Functional and Structural Brain Damage in Friedreich's Ataxia

Friedreich's ataxia (FRDA) is a rare hereditary neurodegenerative disorder caused by a GAA repeat expansion in the FXN gene. There is still no cure or quantitative biomarkers reliaby correlating with the progression rate and disease severity. Investigation of functional and structural alterations characterizing white (WM) and gray matter (GM) in FRDA are needed prerequisite to monitor progression and response to treatment. Here we report the results of a multimodal cross-sectional MRI study of FRDA including Voxel-Based Morphometry (VBM), diffusion-tensor imaging (DTI), functional MRI (fMRI), and a correlation analysis with clinical severity scores. Twenty-one early-onset FRDA patients and 18 age-matched healthy controls (HCs) were imaged at 3T. All patients underwent a complete cognitive and clinical assessment with ataxia scales. VBM analysis showed GM volume reduction in FRDA compared to HCs bilaterally in lobules V, VI, VIII (L>R), as well as in the crus of cerebellum, posterior lobe of the vermis, in the flocculi and in the left tonsil. Voxel-wise DTI analysis showed a diffuse fractional anisotropy reduction and mean, radial, axial (AD) diffusivity increase in both infratentorial and supratentorial WM. ROI-based analysis confirmed the results showing differences of the same DTI metrics in cortico-spinal-tracts, forceps major, corpus callosum, posterior thalamic radiations, cerebellar penduncles. Additionally, we observed increased AD in superior (SCP) and middle cerebellar peduncles. The WM findings correlated with age at onset (AAO), short-allelle GAA, and disease severity. The intragroup analysis of fMRI data from right-handed 14 FRDA and 15 HCs showed similar findings in both groups, including activation in M1, insula and superior cerebellar hemisphere (lobules V-VIII). Significant differences emerged only during the non-dominant hand movement, with HCs showing a stronger activation in the left superior cerebellar hemisphere compared to FRDA. Significant correlations were found between AAO and the fMRI activation in cerebellar anterior and posterior lobes, insula and temporal lobe. Our multimodal neuroimaging protocol suggests that MRI is a useful tool to document the extension of the neurological impairment in FRDA.

Integrated care of muscular dystrophies in Italy. Part 1. Pharmacological treatment and rehabilitative interventions

This paper describes the pharmacological therapies and rehabilitative interventions received by 502 patients with Muscular Dystrophies, evaluated in relation to patient's socio-demographic and clinical variables, and geographical areas. Data were collected by the MD-Socio-Demographic and Clinical Schedule (MD-SC-CS) and by the Family Problems Questionnaire (FPQ). The most part of the enrolled patients were in drug treatment. The number of the medications increased in relation to patient's age, disability degree and duration of illness and was higher among patients with Duchenne Muscular Dystrophy (DMD) compared with Becker (BMD) or Limb-Girdle Muscular Dystrophies (LGMD). Steroids (deflazacort or prednisone) were the drug most frequently used, followed by cardiologic and bone metabolism drugs. In general, patients using steroids were younger and had a shorter duration of illness; patients using cardiac drugs and dietary supplements were older and had a longer duration of illness. Rehabilitative interventions were provided to about 70% (351/502) of patients, mainly DMD. Of these, physiotherapy was the more frequent treatment (96.6%) and was prevalently performed in rehabilitative centres (about 70% of patients) and at home in only 30%. Hydrokinetic-therapy was practiced by 6.8% of patients. Respiratory rehabilitation was provided to 47.0% of patients (165/351) and assisted mechanical ventilaventilation to 13.1% (46). The amount of rehabilitative interventions increased in relation to the patient's age, level of disability and duration of illness. Compared to Central and Northern Italy, in Southern Italy there was a higher attention to cardiological impairment as shown by a higher number of patients receiving heart drugs. No statistically significant differences concerning the possibility to have access to rehabilitative interventions were noted among the three geographical areas. However, patient living in Southern Italy tend to receive rehabilitation more often at home.

