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1.
Pers Soc Psychol Rev ; 27(3): 309-331, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36461780

RESUMO

ACADEMIC ABSTRACT: In the present review, we propose a theory that seeks to recontextualize various existing theories as functions of people's perceptions of their consistency with those around them. This theory posits that people seek social consistency for both epistemic and relational needs and that social inconsistency is both negative and aversive, similar to the experience of cognitive dissonance. We further posit that the aversive nature of perceiving social inconsistency leads people to engage in various behaviors to mitigate or avoid these inconsistencies. When these behaviors fail, however, people experience chronic social inconsistency, which, much like chronic rejection, is associated with physical and mental health and well-being outcomes. Finally, we describe how mitigation and avoidance of social inconsistency underlie many seemingly unrelated theories, and we provide directions for how future research may expand on this theory. PUBLIC ABSTRACT: In the present review, we propose that people find inconsistency with those around them to be an unpleasant experience, as it threatens people's core need to belong. Because the threat of reduced belongingness evokes negative feelings, people are motivated to avoid inconsistency with others and to mitigate the negative feelings that are produced when it inevitably does arise. We outline several types of behaviors that can be implemented to avoid or mitigate these inconsistencies (e.g., validation, affirmation, distancing, etc.). When these behaviors cannot be implemented successfully, people experience chronic invalidation, which is associated with reduced physical and mental health and well-being outcomes. We discuss how invalidation may disproportionately affect individuals with minoritized identities. Furthermore, we discuss how belongingness could play a key role in radicalization into extremist groups.


Assuntos
Afeto , Dissonância Cognitiva , Humanos , Emoções , Exame Físico , Pesquisa Qualitativa
2.
J Med Internet Res ; 23(10): e30491, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34665141

RESUMO

BACKGROUND: The COVID-19 pandemic has increased the demand for youth mental health services in Canada as disruptions to clinical care continue to persist due to the risk of transmission and exposure to the virus. Digital mental health interventions, including web-based resources and mobile apps, have provided opportunities to support youth mental health remotely across Canada. There is a need to better understand how these digital interventions are being selected, recommended, and used in various regions across Canada. OBJECTIVE: A national jurisdictional scan was completed to (1) determine what web-based programs, apps, and websites are promoted and licensed in Canada for youth mental health; (2) identify criteria and decision-making processes that Canadian jurisdictions use to select web-based programs, apps, and websites for youth mental health; and (3) identify upcoming trends, innovations, and digital mental health possibilities that are emerging in the youth sector. METHODS: The aims of the jurisdictional scan were addressed through a review of related academic and grey literature; stakeholder interviews, including individuals involved in various areas of the youth mental health sector; and a social media review of pertinent Twitter content. RESULTS: A total of 66 web-based resources and apps were identified for use by youth in Canada. 16 stakeholder interviews were completed and included discussions with researchers, clinicians, youth organizations, and others involved in digital interventions for youth mental health. These discussions identified a limited use of frameworks used to guide decision-making processes when selecting digital interventions. Many clinicians agreed on a similar set of eligibility requirements for youth mental health apps and digital resources, such as the evidence base and cultural relevance of the intervention. Stakeholders also identified upcoming trends and innovations in the youth digital mental health space, including artificial intelligence, digital phenotyping, and personalized therapy. Over 4 weeks, 2184 tweets were reviewed to identify and compare global and national trends and innovations involving digital mental health and youth. Key trends included the promotion of regional chat services as well as the effects of the COVID-19 pandemic on youth mental health and access to care. CONCLUSIONS: As organizations begin to plan for the delivery of mental health care following the pandemic, there are concerns about the sustainability of these digital mental health interventions as well as a need for services to be more informed by the experiences and preferences of youth.


