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1.
bioRxiv ; 2024 Jul 08.
Article de Anglais | MEDLINE | ID: mdl-39026865

RÉSUMÉ

The capacity of the brain to compensate for insults during development depends on the type of cell loss, whereas the consequences of genetic mutations in the same neurons are difficult to predict. We reveal powerful compensation from outside the cerebellum when the excitatory cerebellar output neurons are ablated embryonically and demonstrate that the minimum requirement for these neurons is for motor coordination and not learning and social behaviors. In contrast, loss of the homeobox transcription factors Engrailed1/2 (EN1/2) in the cerebellar excitatory lineage leads to additional deficits in adult learning and spatial working memory, despite half of the excitatory output neurons being intact. Diffusion MRI indicates increased thalamo-cortico-striatal connectivity in En1/2 mutants, showing that the remaining excitatory neurons lacking En1/2 exert adverse effects on extracerebellar circuits regulating motor learning and select non-motor behaviors. Thus, an absence of cerebellar output neurons is less disruptive than having cerebellar genetic mutations.

2.
Neuropharmacology ; 257: 110031, 2024 Oct 01.
Article de Anglais | MEDLINE | ID: mdl-38871116

RÉSUMÉ

Exposure to chronic and unpredictable stressors can precipitate mood-related disorders in humans, particularly in individuals with pre-existing mental health challenges. L-type calcium channels (LTCCs) have been implicated in numerous neuropsychiatric disorders, as LTCC encoding genes have been identified as candidate risk factors for neuropsychiatric illnesses. In these sets of experiments, we sought to examine the ability of LTCC blockade to alter depression, anxiety, and anhedonic-related behavioral responses to chronic unpredictable stress (CUS) exposure in female and male rats. Rats first underwent either 21 days of CUS or no exposure to chronic stressors, serving as home cage controls (HCC). Then rats were examined for anhedonia-related behavior, anxiety and depression-like behavioral responses as measured by the sucrose preference test (SPT), elevated plus maze (EPM), and forced swim test (FST). CUS exposed females and males showed anhedonic and anxiogenic-like behavioral responses on the SPT and EPM, respectively, when compared to HCCs. In female and male rats, systemic administration of the LTCC blocker isradipine (0.4 mg/kg and 1.2 mg/kg, I.P.) attenuated the CUS-induced decrease in sucrose preference and reversed the CUS-induced decrease in open arm time. In the FST, systemic isradipine decreased immobility time across all groups, consistent with an antidepressant-like response. However, there were no significant differences in forced swim test immobility time between HCC and CUS exposed animals. Taken together, these data point to a role of LTCCs in the regulation of mood disorder-related behavioral phenotype responses to chronic stress exposure.


Sujet(s)
Anhédonie , Anxiété , Inhibiteurs des canaux calciques , Canaux calciques de type L , Dépression , Stress psychologique , Animaux , Anhédonie/physiologie , Anhédonie/effets des médicaments et des substances chimiques , Mâle , Stress psychologique/métabolisme , Stress psychologique/psychologie , Femelle , Canaux calciques de type L/métabolisme , Dépression/métabolisme , Anxiété/métabolisme , Rats , Inhibiteurs des canaux calciques/pharmacologie , Rat Sprague-Dawley , Modèles animaux de maladie humaine , Phénotype , Préférences alimentaires/effets des médicaments et des substances chimiques , Préférences alimentaires/physiologie
3.
bioRxiv ; 2024 Apr 02.
Article de Anglais | MEDLINE | ID: mdl-38766079

RÉSUMÉ

Converging findings have established that the endocannabinoid (eCB) system serves as a possible target for the development of new treatments for pain as a complement to opioid-based treatments. Here we show in male and female mice that enhancing levels of the eCB, 2-arachidonoylglycerol (2-AG), through pharmacological inhibition of its catabolic enzyme, monoacylglycerol lipase (MAGL), either systemically or in the ventral tegmental area (VTA) with JZL184, leads to a substantial attenuation of the rewarding effects of opioids in male and female mice using conditioned place preference and self-administration paradigms, without altering their analgesic properties. These effects are driven by CB1 receptors (CB1Rs) within the VTA as VTA CB1R conditional knockout, counteracts JZL184's effects. Conversely, pharmacologically enhancing the levels of the other eCB, anandamide (AEA), by inhibition of fatty acid amide hydrolase (FAAH) has no effect on opioid reward or analgesia. Using fiber photometry with fluorescent sensors for calcium and dopamine (DA), we find that enhancing 2-AG levels diminishes opioid reward-related nucleus accumbens (NAc) activity and DA neurotransmission. Together these findings reveal that 2-AG counteracts the rewarding properties of opioids and provides a potential adjunctive therapeutic strategy for opioid-related analgesic treatments.