Clinical and Paraclinical Indicators of Motor System Impairment in Hereditary Spastic Paraplegia: A Pilot Study

BACKGROUND

Hereditary spastic paraplegias (HSP) are a composite and genetically heterogeneous group of conditions mainly expressed by the impairment of the central motor system ("pure" forms). The involvement of other components of the central nervous system or of other systems is described in the "complicate" forms. The definition of an investigation protocol capable, by assembling clinical and paraclinical indicators to fully represent the extent of the motor system impairment, would help both the clinical handling of these conditions and contribute to our understanding of their pathogenesis.

METHODS

We applied a clinical and paraclinical protocol which included tools exploring motor and non motor functioning, neurophysiology and MRI to a composite cohort of 70 molecularly defined HSP patients aged 3 to 65, to define for each indicator its significance in detailing the presence and the severity of the pathology.

RESULTS

Clinically increased deep tendon reflexes and lower limb (LL) weakness are constant findings in all patients. The "complicated" forms are characterized by peripheral motor impairment, cognitive and cerebellar involvement. The Spastic Paraplegia Rating Scale efficiently reflects the severity of functional problems and correlates with disease duration. Neurophysiology consistently documents the impairment of the central motor pathway to the LLs. Nevertheless, the upper extremities and sensory system involvement is a frequent finding. MRI diffusion tensor imaging (DTI) highlighted a significant alteration of FA and MD. Combining the sampling of the various portion of the cortico-spinal tract (CST) DTI consistently discriminated patients from controls.

CONCLUSION

We propose a graded clinical and paraclinical protocol for HSP phenotype definition, indicating for each tool the discriminative and descriptive capacity. Our protocol applied to 9 different forms of HSP showed that the functional impairment often extends beyond the CST. The novel DTI approach may add significant elements in disease recognition, staging and mapping.

Burden, professional support, and social network in families of children and young adults with muscular dystrophies

Introduction: This study explores burden and social and professional support in families of young patients with muscular dystrophies (MDs) in Italy. Methods: The study was carried out on 502 key relatives of 4‐ to 25‐year‐old patients suffering from Duchenne, Becker, or Limb‐Girdle MD who were living with at least 1 adult relative. Results: A total of 77.1% of relatives reported feelings of loss, 74.0% had feelings of sadness, and 59.1% had constraints in leisure activities. Burden was higher among relatives of patients with higher disability and who spent more daily hours in caregiving. Practical difficulties were higher among relatives who perceived lower help in patient emergencies and less practical support by their social network. Psychological burden was higher in those relatives who were unemployed, those with poorer support in emergencies, and those with lower social contacts. Conclusions: Caring for patients with MDs may be demanding for relatives even in the early stages of these disorders, especially when social support is poor and the patient's disability increases. Muscle Nerve52: 13–21, 2015

"I have got something positive out of this situation": psychological benefits of caregiving in relatives of young people with muscular dystrophy

This paper focuses on the psychological benefits of caregiving in key relatives of patients with muscular dystrophies (MD), a group of rare diseases characterized by progressive weakness and restriction of the patient's functional abilities. We describe whether relatives perceived caregiving to be a positive experience and test whether relatives' perceptions vary in relation to their view of the patient as a valued person, the degree of involvement in care, and the level of support provided by social network and professionals. The study sample included 502 key relatives of patients aged 4-25 years, suffering from Duchenne, Becker, or limb-girdle MD, in treatment for at least 6 months to one of the eight participating centers, living with at least one relative aged 18-80 years. Of key relatives, 88 % stated that they had gotten something positive out of the situation, 96 % considered their patients to be sensitive, and 94 % viewed their patients as talented. Positive aspects of caregiving were more recognized by key relatives who were more convinced that the patient was sensitive and who perceived that they received higher level of professional help and psychological social support. These results suggest that most key relatives consider that their caregiving experience has had a positive impact on their lives, despite the practical difficulties of caring for patients with MD. Professionals should help relatives to identify the benefits of caregiving without denying its difficulties. Clinicians themselves should develop positive attitudes towards family involvement in the care of patients with long-term diseases.

