Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 50
Filtrar
1.
EMBO Mol Med ; 15(12): e18526, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-37971164

RESUMEN

Aging results from the accumulation of molecular damage that impairs normal biochemical processes. We previously reported that age-linked damage to amino acid sequence NGR (Asn-Gly-Arg) results in "gain-of-function" conformational switching to isoDGR (isoAsp-Gly-Arg). This integrin-binding motif activates leukocytes and promotes chronic inflammation, which are characteristic features of age-linked cardiovascular disorders. We now report that anti-isoDGR immunotherapy mitigates lifespan reduction of Pcmt1-/- mouse. We observed extensive accumulation of isoDGR and inflammatory cytokine expression in multiple tissues from Pcmt1-/- and naturally aged WT animals, which could also be induced via injection of isoDGR-modified plasma proteins or synthetic peptides into young WT animals. However, weekly injection of anti-isoDGR mAb (1 mg/kg) was sufficient to significantly reduce isoDGR-protein levels in body tissues, decreased pro-inflammatory cytokine concentrations in blood plasma, improved cognition/coordination metrics, and extended the average lifespan of Pcmt1-/- mice. Mechanistically, isoDGR-mAb mediated immune clearance of damaged isoDGR-proteins via antibody-dependent cellular phagocytosis (ADCP). These results indicate that immunotherapy targeting age-linked protein damage may represent an effective intervention strategy in a range of human degenerative disorders.


Asunto(s)
Citocinas , Longevidad , Humanos , Animales , Ratones , Anciano , Secuencia de Aminoácidos , Unión Proteica
2.
iScience ; 26(7): 107047, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37360691

RESUMEN

We examined the effects of ∼30 days of spaceflight on glycogen synthase kinase 3 (GSK3) content and inhibitory serine phosphorylation in murine muscle and bone samples from four separate missions (BION-M1, rodent research [RR]1, RR9, and RR18). Spaceflight reduced GSK3ß content across all missions, whereas its serine phosphorylation was elevated with RR18 and BION-M1. The reduction in GSK3ß was linked to the reduction in type IIA fibers commonly observed with spaceflight as these fibers are particularly enriched with GSK3. We then tested the effects of inhibiting GSK3 before this fiber type shift, and we demonstrate that muscle-specific Gsk3 knockdown increased muscle mass, preserved muscle strength, and promoted the oxidative fiber type with Earth-based hindlimb unloading. In bone, GSK3 activation was enhanced after spaceflight; and strikingly, muscle-specific Gsk3 deletion increased bone mineral density in response to hindlimb unloading. Thus, future studies should test the effects of GSK3 inhibition during spaceflight.

3.
J Leukoc Biol ; 114(1): 92-105, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37141385

RESUMEN

Mast cells are leukocytes that mediate various aspects of immunity and drive allergic hypersensitivity pathologies. Mast cells differentiate from hematopoietic progenitor cells in a manner that is largely IL-3 dependent. However, molecular mechanisms, including the signaling pathways that control this process, have yet to be thoroughly investigated. Here, we examine the role of the ubiquitous and critical mitogen-activated protein kinase signaling pathway due to its position downstream of the IL-3 receptor. Hematopoietic progenitor cells were harvested from the bone marrow of C57BL/6 mice and differentiated to bone marrow-derived mast cells in the presence of IL-3 and mitogen-activated protein kinase inhibitors. Inhibition of the JNK node of the mitogen-activated protein kinase pathway induced the most comprehensive changes to the mature mast cell phenotype. Bone marrow-derived mast cells differentiated during impaired JNK signaling expressed impaired c-kit levels on the mast cell surface, first detected at week 3 of differentiation. Following 1 wk of inhibitor withdrawal and subsequent stimulation of IgE-sensitized FcεRI receptors with allergen (TNP-BSA) and c-kit receptors with stem cell factor, JNK-inhibited bone marrow-derived mast cells exhibited impediments in early-phase mediator release through degranulation (80% of control), as well as late-phase secretion of CCL1, CCL2, CCL3, TNF, and IL-6. Experiments with dual stimulation conditions (TNP-BSA + stem cell factor or TNP-BSA alone) showed that impediments in mediator secretion were found to be mechanistically linked to reduced c-kit surface levels. This study is the first to implicate JNK activity in IL-3-mediated mast cell differentiation and also identifies development as a critical and functionally determinative period.


