaling only within the α2AR-D4.7R heteromer. Taken together, our results suggest that α2AR-D4R heteromers play a pivotal role in catecholaminergic signaling in the brain cortex and are likely targets for ADHD pharmacotherapy.

Late presentation for HIV remains a major health issue in Spain: Results from a multicenter cohort study, 2004-2018.

OBJECTIVES: With the purpose of reducing the well-known negative impact of late presentation (LP) on people living with HIV (PLWH), guidelines on early HIV diagnosis were published in 2014 in Spain, but since then no data on LP prevalence have been published. To estimate prevalence and risk factors of LP and to evaluate their impact on the development of clinical outcomes in the Cohort of the Spanish HIV/AIDS Research Network (CoRIS) during 2004-2018. METHODS: CoRIS is an open prospective multicenter cohort of PLWH, adults, naive to ART at entry. LP was defined as HIV diagnosis with CD4 count ≤350 cells/µL or an AIDS defining event (ADE). Multivariable Poisson regression models were used to estimate both prevalence ratios (PR) for the association of potential risk factors with LP and Incidence rate ratios (IRRs) for its impact on the development of the composite endpoint (first ADE, first serious non-AIDS event [SNAE] or overall mortality). RESULTS: 14,876 individuals were included. Overall, LP prevalence in 2004-2018 was 44.6%. Risk factors for LP included older age, having been infected through injection drug use or heterosexual intercourse, low educational level and originating from non-European countries. LP was associated with an increased risk of the composite endpoint (IRR: 1.34; 95%CI 1.20, 1.50), ADE (1.39; 1.18, 1.64), SNAE (1.22; 1.01, 1.47) and mortality (1.71; 1.41, 2.08). CONCLUSIONS: LP remains a health problem in Spain, mainly among certain populations, and is associated with greater morbidity and mortality. Public policies should be implemented to expand screening and early diagnosis of HIV infection, for a focus on those at greatest risk of LP.

Efectividad de los glucocorticoides en pacientes hospitalizados por neumonía grave por SARS-CoV-2 / Effectiveness of glucocorticoids in patients hospitalized for severe SARS-CoV-2 pneumonia

Introducción: Se han comunicado varios trabajos donde se ha demostrado un efecto beneficioso de los glucocorticoides como tratamiento de la tormenta de citocinas que se asocia a los cuadros graves por SARS-CoV-2, plateándose diferentes pautas de glucocorticoides.MétodosEstudio observacional retrospectivo que incluye pacientes con neumonía grave por SARS-CoV-2 y compara el ingreso en una unidad de cuidados intensivos (UCI) o fallecimiento durante la hospitalización en 3 grupos de pacientes: sin tratamiento con glucocorticoides, uso de dosis diarias de glucocorticoides equivalentes menores a 250mg de prednisona y dosis diarias equivalentes mayores o iguales a 250mg de prednisona. Se realizó un análisis multivariante mediante regresión logística, utilizando el índice de propensión como covariante.ResultadosDe los 259 pacientes incorporados al estudio 67 (25,9%) tuvieron una evolución desfavorable, falleciendo o precisando ingreso en UCI. Los análisis comparativos entre diferentes tratamientos con glucocorticoides, y la asociación con ingreso en UCI o fallecimiento fueron: tratamiento con glucocorticoides (cualquier dosis) versus sin tratamiento con glucocorticoides (OR: 0,71 [0,30-1,66]), tratamiento con glucocorticoides (≥250mg de prednisona al día) versus sin tratamiento con glucocorticoides (OR: 0,35 [0,11-1,08]) y tratamiento con glucocorticoides (≥250mg de prednisona al día) versus pacientes con dosis de glucocorticoides<250mg de prednisona o sin tratamiento con glucocorticoides (OR: 0,30 [0,10-0,88]).ConclusiónLos resultados de este estudio muestran que los paciente con neumonía grave por SARS-CoV-2 tratados con pulsos con glucocorticoides con dosis equivalentes de prednisona mayor o igual de 250mg tienen una evolución más favorable (menos mortalidad e ingreso en UCI). (AU)

Introduction: Several studies have reported the beneficial effect of glucocorticoids in the treatment of cytokine storm that occurs in patients with severe COVID-19. Various glucocorticoids regimens have been proposed.MethodsRetrospective observational study that includes patients with severe SARS-CoV-2 pneumonia and compares admission to an Intensive Care Unit (ICU) or death during hospitalization in three groups of patients: no glucocorticoids treatment, use of glucocorticoids doses equivalent to less than 250mg of prednisone daily and use of equivalent doses greater than or equal to 250mg of prednisone daily. Multivariate analysis was performed using logistic regression, using the propensity index as a covariant.ResultsOf the 259 patients enrolled in the study, 67 (25.9%) had an unfavorable evolution, dying or requiring ICU admission. Comparative analyzes between different glucocorticoids treatments and the association with ICU admission or death were: glucocorticoids treatment (any dose) versus no glucocorticoids treatment (OR: 0.71 [0.30-1.66]), treatment with glucocorticoids (≥250mg prednisone daily) versus no glucocorticoids treatment (OR: 0.35 [0.11-1.08]) and glucocorticoids treatment (≥250mg prednisone daily) versus patients with glucocorticoids doses <250mg prednisone daily or without glucocorticoids treatment (OR: 0.30 [0.10-0.88]).ConclusionThe results of this study show that patients with severe SARS-CoV-2 pneumonia treated with glucocorticoids pulses with equivalent doses of prednisone greater than or equal to 250mg have a more favorable evolution (less mortality and less admission to ICU). (AU)

