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1.
Infect Immun ; : e0027024, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023271

RESUMO

Bordetella pertussis, the bacterium responsible for whooping cough, remains a significant public health challenge despite the existing licensed pertussis vaccines. Current acellular pertussis vaccines, though having favorable reactogenicity and efficacy profiles, involve complex and costly production processes. In addition, acellular vaccines have functional challenges such as short-lasting duration of immunity and limited antigen coverage. Filamentous hemagglutinin (FHA) is an adhesin of B. pertussis that is included in all multivalent pertussis vaccine formulations. Antibodies to FHA have been shown to prevent bacterial attachment to respiratory epithelial cells, and T cell responses to FHA facilitate cell-mediated immunity. In this study, FHA's mature C-terminal domain (MCD) was evaluated as a novel vaccine antigen. MCD was conjugated to virus-like particles via SpyTag-SpyCatcher technology. Prime-boost vaccine studies were performed in mice to characterize immunogenicity and protection against the intranasal B. pertussis challenge. MCD-SpyVLP was more immunogenic than SpyTag-MCD antigen alone, and in Tohama I strain challenge studies, improved protection against challenge was observed in the lungs at day 3 and in the trachea and nasal wash at day 7 post-challenge. Furthermore, a B. pertussis strain encoding genetically inactivated pertussis toxin was used to evaluate MCD-SpyVLP vaccine immunity. Mice vaccinated with MCD-SpyVLP had significantly lower respiratory bacterial burden at both days 3 and 7 post-challenge compared to mock-vaccinated animals. Overall, these data support the use of SpyTag-SpyCatcher VLPs as a platform for use in vaccine development against B. pertussis and other pathogens.

2.
Infect Immun ; : e0052023, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016553

RESUMO

Bordetella pertussis is a Gram-negative bacterium that is the causative agent of the respiratory disease known as pertussis. Since the switch to the acellular vaccines of DTaP and Tap, pertussis cases in the US have risen and cyclically fallen. We have observed that mRNA pertussis vaccines are immunogenic and protective in mice. Here, we further evaluated the pertussis toxoid mRNA antigen and refined the formulation based on optimal pertussis toxin neutralization in vivo. We next evaluated the mRNA pertussis vaccine in Sprague-Dawley rats using an aerosol B. pertussis challenge model paired with whole-body plethysmography to monitor coughing and respiratory function. Female Sprague-Dawley rats were primed and boosted with either commercially available vaccines (DTaP or wP-DTP), an mRNA-DTP vaccine, or mock-vaccinated. The mRNA-DTP vaccine was immunogenic in rats and induced antigen-specific IgG antibodies comparable to DTaP. Rats were then aerosol challenged with a streptomycin-resistant emerging clinical isolate D420Sm1. Bacterial burden was assessed at days 1 and 9 post-challenge, and the mRNA vaccine reduced burden equal to both DTaP and wP-DTP. Whole-body plethysmography revealed that mRNA-DTP vaccinated rats were well protected against coughing which was comparable to the non-challenged group. These data suggest that an mRNA-DTP vaccine is immunogenic in rats and provides protection against aerosolized B. pertussis challenge in Sprague-Dawley rats.

3.
Expert Opin Drug Metab Toxicol ; : 1-6, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38957078

RESUMO

INTRODUCTION: Ibrexafungerp is a new triterpenoid antifungal agent with activity against a variety of fungal species, including Aspergillus spp. and echinocandin-resistant Candida spp. AREAS COVERED: This evaluation will summarize currently available clinical evidence on the use of ibrexafungerp in the treatment/prevention of vulvovaginal candidiasis (VVC) and detail the mechanism of action, pharmacokinetic/pharmacodynamic parameters, and ongoing/latest research involving ibrexafungerp. EXPERT OPINION: The evidence involving the utilization of ibrexafungerp for the treatment of VVC shows that it is superior when compared to placebo and has comparable clinical cure rates when compared with fluconazole. Ibrexafungerp demonstrates reliable coverage against several Candida spp. including echinocandin-resistant strains, Candida auris, and Aspergillus spp. For VVC, a dose of 300 mg (two 150 mg tablets) twice daily is recommended and does not require dose adjustments based on renal or hepatic function. The use of ibrexafungerp outside of VVC is currently under study with several ongoing trials showing promising interim data.

