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1.
iScience ; 27(6): 110009, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38868206

ABSTRACT

Continuous assessment of the impact of SARS-CoV-2 on the host at the cell-type level is crucial for understanding key mechanisms involved in host defense responses to viral infection. We investigated host response to ancestral-strain and Alpha-variant SARS-CoV-2 infections within air-liquid-interface human nasal epithelial cells from younger adults (26-32 Y) and older children (12-14 Y) using single-cell RNA-sequencing. Ciliated and secretory-ciliated cells formed the majority of highly infected cell-types, with the latter derived from ciliated lineages. Strong innate immune responses were observed across lowly infected and uninfected bystander cells and heightened in Alpha-infection. Alpha highly infected cells showed increased expression of protein-refolding genes compared with ancestral-strain-infected cells in children. Furthermore, oxidative phosphorylation-related genes were down-regulated in bystander cells versus infected and mock-control cells, underscoring the importance of these biological functions for viral replication. Overall, this study highlights the complexity of cell-type-, age- and viral strain-dependent host epithelial responses to SARS-CoV-2.

2.
Trends Ecol Evol ; 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38862358

ABSTRACT

Many perennial plants show mast seeding, characterized by synchronous and highly variable reproduction across years. We propose a general model of masting, integrating proximate factors (environmental variation, weather cues, and resource budgets) with ultimate drivers (predator satiation and pollination efficiency). This general model shows how the relationships between masting and weather shape the diverse responses of species to climate warming, ranging from no change to lower interannual variation or reproductive failure. The role of environmental prediction as a masting driver is being reassessed; future studies need to estimate prediction accuracy and the benefits acquired. Since reproduction is central to plant adaptation to climate change, understanding how masting adapts to shifting environmental conditions is now a central question.

3.
medRxiv ; 2024 May 25.
Article in English | MEDLINE | ID: mdl-38826318

ABSTRACT

Background: Angiotensin (Ang)-II impairs the function of the antihypertensive enzyme ACE2 by promoting its internalization, ubiquitination and degradation thus contributing to hypertension. However, few ACE2 ubiquitination partners have been identified and their role in hypertension remains unknown. Methods: Proteomics and bioinformatic analysis were used to identify ACE2 ubiquitination partners in the brain, heart, and kidney from Ang-II-infused C57BL6/J mice from both sexes and validated the interaction between UBR1 and ACE2 in cells. Central and peripheral UBR1 knockdown was then performed in male mice to investigate its role in the maintenance of hypertension. Results: Proteomics analysis from hypothalamus identified UBR1 as a potential E3 ligase promoting ACE2 ubiquitination. Enhanced UBR1 expression, associated with ACE2 reduction, was confirmed in various tissues from hypertensive male mice and human samples. Treatment of endothelial and smooth muscle cells with testosterone, but not 17ß-estradiol, confirmed a sex-specific regulation of UBR1. In vivo silencing of UBR1 using chronic administration of small interference RNA resulted in the restoration of ACE2 levels in hypertensive males. A transient decrease in blood pressure following intracerebroventricular, but not systemic, infusion was also observed. Interestingly, UBR1 knockdown increased the brain activation of Nedd4-2, an E3 ligase promoting ACE2 ubiquitination and reduced expression of SGK1, the kinase inactivating Nedd4-2. Conclusions: These data demonstrate that UBR1 is a novel ubiquitin ligase targeting ACE2 in hypertension. UBR1 and Nedd4-2 E3 ligases appear to work synergistically to ubiquitinate ACE2. Targeting of these ubiquitin ligases may represent a novel strategy to restore ACE2 compensatory activity in hypertension.