4.
Lancet ; 403(10442): 2405-2415, 2024 Jun 01.
Article de Anglais | MEDLINE | ID: mdl-38763154

RÉSUMÉ

BACKGROUND: Previous evidence indicates that adjuvant, short-course androgen deprivation therapy (ADT) improves metastasis-free survival when given with primary radiotherapy for intermediate-risk and high-risk localised prostate cancer. However, the value of ADT with postoperative radiotherapy after radical prostatectomy is unclear. METHODS: RADICALS-HD was an international randomised controlled trial to test the efficacy of ADT used in combination with postoperative radiotherapy for prostate cancer. Key eligibility criteria were indication for radiotherapy after radical prostatectomy for prostate cancer, prostate-specific antigen less than 5 ng/mL, absence of metastatic disease, and written consent. Participants were randomly assigned (1:1) to radiotherapy alone (no ADT) or radiotherapy with 6 months of ADT (short-course ADT), using monthly subcutaneous gonadotropin-releasing hormone analogue injections, daily oral bicalutamide monotherapy 150 mg, or monthly subcutaneous degarelix. Randomisation was done centrally through minimisation with a random element, stratified by Gleason score, positive margins, radiotherapy timing, planned radiotherapy schedule, and planned type of ADT, in a computerised system. The allocated treatment was not masked. The primary outcome measure was metastasis-free survival, defined as distant metastasis arising from prostate cancer or death from any cause. Standard survival analysis methods were used, accounting for randomisation stratification factors. The trial had 80% power with two-sided α of 5% to detect an absolute increase in 10-year metastasis-free survival from 80% to 86% (hazard ratio [HR] 0·67). Analyses followed the intention-to-treat principle. The trial is registered with the ISRCTN registry, ISRCTN40814031, and ClinicalTrials.gov, NCT00541047. FINDINGS: Between Nov 22, 2007, and June 29, 2015, 1480 patients (median age 66 years [IQR 61-69]) were randomly assigned to receive no ADT (n=737) or short-course ADT (n=743) in addition to postoperative radiotherapy at 121 centres in Canada, Denmark, Ireland, and the UK. With a median follow-up of 9·0 years (IQR 7·1-10·1), metastasis-free survival events were reported for 268 participants (142 in the no ADT group and 126 in the short-course ADT group; HR 0·886 [95% CI 0·688-1·140], p=0·35). 10-year metastasis-free survival was 79·2% (95% CI 75·4-82·5) in the no ADT group and 80·4% (76·6-83·6) in the short-course ADT group. Toxicity of grade 3 or higher was reported for 121 (17%) of 737 participants in the no ADT group and 100 (14%) of 743 in the short-course ADT group (p=0·15), with no treatment-related deaths. INTERPRETATION: Metastatic disease is uncommon following postoperative bed radiotherapy after radical prostatectomy. Adding 6 months of ADT to this radiotherapy did not improve metastasis-free survival compared with no ADT. These findings do not support the use of short-course ADT with postoperative radiotherapy in this patient population. FUNDING: Cancer Research UK, UK Research and Innovation (formerly Medical Research Council), and Canadian Cancer Society.


Sujet(s)
Antagonistes des androgènes , Anilides , Nitriles , Prostatectomie , Tumeurs de la prostate , Composés tosyliques , Humains , Mâle , Tumeurs de la prostate/anatomopathologie , Tumeurs de la prostate/radiothérapie , Tumeurs de la prostate/thérapie , Tumeurs de la prostate/traitement médicamenteux , Antagonistes des androgènes/usage thérapeutique , Antagonistes des androgènes/administration et posologie , Sujet âgé , Composés tosyliques/usage thérapeutique , Composés tosyliques/administration et posologie , Anilides/usage thérapeutique , Anilides/administration et posologie , Adulte d'âge moyen , Nitriles/usage thérapeutique , Nitriles/administration et posologie , Oligopeptides/usage thérapeutique , Oligopeptides/administration et posologie , Hormone de libération des gonadotrophines/agonistes , Association thérapeutique , Antigène spécifique de la prostate/sang
5.
bioRxiv ; 2024 Apr 18.
Article de Anglais | MEDLINE | ID: mdl-38659789

RÉSUMÉ

Developmental and Epileptic Encephalopathies (DEEs), a class of devastating neurological disorders characterized by recurrent seizures and exacerbated by disruptions to excitatory/inhibitory balance in the brain, are commonly caused by mutations in ion channels. Disruption of, or variants in, FGF13 were implicated as causal for a set of DEEs, but the underlying mechanisms were clouded because FGF13 is expressed in both excitatory and inhibitory neurons, FGF13 undergoes extensive alternative splicing producing multiple isoforms with distinct functions, and the overall roles of FGF13 in neurons are incompletely cataloged. To overcome these challenges, we generated a set of novel cell type-specific conditional knockout mice. Interneuron-targeted deletion of Fgf13 led to perinatal mortality associated with extensive seizures and impaired the hippocampal inhibitory/excitatory balance while excitatory neuron-targeted deletion of Fgf13 caused no detectable seizures and no survival deficits. While best studied as a voltage-gated sodium channel (Nav) regulator, we observed no effect of Fgf13 ablation in interneurons on Navs but rather a marked reduction in K+ channel currents. Re-expressing different Fgf13 splice isoforms could partially rescue deficits in interneuron excitability and restore K+ channel current amplitude. These results enhance our understanding of the molecular mechanisms that drive the pathogenesis of Fgf13-related seizures and expand our understanding of FGF13 functions in different neuron subsets.

