Perivascular and endomysial macrophages expressing VEGF and CXCL12 promote angiogenesis in anti-HMGCR immune-mediated necrotizing myopathy.

OBJECTIVES: To study the phenotype of macrophage infiltrates and their role in angiogenesis in different idiopathic inflammatory myopathies (IIMs). METHODS: The density and distribution of the subpopulations of macrophages subsets (M1, inducible nitric oxide+, CD11c+; M2, arginase-1+), endomysial capillaries (CD31+, FLK1+), degenerating (C5b-9+) and regenerating (NCAM+) myofibres were investigated by immunohistochemistry in human muscle samples of diagnostic biopsies from a large cohort of untreated patients (n: 81) suffering from anti-3-hydroxy-3-methylglutaryl coenzyme A reductase (anti-HMGCR)+ immune mediated necrotizing myopathy (IMNM), anti-signal recognition particle (anti-SRP)+ IMNM, seronegative IMNM, DM, PM, PM with mitochondrial pathology, sporadic IBM, scleromyositis, and anti-synthetase syndrome. The samples were compared with mitochondrial myopathy and control muscle samples. RESULTS: Compared with the other IIMs and controls, endomysial capillary density (CD) was higher in anti-HMGCR+ IMNM, where M1 and M2 macrophages, detected by confocal microscopy, infiltrated perivascular endomysium and expressed angiogenic molecules such as VEGF-A and CXCL12. These angiogenic macrophages were preferentially associated with CD31+ FLK1+ microvessels in anti-HMGCR+ IMNM. The VEGF-A+ M2 macrophage density was significantly correlated with CD (rS: 0.98; P: 0.0004). Western blot analyses revealed increased expression levels of VEGF-A, FLK1, HIF-1α and CXCL12 in anti-HMGCR+ IMNM. CD and expression levels of these angiogenic molecules were not increased in anti-SRP+ and seronegative IMNM, offering additional, useful information for differential diagnosis among these IIM subtypes. CONCLUSION: Our findings suggest that in IIMs, infiltrating macrophages and microvascular cells interactions play a pivotal role in coordinating myogenesis and angiogenesis. This reciprocal crosstalk seems to distinguish anti-HMGCR associated IMNM.

Autophagy markers LC3 and p62 accumulate in immune-mediated necrotizing myopathy.

INTRODUCTION: The molecular mechanism of immune-mediated necrotizing myopathy (IMNM) remains unknown. Autophagy impairment, described in autoimmune diseases, is a key process in myofiber protein degradation flux and muscle integrity and has not been studied in IMNM. METHODS: Muscle biopsies from patients with IMNM (n = 40), dermatomyositis (DM; 24), polymyositis (PM; 8), polymyositis with mitochondrial pathology (4), sporadic inclusion body myositis (8), and controls (6) were compared by immunohistochemistry. RESULTS: The proportions of myofibers containing autophagy markers LC3b and p62 were higher in IMNM than in DM or PM and correlated with creatine kinase levels. In IMNM, compartmentalized LC3b puncta were located in regenerating and degenerating myofibers surrounded by major histocompatibility complex type II+ inflammatory cells. Several IMNM myofibers accumulated ubiquitin and misfolded protein. DISCUSSION: The detection of LC3b+ or p62+ myofibers could be used in differentiating IMNM from PM. The identification of autophagy-modifying molecules potentially could improve patients' outcomes. Muscle Nerve, 2019.

Mitochondrial genome aberrations in skeletal muscle of patients with motor neuron disease.

Our objective was to assess the role of defects of mitochondrial function as contributing factors in the pathogenesis and/or progression of amyotrophic lateral sclerosis (ALS); mitochondrial genome structural alterations were investigated. DNA lesions, point alterations and gross rearrangements were screened by specific applications of real-time PCR including an optimized rapid gene-specific method for the accurate quantification of mitochondrial DNA (mtDNA) lesions as well as sequencing on skeletal muscle biopsies of three patients presenting with motor neuron disease. We found a higher frequency of mtDNA lesions, including multiple deletions, particularly in the only SOD1 mutated patient as well as in a patient negative for mutations in SOD1 but presenting a severe form of the disease. The occurrence and the extent of mtDNA lesions of the cases here presented were consistent in all the examined clinical phenotypes of ALS (SOD1 related ALS, bulbar onset, spinal onset) and correlated with the severity of clinical course of the illness and with the presence of SOD1 mutation as well. In conclusion, the strong association with mtDNA damages supports the hypothesis that mitochondrial dysfunction in skeletal muscle may contribute to the pathogenesis and progression of ALS.

Clinical features and new molecular findings in muscle phosphofructokinase deficiency (GSD type VII).

