RESUMO
Acetaminophen (ACE) is a widely used analgesic and antipyretic drug with various applications, from pain relief to fever reduction. Recent studies have reported equivocal effects of habitual ACE intake on exercise performance, muscle growth, and risks to bone health. Thus, this study aimed to assess the impact of a 6-week, low-dose ACE regimen on muscle and bone adaptations in exercising and non-exercising rats. Nine-week-old Wistar rats (n = 40) were randomized to an exercise or control (no exercise) condition with ACE or without (placebo). For the exercise condition, rats ran 5 days per week for 6 weeks at a 5% incline for 2 min at 15 cm/s, 2 min at 20 cm/s, and 26 min at 25 cm/s. A human equivalent dose of ACE was administered (379 mg/kg body weight) in drinking water and adjusted each week based on body weight. Food, water intake, and body weight were measured daily. At the beginning of week 6, animals in the exercise group completed a maximal treadmill test. At the end of week 6, rats were euthanized, and muscle cross-sectional area (CSA), fiber type, and signaling pathways were measured. Additionally, three-point bending and microcomputer tomography were measured in the femur. Follow-up experiments in human primary muscle cells were used to explore supra-physiological effects of ACE. Data were analyzed using a two-way ANOVA for treatment (ACE or placebo) and condition (exercise or non-exercise) for all animal outcomes. Data for cell culture experiments were analyzed via ANOVA. If omnibus significance was found in either ANOVA, a post hoc analysis was completed, and a Tukey's adjustment was used. ACE did not alter body weight, water intake, food intake, or treadmill performance (p > .05). There was a treatment-by-condition effect for Young's Modulus where placebo exercise was significantly lower than placebo control (p < .05). There was no treatment by condition effects for microCT measures, muscle CSA, fiber type, or mRNA expression. Phosphorylated-AMPK was significantly increased with exercise (p < .05) and this was attenuated with ACE treatment. Furthermore, phospho-4EBP1 was depressed in the exercise group compared to the control (p < .05) and increased in the ACE control and ACE exercise group compared to placebo exercise (p < .05). A low dose of ACE did not influence chronic musculoskeletal adaptations in exercising rodents but acutely attenuated AMPK phosphorylation and 4EBP1 dephosphorylation post-exercise.
Assuntos
Acetaminofen , Condicionamento Físico Animal , Animais , Humanos , Ratos , Acetaminofen/farmacologia , Proteínas Quinases Ativadas por AMP/metabolismo , Peso Corporal , Carboidratos , Músculo Esquelético/metabolismo , Condicionamento Físico Animal/fisiologia , Ratos WistarRESUMO
Although the functions of the peripheral nervous system in whole body homeostasis and sensation have been understood for many years, recent investigation has uncovered new roles for innervation in the musculoskeletal system. This review centers on advances regarding the function of nerves in the development and repair of two connected tissues: tendon and bone. Innervation in healthy tendons is generally confined to the tendon sheaths, and tendon-bone attachment units are typically aneural. In contrast to tendon, bone is an innervated and vascularized structure. Historically, the function of abundant peripheral nerves in bone has been limited to pain and some non-painful sensory perception in disease and injury. Indeed, much of our understanding of peripheral nerves in tendons, bones, and entheses is limited to the source and type of innervation in healthy and injured tissues. However, more recent studies have made important observations regarding the appearance, type, and innervation patterns of nerves during embryonic and postnatal development and in response to injury, which suggest a more expansive role for peripheral nerves in the formation of musculoskeletal tissues. Indeed, tendons and bones develop in a close spatiotemporal relationship in the embryonic mesoderm. Models of limb denervation have shed light on the importance of sensory innervation in bone and to a lesser extent, tendon development, and more recent work has unraveled key nerve signaling pathways. Furthermore, loss of sensory innervation also impairs healing of bone fractures and may contribute to chronic tendinopathy. However, more study is required to translate our knowledge of peripheral nerves to therapeutic strategies to combat bone and tendon diseases.