4.
J Neurosci ; 2024 May 15.
Article in English | MEDLINE | ID: mdl-38749703

ABSTRACT

Dysregulation of oligodendrocyte progenitor cell (OPC) recruitment and oligodendrocyte differentiation contribute to failure of remyelination in human demyelinating diseases such as multiple sclerosis (MS). Deletion of muscarinic receptor enhances OPC differentiation and remyelination. However, the role of ligand-dependent signaling versus constitutive receptor activation is unknown. We hypothesized that dysregulated acetylcholine (ACh) release upon demyelination contributes to ligand mediated activation hindering myelin repair. Following chronic cuprizone induced demyelination (male and female mice), we observed a 2.5-fold increase in ACh concentration. This increase in ACh concentration could be attributed to increased ACh synthesis or decreased acetylcholinesterase (AChE) / butyrylcholinesterase (BChE) mediated degradation. Using ChAT reporter mice, we identified increased ChAT-GFP expression following both lysolecithin and cuprizone demyelination. ChAT-GFP expression was upregulated in a subset of injured and uninjured axons following intraspinal lysolecithin induced demyelination. In cuprizone demyelinated corpus callosum, ChAT-GFP was observed in Gfap+ astrocytes and axons indicating the potential for neuronal and astrocytic ACh release. BChE expression was significantly decreased in the corpus callosum following cuprizone demyelination. This decrease was due to the loss of myelinating oligodendrocytes which were the primary source of BChE. To determine the role of ligand mediated muscarinic signaling following lysolecithin injection, we administered neostigmine, a cholinesterase inhibitor, to artificially raise ACh. We identified a dose-dependent decrease in mature oligodendrocyte density with no effect on OPC recruitment. Together, these results support a functional role of ligand mediated activation of muscarinic receptors following demyelination and suggest that dysregulation of ACh homeostasis directly contributes to failure of remyelination in MS.Significance Statement Demyelinating diseases like Multiple Sclerosis are characterized by failure of remyelination. Oligodendrocyte progenitor cell (OPC) recruitment and differentiation are crucial aspects for remyelination to occur. Here we show that increased acetylcholine (ACh) contributes to activation of muscarinic receptors that inhibit OPC differentiation. Increased choline acetyltransferase synthesis following demyelination was observed in axons and astrocytes suggestive of a potential for acetylcholine synthesis and release. The increase in ACh levels following demyelination was largely due to reduction of oligodendrocyte derived butyrylcholinesterase that modulates ACh concentration. Development of cell specific esterase stimulator to restore ACh levels may serve as an approach towards inhibiting ongoing demyelination and neurodegeneration.

5.
Glob Chang Biol ; 30(5): e17307, 2024 May.
Article in English | MEDLINE | ID: mdl-38709196

ABSTRACT

Climate change effects on tree reproduction are poorly understood, even though the resilience of populations relies on sufficient regeneration to balance increasing rates of mortality. Forest-forming tree species often mast, i.e. reproduce through synchronised year-to-year variation in seed production, which improves pollination and reduces seed predation. Recent observations in European beech show, however, that current climate change can dampen interannual variation and synchrony of seed production and that this masting breakdown drastically reduces the viability of seed crops. Importantly, it is unclear under which conditions masting breakdown occurs and how widespread breakdown is in this pan-European species. Here, we analysed 50 long-term datasets of population-level seed production, sampled across the distribution of European beech, and identified increasing summer temperatures as the general driver of masting breakdown. Specifically, increases in site-specific mean maximum temperatures during June and July were observed across most of the species range, while the interannual variability of population-level seed production (CVp) decreased. The declines in CVp were greatest, where temperatures increased most rapidly. Additionally, the occurrence of crop failures and low seed years has decreased during the last four decades, signalling altered starvation effects of masting on seed predators. Notably, CVp did not vary among sites according to site mean summer temperature. Instead, masting breakdown occurs in response to warming local temperatures (i.e. increasing relative temperatures), such that the risk is not restricted to populations growing in warm average conditions. As lowered CVp can reduce viable seed production despite the overall increase in seed count, our results warn that a covert mechanism is underway that may hinder the regeneration potential of European beech under climate change, with great potential to alter forest functioning and community dynamics.


Subject(s)
Climate Change , Fagus , Seasons , Temperature , Fagus/growth & development , Fagus/physiology , Europe , Seeds/growth & development , Seeds/physiology , Reproduction , Trees/growth & development , Trees/physiology , Pollination
6.
J Allergy Clin Immunol Glob ; 3(2): 100241, 2024 May.
Article in English | MEDLINE | ID: mdl-38585448

ABSTRACT

Background: Reported outcomes in patients with primary immunodeficiency (PID) infected by coronavirus disease 2019 (COVID-19) have been variable owing to a combination of viral strain heterogeneity, differences in patient populations and health systems, and local availability of vaccination and specific COVID-19 therapies. There are few reports on the experience of Australian patients with PID during the pandemic. Objectives: In this retrospective study, we describe the baseline characteristics and short-term outcomes of patients with PID who were infected by COVID-19 and known to the Royal Melbourne Hospital, a major tertiary center in Victoria, Australia. Methods: Between April 2021 and April 2022, a total of 31 of 138 patients with PID were affected by COVID-19. More than half of them had 3 vaccine doses at the time of infection (which at the time was considered being fully vaccinated) and received COVID-19-targeted treatment. Results: All of the infected patients had ambulatory disease, with no cases of morbidity or mortality. In line with the current literature, the PID subtypes described did not appear to independently predict worse outcomes. Conclusions: Some protective factors include this cohort's relatively younger average age and its high uptake of vaccination and COVID-19 therapies.