Asunto(s)
Mastocitos , Factor de Células Madre , Animales , Ratones , Degranulación de la Célula , Diferenciación Celular , Interleucina-3/metabolismo , Mastocitos/metabolismo , Ratones Endogámicos C57BL , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas Proto-Oncogénicas c-kit/metabolismo , Receptores de IgE/metabolismo , Factor de Células Madre/metabolismo
4.
Am J Physiol Heart Circ Physiol ; 324(6): H791-H803, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36961488

RESUMEN

The effect of adverse childhood experiences (ACEs) on left ventricular mass (LVM) and left ventricular function remains largely unknown across the lifespan. This study investigated the influence of ACEs on LVM and left ventricular function and whether inflammation influences this relationship. Two hundred forty-eight healthy young adults participated and a final sample of 217 (age, 22.6 ± 0.1 yr; females, 114) had complete data. Echocardiographic assessment of LVM was indexed to height2.7 (LVMHT) and body surface area (LVMBSA). Ejection fraction (EF) and fractional shortening were also assessed. Interleukin-6 (IL-6), C-reactive protein, tumor necrosis factor-α, and matrix metalloproteinase (MMP) 1-3 were measured and ACEs exposures were assessed based on exposure and nonexposure to childhood household dysfunction and maltreatment, and quantity of adversity, (i.e., <4 ACEs and ≥4 ACEs). Individuals who experienced household dysfunction demonstrated lower LVM, LVMHT, and LVMBSA (P < 0.01) and greater IL-6 (P < 0.05) than those who did not experience household dysfunction. Reduced MMP3 was present in individuals who experienced maltreatment (P < 0.05) and ≥4 ACEs (P < 0.01) compared with no maltreatment and <4 ACEs, respectively. After controlling for covariates (i.e., sex, recent life stress, height, body mass index, smoking, physical activity, and inflammation), a significant negative effect of household dysfunction on LVM, LVMHT, and LVMBSA persisted. Likewise, a negative effect on EF independent of covariates was observed in individuals who experienced ≥4 ACEs. As such, alterations in LVM and EF may be perpetuated through a toxic home environment, promoting left ventricular underdevelopment in young adulthood. The effect of which in midlife and beyond requires additional investigation.NEW & NOTEWORTHY This is the first study to investigate the influence of adverse childhood experiences (ACEs) on left ventricular mass (LVM) and function. We identified experiencing any childhood household dysfunction was associated with lower LVM in young adults independent of sex, recent life stress, BMI and height, smoking, physical activity, and inflammation. We speculate an inflection point in LVM occurs in midlife predisposing these individuals toward a hypertrophic profile and elevated risk of heart disease in later life, although this requires longitudinal investigation.


Asunto(s)
Ventrículos Cardíacos , Interleucina-6 , Femenino , Adulto Joven , Humanos , Adulto , Ventrículos Cardíacos/diagnóstico por imagen , Función Ventricular Izquierda , Ecocardiografía , Inflamación
5.
FASEB J ; 37(2): e22748, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36624659

RESUMEN

Mast cells are granulocytic immune sentinels present in vascularized tissues that drive chronic inflammatory mechanisms characteristic of allergic pathologies. IgE-mediated mast cell activation leads to a rapid mobilization of Ca2+ from intracellular stores, which is essential for the release of preformed mediators via degranulation and de novo synthesized proinflammatory cytokines and chemokines. Given its potent signaling capacity, the dynamics of Ca2+ localization are highly regulated by various pumps and channels controlling cytosolic Ca2+ concentrations. Among these is sarco/endoplasmic reticulum Ca2+ -ATPase (SERCA), which functions to maintain low cytosolic Ca2+ concentrations by actively transporting cytosolic Ca2+ ions into the endoplasmic reticulum. In this study, we characterized the role of SERCA in allergen-activated mast cells using IgE-sensitized bone marrow-derived mast cells (BMMCs) treated with the SERCA activating compound, CDN1163, and simultaneously stimulated with allergen through FcεRI under stem cell factor (SCF) potentiation. Acute treatment with CDN1163 was found to attenuate early phase mast cell degranulation along with reactive oxygen species (ROS) production. Additionally, treatment with CDN1163 significantly reduced secretion of IL-6, IL-13, and CCL3, suggesting a role for SERCA in the late phase mast cell response. The protective effects of SERCA activation via CDN1163 treatment on the early and late phase mast cell response may be driven by the selective suppression of p38 MAPK signaling. Together, these findings implicate SERCA as an important regulator of the mast cell response to allergen and suggest SERCA activity may offer therapeutic potential targeting allergic pathologies, warranting further investigation.