Assuntos
Osso e Ossos , Tendões , Homeostase , Nervos Periféricos , Tendões/inervaçãoRESUMO
OBJECTIVES: Prior studies noted that chondrocyte SIRT6 activity is repressed in older chondrocytes rendering cells susceptible to catabolic signalling events implicated in osteoarthritis (OA). This study aimed to define the effect of Sirt6 deficiency on the development of post-traumatic and age-associated OA in mice. METHODS: Male cartilage-specific Sirt6-deficient mice and Sirt6 intact controls underwent destabilisation of the medial meniscus (DMM) or sham surgery at 16 weeks of age and OA severity was analysed at 6 and 10 weeks postsurgery. Age-associated OA was assessed in mice aged 12 and 18 months of age. OA severity was analysed by micro-CT, histomorphometry and scoring of articular cartilage structure, toluidine blue staining and osteophyte formation. SIRT6-regulated pathways were analysed in human chondrocytes by RNA-sequencing, qRT-PCR and immunoblotting. RESULTS: Sirt6-deficient mice displayed enhanced DMM-induced OA severity and accelerated age-associated OA when compared with controls, characterised by increased cartilage damage, osteophyte formation and subchondral bone sclerosis. In chondrocytes, RNA-sequencing revealed that SIRT6 depletion significantly repressed cartilage extracellular matrix (eg, COL2A1) and anabolic growth factor (eg, insulin-like growth factor-1 (IGF-1)) gene expression. Gain-of-function and loss-of-function studies in chondrocytes demonstrated that SIRT6 depletion attenuated, whereas adenoviral overexpression or MDL-800-induced SIRT6 activation promoted IGF-1 signalling by increasing Aktser473 phosphorylation. CONCLUSIONS: SIRT6 deficiency increases post-traumatic and age-associated OA severity in vivo. SIRT6 profoundly regulated the pro-anabolic and pro-survival IGF-1/Akt signalling pathway and suggests that preserving the SIRT6/IGF-1/Akt axis may be necessary to protect cartilage from injury-associated or age-associated OA. Targeted therapies aimed at increasing SIRT6 function could represent a novel strategy to slow or stop OA.
Assuntos
Cartilagem Articular , Osteoartrite , Osteófito , Sirtuínas , Masculino , Animais , Camundongos , Humanos , Idoso , Fator de Crescimento Insulin-Like I/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Osteoartrite/genética , Osteoartrite/metabolismo , Condrócitos/metabolismo , Cartilagem Articular/metabolismo , RNA/metabolismo , Sirtuínas/genética , Sirtuínas/metabolismo , Modelos Animais de DoençasRESUMO
The membrane protein ANKH was known to prevent pathological mineralization of joints and was thought to export pyrophosphate (PPi) from cells. This did not explain, however, the presence of ANKH in tissues, such as brain, blood vessels and muscle. We now report that in cultured cells ANKH exports ATP, rather than PPi, and, unexpectedly, also citrate as a prominent metabolite. The extracellular ATP is rapidly converted into PPi, explaining the role of ANKH in preventing ankylosis. Mice lacking functional Ank (Ankank/ank mice) had plasma citrate concentrations that were 65% lower than those detected in wild type control animals. Consequently, citrate excretion via the urine was substantially reduced in Ankank/ank mice. Citrate was even undetectable in the urine of a human patient lacking functional ANKH. The hydroxyapatite of Ankank/ank mice contained dramatically reduced levels of both, citrate and PPi and displayed diminished strength. Our results show that ANKH is a critical contributor to extracellular citrate and PPi homeostasis and profoundly affects bone matrix composition and, consequently, bone quality.