7.
Blood Adv ; 8(10): 2361-2372, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38447114

ABSTRACT

ABSTRACT: Advancements in genomics are transforming the clinical management of chronic myeloid leukemia (CML) toward precision medicine. The impact of somatic mutations on treatment outcomes is still under debate. We studied the association of somatic mutations in epigenetic modifier genes and activated signaling/myeloid transcription factors (AS/MTFs) with disease progression and treatment failure in patients with CML after tyrosine kinase inhibitor (TKI) therapy. A total of 394 CML samples were sequenced, including 254 samples collected at initial diagnosis and 140 samples taken during follow-up. Single-molecule molecular inversion probe (smMIP)-based next-generation sequencing (NGS) was conducted targeting recurrently mutated loci in 40 genes, with a limit of detection of 0.2%. Seventy mutations were detected in 57 diagnostic samples (22.4%), whereas 64 mutations were detected in 39 of the follow-up samples (27.9%). Carrying any mutation at initial diagnosis was associated with worse outcomes after TKI therapy, particularly in AS/MTF genes. Patients having these mutations at initial diagnosis and treated with imatinib showed higher risks of treatment failure (hazard ratio, 2.53; 95% confidence interval, 1.13-5.66; P = .0239). The adverse prognostic impact of the mutations was not clear for patients treated with second-generation TKIs. The multivariate analysis affirmed that mutations in AS/MTF genes independently serve as adverse prognostic factors for molecular response, failure-free survival, and progression risk. Additionally, there was an observable nonsignificant trend indicating a heightened risk of progression to advanced disease and worse overall survival. In conclusion, mutations in the AS/MTF genes using smMIP-based NGS can help identify patients with a potential risk of both treatment failure and progression and may help upfront TKI selection.


Subject(s)
Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Mutation , Humans , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/mortality , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis , Male , Middle Aged , Female , Adult , Aged , Signal Transduction , Protein Kinase Inhibitors/therapeutic use , Prognosis , Transcription Factors/genetics , Treatment Outcome , High-Throughput Nucleotide Sequencing , Young Adult , Aged, 80 and over , Disease Progression
8.
Int J Infect Dis ; 141: 106969, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38387705

ABSTRACT

OBJECTIVES: To quantify the associations between invasive group A streptococcal disease (iGAS) incidence and influenza, varicella, and chronic hepatitis C virus (HCV). METHODS: We used individual-level linked data of iGAS cases from Victoria, Australia (2007-2017) to assess associations between these viral infections and iGAS. A self-controlled case series method was used to estimate the relative incidence of iGAS following an influenza or varicella infection, while the relative incidence of iGAS among HCV cases, and HCV cases who inject drugs, was estimated using population-level data and a negative binomial regression model. RESULTS: Of the 1949 individuals with at least one iGAS diagnosis, 82 were diagnosed with influenza at least once, 30 with varicella, and 118 with HCV during the study period. The relative incidence of iGAS increased substantially following infection with influenza (incidence rate ratio [IRR]: 34.5, 95% confidence interval [CI]: 21.3-55.8) or varicella (IRR: 22.4, 95% CI: 10.3-48.8). iGAS incidence was higher among HCV cases (IRR: 5.7, 95% CI: 4.4-7.3) compared to individuals without HCV. iGAS incidence was also higher among HCV cases who inject drugs (IRR: 17.9, 95% CI: 13.0-24.4) compared to individuals without HCV who did not inject drugs. CONCLUSIONS: We found a significantly higher risk of iGAS following an influenza or varicella infection and for chronic HCV cases, particularly those who inject drugs. These findings are relevant to public health practice and support the timely identification of iGAS cases.


