Elevated IL-4 and IFN-γ Levels in Muscle Tissue of Patients with Dermatomyositis.

Background/aim: To investigate the contribution of muscle tissue-derived cytokines in dermatomyositis (DM).

Materials And Methods: Muscle homogenates were prepared from deltoid muscle biopsy specimens of 10 patients with DM and eight controls with no pathological signs of myopathy. Interleukin (IL)-4, interferon (IFN)-γ and IL-17 levels were evaluated by enzyme-linked immunosorbent assay (ELISA) and immunoblotting analysis.

Dental follicle mesenchymal stem cell administration ameliorates muscle weakness in MuSK-immunized mice.

Background: Myasthenia gravis (MG) is an antibody-mediated autoimmune disease of the neuromuscular junction (NMJ), mostly associated with acetylcholine receptor (AChR) antibodies. Around 5-10 % of MG patients show antibodies to muscle-specific tyrosine kinase (MuSK). Mesenchymal stem cell (MSC) administration has been shown to ameliorate muscle weakness in the experimental autoimmune myasthenia gravis (EAMG) model induced by AChR immunization.

Reduced muscle mitochondrial enzyme activity in MuSK-immunized mice.

Aim: Muscle specific kinase (MuSK) antibody-positive myasthenia gravis(MG) patients might present with clinical and electrophysiological signs of muscle atrophy. In this study, we investigated the potential contribution of mitochondrial dysfunction to muscle atrophy induced by MuSK immunity.

Methods: Mitochondrial enzyme expression was investigated in muscle samples of MuSK-immunized, acetylcholine receptor (AChR)-immunized, and complete Freund's adjuvant (CFA)-immunized C57BL/6 (B6) mice using histochemical methods.

Mitochondrial pathology in muscle of a patient with a novel parkin mutation.

Mutations of the parkin gene on chromosome 6 cause early-onset parkinsonism. Myopathy has not been reported to be a feature of this condition. Here we report the muscle biopsy findings of a 53-year-old man with a novel parkin gene mutation (IVS-9-1 deletion).