Assuntos
Osso e Ossos/metabolismo , Calcinose/genética , Ácido Cítrico/metabolismo , Proteínas de Transporte de Fosfato/genética , Trifosfato de Adenosina/metabolismo , Animais , Desenvolvimento Ósseo/genética , Calcinose/metabolismo , Calcinose/patologia , Diferenciação Celular , Células Cultivadas , Difosfatos/metabolismo , Humanos , Fenômenos Mecânicos , Camundongos , Mutação/genética , Proteínas de Transporte de Fosfato/metabolismoRESUMO
Suboptimal adherence to maintenance therapy contributes to poor asthma control and exacerbations. This study evaluated the effect of different elements of a connected inhaler system (CIS), comprising clip-on inhaler sensors, a patient-facing app and a healthcare professional (HCP) dashboard, on adherence to asthma maintenance therapy.This was an open-label, parallel-group, 6-month, randomised controlled trial in adults with uncontrolled asthma (asthma control test (ACT) score less than 20) on fixed-dose inhaled corticosteroids/long-acting ß-agonist maintenance therapy (n=437). All subjects received fluticasone furoate/vilanterol ELLIPTA dry-powder inhalers for maintenance and salbutamol/albuterol metered-dose inhalers for rescue, with a sensor attached to each inhaler. Participants were randomised to one of five CIS study arms (allocation ratio 1:1:1:1:1) reflecting the recipient of the data feedback from the sensors, as follows: 1) maintenance use to participants and HCPs (n=87); 2) maintenance use to participants (n=88); 3) maintenance and rescue use to participants and HCPs (n=88); 4) maintenance and rescue use to participants (n=88); and 5) no feedback (control) (n=86).For the primary endpoint, observed mean±sd adherence to maintenance therapy over months 4-6 was 82.2±16.58% (n=83) in the "maintenance to participants and HCPs" arm and 70.8±27.30% (n=85) in the control arm. The adjusted least squares mean±se was 80.9±3.19% and 69.0±3.19%, respectively (study arm difference: 12.0%, 95% CI 5.2-18.8%; p<0.001). Adherence was also significantly greater in the other CIS arms versus the control arm. The mean percentage of rescue medication free days (months 4-6) was significantly greater in participants receiving data on their rescue use compared with controls. ACT scores improved in all study arms with no significant differences between groups.A CIS can improve adherence to maintenance medication and reduce rescue medication use in patients with uncontrolled asthma.
Assuntos
Antiasmáticos , Asma , Administração por Inalação , Adulto , Albuterol/uso terapêutico , Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Broncodilatadores/uso terapêutico , Combinação de Medicamentos , Humanos , Adesão à Medicação , Nebulizadores e VaporizadoresRESUMO
The activation of the Wnt/ß-catenin signaling pathway is critical for skeletal development but surprisingly little is known about the requirements for the specific frizzled (Fzd) receptors that recognize Wnt ligands. To define the contributions of individual Fzd proteins to osteoblast function, we profiled the expression of all 10 mammalian receptors during calvarial osteoblast differentiation. Expression of Fzd4 was highly upregulated during in vitro differentiation and therefore targeted for further study. Mice lacking Fzd4 in mature osteoblasts had normal cortical bone structure but reduced cortical tissue mineral density and also exhibited an impairment in the femoral trabecular bone acquisition that was secondary to a defect in the mineralization process. Consistent with this observation, matrix mineralization, markers of osteoblastic differentiation, and the ability of Wnt3a to stimulate the accumulation of ß-catenin were reduced in cultures of calvarial osteoblasts deficient for Fzd4. Interestingly, Fzd4-deficient osteoblasts exhibited an increase in the expression of Fzd8 both in vitro and in vivo, which suggests that the two receptors may exhibit overlapping functions. Indeed, ablating a single Fzd8 allele in osteoblast-specific Fzd4 mutants produced a more severe effect on bone acquisition. Taken together, our data indicate that Fzd4 is required for normal bone development and mineralization despite compensation from Fzd8.
Assuntos
Receptores Frizzled/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Osso e Ossos/metabolismo , Osso e Ossos/fisiologia , Diferenciação Celular/fisiologia , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/metabolismo , Osteogênese/fisiologia , Regulação para Cima/fisiologia , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/fisiologiaRESUMO
Sensory nerves emanating from the dorsal root extensively innervate the surfaces of mammalian bone, a privileged location for the regulation of biomechanical signaling. Here, we show that NGF-TrkA signaling in skeletal sensory nerves is an early response to mechanical loading of bone and is required to achieve maximal load-induced bone formation. First, the elimination of TrkA signaling in mice harboring mutant TrkAF592A alleles was found to greatly attenuate load-induced bone formation induced by axial forelimb compression. Next, both in vivo mechanical loading and in vitro mechanical stretch were shown to induce the profound up-regulation of NGF in osteoblasts within 1 h of loading. Furthermore, inhibition of TrkA signaling following axial forelimb compression was observed to reduce measures of Wnt/ß-catenin activity in osteocytes in the loaded bone. Finally, the administration of exogenous NGF to wild-type mice was found to significantly increase load-induced bone formation and Wnt/ß-catenin activity in osteocytes. In summary, these findings demonstrate that communication between osteoblasts and sensory nerves through NGF-TrkA signaling is essential for load-induced bone formation in mice.