6.
iScience ; 27(1): 108724, 2024 Jan 19.
Article de Anglais | MEDLINE | ID: mdl-38226163

RÉSUMÉ

Circulating cell-free mitochondrial DNA (ccf-mtDNA) acts as a damage-associated molecular pattern molecule and may be cargo within extracellular vesicles (EVs). ccf-mtDNA and select mitochondrial DNA (mtDNA) haplogroups are associated with cardiovascular disease. We hypothesized that ccf-mtDNA and plasma EV mtDNA would be associated with hypertension, sex, self-identified race, and mtDNA haplogroup ancestry. Participants were normotensive (n = 107) and hypertensive (n = 108) African American and White adults from the Healthy Aging in Neighborhoods of Diversity across the Life Span study. ccf-mtDNA levels were higher in African American participants compared with White participants in both plasma and EVs, but ccf-mtDNA levels were not related to hypertension. EV mtDNA levels were highest in African American participants with African mtDNA haplogroup. Circulating inflammatory protein levels were altered with mtDNA haplogroup, race, and EV mtDNA. Our findings highlight that race is a social construct and that ancestry is crucial when examining health and biomarker differences between groups.

7.
Dis Colon Rectum ; 67(3): 406-413, 2024 Mar 01.
Article de Anglais | MEDLINE | ID: mdl-38039388

RÉSUMÉ

BACKGROUND: Postoperative recurrence remains a significant problem in Crohn's disease, and the mesentery is implicated in the pathophysiology. The Kono-S anastomosis was designed to exclude the mesentery from a wide anastomotic lumen, limit luminal distortion and fecal stasis, and preserve innervation and vascularization. OBJECTIVE: To review postoperative complications and long-term outcomes of the Kono-S anastomosis in a large series of consecutive unselected patients with Crohn's disease. DESIGN: Retrospective study of prospectively collected patients. SETTINGS: Four tertiary referral centers. PATIENTS: Consecutive patients with Crohn's disease who underwent resection with Kono-S anastomosis between May 2010 and June 2022. INTERVENTIONS: Extracorporeal handsewn Kono-S anastomosis. MAIN OUTCOME MEASURES: Postoperative outcomes and recurrence defined as endoscopic, clinical, laboratory, or surgical, including endoscopic, intervention. RESULTS: A total of 262 consecutive patients (53.4% male) were included. The mean duration of disease at surgery was 145.1 months. One hundred thirty-five patients (51.5%) had previous abdominal surgery for Crohn's disease. Forty-four patients (17%) were actively smoking and 150 (57.3%) were on biologic therapy. Anastomotic failure occurred in 4 (1.5%), with 2 patients requiring reoperation (0.7%). Sixteen patients had postoperative surgical site infection (6.1%). With a median follow-up of 49.4 months, 20 patients (7.6%) were found to have surgical recurrence. In the multivariate analysis, perianal disease (OR = 2.83, p = 0.001), urgent/emergent surgery (OR = 3.23, p = 0.007), and postoperative use of steroids (OR = 2.29, p = 0.025) were associated with increased risk of overall recurrence. LIMITATIONS: Retrospective study and variability of perioperative medical therapy. CONCLUSIONS: This study showed very low postoperative complication rates despite the complexity of the patient population. There was a low rate of surgical recurrence, likely due to the intrinsic advantages of the anastomotic configuration and the low rate of postoperative septic complications. In experienced hands, the Kono-S anastomosis is a safe technique with very promising short- and long-term results. Randomized controlled trials are underway to validate this study's findings. See Video Abstract . RESULTADO A LARGO PLAZO DE LA ANASTOMOSIS KONOS UN ESTUDIO MULTICNTRICO: ANTECEDENTES:La recurrencia posoperatoria sigue siendo un problema importante en la enfermedad de Crohn y el mesenterio está implicado en la fisiopatología. La anastomosis Kono-S fue diseñada para excluir el mesenterio de una anastomosis amplia, limitar la distorsión luminal y la estasis fecal y preservar la inervación y vascularización.OBJETIVO:Revisar las complicaciones posoperatorias y los resultados a largo plazo de la anastomosis Kono-S en una gran serie de pacientes consecutivos no seleccionados con enfermedad de Crohn.DISEÑO:Estudio retrospectivo de pacientes recolectados prospectivamente.ESCENARIO:Cuatro centros de referencia terciarios.PACIENTES:Pacientes consecutivos con enfermedad de Crohn sometidos a resección con anastomosis Kono-S entre mayo de 2010 y junio de 2022.INTERVENCIONES:Anastomosis Kono-S extracorpórea manual.PRINCIPALES MEDIDAS DE RESULTADO:Resultados posoperatorios y recurrencia definidos como endoscópicos, clínicos, de laboratorio o quirúrgicos, incluida la intervención endoscópica.RESULTADOS:Se incluyeron un total de 262 pacientes consecutivos (53,4% varones). La duración media de la enfermedad al momento de la cirugía fue de 145,1 meses. Ciento treinta y cinco pacientes (51,5%) habían tenido cirugía abdominal previa por enfermedad de Crohn. Cuarenta y cuatro pacientes (17%) eran fumadores activos y 150 (57,3%) estaban en tratamiento biológico. Se produjo filtración anastomótica en 4 (1,5%) y 2 pacientes requirieron reoperación (0,7%). Dieciséis pacientes tuvieron infección postoperatoria del sitio quirúrgico (6,1%). Con una mediana de seguimiento de 49,4 meses, se encontró que 20 pacientes (7,6%) tuvieron recurrencia quirúrgica. En el análisis multivariado, la enfermedad perianal (OR = 2,83, p = 0,001), la cirugía urgente/emergente (OR = 3,23, p = 0,007), el uso postoperatorio de esteroides (OR = 2,29, p = 0,025) se asociaron con un mayor riesgo de recurrencia general.LIMITACIÓN:Estudio retrospectivo. Variabilidad del tratamiento médico perioperatorio.CONCLUSIONES:Nuestro estudio mostró tasas de complicaciones postoperatorias muy bajas a pesar de la complejidad de la población de pacientes. Hubo una baja tasa de recurrencia quirúrgica, probablemente debido a las ventajas intrínsecas de la configuración anastomótica y la baja tasa de complicaciones sépticas posoperatorias. En manos experimentadas, la anastomosis Kono-S es una técnica segura con resultados muy prometedores a corto y largo plazo. Se están realizando estudios randomizados controlados para validar nuestros hallazgos. (Traducción-Dr. Felipe Bellolio ).


