Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
1.
J Clin Periodontol ; 50(12): 1670-1684, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37667415

RESUMO

AIM: Antimicrobial-induced shifts in commensal oral microbiota can dysregulate helper T-cell oral immunity to affect osteoclast-osteoblast actions in alveolar bone. Antibiotic prophylaxis is commonly performed with dental implant placement surgery to prevent post-surgical complications. However, antibiotic prophylaxis effects on osteoimmune processes supporting dental implant osseointegration are unknown. The aim of the study was to discern the impact of antibiotic prophylaxis on dental implant placement surgery-induced osteoimmune wound healing and osseointegration. MATERIALS AND METHODS: We performed SHAM or dental implant placement surgery in mice. Groups were administered prophylactic antibiotics (amoxicillin or clindamycin) or vehicle. Gingival bacteriome was assessed via 16S sequencing. Helper T-cell oral immunity was evaluated by flow cytometry. Osteoclasts and osteoblasts were assessed via histomorphometry. Implant osseointegration was evaluated by micro-computed tomography. RESULTS: Dental implant placement surgery up-regulated TH 1, TH 2 and TREG cells in cervical lymph nodes (CLNs), which infers helper T-cell oral immunity contributes to dental implant placement osseous wound healing. Prophylactic antibiotics with dental implant placement surgery caused a bacterial dysbiosis, suppressed TH 1, TH 2 and TREG cells in CLNs, reduced osteoclasts and osteoblasts lining peri-implant alveolar bone, and attenuated the alveolar bone-implant interface. CONCLUSIONS: Antibiotic prophylaxis dysregulates dental implant placement surgery-induced osteoimmune wound healing and attenuates the alveolar bone-implant interface in mice.


Assuntos
Implantes Dentários , Animais , Camundongos , Antibioticoprofilaxia , Interface Osso-Implante , Microtomografia por Raio-X , Implantação Dentária Endóssea/métodos , Osseointegração/fisiologia , Cicatrização/fisiologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
2.
Am J Pathol ; 193(6): 796-812, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36906264

RESUMO

Antibiotic administration during early life has been shown to have lasting effects on the gut microbiota, which have been linked to sustained alterations in liver metabolism and adiposity. Recent investigations have discerned that the gut microbiota continues to develop toward an adult-like profile during adolescence. However, the impact of antibiotic exposure during adolescence on metabolism and adiposity is unclear. Herein, a retrospective analysis of Medicaid claims data was performed, which indicated that tetracycline class antibiotics are commonly prescribed for the systemic treatment of adolescent acne. The purpose of this was to discern the impact of a prolonged tetracycline antibiotic exposure during adolescence on the gut microbiota, liver metabolism, and adiposity. Male C57BL/6T specific pathogen-free mice were administered a tetracycline antibiotic during the pubertal/postpubertal adolescent growth phase. Groups were euthanized at different time points to assess immediate and sustained antibiotic treatment effects. Antibiotic exposure during adolescence caused lasting genera-level shifts in the intestinal bacteriome and persistent dysregulation of metabolic pathways in the liver. Dysregulated hepatic metabolism was linked to sustained disruption of the intestinal farnesoid X receptor-fibroblast growth factor 15 axis, a gut-liver endocrine axis that supports metabolic homeostasis. Antibiotic exposure during adolescence increased subcutaneous, visceral, and marrow adiposity, which intriguingly manifested following antibiotic therapy. This preclinical work highlights that prolonged antibiotic courses for the clinical treatment of adolescent acne may have unintended deleterious effects on liver metabolism and adiposity.


Assuntos
Adiposidade , Antibacterianos , Masculino , Camundongos , Animais , Antibacterianos/efeitos adversos , Estudos Retrospectivos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Fígado/metabolismo , Tetraciclinas/metabolismo
3.
Bone Rep ; 18: 101662, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36860797

