Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0231528 (myalgia)
 6,565 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

194 clinical, laboratory, electrophysiologic, histological, histochemical and immunohistochemical parameters were studied through statistical analysis in 112 cases of Duchenne muscular dystrophy (DMD) and in 26 cases of Becker muscular dystrophy (BMD). It was found a significant statistical difference (p < 0.05) between the two groups concerning the age of evaluation, beginning of symptoms, difficulty in walking, running, climbing and going downstairs, frequent falling down, support to walk, localized muscle pain, stopping climb stairs, and inability to walk. Muscle biopsy showed statistically significant (p < 0.05) differences between the two groups regarding the intensity of connective tissue and focal adipose tissue proliferation, presence of diffuse rounded atrophic and angulated fibers, diffuse hypertrophic and splitting fibers. There were also differences regarding excessive internal fibers nuclei, hypertrophic types 1 and 2 fibers, angulated atrophic fibers and focal increasing in the NADH-TR, angulated atrophic fibers in non-specific esterase, and accumulated NBT in the periphery of fibers in succinic dehidrogenase. Isolatedly muscle biopsy gave the correct diagnosis in 52.7% of DMD cases and in 69.2% of BMD cases. Dystrophin detection by immunofluorescence (60 cases) showed: absence in 87.0% of fibers in DMD cases, and sarcolemmal membrane discontinuites in all BMD cases. The muscle biopsy diagnosis had an agreement with the dystrophin results in 82.6% of DMD cases and 71.4% of BMD cases.
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PMID:[Early differentiation between Duchenne and Becker muscular dystrophy: clinical, laboratory, electrophysiology, histochemical, and immunohistochemical study of 138 cases]. 130 51

Glycolysis is an important energy productive system. Enzyme abnormalities the in glycolytic pathway, which cause myoglobinuria, are deficiencies of phosphofructokinase, phosphoglycerate kinase, phosphoglycerate mutase, and lactate dehydrogenase (LDH). Common symptoms of these enzyme abnormalities are muscle cramp, muscle pain, and rhabdomyolysis after strenuous exercise. Acute renal failure owing to myoglobinuria is the most noteworthy symptom. In daily life, symptoms are rarely observed and prognosis is usually good. Correct and fast diagnosis of such latent symptomatic disorders is important to prevent a turn for the worse of these symptoms. LDH M subunit deficiency was first discovered by urinary discoloration and a discrepancy of laboratory data. Since then, only four cases have been reported in the Japanese population. The response to ischemic forearm work is characteristic (an increase of venous lactate concentration after ischemic work is not observed and a marked increase of venous pyruvate is found). The increase of pyruvate concentration is specific in LDH-M subunit deficiency, and is not observed in other abnormalities of the glycolytic pathway. Glycolysis was markedly retarded in the patient's muscle in the glyceraldehyde 3-phosphate dehydrogenase (GA3PD) step, possibly due to the impaired reoxidation of NADH produced by GA3PD activity. Then, the excess NADH is reoxidized by alpha-glycerophosphate dehydrogenase and triose phosphates are drained to alpha-glycerophosphate and glycerol. Therefore ATP production is significantly impaired and muscle tissue is damaged. A genetical study revealed a deletion of 20 base-pairs in exon 6 in LDH-M subunit deficiency. This mutation results in a frame-shift translation and premature termination.
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PMID:[Myoglobinuria due to enzyme abnormalities in glycolytic pathway--especially lactate dehydrogenase M subunit deficiency]. 182 77

A case of 16-year-old female with myalgia and myoglobinuria following prolonged exercise was reported. Neurological examination revealed mild weakness of proximal muscle in the lower extremities. Serum CK, LDH, myoglobin were significantly increased during the attacks. On biopsy, the muscle fibers contained myriad lipid-filled vacuoles, in predominantly type 1 fibers. Electron microscope examinations revealed numerous lipid droplets adjacent to mitochondria and glycogen particles. Carnitine level in the patient's muscle was markedly reduced (under 5% of control), but the serum carnitine concentration was normal. The muscle carnitine palmityl transferase level was not depressed. A forearm ischemic test resulted in normal lactate production. On exercise tolerance test by a bicycle ergometer, mild exercise (15-30 watts for 15 minutes) induced myalgia and marked elevation in serum CK, lactate and pyruvate, while severe exercise showed no increase in serum CK level. The findings suggest that the energy production system in the skeletal muscle was impaired. However, the enzyme activities of NADH oxidation in mitochondria and the anaerobic glycolysis pathway were within normal limits. During fasting (36 hours), there was a normal production of ketone bodies, suggesting that hepatic metabolism of lipids was normal. She showed good response to L-carnitine therapy.
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PMID:[Muscle carnitine deficiency associated with myalgia and rhabdomyolysis following exercise]. 274 89