Asunto(s)
Mastocitos , Transducción de Señal , Especies Reactivas de Oxígeno , Inmunoglobulina E , Degranulación de la Célula
6.
J Biol Chem ; 299(4): 102867, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36608933

RESUMEN

Mast cells are essential regulators of inflammation most recognized for their central role in allergic inflammatory disorders. Signaling via the high-affinity immunoglobulin E (IgE) receptor, FcεRI, leads to rapid degranulation of preformed granules and the sustained release of newly synthesized proinflammatory mediators. Our group recently established rosemary extract as a potent regulator of mast cell functions, attenuating MAPK and NF-κB signaling. Carnosic acid (CA)-a major polyphenolic constituent of rosemary extract-has been shown to exhibit anti-inflammatory effects in other immune cell models, but its role as a potential modulator of mast cell activation is undefined. Therefore, we sought here to determine the modulatory effects of CA in a mast cell model of allergic inflammation. We sensitized bone marrow-derived mast cells with anti-trinitrophenyl IgE and activated with allergen (TNP-BSA) under stem cell factor potentiation, in addition to treatment with CA. Our results indicate that CA significantly inhibits allergen-induced early phase responses including Ca2+ mobilization, ROS production, and subsequent degranulation. We also show CA treatment reduced late phase responses, including the release of all cytokines and chemokines examined following IgE stimulation and corresponding gene expression excepting that of CCL2. Importantly, we determined that CA mediates its inhibitory effects through modulation of tyrosine kinase Syk and downstream effectors TAK1 (Ser412) and Akt (Ser473) as well as NFκB signaling, while phosphorylation of FcεRI (γ chain) and MAPK proteins remained unaltered. These novel findings establish CA as a potent modulator of mast cell activation, warranting further investigation as a putative anti-allergy therapeutic.


Asunto(s)
Abietanos , Hipersensibilidad , Mediadores de Inflamación , Mastocitos , Humanos , Alérgenos , Degranulación de la Célula , Inmunoglobulina E , Inflamación/metabolismo , Mediadores de Inflamación/metabolismo , Mastocitos/efectos de los fármacos , Mastocitos/metabolismo , FN-kappa B/metabolismo , Receptores de IgE/metabolismo , Quinasa Syk/metabolismo , Abietanos/farmacología
7.
Am J Physiol Regul Integr Comp Physiol ; 324(3): R425-R434, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36693169

RESUMEN

Adverse childhood experiences (ACEs) are associated with greater prevalence of cardiovascular disease and altered acute stress reactivity. The current study investigated the effect of ACEs on hemodynamic and autonomic responses to orthostatic stress imposed by 60° head-up tilt (HUT) in young adults. Two-hundred twenty-six healthy young adults (age = 22.6 ± 1.5 yr; n = 116 females) without cardiovascular disease participated and had complete data. Participants underwent supine blood pressure (BP), R-R interval (RRI), cardiac output (CO), total peripheral resistance (TPR), and cardiovagal baroreflex sensitivity (cvBRS) testing followed by a transition to 60° HUT where measures were reassessed. Childhood adversity exposures were assessed based on categorical exposure and nonexposure to childhood household dysfunction and maltreatment, and <4 and ≥4 types of ACEs. Significantly greater increases in SBP (P < 0.05), DBP, MAP, and TPR (P < 0.01; all) following 60° HUT were observed in individuals with ≥4 compared with those with <4 types of ACEs. Attenuated decreases in RRI and cvBRS were observed in those with ≥4 types of ACEs (P < 0.05). Experiencing ≥4 types of ACEs was associated with augmented BP and TPR reactivity and a blunted decrease in cvBRS in response to 60° HUT in young adults. Results suggest that a reduced vagal response to orthostatic stress is present in those who have experienced ≥4 types of ACEs that may promote autonomic dysfunction. Future research examining the sympathetic and vagal baroreflex branches is warranted.


Asunto(s)
Experiencias Adversas de la Infancia , Enfermedades del Sistema Nervioso Autónomo , Enfermedades Cardiovasculares , Femenino , Humanos , Adulto Joven , Adulto , Presión Sanguínea/fisiología , Pruebas de Mesa Inclinada , Sistema Nervioso Autónomo , Frecuencia Cardíaca/fisiología
8.
Eur J Immunol ; 53(1): e2250104, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36349527