Assuntos
COVID-19 , Saúde Mental , Adolescente , Inteligência Artificial , Canadá , Tomada de Decisão Clínica , Humanos , Pandemias , SARS-CoV-2
3.
Adapt Phys Activ Q ; 36(3): 339-358, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31155920

RESUMO

Identifying as a regular exerciser has been found to effectively alter stereotypes related to warmth and competence for adults with a physical disability; however, it remains unclear how sport participation can influence this trend. Therefore, this study aimed to examine warmth and competence perceptions of adults with a physical disability portrayed as elite and nonelite athletes relative to other athletic and nonathletic subgroups of adults with and without a physical disability in the context of the stereotype content model. Using survey data from able-bodied participants (N = 302), cluster analyses were applied to a behaviors from intergroup affect and stereotypes map for displaying the intersection of warmth and competence perceptions. The results demonstrated that adults with a physical disability who are described as elite athletes (i.e., Paralympians) are clustered with high warmth and high competence, similar to their able-bodied athletic counterparts (i.e., Olympians). The findings suggest that perceiving athletic and elite sport statuses for adults with a physical disability may counter the stereotypes commonly applied to this group.


Assuntos
Atletas , Pessoas com Deficiência , Estereotipagem , Adolescente , Adulto , Idoso , Análise por Conglomerados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
4.
Int J Mol Sci ; 18(5)2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28468326

RESUMO

Adipose tissue plays a key role in the development of type-2 diabetes via the secretion of adipokines. The current study investigated if secretion media derived from intact visceral (VAT) and subcutaneous (SAT) adipose tissues from extremely obese men and women differently suppressed insulin signaling in human skeletal myotubes derived from a healthy, non-diabetic male and female donor, respectively. Adipose tissue samples were collected from men and women during laparoscopic bariatric surgery. In general, secretion media collected from both SAT and VAT depots caused impaired insulin signaling in myotubes, independent of sex. In females, this was true regardless of the protein kinase B (Akt) phosphorylation site (Akt Thr308 and Akt Ser473) assessed (p < 0.01). In males, both SAT and VAT secretion media reduced Akt Thr308 activation in insulin-stimulated myotubes compared to controls (p < 0.001); however, only the VAT secretion media impaired Akt Ser473 phosphorylation. Independent of sex, 13 out of 18 detected cytokines, chemokines, and growth factors were more abundant in VAT versus SAT secretion media (p < 0.01). Both SAT and VAT secretion media from obese men and women acutely suppress insulin signaling in myotubes, despite different secretion profiles. We propose that this crosstalk model will help to extend our understanding of the interplay between adipose and muscle, as well as the pathogenesis of type-2 diabetes.


Assuntos
Adipocinas/metabolismo , Insulina/metabolismo , Gordura Intra-Abdominal/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Obesidade Mórbida/metabolismo , Transdução de Sinais , Gordura Subcutânea/metabolismo , Adulto , Células Cultivadas , Quimiocinas/metabolismo , Meios de Cultivo Condicionados/farmacologia , Feminino , Humanos , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fatores Sexuais
5.
AIDS Behav ; 20 Suppl 1: S185-96, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26377328

RESUMO

Attachment anxiety is negatively associated with condom use; however, little research has assessed mechanisms underlying this relationship. In two studies we assessed the relationships among attachment orientations, perceived partner rejection, and condom use. In Study 1 we used a survey methodology and found that a measure of perceived partner rejection mediated the relationship between attachment anxiety and reported condom use behavior. In Study 2, women responded to condom use scenarios in which rejection was manipulated. We found a three-way interaction among attachment anxiety, attachment avoidance, and condom use intentions, such that perceived rejection from a potential sexual partner was associated with greater intentions to engage in unprotected sexual intercourse among women high in attachment anxiety and low in attachment avoidance, and among those high in attachment avoidance and low in attachment anxiety.


Assuntos
Ansiedade , Preservativos/estatística & dados numéricos , Individualidade , Apego ao Objeto , Assunção de Riscos , Parceiros Sexuais/psicologia , Adolescente , Adulto , Feminino , Infecções por HIV , Heterossexualidade , Humanos , Comportamento Sexual/psicologia , Inquéritos e Questionários
6.
Lipids Health Dis ; 14: 119, 2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26415741