Assuntos
Músculo Esquelético/metabolismo , Fator de Crescimento Neural/metabolismo , Osteogênese/fisiologia , Receptor trkA/metabolismo , Células Receptoras Sensoriais/metabolismo , Via de Sinalização Wnt/fisiologia , Animais , Camundongos , Camundongos Mutantes , Fator de Crescimento Neural/genética , Osteoblastos/metabolismo , Receptor trkA/genética , Suporte de Carga/fisiologiaRESUMO
Sclerostin has traditionally been thought of as a local inhibitor of bone acquisition that antagonizes the profound osteoanabolic capacity of activated Wnt/ß-catenin signaling, but serum sclerostin levels in humans exhibit a correlation with impairments in several metabolic parameters. These data, together with the increased production of sclerostin in mouse models of type 2 diabetes, suggest an endocrine function. To determine whether sclerostin contributes to the coordination of whole-body metabolism, we examined body composition, glucose homeostasis, and fatty acid metabolism in Sost-/- mice as well as mice that overproduce sclerostin as a result of adeno-associated virus expression from the liver. Here, we show that in addition to dramatic increases in bone volume, Sost-/- mice exhibit a reduction in adipose tissue accumulation in association with increased insulin sensitivity. Sclerostin overproduction results in the opposite metabolic phenotype due to adipocyte hypertrophy. Additionally, Sost-/- mice and those administered a sclerostin-neutralizing antibody are resistant to obesogenic diet-induced disturbances in metabolism. This effect appears to be the result of sclerostin's effects on Wnt signaling and metabolism in white adipose tissue. Since adipocytes do not produce sclerostin, these findings suggest an unexplored endocrine function for sclerostin that facilitates communication between the skeleton and adipose tissue.
Assuntos
Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Composição Corporal , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Glicoproteínas/metabolismo , Via de Sinalização Wnt , Proteínas Adaptadoras de Transdução de Sinal , Adipócitos/patologia , Tecido Adiposo/patologia , Animais , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Glicoproteínas/genética , Peptídeos e Proteínas de Sinalização Intercelular , Camundongos , Camundongos KnockoutRESUMO
In skeletal tissue, loss or mutation of the gap junction protein connexin 43 (Cx43, also known as GJA1) in cells of the osteoblast lineage leads to a profound cortical bone phenotype and defective tissue remodeling. There is mounting evidence in bone cells that the C-terminus (CT) of Cx43 is a docking platform for signaling effectors and is required for efficient downstream signaling. Here, we examined this function, using a mouse model of Cx43 CT-truncation (Gja1 K258Stop). Relative to Gja1+/- controls, male Gja1-/K258Stop mice have a cortical bone phenotype that is remarkably similar to those reported for deletion of the entire Cx43 gene in osteoblasts. Furthermore, we show that the Cx43 CT binds several signaling proteins that are required for optimal osteoblast function, including PKCδ, ERK1 and ERK2 (ERK1/2, also known as MAPK3 and MAPK1, respectively) and ß-catenin. Deletion of the Cx43 CT domain affects these signaling cascades, impacting osteoblast proliferation, differentiation, and collagen processing and organization. These data imply that, at least in bone, Cx43 gap junctions not only exchange signals, but also recruit the appropriate effector molecules to the Cx43 CT in order to efficiently activate signaling cascades that affect cell function and bone acquisition.