RESUMO

Osteoimmune studies have identified complement signaling as an important regulator of the skeleton. Specifically, complement anaphylatoxin receptors (i.e., C3aR, C5aR) are expressed on osteoblasts and osteoclasts, implying that C3a and/or C5a may be candidate mediators of skeletal homeostasis. The study aimed to determine how complement signaling influences bone modeling/remodeling in the young skeleton. Female C57BL/6J C3aR-/-C5aR-/- vs. wildtype and C3aR-/- vs. wildtype mice were examined at age 10 weeks. Trabecular and cortical bone parameters were analyzed by micro-CT. In situ osteoblast and osteoclast outcomes were determined by histomorphometry. Osteoblast and osteoclast precursors were assessed in vitro. C3aR-/-C5aR-/- mice displayed an increased trabecular bone phenotype at age 10 weeks. In vitro studies revealed C3aR-/-C5aR-/- vs. wildtype cultures had less bone-resorbing osteoclasts and increased bone-forming osteoblasts, which were validated in vivo. To determine whether C3aR alone was critical for the enhanced skeletal outcomes, wildtype vs. C3aR-/- mice were evaluated for osseous tissue outcomes. Paralleling skeletal findings in C3aR-/-C5aR-/- mice, C3aR-/- vs. wildtype mice had an enhanced trabecular bone volume fraction, which was attributed to increased trabecular number. There was elevated osteoblast activity and suppressed osteoclastic cells in C3aR-/- vs. wildtype mice. Furthermore, primary osteoblasts derived from wildtype mice were stimulated with exogenous C3a, which more profoundly upregulated C3ar1 and the pro-osteoclastic chemokine Cxcl1. This study introduces the C3a/C3aR signaling axis as a novel regulator of the young skeleton.

4.
Lab Anim ; 57(1): 87-88, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36825390
5.
JCI Insight ; 8(1)2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36413391

RESUMO

Antibiotic-induced shifts in the indigenous gut microbiota influence normal skeletal maturation. Current theory implies that gut microbiota actions on bone occur through a direct gut/bone signaling axis. However, our prior work supports that a gut/liver signaling axis contributes to gut microbiota effects on bone. Our purpose was to investigate the effects of minocycline, a systemic antibiotic treatment for adolescent acne, on pubertal/postpubertal skeletal maturation. Sex-matched specific pathogen-free (SPF) and germ-free (GF) C57BL/6T mice were administered a clinically relevant minocycline dose from age 6-12 weeks. Minocycline caused dysbiotic shifts in the gut bacteriome and impaired skeletal maturation in SPF mice but did not alter the skeletal phenotype in GF mice. Minocycline administration in SPF mice disrupted the intestinal farnesoid X receptor/fibroblast growth factor 15 axis, a gut/liver endocrine axis supporting systemic bile acid homeostasis. Minocycline-treated SPF mice had increased serum conjugated bile acids that were farnesoid X receptor (FXR) antagonists, suppressed osteoblast function, decreased bone mass, and impaired bone microarchitecture and fracture resistance. Stimulating osteoblasts with the serum bile acid profile from minocycline-treated SPF mice recapitulated the suppressed osteogenic phenotype found in vivo, which was mediated through attenuated FXR signaling. This work introduces bile acids as a potentially novel mediator of gut/liver signaling actions contributing to gut microbiota effects on bone.


Assuntos
Minociclina , Osteogênese , Animais , Camundongos , Antibacterianos/efeitos adversos , Ácidos e Sais Biliares/metabolismo , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Minociclina/farmacologia
6.
Bone ; 159: 116377, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35248788

RESUMO

Tetracyclines are a broad-spectrum class of antibiotics that have unclear actions with potentially lasting effects on bone metabolism. Initially isolated from Streptomyces, tetracycline proved to be an effective treatment for Gram +/- infections. The emergence of resistant bacterial strains commanded the development of later generation agents, including minocycline, doxycycline, tigecycline, sarecycline, omadacycline, and eravacycline. In 1957, it was realized that tetracyclines act as bone fluorochrome labels due to their high affinity for the bone mineral matrix. Over the course of the next decade, researchers discerned that these compounds are retained in the bone matrix at high levels after the termination of antibiotic therapy. Studies during this period provided evidence that tetracyclines could disrupt prenatal and early postnatal skeletal development. Currently, tetracyclines are most commonly prescribed as a long-term systemic therapy for the treatment of acne in healthy adolescents and young adults. Surprisingly, the impact of tetracyclines on physiologic bone modeling/remodeling is largely unknown. This article provides an overview of the pharmacology of tetracycline drugs, summarizes current knowledge about the impact of these agents on skeletal development and homeostasis, and reviews prior work targeting tetracyclines' effects on bone cell physiology. The need for future research to elucidate unclear effects of tetracyclines on the skeleton is addressed, including drug retention/release mechanisms from the bone matrix, signaling mechanisms at bone cells, the impact of newer third generation tetracycline antibiotics, and the role of the gut-bone axis.