RESUMO

BACKGROUND: We recently demonstrated that feeding a natural CLAt10,c12-enriched butter to lean female rats resulted in small, but significant increases in fasting glucose and insulin concentrations, and impaired insulin tolerance. Our goal was to extend these findings by utilizing the diabetes-prone female fatty Zucker rat. Rats were fed custom diets containing 45 % kcal of fat derived from control and CLAt10,c12-enriched butter for 8 weeks. METHODS: CLA t10,c12-enriched butter was prepared from milk collected from cows fed a high fermentable carbohydrate diet to create subacute rumen acidosis (SARA); control (non-SARA) butter was collected from cows fed a low grain diet. Female fatty Zucker rats (10 weeks old) were randomly assigned to one of four diet treatments: i) low fat (10 % kcal), ii) 45 % kcal lard, iii) 45 % kcal SARA butter, or iv) 45 % kcal non-SARA butter. A low fat fed lean Zucker group was used as a control group. After 8 weeks, i) glucose and insulin tolerance tests, ii) insulin signaling in muscle, adipose and liver, and iii) metabolic caging measurements were performed. RESULTS: Glucose and insulin tolerance were significantly impaired in all fatty Zucker groups, but to the greatest extent in the LARD and SARA conditions. Insulin signaling (AKT phosphorylation) was impaired in muscle, visceral (perigonadal) adipose tissue and liver in fatty Zucker rats, but was generally similar across dietary groups. Physical activity, oxygen consumption, food intake and weight gain were also similar amongst the various fatty Zucker groups. CONCLUSIONS: Increasing the consumption of a food naturally enriched with CLAt10,c12 significantly worsens glucose and insulin tolerance in a diabetes-prone rodent model. This outcome is not explained by changes in tissue insulin signaling, physical activity, energy expenditure, food intake or body mass.


Assuntos
Glicemia/metabolismo , Dieta Hiperlipídica/efeitos adversos , Resistência à Insulina , Ácidos Linoleicos Conjugados/efeitos adversos , Obesidade/metabolismo , Animais , Manteiga/efeitos adversos , Ingestão de Alimentos/fisiologia , Feminino , Teste de Tolerância a Glucose , Insulina/metabolismo , Gordura Intra-Abdominal/efeitos dos fármacos , Gordura Intra-Abdominal/metabolismo , Ácidos Linoleicos Conjugados/administração & dosagem , Fígado/efeitos dos fármacos , Fígado/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Obesidade/etiologia , Consumo de Oxigênio/fisiologia , Ratos , Ratos Zucker , Aumento de Peso/fisiologia
7.
J Physiol ; 592(12): 2653-65, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24687585

RESUMO

Adiponectin (Ad) has been proposed to be a regulator of mitochondrial biogenesis in skeletal muscle, and necessary for exercise-induced increases in mitochondrial content. We first confirmed that Ad could acutely increase the expression of mitochondrial proteins during a 10 h incubation in isolated soleus and extensor digitorum longus (EDL) muscles. Next, we further examined the role of Ad as a regulator of mitochondrial content using Ad knockout (AdKO) mice. The AdKO animals showed no differences in resting VO2, respiratory exchange ratio, or in time to exhaustion during exercise when compared to wild-type (WT) mice. There was a reduction in resting palmitate oxidation in isolated soleus from AdKO animals (-23%, P < 0.05) but not EDL, and 5-aminoimidazole-4-carboxamide (AICAR)-stimulated palmitate oxidation was similar in both genotypes regardless of muscle. There were no differences in protein markers of mitochondrial content (COX4, CORE1, CS, PDHE1α) in red and white gastrocnemius between WT and AdKO animals. A single bout of treadmill running increased the phosphorylation of AMP-activated protein kinase (AMPK) and the mRNA expression of mitochondrial proteins in red and white gastrocnemius in both WT and AdKO animals, with no differences between genotypes. Finally, 8 weeks of chronic exercise training increased the protein content of mitochondrial markers similarly (∼25-35%) in red gastrocnemius from both WT and AdKO mice. Collectively, our results demonstrate that the absence of Ad is not accompanied by reductions in mitochondrial protein content, or a reduction in aerobic exercise capacity. We conclude that Ad is not required for the maintenance of mitochondrial content, or for exercise-induced increases in skeletal muscle mitochondrial proteins.