Defective autophagy in spastizin mutated patients with hereditary spastic paraparesis type 15

Hereditary spastic paraparesis type 15 is a recessive complicated form of the disease clinically characterized by slowly progressive spastic paraparesis and mental deterioration with onset between the first and second decade of life. Thinning of corpus callosum is the neuroradiological distinctive sign frequently associated with white matter abnormalities. The causative gene, ZFYVE26, encodes a large protein of 2539 amino acid residues, termed spastizin, containing three recognizable domains: a zinc finger, a leucine zipper and a FYVE domain. Spastizin protein has a diffuse cytoplasmic distribution and co-localizes partially with early endosomes, the endoplasmic reticulum, microtubules and vesicles involved in protein trafficking. In addition, spastizin localizes to the mid-body during the final step of mitosis and contributes to successful cytokinesis. Spastizin interacts with Beclin 1, a protein required for cytokinesis and autophagy, which is the major lysosome-mediated degradation process in the cell. In view of the Beclin 1-spastizin interaction, we investigated the possible role of spastizin in autophagy. We carried out this analysis by using lymphoblast and fibroblast cells derived from four different spastizin mutated patients (p.I508N, p.L243P, p.R1209fsX, p.S1312X) and from control subjects. Of note, the truncating p.R1209fsX and p.S1312X mutations lead to loss of spastizin protein. The results obtained indicate that spastizin interacts with the autophagy related Beclin 1-UVRAG-Rubicon multiprotein complex and is required for autophagosome maturation. In cells lacking spastizin or with mutated forms of the protein, spastizin interaction with Beclin 1 is lost although the formation of the Beclin 1-UVRAG-Rubicon complex can still be observed. However, in these cells we demonstrate an impairment of autophagosome maturation and an accumulation of immature autophagosomes. Autophagy defects with autophagosome accumulation can be observed also in neuronal cells upon spastizin silencing. These results indicate that autophagy is a central process in the pathogenesis of complicated forms of hereditary spastic paraparesis with thin corpus callosum.

Frequency and characterisation of anoctamin 5 mutations in a cohort of Italian limb-girdle muscular dystrophy patients

Limb-girdle muscular dystrophy (LGMD) 2L, caused by mutations in the anoctamin 5 (ANO5) gene, is the third most common LGMD in Northern and Central Europe, where the c.191dupA mutation causes the majority of cases. We evaluated data from 228 Italian LGMD patients to determine the prevalence of LGMD2L and the c.191dupA mutation, and to describe the clinical, muscle biopsy, and magnetic resonance imaging findings in these patients. Forty-three patients who lacked molecular diagnosis were studied for ANO5 mutations, and four novel mutations were found in three probands. Only one proband carried the c.191dupA mutation, which was compound heterozygous with c.2516T>G. Two probands were homozygous for the c.1627dupA and c.397A>T mutations, respectively, while a fourth proband had a compound heterozygous status (c.220C>T and c.1609T>C). Therefore occurrence and molecular epidemiology of LGMD2L in this Italian cohort differed from those observed in other European countries. ANO5 mutations accounted for ∼2% of our sample. Affected patients exhibited benign progression with variable onset and an absence of cardiac and respiratory impairment; muscle biopsy generally showed mild signs, except when performed on the quadriceps muscles; MRI showed predominant involvement of the posterior thigh. Overall these common clinical, morphological and imaging findings could be useful in differential diagnosis.

Nitric oxide donor and non steroidal anti inflammatory drugs as a therapy for muscular dystrophies: evidence from a safety study with pilot efficacy measures in adult dystrophic patients

This open-label, single centre pilot study was designed to evaluate safety and tolerability of the combination of the drugs isosorbide dinitrate, a nitric oxide donor, and ibuprofen, a non steroid anti-inflammatory drug, in a cohort of adult dystrophic patients (Duchenne, Becker and Limb-Girdle Muscular Dystrophy). Seventy-one patients were recruited: 35, treated with the drug combination for 12 months, and 36 untreated. Safety and adverse events were assessed by reported signs and symptoms, physical examinations, blood tests, cardiac and respiratory function tests. Exploratory outcomes measure, such as the motor function measure scale, were also applied. Good safety and tolerability profiles of the long-term co-administration of the drugs were demonstrated. Few and transient side effects (i.e. headache and low blood pressure) were reported. Additionally, exploratory outcomes measures were feasible in all the disease population studied and evidenced a trend towards amelioration that reached statistical significance in one dimension of the MFM scale. Systemic administration of ibuprofen and isosorbide dinitrate provides an adequate safety margin for clinical studies aimed at assessing efficacy.

