calpain and Eosinophilia

Topics: Animals; Calpain; Child; Diagnosis, Differential; Eosinophilia; Humans; Muscle Proteins; Muscular Diseases; Mutation; Myositis

Topics: Adult; Calpain; Eosinophilia; Eosinophils; Humans; Male; Muscle Proteins; Muscular Dystrophies, Limb-Girdle; Mutation, Missense

Topics: Adult; Calpain; Child; Child, Preschool; Eosinophilia; Eosinophils; Female; Humans; Male; Muscle Proteins; Muscle, Skeletal; Muscular Dystrophies, Limb-Girdle; Mutation; Myositis

We recently showed that poly(ADP-ribose)polymerase-1 (PARP-1) may play a role in allergen (ovalbumin)-induced airway eosinophilia, potentially through a specific effect on IL-5 production. We also reported that while IL-5 replenishment promotes reversal of eosinophilia in lungs of PARP-1(-/-) mice, IL-4 or Immunoglobulin E replenishment do not, suggesting a potentially significant regulatory relationship between PARP-1 and IL-5.. To explore the mechanism by which PARP-1 regulates IL-5 production and to determine how PARP-1 inhibition blocks allergen-induced eosinophilia.. This study was conducted using a murine model of allergic airway inflammation and primary splenocytes.. PARP-1 knockout-associated reduction in IL-5 upon allergen exposure occurs at the mRNA level. Such an effect appears to take place after IL-4 receptor activation as PARP-1 inhibition exerted no effect on JAK1/JAK3 activation. Signal transducer and activator of transcription-6 (STAT-6) protein was severely downregulated in spleens of PARP-1(-/-) mice without any effect on mRNA levels, suggesting an effect on protein integrity rather than gene transcription. Interestingly, the degradation of STAT-6 in PARP-1(-/-) mice required allergen stimulation. Additionally, PARP-1 enzymatic activity appears to be required for STAT-6 integrity. The downregulation of STAT-6 coincided with mRNA and protein reduction of GATA-binding protein-3 and occupancy of its binding site on the IL-5 gene promoter. IL-4 was sufficient to induce STAT-6 downregulation in both PARP-1(-/-) mice and isolated splenocytes. Such degradation may be mediated by calpain, but not by proteasomes.. These results demonstrate a novel function of PARP-1 in regulating IL-5 expression during allergen-induced inflammation and explain the underlying mechanism by which PARP-1 inhibition results in IL-5 reduction.

Topics: Allergens; Animals; Asthma; Calpain; Disease Models, Animal; Eosinophilia; Female; Humans; Inflammation; Interleukin-5; Male; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Knockout; Poly (ADP-Ribose) Polymerase-1; Poly(ADP-ribose) Polymerases; Respiratory System; STAT6 Transcription Factor

Topics: Adult; Aged; Biopsy; Calpain; DNA Mutational Analysis; Eosinophilia; Female; Humans; Muscle Proteins; Muscle, Skeletal; Neurologic Examination; Polymyositis

Mutations in the gene encoding calpain-3 (CAPN3) cause autosomal recessive limb-girdle muscular dystrophy type 2A (LGMD2A) and idiopathic eosinophilic myositis. Accurate diagnosis and genetic counselling are based on the identification of disease-causing mutations on both alleles of CAPN3 in the patients. In the present study, we used transcriptional analysis as a complementary approach for patients suspected of being affected with LGMD2A, in whom initial denaturing high-performance liquid chromatography genomic mutation screening evidenced no or only one CAPN3 mutation obviously considered as disease causing. This allowed to identify and characterize cDNA deletions. Further genomic analysis allowed to determine the origin of these deletions, either as splicing defects caused by intronic mutations or as an internal multi-exonic deletion. In particular, we report two novel CAPN3 mutations (c.1745 + 4_1745 + 7delAGTG in IVS13 and c.2185-16A>G in IVS20) and a recurrent large-sized genomic deletion including exons 2-8 for which genomic breakpoints have been characterized. In addition, our results indicate nonsense-mediated messenger RNA decay as a mechanism for under-expression of CAPN3 associated to some specific variations.

Topics: Adolescent; Adult; Aged; Base Sequence; Calpain; DNA Primers; Eosinophilia; Female; Humans; Male; Middle Aged; Muscle Proteins; Muscular Dystrophies, Limb-Girdle; Mutation; Myositis; RNA Splicing; RNA Stability; RNA, Messenger; Sequence Deletion; Transcription, Genetic

Eosinophilic myositis (EM) constitutes a rare pathological entity characterized by eosinophilic infiltration of skeletal muscles, usually associated with parasite infections, systemic disorders, or the intake of drugs or L-tryptophan. The exclusion of such causes defines the spectrum of idiopathic EM. Based on a protein analysis performed in one affected patient, we identified the gene encoding calpain-3, CAPN3, as a candidate for a subset of idiopathic EM.. We screened CAPN3 for mutations using DHPLC and direct sequencing in six unrelated patients, recruited for EM diagnosed after histological examination of muscle biopsy samples, without any identified causative factor.. We identified CAPN3 mutations in the six unrelated patients originally diagnosed with idiopathic EM.. Mutations in CAPN3 can cause EM. Thus, a subset of idiopathic EM is genetically determined, with an autosomal recessive mode of inheritance. Patients presented with a triad that appears to be indicative of CAPN3 mutations: (1) EM in the first decade, (2) elevated serum creatine phosphokinase levels (isolated or with little corresponding weakness), and (3) inconstant peripheral hypereosinophilia. However, that EM represents a distinct phenotype associated to CAPN3 mutations or, rather, an early histopathological picture of LGMD2A must be further evaluated. Our findings should be of interest toward further investigating the role of calpain-3 in skeletal muscle. Furthermore, patients with idiopathic EM should undergo calpain-3 protein analysis and be considered for subsequent molecular analysis of the CAPN3 gene.

Topics: Blotting, Western; Calpain; Child; Child, Preschool; Creatine Kinase; Eosinophilia; Female; Genetic Predisposition to Disease; Humans; Immunohistochemistry; Male; Muscle Proteins; Mutation; Myositis; Polymerase Chain Reaction