RESUMEN

Mast cells are granulated immune sentinels responsible for allergic inflammation. Allergen-induced FcεRI-signaling leads to rapid degranulation in the early-phase and sustained production and release of pro-inflammatory mediators in the late phase. Glycogen synthase kinase 3 (GSK3) is a constitutively active serine/threonine kinase and a central molecular convergence point for several pro-inflammatory pathways. GSK3 inhibition has been shown to reduce inflammation but has not yet been fully characterized in mast cell activation. Therefore, the objective of this study was to evaluate GSK3 as a putative therapeutic target in allergic inflammation using the GSK3 inhibitor, CHIR99021. Here, we found that GSK3 inhibition impaired ROS production and degranulation. Through modulation of MKK4-JNK, c-jun, and NF-κB signaling, GSK3 inhibition reduced the production/release of IL-6, IL-13, TNF, and CCL1, while only the release of CCL2 and CCL3 was impaired. Furthermore, CHIR99021-mediated GSK3 inhibition altered the pro-inflammatory phenotype of mast cells, reducing c-kit receptor levels. This implicated GSK3 in FcεRI signaling, reducing release of IL-6, TNF, and CCL1 when stimulated through FcεRI, while CCL2 and CCL3 remained unaffected, and were increased when stimulated with SCF only. These results identify GSK3 as a potential therapeutic target of utility warranting further consideration in contexts of pathological mast cell activation.


Asunto(s)
Alérgenos , Glucógeno Sintasa Quinasa 3 , Humanos , Mastocitos , Interleucina-6/metabolismo , Receptores de IgE , Inflamación/metabolismo , Degranulación de la Célula
9.
Curr Neuropharmacol ; 21(4): 891-910, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35236261

RESUMEN

Lithium is most well-known for its mood-stabilizing effects in the treatment of bipolar disorder. Due to its narrow therapeutic window (0.5-1.2 mM serum concentration), there is a stigma associated with lithium treatment and the adverse effects that can occur at therapeutic doses. However, several studies have indicated that doses of lithium under the predetermined therapeutic dose used in bipolar disorder treatment may have beneficial effects not only in the brain but across the body. Currently, literature shows that low-dose lithium (≤0.5 mM) may be beneficial for cardiovascular, musculoskeletal, metabolic, and cognitive function, as well as inflammatory and antioxidant processes of the aging body. There is also some evidence of low-dose lithium exerting a similar and sometimes synergistic effect on these systems. This review summarizes these findings with a focus on low-dose lithium's potential benefits on the aging process and age-related diseases of these systems, such as cardiovascular disease, osteoporosis, sarcopenia, obesity and type 2 diabetes, Alzheimer's disease, and the chronic low-grade inflammatory state known as inflammaging. Although lithium's actions have been widely studied in the brain, the study of the potential benefits of lithium, particularly at a low dose, is still relatively novel. Therefore, this review aims to provide possible mechanistic insights for future research in this field.


Asunto(s)
Trastorno Bipolar , Diabetes Mellitus Tipo 2 , Humanos , Litio/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Trastorno Bipolar/psicología , Encéfalo/metabolismo , Suplementos Dietéticos
10.
J Am Heart Assoc ; 11(21): e026619, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36285820

RESUMEN

Background Adverse childhood experiences (ACEs) have been linked to increased cardiovascular disease (CVD) risk. Previous reports have suggested that accelerated biological aging-indexed by telomere length (TL) and mitochondrial DNA copy number (mtDNAcn)-may contribute to associations between ACEs and cardiovascular health outcomes. Here, we examine the potential mediating effects of TL and mtDNAcn on the association between ACEs and central arterial stiffness-an intermediate cardiovascular health outcome-as a novel pathway linking ACEs to CVD risk among young adults. Methods and Results One hundred and eighty-five (n=102 women; mean age, 22.5±1.5 years) individuals provided information on ACEs. TL (kb per diploid cell) and mtDNAcn (copies per diploid cell) were quantified using quantitative polymerase chain reaction techniques. Central arterial stiffness was measured as carotid-femoral pulse wave velocity (cfPWV; m/s). Multiple linear regression analyses were used to examine the associations between ACEs, TL, mtDNAcn, and cfPWV. ACEs were positively associated with cfPWV (ß=0.147, P=0.035). TL (ß=-0.170, P=0.011) and mtDNAcn (ß=-0.159, P=0.019) were inversely associated with cfPWV. Neither TL (ß=-0.027, P=0.726) nor mtDNAcn (ß=0.038, P=0.620) was associated with ACEs. Neither marker mediated the association between ACEs and cfPWV. Conclusions An increasing number of ACEs were associated with a faster cfPWV and thus, a greater degree of central arterial stiffness. ACEs were not associated with either TL or mtDNAcn, suggesting that these markers do not represent a mediating pathway linking ACEs to central arterial stiffness.


