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1.
J Orthop Translat ; 35: 99-112, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36262374

RESUMEN

Background: Metabolic disruption commonly follows Anterior Cruciate Ligament Reconstruction (ACLR) surgery. Brief exposure to low amplitude and frequency pulsed electromagnetic fields (PEMFs) has been shown to promote in vitro and in vivo murine myogeneses via the activation of a calcium-mitochondrial axis conferring systemic metabolic adaptations. This randomized-controlled pilot trial sought to detect local changes in muscle structure and function using MRI, and systemic changes in metabolism using plasma biomarker analyses resulting from ACLR, with or without accompanying PEMF therapy. Methods: 20 patients requiring ACLR were randomized into two groups either undergoing PEMF or sham exposure for 16 weeks following surgery. The operated thighs of 10 patients were exposed weekly to PEMFs (1 â€‹mT for 10 â€‹min) for 4 months following surgery. Another 10 patients were subjected to sham exposure and served as controls to allow assessment of the metabolic repercussions of ACLR and PEMF therapy. Blood samples were collected prior to surgery and at 16 weeks for plasma analyses. Magnetic resonance data were acquired at 1 and 16 weeks post-surgery using a Siemens 3T Tim Trio system. Phosphorus (31P) Magnetic Resonance Spectroscopy (MRS) was utilized to monitor changes in high-energy phosphate metabolism (inorganic phosphate (Pi), adenosine triphosphate (ATP) and phosphocreatine (PCr)) as well as markers of membrane synthesis and breakdown (phosphomonoesters (PME) and phosphodiester (PDE)). Quantitative Magnetization Transfer (qMT) imaging was used to elucidate changes in the underlying tissue structure, with T1-weighted and 2-point Dixon imaging used to calculate muscle volumes and muscle fat content. Results: Improvements in markers of high-energy phosphate metabolism including reductions in ΔPi/ATP, Pi/PCr and (Pi â€‹+ â€‹PCr)/ATP, and membrane kinetics, including reductions in PDE/ATP were detected in the PEMF-treated cohort relative to the control cohort at study termination. These were associated with reductions in the plasma levels of certain ceramides and lysophosphatidylcholine species. The plasma levels of biomarkers predictive of muscle regeneration and degeneration, including osteopontin and TNNT1, respectively, were improved, whilst changes in follistatin failed to achieve statistical significance. Liquid chromatography with tandem mass spectrometry revealed reductions in small molecule biomarkers of metabolic disruption, including cysteine, homocysteine, and methionine in the PEMF-treated cohort relative to the control cohort at study termination. Differences in measurements of force, muscle and fat volumes did not achieve statistical significance between the cohorts after 16 weeks post-ACLR. Conclusion: The detected changes suggest improvements in systemic metabolism in the post-surgical PEMF-treated cohort that accords with previous preclinical murine studies. PEMF-based therapies may potentially serve as a manner to ameliorate post-surgery metabolic disruptions and warrant future examination in more adequately powered clinical trials. The Translational Potential of this Article: Some degree of physical immobilisation must inevitably follow orthopaedic surgical intervention. The clinical paradox of such a scenario is that the regenerative potential of the muscle mitochondrial pool is silenced. The unmet need was hence a manner to maintain mitochondrial activation when movement is restricted and without producing potentially damaging mechanical stress. PEMF-based therapies may satisfy the requirement of non-invasively activating the requisite mitochondrial respiration when mobility is restricted for improved metabolic and regenerative recovery.

