Kira Philipsen Prahm

Effect of sildenafil on skeletal and cardiac muscle in Becker muscular dystrophy.

Patients with Becker muscular dystrophy (BMD) and Duchenne muscular dystrophy lack neuronal nitric oxide synthase (nNOS). nNOS mediates physiological sympatholysis, thus ensuring adequate blood supply to working muscle. In mice lacking dystrophin, restoration of nNOS effects by a phosphodiesterase 5 (PDE5) inhibitor (sildenafil) improves skeletal and cardiac muscle performance. Sildenafil also improves blood flow in patients with BMD. We therefore hypothesized that sildenafil would improve blood flow, maximal work capacity, and heart function in patients with BMD.

Anti-gravity training improves walking capacity and postural balance in patients with muscular dystrophy.

Recent studies in patients with muscular dystrophies suggest positive effects of aerobic and strength training. These studies focused training on using bicycle ergometers and conventional strength training, which precludes more severely affected patients from participating, because of their weakness. We investigated the functional effects of combined aerobic and strength training in patients with Becker and limb-girdle muscular dystrophies with knee muscle strength levels as low as 3% of normal strength. Eight patients performed 10 weeks of aerobic and strength training on an anti-gravity treadmill, which offered weight support up to 80% of their body weight. Six minute walking distance, dynamic postural balance, and plasma creatine kinase were assessed 10 weeks prior to training, immediately before training and after 10 weeks of training. Training elicited an improvement of walking distance by 8±2% and dynamic postural balance by 13±4%, indicating an improved physical function. Plasma creatine kinase remained unchanged. These results provide evidence that a combination of aerobic and strength training during anti-gravity has the potential to safely improve functional ability in severely affected patients with Becker and limb-girdle muscular dystrophies.

Aerobic training and postexercise protein in facioscapulohumeral muscular dystrophy RCT study

Objective: To investigate the effect of regular aerobic training and postexercise protein-carbohydrate supplementation in patients with facioscapulohumeral muscular dystrophy (FSHD). Methods: In this randomized, double-blind, placebo-controlled parallel study, we randomized untrained men (n = 21) and women (n = 20) with FSHD (age 19–65 years) to 2 training groups—training with protein supplement (n = 18) and training with placebo supplement (n = 13)—and a nonintervention control group (n = 10). We assessed fitness, walking speed, muscle strength, questionnaires, and daily activity levels before and after 12 weeks of interventions. Training involved 36 sessions of 30-minute cycle-ergometer training. After each session, patients drank either a protein-carbohydrate or placebo beverage. Results: In the trained participants, fitness, workload, and walking speed improved (10% [confidence interval (CI) 4%–15%], 18% [CI 10%–26%], 7% [CI 4%–11%], respectively, p < 0.001, number needed to treat = 2.1). Self-assessed physical capacity and health (Short Form–36) also improved. Muscle strength and daily activity levels did not change with training. Protein-carbohydrate supplementation did not result in further improvements in any tests compared to training alone. Conclusions: This randomized, controlled study showed that regular endurance training improves fitness, walking speed, and self-assessed health in patients with FSHD without causing muscle damage. Postexercise protein-carbohydrate supplementation does not add any further improvement to training effects alone. Classification of evidence: This study provides Class II evidence that regular aerobic training with or without postexercise protein-carbohydrate supplementation improves fitness and workload in patients with FSHD.

Skeletal muscle metabolism is impaired during exercise in glycogen storage disease type III

Objective: Glycogen storage disease type IIIa (GSDIIIa) is classically regarded as a glycogenosis with fixed weakness, but we hypothesized that exercise intolerance in GSDIIIa is related to muscle energy failure and that oral fructose ingestion could improve exercise tolerance in this metabolic myopathy. Methods: We challenged metabolism with cycle-ergometer exercise and measured substrate turnover and oxidation rates using stable isotope methodology and indirect calorimetry in 3 patients and 6 age-matched controls on 1 day, and examined the effect of fructose ingestion on exercise tolerance in the patients on another day. Results: Total fatty acid oxidation rates during exercise were higher in patients than controls, 32.1 (SE 1.2) vs 20.7 (SE 0.5; range 15.8–29.3) μmol/kg/min (p = 0.048), and oxidation of carbohydrates was lower in patients, 1.0 (SE 5.4) vs 38.4 (SE 8.0; range 23.0–77.1) μmol/kg/min (p = 0.024). Fructose ingestion improved exercise tolerance in the patients. Conclusion: Similar to patients with McArdle disease, in whom muscle glycogenolysis is also impaired, GSDIIIa is associated with a reduced skeletal muscle oxidation of carbohydrates and a compensatory increase in fatty acid oxidation, and fructose ingestion improves exercise tolerance. Our results indicate that GSDIIIa should not only be viewed as a glycogenosis with fixed skeletal muscle weakness, but should also be considered among the glycogenoses presenting with exercise-related dynamic symptoms caused by muscular energy deficiency. Classification of evidence: This study provides Class IV evidence that ingestion of fructose improves exercise tolerance in patients with GSDIIIa.

