Differential expression of the IL-1 system components during in vitro myogenesis: implication of IL-1beta in induction of myogenic cell apoptosis.

We evaluated the expression of IL-1 system by normal human myogenic cells during in vitro myogenesis and the effect of exogenous IL-1beta. Expression of IL-1alpha and beta, IL-1 receptor antagonist (IL-1Ra), IL-1RI and II, IL-1R accessory protein (IL-1RAcP) and IL-1beta converting enzyme (ICE) was studied by immunocytochemistry, immunoblotting, ELISA and RT - PCR. Cell proliferation was evaluated by [3H]thymidine incorporation, cell fusion by flow cytometry and cell death by in situ end-labelling.

Choreic movements and MRI abnormalities in the subthalamic nuclei reversible after administration of coenzyme Q10 and multiple vitamins in a patient with bilateral optic neuropathy.

A 37-year-old man developed choreic movements of the limbs over a few months. His medical history included bilateral visual loss detected at the age of 9 and worsening at age 20. Visual field testing showed a central scotoma.

Zidovudine-induced mitochondrial disorder with massive liver steatosis, myopathy, lactic acidosis, and mitochondrial DNA depletion.

Zidovudine is known to be responsible for a mitochondrial myopathy with ragged-red fibres and mitochondrial DNA depletion in muscle. Lactic acidosis alone or associated with hepatic abnormalities has also been reported. A single report mentioned the concomitant occurrence of muscular and hepatic disturbances and lactic acidosis in a patient receiving zidovudine, but muscle and liver tissues were not studied.

Myoglobin as a polymerase chain reaction (PCR) inhibitor: a limitation for PCR from skeletal muscle tissue avoided by the use of Thermus thermophilus polymerase.

Skeletal muscle tissue contains polymerase chain reaction (PCR) inhibitors that are coextracted by conventional nucleic acid extraction procedures. Myoglobin, a heme-containing molecule, was shown to act as a potent Thermus aquaticus DNA polymerase inhibitor and is likely to be involved in muscle tissue-associated PCR inhibition. The use of Thermus thermophilus DNA polymerase avoids muscle tissue-associated PCR inhibition, and should be used in case of small amounts or instability of the targeted nucleic acid.

Interleukin-1 expression in normal motor endplates and muscle fibers showing neurogenic changes.

Histological features of neurogenic muscle involvement include type grouping, muscle fiber atrophy and target fibers. In zidovudine-induced myopathy and dermatomyositis, immunoreactivity for interleukin (IL)-1 has been reported in diseased muscle fibers involving myofibrillar breakdown and atrophy. Since IL-1 is a signal for muscle proteolysis, we studied myofiber expression of IL-1 in neurogenic muscle involvement, specially in atrophic myofibers and target fibers which are associated with myofilament breakdown.