Sujet(s)
Maladie de Crohn , Humains , Mâle , Femelle , Études rétrospectives , Maladie de Crohn/chirurgie , Anastomose chirurgicale/méthodes , Infection de plaie opératoire , Complications postopératoires/épidémiologie , Essais contrôlés randomisés comme sujet
8.
Indian J Community Med ; 48(5): 702-708, 2023.
Article de Anglais | MEDLINE | ID: mdl-37970160

RÉSUMÉ

Introduction: The interrelationship of diabetes with mental illness has increased in recent years. Diabetes-related distress is the emotional burden, stress, and worries associated with diabetes, which does not reach the threshold for depressive disorder. A diabetes self-management education (DSME) is a structured educational approach to improve glycemic control and diabetes-related distress. This study aimed to assess the effectiveness of DSME in comparison with usual diabetes care in improving glycemic control and diabetes-related distress. Material and Methods: This is a single-center, parallel randomized controlled trial. A total of 106 participants were recruited for both intervention and control groups with 53 participants each. The control group received only routine outpatient department (OPD) care. The intervention group received DSME in addition to routine OPD care. Diabetes-related distress and HbA1C were assessed after 3 months. The data were analyzed using IBM Statistical Package for the Social Sciences (SPSS) version 25. Per-protocol analysis was done. Results: Of 127 patients screened, 106 met the eligibility criteria and were randomized. At 3-month follow-up, the reduction in mean HbA1C, fasting blood sugar (FBS), postprandial blood sugar (PPBS), and diabetes distress were significant in the intervention group compared with the control group (p 0.001). The mean HbA1C reduction in the intervention group was significant (mean difference: -1.3, SD: 0.4). The mean DDS had decreased significantly in the intervention group from 2 to 1.2 (mean difference: -0.8, SD: 0.1). Conclusion: The DSME was effective in improving the glycemic control, diabetes-related distress, and self-care among type 2 diabetes (T2DM) mellitus patients.

9.
bioRxiv ; 2023 Sep 23.
Article de Anglais | MEDLINE | ID: mdl-37790372

RÉSUMÉ

L-type Ca 2+ channels (Ca V 1.2/1.3) convey influx of calcium ions (Ca 2+ ) that orchestrate a bevy of biological responses including muscle contraction and gene transcription. Deficits in Ca V 1 function play a vital role in cardiac and neurodevelopmental disorders. Yet conventional pharmacological approaches to upregulate Ca V 1 are limited, as excessive Ca 2+ influx leads to cytotoxicity. Here, we develop a genetically encoded enhancer of Ca V 1.2/1.3 channels (GeeC) to manipulate Ca 2+ entry in distinct physiological settings. Specifically, we functionalized a nanobody that targets the Ca V macromolecular complex by attaching a minimal effector domain from a Ca V enhancer-leucine rich repeat containing protein 10 (Lrrc10). In cardiomyocytes, GeeC evoked a 3-fold increase in L-type current amplitude. In neurons, GeeC augmented excitation-transcription (E-T) coupling. In all, GeeC represents a powerful strategy to boost Ca V 1.2/1.3 function in distinct physiological settings and, in so doing, lays the groundwork to illuminate new insights on neuronal and cardiac physiology and disease.