4.
Psychosom Med ; 86(6): 541-546, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38666648

RESUMO

OBJECTIVE: Major depressive disorder (MDD) and chronic pain are highly comorbid and bidirectionally related. Repetitive transcranial magnetic stimulation (rTMS) over the dorsolateral prefrontal cortex is effective in treating MDD, but additional research is needed to determine if chronic pain interferes with rTMS for MDD. METHODS: Participants were 124 veterans ( Mage = 49.14, SD = 13.83) scheduled for 30 sessions of rTMS across 6 weeks. Depression severity was monitored weekly using the Patient Health Questionnaire-9 (PHQ-9). Having any pain diagnosis, low back pain, or headache/migraine were assessed by chart review. We fit latent basis models to estimate total change by pain diagnosis in depression scores and quadratic latent growth models to examine differences in growth rates. Then, we computed χ2 tests of group differences in response (PHQ-9 reduction ≥50%) and remission rates (final PHQ-9 < 5). RESULTS: A total of 92 participants (74%) had a documented pain diagnosis, 58 (47%) had low back pain, and 32 (26%) had headache/migraine. In growth models, depression scores initially decreased (linear slope estimate = -2.04, SE = 0.26, p < .0001), but the rate of decrease slowed over time (quadratic slope estimate = 0.18, SE = 0.04, p < .001). Overall change was not different as a function of any pain diagnosis ( p = .42), low back pain (p = .11 ), or headache/migraine ( p = .28). However, we found that low back pain was a negative predictor of response ( p = .032). CONCLUSIONS: These data support rTMS as a viable treatment option for comorbid populations. Although patients with comorbid chronic pain conditions are likely to receive benefit from rTMS for depression, adjunctive pain treatment may be indicated.


Assuntos
Dor Crônica , Transtorno Depressivo Maior , Dor Lombar , Transtornos de Enxaqueca , Estimulação Magnética Transcraniana , Humanos , Dor Crônica/terapia , Estimulação Magnética Transcraniana/métodos , Masculino , Pessoa de Meia-Idade , Feminino , Transtorno Depressivo Maior/terapia , Adulto , Transtornos de Enxaqueca/terapia , Dor Lombar/terapia , Veteranos , Comorbidade , Córtex Pré-Frontal Dorsolateral , Idoso , Resultado do Tratamento
5.
Infect Immun ; 92(3): e0022323, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38323817

RESUMO

The protection afforded by acellular pertussis vaccines wanes over time, and there is a need to develop improved vaccine formulations. Options to improve the vaccines involve the utilization of different adjuvants and administration via different routes. While intramuscular (IM) vaccination provides a robust systemic immune response, intranasal (IN) vaccination theoretically induces a localized immune response within the nasal cavity. In the case of a Bordetella pertussis infection, IN vaccination results in an immune response that is similar to natural infection, which provides the longest duration of protection. Current acellular formulations utilize an alum adjuvant, and antibody levels wane over time. To overcome the current limitations with the acellular vaccine, we incorporated a novel TLR4 agonist, BECC438b, into both IM and IN acellular formulations to determine its ability to protect against infection in a murine airway challenge model. Following immunization and challenge, we observed that DTaP + BECC438b reduced bacterial burden within the lung and trachea for both administration routes when compared with mock-vaccinated and challenged (MVC) mice. Interestingly, IN administration of DTaP + BECC438b induced a Th1-polarized immune response, while IM vaccination polarized toward a Th2 immune response. RNA sequencing analysis of the lung demonstrated that DTaP + BECC438b activates biological pathways similar to natural infection. Additionally, IN administration of DTaP + BECC438b activated the expression of genes involved in a multitude of pathways associated with the immune system. Overall, these data suggest that BECC438b adjuvant and the IN vaccination route can impact efficacy and responses of pertussis vaccines in pre-clinical mouse models.