2.
FASEB J ; 33(11): 12853-12872, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31518158

RESUMEN

We show that both supplemental and ambient magnetic fields modulate myogenesis. A lone 10 min exposure of myoblasts to 1.5 mT amplitude supplemental pulsed magnetic fields (PEMFs) accentuated in vitro myogenesis by stimulating transient receptor potential (TRP)-C1-mediated calcium entry and downstream nuclear factor of activated T cells (NFAT)-transcriptional and P300/CBP-associated factor (PCAF)-epigenetic cascades, whereas depriving myoblasts of ambient magnetic fields slowed myogenesis, reduced TRPC1 expression, and silenced NFAT-transcriptional and PCAF-epigenetic cascades. The expression levels of peroxisome proliferator-activated receptor γ coactivator 1α, the master regulator of mitochondriogenesis, was also enhanced by brief PEMF exposure. Accordingly, mitochondriogenesis and respiratory capacity were both enhanced with PEMF exposure, paralleling TRPC1 expression and pharmacological sensitivity. Clustered regularly interspaced short palindromic repeats-Cas9 knockdown of TRPC1 precluded proliferative and mitochondrial responses to supplemental PEMFs, whereas small interfering RNA gene silencing of TRPM7 did not, coinciding with data that magnetoreception did not coincide with the expression or function of other TRP channels. The aminoglycoside antibiotics antagonized and down-regulated TRPC1 expression and, when applied concomitantly with PEMF exposure, attenuated PEMF-stimulated calcium entry, mitochondrial respiration, proliferation, differentiation, and epigenetic directive in myoblasts, elucidating why the developmental potential of magnetic fields may have previously escaped detection. Mitochondrial-based survival adaptations were also activated upon PEMF stimulation. Magnetism thus deploys an authentic myogenic directive that relies on an interplay between mitochondria and TRPC1 to reach fruition.-Yap, J. L. Y., Tai, Y. K., Fröhlich, J., Fong, C. H. H., Yin, J. N., Foo, Z. L., Ramanan, S., Beyer, C., Toh, S. J., Casarosa, M., Bharathy, N., Kala, M. P., Egli, M., Taneja, R., Lee, C. N., Franco-Obregón, A. Ambient and supplemental magnetic fields promote myogenesis via a TRPC1-mitochondrial axis: evidence of a magnetic mitohormetic mechanism.


Asunto(s)
Campos Magnéticos , Mitocondrias Musculares/metabolismo , Desarrollo de Músculos , Mioblastos Esqueléticos/metabolismo , Transducción de Señal , Canales Catiónicos TRPC/metabolismo , Animales , Línea Celular , Ratones , Mitocondrias Musculares/genética , Mioblastos Esqueléticos/citología , Canales Catiónicos TRPC/genética
3.
Br J Neurosurg ; 30(5): 549-53, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27080311

RESUMEN

INTRODUCTION: Balloon angioplasty and/or selective intra-arterial vasodilator therapies are treatment options in patients with vasospasm after subarachnoid hemorrhage (SAH). We analyzed the effect of balloon angioplasty and/or selective intra-arterial vasodilator therapy in our patients. METHODS: Twenty-six patients (vasodilation group, VDT) were treated with intra-arterial nimodipine. The balloon angioplasty with nimodiopine-group (BAP-N group) comprised 21 patients. The primary endpoint of this study was successful angiographic vessel dilation in vasospastic vessels after balloon angioplasty, together with nimodipine (BAP-N group), compared to intra-arterial vasodilator therapy (VDT group) with nimodipine alone. RESULTS: A significant effect of angioplasty plus nimodipine was found in the central arteries (composite endpoint) with an OR of 2.4 (95% CI: 1.4-4.2], p = 0.002), indicating a chance of improvement of the BAP-N group of more than twice compared to nimodipine infusions alone. Significant advantages for BAP-N-therapy were also encountered in the internal carotid artery (OR 5.4, p < 0.001) and basilar artery (OR 29.7, p = 0.003). A joint analysis of all arteries combined failed to show significant benefit of BAP-N therapy (OR 1.5, p = 0.079), which was also true for cerebral peripheral arteries (OR 0.77, p = 0.367). There was no difference in clinical outcome between both groups. CONCLUSIONS: In SAH patients with vasospasm, a combination therapy of balloon angioplasty and intra-arterial nimodipine resulted in a more than doubled vasodilative effect in the central cerebral arteries compared to the sole infusion of nimodipine. Regarding the ICA and BA arteries, this beneficial effect was even more pronounced. Although there was a tendency of better effects of the BAP-N group, regarding the overall effect in all territories combined, this failed to reach statistical evidence. In cerebral peripheral arteries, no differences were observed, and there was no difference in clinical outcome, too.