Subject(s)
Chickenpox , Hepatitis C, Chronic , Hepatitis C , Influenza, Human , Streptococcal Infections , Substance Abuse, Intravenous , Humans , Victoria/epidemiology , Hepacivirus , Influenza, Human/complications , Influenza, Human/epidemiology , Chickenpox/complications , Chickenpox/epidemiology , Streptococcal Infections/complications , Streptococcal Infections/epidemiology , Streptococcus pyogenes , Incidence , Hepatitis C/complications , Hepatitis C/epidemiology
9.
Diabet Med ; 41(5): e15254, 2024 May.
Article in English | MEDLINE | ID: mdl-38010056

ABSTRACT

AIMS: Both parent and adolescent involvement in type 1 diabetes management are critical during adolescence. The current study sought to understand the factors associated with parent and adolescent satisfaction with their own and one another's involvement in diabetes management. METHODS: Cross-sectional baseline data from 157 parent-adolescent dyads enrolled in an RCT were used. Adolescent ages ranged from 12 to 19 (Mage = 14.7, SD = 1.89) and were balanced by gender (50.3% male). Paired t-tests examined concordance between parent and adolescent satisfaction, bivariate correlations identified correlates, and regressions examined unique associations. RESULTS: Roughly, 43% of adolescents and 29% of parents were very satisfied with adolescent involvement in diabetes management, whereas 71% of adolescents and 26.1% of parents were very satisfied with parent involvement. Indicators of better glycaemic health (via higher percent time-in-range and lower HbA1c and percent time in hyperglycaemia) and psychosocial functioning (less diabetes distress and depression) were correlated with higher satisfaction. Parent satisfaction with adolescent involvement was higher among older adolescents (R = 0.198, p = 0.013). Non-Hispanic white youth were more satisfied with their own involvement than youth of colour (t(149) = -2.783, p = 0.003). Both percent time-in-range and one's own diabetes distress uniquely related to parent and adolescent satisfaction with adolescent involvement. Conversely, parent satisfaction with their own involvement was only uniquely associated with parent diabetes distress. CONCLUSION: Both adolescent and parents' satisfaction with adolescents' involvement in self-management are indicators of both glycaemic control and psychosocial well-being, whereas parents' self-evaluations are more closely tied to diabetes-specific distress.


Subject(s)
Adolescent Behavior , Diabetes Mellitus, Type 1 , Hyperglycemia , Humans , Male , Adolescent , Female , Cross-Sectional Studies , Parents/psychology , Diabetes Mellitus, Type 1/therapy , Diabetes Mellitus, Type 1/psychology , Parent-Child Relations
10.
Radiology ; 309(1): e222691, 2023 10.
Article in English | MEDLINE | ID: mdl-37874241

ABSTRACT

Background Despite variation in performance characteristics among radiologists, the pairing of radiologists for the double reading of screening mammograms is performed randomly. It is unknown how to optimize pairing to improve screening performance. Purpose To investigate whether radiologist performance characteristics can be used to determine the optimal set of pairs of radiologists to double read screening mammograms for improved accuracy. Materials and Methods This retrospective study was performed with reading outcomes from breast cancer screening programs in Sweden (2008-2015), England (2012-2014), and Norway (2004-2018). Cancer detection rates (CDRs) and abnormal interpretation rates (AIRs) were calculated, with AIR defined as either reader flagging an examination as abnormal. Individual readers were divided into performance categories based on their high and low CDR and AIR. The performance of individuals determined the classification of pairs. Random pair performance, for which any type of pair was equally represented, was compared with the performance of specific pairing strategies, which consisted of pairs of readers who were either opposite or similar in AIR and/or CDR. Results Based on a minimum number of examinations per reader and per pair, the final study sample consisted of 3 592 414 examinations (Sweden, n = 965 263; England, n = 837 048; Norway, n = 1 790 103). The overall AIRs and CDRs for all specific pairing strategies (Sweden AIR range, 45.5-56.9 per 1000 examinations and CDR range, 3.1-3.6 per 1000; England AIR range, 68.2-70.5 per 1000 and CDR range, 8.9-9.4 per 1000; Norway AIR range, 81.6-88.1 per 1000 and CDR range, 6.1-6.8 per 1000) were not significantly different from the random pairing strategy (Sweden AIR, 54.1 per 1000 examinations and CDR, 3.3 per 1000; England AIR, 69.3 per 1000 and CDR, 9.1 per 1000; Norway AIR, 84.1 per 1000 and CDR, 6.3 per 1000). Conclusion Pairing a set of readers based on different pairing strategies did not show a significant difference in screening performance when compared with random pairing. © RSNA, 2023.