The prognostic value of dividing epithelial ovarian cancer into type I and type II tumors based on pathologic characteristics

OBJECTIVE To investigate the prognostic significance of dividing epithelial ovarian cancer (EOC) in type I and type II tumors based on pathologic variables. METHODS We used the Danish Gynecologic Cancer Database to identify all patients diagnosed with EOC from 2005 to 2012. Information on histologic type and grade were used to classify tumors as either type I or type II. Death, and several prognostic factors were used in the multivariate Cox regression, and Landmark analysis was used to estimate hazard ratios of all-cause mortality. RESULTS Among 2660 patients diagnosed with EOC, 735 were categorized as type I tumors, and 1925 as type II tumors. Patients with type II EOC were more frequently diagnosed in late FIGO stages (stages III-IV) than patients with type I EOC (78.1% vs. 32.1% respectively; P<0.001). Time dependent multivariate Cox analysis, adjusted for known prognostic variables, showed no significant difference in survival within the first two years after diagnosis, however, after 730days of follow-up a significantly increased overall survival for type I tumors was observed (hazard ratio 1.72, 95% confidence interval: 1.28-2.31, P<0.001). Similarly the Landmark analysis for survival confirmed the increased overall survival for type I tumors after two years of follow-up (hazard ratio: 1.85, 95% confidence interval: 1.35-2.54, P<0.001). CONCLUSION Classification of EOC in type I and type II tumors based on pathologic variables was associated with an increased risk of death for type II tumors after two years of follow-up, while no increased risk was seen during the first two years of follow-up.

Current status on microRNAs as biomarkers for ovarian cancer

Ovarian cancer (OC) is the most lethal gynecological malignancy in the Western world, and has a very poor prognosis, often due to late diagnosis and emergence of chemotherapy resistance. Therefore, there is an essential need for new diagnostic and prognostic markers that can improve and initiate more personalized treatment, eventually improving survival of the patients. MicroRNAs are small, non‐coding RNA molecules, that post‐transcriptionally regulate gene expression. Several studies have within the last decade shown that microRNAs are deregulated in OC and have potential as diagnostic and prognostic biomarkers for OC. Recently studies have also focused on microRNAs as predictors of chemotherapy responses and their potential as therapeutic targets. However, many of the published studies are difficult to interpret as a whole due to various methods of analysis. Future focus should be aimed at developing a general standardized analytical method, which can limit differences between studies thus allowing easier comparison across them. In addition, validation of studies in independent series that ideally should be histotype‐specific is essential to determine the clinical role of microRNAs in different types of OC. In this review we summarize the current knowledge of microRNAs as potential biomarkers for OC, with focus on their clinical relevance.

Decreased Variability of the 6-Minute Walk Test by Heart Rate Correction in Patients with Neuromuscular Disease

Objective The 6-minute walk test is widely used to assess functional status in neurological disorders. However, the test is subject to great inter-test variability due to fluctuating motivation, fatigue and learning effects. We investigated whether inter-test variability of the 6MWT can be reduced by heart rate correction. Methods Sixteen patients with neuromuscular diseases, including Facioscapulohumeral muscular dystrophy, Limb-girdle muscular dystrophy, Charcot-Marie-Tooths, Dystrophia Myotonica and Congenital Myopathy and 12 healthy subjects were studied. Patients were excluded if they had cardiac arrhythmias, if they received drug treatment for hypertension or any other medical conditions that could interfere with the interpretation of the heart rate and walking capability. All completed three 6-minute walk tests on three different test-days. Heart rate was measured continuously. Results Successive standard 6-minute walk tests showed considerable learning effects between Tests 1 and 2 (4.9%; P = 0.026), and Tests 2 and 3 (4.5%; P = 0.020) in patients. The same was seen in controls between Tests 1 and 2 (8.1%; P = 0.039)). Heart rate correction abolished this learning effect. Conclusion A modified 6-minute walk test, by correcting walking distance with average heart rate during walking, decreases the variability among repeated 6-minute walk tests, and should be considered as an alternative outcome measure to the standard 6-minute walk test in future clinical follow-up and treatment trials.