Assuntos
Acne Vulgar , Tetraciclina , Acne Vulgar/tratamento farmacológico , Adolescente , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Humanos , Minociclina/farmacologia , Minociclina/uso terapêutico , Tetraciclina/uso terapêutico
7.
Nurs Forum ; 57(1): 34-41, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34535901

RESUMO

PURPOSE: Gender affirmation lessens mental health disparities among transgender and gender nonbinary (TGNB) persons. However, the concept of what it means to be affirmed in one's gender has not been fully explored, nor has the impact of gender affirmation on other health indicators been determined. The purpose of this study was to explore the meaning of gender affirmation among a sample of TGNB persons. METHODS: This qualitative, narrative inquiry study consisted of individual, in-depth, semi-structured interviews with a convenience sample of 20 TGNB persons. Descriptive content analysis was conducted to discover themes. RESULTS: This study identified salient themes regarding the multiple levels of affirmation (including internal, external and societal) needed to achieve the overall goal of living an optimal life described as "being seen, heard and even celebrated" as TGNB. CONCLUSION: Results of this study have clinical, educational, research, and policy implications. Future research should explore the impact of gender affirmation on important health indicators in the TGNB community, differences in the experiences and needs among subgroups of TGNB persons, and the potential impact of nurses on the health experience of TGNB persons across the spectrum of transition.


Assuntos
Pessoas Transgênero , Transexualidade , Identidade de Gênero , Humanos
8.
Lab Invest ; 102(4): 363-375, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34934182

RESUMO

The alveolar bone is a unique osseous tissue due to the presence of the teeth and the proximity of commensal oral microbes. Commensal microbe effects on alveolar bone homeostasis have been attributed to the oral microbiota, yet the impact of commensal gut microbes is unknown. Study purpose was to elucidate whether commensal gut microbes regulate osteoimmune mechanisms and skeletal homeostasis in alveolar bone. Male C57BL/6T germfree (GF) littermate mice were maintained as GF or monoassociated with segmented filamentous bacteria (SFB), a commensal gut bacterium. SFB has been shown to elicit broad immune response effects, including the induction of TH17/IL17A immunity, which impacts the development and homeostasis of host tissues. SFB colonized the gut, but not oral cavity, and increased IL17A levels in the ileum and serum. SFB had catabolic effects on alveolar bone and non-oral skeletal sites, which was attributed to enhanced osteoclastogenesis. The alveolar bone marrow of SFB vs. GF mice had increased dendritic cells, activated helper T-cells, TH1 cells, TH17 cells, and upregulated Tnf. Primary osteoblast cultures from SFB and GF mice were stimulated with vehicle-control, IL17A, or TNF to elucidate osteoblast-derived signaling factors contributing to the pro-osteoclastic phenotype in SFB mice. Treatment of RAW264.7 osteoclastic cells with supernatants from vehicle-stimulated SFB vs. GF osteoblasts recapitulated the osteoclast phenotype found in vivo. Supernatants from TNF-stimulated osteoblasts normalized RAW264.7 osteoclast endpoints across SFB and GF cultures, which was dependent on the induction of CXCL1 and CCL2. This report reveals that commensal gut microbes have the capacity to regulate osteoimmune processes in alveolar bone. Outcomes from this investigation challenge the current paradigm that alveolar bone health and homeostasis is strictly regulated by oral microbes.