Assuntos
Vacinas contra Difteria, Tétano e Coqueluche Acelular , Coqueluche , Animais , Camundongos , Coqueluche/prevenção & controle , Receptor 4 Toll-Like , Vacina contra Coqueluche , Vacina contra Difteria, Tétano e Coqueluche , Bordetella pertussis , Adjuvantes Imunológicos , Imunidade , Anticorpos Antibacterianos
6.
PLoS One ; 18(11): e0286925, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37917623

RESUMO

The murine Bordetella pertussis challenge model has been utilized in preclinical research for decades. Currently, inconsistent methodologies are employed by researchers across the globe, making it difficult to compare findings. The objective of this work was to utilize the CD-1 mouse model with two routes of challenge, intranasal and aerosol administration of B. pertussis, to understand the differences in disease manifestation elicited via each route. We observed that both routes of B. pertussis challenge result in dose-dependent colonization of the respiratory tract, but overall, intranasal challenge led to higher bacterial burden in the nasal lavage, trachea, and lung. Furthermore, high dose intranasal challenge results in induction of leukocytosis and pro-inflammatory cytokine responses compared to aerosol challenge. These data highlight crucial differences in B. pertussis challenge routes that should be considered during experimental design.


Assuntos
Bordetella pertussis , Coqueluche , Animais , Camundongos , Camundongos Endogâmicos BALB C , Aerossóis e Gotículas Respiratórios , Administração Intranasal , Vacina contra Coqueluche
7.
Psychol Serv ; 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37824243

RESUMO

Racial, ethnic, and gender health care disparities in the United States are well-documented and stretch across the lifespan. Even in large integrated health care systems such as Veteran Health Administration, which are designed to provide equality in care, social and economic disparities persist, and limit patients' achievement of health goals across multiple domains. We explore Veterans' Whole Health priorities among Veteran demographic groups. Participants who were enrolling in Veteran Health Administration provided demographics and Whole Health priorities using eScreening, a web-based self-assessment tool. Veterans had similar health care goals regardless of demographic characteristics but differences were noted in current health appraisals. Non-White and women Veterans reported worse health-relevant functioning. Black Veterans were more likely to endorse a low rating for their personal development/relationships. Multiracial Veterans were more likely to endorse a low rating of their surroundings. Asian Veterans were less likely to provide a high rating of their surroundings. Women Veterans reported lower appraisals for body and personal development but higher appraisals of professional care. Results indicated that demographic factors such as race and gender, and to a lesser extent ethnicity, were associated with health disparities. The Whole Health model provides a holistic framework for addressing these disparities. These findings may inform more culturally sensitive care and enhance Veteran Health Administration equal access initiatives. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

8.
Front Cell Infect Microbiol ; 13: 1191806, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37424774

RESUMO

Pseudomonas aeruginosa is a common cause of hospital-acquired infections, including central line-associated bloodstream infections and ventilator-associated pneumonia. Unfortunately, effective control of these infections can be difficult, in part due to the prevalence of multi-drug resistant strains of P. aeruginosa. There remains a need for novel therapeutic interventions against P. aeruginosa, and the use of monoclonal antibodies (mAb) is a promising alternative strategy to current standard of care treatments such as antibiotics. To develop mAbs against P. aeruginosa, we utilized ammonium metavanadate, which induces cell envelope stress responses and upregulates polysaccharide expression. Mice were immunized with P. aeruginosa grown with ammonium metavanadate and we developed two IgG2b mAbs, WVDC-0357 and WVDC-0496, directed against the O-antigen lipopolysaccharide of P. aeruginosa. Functional assays revealed that WVDC-0357 and WVDC-0496 directly reduced the viability of P. aeruginosa and mediated bacterial agglutination. In a lethal sepsis model of infection, prophylactic treatment of mice with WVDC-0357 and WVDC-0496 at doses as low as 15 mg/kg conferred 100% survival against challenge. In both sepsis and acute pneumonia models of infection, treatment with WVDC-0357 and WVDC-0496 significantly reduced bacterial burden and inflammatory cytokine production post-challenge. Furthermore, histopathological examination of the lungs revealed that WVDC-0357 and WVDC-0496 reduced inflammatory cell infiltration. Overall, our results indicate that mAbs directed against lipopolysaccharide are a promising therapy for the treatment and prevention of P. aeruginosa infections.


