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1.
Nature ; 619(7968): 143-150, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37380764

RESUMO

Caloric restriction that promotes weight loss is an effective strategy for treating non-alcoholic fatty liver disease and improving insulin sensitivity in people with type 2 diabetes1. Despite its effectiveness, in most individuals, weight loss is usually not maintained partly due to physiological adaptations that suppress energy expenditure, a process known as adaptive thermogenesis, the mechanistic underpinnings of which are unclear2,3. Treatment of rodents fed a high-fat diet with recombinant growth differentiating factor 15 (GDF15) reduces obesity and improves glycaemic control through glial-cell-derived neurotrophic factor family receptor α-like (GFRAL)-dependent suppression of food intake4-7. Here we find that, in addition to suppressing appetite, GDF15 counteracts compensatory reductions in energy expenditure, eliciting greater weight loss and reductions in non-alcoholic fatty liver disease (NAFLD) compared to caloric restriction alone. This effect of GDF15 to maintain energy expenditure during calorie restriction requires a GFRAL-ß-adrenergic-dependent signalling axis that increases fatty acid oxidation and calcium futile cycling in the skeletal muscle of mice. These data indicate that therapeutic targeting of the GDF15-GFRAL pathway may be useful for maintaining energy expenditure in skeletal muscle during caloric restriction.


Assuntos
Metabolismo Energético , Fator 15 de Diferenciação de Crescimento , Músculo Esquelético , Redução de Peso , Animais , Humanos , Camundongos , Depressores do Apetite/metabolismo , Depressores do Apetite/farmacologia , Depressores do Apetite/uso terapêutico , Restrição Calórica , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica , Ingestão de Alimentos/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Fator 15 de Diferenciação de Crescimento/metabolismo , Fator 15 de Diferenciação de Crescimento/farmacologia , Fator 15 de Diferenciação de Crescimento/uso terapêutico , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/terapia , Receptores Adrenérgicos beta/metabolismo , Redução de Peso/efeitos dos fármacos
2.
Toxins (Basel) ; 14(2)2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-35202132

RESUMO

Botulinum neurotoxin (BoNT) is commonly used to manage focal spasticity in stroke survivors. This study aimed to a perform comprehensive assessment of the effects of BoNT injection. Twelve stroke subjects with spastic hemiplegia (age: 52.0 ± 10.1 year; 5 females) received 100 units of BoNT to the spastic biceps brachii muscles. Clinical, biomechanical, electrophysiological, and neuro-motor assessments were performed one week (wk) before (pre-injection), 3 weeks (wks) after, and 3 months (mons) after BoNT injection. BoNT injection significantly reduced spasticity, muscle strength, reflex torque, and compound muscle action potential (CMAP) amplitude of spastic elbow flexors (all p < 0.05) during the 3-wks visit, and these values return to the pre-injection level during the 3-mons visit. Furthermore, the degree of reflex torque change was negatively correlated to the amount of non-reflex component of elbow flexor resistance torque. However, voluntary force control and non-reflex resistance torque remained unchanged throughout. Our results revealed parallel changes in clinical, neurophysiological and biomechanical assessment after BoNT injection; BoNT injection would be more effective if hypertonia was mainly mediated by underlying neural mechanisms. BoNT did not affect voluntary force control of spastic muscles.


Assuntos
Toxinas Botulínicas/administração & dosagem , Hemiplegia/tratamento farmacológico , Espasticidade Muscular/tratamento farmacológico , Fármacos Neuromusculares/administração & dosagem , Acidente Vascular Cerebral/tratamento farmacológico , Potenciais de Ação/efeitos dos fármacos , Adulto , Fenômenos Biomecânicos , Doença Crônica , Estudos Transversais , Cotovelo , Feminino , Hemiplegia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/etiologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Reflexo/efeitos dos fármacos , Acidente Vascular Cerebral/complicações , Sobreviventes , Torque
3.
Toxins (Basel) ; 13(5)2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922855

RESUMO

Botulinum toxin type A (BoNT-A) represents a first-line treatment for spasticity, a common disabling consequence of many neurological diseases. Electrical stimulation of motor nerve endings has been reported to boost the effect of BoNT-A. To date, a wide range of stimulation protocols has been proposed in the literature. We conducted a systematic review of current literature on the protocols of electrical stimulation to boost the effect of BoNT-A injection in patients with spasticity. A systematic search using the MeSH terms "electric stimulation", "muscle spasticity" and "botulinum toxins" and strings "electric stimulation [mh] OR electrical stimulation AND muscle spasticity [mh] OR spasticity AND botulinum toxins [mh] OR botulinum toxin type A" was conducted on PubMed, Scopus, PEDro and Cochrane library electronic databases. Full-text articles written in English and published from database inception to March 2021 were included. Data on patient characteristics, electrical stimulation protocols and outcome measures were collected. This systematic review provides a complete overview of current literature on the role of electrical stimulation to boost the effect of BoNT-A injection for spasticity, together with a critical discussion on its rationale based on the neurobiology of BoNT-A uptake.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Terapia por Estimulação Elétrica , Espasticidade Muscular/tratamento farmacológico , Adulto , Toxinas Botulínicas/uso terapêutico , Criança , Terapia Combinada , Terapia por Estimulação Elétrica/métodos , Humanos , Músculo Esquelético/efeitos dos fármacos , Resultado do Tratamento
4.
Life Sci ; 279: 119482, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33891939