Assuntos
Osso e Ossos , Osteoclastos , Animais , Bactérias , Homeostase , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Osteoclastos/metabolismo , Células Th17
9.
FASEB J ; 35(11): e22015, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34699641

RESUMO

Periodontitis-mediated alveolar bone loss is caused by dysbiotic shifts in the commensal oral microbiota that upregulate proinflammatory osteoimmune responses. The study purpose was to determine whether antimicrobial-induced disruption of the commensal microbiota has deleterious effects on alveolar bone. We administered an antibiotic cocktail, minocycline, or vehicle-control to sex-matched C57BL/6T mice from age 6- to 12 weeks. Antibiotic cocktail and minocycline had catabolic effects on alveolar bone in specific-pathogen-free (SPF) mice. We then administered minocycline or vehicle-control to male mice reared under SPF and germ-free conditions, and we subjected minocycline-treated SPF mice to chlorhexidine oral antiseptic rinses. Alveolar bone loss was greater in vehicle-treated SPF versus germ-free mice, demonstrating that the commensal microbiota drives naturally occurring alveolar bone loss. Minocycline- versus vehicle-treated germ-free mice had similar alveolar bone loss outcomes, implying that antimicrobial-driven alveolar bone loss is microbiota dependent. Minocycline induced phylum-level shifts in the oral bacteriome and exacerbated naturally occurring alveolar bone loss in SPF mice. Chlorhexidine further disrupted the oral bacteriome and worsened alveolar bone loss in minocycline-treated SPF mice, validating that antimicrobial-induced oral dysbiosis has deleterious effects on alveolar bone. Minocycline enhanced osteoclast size and interface with alveolar bone in SPF mice. Neutrophils and plasmacytoid dendritic cells were upregulated in cervical lymph nodes of minocycline-treated SPF mice. Paralleling the upregulated proinflammatory innate immune cells, minocycline therapy increased TH 1 and TH 17 cells that have known pro-osteoclastic actions in the alveolar bone. This report reveals that antimicrobial perturbation of the commensal microbiota induces a proinflammatory oral dysbiotic state that exacerbates naturally occurring alveolar bone loss.


Assuntos
Perda do Osso Alveolar/microbiologia , Antibacterianos/efeitos adversos , Disbiose/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Interações entre Hospedeiro e Microrganismos , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL
10.
J Fam Nurs ; 27(4): 304-326, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33855890

RESUMO

Transgender and gender diverse (TGD) children face increased behavioral health risks including suicidal behaviors and substance abuse. Parental affirmation is associated with behavioral health outcomes similar to non-TGD peers. This integrative review synthesizes and appraises evidence regarding experiences of parenting a TGD child in the United States or Canada from 2008 to 2018. Most parents across these 15 studies described affirming their child's gender at time of interview. Parents reported initial interpersonal processes (emotions, concerns, beliefs), sought education (frequently online), and described interactions with family members and professionals that were not always affirming. Parents accessed support groups but described their own well-being as a low priority relative to the child's needs. Parents' own needs for well-being may affect the process of parenting a TGD child and should be explored. Future research should address the experiences of non-parent family members and participants from more diverse backgrounds. Nursing education must consistently address gender affirming care.


Assuntos
Transtornos Relacionados ao Uso de Substâncias , Pessoas Transgênero , Criança , Identidade de Gênero , Humanos , Poder Familiar , Pais , Estados Unidos
11.
JBMR Plus ; 4(3): e10338, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32161843

RESUMO

The commensal gut microbiota critically regulates immunomodulatory processes that influence normal skeletal growth and maturation. However, the influence of specific microbes on commensal gut microbiota osteoimmunoregulatory actions is unknown. We have shown previously that the commensal gut microbiota enhances TH17/IL17A immune response effects in marrow and liver that have procatabolic/antianabolic actions in the skeleton. Segmented filamentous bacteria (SFB), a specific commensal gut bacterium within phylum Firmicutes, potently induces TH17/IL17A-mediated immunity. The study purpose was to delineate the influence of SFB on commensal gut microbiota immunomodulatory actions regulating normal postpubertal skeletal development. Two murine models were utilized: SFB-monoassociated mice versus germ-free (GF) mice and specific-pathogen-free (SPF) mice +/- SFB. SFB colonization was validated by 16S rDNA analysis, and SFB-induced TH17/IL17A immunity was confirmed by upregulation of Il17a in ileum and IL17A in serum. SFB-colonized mice had an osteopenic trabecular bone phenotype, which was attributed to SFB actions suppressing osteoblastogenesis and enhancing osteoclastogenesis. Intriguingly, SFB-colonized mice had increased expression of proinflammatory chemokines and acute-phase reactants in the liver. Lipocalin-2 (LCN2), an acute-phase reactant and antimicrobial peptide, was substantially elevated in the liver and serum of SFB-colonized mice, which supports the notion that SFB regulation of commensal gut microbiota osteoimmunomodulatory actions are mediated in part through a gut-liver-bone axis. Proinflammatory TH17 and TH1 cells were increased in liver-draining lymph nodes of SFB-colonized mice, which further substantiates that SFB osteoimmune-response effects may be mediated through the liver. SFB-induction of Il17a in the gut and Lcn2 in the liver resulted in increased circulating levels of IL17A and LCN2. Recognizing that IL17A and LCN2 support osteoclastogenesis/suppress osteoblastogenesis, SFB actions impairing postpubertal skeletal development appear to be mediated through immunomodulatory effects in both the gut and liver. This research reveals that specific microbes critically impact commensal gut microbiota immunomodulatory actions regulating normal postpubertal skeletal growth and maturation. © 2020 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