Assuntos
Anticorpos Antibacterianos , Anticorpos Monoclonais , Lipopolissacarídeos , Infecções por Pseudomonas , Pseudomonas aeruginosa , Animais , Feminino , Camundongos , Anticorpos Antibacterianos/imunologia , Anticorpos Monoclonais/imunologia , Aderência Bacteriana , Carga Bacteriana/imunologia , Convalescença , Mediadores da Inflamação/imunologia , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/imunologia , Pneumonia Bacteriana/imunologia , Pneumonia Bacteriana/microbiologia , Pneumonia Bacteriana/prevenção & controle , Pseudomonas aeruginosa/imunologia , Infecções por Pseudomonas/imunologia , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/prevenção & controle , Sepse/imunologia , Sepse/microbiologia , Sepse/prevenção & controle
9.
Front Cell Infect Microbiol ; 13: 1117844, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37124031

RESUMO

The rise of antimicrobial-resistant bacterial infections is a crucial health concern in the 21st century. In particular, antibiotic-resistant Pseudomonas aeruginosa causes difficult-to-treat infections associated with high morbidity and mortality. Unfortunately, the number of effective therapeutic interventions against antimicrobial-resistant P. aeruginosa infections continues to decline. Therefore, discovery and development of alternative treatments are necessary. Here, we present pre-clinical efficacy studies on an anti-P. aeruginosa therapeutic monoclonal antibody. Using hybridoma technology, we generated a monoclonal antibody and characterized its binding to P. aeruginosa in vitro using ELISA and fluorescence correlation spectroscopy. We also characterized its function in vitro and in vivo against P. aeruginosa. The anti-P. aeruginosa antibody (WVDC-5244) bound P. aeruginosa clinical strains of various serotypes in vitro, even in the presence of alginate exopolysaccharide. In addition, WVDC-5244 induced opsonophagocytic killing of P. aeruginosa in vitro in J774.1 murine macrophage, and complement-mediated killing. In a mouse model of acute pneumonia, prophylactic administration of WVDC-5244 resulted in an improvement of clinical disease manifestations and reduction of P. aeruginosa burden in the respiratory tract compared to the control groups. This study provides promising pre-clinical efficacy data on a new monoclonal antibody with therapeutic potential for P. aeruginosa infections.


Assuntos
Pneumonia , Infecções por Pseudomonas , Camundongos , Animais , Pseudomonas aeruginosa , Pneumonia/microbiologia , Anticorpos Monoclonais/uso terapêutico , Hibridomas/metabolismo , Proteínas do Sistema Complemento , Infecções por Pseudomonas/microbiologia
10.
Contemp Clin Trials ; 127: 107118, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36796623

RESUMO

BACKGROUND: Disparities in physical and mental health among Black, Indigenous, and People of Color (BIPOC) are well-documented and mirrored in the Veteran population. Chronic stress due to racism and discrimination is one possible mechanism driving these negative health outcomes. The Race-Based Stress and Trauma Empowerment (RBSTE) group is a novel, manualized, health promotion intervention designed to address the direct and indirect impacts of racism among Veterans of Color. This paper describes the protocol of the first pilot randomized controlled trial (RCT) of RBSTE. This study will examine the feasibility, acceptability, and appropriateness of RBSTE compared to an active control (an adaptation of Present-Centered Therapy; PCT) in a Veterans Affairs (VA) healthcare setting. A secondary aim is to identify and optimize strategies for holistic evaluation. METHODS: Veterans of Color (N = 48) endorsing perceived discrimination and stress will be randomized to RBSTE or PCT; both groups will be delivered in 8 weekly, 90-min virtual group sessions. Outcomes will include measures of psychological distress, discrimination and ethnoracial identity, holistic wellness, and allostatic load. Measures will be administered at baseline and post-intervention. CONCLUSION: This study will inform future interventions targeting identity-based stressors and represents an important step in advancing equity for BIPOC in medicine and research. CLINICAL TRIAL REGISTRATION NUMBER: NCT05422638.