RESUMO

AIM: Fibrosis is the most common complication from chronic diseases, and yet no therapy capable of mitigating its effects is available. Our goal is to unveil specific signaling regulating the fibrogenic process and to identify potential small molecule candidates that block fibrogenic differentiation of fibro/adipogenic progenitors. METHOD: We performed a large-scale drug screen using muscle-resident fibro/adipogenic progenitors from a mouse model expressing EGFP under the Collagen1a1 promotor. We first confirmed that the EGFP was expressed in response to TGFß1 stimulation in vitro. Then we treated cells with TGFß1 alone or with drugs from two libraries of known compounds. The drugs ability to block the fibrogenic differentiation was quantified by imaging and flow cytometry. From a two-rounds screening, positive hits were tested in vivo in the mice model for the Duchenne Muscular Dystrophy (mdx mice). The histopathology of the muscles was assessed with picrosirius red (fibrosis) and laminin staining (myofiber size). KEY FINDINGS: From the in vitro drug screening, we identified 21 drugs and tested 3 in vivo on the mdx mice. None of the three drugs significantly improved muscle histopathology. SIGNIFICANCE: The in vitro drug screen identified various efficient compounds, none of them strongly inhibited fibrosis in skeletal muscle of mdx mice. To explain these observations, we hypothesize that in Duchenne Muscular Dystrophy, in which fibrosis is a secondary event due to chronic degeneration and inflammation, the drugs tested could have adverse effect on regeneration or inflammation, balancing off any positive effects and leading to the absence of significant results.


Assuntos
Adipogenia , Fibrose/patologia , Músculo Esquelético/patologia , Distrofia Muscular de Duchenne/fisiopatologia , Preparações Farmacêuticas/administração & dosagem , Fator de Crescimento Transformador beta1/administração & dosagem , Animais , Diferenciação Celular , Feminino , Fibrose/tratamento farmacológico , Fibrose/etiologia , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos mdx , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo
5.
FASEB J ; 34(11): 15480-15491, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32969079

RESUMO

Thyroid hormones are important for homeostatic control of energy metabolism and body temperature. Although skeletal muscle is considered a key site for thyroid action, the contribution of thyroid hormone receptor signaling in muscle to whole-body energy metabolism and body temperature has not been resolved. Here, we show that T3-induced increase in energy expenditure requires thyroid hormone receptor alpha 1 (TRα1 ) in skeletal muscle, but that T3-mediated elevation in body temperature is achieved in the absence of muscle-TRα1 . In slow-twitch soleus muscle, loss-of-function of TRα1 (TRαHSACre ) alters the fiber-type composition toward a more oxidative phenotype. The change in fiber-type composition, however, does not influence the running capacity or motivation to run. RNA-sequencing of soleus muscle from WT mice and TRαHSACre mice revealed differentiated transcriptional regulation of genes associated with muscle thermogenesis, such as sarcolipin and UCP3, providing molecular clues pertaining to the mechanistic underpinnings of TRα1 -linked control of whole-body metabolic rate. Together, this work establishes a fundamental role for skeletal muscle in T3-stimulated increase in whole-body energy expenditure.


Assuntos
Metabolismo Energético/efeitos dos fármacos , Fibras Musculares de Contração Rápida/fisiologia , Fibras Musculares de Contração Lenta/fisiologia , Músculo Esquelético/fisiologia , Receptores alfa dos Hormônios Tireóideos/fisiologia , Hormônios Tireóideos/farmacologia , Animais , Masculino , Camundongos , Camundongos Knockout , Fibras Musculares de Contração Rápida/citologia , Fibras Musculares de Contração Rápida/efeitos dos fármacos , Fibras Musculares de Contração Lenta/citologia , Fibras Musculares de Contração Lenta/efeitos dos fármacos , Músculo Esquelético/citologia , Músculo Esquelético/efeitos dos fármacos , Condicionamento Físico Animal , Transcriptoma
6.
Int J Mol Sci ; 21(15)2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32752280