Low abdominal contribution to breathing as daytime predictor of nocturnal desaturation in adolescents and young adults with Duchenne Muscular Dystrophy

In the respiratory management of DMD patients it is still under debate what parameter should indicate the correct timing for institution of nocturnal non-invasive ventilation (NIV), in addition to forced vital capacity, which is generally considered as a prognostic marker of disease progression. The aim of this study was to determine if volume variations of rib cage and abdominal compartments measured by Opto-Electronic Plethysmography can be helpful to distinguish between those patients who are in the early stages of nocturnal oxygen desaturation development and those who do not yet. Pulmonary function, abdominal contribution to tidal volume and to inspiratory capacity (%Abd IC) and a set of breathing pattern indexes were assessed in 40 DMD patients older than 14 years and not yet under nocturnal NIV. ROC analysis revealed that among all the considered parameters, %Abd IC in supine position was the best discriminator between DeSat (at least 10% of the night time with SpO(2) < 95%) and NonDeSat patients, providing an area under the curve with 95%CI equal to 0.752. In conclusion, in adolescents and adults DMD patients who present either no sign or only mild nocturnal oxygen desaturation, a reduced abdominal contribution to inspiratory capacity is a marker of the onset of diaphragm weakness and should be considered to identify the correct timing for the institution of nocturnal NIV.

Lactate detection in the brain of growth-restricted fetuses with magnetic resonance spectroscopy

OBJECTIVE

The objective of the study was to determine the feasibility of detecting fetal brain lactate, a marker of fetal metabolic acidemia, using a noninvasive technique, proton magnetic resonance spectroscopy ((1)H MRS), in intrauterine growth-restricted (IUGR) fetuses.

STUDY DESIGN

In vivo human fetal brain lactate detection was determined by (1)H MRS in 5 fetuses with IUGR. Oxygenation and acid-base balance data were obtained at birth.

RESULTS

(1)H MRS analysis showed the presence of a lactate peak in the brain of the most severely affected IUGR fetus, with abnormal umbilical artery Doppler and fetal heart rate tracing. This finding was consistent with the low oxygen content and high lactic acid concentration observed in umbilical blood obtained at delivery.

CONCLUSION

(1)H MRS allows the noninvasive detection of cerebral lactate in IUGR fetuses. Lactate detected by (1)H MRS may represent a possible marker of in utero cerebral injury or underperfusion.

Human fetal brain chemistry as detected by proton magnetic resonance spectroscopy

Magnetic resonance spectroscopy represents an invaluable tool for the in vivo study of brain development at the chemistry level. Whereas magnetic resonance spectroscopy has received wide attention in pediatric and adult settings, only a few studies were performed on the human fetal brain. They revealed changes occurring throughout gestation in the levels of the main metabolites detected by proton magnetic resonance spectroscopy (N-acetylaspartate, choline, myo-inositol, creatine, and glutamate), providing a reference for the normal metabolic brain development. Throughout the third trimester of gestation, N-acetylaspartate gradually increases, whereas choline undergoes a slow reduction during the process of myelination. Less clear are the modifications in creatine, myo-inositol, and glutamate levels. Under conditions of fetal distress, the meaning of lactate detection is unclear, and further studies are needed. Another field for investigation involves the possibility of early detection of glutamate levels in fetuses at risk for hypoxic-ischemic encephalopathy, because the role of glutamate excitotoxicity in this context is well-established. Because metabolic modifications may precede functional or morphologic changes in the central nervous system, magnetic resonance spectroscopy may likely serve as a powerful, noninvasive tool for the early diagnosis and prognosis of different pathologic conditions.