Asunto(s)
Procedimientos Endovasculares/métodos , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/cirugía , Vasoespasmo Intracraneal/etiología , Vasoespasmo Intracraneal/cirugía , Adulto , Anciano , Angioplastia de Balón , Arterias Cerebrales/diagnóstico por imagen , Arterias Cerebrales/cirugía , Procedimientos Endovasculares/efectos adversos , Femenino , Humanos , Inyecciones Intraarteriales , Masculino , Persona de Mediana Edad , Nimodipina/administración & dosificación , Nimodipina/uso terapéutico , Seguridad del Paciente , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Resultado del Tratamiento , Vasodilatadores/administración & dosificación , Vasodilatadores/uso terapéutico
4.
Ann Rheum Dis ; 75(5): 883-90, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-25858641

RESUMEN

BACKGROUND: Nintedanib is a tyrosine kinase inhibitor that has recently been shown to slow disease progression in idiopathic pulmonary fibrosis in two replicate phase III clinical trials. The aim of this study was to analyse the antifibrotic effects of nintedanib in preclinical models of systemic sclerosis (SSc) and to provide a scientific background for clinical trials in SSc. METHODS: The effects of nintedanib on migration, proliferation, myofibroblast differentiation and release of extracellular matrix of dermal fibroblasts were analysed by microtitre tetrazolium and scratch assays, stress fibre staining, qPCR and SirCol assays. The antifibrotic effects of nintedanib were evaluated in bleomycin-induced skin fibrosis, in a murine sclerodermatous chronic graft-versus-host disease model and in tight-skin-1 mice. RESULTS: Nintedanib dose-dependently reduced platelet-derived growth factor-induced and transforming growth factor-ß-induced proliferation and migration as well as myofibroblast differentiation and collagen release of dermal fibroblasts from patients with and healthy individuals. Nintedanib also inhibited the endogenous activation of SSc fibroblasts. Nintedanib prevented bleomycin-induced skin fibrosis in a dose-dependent manner and was also effective in the treatment of established fibrosis. Moreover, treatment with nintedanib ameliorated fibrosis in the chronic graft-versus-host disease model and in tight-skin-1 mice in well-tolerated doses. CONCLUSIONS: We demonstrate that nintedanib effectively inhibits the endogenous as well as cytokine-induced activation of SSc fibroblasts and exerts potent antifibrotic effects in different complementary mouse models of SSc. These data have direct translational implications for clinical trials with nintedanib in SSc.


Asunto(s)
Fibroblastos/efectos de los fármacos , Indoles/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico , Esclerodermia Sistémica/tratamiento farmacológico , Animales , Bleomicina , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos/métodos , Femenino , Fibroblastos/patología , Fibroblastos/fisiología , Fibrosis , Enfermedad Injerto contra Huésped/prevención & control , Humanos , Indoles/administración & dosificación , Indoles/farmacología , Masculino , Ratones Endogámicos BALB C , Ratones Mutantes , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/farmacología , Esclerodermia Sistémica/patología , Piel/efectos de los fármacos , Piel/patología
5.
PLoS One ; 8(9): e72944, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24039828

