The clinical data from 104 medical records who met both clinical and genetic criteria for Duchenne (DMD) and Becker muscular dystrophy (BMD) attending a multidisciplinary clinic in a single medical center in Israel is presented. Data was analyzed and sub divided into ambulatory (ADMD), non-ambulatory DMD (NADMD) and BMD. Clinical data including 6 Min Walk Test (6MWT) and North Star Ambulatory Assessment (NSAA) were recorded. The cohort was comprised of 57 ADMD boys (54.8%); average age 9.3±3.1, 23 NADMD children (22.1%); average age: 15.8±4, and 24 BMD children (23.1%); average age; 11.5±4.9. Age of diagnosis for DMD patients was 3.75±1.9 years and their loss ambulation age was 11±2.7 years. Sixty-three of the entire cohort of DMD children (78.7%) were treated with steroids; 46/57 of ADMD (80.7%) and 17/23 NADMD (73.9%). Among all DMD patients (n=80) 53 (66.2%) were treated with prednisone/prednisolone, 8 (10%) with deflazacort and 3 (3.7%) with vamorolone. BMD patients had higher 6MWT and NSAA scores compared to ambulatory DMD (6MWT:.501.1±76.7m vs. 380.1±93.m; NSAA: 31.4±93.5 vs. 24.4±5.4, p=0.001). ADMD had significantly higher CPK level compared to NADMD and BMD (ADMD: 11,073±6661mg/dl; NADMD: 3386±3255 mg/dl; BMD: 3659±3408 mg/dl, p<0.001). In addition, BMD patients had a lower resting heart rate compared to ADMD (BMD: 83.2±13.5 bpm; ADMD: 98.2±12.7 bpm, p<0.001). No significant differences were found between the groups in resting systolic blood pressure and diastolic blood pressure parameters. A significant lower level of %FEV1 was detected in NADMD compared to ADMD and BMD (NADMD: 59±16.4%; ADMD: 93.5±10.7%; BMD: 98.8±8.1% p<0.001). Significant correlations were found between 6MWT and NSAA in ADMD (r=0.67; p<0.0001) and in BMD (r=0.76; p=0.001). The current data represents the clinical characteristics and management data of DMD and BMD children in Israel.

Small fiber neuropathy affecting the small A δ and C fibers is rare in children. Few data have been published on the etiology of small fiber neuropathy in the pediatric population. Metabolic, infectious, and toxic causes were described. It has been associated with several autoimmune disorders such as Sjogren disease, fibromyalgia and celiac disease, but there are no reports of an autoinflammatory etiology. The aim of the present study was to highlight the potential etiologic role of autoinflammatory syndromes, particularly familial Mediterranean fever, in small fiber neuropathy and erythromelalgia in the pediatric population. The data of four children presenting with erythromelalgia and neuropathic pain were collected retrospectively from the electronic database of a pediatric medical center. Clinical and electrophysiologic evaluation excluded large nerve fiber involvement. Skin biopsies confirmed small-fiber neuropathy. On genetic analysis, 2 children were homozygous and one was heterozygous for familial Mediterranean fever-associated MEFV mutations. The fourth child was diagnosed with Behcet disease. Treatment with anti-interleukin-1, intravenous immunoglobulin, and glucocorticoid was beneficial. The diagnosis of small- fiber neuropathy should be considered in children presenting with erythromelalgia. A thorough investigation is needed to reveal the underlying disorder. Clinicians should be alert to the peripheral neurological manifestations of autoinflammatory syndromes because effective treatments are available.

Neuromyelitis optica (NMO) and myasthenia gravis (MG) are autoimmune diseases mediated by autoantibodies against either aquaporin 4 (AQP4) or acetylcholine receptor (AChR), respectively. Recently, we and others have reported an increased prevalence of NMO in patients with MG. To verify whether coexisting autoimmune disease may exacerbate experimental autoimmune MG, we tested whether active immunization with AQP4 peptides or passive transfer of NMO-Ig can affect the severity of EAMG. Injection of either AQP4 peptide or NMO-Ig to EAMG or to naive mice caused increased fatigability and aggravation of EAMG symptoms as expressed by augmented muscle weakness (but not paralysis), decremental response to repetitive nerve stimulation, increased neuromuscular jitter, and aberration of immune responses. Thus, our study shows increased disease severity in EAMG mice following immunization with the NMO autoantigen AQP4 or by NMO-Ig, mediated by augmented inflammatory response. This can explain exacerbation or increased susceptibility of patients with one autoimmune disease to develop additional autoimmune syndrome.