RESUMO

Goat's milk is a rich source of bioactive compounds (peptides, conjugated linoleic acid, short chain fatty acids, monounsaturated and polyunsaturated fatty acids, polyphenols such as phytoestrogens and minerals among others) that exert important health benefits. However, goat's milk composition depends on the type of food provided to the animal and thus, the abundance of bioactive compounds in milk depends on the dietary sources of the goat feed. The metabolic impact of goat milk rich in bioactive compounds during metabolic challenges such as a high-fat (HF) diet has not been explored. Thus, we evaluated the effect of milk from goats fed a conventional diet, a conventional diet supplemented with 30% Acacia farnesiana (AF) pods or grazing on metabolic alterations in mice fed a HF diet. Interestingly, the incorporation of goat's milk in the diet decreased body weight and body fat mass, improved glucose tolerance, prevented adipose tissue hypertrophy and hepatic steatosis in mice fed a HF diet. These effects were associated with an increase in energy expenditure, augmented oxidative fibers in skeletal muscle, and reduced inflammatory markers. Consequently, goat's milk can be considered a non-pharmacologic strategy to improve the metabolic alterations induced by a HF diet. Using the body surface area normalization method gave a conversion equivalent daily human intake dose of 1.4 to 2.8 glasses (250 mL per glass/day) of fresh goat milk for an adult of 60 kg, which can be used as reference for future clinical studies.


Assuntos
Metabolismo Energético/efeitos dos fármacos , Ácidos Graxos/administração & dosagem , Fígado Gorduroso/prevenção & controle , Leite/química , Mitocôndrias Musculares/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Obesidade/prevenção & controle , Animais , Biomarcadores/análise , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais , Fígado Gorduroso/etiologia , Expressão Gênica/efeitos dos fármacos , Cabras , Resistência à Insulina , Ácidos Linoleicos Conjugados/administração & dosagem , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Obesidade/etiologia
7.
Arch Environ Contam Toxicol ; 78(4): 555-567, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32008049

RESUMO

Use of pesticides continues to be indiscriminate, and birds are one of the worst affected non-targeted organisms. Information on the ill effects of pesticides on birds far from desired in India. Despite the presence of a wide variety and number of birds, there is exceedingly little data on organochlorine pesticide (OCP) residues in colonial nesting birds in sanctuaries of India. A total of 76 individuals belonging to 14 species of birds found dead between March 2008 and March 2010 were analyzed for pesticide residues in various tissues. Of all the OCPs analyzed, concentration of HCH was found to be the highest. Magnitude of contamination varied widely among species. Accumulation pattern of OCPs in colonial nesting birds was in the order ∑HCH > ∑endosulfan > ∑DDT > heptachlor epoxide > dieldrin. Pesticides, namely p,p-DDE and ß-HCH contributed most towards the total OCPs. Concentrations of DDT and its metabolites, HCH and isomers, dieldrin, and heptachlor epoxide were lower than the concentrations reported for various species of birds elsewhere in India. Although the sanctuaries presently studied have official boundaries, physical demarcations are missing and there are no proper earthen dykes particularly in Vedanthangal and Koonthankulam Bird Sanctuaries. During monsoon, runoff not only floods the Sanctuaries but also the cultivated areas nearby. Run off brings in residues of pesticides and fertilizers from the agricultural lands into the sanctuaries. Although OCP results in this study were below threshold limits, it may be noted that the long duration exposure even to low levels of pesticides could create a significant impact at population level. Hence, earthen dykes need to be built to avoid agricultural runoff entering the Sanctuary and also help to hold sufficient amount of water for breeding birds.


Assuntos
Aves/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/análise , Resíduos de Praguicidas/análise , Animais , Aves/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cruzamento , Índia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo
8.
Prostate Cancer Prostatic Dis ; 23(2): 309-315, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31745255

RESUMO

PURPOSE: To assess the prevalence of sarcopenia and whether body composition parameters are associated with disease progression and overall survival (OS) in castration-resistant prostate cancer (CRPC) patients. MATERIALS AND METHODS: This single-centre retrospective study evaluated data of 186 consecutive patients who underwent chemohormonal therapy between 2005 and 2016 as first-line systemic treatment for CRPC. Skeletal muscle and fat indices were determined using computerized tomography data before initiation of chemotherapy. Sarcopenia was defined as SMI of <55 cm2/m2. Visceral-to-subcutaneous fat ratio and skeletal muscle volume were calculated with body composition specific areas. Harrell's concordance index was used for predictive accuracy. RESULTS: A total of 154 (82.8%) patients met the criteria for sarcopenia; 139 (74.7%) individuals completed at least six cycles of docetaxel. Within a median follow-up of 24.1 months, age (HR 1.03, 95% CI 1.01-1.06, p = 0.02), high PSA (1.55, 95% CI 1.07-2.25, p = 0.02) and low skeletal muscle volume (HR 1.61, 95% CI 1.10-2.35, p = 0.02) were the only independent prognostic factor for tumor progression. Overall, 93 (50%) patients died during the follow-up period. The established prognosticator, the prechemotherapy presence of liver metastases (HR 1.32, 95% CI 1.08-1.61, p < 0.01) was associated with shorter OS. Moreover, we noted that patients with an elevated visceral-to-subcutaneous fat ratio tended to have a shorter OS (p = 0.06). CONCLUSION: The large majority of men with CRPC suffers from sarcopenia. In our cohort, low skeletal muscle volume was an independent adverse prognosticator for progression of disease. We could not detect a statistically significant body composition parameter for OS, although patients with a high proportion of visceral fat had a trend for shorter OS. However, we suggest that body composition parameters determined by CT data can provide useful objective prognostic factors that may support tailored treatment decision-making.