Assuntos
Adiponectina/fisiologia , Proteínas Mitocondriais/metabolismo , Músculo Esquelético/fisiologia , Corrida/fisiologia , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
8.
Lipids Health Dis ; 13: 101, 2014 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-24956949

RESUMO

BACKGROUND: Numerous studies have investigated the effects of isolated CLA supplementation on glucose homeostasis in humans and rodents. However, both the amount and relative abundance of CLA isomers in supplemental form are not representative of what is consumed from natural sources. No study to date has examined the effects of altered CLA isomer content within a natural food source. Our goal was to increase the content of the insulin desensitizing CLAt10,c12 isomer relative to the CLAc9,t11 isomer in cow's milk by inducing subacute rumenal acidosis (SARA), and subsequently investigate the effects of this milk fat on parameters related to glucose and insulin tolerance in rats. METHODS: We fed female rats (~2.5 to 3 months of age) CLA t10,c12 -enriched (SARA) butter or non-SARA butter based diets for 4 weeks in either low (10% of kcal from fat; 0.18% total CLA by weight) or high (60% of kcal from fat; 0.55% total CLA by weight) amounts. In an effort to extend these findings, we then fed rats high (60% kcal) amounts of SARA or non-SARA butter for a longer duration (8 weeks) and assessed changes in whole body glucose, insulin and pyruvate tolerance in comparison to low fat and 60% lard conditions. RESULTS: There was a main effect for increased fasting blood glucose and insulin in SARA vs. non-SARA butter groups after 4 weeks of feeding (p < 0.05). However, blood glucose and insulin concentration, and maximal insulin-stimulated glucose uptake in skeletal muscle were similar in all groups. Following 8 weeks of feeding, insulin tolerance was impaired by the SARA butter, but not glucose or pyruvate tolerance. The non-SARA butter did not impair tolerance to glucose, insulin or pyruvate. CONCLUSIONS: This study suggests that increasing the consumption of a naturally enriched CLAt10,c12 source, at least in rats, has minimal impact on whole body glucose tolerance or muscle specific insulin response.


Assuntos
Manteiga/efeitos adversos , Insulina/farmacologia , Ácidos Linoleicos Conjugados/sangue , Animais , Glicemia/efeitos dos fármacos , Feminino , Músculo Esquelético/efeitos dos fármacos , Ratos
9.
Arch Environ Contam Toxicol ; 67(3): 310-34, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24699838

RESUMO

As part of a broader study of budgets, transport, and bioaccumulation of persistent organic contaminants in the Strait of Georgia, Canada, matching samples of sediment and bulk benthos were collected near two marine sewage outfalls, two large urban harbours, and background areas. Samples were analyzed for polychlorinated biphenyl (PCB) and polybrominated diphenyl ether (PBDE) congeners. We present data for those congeners that fell within the top six rankings by concentration (23 PCBs and 10 PBDEs) within at least one of the environmental media measured in other studies (air, water, sediments, benthos, pelagic biota). Multifactor regression analyses incorporating sediment characteristics (total organic carbon, fines) predicted uptake (r (2) = 0.74 to 0.98, p < 0.04) over the range of congeners and habitats examined. PBDEs were taken up by biota more readily than PCBs, suggesting a large, potentially available biological reservoir of PBDEs in sediments. Dominant congeners in benthos comprised PBDEs 47, 99, 209, and 100 and PCBs 138/163, 153, 101, 118, and 110. PBDE uptake was anomalously high near one wastewater outfall, likely due to selective feeding on PBDE-enriched particulates from that source. Conversely, outfalls supply food and sediments with PCB concentrations similar to ambient sediments. However, organic enrichment of sediments near outfalls clearly enhanced PCB uptake by benthos, probably due to greatly increased biomass turnover near these sources. Data suggest there to be an initial reservoir of PCBs in newly settled juvenile benthos, which is much less evident for PBDEs. This is likely a consequence of the ecosystem-wide distribution of legacy PCBs but not the more current-use PBDEs. Congener-uptake patterns were dependent on source and input dynamics, feeding methods, and contaminant metabolism or debromination, particularly of deca-BDE.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Éteres Difenil Halogenados/metabolismo , Invertebrados/metabolismo , Bifenilos Policlorados/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Canadá , Éteres Difenil Halogenados/análise , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise
10.
bioRxiv ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38915698

RESUMO

Renalase (Rnls), annotated as an oxidase enzyme, is a GWAS gene associated with Type 1 Diabetes (T1D) risk. We previously discovered that Rnls inhibition delays diabetes onset in mouse models of T1D in vivo , and protects pancreatic ß cells against autoimmune killing, ER and oxidative stress in vitro . The molecular biochemistry and functions of Rnls are entirely uncharted. Here we find that Rnls inhibition defends against loss of ß cell mass and islet dysfunction in chronically stressed Akita mice in vivo . We used RNA sequencing, untargeted and targeted metabolomics and metabolic function experiments in mouse and human ß cells and discovered a robust and conserved metabolic shift towards glycolysis, amino acid abundance and GSH synthesis to counter protein misfolding stress, in vitro . Our work illustrates a function for Rnls in mammalian cells, and suggests an axis by which manipulating intrinsic properties of ß cells can rewire metabolism to protect against diabetogenic stress.