Assuntos
Racismo , Racismo Sistêmico , Humanos , Racismo/psicologia , Atenção à Saúde , Saúde Mental
12.
NPJ Vaccines ; 7(1): 143, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36357402

RESUMO

Whole cell vaccines are complex mixtures of antigens, immunogens, and sometimes adjuvants that can trigger potent and protective immune responses. In some instances, such as whole cell Bordetella pertussis vaccination, the immune response to vaccination extends beyond the pathogen the vaccine was intended for and contributes to protection against other clinically significant pathogens. In this study, we describe how B. pertussis whole cell vaccination protects mice against acute pneumonia caused by Pseudomonas aeruginosa. Using ELISA and western blot, we identified that B. pertussis whole cell vaccination induces production of antibodies that bind to lab-adapted and clinical strains of P. aeruginosa, regardless of immunization route or adjuvant used. The cross-reactive antigens were identified using immunoprecipitation, mass spectrometry, and subsequent immunoblotting. We determined that B. pertussis GroEL and OmpA present in the B. pertussis whole cell vaccine led to production of antibodies against P. aeruginosa GroEL and OprF, respectively. Finally, we showed that recombinant B. pertussis OmpA was sufficient to induce protection against P. aeruginosa acute murine pneumonia. This study highlights the potential for use of B. pertussis OmpA as a vaccine antigen for prevention of P. aeruginosa infection, and the potential of broadly protective antigens for vaccine development.

13.
J Affect Disord ; 308: 106-110, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35429530

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic led to the onset and exacerbation of mental health problems, such as stress, anxiety, and depression; yet stay-at-home-orders affected individuals' ability to make use of social support as a coping skill in managing distress. We aimed to evaluate how social support (emotional and instrumental) and biological sex were associated with stress, anxiety, and depression early in the COVID-19 pandemic. METHODS: Participants (n = 7256) had an average age of 50.13 years (SD = 16.75) and 51.6% were male. Using a cross-sequential design, seven cohorts of individuals completed baseline (T1) and one-month follow-up (T2) questionnaires online from March to July of 2020. We used a series of hierarchical regressions to identify types of social support (Brief-COPE, T1) associated with stress (Perceived Stress Scale-10, T1 and T2), anxiety and depression (Patient Health Questionnaire-4, T2). RESULTS: Greater emotional support was associated with less perceived stress, anxiety and depression (all ps < 0.001), whereas greater instrumental support predicted increased distress (all ps < 0.036) on all four outcomes. Moderation analyses revealed that greater emotional social support was associated with lower perceived stress at T1 for both women and men, with a stronger association for women relative to men. For women, greater emotional social support predicted lower anxiety. LIMITATIONS: Self-selection may have introduced bias and participant self-report on brief measures may not have fully captured coping and distress. CONCLUSIONS: Interventions enhancing emotional social support strategies, which appear especially important for women, might help manage enduring stressors such as the COVID-19 pandemic.


Assuntos
COVID-19 , Angústia Psicológica , Adaptação Psicológica , Ansiedade/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Apoio Social , Estresse Psicológico/epidemiologia
14.
Front Immunol ; 13: 838504, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35211125