Assuntos
Antineoplásicos/efeitos adversos , Composição Corporal , Docetaxel/efeitos adversos , Músculo Esquelético/patologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Sarcopenia/patologia , Idoso , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/efeitos dos fármacos , Prognóstico , Neoplasias de Próstata Resistentes à Castração/patologia , Estudos Retrospectivos , Sarcopenia/induzido quimicamente , Taxa de Sobrevida
9.
Am J Physiol Heart Circ Physiol ; 318(2): H301-H325, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31886718

RESUMO

The introduction of duplex Doppler ultrasound almost half a century ago signified a revolutionary advance in the ability to assess limb blood flow in humans. It is now widely used to assess blood flow under a variety of experimental conditions to study skeletal muscle resistance vessel function. Despite its pervasive adoption, there is substantial variability between studies in relation to experimental protocols, procedures for data analysis, and interpretation of findings. This guideline results from a collegial discussion among physiologists and pharmacologists, with the goal of providing general as well as specific recommendations regarding the conduct of human studies involving Doppler ultrasound-based measures of resistance vessel function in skeletal muscle. Indeed, the focus is on methods used to assess resistance vessel function and not upstream conduit artery function (i.e., macrovasculature), which has been expertly reviewed elsewhere. In particular, we address topics related to experimental design, data collection, and signal processing as well as review common procedures used to assess resistance vessel function, including postocclusive reactive hyperemia, passive limb movement, acute single limb exercise, and pharmacological interventions.


Assuntos
Fármacos Cardiovasculares/farmacologia , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/diagnóstico por imagem , Ultrassonografia Doppler/normas , Resistência Vascular/fisiologia , Humanos , Músculo Esquelético/efeitos dos fármacos , Projetos de Pesquisa , Resistência Vascular/efeitos dos fármacos
10.
Nutrients ; 11(10)2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31547503

RESUMO

This study examined the effects of anthocyanin-rich antioxidant juice (AJ) on the recovery of exercise-induced muscle damage (EIMD) and the running economy (RE) following downhill running (DHR). Thirty healthy young men were randomly divided into two blinded groups and consumed either AJ or placebo (PLA) for nine days (240 mL twice-a-day). On day 5, the participants from both groups ran downhill (-15%) for 30 min at 70% of their maximal oxygen uptake (VO2max) speeds. The changes in RE (oxygen uptake (VO2) and perceived effort (PE) during 5-min runs at 80%VO2max) and EIMD (isometric peak torque (IPT), muscle soreness (SOR) and serum creatine kinase activity (CK)) were compared over time and between the groups on the 4 days following DHR. VO2 and PE increased (p < 0.05) immediately following DHR for both groups and remained elevated for PLA until 48h post-DHR while fully recovering 24 h post-DHR for AJ. SOR was greater (p < 0.05) for PLA throughout the study. CK increased for both groups and was greater (p < 0.05) for PLA at 96 h post-DHR. IPT decreased for both groups but recovered faster for AJ (72 h) compared to PLA (no full recovery). AJ accelerated recovery of RE and EIMD and should be used in specific contexts, but not chronically.


Assuntos
Antocianinas/administração & dosagem , Antioxidantes/administração & dosagem , Suplementos Nutricionais , Mialgia/terapia , Corrida/fisiologia , Biomarcadores/análise , Sucos de Frutas e Vegetais , Voluntários Saudáveis , Humanos , Masculino , Músculo Esquelético/efeitos dos fármacos , Mialgia/etiologia , Mialgia/fisiopatologia , Recuperação de Função Fisiológica/efeitos dos fármacos , Método Simples-Cego , Adulto Jovem
11.
Adv Nutr ; 10(3): 452-463, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30980076