12.
Cell Rep ; 27(11): 3385-3400.e3, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31189119

RESUMO

Regulation of body temperature critically depends on thyroid hormone (TH). Recent studies revealed that TH induces browning of white adipose tissue, possibly contributing to the observed hyperthermia in hyperthyroid patients and potentially providing metabolic benefits. Here, we show that browning by TH requires TH-receptor ß and occurs independently of the sympathetic nervous system. The beige fat, however, lacks sufficient adrenergic stimulation and is not metabolically activated despite high levels of uncoupling protein 1 (UCP1). Studies at different environmental temperatures reveal that TH instead causes hyperthermia by actions in skeletal muscle combined with a central body temperature set-point elevation. Consequently, the metabolic and thermogenic effects of systemic hyperthyroidism were maintained in UCP1 knockout mice, demonstrating that neither beige nor brown fat contributes to the TH-induced hyperthermia and elevated glucose consumption, and underlining that the mere presence of UCP1 is insufficient to draw conclusions on the therapeutic potential of browning agents.


Assuntos
Tecido Adiposo Bege/metabolismo , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Glucose/metabolismo , Termogênese , Hormônios Tireóideos/metabolismo , Tecido Adiposo Bege/fisiologia , Tecido Adiposo Marrom/fisiologia , Tecido Adiposo Branco/fisiologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Receptores Adrenérgicos beta 3/metabolismo , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
13.
Endocrinology ; 158(6): 1977-1984, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28368510

RESUMO

3-Iodothyronamine (3-T1AM) is an endogenous thyroid hormone (TH)-derived metabolite that induces severe hypothermia in mice after systemic administration; however, the underlying mechanisms have remained enigmatic. We show here that the rapid 3-T1AM-induced loss in body temperature is a consequence of peripheral vasodilation and subsequent heat loss (e.g., over the tail surface). The condition is subsequently intensified by hypomotility and a lack of brown adipose tissue activation. Although the possible 3-T1AM targets trace amine-associated receptor 1 or α2a-adrenergic receptor were detected in tail artery and aorta respectively, myograph studies did not show any direct effect of 3-T1AM on vasodilation, suggesting that its actions are likely indirect. Intracerebroventricular application of 3-T1AM, however, replicated the phenotype of tail vasodilation and body temperature decline and led to neuronal activation in the hypothalamus, suggesting that the metabolite causes tail vasodilation through a hypothalamic signaling pathway. Consequently, the 3-T1AM response constitutes anapyrexia rather than hypothermia and closely resembles the heat-stress response mediated by hypothalamic temperature-sensitive neurons. Our results thus underline the well-known role of the hypothalamus as the body's thermostat and suggest an additional molecular link between TH signaling and the central control of body temperature.