RESUMO

Over two decades ago acellular pertussis vaccines (aP) replaced whole cell pertussis vaccines (wP) in several countries. Since then, a resurgence in pertussis has been observed, which is hypothesized to be linked, in part, to waning immunity. To better understand why waning immunity occurs, we developed a long-term outbred CD1 mouse model to conduct the longest murine pertussis vaccine studies to date, spanning out to 532 days post primary immunization. Vaccine-induced memory results from follicular responses and germinal center formation; therefore, cell populations and cytokines involved with memory were measured alongside protection from challenge. Both aP and wP immunization elicit protection from intranasal challenge by decreasing bacterial burden in both the upper and lower airways, and by generation of pertussis specific antibody responses in mice. Responses to wP vaccination were characterized by a significant increase in T follicular helper cells in the draining lymph nodes and CXCL13 levels in sera compared to aP mice. In addition, a population of B. pertussis+ memory B cells was found to be unique to wP vaccinated mice. This population peaked post-boost, and was measurable out to day 365 post-vaccination. Anti-B. pertussis and anti-pertussis toxoid antibody secreting cells increased one day after boost and remained high at day 532. The data suggest that follicular responses, and in particular CXCL13 levels in sera, could be monitored in pre-clinical and clinical studies for the development of the next-generation pertussis vaccines.


Assuntos
Bordetella pertussis/imunologia , Vacina contra Coqueluche/imunologia , Células T Auxiliares Foliculares/imunologia , Coqueluche/imunologia , Animais , Anticorpos Antibacterianos/sangue , Quimiocina CXCL13/sangue , Imunização Secundária , Memória Imunológica , Camundongos , Fatores de Tempo , Vacinação , Coqueluche/prevenção & controle
15.
J Affect Disord Rep ; 8: 100325, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35169766

RESUMO

BACKGROUND: The COVID-19 pandemic has led to psychological distress among community samples and university students. Some coping behaviors and cognitive appraisals allow individuals to experience positive psychological growth amid such a crisis (Folkman et al. 1986). In the event of continuing waves of COVID-19 infection and future viral outbreaks, understanding the relationships between coping behaviors, stress appraisals, and COVID-related distress and growth can empower public health officials and university leadership to mitigate negative consequences and encourage growth. METHODS: 774 undergraduate students completed online self-report measures of coping (Brief COPE; emotion, problem, avoidant), stress appraisal (SAM; threat/centrality, challenge/self-efficacy, uncontrol, other-control), neuroticism (NEO-N), health anxiety (SHAI), and COVID-19 exposure/impact (C-PIQ; distress and growth). Hypotheses were examined via simple regressions and interactions. RESULTS: Increased utilization of avoidant coping was associated with high levels of distress regardless of whether it was perceived as threatening or not. Emotion-focused and problem-focused coping strategies were associated with more growth, whereas avoidant coping was associated with less growth. Higher emotion-focused coping and challenge appraisal together predicted the most growth. LIMITATIONS: Cross-sectional design precludes the tracking of distress and growth over time; this study relied on self-report data. CONCLUSIONS: These results underscore the impact of stress appraisals on the mental health of students navigating the COVID-19 pandemic. Findings may inform public health messaging-or have clinical implications, as successful interventions exist for improving coping strategies and stress appraisals.

16.
Endocrinology ; 162(8)2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34043793

RESUMO

Free fatty acids (FFAs) are implicated in the pathogenesis of metabolic diseases that includes obesity, type 2 diabetes mellitus, and cardiovascular disease (CVD). FFAs serve as ligands for free fatty acid receptors (FFARs) that belong to the family of rhodopsin-like G protein-coupled receptors (GPCRs) and are expressed throughout the body to maintain energy homeostasis under changing nutritional conditions. Free fatty acid receptor 4 (FFAR4), also known as G protein-coupled receptor 120, is a long-chain fatty acid receptor highly expressed in adipocytes, endothelial cells, and macrophages. Activation of FFAR4 helps maintain metabolic homeostasis by regulating adipogenesis, insulin sensitivity, and inflammation. Furthermore, dysfunction of FFAR4 is associated with insulin resistance, obesity, and eccentric remodeling in both humans and mice, making FFAR4 an attractive therapeutic target for treating or preventing metabolic diseases. While much of the previous literature on FFAR4 has focused on its role in obesity and diabetes, recent studies have demonstrated that FFAR4 may also play an important role in the development of atherosclerosis and CVD. Most notably, FFAR4 activation reduces monocyte-endothelial cell interaction, enhances cholesterol efflux from macrophages, reduces lesion size in atherogenic mouse models, and stimulates oxylipin production in myocytes that functions in a feed-forward cardioprotective mechanism. This review will focus on the role of FFAR4 in metabolic diseases and highlights an underappreciated role of FFAR4 in the development of atherosclerosis and CVD.