Subject(s)
Mammography , Physical Examination , Humans , Retrospective Studies , England , Radiologists
11.
JAMA Dermatol ; 159(11): 1275-1277, 2023 11 01.
Article in English | MEDLINE | ID: mdl-37792338

ABSTRACT

This case-control study compares the prevalence of fibromyalgia between adults with hidradenitis suppurativa and adults with non­pain-related conditions.


Subject(s)
Fibromyalgia , Hidradenitis Suppurativa , Humans , Hidradenitis Suppurativa/complications , Hidradenitis Suppurativa/diagnosis , Fibromyalgia/complications , Fibromyalgia/diagnosis
12.
Commun Med (Lond) ; 3(1): 132, 2023 Oct 05.
Article in English | MEDLINE | ID: mdl-37794113

ABSTRACT

BACKGROUND: The greatest change in the treatment of people living with type 1 diabetes in the last decade has been the explosion of technology assisting in all aspects of diabetes therapy, from glucose monitoring to insulin delivery and decision making. As such, the aim of our systematic review was to assess the utility of these technologies as well as identify any precision medicine-directed findings to personalize care. METHODS: Screening of 835 peer-reviewed articles was followed by systematic review of 70 of them (focusing on randomized trials and extension studies with ≥50 participants from the past 10 years). RESULTS: We find that novel technologies, ranging from continuous glucose monitoring systems, insulin pumps and decision support tools to the most advanced hybrid closed loop systems, improve important measures like HbA1c, time in range, and glycemic variability, while reducing hypoglycemia risk. Several studies included person-reported outcomes, allowing assessment of the burden or benefit of the technology in the lives of those with type 1 diabetes, demonstrating positive results or, at a minimum, no increase in self-care burden compared with standard care. Important limitations of the trials to date are their small size, the scarcity of pre-planned or powered analyses in sub-populations such as children, racial/ethnic minorities, people with advanced complications, and variations in baseline glycemic levels. In addition, confounders including education with device initiation, concomitant behavioral modifications, and frequent contact with the healthcare team are rarely described in enough detail to assess their impact. CONCLUSIONS: Our review highlights the potential of technology in the treatment of people living with type 1 diabetes and provides suggestions for optimization of outcomes and areas of further study for precision medicine-directed technology use in type 1 diabetes.


In the last decade, there have been significant advances in how technology is used in the treatment of people living with type 1 diabetes. These technologies primarily aim to help manage blood sugar levels. Here, we reviewed research published over the last decade to evaluate the impact of such technologies on type 1 diabetes treatment. We find that various types of novel technologies, such as devices to monitor blood sugar levels continuously or deliver insulin, improve important diabetes-related measures and can reduce the risk of having low blood sugar levels. Importantly, several studies showed a positive impact of technologies on quality of life in people living with diabetes. Our findings highlight the benefits of novel technologies in the treatment of type 1 diabetes and identify areas for further research to optimize and personalize diabetes care.

13.
Nat Med ; 29(10): 2438-2457, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37794253

ABSTRACT

Precision medicine is part of the logical evolution of contemporary evidence-based medicine that seeks to reduce errors and optimize outcomes when making medical decisions and health recommendations. Diabetes affects hundreds of millions of people worldwide, many of whom will develop life-threatening complications and die prematurely. Precision medicine can potentially address this enormous problem by accounting for heterogeneity in the etiology, clinical presentation and pathogenesis of common forms of diabetes and risks of complications. This second international consensus report on precision diabetes medicine summarizes the findings from a systematic evidence review across the key pillars of precision medicine (prevention, diagnosis, treatment, prognosis) in four recognized forms of diabetes (monogenic, gestational, type 1, type 2). These reviews address key questions about the translation of precision medicine research into practice. Although not complete, owing to the vast literature on this topic, they revealed opportunities for the immediate or near-term clinical implementation of precision diabetes medicine; furthermore, we expose important gaps in knowledge, focusing on the need to obtain new clinically relevant evidence. Gaps include the need for common standards for clinical readiness, including consideration of cost-effectiveness, health equity, predictive accuracy, liability and accessibility. Key milestones are outlined for the broad clinical implementation of precision diabetes medicine.