10.
Article de Anglais | MEDLINE | ID: mdl-37867245

RÉSUMÉ

INTRODUCTION: Reverse total shoulder arthroplasty (RSA) is used to treat a variety of shoulder-related pathologies. This study compared medium-term clinical outcomes of less than 10-year follow-up in patients treated with RSA for proximal humerus fracture (PHF) versus rotator cuff arthropathy (RCA). METHODS: This retrospective review was conducted at two tertiary care centers, in which self-reported clinical outcomes were assessed using four validated instruments, that is, American Shoulder and Elbow Society (ASES) score, Shoulder Pain and Disability Index (SPADI), visual analog scale (VAS), and shoulder subjective value (SSV). Statistical analyses were performed using linear or logistic regression with generalized estimating equations. RESULTS: Of the 189 patients included in this study, 70 were treated for fracture and 119 for RCA. At a mean postoperative follow-up of 6.4 years, the means were 79.7 for ASES score, 20.8 for SPADI-Total, 0.8 for VAS, and 77.1 for SSV. After adjusting models for covariates, there was no significant difference in average SSV (P = 0.7), VAS (P = 0.7) or SPADI-Pain (P = 0.2) between PHF and RCA cohorts; however, the RCA cohort reported significantly better outcomes in ASES scores (P = 0.002), SPADI-Disability (P < 0.0001), and SPADI-Total (P = 0.0001). DISCUSSION: Patients with RCA and PHF treated with RSA achieved similar medium-term outcomes in several domains, particularly postoperative pain levels; however, patients with PHF reported greater perceived disability. RSA is an effective pain-controlling procedure, but patients may have variable functional outcomes based on the indication for surgery.


Sujet(s)
Arthroplastie de l'épaule , Fractures de l'humérus , Fractures de l'épaule , Humains , États-Unis , Arthroplastie de l'épaule/méthodes , Coiffe des rotateurs/chirurgie , Résultat thérapeutique , Scapulalgie/chirurgie , Fractures de l'épaule/chirurgie , Fractures de l'humérus/chirurgie
11.
bioRxiv ; 2023 Jun 26.
Article de Anglais | MEDLINE | ID: mdl-37425963

RÉSUMÉ

Impairments in social behavior are observed in a range of neuropsychiatric disorders and several lines of evidence have demonstrated that dysfunction of the prefrontal cortex (PFC) plays a central role in social deficits. We have previously shown that loss of neuropsychiatric risk gene Cacna1c that codes for the Cav1.2 isoform of L-type calcium channels (LTCCs) in the PFC result in impaired sociability as tested using the three-chamber social approach test. In this study we aimed to further characterize the nature of the social deficit associated with a reduction in PFC Cav1.2 channels (Cav1.2PFCKO mice) by testing male mice in a range of social and nonsocial tests while examining PFC neural activity using in vivo GCaMP6s fiber photometry. We found that during the first investigation of the social and non-social stimulus in the three-chamber test, both Cav1.2PFCKO male mice and Cav1.2PFCGFP controls spent significantly more time with the social stimulus compared to a non-social object. In contrast, during repeat investigations while Cav1.2PFCWT mice continued to spend more time with the social stimulus, Cav1.2PFCKO mice spent equal amount of time with both social and non-social stimuli. Neural activity recordings paralleled social behavior with increase in PFC population activity in Cav1.2PFCWT mice during first and repeat investigations, which was predictive of social preference behavior. In Cav1.2PFCKO mice, there was an increase in PFC activity during first social investigation but not during repeat investigations. These behavioral and neural differences were not observed during a reciprocal social interaction test nor during a forced alternation novelty test. To evaluate a potential deficit in reward-related processes, we tested mice in a three-chamber test wherein the social stimulus was replaced by food. Behavioral testing revealed that both Cav1.2PFCWT and Cav1.2PFCKO mice showed a preference for food over object with significantly greater preference during repeat investigation. Interestingly, there was no increase in PFC activity when Cav1.2PFCWT or Cav1.2PFCKO first investigated the food however activity significantly increased in Cav1.2PFCWT mice during repeat investigations of the food. This was not observed in Cav1.2PFCKO mice. In summary, a reduction in Cav1.2 channels in the PFC suppresses the development of a sustained social preference in mice that is associated with lack of PFC neuronal population activity that may be related to deficits in social reward.