Assuntos
Remodelação Óssea , Conexina 43/química , Conexina 43/metabolismo , Osteoblastos/metabolismo , Osteogênese , Transdução de Sinais , Animais , Reabsorção Óssea/patologia , Calcificação Fisiológica , Diferenciação Celular , Proliferação de Células , Colágeno/metabolismo , Osso Cortical/metabolismo , Matriz Extracelular/metabolismo , Masculino , Camundongos , Modelos Animais , Fenótipo , Porosidade , Ligação Proteica , Domínios Proteicos , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
PURPOSE: To summarize currently available data regarding the use of bone marrow aspirate concentrate (BMAC) for the treatment of focal chondral lesions of the knee in experimental animal models and human clinical studies. METHODS: A systematic review searching for the terms "(bone marrow)" AND "(aspirate OR concentrate)" AND "(cartilage OR chondral OR osteochondral)" was performed in the databases PubMed, Cochrane Central Register of Controlled Trials, and Google Scholar regarding the use of BMAC for the treatment of focal chondral lesions of the knee. The inclusion criteria were animal and clinical studies published in English that used autologous BMAC to treat focal chondral defects of the knee. We excluded studies that evaluated nonconcentrated preparations of bone marrow aspirate or preparations that were culture expanded. RESULTS: A total of 23 studies were included: 10 studies performed in animal models and 13 human clinical studies. Animal studies showed inconsistent outcomes regarding the efficacy of BMAC for the treatment of chondral or osteochondral lesions, assessed by gross morphology, second-look arthroscopy, magnetic resonance imaging, histology, immunohistochemistry, mechanical testing, and micro-tomography. Chondral defect filling was achieved with fibrocartilage or "hyaline-like" cartilage. Cells present in BMAC did not meet the criteria to be characterized as mesenchymal stem cells according to the International Society for Cell Therapy because freshly isolated cells failed to show tri-lineage differentiation. Overall, all clinical studies, independent of the study group or level of evidence, reported improved clinical outcomes and higher macroscopic, magnetic resonance imaging, and histology scores. Comparative trials favored BMAC over microfracture and reported equivalent outcomes between BMAC and matrix-induced autologous chondrocyte implantation. However, clinical studies were scant and showed low scientific rigor, poor methodologic quality, and low levels of evidence on average. CONCLUSIONS: Although clinical success in short-term and midterm applications has been suggested for the application of BMAC for the restoration of cartilage defects in lesions of the knee, current study designs are generally of low scientific rigor. In addition, clinical applications of this technology in animal model investigations have shown inconsistent outcomes. Thus, clinicians should apply this technology cautiously. LEVEL OF EVIDENCE: Level IV, systematic review of Level II, III, and IV evidence studies.
Assuntos
Transplante de Medula Óssea/métodos , Doenças das Cartilagens/terapia , Traumatismos do Joelho/terapia , Animais , Artroscopia , Cartilagem Articular/lesões , Modelos Animais de Doenças , Humanos , Cartilagem Hialina/transplante , Imageamento por Ressonância Magnética/métodos , Cirurgia de Second-Look/estatística & dados numéricosRESUMO
Bone and skeletal muscle mass are highly correlated in mammals, suggesting the existence of common anabolic signaling networks that coordinate the development of these two anatomically adjacent tissues. The activin signaling pathway is an attractive candidate to fulfill such a role. Here, we generated mice with conditional deletion of activin receptor (ACVR) type 2A, ACVR2B, or both, in osteoblasts, to determine the contribution of activin receptor signaling in regulating bone mass. Immunohistochemistry localized ACVR2A and ACVR2B to osteoblasts and osteocytes. Primary osteoblasts expressed activin signaling components, including ACVR2A, ACVR2B, and ACVR1B (ALK4) and demonstrated increased levels of phosphorylated Smad2/3 upon exposure to activin ligands. Osteoblasts lacking ACVR2B did not show significant changes in vitro However, osteoblasts deficient in ACVR2A exhibited enhanced differentiation indicated by alkaline phosphatase activity, mineral deposition, and transcriptional expression of osterix, osteocalcin, and dentin matrix acidic phosphoprotein 1. To investigate activin signaling in osteoblasts in vivo, we analyzed the skeletal phenotypes of mice lacking these receptors in osteoblasts and osteocytes (osteocalcin-Cre). Similar to the lack of effect in vitro, ACVR2B-deficient mice demonstrated no significant change in any bone parameter. By contrast, mice lacking ACVR2A had significantly increased femoral trabecular bone volume at 6 weeks of age. Moreover, mutant mice lacking both ACVR2A and ACVR2B demonstrated sustained increases in trabecular bone volume, similar to those in ACVR2A single mutants, at 6 and 12 weeks of age. Taken together, these results indicate that activin receptor signaling, predominantly through ACVR2A, directly and negatively regulates bone mass in osteoblasts.