RESUMO

ß-Alanine supplementation is one of the world's most commonly used sports supplements, and its use as a nutritional strategy in other populations is ever-increasing, due to evidence of pleiotropic ergogenic and therapeutic benefits. Despite its widespread use, there is only limited understanding of potential adverse effects. To address this, a systematic risk assessment and meta-analysis was undertaken. Four databases were searched using keywords and Medical Subject Headings. All human and animal studies that investigated an isolated, oral, ß-alanine supplementation strategy were included. Data were extracted according to 5 main outcomes, including 1) side effects reported during longitudinal trials, 2) side effects reported during acute trials, 3) effect of supplementation on circulating health-related biomarkers, 4) effect of supplementation on skeletal muscle taurine and histidine concentration, and 5) outcomes from animal trials. Quality of evidence for outcomes was ascertained using the Grading of Recommendations Assessment Development and Evaluation (GRADE) framework, and all quantitative data were meta-analyzed using multilevel models grounded in Bayesian principles. In total, 101 human and 50 animal studies were included. Paraesthesia was the only reported side effect and had an estimated OR of 8.9 [95% credible interval (CrI): 2.2, 32.6] with supplementation relative to placebo. Participants in active treatment groups experienced similar dropout rates to those receiving the placebo treatment. ß-Alanine supplementation caused a small increase in circulating alanine aminotransferase concentration (effect size, ES: 0.274, CrI: 0.04, 0.527), although mean data remained well within clinical reference ranges. Meta-analysis of human data showed no main effect of ß-alanine supplementation on skeletal muscle taurine (ES: 0.156; 95% CrI: -0.38, 0.72) or histidine (ES: -0.15; 95% CrI: -0.64, 0.33) concentration. A main effect of ß-alanine supplementation on taurine concentration was reported for murine models, but only when the daily dose was ≥3% ß-alanine in drinking water. The results of this review indicate that ß-alanine supplementation within the doses used in the available research designs, does not adversely affect those consuming it.


Assuntos
Suplementos Nutricionais , beta-Alanina/administração & dosagem , Animais , Teorema de Bayes , Biomarcadores/análise , Histidina/efeitos dos fármacos , Humanos , Camundongos , Músculo Esquelético/efeitos dos fármacos , Medição de Risco , Taurina/efeitos dos fármacos
12.
Anal Biochem ; 572: 1-8, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30822397

RESUMO

The reduction-oxidation state of NAD+/NADH is critical for cellular health with NAD+ and its metabolites playing critical roles in aging and pathologies. Given the inherent autooxidation of reduced dinucleotides (i.e. NADH/NADPH), and the well-established differential stability, the accurate measurement of NAD+ and its metabolites is technically challenging. Moreover, sample processing, normalization and measurement strategies can profoundly alter results. Here we developed a rapid and sensitive liquid chromatography mass spectrometry-based method to quantify the NAD+ metabolome with careful consideration of these intrinsic chemical instabilities. Utilizing this method we assess NAD+ metabolite stabilities and determine the presence and concentrations of NAD+ metabolites in clinically relevant human samples including cerebrospinal fluid, erythrocytes, and primate skeletal muscle.


Assuntos
Eritrócitos/metabolismo , Músculo Esquelético/metabolismo , NAD/metabolismo , Espectrometria de Massas em Tandem , Acrilamidas/farmacologia , Animais , Cromatografia Líquida de Alta Pressão , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Células HEK293 , Humanos , Metaboloma/efeitos dos fármacos , Músculo Esquelético/citologia , Músculo Esquelético/efeitos dos fármacos , NAD/análise , NAD/líquido cefalorraquidiano , Niacinamida/análogos & derivados , Niacinamida/farmacologia , Piperidinas/farmacologia , Primatas , Compostos de Piridínio
13.
Physiol Rep ; 7(2): e13982, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30653856

RESUMO

This study investigated the effects of acute and chronic beetroot juice (BRJ) supplementation on submaximal exercise oxygen uptake (VO2 ), time trial (TT) performance, and contractile properties of the plantar flexors in females. Study 1: Using a double blind, randomized, crossover design, 12 recreationally active females using hormonal contraceptives supplemented acutely (2.5 h) and chronically (8 days) with 280 mL BRJ/d (~26 mmoles nitrate [ NO3- ]) or a NO3- -free placebo (PLA). On days 1 and 8, participants cycled for 10 min at 50% and 70% VO2peak and completed a 4 kJ/kg body mass TT. Plasma [ NO3- ] and nitrite ([NO2- ]) increased significantly following BRJ supplementation versus PLA. There was no effect of BRJ supplementation on VO2 at 50% or 70% VO2peak , or TT performance. Study 2: 12 recreationally active females (n = 7 from Study 1) using hormonal contraceptives participated in a baseline visit and were supplemented acutely (2.5 h) and chronically (8 days) with 280 mL BRJ/d. Maximum voluntary strength (MVC) of the plantar flexors was assessed and a torque-frequency curve performed. BRJ had no effect on MVC, voluntary activation, peak twitch torque, time to peak torque, or half relaxation time. Following both acute (46.6 ± 4.9% of 100 Hz torque) and chronic (47.2 ± 4.4%) supplementation, 10 Hz torque was significantly greater compared to baseline (32.9 ± 2.6%). In summary, BRJ may not be an effective ergogenic aid in recreationally active females as it did not reduce submaximal exercise VO2 or improve aerobic TT performance despite increasing low frequency torque production.