Assuntos
Aterosclerose/etiologia , Síndrome Metabólica/etiologia , Receptores Acoplados a Proteínas G/metabolismo , Animais , Aterosclerose/metabolismo , Humanos , Síndrome Metabólica/metabolismo , Receptores Acoplados a Proteínas G/genética
17.
FEBS Lett ; 594(2): 337-357, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514245

RESUMO

Fumarase C (FumC) catalyzes the reversible conversion of fumarate to S-malate. Previous structural investigations within the superfamily have reported a dynamic structural segment, termed the SS Loop. To date, active-site asymmetry has raised the question of how SS Loop placement affects participation of key residues during the reaction. Herein, we report structural and kinetic analyses from Escherichia coli FumC variants to understand the contribution of SS Loop residues S318, K324, and N326. High-resolution X-ray crystallographic results reveal three distinct FumC active-site conformations; disordered-open, ordered-open, and the newly discovered ordered-closed. Surprisingly, each SS Loop variant has unaffected Michaelis constants coupled to reductions in turnover number. Based upon our structural and functional analyses, we propose structural and catalytic roles for each of the aforementioned residues.


Assuntos
Catálise , Fumarato Hidratase/ultraestrutura , Conformação Proteica , Sequência de Aminoácidos/genética , Domínio Catalítico/genética , Cristalografia por Raios X , Escherichia coli/enzimologia , Fumarato Hidratase/química , Fumarato Hidratase/genética , Cinética , Modelos Moleculares
18.
R Soc Open Sci ; 5(8): 180493, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30225039

RESUMO

Triploidy could prevent escaped farm salmon breeding in the wild, while also improving nutrient quality within farmed fillets. Despite these potential advantages, triploid Atlantic salmon have not been widely used in aquaculture, and their reproductive function has yet to be fully evaluated. Here, we compare reproductive function and fillet composition between triploid and diploid farm salmon under standard aquaculture rearing conditions. We show that female triploids are sterile and do not develop gonads. By contrast, males produce large numbers of motile spermatozoa capable of fertilizing wild salmon eggs. However, compared with diploids, reproductive development and survival rates of eggs fertilized by triploid males were significantly reduced, with less than 1% of eggs sired by triploid males reaching late-eyed stages of development. Analyses of fillets showed that total lipid and fatty acid quantities were significantly lower in triploid than in diploid Atlantic salmon fillets. However, when fatty acids were normalized to total lipid content, triploid fillets had significantly higher relative levels of important omega-3 long-chain polyunsaturated fatty acids. Our results show that: (i) escaped triploid farm salmon are very unlikely to reproduce in the wild and (ii) if able to match diploid fillet lipid content, triploid farm salmon could achieve better fillet quality in terms of essential fatty acids.