Duchenne muscular dystrophy (DMD) caused by mutations in Dystrophin gene and congenital muscular dystrophy type 1A (MDC1A) caused by mutations in LAMA2, are incurable childhood forms of muscular dystrophy. Although both disorders result from mutations in proteins strengthening the muscle sarcolemma, they are implicated in clinically distinct phenotypes. We used RNA deep sequencing (RNA-Seq) of dy2J/dy2J, MDC1A mouse model, skeletal muscle to elucidate disease pathophysiology. This study is the first report of comparing the transcriptome profile of dy2J/dy2J mouse model to WT. RNA-Seq of the mdx mouse model of DMD and its control was carried as well in order to enable a comparison of the two mouse models. 3844 genes were significantly differentially expressed in mdx versus WT mice (2695 upregulated and 1149 downregulated, FDR (false detection rate) < 0.05) and 2675 genes in dy2J/dy2J versus WT (1727 upregulated and 948 downregulated, FDR < 0.05). 1834 common differentially expressed genes between mdx and dy2J/dy2J were found (1285 upregulated and 549 downregulated, FDR < 0.05). Enrichment pathway analysis using Ingenuity Pathway Analysis (IPA) software of the common differentially expressed genes showed enrichment of inflammation, fibrosis, adhesion, apoptosis, muscle cell structure and metabolism (p-values 3E-10 – 9E-37). Canonical pathways, such as ILK, NF-kB, Wnt, calcium signaling and others were found to be enriched in both models (FDR < 0.05). Our data deepen our understanding of the molecular pathophysiology of each disease in order to select new pathways or targets for additional therapies in CMD and DMD.

Corticosteroids, the only treatment with proven efficacy in Duchenne muscular dystrophy (DMD) are associated with severe side effects. Here, in a proof of concept study nano-sterically stabilized liposomes (NSSL), remote loaded with methylprednisolone (MPS), were selectively targeted to the diaphragm, the mdx affected muscle at the early stage of the disease. The bioactivity of NSSL-MPS was evidenced by significant decreased serum TGF-β level and reduced diaphragm macrophage infiltration similar to free-MPS. Free-MPS (5 mg/kg) and two doses of NSSL-MPS (2 and 5 mg/kg) were tested for long-term treatment (58 weeks). All MPS treated groups had significantly lower CPK levels compared with control mdx mice. 2 mg/kg NSSL-MPS treatment resulted in significantly improved fore-limb muscle strength compared to free-MPS and control mdx mice. 5 mg/kg NSSL-MPS significantly improved animal mobility compared to control mdx mice. Treatment with the free-MPS has a clear bone catabolic effect; decrease in trabecular bone-volume density (BV/TV), deterioration in the trabecular number (Tb.N), as well as a significant decrease in the trabecular connectivity density (Conn.D) of the tibia bone. These were mitigated by both NSSL-MPS doses. Treatment with both doses produced a significant increase in BV/TV values compared with the mdx free-MPS group. 2 mg/kg NSSL-MPS treatment resulted in significantly increased Tb.N and Conn.D compared to free-MPS mice, indicating increase in micro-architectural structure's strength. Treatment with both NSSL-MPS doses significantly increased Conn.D, Tb.N and decreased trabecular spacing in comparison with the control and the free-MPS group, but had no effect on the BV/TV of lumbar vertebra 3 (L3), indicating an increase in the micro-architectural structure's strength also in mdx L3 bone. The results of this study suggest that NSSL-MPS is superior to free-MPS in treatment efficacy and reduced osteoporosis in the mdx mouse model of DMD.

The objective of the study was to evaluate the epidemiology of patients with congenital myasthenic syndrome (CMS) in Israel. Targeted mutation analysis was performed based on the clinical symptoms and electrophysiological findings for known CMS. Additional specific tests were performed in patients of Iranian and/or Iraqi Jewish origin. All medical records were reviewed and clinical data, genetic mutations and outcomes were recorded. Forty-five patients with genetic mutations in known CMS genes from 35 families were identified. Mutations in RAPSN were identified in 13 kinships in Israel. The most common mutation was c.-38A>G detected in 8 patients of Iranian and/or Iraqi Jewish origin. Four different recessive mutations in COLQ were identified in 11 kinships, 10 of which were of Muslim-Arab descent. Mutations in CHRNE were identified in 7 kinships. Less commonly detected mutations were in CHRND, CHAT, GFPT1 and DOK7. In conclusion, mutations in RAPSN and COLQ are the most common causes of CMS in our cohort. Specific mutations in COLQ, RAPSN, and CHRNE occur in specific ethnic populations and should be taken into account when the diagnosis of a CMS is suspected.