Asunto(s)
Experiencias Adversas de la Infancia , Enfermedades Cardiovasculares , Rigidez Vascular , Adulto Joven , Humanos , Femenino , Adulto , ADN Mitocondrial/genética , Variaciones en el Número de Copia de ADN , Análisis de la Onda del Pulso , Biomarcadores/metabolismo , Telómero/genética , Telómero/metabolismo , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/genética
11.
Brain Behav Immun Health ; 25: 100516, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36177305

RESUMEN

Adverse childhood experiences (ACEs) are associated with dysregulation of inflammation and cortisol. The objectives of this study were to use principal component analysis to explore the inflammatory biomarker data to create inflammation composite variables; to examine the relationship between these composite measures of inflammation with ACEs and cortisol; and to assess whether these relationships were moderated by sex. The analysis included 232 young adults from the Niagara Longitudinal Heart Study (NLHS). After adjusting for covariates, higher exposure to ACEs significantly predicted higher low-grade inflammation. These results further support the use of multiple biomarkers to understand the complex relationships among ACEs, cortisol, and inflammation, which should be further examined in longitudinal studies to study biomarker trajectories.

12.
Exp Physiol ; 107(9): 1029-1036, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35912981

RESUMEN

NEW FINDINGS: What is the central question in this study? Promoting muscle health with regular aerobic exercise can improve mental health through a kynurenine metabolic pathway: do conditions of muscle disease such as muscular dystrophy negatively influence this pathway? What is the main finding and its importance? The DBA/2J mdx model of Duchenne muscular dystrophy exhibits altered kynurenine metabolism with less kynurenic acid and peroxisome proliferator-activated receptor-γ coactivator 1-α and higher levels of tumour necrosis factor α mRNA - results associated with anxiety-like behaviour. ABSTRACT: Regular exercise can direct muscle kynurenine (KYN) metabolism toward the neuroprotective branch of the kynurenine pathway thereby limiting the accumulation of neurotoxic metabolites in the brain and contributing to mental resilience. However, the effect of muscle disease on KYN metabolism has not yet been investigated. Previous work has highlighted anxiety-like behaviours in approximately 25% of patients with Duchenne muscular dystrophy (DMD), possibly due to altered KYN metabolism. Here, we characterized KYN metabolism in mdx mouse models of DMD. Young (8-10 week old) DBA/2J (D2) mdx mice, but not age-matched C57BL/10 (C57) mdx mice, had lower levels of circulating kynurenic acid (KYNA) and lower KYNA:KYN ratio compared with their respective wild-type (WT) controls. While both C57 and D2 mdx mice displayed signs of anxiety-like behaviour, spending more time in the corners of the arena during a novel object recognition test, this effect was more prominent in D2 mdx mice. Correlational analysis detected a significant negative association between KYNA:KYN levels and time spent in corners in D2 mice, but not C57 mice. In extensor digitorum longus muscles from D2 mdx mice, but not C57 mdx mice, we found lowered protein levels of peroxisome proliferator-activated receptor-γ coactivator 1-α and kynurenine amino transferase-1 enzyme when compared with WT. Furthermore, D2 mdx quadriceps muscles had the highest level of tumour necrosis factor α expression, which is suggestive of enhanced inflammation. Thus, our pilot work shows that KYN metabolism is altered in D2 mdx mice, with a potential contribution from altered muscle health.


Asunto(s)
Distrofia Muscular de Duchenne , Animales , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Ácido Quinurénico/metabolismo , Ácido Quinurénico/farmacología , Quinurenina/metabolismo , Quinurenina/farmacología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Endogámicos mdx , Músculo Esquelético/metabolismo , Distrofia Muscular de Duchenne/metabolismo , Receptores Activados del Proliferador del Peroxisoma/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
13.
BMC Public Health ; 22(1): 1598, 2022 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-35996138