Effectiveness of glucocorticoids in patients hospitalized for severe SARS-CoV-2 pneumonia.

BACKGROUND: Several studies have reported the beneficial effect of glucocorticoids in the treatment of cytokine storm that occurs in patients with severe COVID-19. Various glucocorticoids regimens have been proposed. METHODS: Retrospective observational study that includes patients with severe SARS-CoV-2 pneumonia and compares admission to an Intensive Care Unit (ICU) or death during hospitalization in three groups of patients: no glucocorticoids treatment, use of glucocorticoids doses equivalent to less than 250 mg of prednisone daily and use of equivalent doses greater than or equal to 250 mg of prednisone daily. Multivariate analysis was performed using logistic regression, using the propensity index as a covariant. RESULTS: Of the 259 patients enrolled in the study, 67 (25.9%) had an unfavorable evolution, dying or requiring ICU admission. Comparative analyzes between different glucocorticoids treatments and the association with ICU admission or death were: glucocorticoids treatment (any dose) versus no glucocorticoids treatment (OR: 0.71 [0.30-1.66]), treatment with glucocorticoids (≥250 mg prednisone daily) versus no glucocorticoids treatment (OR: 0.35 [0.11-1.08]) and glucocorticoids treatment (≥250 mg prednisone daily) versus patients with glucocorticoids doses <250 mg prednisone daily or without glucocorticoids treatment (OR: 0.30 [0.10-0.88]). CONCLUSION: The results of this study show that patients with severe SARS-CoV-2 pneumonia treated with glucocorticoids pulses with equivalent doses of prednisone greater than or equal to 250 mg have a more favorable evolution (less mortality and less admission to ICU).

INTRODUCCIÓN: Se han comunicado varios trabajos donde se ha demostrado un efecto beneficioso de los glucocorticoides como tratamiento de la tormenta de citocinas que se asocia a los cuadros graves por SARS-CoV-2, plateándose diferentes pautas de glucocorticoides. MÉTODOS: Estudio observacional retrospectivo que incluye pacientes con neumonía grave por SARS-CoV-2 y compara el ingreso en una unidad de cuidados intensivos (UCI) o fallecimiento durante la hospitalización en 3 grupos de pacientes: sin tratamiento con glucocorticoides, uso de dosis diarias de glucocorticoides equivalentes menores a 250 mg de prednisona y dosis diarias equivalentes mayores o iguales a 250 mg de prednisona. Se realizó un análisis multivariante mediante regresión logística, utilizando el índice de propensión como covariante. RESULTADOS: De los 259 pacientes incorporados al estudio 67 (25,9%) tuvieron una evolución desfavorable, falleciendo o precisando ingreso en UCI. Los análisis comparativos entre diferentes tratamientos con glucocorticoides, y la asociación con ingreso en UCI o fallecimiento fueron: tratamiento con glucocorticoides (cualquier dosis) versus sin tratamiento con glucocorticoides (OR: 0,71 [0,30­1,66]), tratamiento con glucocorticoides (≥250 mg de prednisona al día) versus sin tratamiento con glucocorticoides (OR: 0,35 [0,11­1,08]) y tratamiento con glucocorticoides (≥250 mg de prednisona al día) versus pacientes con dosis de glucocorticoides < 250 mg de prednisona o sin tratamiento con glucocorticoides (OR: 0,30 [0,10­0,88]). CONCLUSIÓN: Los resultados de este estudio muestran que los paciente con neumonía grave por SARS-CoV-2 tratados con pulsos con glucocorticoides con dosis equivalentes de prednisona mayor o igual de 250 mg tienen una evolución más favorable (menos mortalidad e ingreso en UCI).

[Effectiveness of glucocorticoids in patients hospitalized for severe SARS-CoV-2 pneumonia]. / Efectividad de los glucocorticoides en pacientes hospitalizados por neumonía grave por SARS-CoV-2.