11.
Artigo em Inglês | MEDLINE | ID: mdl-38613562

RESUMO

PURPOSE: Using diagnostic computed tomography (dCT) scans instead of CT simulation (CTsim) scans can increase departmental efficiency and reduce patient burden. The goal of the DART trial was to assess the efficacy and acceptability of dCT-based planning workflows with a focus on patient experiences, plan deliverability and adequacy of target coverage, and workflows. METHODS AND MATERIALS: Patients undergoing same-day CTsim and treatment for palliative radiation therapy to thoracic, abdominopelvic, or proximal limb targets with a recent dCT (within 28 days) in a reproducible position were eligible. After stratifying by target type (bone or soft tissue vs. visceral), participants were randomized (1:2 ratio) between CTsim-based (CTsim arm) vs. dCT-based planning (dCT arm). The primary endpoint was time in center (TIC), defined as total time spent in the cancer center on first day of treatment, from first radiation department appointment to first fraction completion. Secondary endpoints included plan deliverability, adequacy of target coverage, and stakeholder acceptability. RESULTS: Thirty-three patients (42 treatment sites) were enrolled between June 2022 and April 2023. The median age was 72 (interquartile range [IQR]: 67-78), 73% were male, and the most common primary cancers were lung (33%), prostate (24%), and breast (12%). The most common dose and fractionations were 8 Gy in 1 and 20 Gy in 5 fractions (50% and 43% of plans, respectively). TIC was 4.7 ± 1.1 hours (mean ± SD) in the CTsim arm vs. 0.41 ± 0.14 hours in the dCT arm (P < .001). All dCT plans were deliverable. All plans in both arms were rated as "acceptable" (80% CTsim; 81% dCT) or "acceptable with minor deviation" (20% CTsim; 19% dCT). Patient perception of acceptability was similar in both arms with the exception of time burden, which was rated as "acceptable" by 50% in the CTsim arm vs. 90% in the dCT arm (P = .025). CONCLUSION: dCT-based radiation planning substantially reduced TIC without detriment in plan deliverability or quality and had a tangible impact on patient experience with reduced patient-reported time burden.

12.
Endocrinology ; 165(1)2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37947352

RESUMO

Canonically, type 1 diabetes (T1D) is a disease characterized by autoreactive T cells as perpetrators of endocrine dysfunction and ß cell death in the spiral toward loss of ß cell mass, hyperglycemia, and insulin dependence. ß Cells have mostly been considered as bystanders in a flurry of autoimmune processes. More recently, our framework for understanding and investigating T1D has evolved. It appears increasingly likely that intracellular ß cell stress is an important component of T1D etiology/pathology that perpetuates autoimmunity during the progression to T1D. Here we discuss the emerging and complex role of ß cell stress in initiating, provoking, and catalyzing T1D. We outline the bridges between hyperglycemia, endoplasmic reticulum stress, oxidative stress, and autoimmunity from the viewpoint of intrinsic ß cell (dys)function, and we extend this discussion to the potential role for a therapeutic ß cell stress-metabolism axis in T1D. Lastly, we mention research angles that may be pursued to improve ß cell endocrine function during T1D. Biology gleaned from studying T1D will certainly overlap to innovate therapeutic strategies for T2D, and also enhance the pursuit of creating optimized stem cell-derived ß cells as endocrine therapy.