Assuntos
Receptores de Activinas Tipo II/metabolismo , Osteoblastos/metabolismo , Osteócitos/metabolismo , Osteogênese , Receptores de Activinas Tipo II/química , Receptores de Activinas Tipo II/genética , Animais , Animais Recém-Nascidos , Desenvolvimento Ósseo , Proliferação de Células , Células Cultivadas , Cruzamentos Genéticos , Feminino , Fêmur , Deleção de Genes , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Desenvolvimento Muscular , Músculo Esquelético/citologia , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Mutação , Especificidade de Órgãos , Osteoblastos/citologia , Osteócitos/citologia , CrânioRESUMO
Fluticasone furoate and fluticasone propionate are recommended options for prophylactic maintenance treatment of persistent asthma. Using data from two previous clinical studies (GSK studies: FFA109685/NCT00603278, FFA112059/NCT01159912), this meta-analysis compared change from baseline in clinic visit mean trough forced expiratory volume in 1 s (FEV1) with fluticasone furoate 100 µg once-daily (FF100) versus fluticasone propionate 250 µg twice-daily (FP250) in adolescents and adults with persistent asthma. Using a DerSimonian-Laird random-effects model (primary meta-analysis), there was no statistically significant difference between FF100 and FP250 in change from baseline in trough FEV1 (-1.7 mL [95% CI -80.4, +77.0], p = 0.9664) and FF100 was non-inferior to FP250. Supporting analyses using least squares mean and fixed-effects model approaches produced similar findings. In this analysis, FF100 and FP250 demonstrated a comparable treatment effect on trough FEV1 in patients aged ≥12 years with persistent asthma; however, results interpretation should consider study design and methodological limitations.
Assuntos
Androstadienos/administração & dosagem , Asma/tratamento farmacológico , Broncodilatadores/administração & dosagem , Fluticasona/administração & dosagem , Administração por Inalação , Adolescente , Adulto , Asma/fisiopatologia , Esquema de Medicação , Volume Expiratório Forçado , Humanos , Resultado do TratamentoRESUMO
Medication-related osteonecrosis of the jaw (MRONJ) is a rare, but devastating condition caused by bisphosphonates, receptor activator of nuclear factor kappa-B ligand inhibitors, anti-angiogenic medications, and disease-modifying antirheumatic drugs. While the clinical spectrum of MRONJ has a wide range, there is a subgroup of patients that do not improve with antibiotics and conservative surgical debridement resulting in pathologic fractures, draining fistulas, and/or osteomyelitis. For the severely affected individuals, the only cure is surgical resection with micro-vascular free flap reconstruction. The etiology of MRONJ is unknown because of the lack of understanding of the biological underpinnings of the disorder connected to the mechanisms of action of the various medications. This limited knowledge has resulted in the classification of patients by clinical presentation rather than underlying pathology. Therefore, the aim of this article is to present a mechanistic framework of MRONJ through the mevalonate pathway in the context of the medications that are known to induce it and explore potential novel therapeutics.
RESUMO
Digital measures of health status captured during daily life could greatly augment current in-clinic assessments for rheumatoid arthritis (RA), to enable better assessment of disease progression and impact. This work presents results from weaRAble-PRO, a 14-day observational study, which aimed to investigate how digital health technologies (DHT), such as smartphones and wearables, could augment patient reported outcomes (PRO) to determine RA status and severity in a study of 30 moderate-to-severe RA patients, compared to 30 matched healthy controls (HC). Sensor-based measures of health status, mobility, dexterity, fatigue, and other RA specific symptoms were extracted from daily iPhone guided tests (GT), as well as actigraphy and heart rate sensor data, which was passively recorded from patients' Apple smartwatch continuously over the study duration. We subsequently developed a machine learning (ML) framework to distinguish RA status and to estimate RA severity. It was found that daily wearable sensor-outcomes robustly distinguished RA from HC participants (F1, 0.807). Furthermore, by day 7 of the study (half-way), a sufficient volume of data had been collected to reliably capture the characteristics of RA participants. In addition, we observed that the detection of RA severity levels could be improved by augmenting standard patient reported outcomes with sensor-based features (F1, 0.833) in comparison to using PRO assessments alone (F1, 0.759), and that the combination of modalities could reliability measure continuous RA severity, as determined by the clinician-assessed RAPID-3 score at baseline (r2, 0.692; RMSE, 1.33). The ability to measure the impact of the disease during daily life-through objective and remote digital outcomes-paves the way forward to enable the development of more patient-centric and personalised measurements for use in RA clinical trials.
RESUMO
In mature bone, NGF is produced by osteoblasts following mechanical loading and signals through resident sensory nerves expressing its high affinity receptor, neurotrophic tyrosine kinase receptor type 1 (TrkA), to support bone formation. Here, we investigated whether osteoblastic expression of Toll-like receptor 4 (TLR4), a key receptor in the NF-κB signaling pathway, is required to initiate NGF-TrkA signaling required for load-induced bone formation. Although Tlr4 conditional knockout mice have normal skeletal mass and strength in adulthood, the loss of TLR4 signaling significantly reduced lamellar bone formation following loading. Inhibition of TLR4 signaling reduced Ngf expression in primary osteoblasts and RNA sequencing of bones from Tlr4 conditional knockout mice and wild-type littermates revealed dysregulated inflammatory signaling three days after osteogenic mechanical loading. In total, our study reveals an important role for osteoblastic TLR4 in the skeletal adaptation of bone to mechanical forces.