RESUMEN

BACKGROUND: Youth voice has been largely absent from deliberations regarding public health measures intended to prevent SARS-CoV-2 transmission, despite being one of the populations most impacted by school-based policies. To inform public health strategies and messages, we examined the level of student support of mask use in public spaces and school mask requirements, as well as factors associated with students' perspectives. METHODS: We used cross-sectional survey data from 42,767 adolescents attending 133 Canadian secondary schools that participated in the COMPASS study during the 2020/2021 school year. Multinomial regression models assessed support for i) wearing a mask in indoor public spaces and ii) schools requiring students to wear masks, in association with COVID-19 knowledge, concerns, and perceived risk. RESULTS: Wearing masks in indoor public spaces was supported by 81.9% of students; 8.7% were unsupportive and 9.4% were neutral/undecided. School mask requirements were supported by 67.8%, with 23.1% neutral and 9.1% unsupportive. More females supported mask wearing in public spaces (83.9% vs. 79.1%) and school mask requirements (70.8% vs. 63.5%) than males. Students had increased odds of supporting mask use in public spaces and school mask requirements if they reported concerns about their own or their family's health, had discussions regarding ways to prevent infection, perceived COVID-19 to be a risk to young people, and knew that signs are not always present in COVID-19 cases and that masks prevent SARS-CoV-2 transmission if someone coughs. CONCLUSIONS: During the year following the beginning of the pandemic, most students supported the required use of masks in schools and wearing masks in indoor public spaces. Improving knowledge around the effectiveness of masks appears likely to have the largest impact on mask support in adolescent populations among the factors studied.


Asunto(s)
COVID-19 , Adolescente , COVID-19/epidemiología , COVID-19/prevención & control , Canadá/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Salud Pública , SARS-CoV-2 , Instituciones Académicas , Estudiantes
14.
Microbiol Spectr ; 10(4): e0177222, 2022 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-35862953

RESUMEN

Zika virus and dengue virus are evolutionarily related and structurally similar mosquito-borne Flaviviruses. These congruencies can lead to cross-reactive antibody binding, whereby antibodies generated from previous dengue virus immunity can augment Zika virus replication in vitro. This phenomenon, termed antibody-dependent enhancement, may participate in the clinical manifestations detected in areas with Flavivirus cocirculations where Zika virus is endemic; however, a causal relationship has yet to be determined. The KU812 mast cell/basophil line was integral in identifying the first Flavivirus infection in mast cells and serves as an effective in vitro model to study dengue virus antibody-dependent enhancement. Mast cells, sentinel white blood cells intrinsic in coordinating early immune defenses, are characteristically situated in the intradermal space and are therefore among the first immune cells interfaced with blood-feeding mosquitoes. Here, we tested whether KU812 cells were permissive to Zika virus, how previous dengue virus immunity might augment Zika virus infection, and whether either condition induces an immunological response. We report an antibody-dependent enhancement effect of Zika virus infection in KU812 cells across multiple time points (48, 72, and 96 hours postinfection [hpi]) and a range of multiplicities of infection (4.0 × 10-3 to 4) using various concentrations of cross-reactive dengue virus monoclonal antibodies (D11C and 1.6D). This antigen-specific antibody-mediated infection was selectively coupled to chemokine ligand 5 (CCL5), interleukin 1ß (IL-1ß), and C-X-C motif chemokine ligand 10 (CXCL10) secretion and a reduction in granzyme B (GrB) release. Therefore, mast cells and/or basophils may significantly augment Zika virus infection in the context of preexisting dengue virus immunity. IMPORTANCE Antibodies generated against one dengue serotype can enhance infection of another by a phenomenon called antibody-dependent enhancement (ADE). Additionally, antigenic similarities between Zika and dengue viruses can promote Zika virus infection by way of ADE in vitro using these very same anti-dengue antibodies. We used the KU812 cell line to demonstrate for the first time that anti-dengue antibodies enhanced infectious Zika virus replication in a mast cell model and specifically increased CCL5, CXCL10, and IL-1ß, while also impairing granzyme B secretion. Furthermore, enhanced Zika virus infection and selective mediator release were mechanistically dependent on fragment crystallizable gamma receptor II (FcγRII). These findings establish a new model for Zika virus research and a new subcategory of immune cells previously unexplored in the context of Zika virus enhancement while being some of the very first immune cells likely to meet a blood-feeding infected mosquito.


Asunto(s)
Virus del Dengue , Infección por el Virus Zika , Virus Zika , Animales , Anticuerpos Antivirales , Acrecentamiento Dependiente de Anticuerpo , Quimiocinas , Reacciones Cruzadas , Virus del Dengue/fisiología , Granzimas , Humanos , Ligandos , Mastocitos , Replicación Viral
15.
Am J Physiol Cell Physiol ; 322(4): C614-C623, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35196169