Assuntos
Diabetes Mellitus Tipo 1 , Hiperglicemia , Células Secretoras de Insulina , Humanos , Diabetes Mellitus Tipo 1/metabolismo , Células Secretoras de Insulina/metabolismo , Estresse do Retículo Endoplasmático , Hiperglicemia/metabolismo , Autoimunidade
13.
Diabetes ; 72(8): 1127-1143, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37216639

RESUMO

Type 1 diabetes (T1D) is caused by the immune-mediated loss of pancreatic ß-cells that produce insulin. The latest advances in stem cell (SC) ß-cell differentiation methods have made a cell replacement therapy for T1D feasible. However, recurring autoimmunity would rapidly destroy transplanted SC ß-cells. A promising strategy to overcome immune rejection is to genetically engineer SC ß-cells. We previously identified Renalase (Rnls) as a novel target for ß-cell protection. Here we show that Rnls deletion endows ß-cells with the capacity to modulate the metabolism and function of immune cells within the local graft microenvironment. We used flow cytometry and single-cell RNA sequencing to characterize ß-cell graft-infiltrating immune cells in a mouse model for T1D. Loss of Rnls within transplanted ß-cells affected both the composition and the transcriptional profile of infiltrating immune cells in favor of an anti-inflammatory profile with decreased antigen-presenting capacity. We propose that changes in ß-cell metabolism mediate local immune regulation and that this feature could be exploited for therapeutic goals. ARTICLE HIGHLIGHTS: Protective Renalase (Rnls) deficiency impacts ß-cell metabolism. Rnls-deficient ß-cell grafts do not exclude immune infiltration. Rnls deficiency in transplanted ß-cells broadly modifies local immune function. Immune cell in Rnls mutant ß-cell grafts adopt a noninflammatory phenotype.


Assuntos
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Camundongos , Animais , Diabetes Mellitus Tipo 1/metabolismo , Células Secretoras de Insulina/metabolismo , Monoaminoxidase/genética , Monoaminoxidase/metabolismo , Antígenos
14.
Am J Physiol Regul Integr Comp Physiol ; 303(10): R1062-70, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23054173

RESUMO

High-fat (HF) diets impair skeletal muscle response to the insulin-sensitizing adipokine adiponectin (Ad) in rodents, preceding the development of insulin resistance. Skeletal muscle insulin response in HF-fed rats can be restored with chronic exercise; whether recovery of skeletal muscle Ad response is necessary for the exercise-induced recovery of insulin-stimulated glucose transport is not known. In the current study, insulin and Ad resistance were induced in rodents with 4 wk of HF feeding (HF(4); low-fat fed animals used as control). Rats were then treadmill-exercised (HF(5)EX(1), HF(6)EX(2)) or supplemented orally with the pharmacological agent ß-guadinoproprionic acid (GPA; HF(5)GPA(1), HF(6)GPA(2)) for 1 or 2 wk with continued HF feeding. Insulin and Ad responses (glucose transport and palmitate oxidation, respectively) were assessed 48 h after the last exercise bout ex vivo in isolated solei. Insulin response was impaired following 4 wk of HF feeding and improved with 1 and 2 wk of exercise and ß-GPA supplementation (HF(5)EX(1), HF(6)EX(2), HF(5)GPA(1), and HF(6)GPA(2)). The recovery of insulin response generally coincided with improved Akt Thr(308) phosphorylation in HF(5)GPA(1), HF(6)EX(2), and HF(6)GPA(2), although not in HF(5)EX(1). Ad-stimulated palmitate oxidation was not restored with either treatment. Total protein contents of AdipoR1, AdipoR2, APPL1, and APPL2, as well as total and phosphorylated AMPK and ACC were unaltered by diet, exercise, and ß-GPA at the assessed time points. We conclude that the exercise and pharmacologically (ß-GPA)-induced recovery of skeletal muscle insulin response after HF feeding is not dependent on the restoration of Ad response, as assessed ex vivo.