Subject(s)
Diabetes Mellitus , Precision Medicine , Humans , Consensus , Diabetes Mellitus/diagnosis , Diabetes Mellitus/genetics , Diabetes Mellitus/therapy , Evidence-Based Medicine
14.
Article in English | MEDLINE | ID: mdl-37284179

ABSTRACT

Electrocardiographic imaging (ECGI) presents a clinical opportunity to noninvasively understand the sources of arrhythmias for individual patients. To help increase the effectiveness of ECGI, we provide new ways to visualize associated measurement and modeling errors. In this paper, we study source localization uncertainty in two steps: First, we perform Monte Carlo simulations of a simple inverse ECGI source localization model with error sampling to understand the variations in ECGI solutions. Second, we present multiple visualization techniques, including confidence maps, level-sets, and topology-based visualizations, to better understand uncertainty in source localization. Our approach offers a new way to study uncertainty in the ECGI pipeline.

15.
J Diabetes Complications ; 37(7): 108514, 2023 07.
Article in English | MEDLINE | ID: mdl-37263033

ABSTRACT

AIM: Youth from lower socioeconomic status (SES) have suboptimal type 1 diabetes (T1D) outcomes. Patient reported outcomes (PROs) measure psychosocial states and are associated with T1D outcomes, however are understudied in low SES youth. We aimed to evaluate associations between PROs and public insurance status, a proxy for low SES. METHODS: We analyzed survey data from 129 youth with T1D (age 15.7 ± 2.3 years, 33 % publicly insured) screened with PROMIS Global Health (PGH, measuring global health) and Patient Health Questionnaire (PHQ-9, measuring depressive symptoms) during diabetes appointments. Correlation and regression analyses evaluated differences in PGH and PHQ-9 by insurance status. RESULTS: For youth with public insurance, lower global health correlated with lower self-monitoring blood glucose (SMBG; r = 0.38,p = 0.033) and older age (r = -0.45,p = 0.005). In youth with private insurance, lower global health correlated with lower SMBG (r = 0.27,p = 0.018) and female sex (rho = 0.26,p = 0.015). For youth with private insurance, higher depressive symptoms correlated with higher body mass index (r = 0.22,p = 0.03) and fewer SMBG (r = -0.35,p = 0.04). In multivariate regression analyses, public insurance was inversely associated with global health (p = 0.027). CONCLUSION: PGH is a particularly salient PRO in youth with public insurance. Global health may be an important psychosocial factor to assess in youth with T1D from low SES backgrounds.


Subject(s)
Diabetes Mellitus, Type 1 , Humans , Adolescent , Female , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/diagnosis , Diabetes Mellitus, Type 1/epidemiology , Surveys and Questionnaires , Social Class , Blood Glucose , Patient Reported Outcome Measures
16.
Drug Metab Dispos ; 51(9): 1196-1206, 2023 09.
Article in English | MEDLINE | ID: mdl-37349115

ABSTRACT

Liver cytochrome P450s (CYPs) of the endoplasmic reticulum (ER) are involved in the metabolism of exogenous and endogenous chemicals. The ER is not uniform, but possesses ordered lipid microdomains containing higher levels of saturated fatty acids, sphingomyelin, and cholesterol and disordered regions containing higher levels of polyunsaturated fatty acid chains. The various forms of drug-metabolizing P450s partition to either the ordered or disordered lipid microdomains with different degrees of specificity. P450s readily form complexes with ER-resident proteins, including other forms of P450. This study aims to ascertain whether lipid microdomain localization influences protein-P450 interactions in rat liver microsomes. Thus, liver microsomes were co-immunoprecipitated with CYP1A2-specific and CYP3A-specific antibodies, and the co-immunoprecipitating proteins were identified by liquid chromatography mass spectrometry proteomic analysis. These two P450s preferentially partition to ordered and disordered microdomains, respectively. More than 100 proteins were co-immunoprecipitated with each P450. Segregation of proteins into different microdomains did not preclude their interaction. However, CYP3A interacted broadly with proteins from ordered microdomains, whereas CYP1A2 reacted with a limited subset of these proteins. This is consistent with the concept of lipid raft heterogeneity and may indicate that CYP1A2 is targeted to a specific type of lipid raft. Although many of the interacting proteins for both P450s were other-drug metabolizing enzymes, other interactions were also evident. The consistent CYP3A binding partners were predominantly involved in phase I/II drug metabolism; however, CYP1A2 interacted not only with xenobiotic metabolizing enzymes, but also with enzymes involved in diverse cellular responses such as ER stress and protein folding. SIGNIFICANCE STATEMENT: This work describes the protein interactomes in rat liver microsomes of two important cytochromes P450s (CYP1A2 and CYP3A) in drug metabolism and describes the relationship of the interacting proteins to lipid microdomain distribution.