Muscle phosphofructokinase (PFKM) deficiency, a rare disorder of glycogen metabolism also known as glycogen storage disease type VII (GSDVII), is characterized by exercise intolerance, myalgias, cramps and episodic myoglobinuria associated with compensated hemolytic anaemia and hyperuricemia. We studied five patients with PFKM deficiency coming from different Italian regions. All probands showed exercise intolerance, hyperCKemia, cramps and myoglobinuria. One patient had a mild hypertrophic cardiomyopathy. Biochemical studies revealed residual PFK activity ranging from 1 to 5%. Molecular genetic analysis identified four novel mutations in the PFKM gene. In our series of patients, clinical and laboratory features were similar in all but one patient, who had an unusual phenotype characterized by 25 ears disease history, high CK levels, hypertrophic cardiomyopathy with paroxysmal atrial fibrillation without fixed muscle weakness.

Autoimmune autonomic ganglionopathy: a possible postganglionic neuropathy.

OBJECTIVE: To evaluate postganglionic autonomic and somatic nerve fiber involvement in a patient with chronic autoimmune autonomic ganglionopathy. DESIGN: Case report. SETTING: Department of Neurological Sciences, University Federico II of Naples. PATIENT: A patient with a 16-year history of severe autonomic failure and a high nicotinic acetylcholine receptor antibody titer underwent an extensive laboratory evaluation. MAIN OUTCOME MEASURES: Evaluation of sympathetic and parasympathetic functions and sural nerve and skin biopsies. RESULTS: Clinical and laboratory evaluations showed the involvement of cardiovascular, pupillary, sudomotor, gastrointestinal, and bladder functions. Sudomotor function study and skin biopsy findings revealed postganglionic autonomic damage. Moreover, sural nerve and skin biopsy specimens provided clear evidence of somatic nerve fiber involvement. CONCLUSIONS: We demonstrated postganglionic autonomic damage that could be related to a prolonged and severe impaired synaptic transmission and we report, for the first time to our knowledge, a somatic nerve fiber involvement in autoimmune autonomic ganglionopathy.

A new locus on 3p23-p25 for an autosomal-dominant limb-girdle muscular dystrophy, LGMD1H.

Limb-girdle muscular dystrophies (LGMDs) are a genetically heterogeneous group of neuromuscular disorders with a selective or predominant involvement of shoulder and pelvic girdles. We clinically examined 19 members in a four-generation Italian family with autosomal-dominant LGMD. A total of 11 subjects were affected. Clinical findings showed variable expressivity in terms of age at onset and disease severity. Five subjects presented with a slowly progressive proximal muscle weakness, in both upper and lower limbs, with onset during the fourth-fifth decade of life, which fulfilled the consensus diagnostic criteria for LGMD. Earlier onset of the disease was observed in a group of patients presenting with muscle weakness and/or calf hypertrophy, and/or occasionally high CK and lactate serum levels. Two muscle biopsies showed morphological findings compatible with MD associated with subsarcolemmal accumulation of mitochondria and the presence of multiple mitochondrial DNA deletions. A genome-wide scan performed using microsatellite markers mapped the disease on chromosome 3p23-p25.1 locus in a 25-cM region between markers D3S1263 and D3S3685. The highest two-point LOD score was 3.26 (theta=0) at marker D3S1286 and D3S3613, whereas non-parametric analysis reached a P-value=0.0004. Four candidate genes within the refined region were analysed but did not reveal any mutations. Our findings further expand the clinical and genetic heterogeneity of LGMDs.

Molecular analysis in a family presenting with a mild form of late-onset autosomal dominant chronic progressive external ophthalmoplegia.

Nuclear genes affecting mitochondrial genome stability were screened in an Italian family presenting with autosomal dominant progressive external ophthalmoplegia (adPEO) associated with multiple mitochondrial DNA (mtDNA) deletions. We report on a heterozygous c.907C>T (p.R303W) mutation found in the N-terminal domain of the human mitochondrial DNA helicase, Twinkle protein, in six members of a family, in which two individuals manifested late-onset PEO and morphological and molecular signs of mitochondrial dysfunction along with two carriers who are presently free of disease manifestation. We also investigated if the p.R303W mutation in PEO1 gene affected the relative copy number of mitochondrial DNA genomes.

Motoneuron disease after electric injury: a case report.

Several cases of motor neuron disease (MND) after electric injury have been reported in the last number of years, but the relationship between electric injury and MND remains controversial. Herein we report the case of a 60-year-old man who developed a MND following an electrical trauma. In the case presented here, the onset of disease at the site of lightning strike and the short interval of time between the electrical injury and the clinical onset of MND raise the possibility of considering electrical shock as a trigger factor for MND.

Predictors of long survival in amyotrophic lateral sclerosis: a population-based study.

BACKGROUND: Although amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative disorder, some ALS cases can survive beyond 10 years. However, the predictors of long survival in ALS patients remain uncertain. OBJECTIVE: To define clinical predictors of long survival in a cohort of ALS incident cases. METHODS: One hundred-thirty incidents cases, diagnosed in 1998--1999 and classified according to the El Escorial criteria (EEC), were enrolled from a prospective population-based registry established in Puglia, Italy. All but two cases were followed-up until death or November 30, 2006. RESULTS: Thirteen patients (high 10% of the survivors) were classified as long survivors (LS), 13 as short survivors (SS) (low 10%), and 102 as average survivors (AS). LS presented a lower frequency of bulbar onset (8% versus 29% of AS and 39% of SS; p=0.1) and a significantly longer time between symptom onset to diagnosis [(ODI): 13 months versus 10 and 6; p=0.0005]. In multivariate analysis, predictors of long survival were younger age at diagnosis (>65 compared to < or =45 years: odds ratio (OR):18.9; 95%CI: 1.8-194.7; p=0.04), longer interval onset-diagnosis (< or =9 months compared to >9 months, OR: 7.9; 95%CI: 1.3-47; p=0.02) and clinical features with predominant upper motor neuron signs (OR: 8.5; 95%CI: 1.1-64.2; p=0.04). CONCLUSIONS: In this population-based study, younger age, longer interval onset to diagnosis, and clinical features with predominance of upper motor signs predicted long survival, while EEC category at diagnosis did not.