12.
Proc Biol Sci ; 290(1996): 20222524, 2023 04 12.
Article de Anglais | MEDLINE | ID: mdl-37015271

RÉSUMÉ

Studies of the fossil record can inform our understanding of not only the causes of mass extinctions, but also their effects on biodiversity, ecology and evolution. Here, we examine regional-scale ecological changes resulting from a Late Devonian mass extinction event using brachiopod fossil assemblages from the Appalachian Basin. About half of the species went extinct, but were largely replaced by new immigrant taxa. Both before and after the extinction, the primary gradient in faunal composition was correlated with onshore-offshore position, with a second gradient attributed to frequency of disturbance. Survivors of the extinction displayed a strong degree of niche conservatism along these gradients. Despite these indicators of ecological stability, the pre- and post-extinction faunas were quite distinct at the order level, with atrypids and strophomenids largely replaced by productids, whose spiny shells may have provided greater resistance to disturbance and/or predation. Thus, extinction survivors persisted in similar ecological niches despite environmental perturbations and considerable change in the taxonomic and ecological composition of the regional species pool.


Sujet(s)
Extinction biologique , Invertébrés , Animaux , Écosystème , Fossiles , Biodiversité , Évolution biologique
13.
Nat Commun ; 14(1): 2487, 2023 04 29.
Article de Anglais | MEDLINE | ID: mdl-37120443

RÉSUMÉ

Social hierarchies exert a powerful influence on behavior, but the neurobiological mechanisms that detect and regulate hierarchical interactions are not well understood, especially at the level of neural circuits. Here, we use fiber photometry and chemogenetic tools to record and manipulate the activity of nucleus accumbens-projecting cells in the ventromedial prefrontal cortex (vmPFC-NAcSh) during tube test social competitions. We show that vmPFC-NAcSh projections signal learned hierarchical relationships, and are selectively recruited by subordinate mice when they initiate effortful social dominance behavior during encounters with a dominant competitor from an established hierarchy. After repeated bouts of social defeat stress, this circuit is preferentially activated during social interactions initiated by stress resilient individuals, and plays a necessary role in supporting social approach behavior in subordinated mice. These results define a necessary role for vmPFC-NAcSh cells in the adaptive regulation of social interaction behavior based on prior hierarchical interactions.


Sujet(s)
Comportement social , Interaction sociale , Souris , Animaux , Cortex préfrontal/physiologie , Dominance sociale , Noyau accumbens
14.
Channels (Austin) ; 17(1): 2176984, 2023 12.
Article de Anglais | MEDLINE | ID: mdl-36803254

RÉSUMÉ

Recent human genetic studies have linked a variety of genetic variants in the CACNA1C and CACNA1D genes to neuropsychiatric and neurodevelopmental disorders. This is not surprising given the work from multiple laboratories using cell and animal models that have established that Cav1.2 and Cav1.3 L-type calcium channels (LTCCs), encoded by CACNA1C and CACNA1D, respectively, play a key role in various neuronal processes that are essential for normal brain development, connectivity, and experience-dependent plasticity. Of the multiple genetic aberrations reported, genome-wide association studies (GWASs) have identified multiple single nucleotide polymorphisms (SNPs) in CACNA1C and CACNA1D that are present within introns, in accordance with the growing body of literature establishing that large numbers of SNPs associated with complex diseases, including neuropsychiatric disorders, are present within non-coding regions. How these intronic SNPs affect gene expression has remained a question. Here, we review recent studies that are beginning to shed light on how neuropsychiatric-linked non-coding genetic variants can impact gene expression via regulation at the genomic and chromatin levels. We additionally review recent studies that are uncovering how altered calcium signaling through LTCCs impact some of the neuronal developmental processes, such as neurogenesis, neuron migration, and neuron differentiation. Together, the described changes in genomic regulation and disruptions in neurodevelopment provide possible mechanisms by which genetic variants of LTCC genes contribute to neuropsychiatric and neurodevelopmental disorders.


Sujet(s)
Canaux calciques de type L , Étude d'association pangénomique , Animaux , Humains , Canaux calciques de type L/génétique , Canaux calciques de type L/métabolisme , Neurones/métabolisme , Encéphale/métabolisme , Génomique
15.
Immun Ageing ; 20(1): 6, 2023 Jan 30.
Article de Anglais | MEDLINE | ID: mdl-36710345