Inflammation and fibrosis are well-defined mechanisms involved in the pathogenesis of the incurable Laminin α 2-deficient congenital muscular dystrophy (MDC1A), while apoptosis mechanism is barely discussed. Our previous study showed treatment with Losartan, an angiotensin II type I receptor antagonist, improved muscle strength and reduced fibrosis through transforming growth factor beta (TGF- β ) and mitogen-activated protein kinases (MAPK) signaling inhibition in the dy 2J /dy 2J mouse model of MDC1A. Here we show for the first time that Losartan treatment up-regulates and shifts the nuclear factor kappa B (NF κ B) signaling pathway to favor survival versus apoptosis/damage in this animal model. Losartan treatment was associated with significantly increased serum tumor necrosis factor alpha (TNF- α ) level, p65 nuclei accumulation, and decreased muscle IκB- β protein level, indicating NF κ B activation. Moreover, NF κ B anti-apoptotic target genes TNF receptor-associated factor 1 ( TRAF1 ), TNF receptor-associated factor 2 ( TRAF2 ), cellular inhibitor of apoptosis ( cIAP2 ), and Ferritin heavy chain ( FTH1 ) were increased following Losartan treatment. Losartan induced protein expression toward a pro-survival profile as BCL-2 expression levels were increased and Caspase-3 expression levels were decreased. Muscle apoptosis reduction was further confirmed using terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling (TUNEL) assay. Thus, along with TGF- β and MAPK signaling, NF κ B serves as an important regulatory pathway which following Losartan treatment promotes survival in the dy 2J /dy 2J mouse model of MDC1A.

The objective of the present study was to elucidate the molecular basis of a new clinical entity of childhood familial immune mediated relapsing polyneuropathy associated with chronic Coombs-negative hemolysis. Since infancy these children had recurrent episodes of weakness and hemolysis with partial improvement following immune modulating therapy. One child died at the age of 3.5 years while the others demonstrated severe lower limb paralysis. A founder mutation was searched for using homozygosity mapping followed by exome sequencing in 5 infants of North-African Jewish origin from 4 unrelated families. The expression of CD59, CD55, and CD14 was examined in blood cells by flow cytometry followed by Western blot of the CD59 protein. Homozygous missense mutation, p.Cys89Tyr in CD59, was identified in all patients. The mutation segregated with the disease in the families and had a carrier rate of 1:66 among Jewish subjects of North-African origin. The mutated protein was present in the patients’ cells in reduced amounts and was undetectable on the membrane surface. CD59 deficiency is a common finding in RBCs and WBCs in patients with chronic hemolysis suffering from paroxysmal nocturnal hemoglobinuria in which the acquired mutation in the PIGA gene leads to membrane loss of glycosylphosphatidylinositol-anchored membrane proteins, including CD59. Based on the results of the present study, we suggest that the Cys89Tyr mutation in CD59 is associated with a failure of proper localization of the CD59 protein in the cell surface and decreased complement inhibition. This mutation is manifested clinically in infancy by relapsing peripheral demyelinating disease and chronic hemolysis. The objective of the present study was to elucidate the molecular basis of a new clinical entity of childhood familial immune mediated relapsing polyneuropathy associated with chronic Coombs-negative hemolysis. Since infancy these children had recurrent episodes of weakness and hemolysis with partial improvement following immune modulating therapy. One child died at the age of 3.5 years while the others demonstrated severe lower limb paralysis. A founder mutation was searched for using homozygosity mapping followed by exome sequencing in 5 infants of North-African Jewish origin from 4 unrelated families. The expression of CD59, CD55, and CD14 was examined in blood cells by flow cytometry followed by Western blot of the CD59 protein. Homozygous missense mutation, p.Cys89Tyr in CD59, was identified in all patients. The mutation segregated with the disease in the families and had a carrier rate of 1:66 among Jewish subjects of North-African origin. The mutated protein was present in the patients’ cells in reduced amounts and was undetectable on the membrane surface. CD59 deficiency is a common finding in RBCs and WBCs in patients with chronic hemolysis suffering from paroxysmal nocturnal hemoglobinuria in which the acquired mutation in the PIGA gene leads to membrane loss of glycosylphosphatidylinositol-anchored membrane proteins, including CD59. Based on the results of the present study, we suggest that the Cys89Tyr mutation in CD59 is associated with a failure of proper localization of the CD59 protein in the cell surface and decreased complement inhibition. This mutation is manifested clinically in infancy by relapsing peripheral demyelinating disease and chronic hemolysis.