Assuntos
Antioxidantes/farmacologia , Desempenho Atlético/fisiologia , Beta vulgaris/química , Exercício Físico/fisiologia , Sucos de Frutas e Vegetais , Músculo Esquelético/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Adulto , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Adulto Jovem
14.
Ann Ital Chir ; 90: 580-582, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31929173

RESUMO

INTRODUCTION: Since the 1970s, in the USA, we witnessed a progressive increase of one-day surgical procedures. This attitude soon gained ground in Europe as well. In proctology, this kind of clinical approach has always been limited by the acute sensitivity of the anal- perineal area and by difficulties in attaining a complete sphincter relaxation with local anesthesia. Posterior perineal block seems to be associated with both a good pain control and an effective sphincter relaxation. MATERIAL AND METHODS: Between January 2017 and January 2018, we enrolled in our study 33 patients suffering from hemorrhoidal disease. They were all subjected to posterior perineal block. We measured anal resting pressure and squeeze pressure before and after anesthesia. Measurements where taken 5 minutes before and 15 minutes after the administration of local. RESULTS: We registered an average decrease of 39,2% of resting pressure and of 45,4% of squeeze pressure. CONCLUSIONS: We may state that perineal posterior block, while reducing striated muscle contractile activity, also causes a relevant reduction of anal basal tone. During surgical procedures done under regional anesthesia, we experienced a good sphincter relaxation, which was comparable, if not equal, to that induced by general anesthesia. In fact, 10 to 15 minutes after performing the block you could observe the elevation of the inferior margin of the exterior sphincter and the concomitant descent of the inferior margin of the internal sphincter (coaxial dislocation). KEY WORDS: Anorectal manometry, Anesthesia, Local-regional, Perineal block.


Assuntos
Canal Anal/efeitos dos fármacos , Anestesia Local/métodos , Anestésicos Locais/farmacologia , Hemorroidas/cirurgia , Manometria/métodos , Relaxamento Muscular/efeitos dos fármacos , Bloqueio Nervoso/métodos , Adulto , Idoso , Canal Anal/inervação , Canal Anal/fisiologia , Anestésicos Locais/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Pressão , Volição
15.
Sci Rep ; 8(1): 16302, 2018 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-30389963

RESUMO

Congenital muscular dystrophy with laminin α2 chain-deficiency (LAMA2-CMD) is a severe muscle disorder with complex underlying pathogenesis. We have previously employed profiling techniques to elucidate molecular patterns and demonstrated significant metabolic impairment in skeletal muscle from LAMA2-CMD patients and mouse models. Thus, we hypothesize that skeletal muscle metabolism may be a promising pharmacological target to improve muscle function in LAMA2-CMD. Here, we have investigated whether the multifunctional medication metformin could be used to reduce disease in the dy2J/dy2J mouse model of LAMA2-CMD. First, we show gender disparity for several pathological hallmarks of LAMA2-CMD. Second, we demonstrate that metformin treatment significantly increases weight gain and energy efficiency, enhances muscle function and improves skeletal muscle histology in female dy2J/dy2J mice (and to a lesser extent in dy2J/dy2J males). Thus, our current data suggest that metformin may be a potential future supportive treatment that improves many of the pathological characteristics of LAMA2-CMD.


Assuntos
Disparidades nos Níveis de Saúde , Lamina Tipo A/deficiência , Metformina/administração & dosagem , Músculo Esquelético/efeitos dos fármacos , Distrofias Musculares/tratamento farmacológico , Distrofia Muscular Animal/tratamento farmacológico , Administração Oral , Animais , Modelos Animais de Doenças , Progressão da Doença , Feminino , Humanos , Lamina Tipo A/genética , Laminina/genética , Masculino , Camundongos , Músculo Esquelético/patologia , Distrofias Musculares/genética , Distrofias Musculares/patologia , Distrofia Muscular Animal/genética , Distrofia Muscular Animal/patologia , Fatores Sexuais , Resultado do Tratamento
16.
J Clin Endocrinol Metab ; 103(10): 3757-3766, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30113648

RESUMO

Context: Skeletal muscle endocannabinoids and sphingolipids (particularly sphingomyelins) are inversely associated with sleeping energy expenditure (SLEEP) in humans. The endocannabinoid system may increase sphingolipid synthesis via cannabinoid receptor-1. Objective: To investigate in human skeletal muscle whether endocannabinoids are responsible for the effect of sphingomyelins on SLEEP. Design: Muscle endocannabinoid [anandamide (AEA), 2-arachidonoylglycerol (2-AG)], endocannabinoid congeners [oleoylethanolamide (OEA), palmitoylethanolamide (PEA)], and sphingomyelin content were measured with liquid chromatography/mass spectrometry. SLEEP was assessed in a whole-room indirect calorimeter. Mediation analyses tested whether the inverse associations between sphingomyelins and SLEEP depended on endocannabinoids and endocannabinoid-related OEA and PEA. Setting: Inpatient study. Participants: Fifty-three Native Americans who are overweight. Main Outcome Measure: SLEEP. Results: AEA (r = 0.45, P = 0.001), 2-AG (r = 0.47, P = 0.0004), OEA (r = 0.27, P = 0.05), and PEA (r = 0.53, P < 0.0001) concentrations were associated with the total sphingomyelin content. AEA, OEA, and PEA correlated with specific sphingomyelins (SM18:1/23:0, SM18:1/23:1, and SM18:1/26:1) previously reported to be determinants of SLEEP in Native Americans (all r > 0.31, all P < 0.03). Up to half of the negative effect of these specific sphingomyelins on SLEEP was accounted for by AEA (all P < 0.04), rendering the direct effect by sphingomyelins per se on SLEEP negligible (P > 0.05). Conclusions: In skeletal muscle, AEA is responsible for the sphingomyelin effect on SLEEP, indicating that endocannabinoids and sphingomyelins may jointly reduce human whole-body energy metabolism.