RESUMO
Bioprinting facilitates the generation of complex, three-dimensional (3D), cell-based constructs for various applications. Although multiple bioprinting technologies have been developed, extrusion-based systems have become the dominant technology due to the diversity of materials (bioinks) that can be utilized, either individually or in combination. However, each bioink has unique material properties and extrusion characteristics that affect bioprinting utility, accuracy, and precision. Here, we have extended our previous work to achieve high precision (i.e. repeatability) and printability across samples by optimizing bioink-specific printing parameters. Specifically, we hypothesized that a fuzzy inference system (FIS) could be used as a computational method to address the imprecision in 3D bioprinting test data and uncover the optimal printing parameters for a specific bioink that result in high accuracy and precision. To test this hypothesis, we have implemented a FIS model consisting of four inputs (bioink concentration, printing flow rate, speed, and temperature) and two outputs to quantify the precision (scaffold bioprinted linewidth variance) and printability. We validate our use of the bioprinting precision index with both standard and normalized printability factors. Finally, we utilize optimized printing parameters to bioprint scaffolds containing up to 30 × 106cells ml-1with high printability and precision. In total, our results indicate that computational methods are a cost-efficient measure to improve the precision and robustness of extrusion 3D bioprinting.
Assuntos
Bioimpressão , Impressão Tridimensional , Tecnologia , Bioimpressão/métodos , Engenharia Tecidual , Alicerces TeciduaisRESUMO
Rheumatoid arthritis (RA) is a fluctuating progressive disease requiring frequent symptom assessment for appropriate management. Continuous tracking using digital technologies may provide greater insights of a patient's experience. This prospective study assessed the feasibility, reliability, and clinical utility of using novel digital technologies to remotely monitor participants with RA. Participants with moderate to severe RA and non-RA controls were monitored continuously for 14 days using an iPhone with an integrated bespoke application and an Apple Watch. Participants completed patient-reported outcome measures and objective guided tests designed to assess disease-related impact on physical function. The study was completed by 28 participants with RA, 28 matched controls, and 2 unmatched controls. Completion rates for all assessments were > 97% and were reproducible over time. Several guided tests distinguished between RA and control cohorts (e.g., mean lie-to-stand time [seconds]: RA: 4.77, control: 3.25; P < 0.001). Participants with RA reporting greater stiffness, pain, and fatigue had worse guided test performances (e.g., wrist movement [P < 0.001] and sit-to-stand transition time [P = 0.009]) compared with those reporting lower stiffness, pain, and fatigue. This study demonstrates that digital technologies can be used in a well-controlled, remote clinical setting to assess the daily impact of RA.
Assuntos
Artrite Reumatoide , Aplicativos Móveis , Humanos , Estudos Prospectivos , Reprodutibilidade dos Testes , Artrite Reumatoide/diagnóstico , Dor , Fadiga/diagnóstico , Assistência Centrada no PacienteRESUMO
Chronic low back pain is a highly prevalent health condition intricately linked to intervertebral disc degeneration. One of the prominent features of disc degeneration that is commonly observed with aging is dystrophic calcification. ATP-binding cassette sub-family C member 6 (ABCC6), a presumed ATP efflux transporter, is a key regulator of systemic levels of the mineralization inhibitor pyrophosphate (PPi). Mutations in ABCC6 result in pseudoxanthoma elasticum (PXE), a progressive human metabolic disorder characterized by mineralization of the skin and elastic tissues. The implications of ABCC6 loss-of-function on pathological mineralization of structures in the spine, however, are unknown. Using the Abcc6 -/- mouse model of PXE, we investigated age-dependent changes in the vertebral bone and intervertebral disc. Abcc6 -/- mice exhibited diminished trabecular bone quality parameters at 7 months, which remained significantly lower than the wild-type mice at 18 months of age. Abcc6 -/- vertebrae showed increased TRAP staining along with decreased TNAP staining, suggesting an enhanced bone resorption as well as decreased bone formation. Surprisingly, however, loss of ABCC6 resulted only in a mild, aging disc phenotype without evidence of dystrophic mineralization. Finally, we tested the utility of oral K3Citrate to treat the vertebral phenotype since it is shown to regulate hydroxyapatite mechanical behavior. The treatment resulted in inhibition of the osteoclastic response and an early improvement in mechanical properties of the bone underscoring the promise of potassium citrate as a therapeutic agent. Our data suggest that although ectopic mineralization is tightly regulated in the disc, loss of ABCC6 compromises vertebral bone quality and dysregulates osteoblast-osteoclast coupling.