Assuntos
Encéfalo/fisiologia , Cauda/irrigação sanguínea , Tironinas/farmacologia , Vasodilatação/efeitos dos fármacos , Animais , Regulação da Temperatura Corporal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Infusões Intraventriculares , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/efeitos dos fármacos , Cauda/efeitos dos fármacos , Tironinas/administração & dosagem
14.
Am J Physiol Endocrinol Metab ; 311(6): E901-E910, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27780820

RESUMO

Activation of brown adipose tissue (BAT) and browning of white adipose tissue (WAT) present potential new therapies for obesity and type 2 diabetes. Here, we examined the effects of ß3-adrenergic stimulation on tissue-specific uptake and storage of free fatty acids (FFA) and its implications for whole body FFA metabolism in diet-induced obese rats using a multi-radiotracer technique. Male Wistar rats were high fat-fed for 12 wk and administered ß3-agonist CL316,243 (CL, 1 mg·kg-1·day-1) or saline via osmotic minipumps during the last 3 wk. The rats were then fasted and acutely infused with a tracer mixture ([14C]palmitate and the partially metabolized R-[3H]bromopalmitate) under anesthesia. CL infusion decreased body weight gain and fasting plasma glucose levels. While core body temperature was unaffected, infrared thermography showed an increase in tail heat dissipation following CL infusion. Interestingly, CL markedly increased both FFA storage and utilization in interscapular and perirenal BAT, whereas the flux of FFA to skeletal muscle was decreased. In this rat model of obesity, only sporadic populations of beige adipocytes were detected in the epididymal WAT depot of CL-infused rats, and there was no change in FFA uptake or utilization in WAT following CL infusion. In summary, ß3-agonism robustly increased FFA flux to BAT coupled with enhanced utilization. Increased BAT activation most likely drove the increased tail heat dissipation to maintain thermostasis. Our results emphasize the quantitative role of brown fat as the functional target of ß3-agonism in obesity.


Assuntos
Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Branco/efeitos dos fármacos , Agonistas de Receptores Adrenérgicos beta 3/farmacologia , Dieta Hiperlipídica , Dioxóis/farmacologia , Ácidos Graxos não Esterificados/metabolismo , Obesidade/metabolismo , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Marrom/patologia , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/patologia , Animais , Western Blotting , Radioisótopos de Carbono , Imuno-Histoquímica , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Palmitatos/metabolismo , Ratos , Ratos Wistar , Receptores Adrenérgicos beta 3 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Termografia , Trítio , Proteína Desacopladora 1/efeitos dos fármacos , Proteína Desacopladora 1/metabolismo
15.
Open Forum Infect Dis ; 3(1): ofw043, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27011953

RESUMO

Background. UpToDate is an online clinical decision support resource that is used extensively by clinicians around the world. Digital surveillance techniques have shown promise to aid with the detection and monitoring of infectious disease outbreaks. We sought to determine whether UpToDate searches for Middle East respiratory syndrome (MERS) could be used to detect and monitor MERS outbreaks in Saudi Arabia. Methods. We analyzed daily searches related to MERS in Jeddah and Riyadh, Saudi Arabia during 3 outbreaks in these cities in 2014 and 2015 and compared them with reported cases during the same periods. We also compared UpToDate MERS searches in the affected cities to those in a composite of 4 negative control cities for the 2 outbreaks in 2014. Results. UpToDate MERS searches during all 3 MERS outbreaks in Saudi Arabia showed a correlation to reported cases. In addition, UpToDate MERS search volume in Jeddah and Riyadh during the outbreak periods in 2014 was significantly higher than the concurrent search volume in the 4 negative control cities. In contrast, during the baseline periods, there was no difference between UpToDate searches for MERS in the affected cities compared with the negative control cities. Conclusions. UpToDate search activity seems to be useful for detecting and monitoring outbreaks of MERS in Saudi Arabia.

16.
J Endocrinol ; 228(1): R19-29, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26450134

RESUMO

Obesity and its comorbidities are a growing problem worldwide. In consequence, several new strategies have been proposed to promote weight loss and improve insulin sensitivity. Recently, it has been demonstrated that certain populations of white adipocytes can be 'browned', i.e., recruited to a more brown-like adipocyte, capable of thermogenesis through increased expression of uncoupling protein 1. The list of browning agents that induce these so-called beige adipocytes is growing constantly. However, the underlying mechanisms are often poorly understood, with the possibility that some of these agents cause browning as a secondary effect. Moreover, it remains unclear whether beige adipocytes can contribute sufficiently to affect whole-body energy expenditure in a functionally significant manner. This review presents an overview of the different molecular pathways leading to the induction of beige fat, including direct stimulation and indirect actions on the CNS or the immune system. We discuss the available evidence on the capacity of beige adipocytes to influence whole-body energy expenditure in rodents, and lastly outline the potential problems of translating browning capacity into the potential treatment of human metabolic diseases.