Assuntos
Ácidos Araquidônicos/farmacologia , Agonistas de Receptores de Canabinoides/farmacologia , Sinergismo Farmacológico , Endocanabinoides/farmacologia , Metabolismo Energético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Alcamidas Poli-Insaturadas/farmacologia , Sono/fisiologia , Esfingomielinas/farmacologia , Adulto , Feminino , Seguimentos , Humanos , Indígenas Norte-Americanos , Masculino , Músculo Esquelético/efeitos dos fármacos , Sono/efeitos dos fármacos
17.
Mol Cell Endocrinol ; 460: 134-151, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-28736255

RESUMO

Augmenting glucose utilization and energy expenditure in skeletal muscle via AMP-activated protein kinase (AMPK) is an imperative mechanism for the management of type 2 diabetes. Chemical derivatives (2a-2h, 3, 4a-4d, 5) of the isoalantolactone (K007), a bioactive molecule from roots of Inula racemosa were synthesized to optimize the bioactivity profile to stimulate glucose utilization in skeletal muscle cells. Interestingly, 4a augmented glucose uptake, driven by enhanced translocation of glucose transporter 4 (GLUT4) to cell periphery in L6 rat skeletal muscle cells. The effect of 4a was independent to phosphatidylinositide-3-kinase (PI-3-K)/Akt pathway, but mediated through Liver kinase B1 (LKB1)/AMPK-dependent signaling, leading to activation of downstream targets acetyl coenzyme A carboxylase (ACC) and sterol regulatory element binding protein 1c (SREBP-1c). In db/db mice, 4a administration decreased blood glucose level and improved body mass index, lipid parameters and glucose tolerance associated with elevation of GLUT4 expression in skeletal muscle. Moreover, 4a increased energy expenditure via activating substrate utilization and upregulated the expression of thermogenic transcription factors and mitochondrial proteins in skeletal muscle, suggesting the regulation of energy balance. These findings suggest the potential implication of isoalantolactone derivatives for the management of diabetes.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Diabetes Mellitus Experimental/metabolismo , Metabolismo Energético/efeitos dos fármacos , Glucose/metabolismo , Músculo Esquelético/metabolismo , Sesquiterpenos/farmacologia , Transdução de Sinais , Animais , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Diabetes Mellitus Experimental/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Transportador de Glucose Tipo 4/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Masculino , Camundongos Endogâmicos C57BL , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Transporte Proteico , Ratos , Sesquiterpenos/química , Fatores de Tempo
18.
J Med Ultrason (2001) ; 45(1): 137-141, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28271231

RESUMO

PURPOSE: Our objective in this study was to assess the changes in medial gastrocnemius muscle (GCM) stiffness after botulinum toxin A (BTA) injection in children with cerebral palsy (CP) by using acoustic radiation force impulse (ARFI) elastography and to research the usability of this technique in clinical practice. MATERIALS AND METHODS: Twenty-four spastic lower extremities of 12 children with CP were assessed. BTA injection treatment was applied to the medial GCM. Muscle stiffness was measured with the ARFI technique before the procedure and a month after the procedure. The patients were assessed with the modified Ashworth scale (MAS) in the physiotherapy department at about the same time. Shear wave velocity (SWV) values and MAS scores before and after the treatment were compared. RESULTS: Mean SWV values were measured as 3.20 ± 0.14 m/s before BTA and as 2.45 ± 0.21 m/s after BTA, and the difference between them was found to be statistically significant (p < 0.001). Mean MAS score (2.33 ± 0.70) after BTA decreased significantly when compared to the score before BTA (2.96 ± 0.62) (p = 0.001). SWV values positively correlated with MAS scores (ρ = 0.578, p = 0.003). The interobserver agreement expressed as interclass correlation coefficient (ICC) was 0.65 (95% CI 0.33-0.84, p < 0.001). CONCLUSION: ARFI elastography for identifying structural changes that occur in the spastic muscle after BTA injection in children with CP can yield more valuable information with combined use of MAS.