RESUMEN

INTRODUCTION: A common drawback of many anticancer therapies is non-specificity in action of killing. We investigated the potential of ultra-low intensity and frequency pulsed electromagnetic fields (PEMFs) to kill breast cancer cells. Our criteria to accept this technology as a potentially valid therapeutic approach were: 1) cytotoxicity to breast cancer cells and; 2) that the designed fields proved innocuous to healthy cell classes that would be exposed to the PEMFs during clinical treatment. METHODS: MCF7 breast cancer cells and their normal counterparts, MCF10 cells, were exposed to PEMFs and cytotoxic indices measured in order to design PEMF paradigms that best kill breast cancer cells. The PEMF parameters tested were: 1) frequencies ranging from 20 to 50 Hz; 2) intensities ranging from 2 mT to 5 mT and; 3) exposure durations ranging from 30 to 90 minutes per day for up to three days to determine the optimum parameters for selective cancer cell killing. RESULTS: We observed a discrete window of vulnerability of MCF7 cells to PEMFs of 20 Hz frequency, 3 mT magnitude and exposure duration of 60 minutes per day. The cell damage accrued in response to PEMFs increased with time and gained significance after three days of consecutive daily exposure. By contrast, the PEMFs parameters determined to be most cytotoxic to breast cancer MCF-7 cells were not damaging to normal MCF-10 cells. CONCLUSION: Based on our data it appears that PEMF-based anticancer strategies may represent a new therapeutic approach to treat breast cancer without affecting normal tissues in a manner that is non-invasive and can be potentially combined with existing anti-cancer treatments.


Asunto(s)
Campos Electromagnéticos , Apoptosis/genética , Apoptosis/efectos de la radiación , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/terapia , Línea Celular Tumoral , Supervivencia Celular/efectos de la radiación , Roturas del ADN/efectos de la radiación , Campos Electromagnéticos/efectos adversos , Femenino , Citometría de Flujo , Humanos , Células MCF-7 , Magnetoterapia , Factores de Tiempo
6.
Best Pract Res Clin Rheumatol ; 24(4): 489-96, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20732647

RESUMEN

The spectrum of arthritis ranges from erosive (e.g., rheumatoid arthritis) to ossifying disease with formation of new bone (e.g., ankylosing spondylitis and osteoarthritis). The molecular basis for these different patterns of arthritis had long been unclear. In the last few years, however, characterisation of catabolic and anabolic molecular pathways in different forms of arthritis led to a better understanding of joint remodelling and revealed novel therapeutic targets. Recent findings show that catabolic and anabolic molecular pathways govern bone and cartilage remodelling in healthy and arthritic joints. The predominance of catabolic molecular pathways (e.g., receptor activator of nuclear factor-kappaB ligand (RANKL)/RANK and cathepsin K) causes erosive disease whereas anabolic signalling (e.g., Wnt and fibroblast growth factor (FGF)18) favours the formation of new bone including bony spurs and subchondral sclerosis. Other pathways may have a dual function in arthritis (e.g., hedgehog) leading to either catabolic or anabolic joint remodelling dependent on other factors. Key mediators within these signalling pathways may serve as novel targets for treating pathological remodelling of bone and cartilage in arthritis. Molecular pathways govern remodelling processes of bone and cartilage in arthritic joints. Future therapies will likely target the pathologic activity of these molecular pathways to specifically block either catabolic or anabolic joint remodelling in arthritis.


Asunto(s)
Antirreumáticos/uso terapéutico , Artritis/tratamiento farmacológico , Remodelación Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Cartílago Articular/efectos de los fármacos , Proteínas Adaptadoras Transductoras de Señales , Artritis/metabolismo , Proteínas Morfogenéticas Óseas/antagonistas & inhibidores , Proteínas Morfogenéticas Óseas/metabolismo , Remodelación Ósea/fisiología , Huesos/metabolismo , Cartílago Articular/metabolismo , Catepsina K/antagonistas & inhibidores , Catepsina K/metabolismo , Ensayos Clínicos como Asunto , Factores de Crecimiento de Fibroblastos/antagonistas & inhibidores , Factores de Crecimiento de Fibroblastos/metabolismo , Marcadores Genéticos , Proteínas Hedgehog/antagonistas & inhibidores , Proteínas Hedgehog/metabolismo , Humanos , Ligando RANK/antagonistas & inhibidores , Ligando RANK/metabolismo , Transducción de Señal/efectos de los fármacos , Proteínas Wnt/antagonistas & inhibidores , Proteínas Wnt/metabolismo
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