Assuntos
Tecido Adiposo Marrom/fisiologia , Tecido Adiposo Branco/fisiologia , Animais , Diferenciação Celular , Diabetes Mellitus Tipo 2/prevenção & controle , Metabolismo Energético , Expressão Gênica , Humanos , Sistema Imunitário , Resistência à Insulina , Canais Iônicos/genética , Masculino , Camundongos , Proteínas Mitocondriais/genética , Obesidade/prevenção & controle , Roedores , Termogênese/efeitos dos fármacos , Proteína Desacopladora 1 , Redução de Peso
17.
Curr Biol ; 25(22): 2997-3003, 2015 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26549257

RESUMO

Hypothalamic tanycytes are considered to function as sensors of peripheral metabolism. To facilitate this role, they express a wide range of receptors, including fibroblast growth factor receptor 1 (FGFR1). Using a monoclonal antibody (IMC-H7) that selectively antagonizes the FGFR1c isoform, we investigated possible actions of FGFR1c in a natural animal model of adiposity, the Siberian hamster. Infusion of IMC-H7 into the third ventricle suppressed appetite and increased energy expenditure. Likewise, peripheral treatment with IMC-H7 decreased appetite and body weight and increased energy expenditure and fat oxidation. A greater reduction in body weight and caloric intake was observed in response to IMC-H7 during the long-day fat state as compared to the short-day lean state. This enhanced response to IMC-H7 was also observed in calorically restricted hamsters maintained in long days, suggesting that it is the central photoperiodic state rather than the peripheral adiposity that determines the response to FGFR1c antagonism. Hypothalamic thyroid hormone availability is controlled by deiodinase enzymes (DIO2 and DIO3) expressed in tanycytes and is the key regulator of seasonal cycles of energy balance. Therefore, we determined the effect of IMC-H7 on hypothalamic expression of these deiodinase enzymes. The reductions in food intake and body weight were always associated with decreased expression of DIO2 in the hypothalamic ependymal cell layer containing tanycytes. These data provide further support for the notion the tanycytes are an important component of the mechanism by which the hypothalamus integrates central and peripheral signals to regulate energy intake and expenditure.


Assuntos
Anticorpos Monoclonais/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Adiposidade/fisiologia , Animais , Anticorpos Monoclonais/imunologia , Ritmo Circadiano/fisiologia , Cricetinae , Hipotálamo/metabolismo , Masculino , Modelos Animais , Phodopus , Fotoperíodo , Isoformas de Proteínas/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/imunologia , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Magreza/metabolismo , Hormônios Tireóideos/metabolismo , Redução de Peso/efeitos dos fármacos
18.
Mol Cell Endocrinol ; 416: 19-26, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26319697

RESUMO

Thyroid hormone is a well-known regulator of brain, lung and kidney development and function. However, the molecular mechanisms by which the hormone exerts its function have remained largely enigmatic, and only a limited set of target genes have been identified in these tissues. Using a mouse model with a mutation in thyroid hormone receptor α1 (TRα1), we here demonstrate that the expression of carbonic anhydrase 4 in lung and brain of the adult animal depends on intact TRα1 signaling. In the kidney, carbonic anhydrase 4 mRNA and protein are not affected by the mutant TRα1, but are acutely repressed by thyroid hormone. However, neither lung function--as measured by respiration rate and oxygen saturation--nor urine pH levels were affected by altered carbonic anhydrase 4 levels, suggesting that other carbonic anhydrases are likely to compensate. Taken together, our findings identify a previously unknown marker of TRα1 action in brain and lung, and provide a novel negatively regulated target gene to assess renal thyroid hormone status.