ALS multidisciplinary clinic and survival. Results from a population-based study in Southern Italy.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease affecting motorneurons, for which there is no effective cure. Because of the multifactorial nature of impairment and disablity in ALS, multidisciplinary clinics (MDC) have been recently introduced in the management of ALS patients; their effects on survival remain, however, largely debated. OBJECTIVE: To compare survival of ALS patients who received their care at MDC with that of patients followed by general neurology clinics. METHODS: Source of the study was a prospective population-based registry of ALS established in Puglia, Southern Italy, in 1997. We examined survival of 126 out of 130 incident ALS cases that were diagnosed during the period 1998-99. RESULTS: 84 patients (67%) were enrolled and followed by MDC and the remaining 42 (33%) by general neurological clinics. No difference in median survival time from the diagnosis was observed between patients followed by ALS multidisciplinary (17.6 months) and general clinics (18 months). No beneficial effect was present among bulbar onset ALS (11.7 versus 23 months). In multivariate analysis management by ALS MDC was associated with only a 10% increase in survival probability at 12 months (HR: 0.91; 95%CI: 0.44-1.89; p = 0.9). CONCLUSIONS: In this population-based series, we found that in Southern Italy management of ALS by multidisciplinary clinics does not improve survival, regardless of site of symptoms onset.

A case of vacuolar myopathy during the course of chronic hepatitis C.

Several cases of inflammatory myopathy have been reported during the chronic course of hepatitis C (HC) in recent years. It has been suggested that this muscular inflammatory involvement in HC is related to an immune-mediated mechanism caused by the hepatitis C virus (HCV), as HCV RNA has been detected in the muscle of patients with concomitant inflammatory myopathy and chronic HC. Herein, we report on a patient with a history of chronic HC, who developed a slowly progressive proximal muscle weakness; muscle biospy revealed a vacuolar myopathy. Histological, immunohistochemical and biochemical study did not disclose any known cause of vacuolar myopathy. To our knowledge, this is the first report of a vacuolar myopathy during the course of HC. We suggest that it may be opportune to include HC among the possible aetiologies of vacuolar myopathy, should other reports confirm this association.

Predictors of delay in the diagnosis and clinical trial entry of amyotrophic lateral sclerosis patients: a population-based study.

BACKGROUND: The El Escorial and the revised Airlie House diagnostic criteria for amyotrophic lateral sclerosis (ALS) were introduced to select patients for clinical trials. Heterogeneity of clinical presentation at onset and delay in diagnosis may decrease the likelihood for trial entry. OBJECTIVE: Identify risk factors for delay in the diagnosis and trial exclusion. METHODS: ALS incident cases were identified with El Escorial (EEC) and Airlie House criteria (AHC) through a population-based registry established in Puglia, Southern Italy, in the years 1998-99. RESULTS: 130 ALS incident cases were diagnosed with a median interval between onset of symptoms and diagnosis of 9.3 months and not different across both EEC and AHC categories. Twenty percent of cases were not eligible for clinical trials according to the AHC. About 5% of subjects in this series died with only lower motor neuron signs. Predictors for delay in the diagnosis were age between 65 and 75 years and spinal onset while fasciculations and cramps as first symptoms were predictors of exclusion from trials. CONCLUSIONS: In this population-based series, diagnostic delay was longer in subjects with spinal onset and age between 65 and 75 and fasciculation as first symptoms. About 80% of incident cases were trial eligible with AHC criteria. However, a significant number of subjects with ALS, characterized by a limited spread of signs, were not trial eligible while alive.

Unusual clinical presentation of a patient carrying a novel single 1.8 kb deletion of mitochondrial DNA.

Kearns-Sayre syndrome (KSS) is a mitochondrial encephalomyopathy characterized by progressive external ophthalmoplegia (PEO), pigmentary retinopathy and onset before the age of 20 years. Cerebellar ataxia, as well as short stature and increased protein content in the cerebrospinal fluid, are frequent additional symptoms. A single large mitochondrial (mt) DNA deletion of 4,977 bp is the most common molecular defect in KSS. Recently, different mutations have also been associated with incomplete, KSS-like phenotypes. We describe the unusual clinical presentation of a patient carrying a novel 1,814-bp deletion of mtDNA. In contrast with typical KSS, the clinical picture of this patient did not include either palpebral ptosis or PEO and was dominated by an ataxic syndrome.