RESUMEN

Neurodegenerative diseases such as Alzheimer's disease (AD) are becoming more prevalent in our aging society. One specific neuropathological hallmark of this disease is the accumulation of amyloid-ß (Aß) peptides, which aggregate to form extraneuronal plaques. Increased Aß peptides are often observed well before symptoms of AD develop, highlighting the importance of targeting Aß-producing pathways early on in disease progression. Evidence indicates that exercise has the capacity to reduce Aß peptide production in the brain; however, the mechanisms remain unknown. Exercise-induced signaling mediators could be the driving force behind some of the beneficial effects observed in the brain with exercise. The purpose of this study was to examine if postexercise serum and the factors it contains can alter neuronal amyloid precursor protein (APP) processing. Human SH-SY5Y neuronal cells were differentiated with retinoic acid for 5 days and treated with 10% pre- or postexercise serum from humans for 30 min. Cells were collected for analysis of acute (30 min; n = 6) or adaptive (24 h posttreatment; n = 6) responses. There were no statistical differences in a disintegrin and metalloproteinase 10 (ADAM10) and ß-site amyloid precursor protein cleaving enzyme 1 (BACE1) mRNA or protein expression with postexercise serum treatment at either time point. However, there was an increase in the ratio of soluble amyloid precursor protein α (sAPPα) to soluble amyloid precursor protein ß (sAPPß) protein content (P = 0.05) after 30 min of postexercise serum treatment. In addition, 30 min of postexercise serum treatment increased ADAM10 (P = 0.01) and BACE1 (P = 0.02) activity. These findings suggest that postexercise serum modulates important enzymes involved in APP processing, potentially pushing the cascade toward the nonamyloidogenic arm.


Asunto(s)
Enfermedad de Alzheimer , Precursor de Proteína beta-Amiloide , Enfermedad de Alzheimer/genética , Secretasas de la Proteína Precursora del Amiloide/genética , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Péptidos beta-Amiloides , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Ácido Aspártico Endopeptidasas/genética , Ácido Aspártico Endopeptidasas/metabolismo , Humanos
16.
J Pers Med ; 12(1)2022 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-35055349

RESUMEN

The "best of both worlds" is not often the case when it comes to implementing new health models, particularly in community settings. It is often a struggle between choosing or balancing between two components: depth of research or financial profit. This has become even more apparent with the recent shift to move away from a traditionally reactive model of medicine toward a predictive/preventative one. This has given rise to many new concepts and approaches with a variety of often overlapping aims. The purpose of this perspective is to highlight the pros and cons of the numerous ventures already implementing new concepts, to varying degrees, in community settings of quite differing scales-some successful and some falling short. Scientific wellness is a complex, multifaceted concept that requires integrated experimental/analytical designs that demand both high-quality research/healthcare and significant funding. We currently see the more likely long-term success of those ventures in which any profit is largely reinvested into research efforts and health/healthspan is the primary focus.

17.
Front Physiol ; 13: 1061715, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36685192

RESUMEN

Introduction: It is well established that sclerostin antagonizes the anabolic Wnt signalling pathway in bone, however, its physiological role in other tissues remains less clear. This study examined the effect of a high-fat diet (HFD) on sclerostin content and downstream markers of the Wnt signaling pathway (GSK3ß and ß-catenin) within subcutaneous inguinal white adipose tissue (iWAT), and visceral epididymal WAT (eWAT) depots at rest and in response to acute aerobic exercise. Methods: Male C57BL/6 mice (n = 40, 18 weeks of age) underwent 10 weeks of either a low-fat diet (LFD) or HFD. Within each diet group, mice were assigned to either remain sedentary (SED) or perform 2 h of endurance treadmill exercise at 15 m min-1 with 5° incline (EX), creating four groups: LFD + SED (N = 10), LFD + EX (N = 10), HFD + SED (N = 10), and HFD + EX (N = 10). Serum and WAT depots were collected 2 h post-exercise. Results: Serum sclerostin showed a diet-by-exercise interaction, reflecting HFD + EX mice having higher concentration than HFD + SED (+31%, p = 0.03), and LFD mice being unresponsive to exercise. iWAT sclerostin content decreased post-exercise in both 28 kDa (-31%, p = 0.04) and 30 kDa bands (-36%, main effect for exercise, p = 0.02). iWAT ß-catenin (+44%, p = 0.03) and GSK3ß content were higher in HFD mice compared to LFD (+128%, main effect for diet, p = 0.005). Monomeric sclerostin content was abolished in eWAT of HFD mice (-96%, main effect for diet, p < 0.0001), was only detectable as a 30 kDa band in LFD mice and was unresponsive to exercise. ß-catenin and GSK3ß were both unresponsive to diet and exercise within eWAT. Conclusion: These results characterized sclerostin's content to WAT depots in response to acute exercise, which appears to be specific to a reduction in iWAT and identified a differential regulation of sclerostin's form/post-translational modifications depending on diet and WAT depot.