Subject(s)
Cytochrome P-450 CYP1A2 , Microsomes, Liver , Rats , Animals , Cytochrome P-450 CYP1A2/metabolism , Microsomes, Liver/metabolism , Cytochrome P-450 CYP3A/metabolism , Proteomics , Cytochrome P-450 Enzyme System/metabolism , Lipids
17.
Cardiovasc Res ; 119(11): 2130-2141, 2023 09 05.
Article in English | MEDLINE | ID: mdl-37161607

ABSTRACT

AIMS: Angiotensin-converting enzyme 2 (ACE2) is a critical component of the compensatory renin-angiotensin system that is down-regulated during the development of hypertension, possibly via ubiquitination. However, little is known about the mechanisms involved in ACE2 ubiquitination in neurogenic hypertension. This study aimed at identifying ACE2 ubiquitination partners, establishing causal relationships and clinical relevance, and testing a gene therapy strategy to mitigate ACE2 ubiquitination in neurogenic hypertension. METHODS AND RESULTS: Bioinformatics and proteomics were combined to identify E3 ubiquitin ligases associated with ACE2 ubiquitination in chronically hypertensive mice. In vitro gain/loss of function experiments assessed ACE2 expression and activity to validate the interaction between ACE2 and the identified E3 ligase. Mutation experiments were further used to generate a ubiquitination-resistant ACE2 mutant (ACE2-5R). Optogenetics, blood pressure telemetry, pharmacological blockade of GABAA receptors in mice expressing ACE2-5R in the bed nucleus of the stria terminalis (BNST), and capillary western analysis were used to assess the role of ACE2 ubiquitination in neurogenic hypertension. Ubiquitination was first validated as leading to ACE2 down-regulation, and Neural precursor cell-expressed developmentally down-regulated protein 4-2 (Nedd4-2) was identified as a E3 ligase up-regulated in hypertension and promoting ACE2 ubiquitination. Mutation of lysine residues in the C-terminal of ACE2 was associated with increased activity and resistance to angiotensin (Ang)-II-mediated degradation. Mice transfected with ACE2-5R in the BNST exhibited enhanced GABAergic input to the paraventricular nucleus (PVN) and a reduction in hypertension. ACE2-5R expression was associated with reduced Nedd4-2 levels in the BNST. CONCLUSION: Our data identify Nedd4-2 as the first E3 ubiquitin ligase involved in ACE2 ubiquitination in Ang-II-mediated hypertension. We demonstrate the pivotal role of ACE2 on GABAergic neurons in the maintenance of an inhibitory tone to the PVN and the regulation of pre-sympathetic activity. These findings provide a new working model where Nedd4-2 could contribute to ACE2 ubiquitination, leading to the development of neurogenic hypertension and highlighting potential novel therapeutic strategies.


Subject(s)
Angiotensin-Converting Enzyme 2 , Hypertension , Animals , Mice , Angiotensin II/metabolism , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/metabolism , Hypertension/metabolism , Peptidyl-Dipeptidase A/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Ubiquitination , Up-Regulation
18.
J Diabetes ; 15(7): 597-606, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37139842

ABSTRACT

BACKGROUND: DiabetesWise is an unbranded, data-driven online resource that tailors device recommendations based on preferences and priorities of people with insulin-requiring diabetes. The objective of this study is to examine whether DiabetesWise increases uptake of diabetes devices, which are empirically supported to improve glycemic and psychosocial outcomes. METHODS: The sample included 458 participants (Mage = 37.1, SD = 9.73; 66% female; 81% type 1 diabetes) with insulin-requiring diabetes and minimal diabetes device use at enrollment. Participants used DiabetesWise and completed online surveys. Chi-square and t tests evaluated requests for a device prescription, receiving a prescription, and starting a new device at 1 and 3 months post use. Baseline predictors of these variables and past use of continuous glucose monitors (CGMs) and changes in diabetes distress post use were also examined. RESULTS: Within the first month of interacting with DiabetesWise 19% of participants asked for a prescription for a diabetes device. This rate rose to 31% in the first 3 months. These requests resulted in 16% of the sample starting a new device within the first 3 months. Whereas several factors were associated with prior CGM use, receiving a prescription, and starting a new device, more diabetes distress (t(343) = -3.13, p = .002) was the only factor associated with asking for a prescription. Diabetes distress decreased after interacting with DiabetesWise within 1 month (t(193) = 3.51, p < .001) and 3 months (t(180) = 5.23, p < .001). CONCLUSIONS: Within 3 months of interacting with DiabetesWise, one in three participants had requested a prescription for a new diabetes device and average distress levels were reduced, indicating benefit from this low-intensity online platform.