Assuntos
Toxinas Botulínicas Tipo A/administração & dosagem , Paralisia Cerebral/complicações , Técnicas de Imagem por Elasticidade , Espasticidade Muscular/diagnóstico por imagem , Fármacos Neuromusculares/administração & dosagem , Adolescente , Criança , Estudos de Viabilidade , Feminino , Humanos , Injeções , Masculino , Espasticidade Muscular/tratamento farmacológico , Espasticidade Muscular/etiologia , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/efeitos dos fármacos
19.
Aesthet Surg J ; 37(10): 1146-1156, 2017 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-29040400

RESUMO

BACKGROUND: Hypertrophy of the gastrocnemius muscle is considered to be a hindrance to lower leg beauty in the Asian aesthetic market. A noninvasive technique that has been gaining recognition involves botulinum toxin A injection; however, there are no proper guidelines or standardized protocols for the administration of botulinum toxin to correct gastrocnemius hypertrophy. OBJECTIVES: This study sought to determine the most effective botulinum toxin injection method for correcting the contour of the lower leg calf, as well as to determine the dose that can produce the maximum effect in meeting the demands of the physician and patient. METHODS: Eighteen female patients aged between 18 and 35 years were enrolled in this study from January 2015 to July 2015. Two injection methods were compared: (I) 48 injection points with a distance of 2 cm between every point; and (II) 10 injection points. Magnetic resonance imaging examinations were conducted at baseline prior to treatment and at one month and 6 months after treatment. A 3-dimensional study was performed to analyze the volumetric changes. RESULTS: The most effective and significant treatment method for hypertrophic gastrocnemius muscle was the 48-point method (scattering injection). Following injection, this method exhibited a significant level of satisfaction with outcome. CONCLUSIONS: Our study reveals that injection dosage and method have a strong relationship with achieving a better contouring result. LEVEL OF EVIDENCE: 3.


Assuntos
Contorno Corporal/métodos , Toxinas Botulínicas Tipo A/uso terapêutico , Imageamento Tridimensional , Músculo Esquelético/efeitos dos fármacos , Fármacos Neuromusculares/uso terapêutico , Adulto , Ásia , Beleza , Contorno Corporal/psicologia , Contorno Corporal/normas , Feminino , Humanos , Hipertrofia/tratamento farmacológico , Injeções Intramusculares/métodos , Injeções Intramusculares/normas , Perna (Membro) , Imageamento por Ressonância Magnética , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/patologia , Guias de Prática Clínica como Assunto , Adulto Jovem
20.
Toxicol Pathol ; 45(4): 506-525, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28485676

RESUMO

Clofibrate is a known rodent hepatotoxicant classically associated with hepatocellular hypertrophy and increased serum activities of cellular alanine aminotransferase/aspartate aminotransferase (ALT/AST) in the absence of microscopic hepatocellular degeneration. At toxic dose, clofibrate induces liver and skeletal muscle injury. The objective of this study was to assess novel liver and skeletal muscle biomarkers following clofibrate administration in Wistar rats at different dose levels for 7 days. In addition to classical biomarkers, liver injury was assessed by cytokeratin 18 (CK18) cleaved form, high-mobility group box 1, arginase 1 (ARG1), microRNA 122 (miR-122), and glutamate dehydrogenase. Skeletal muscle injury was evaluated with fatty acid binding protein 3 (Fabp3) and myosin light chain 3 (Myl3). Clofibrate-induced hepatocellular hypertrophy and skeletal muscle degeneration (type I rich muscles) were noted microscopically. CK, Fabp3, and Myl3 elevations correlated to myofiber degeneration. Fabp3 and Myl3 outperformed CK for detection of myofiber degeneration of minimal severity. miR-122 and ARG1 results were significantly correlated and indicated the absence of liver toxicity at low doses of clofibrate, despite increased ALT/AST activities. Moreover, combining classical and novel biomarkers (Fabp3, Myl3, ARG1, and miR-122) can be considered a valuable strategy for differentiating increased transaminases due to liver toxicity from skeletal muscle toxicity.


Assuntos
Anticolesterolemiantes/efeitos adversos , Biomarcadores/sangue , Doença Hepática Induzida por Substâncias e Drogas/patologia , Clofibrato/efeitos adversos , Fígado/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Anticolesterolemiantes/administração & dosagem , Arginase/sangue , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Colesterol/sangue , Colinesterases/sangue , Clofibrato/administração & dosagem , Creatinina/sangue , Relação Dose-Resposta a Droga , Proteína 3 Ligante de Ácido Graxo/sangue , Glutamato Desidrogenase/sangue , Queratina-18/sangue , Fígado/metabolismo , Masculino , MicroRNAs/sangue , Músculo Esquelético/metabolismo , Cadeias Leves de Miosina/sangue , Ratos , Ratos Wistar , Triglicerídeos/sangue
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