18.
Brain Behav Immun Health ; 13: 100211, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34589737

RESUMEN

Previous research has demonstrated that perfectionism is implicated in poorer health and earlier mortality. However, to our knowledge, research has not yet determined how individual differences in perfectionistic cognitions are related to intermediary health markers such as inflammation. Thus, within the theoretical frameworks of the perfectionism diathesis-stress model (Hewitt and Flett, 1993) and the cognitive theory of perfectionism (Flett et al., 2018; Flett et al., 2016) the aims of our study were to test whether individual differences in perfectionistic cognitions were associated with low-grade inflammation via c-reactive CRP and IL-6 biomarkers and whether these relationships varied as a function perceived stress. The sample included 248 Canadian young adults (52% female, Mage â€‹= â€‹22.89, SD â€‹= â€‹1.53) who completed surveys assessing key constructs such as perfectionistic cognitions and perceived stress along with providing assessments of body fat percentage and serum samples of IL-6 and CRP. Regression analyses indicated that perfectionistic cognitions were not related to IL-6 under any conditions of stress. However, under high levels of stress perfectionistic cognitions were associated with elevated levels of CRP and these findings held after accounting for the effects of smoking status, body fat percentage, and respondent sex. The present work adds to the growing body of evidence supporting links between personality and inflammation. These findings raise the possibility that experiencing more frequent thoughts centered on the need to be perfect when coupled with higher levels of stress may set the stage for greater vulnerability for chronic inflammation.

19.
Chem Sci ; 12(6): 2133-2137, 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-34163977

RESUMEN

Herein, we describe an isothermal proximity CRISPR Cas12a assay that harnesses the target-induced indiscrimitive single-stranded DNase activity of Cas12a for the quantitative profiling of gene expression at the mRNA level and detection of proteins with high sensitivity and specificity. The target recognition is achieved through proximity binding rather than recognition by CRISPR RNA (crRNA), which allows for flexible assay design. A binding-induced primer extension reaction is used to generate a predesigned CRISPR-targetable sequence as a barcode for further signal amplification. Through this dual amplification protocol, we were able to detect as low as 1 fM target nucleic acid and 100 fM target protein isothermally. The practical applicability of this assay was successfully demonstrated for the temporal profiling of interleukin-6 gene expression during allergen-mediated mast cell activation.

20.
Physiol Rep ; 9(11): e14920, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34110720

RESUMEN

Central arterial stiffness is an independent predictor of cardiovascular disease. It is characterized by a marked reduction in the elastin-collagen ratio of the arterial wall extracellular matrix (ECM), and is largely the result of degradation of various ECM components. Matrix metalloproteinase-3 (MMP-3) may contribute to central arterial stiffness via its involvement in ECM homeostasis and remodeling. This study examined the association between serum MMP-3 concentrations and central arterial stiffness and potential interactions of MMP-3 and traditional cardiovascular risk factors in a population of healthy young adults. A total of 206 participants (n = 109 females) aged 19-25 years were included in the current study. Central arterial stiffness was measured non-invasively as carotid-femoral pulse wave velocity (cfPWV) (m/s). MMP-3 concentrations (ng/ml) were measured using ELISA techniques. Regression analyses were used to examine the association between cfPWV and MMP-3, adjusting for age, sex, smoking status, body mass index (BMI), instantaneous mean arterial pressure (MAP) and heart rate, and serum C-reactive protein. Interactions between MMP-3 with smoking, BMI, sex, and MAP were analyzed in subsequent regression models. MMP-3 was an independent predictor of cfPWV (ß = 0.187, p = 0.007), and significant interactions between MMP-3 and regular smoking (ß = 0.291, p = 0.022), and MMP-3 and BMI (ß = 0.210, p = 0.013) were observed. Higher serum MMP-3 concentrations were associated with a faster cfPWV and thus, greater central arterial stiffness. Interactions between MMP-3 and smoking, and MMP-3 and BMI may, in part, drive the association between MMP-3 and central arterial stiffness.


Asunto(s)
Índice de Masa Corporal , Metaloproteinasa 3 de la Matriz/sangre , Fumar/efectos adversos , Rigidez Vascular , Adulto , Presión Sanguínea , Proteína C-Reactiva/análisis , Femenino , Factores de Riesgo de Enfermedad Cardiaca , Frecuencia Cardíaca , Humanos , Masculino , Rigidez Vascular/fisiología , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...