RÉSUMÉ

BACKGROUND: Frailty, a clinical syndrome commencing at midlife, is a risk for morbidity and mortality. Little is known about the factors that contribute to the chronic inflammatory state associated with frailty. Extracellular vesicles (EVs) are small, membrane-bound vesicles that are released into the circulation and are mediators of intercellular communication. We examined whether mitochondrial DNA (mtDNA) and inflammatory proteins in EVs may act as damage-associated molecular pattern (DAMP) molecules in frailty. RESULTS: To address whether EVs and their associated mtDNA and inflammatory protein cargo are altered with frailty, EVs were isolated from non-frail (n = 90) and frail (n = 87) middle-aged (45-55 years) participants from the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study. EV concentration was highest in frail White participants. EV mtDNA levels were significantly higher in frail individuals compared to non-frail individuals. The presence of six inflammatory proteins in EVs (FGF-21, HGF, IL-12B, PD-L1, PRDX3, and STAMBP) were significantly associated with frailty. EV inflammatory proteins were significantly altered by frailty status, race, sex, and poverty status. Notably, frail White participants had higher levels of EV-associated CD5, CD8A, CD244, CXCL1, CXCL6, CXCL11, LAP-TGF-beta-1 and MCP-4 compared to frail and non-frail African American participants. Frail White participants living below poverty had higher levels of EV-associated uPA. EV-associated CCL28 levels were highest in non-frail women and CXCL1 were highest in non-frail men. Men living below poverty had higher levels of CD5, CD8A, CXCL1, LAP-TGF-beta-1, and uPA. CXCL6 levels were significantly higher in individuals living above poverty. There was a significant correlation between EV mtDNA levels and the presence of inflammatory proteins. CONCLUSIONS: These data suggest that mtDNA within EVs may act as a DAMP molecule in frailty. Its association with chemokines and other inflammatory EV cargo proteins, may contribute to the frailty phenotype. In addition, the social determinant of health, poverty, influences the inflammatory cargo of EVs in midlife.

16.
Neuropharmacology ; 224: 109368, 2023 02 15.
Article de Anglais | MEDLINE | ID: mdl-36481277

RÉSUMÉ

We have previously demonstrated that pharmacological blockade of ventral tegmental area (VTA) Cav1.3 L-type calcium channels (LTCCs) using Cav1.2 dihydropyridine insensitive (Cav1.2DHP-/-) mutant mice attenuates cocaine conditioned place preference (CPP). However, the molecular mechanisms by which Cav1.3 channels mediate the effects of cocaine in the VTA remain largely unknown. In this study using Cav1.2DHP-/- male mice, we find that cocaine place preference increases CaM kinase IIα, ERK2, and CREB phosphorylation in the VTA, proteins strongly linked to cocaine behaviors. To further explore the causal role of these intracellular signaling proteins in cocaine preference, the CaM kinase II inhibitor, KN93 was directly injected into the VTA of male mice before each cocaine conditioning session. We found that KN93 attenuates conditioned preference for cocaine compared to vehicle treated mice and decreased VTA ERK2 and CREB phosphorylation. Additionally, blockade of the ERK pathway with the MEK inhibitor, U0126 or knockdown of ERK2 using siRNA, attenuated cocaine preference and VTA CREB phosphorylation but not CaMKIIα phosphorylation, suggesting that ERK is activated downstream of CaMKIIα. Examination of postsynaptic density (PSD) GluA1 subunit of AMPA receptors in the nucleus accumbens (NAc) that we have previously shown to be upregulated following long withdrawal periods, was blunted by KN93, U0126 and ERK2 siRNA when examined 30 days following cocaine CPP. Taken together, these findings demonstrate that Cav1.3 channels in the VTA are required for cocaine reward behavior and activation of the CaMKIIα/ERK/CREB signaling pathway in the VTA is necessary for long-lasting changes in the NAc. This article is part of the Special Issue on 'L-type calcium channel mechanisms in neuropsychiatric disorders'.


Sujet(s)
Cocaïne , Animaux , Mâle , Souris , Calcium-Calmodulin-Dependent Protein Kinase Type 2/métabolisme , Cocaïne/pharmacologie , Système de signalisation des MAP kinases , Noyau accumbens , Phosphorylation , Petit ARN interférent/pharmacologie , Aire tegmentale ventrale , Canaux calciques de type L/métabolisme
17.
Biol Sex Differ ; 13(1): 66, 2022 11 08.
Article de Anglais | MEDLINE | ID: mdl-36348414

RÉSUMÉ

BACKGROUND: Dysregulation in the prefrontal cortex underlies a variety of psychiatric illnesses, including substance use disorder, depression, and anxiety. Despite the established sex differences in prevalence and presentation of these illnesses, the neural mechanisms driving these differences are largely unexplored. Here, we investigate potential sex differences in glutamatergic transmission within the medial prefrontal cortex (mPFC). The goal of these experiments was to determine if there are baseline sex differences in transmission within this region that may underlie sex differences in diseases that involve dysregulation in the prefrontal cortex. METHODS: Adult male and female C57Bl/6J mice were used for all experiments. Mice were killed and bilateral tissue samples were taken from the medial prefrontal cortex for western blotting. Both synaptosomal and total GluA1 and GluA2 levels were measured. In a second set of experiments, mice were killed and ex vivo slice electrophysiology was performed on prepared tissue from the medial prefrontal cortex. Spontaneous excitatory postsynaptic currents and rectification indices were measured. RESULTS: Females exhibit higher levels of synaptosomal GluA1 and GluA2 in the mPFC compared to males. Despite similar trends, no statistically significant differences are seen in total levels of GluA1 and GluA2. Females also exhibit both a higher amplitude and higher frequency of spontaneous excitatory postsynaptic currents and greater inward rectification in the mPFC compared to males. CONCLUSIONS: Overall, we conclude that there are sex differences in glutamatergic transmission in the mPFC. Our data suggest that females have higher levels of glutamatergic transmission in this region. This provides evidence that the development of sex-specific pharmacotherapies for various psychiatric diseases is important to create more effective treatments.