Aerobic training in patients with anoctamin 5 myopathy and hyperckemia

Introduction: Anoctamin 5 deficiency has recently been defined to cause limb‐girdle muscular dystrophy type 2L (LGMD2L) with pronounced hyperCKemia. No treatment interventions have been made so far in this condition. Methods: In 6 patients with LGMD2L, we studied the effect of home‐based, pulse‐watch monitored, moderate‐intensity exercise on a cycle ergometer for 30 minutes, 3 times weekly, for 10 weeks. Plasma creatine kinase (CK) was assessed before, during, and after the program as a marker of muscle damage. Primary outcome measures were maximum oxygen uptake (VO2max) and time in the 5‐repetitions‐sit‐to‐stand test (FRSTST). Results: Training resulted in improvements in VO2max (27 ± 7%; P = 0.0001) and FRSTST time (35 ± 12%; P = 0.007). Improvements in physiologic and functional muscle testing were accompanied by stable CK levels and no reports of adverse effects. Conclusions: These findings suggest that supervised aerobic exercise training is safe and effective in improving oxidative capacity and muscle function in patients with anoctamin 5 deficiency. Muscle Nerve 50: 119–123, 2014

Clinical validation of chemotherapy predictors developed on global microRNA expression in the NCI60 cell line panel tested in ovarian cancer

Objective Ovarian cancer is the leading cause of death among gynecologic malignancies. This is partly due to a non-durable response to chemotherapy. Prediction of resistance to chemotherapy could be a key role in more personalized treatment. In the current study we aimed to examine if microRNA based predictors could predict resistance to chemotherapy in ovarian cancer, and to investigate if the predictors could be prognostic factors for progression free and overall survival. Methods Predictors of chemotherapy-resistance were developed based on correlation between miRNA expression and differences in measured growth inhibition in a variety of human cancer cell lines in the presence of Carboplatin, Paclitaxel and Docetaxel. These predictors were then, retrospectively, blindly validated in a cohort of 170 epithelial ovarian cancer patients treated with Carboplatin and Paclitaxel or Docetaxel as first line treatment. Results In a multivariate cox proportional analysis the predictors of chemotherapy-resistance were not able to predict time to progression after end of chemotherapy (hazard ratio: 0.64, 95% CI: 0.36–1.12, P = 0.117). However, in a multivariate logistic analysis, where time to progression was considered as either more or less than 6 months, the predictors match clinical observed chemotherapy-resistance (odds ratio: 0.19, 95% CI: 0.05–0.73, P = 0.015). Neither univariate nor multivariate, time-dependent, cox analysis for progression free survival (PFS) or overall survival (OS) in all 170 patients showed to match predicted resistance to chemotherapy (PFS: hazard ratio: 0.69, 95% CI: 0.40–1.19, P = 0.183, OS: hazard ratio: 0.76, 95% CI: 0.42–1.40, P = 0.386). Conclusion In the current study, microRNA based predictors of chemotherapy-resistance did not demonstrate any convincing correlation to clinical observed chemotherapy-resistance, progression free survival, or overall survival, in patients with epithelial ovarian cancer. However the predictors did reflect relapse more or less than 6 months.

Human growth hormone stabilizes walking and improves strength in a patient with dominantly inherited calpainopathy

The aim was to investigate if daily low-dose treatment with recombinant human growth hormone (somatropine) can stabilize or improve muscle strength and walking capability in a patient with dominantly inherited calpainopathy. The patient was treated with daily injections of somatropine, except for a 6-month pause, over a period of 4.5 years. Efficacy was assessed by repeated muscle dynamometry tests and 6-minute walk tests (6MWT). Strength improved in most muscle groups on treatment, deteriorated in the 6-month off treatment, and improved again when treatment was resumed. The 6MWT stabilized during the initial 18-month treatment period, then deteriorated in the 6 months off treatment and improved to pre-trial levels when treatment was resumed. The findings suggest that supplementation with somatropine, within physiological ranges, may improve muscle strength and stabilize walking capability in a patient with calpainopathy. This finding calls for testing of somatropine supplementation in muscular dystrophies in a randomized study.