INTRODUCTION: Several studies have reported the beneficial effect of glucocorticoids in the treatment of cytokine storm that occurs in patients with severe COVID-19. Various glucocorticoids regimens have been proposed. METHODS: Retrospective observational study that includes patients with severe SARS-CoV-2 pneumonia and compares admission to an Intensive Care Unit (ICU) or death during hospitalization in three groups of patients: no glucocorticoids treatment, use of glucocorticoids doses equivalent to less than 250mg of prednisone daily and use of equivalent doses greater than or equal to 250mg of prednisone daily. Multivariate analysis was performed using logistic regression, using the propensity index as a covariant. RESULTS: Of the 259 patients enrolled in the study, 67 (25.9%) had an unfavorable evolution, dying or requiring ICU admission. Comparative analyzes between different glucocorticoids treatments and the association with ICU admission or death were: glucocorticoids treatment (any dose) versus no glucocorticoids treatment (OR: 0.71 [0.30-1.66]), treatment with glucocorticoids (≥250mg prednisone daily) versus no glucocorticoids treatment (OR: 0.35 [0.11-1.08]) and glucocorticoids treatment (≥250mg prednisone daily) versus patients with glucocorticoids doses <250mg prednisone daily or without glucocorticoids treatment (OR: 0.30 [0.10-0.88]). CONCLUSION: The results of this study show that patients with severe SARS-CoV-2 pneumonia treated with glucocorticoids pulses with equivalent doses of prednisone greater than or equal to 250mg have a more favorable evolution (less mortality and less admission to ICU).

Mantle flow and deep electrical anisotropy in a main gateway: MT study in Tierra del Fuego.

Asthenospheric mantle flow drives lithospheric plate motion and constitutes a relevant feature of Earth gateways. It most likely influences the spatial pattern of seismic velocity and deep electrical anisotropies. The Drake Passage is a main gateway in the global pattern of mantle flow. The separation of the South American and Antarctic plates since the Oligocene produced this oceanic and mantle gateway connecting the Pacific and Atlantic oceans. Here we analyze the deep crustal and upper mantle electrical anisotropy of its northern margin using long period magnetotelluric data from Tierra del Fuego (Argentina). The influence of the surrounding oceans was taken into account to constrain the mantle electrical conductivity features. 3D electrical models were calculated to fit 18 sites responses in this area. The phase tensor pattern for the longest periods reveals the existence of a well-defined NW-SE electrical conductivity anisotropy in the upper mantle. This anisotropy would result from the mantle flow related to the 30 to 6 Ma West Scotia spreading, constricted by the subducted slab orientation of the Pacific plate, rather than the later eastward mantle flow across the Drake Passage. Deep electrical anisotropy proves to be a key tool for a better understanding of mantle flow.

Therapeutic targeting of HER2-CB2R heteromers in HER2-positive breast cancer.

Although human epidermal growth factor receptor 2 (HER2)-targeted therapies have dramatically improved the clinical outcome of HER2-positive breast cancer patients, innate and acquired resistance remains an important clinical challenge. New therapeutic approaches and diagnostic tools for identification, stratification, and treatment of patients at higher risk of resistance and recurrence are therefore warranted. Here, we unveil a mechanism controlling the oncogenic activity of HER2: heteromerization with the cannabinoid receptor CB2R. We show that HER2 physically interacts with CB2R in breast cancer cells, and that the expression of these heteromers correlates with poor patient prognosis. The cannabinoid Δ9-tetrahydrocannabinol (THC) disrupts HER2-CB2R complexes by selectively binding to CB2R, which leads to (i) the inactivation of HER2 through disruption of HER2-HER2 homodimers, and (ii) the subsequent degradation of HER2 by the proteasome via the E3 ligase c-CBL. This in turn triggers antitumor responses in vitro and in vivo. Selective targeting of CB2R transmembrane region 5 mimicked THC effects. Together, these findings define HER2-CB2R heteromers as new potential targets for antitumor therapies and biomarkers with prognostic value in HER2-positive breast cancer.

Alpine bogs of southern Spain show human-induced environmental change superimposed on long-term natural variations.

Recent studies have proved that high elevation environments, especially remote wetlands, are exceptional ecological sensors of global change. For example, European glaciers have retreated during the 20th century while the Sierra Nevada National Park in southern Spain witnessed the first complete disappearance of modern glaciers in Europe. Given that the effects of climatic fluctuations on local ecosystems are complex in these sensitive alpine areas, it is crucial to identify their long-term natural trends, ecological thresholds, and responses to human impact. In this study, the geochemical records from two adjacent alpine bogs in the protected Sierra Nevada National Park reveal different sensitivities and long-term environmental responses, despite similar natural forcings, such as solar radiation and the North Atlantic Oscillation, during the late Holocene. After the Industrial Revolution both bogs registered an independent, abrupt and enhanced response to the anthropogenic forcing, at the same time that the last glaciers disappeared. The different response recorded at each site suggests that the National Park and land managers of similar regions need to consider landscape and environmental evolution in addition to changing climate to fully understand implications of climate and human influence.