Sujet(s)
Acide glutamique , Caractères sexuels , Femelle , Mâle , Souris , Animaux , Cortex préfrontal/physiologie , Potentiels post-synaptiques excitateurs , Souris de lignée C57BL
18.
Ann Neurol ; 92(4): 574-587, 2022 10.
Article de Anglais | MEDLINE | ID: mdl-35689531

RÉSUMÉ

Brain imaging is essential to the clinical care of patients with stroke, a leading cause of disability and death worldwide. Whereas advanced neuroimaging techniques offer opportunities for aiding acute stroke management, several factors, including time delays, inter-clinician variability, and lack of systemic conglomeration of clinical information, hinder their maximal utility. Recent advances in deep machine learning (DL) offer new strategies for harnessing computational medical image analysis to inform decision making in acute stroke. We examine the current state of the field for DL models in stroke triage. First, we provide a brief, clinical practice-focused primer on DL. Next, we examine real-world examples of DL applications in pixel-wise labeling, volumetric lesion segmentation, stroke detection, and prediction of tissue fate postintervention. We evaluate recent deployments of deep neural networks and their ability to automatically select relevant clinical features for acute decision making, reduce inter-rater variability, and boost reliability in rapid neuroimaging assessments, and integrate neuroimaging with electronic medical record (EMR) data in order to support clinicians in routine and triage stroke management. Ultimately, we aim to provide a framework for critically evaluating existing automated approaches, thus equipping clinicians with the ability to understand and potentially apply DL approaches in order to address challenges in clinical practice. ANN NEUROL 2022;92:574-587.


Sujet(s)
Apprentissage profond , Accident vasculaire cérébral , Humains , , Neuroimagerie/méthodes , Reproductibilité des résultats , Accident vasculaire cérébral/imagerie diagnostique , Accident vasculaire cérébral/thérapie
19.
Theranostics ; 12(9): 4459-4476, 2022.
Article de Anglais | MEDLINE | ID: mdl-35673574

RÉSUMÉ

Recent attention has focused on the use of extracellular vesicles (EVs) as biological indicators of health and disease. These small, nano-sized membrane bound vesicles are secreted from cells into the extracellular space and can be readily isolated from bodily fluids. EVs can carry various bioactive molecules as cargo including DNA, RNA, proteins, and lipids. These EVs can provide a snapshot of the cell of origin and a window of opportunity to assess normal physiological states as well as pathophysiological states. For EVs to further develop as potential biomarkers of disease, it is important to characterize whether these vesicles and their associated cargo are altered in the context of demographic factors. Here, we summarize the current literature on how demographics such as age, race, and sex affect the levels and cargo of EVs. Age and sex influence both EV cargo and concentration while race studies report differences mostly in EV protein cargo. This review also identifies areas of future research and important considerations for the clinical use of EVs as biomarkers.


Sujet(s)
Vésicules extracellulaires , Marqueurs biologiques/métabolisme , Communication cellulaire , Vésicules extracellulaires/métabolisme , Protéines/métabolisme
20.
Curr Res Food Sci ; 5: 823-834, 2022.
Article de Anglais | MEDLINE | ID: mdl-35592693

RÉSUMÉ

In the food quality and safety arena, there is a need to develop novel and sustainable methodologies that can help in the prevention of foodborne diseases. Herein, we report the development of a rapid conducting polymer strip-based sensor using Polyaniline-pectin (PANI-PEC) for the detection of Escherichia coli in milk and milk products. Polyaniline-pectin nanoparticles stabilized with biopolymer pectin were synthesized and its characterization studies such as FTIR, UV-Vis spectroscopy, electrical conductivity and particle size analysis were done. The assay parameters were optimized for the selective detection of E. coli in milk and milk products. The concentration of PANI-PEC solution immobilized/strip was optimized to be 3 mg/mL as it exhibited good sensitivity and colour intensity. Based on acid production and selectivity for E.coli, concentrations of media components like lactose, tryptophan, yeast extract, chondroitin sulphate, sodium lauryl sulphate, potassium chloride, tergitol-7, gentamycin sulphate and ampicillin trihydrate were optimized as 0.9, 0.1, 0.45, 0.015, 0.1, 2, 0.0125, 0.00016 and 0.015 respectively and sample volume was optimized to 500 µL. The developed PANI-PEC colorimetric strip-based sensor detects 0.52 ± 0.17 log CFU/mL E. coli within 10: 21 h (h). Further shelf-life study revealed that the developed PANI-PEC colorimetric sensor strips are stable at room temperature up to six months exhibiting the same sensitivity. The results obtained here indicate that this novel and simple paper based colorimetric sensor holds potential for application in food industries as a reliable and rapid method for detection of E. coli in milk and milk products at various stages of production and processing.

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