RESUMO
Background: Telemedicine may help the detection of symptom worsening in patients with chronic obstructive pulmonary disease (COPD), potentially resulting in improved outcomes. This study aimed to determine the feasibility and acceptability of telemedicine among patients with COPD and physicians and facility staff in Japan. Methods: This was a 52-week multicenter, prospective, single-arm, feasibility and acceptability cohort study of Japanese patients ≥40 years of age with COPD or asthma-COPD overlap. Participants underwent training to use YaDoc, a telemedicine smartphone App, which included seven daily symptom questions and weekly COPD Assessment Test (CAT) questions. The primary endpoint was participant compliance for required question completion. The secondary endpoint was participant and physician/facility staff acceptability of YaDoc based on questionnaires completed at Week 52. The impact of the Japanese COVID-19 pandemic state of emergency on results was also assessed. Results: Of the 84 participants enrolled (mean age: 68.7 years, 88% male), 72 participants completed the study. Completion was high in the first six months but fell after that. Median (interquartile range [IQR]) compliance for daily questionnaire entry was 66.6% (31.0-91.8) and 81.0% (45.3-94.3) for weekly CAT entry. Positive participant responses to the exit questionnaire were highest regarding YaDoc ease of use (83.8%), positive impact on managing health (58.8%), and overall satisfaction (53.8%). Of the 26 physicians and facility staff enrolled, 24 completed the study. Of these, the majority (66.7%) responded positively regarding app facilitation of communication between physicians and participants to manage disease. Compliance was similar before and after the first COVID-19 state of emergency in Japan. Conclusion: Daily telemedicine monitoring is potentially feasible and acceptable to both patients and physicians in the management of COPD. These results may inform potential use of telemedicine in clinical practice and design of future studies. Clinical Trial Registration: JapicCTI-194916.
Assuntos
COVID-19 , Doença Pulmonar Obstrutiva Crônica , Telemedicina , Humanos , Masculino , Feminino , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/terapia , Estudos de Coortes , Estudos de Viabilidade , Estudos Prospectivos , Pandemias , COVID-19/diagnóstico , COVID-19/epidemiologia , Telemedicina/métodosRESUMO
Dupuytren's disease is a benign fibroproliferative disorder of the hand that results in disabling digital contractures that impair function and diminish the quality of life. The incidence of this disease has been correlated with chronic inflammatory states, but any direct association between inflammatory cytokines and Dupuytren's disease is not known. We hypothesized that advanced fibroproliferation is associated with increased levels of circulating inflammatory cytokines. Blood and fibrotic cord tissue were collected preoperatively from patients with severe contracture and control patients. Blood plasma concentrations of known inflammatory cytokines were evaluated using a multiplex immunoassay. Proteins from the cord tissue were analyzed by RNA sequencing and immunohistochemistry. Moreover, collagen-rich cords were analyzed using Fourier-transform infrared spectroscopy. The results indicate that patients exhibited significantly elevated circulating inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin (IL)-2, and IL-12p70, as compared with controls. Similarly, IL-4 and IL-13 were detected significantly more frequently in Dupuytren's disease as compared with control. RNA sequencing revealed 5311 differentially expressed genes and distinct clustering between diseased and control samples. In addition to increased expression of genes associated with fibroproliferation, we also observed upregulation of transcripts activated by inflammatory cytokines, including prolactin inducible protein and keratin intermediate filaments. IL-2, but not TNF-α, was detected in fibrotic cord tissue by immunohistochemistry. Finally, spectroscopic assays revealed a significant reduction of the collagen content and alterations of collagen cross-linking within the Dupuytren's disease tissues. In total, our results illustrate that patients with severe Dupuytren's disease exhibit substantially elevated circulating inflammatory cytokines that may drive fibroproliferation. Clinical Significance: The results from this study establish the basis for a specific cytokine profile that may be useful for diagnostic testing and therapeutic intervention in Dupuytren's disease.