Assuntos
Encéfalo/metabolismo , Anidrase Carbônica IV/metabolismo , Rim/metabolismo , Pulmão/metabolismo , Receptores alfa dos Hormônios Tireóideos/metabolismo , Tri-Iodotironina/metabolismo , Animais , Heterozigoto , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Mutação , Taxa Respiratória , Receptores alfa dos Hormônios Tireóideos/genética
19.
Public Health Rep ; 130(2): 153-60, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25729104

RESUMO

OBJECTIVES: Industry and occupation variables are overlooked in many public health surveillance efforts, yet they are useful for describing the burden and distribution of various public health diseases, behaviors, and conditions. This study is the first ever analysis of the Colorado Behavioral Risk Factor Surveillance System (BRFSS) to describe chronic conditions and risk behaviors by occupation. It is intended to provide a new perspective on this existing data source and demonstrate the value of occupation as a core demographic variable for public health research, policy, and practice. METHODS: Two standardized employment questions were included in the 2012 Colorado BRFSS survey and administered to eligible survey respondents who were employed, self-employed, or out of work for less than one year. Occupation data were coded using the National Institute for Occupational Safety and Health (NIOSH) Industry and Occupation Computerized Coding System. We analyzed health behaviors and conditions by major occupation groups. We calculated prevalence estimates and 95% confidence intervals (CIs). RESULTS: The prevalence of chronic conditions, health statuses, and risk behaviors (e.g., smoking and seatbelt use) varied significantly by occupation. For example, compared with all workers (93.6%, 95% CI 92.7, 94.5), significantly fewer workers in farming, forestry, fishing and construction, extraction jobs (87.0%, 95% CI 82.0, 92.0) reported always or nearly always wearing a seatbelt while driving. Additionally, significantly more office and administrative support workers (27.5%, 95% CI 22.5, 32.4) compared with all workers (20.6%, 95% CI 19.3, 22.0) were obese. Further observation and research is needed to understand the effects of occupation on health outcomes and behaviors. CONCLUSION: There are no other Colorado state-level datasets that link health behaviors and chronic conditions with occupation. This study shows that the prevalence of chronic conditions and risk behaviors varies substantially by occupation. Other states conducting the BRFSS may choose to adopt the NIOSH industry and occupation module and add other questions to further investigate health issues by occupation.


Assuntos
Sistema de Vigilância de Fator de Risco Comportamental , Doença Crônica/epidemiologia , Nível de Saúde , Indústrias/estatística & dados numéricos , Ocupações/estatística & dados numéricos , Vigilância em Saúde Pública , Adulto , Colorado/epidemiologia , Conjuntos de Dados como Assunto , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade , Assunção de Riscos
20.
Br J Pharmacol ; 172(13): 3426-33, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25765843

RESUMO

BACKGROUND AND PURPOSE: 3-Iodothyronamine (3-T1 AM) is an endogenous thyroid hormone derivative reported to induce strong hypothermia and bradycardia within minutes upon injection in rodents. Although 3-T1 AM is rapidly converted to several other metabolites in vivo, these strong pharmacological responses were solely attributed to 3-T1 AM, leaving potential contributions of downstream products untested. We therefore examined the cardiometabolic effects of 3-iodothyroacetic acid (TA1 ), the main degradation product of 3-T1 AM. EXPERIMENTAL APPROACH: We used a sensitive implantable radiotelemetry system in C57/Bl6J mice to study the effects of TA1 on body temperature and heart rate, as well as other metabolic parameters. KEY RESULTS: Interestingly, despite using pharmacological TA1 doses, we observed no effects on heart rate or body temperature after a single TA1 injection (50 mg·kg(-1) , i.p.) compared to sham-injected controls. Repeated administration of TA1 (5 mg·kg(-1) , i.p. for 7 days) likewise did not alter body weight, food and water intake, heart rate, blood pressure, brown adipose tissue (BAT) thermogenesis or body temperature. Moreover, mRNA expression of tissue specific genes in heart, kidney, liver, BAT and lung was also not altered by TA1 compared to sham-injected controls. CONCLUSIONS AND IMPLICATIONS: Our data therefore conclusively demonstrate that TA1 does not contribute to the cardiovascular or thermoregulatory effects observed after 3-T1 AM administration in mice, suggesting that the oxidative deamination constitutes an important deactivation mechanism for 3-T1 AM with possible implications for cardiovascular and thermoregulatory functions.


Assuntos
Tironinas/farmacologia , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Animais , Pressão Sanguínea/efeitos dos fármacos , Temperatura Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , RNA Mensageiro/metabolismo , Tiroxina/sangue , Transcriptoma/efeitos dos fármacos , Tri-Iodotironina/sangue
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...