The dy2J/dy2J mouse model of lamininα2-deficient congenital muscular dystrophy (MDC1A) has prominent peripheral neuropathy with slowed conduction. The conduction slowing may be due to reduced myelinated axon number, diameter, and atypical Schwann cell ensheathement/amyelination with aberrant basal lamina, nodal gap shortening, and decreased axon membrane excitability. Although no inflammatory mechanism was identified in dy2J/dy2J neuropathy, other genetically mediated neuropathies show low-grade inflammation and immune pathways play a pathological role. The immune modulating agent, Glatiramer acetate (GA) improves dy2J/dy2J mouse mobility and hind limb muscle strength, and shows significant beneficial effect in the neuropathy of experimental autoimmune neuritis (EAN). GA mechanisms of action from experimental autoimmune encephalomyelitis (EAE) and multiple sclerosis studies are at various levels of the immune response (skewing T-cells from pro- to anti-inflammatory pathways) and generating neuroprotective activity (brain derived neurotrophic factor BDNF, anti-inflammatory cytokines). Because of GA’s beneficial effect in the dy2J/dy2J mouse model we evaluated it’s effect on dy2J/dy2J peripheral neuropathy motor conduction. Homozygous dy2J/dy2J and control mice were treated with GA or placebo for 12 weeks from 6 weeks of age. Outcome measures included sciatic-posterior tibial motor nerve conduction parameters (NCV, distal latency, and CMAP amplitude, area and dispersion) at 18 weeks. GA treated dy2J/dy2J mice showed significantly improved average sciatic-posterior tibial nerve motor conduction velocity 50.35 ± 2.9 m/s versus untreated dy2J/dy2J 34.49 ± 2.14 m/s (p < 0.001), WT controls 63.04 ± 2.33 m/s. Glatiramer acetate significantly improved motor nerve conduction velocity (NCV) in the dy2 J/dy2J mouse model of congenital muscular dystrophy. The dy2J/dy2J mouse model of lamininα2-deficient congenital muscular dystrophy (MDC1A) has prominent peripheral neuropathy with slowed conduction. The conduction slowing may be due to reduced myelinated axon number, diameter, and atypical Schwann cell ensheathement/amyelination with aberrant basal lamina, nodal gap shortening, and decreased axon membrane excitability. Although no inflammatory mechanism was identified in dy2J/dy2J neuropathy, other genetically mediated neuropathies show low-grade inflammation and immune pathways play a pathological role. The immune modulating agent, Glatiramer acetate (GA) improves dy2J/dy2J mouse mobility and hind limb muscle strength, and shows significant beneficial effect in the neuropathy of experimental autoimmune neuritis (EAN). GA mechanisms of action from experimental autoimmune encephalomyelitis (EAE) and multiple sclerosis studies are at various levels of the immune response (skewing T-cells from pro- to anti-inflammatory pathways) and generating neuroprotective activity (brain derived neurotrophic factor BDNF, anti-inflammatory cytokines). Because of GA’s beneficial effect in the dy2J/dy2J mouse model we evaluated it’s effect on dy2J/dy2J peripheral neuropathy motor conduction. Homozygous dy2J/dy2J and control mice were treated with GA or placebo for 12 weeks from 6 weeks of age. Outcome measures included sciatic-posterior tibial motor nerve conduction parameters (NCV, distal latency, and CMAP amplitude, area and dispersion) at 18 weeks. GA treated dy2J/dy2J mice showed significantly improved average sciatic-posterior tibial nerve motor conduction velocity 50.35 ± 2.9 m/s versus untreated dy2J/dy2J 34.49 ± 2.14 m/s (p < 0.001), WT controls 63.04 ± 2.33 m/s. Glatiramer acetate significantly improved motor nerve conduction velocity (NCV) in the dy2 J/dy2J mouse model of congenital muscular dystrophy.