Assuntos
Adiponectina/metabolismo , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/farmacologia , Insulina/metabolismo , Músculo Esquelético/metabolismo , Condicionamento Físico Animal , Animais , Glicemia/fisiologia , Western Blotting , Feminino , Regulação da Expressão Gênica , Glicogênio/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
15.
Diabetes ; 71(5): 881-893, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35108373

RESUMO

Chronic hyperglycemia is associated with low response to aerobic exercise training in rodent models and humans, including reduced aerobic exercise capacity and impaired oxidative remodeling in skeletal muscle. Here, we investigated whether glucose lowering with the sodium-glucose cotransporter 2 inhibitor (SGLT2i), canagliflozin (Cana; 30 mg/kg/day), could restore exercise training response in a model of hyperglycemia (low-dose streptozotocin [STZ]). Cana effectively prevented increased blood glucose in STZ-treated mice. After 6 weeks of voluntary wheel running, Cana-treated mice displayed improvements in aerobic exercise capacity, higher capillary density in striated muscle, and a more oxidative fiber-type in skeletal muscle. In contrast, these responses were blunted or absent in STZ-treated mice. Recent work implicates glucose-induced accumulation of skeletal muscle extracellular matrix (ECM) and hyperactivation of c-Jun N-terminal kinase (JNK)/SMAD2 mechanical signaling as potential mechanisms underlying poor exercise response. In line with this, muscle ECM accretion was prevented by Cana in STZ-treated mice. JNK/SMAD2 signaling with acute exercise was twofold higher in STZ compared with control but was normalized by Cana. In human participants, ECM accumulation was associated with increased JNK signaling, low VO2peak, and impaired metabolic health (oral glucose tolerance test-derived insulin sensitivity). These data demonstrate that hyperglycemia-associated impairments in exercise adaptation can be ameliorated by cotherapy with SGLT2i.


Assuntos
Hiperglicemia , Inibidores do Transportador 2 de Sódio-Glicose , Animais , Canagliflozina/farmacologia , Canagliflozina/uso terapêutico , Matriz Extracelular/metabolismo , Glucose/metabolismo , Humanos , Hiperglicemia/tratamento farmacológico , Hiperglicemia/prevenção & controle , Camundongos , Atividade Motora , Músculo Esquelético/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Estreptozocina
16.
J Pers ; 78(4): 1271-99, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20545823

RESUMO

We hypothesized that the effect of initiator status on post breakup distress would vary as a function of trait self-esteem, such that individuals with low self-esteem would experience more distress after being rejected by their partners, whereas, among individuals with high self-esteem, initiator status would not predict distress. We used a prospective design in which university students (N=66) were assessed for emotional responses following the dissolution of their real-life romantic relationships, as well as a laboratory design in which students (N=190) imagined breaking up with their partners. As predicted, participants with lower trait self-esteem exhibited greater distress after experiencing or imagining a romantic rejection than after ending or imagining themselves ending their relationships. Conversely, distress experienced by those with high trait self-esteem did not differ as a function of who ended the relationship. Implications for understanding self-esteem processes and the effects of romantic rejection are discussed.


Assuntos
Adaptação Psicológica , Caráter , Corte , Amor , Apego ao Objeto , Rejeição em Psicologia , Autoimagem , Adolescente , Emoções , Feminino , Humanos , Imaginação , Masculino , Estudos Prospectivos , Adulto Jovem
17.
Artigo em Inglês | MEDLINE | ID: mdl-32899508

RESUMO

Attachment insecurity has been associated with negative behaviors during conflict and decreased relationship satisfaction. We theorize that individuals high in attachment anxiety and/or avoidance are less mindful during conflict with their romantic partners, and thus more likely to ruminate. Decreased mindfulness and higher levels of rumination may be important mechanisms in the relationship between attachment insecurity and conflict behavior, as it may be more difficult to engage in constructive problem-solving skills when one is distracted from the present moment. We conducted an online survey assessing 360 participants' attachment orientations, levels of mindfulness and rumination, behavior during conflict, and experience with mindfulness activities. Using a serial mediation model, we found that mindfulness and rumination mediated the relationship between attachment insecurity and negative conflict behaviors. We further discovered that individuals high in attachment insecurity were more likely to report negative experiences with mindfulness activities (i.e., meditation and yoga), and that this relationship was mediated by higher levels of experiential avoidance, or a fear of engaging with one's own thoughts and feelings. We discuss the importance of increasing mindfulness and decreasing both rumination and experiential avoidance to assist individuals high in attachment insecurity in navigating relationship conflict using more constructive and relationship-promoting strategies.