Subject(s)
Diabetes Mellitus, Type 1 , Humans , Female , Adult , Male , Diabetes Mellitus, Type 1/drug therapy , Blood Glucose , Insulin/therapeutic use , Blood Glucose Self-Monitoring , Insulin Infusion Systems/psychology , Hypoglycemic Agents/therapeutic use
19.
Viruses ; 15(3)2023 03 21.
Article in English | MEDLINE | ID: mdl-36992502

ABSTRACT

Despite the suppression of human immunodeficiency virus (HIV) replication by combined antiretroviral therapy (cART), 50-60% of HIV-infected patients suffer from HIV-associated neurocognitive disorders (HAND). Studies are uncovering the role of extracellular vesicles (EVs), especially exosomes, in the central nervous system (CNS) due to HIV infection. We investigated links among circulating plasma exosomal (crExo) proteins and neuropathogenesis in simian/human immunodeficiency virus (SHIV)-infected rhesus macaques (RM) and HIV-infected and cART treated patients (Patient-Exo). Isolated EVs from SHIV-infected (SHIV-Exo) and uninfected (CTL-Exo) RM were predominantly exosomes (particle size < 150 nm). Proteomic analysis quantified 5654 proteins, of which 236 proteins (~4%) were significantly, differentially expressed (DE) between SHIV-/CTL-Exo. Interestingly, different CNS cell specific markers were abundantly expressed in crExo. Proteins involved in latent viral reactivation, neuroinflammation, neuropathology-associated interactive as well as signaling molecules were expressed at significantly higher levels in SHIV-Exo than CTL-Exo. However, proteins involved in mitochondrial biogenesis, ATP production, autophagy, endocytosis, exocytosis, and cytoskeleton organization were significantly less expressed in SHIV-Exo than CTL-Exo. Interestingly, proteins involved in oxidative stress, mitochondrial biogenesis, ATP production, and autophagy were significantly downregulated in primary human brain microvascular endothelial cells exposed with HIV+/cART+ Patient-Exo. We showed that Patient-Exo significantly increased blood-brain barrier permeability, possibly due to loss of platelet endothelial cell adhesion molecule-1 protein and actin cytoskeleton structure. Our novel findings suggest that circulating exosomal proteins expressed CNS cell markers-possibly associated with viral reactivation and neuropathogenesis-that may elucidate the etiology of HAND.


Subject(s)
HIV Infections , HIV-1 , Simian Acquired Immunodeficiency Syndrome , Simian Immunodeficiency Virus , Animals , Humans , Macaca mulatta , HIV Infections/complications , Simian Acquired Immunodeficiency Syndrome/complications , Endothelial Cells , Proteomics , Disease Models, Animal , Adenosine Triphosphate , Viral Load
20.
Oecologia ; 201(2): 385-396, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36637523

ABSTRACT

Within and among populations, alkaloid defenses of the strawberry poison frog (Oophaga pumilio) vary spatially, temporally, and with life history stage. Natural variation in defense has been implicated as a critical factor in determining the level of protection afforded against predators and pathogens. Oophaga pumilio tadpoles sequester alkaloids from nutritive eggs and are, thus, entirely dependent on their mothers for their defense. However, it remains unclear how tadpole alkaloid composition relates to that of its mother and how variation in maternally provisioned defenses might result in varying levels of protection against predators. Here, we demonstrate that natural variation in the alkaloid composition of a mother frog is reflected as variation in her tadpole's alkaloid composition. Tadpoles, like mother frogs, varied in their alkaloid composition but always contained the identical alkaloids found in their mother. Alkaloid quantity in tadpoles was highly correlated with alkaloid quantity in their mothers. Additionally, alkaloid quantity was the best predictor of tadpole palatability, wherein tadpoles with higher alkaloid quantities were less palatable. Mother frogs with greater quantities of alkaloids are, thus, providing better protection for their offspring by provisioning chemical defenses during one of the most vulnerable periods of life.


Subject(s)
Alkaloids , Poisons , Animals , Female , Humans , Anura , Larva , Mothers
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