19.
Proc Natl Acad Sci U S A ; 115(28): E6556-E6565, 2018 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-29950315

RESUMO

Macrophages are key immune cells for the initiation and development of atherosclerotic lesions. However, the macrophage regulatory nodes that determine how lesions progress in response to dietary challenges are not fully understood. Liver X receptors (LXRs) are sterol-regulated transcription factors that play a central role in atherosclerosis by integrating cholesterol homeostasis and immunity. LXR pharmacological activation elicits a robust antiatherosclerotic transcriptional program in macrophages that can be affected by LXRα S196 phosphorylation in vitro. To investigate the impact of these transcriptional changes in atherosclerosis development, we have generated mice carrying a Ser-to-Ala mutation in myeloid cells in the LDL receptor (LDLR)-deficient atherosclerotic background (M-S196ALdlr-KO). M-S196ALdlr-KO mice fed a high-fat diet exhibit increased atherosclerotic plaque burden and lesions with smaller necrotic cores and thinner fibrous caps. These diet-induced phenotypic changes are consistent with a reprogramed macrophage transcriptome promoted by LXRα-S196A during atherosclerosis development. Remarkably, expression of several proliferation-promoting factors, including the protooncogene FoxM1 and its targets, is induced by LXRα-S196A. This is consistent with increased proliferation of plaque-resident cells in M-S196ALdlr-KO mice. Moreover, disrupted LXRα phosphorylation increases expression of phagocytic molecules, resulting in increased apoptotic cell removal by macrophages, explaining the reduced necrotic cores. Finally, the macrophage transcriptome promoted by LXRα-S196A under dietary perturbation is markedly distinct from that revealed by LXR ligand activation, highlighting the singularity of this posttranslational modification. Overall, our findings demonstrate that LXRα phosphorylation at S196 is an important determinant of atherosclerotic plaque development through selective changes in gene transcription that affect multiple pathways.


Assuntos
Aterosclerose/metabolismo , Proteína Forkhead Box M1/biossíntese , Regulação da Expressão Gênica , Receptores X do Fígado/metabolismo , Macrófagos/metabolismo , Mutação de Sentido Incorreto , Substituição de Aminoácidos , Animais , Aterosclerose/genética , Aterosclerose/patologia , Proliferação de Células , Proteína Forkhead Box M1/genética , Receptores X do Fígado/genética , Macrófagos/patologia , Camundongos , Camundongos Knockout , Fosforilação
20.
Ann Oncol ; 29(5): 1280-1285, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29788166

RESUMO

Background: The 21-gene recurrence score (RS) (Oncotype DX®; Genomic Health, Redwood City, CA) partitions hormone receptor positive, node negative breast cancers into three risk groups for recurrence. The Anne Arundel Medical Center (AAMC) model has previously been shown to accurately predict RS risk categories using standard pathology data. A pathologic-genomic (P-G) algorithm then is presented using the AAMC model and reserving the RS assay only for AAMC intermediate-risk patients. Patients and methods: A survival analysis was done using a prospectively collected institutional database of newly diagnosed invasive breast cancers that underwent RS assay testing from February 2005 to May 2015. Patients were assigned to risk categories based on the AAMC model. Using Kaplan-Meier methods, 5-year distant recurrence rates (DRR) were evaluated within each risk group and compared between AAMC and RS-defined risk groups. Five-year DRR were calculated for the P-G algorithm and compared with DRR for RS risk groups and the AAMC model's risk groups. Results: A total of 1268 cases were included. Five-year DRR were similar between the AAMC low-risk group (2.7%, n = 322) and the RS < 18 low-risk group (3.4%, n = 703), as well as between the AAMC high-risk group (22.8%, n = 230) and the RS > 30 high-risk group (23.0%, n = 141). Using the P-G algorithm, more patients were categorized as either low or high risk and the distant metastasis rate was 3.3% for the low-risk group (n = 739) and 24.2% for the high-risk group (n = 272). Using the P-G algorithm, 44% (552/1268) of patients would have avoided RS testing. Conclusions: AAMC model is capable of predicting 5-year recurrences in high- and low-risk groups similar to RS. Further, using the P-G algorithm, reserving RS for AAMC intermediate cases, results in larger low- and high-risk groups with similar prognostic accuracy. Thus, the P-G algorithm reliably identifies a significant portion of patients unlikely to benefit from RS assay and with improved ability to categorize risk.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/patologia , Testes Genéticos/métodos , Modelos Genéticos , Recidiva Local de Neoplasia/diagnóstico , Algoritmos , Mama/patologia , Mama/cirurgia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Quimioterapia Adjuvante/métodos , Análise Custo-Benefício , Feminino , Seguimentos , Testes Genéticos/economia , Humanos , Incidência , Mastectomia , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/prevenção & controle , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Medição de Risco/economia , Medição de Risco/métodos , Fatores de Tempo , Resultado do Tratamento , Carga Tumoral/genética
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