Assuntos
Ansiedade , Atenção Plena , Satisfação Pessoal , Humanos , Apego ao Objeto , Parceiros Sexuais , Yoga
18.
Pers Soc Psychol Bull ; 46(5): 709-722, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31535955

RESUMO

Previous work has reliably demonstrated that when people experience more subjective ambivalence about an attitude object, their attitudes have less impact on strength-related outcomes such as attitude-related thinking, judging, or behaving. However, previous research has not considered whether the amount of perceived knowledge a person has about the topic might moderate these effects. Across eight studies on different topics using a variety of outcome measures, the current research demonstrates that perceived knowledge can moderate the relation between ambivalence and the impact of attitudes on related thinking, judging, and behaving. Although the typical Attitude × Ambivalence effect emerged when participants had relatively high perceived knowledge, this interaction did not emerge when participants were lower in perceived knowledge. This work provides a more nuanced view of the effects of subjective ambivalence on attitude impact and highlights the importance of understanding the combined impact of attitude strength antecedents.


Assuntos
Atitude , Conhecimento , Autoimagem , Adulto , Afeto , Feminino , Humanos , Masculino , Adulto Jovem
19.
Nat Metab ; 2(9): 902-917, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32694831

RESUMO

Increased aerobic exercise capacity, as a result of exercise training, has important health benefits. However, some individuals are resistant to improvements in exercise capacity, probably due to undetermined genetic and environmental factors. Here, we show that exercise-induced improvements in aerobic capacity are blunted and aerobic remodelling of skeletal muscle is impaired in several animal models associated with chronic hyperglycaemia. Our data point to chronic hyperglycaemia as a potential negative regulator of aerobic adaptation, in part, via glucose-mediated modifications of the extracellular matrix, impaired vascularization and aberrant mechanical signalling in muscle. We also observe low exercise capacity and enhanced c-Jun N-terminal kinase activation in response to exercise in humans with impaired glucose tolerance. Our work indicates that current shifts in dietary and metabolic health, associated with increasing incidence of hyperglycaemia, might impair muscular and organismal adaptations to exercise training, including aerobic capacity as one of its key health outcomes.


Assuntos
Adaptação Fisiológica/fisiologia , Aerobiose/fisiologia , Exercício Físico/fisiologia , Hiperglicemia/fisiopatologia , Músculo Esquelético/fisiopatologia , Condicionamento Físico Animal/fisiologia , Transdução de Sinais , Adulto , Limiar Anaeróbio/fisiologia , Animais , Células Endoteliais/fisiologia , Ativação Enzimática , Feminino , Intolerância à Glucose/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Masculino , Camundongos , Ratos , Adulto Jovem
20.
Biomed Pharmacother ; 117: 109197, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31387190

RESUMO

Sucrose nonfermenting AMPK-related kinase (SNARK) is a member of the AMPK family of kinases and has been implicated in the regulation of critical metabolic processes. Recent findings demonstrate that SNARK has an important role in the maintenance of muscle mass with age. Loss of skeletal muscle mass (cachexia) is a key problem for cancer patients. Thus, based on our previous findings with aging, we hypothesized that SNARK would play a role in regulating muscle mass under conditions of cancer cachexia. To test this hypothesis, Lewis Lung Carcinoma tumor cells or vehicle were injected subcutaneously in the right flank of wild type mice, muscle-specific transgenic mice expressing inactive SNARK mutant (SDN) or muscle-specific transgenic mice overexpressing wild-type SNARK (SWT). All tumor-bearing mice presented muscle wasting compared to vehicle-injected mice. However, SDN tumor-bearing mice had more pronounced atrophy compared to wild-type and SWT tumor-bearing mice. Histological analysis confirmed muscle atrophy in tumor-bearing mice, and SDN tumor-bearing mice exhibited a significantly smaller skeletal muscle cross-sectional area than wild-type and SWT tumor-bearing mice. Moreover, SDN tumor-bearing mice had increased skeletal muscle BAX protein expression, a marker of apoptosis, compared to other groups.Thus, lack of SNARK in skeletal muscle aggravates cancer-induced skeletal muscle wasting. These findings uncover a role for SNARK in the maintenance of skeletal muscle mass under cachexia conditions.


Assuntos
Carcinoma Pulmonar de Lewis/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Sacarose/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Apoptose/fisiologia , Caquexia/metabolismo , Caquexia/patologia , Carcinoma Pulmonar de Lewis/complicações , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Atrofia Muscular/etiologia
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