Three patients with chronic progressive external ophthalmoplegia of adult-onset, generalized muscle atrophy and myalgia are described. Two patients fulfilled the histological criteria for centronuclear myopathy, the third those for fiber-type disproportion. Additionally, typical ragged red fibers were found in all muscle specimens, and several muscle fibers were cytochrome c oxidase negative. NADH and succinate dehydrogenase stains showed increased subsarcolemmal accumulation of mitochondria. To determine whether these findings are coincidental or whether they indicated an additional mitochondrial disorder, all patients were investigated using biochemical analysis of the respiratory chain, molecular genetics, magnetic resonance spectroscopy of quadriceps muscle and ergometry. These tests suggested an additional mitochondrial dysfunction. Mitochondrial dysfunction seems to be more common in this group of myopathies than previously estimated, and may be of importance in the pathogenesis of these disorders.
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PMID:Mitochondrial dysfunction in adult-onset myopathies with structural abnormalities. 773 87

Although disorders of thyroid function may cause a wide range of muscle disturbances, an overt myopathy has been rarely reported as an isolated clinical presentation of hypothyroidism. We observed 10 patients (5 males and 5 females) who had been referred to the department of neurology because of muscular fatigability, myalgia, cramps, or proximal weakness. Laboratory investigation showed that all patients had hypothyroidism due to Hashimoto's thyroiditis (atrophic variant in 9/10). Classic symptoms/signs of hypothyroidism such as lethargy, constipation, cold intolerance, myxedematous facies, and/or bradycardia were absent, as assessed independently by the three coauthoring thyroidologists. Muscular complaints improved greatly and then disappeared after substitutive levothyroxine treatment. Muscle biopsy revealed nonspecific changes. Nicotinamide adenine dinucleotide reductase (NADH-TR)-hyporeactive cores were present in two patients (10% and 90% of type 1 fibers). On electron microscopy, the core areas showed disorganized myofibrils, Z-band streaming, rod formation, and paucity of mitochondria and glycogen granules. Desmin intermediate filaments were overexpressed only in some cores. The similarity of the pattern of desmin expression between hypothyroid cores and target lesions of denervated fibers supports the hypothesis that, at least in some of our patients, myopathy was the result of an impaired nerve-mediated action of thyroid hormones on skeletal muscle. Our observations suggest that an isolated myopathy as the sole manifestation of hypothyroidism is not a rare event. We postulate that our cases may constitute a peculiar subgroup of Hashimoto's thyroiditis patients: (1) the strikingly abnormal F/M ratio of 1:1; (2) the relatively younger age; (3) the rarity of the goitrous variant; (4) the unusual finding of antithyroglobulin (Tg-Ab) > antithyroid peroxidase (TPO-Ab). Thorough evaluation of thyroid function is appropriate in patients with myopathy of uncertain origin.
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PMID:Myopathy as the persistently isolated symptomatology of primary autoimmune hypothyroidism. 984 19

Statin drugs represent the major improvement in the treatment of hypercholesterolemia that constitutes the main origin of atherosclerosis, leading to coronary heart disease. Besides tremendous beneficial effects of statins, various forms of muscular toxicity (myalgia, cramp, exercise intolerance, and fatigability) occur frequently. We hypothesized that the iatrogenic effects of statins could result from alterations in Ca(2+) homeostasis. Acute applications of simvastatin on human skeletal muscle fibers triggered a Ca(2+) wave of intra-cellular Ca(2+) that mostly originates from sarcoplasmic reticulum (SR) Ca(2+)-release. In addition, simvastatin increased mitochondrial NADH content and induced mitochondrial membrane depolarization (EC(50)=1.96 microM) suggesting an altered mitochondrial function. Consequently on simvastatin application, a weak mitochondrial Ca(2+) efflux (EC(50)=7.8 microM) through permeability transient pore and Na(+)/Ca(2+) exchanger was triggered, preceding the large SR-Ca(2+) release. Increased SR Ca(2+) content after acute application of statin is also suggested by the increased Ca(2+) spark amplitude and by the effect of cyclopiazonic acid. We thus conclude that simvastatin induced alterations in mitochondrial function which lead to an increase in cytoplasmic Ca(2+), SR-Ca(2+) overload, and Ca(2+) waves. Taken together, these statin-induced muscle dysregulations may contribute to myotoxicity.
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PMID:Simvastatin triggers mitochondria-induced Ca2+ signaling alteration in skeletal muscle. 1575 63

Active skeletal muscles produce lactate. H+ is generated during lactate neutralization in the Cori cycle, which leads to muscle acidosis and soreness (the so-called Delayed Onset Muscle Soreness, DOMS) in vertebrates. The aim of the study was to determine the activities/concentrations of compounds involved in the Cori cycle in worker and forager bees. Muscles, fat bodies, and hemolymph from 1- and 14-day-old workers and foragers were collected and assayed for the protein, lactate, glucose, NAD+, and NADH concentrations and lactate dehydrogenase (LDH) activity. Both lactate concentration and LDH activity in the hemolymph, muscles, and fat bodies increased with age. The concentrations of NAD+ and NADH in the tissues decreased with ageing/senescence, whereas protein concentrations increased until day 14 of bee's life and then decreased in foragers. The concentration of glucose decreased in the hemolymph and muscles and increased in the fat bodies. Elevated lactate concentrations in foragers may indicate transition from the aerobic to the anaerobic phase and development of metabolic acidosis that may eventually lead to muscle damage/soreness and shorter lifespan. When analyzing flight dynamics, load mass, and bee behavior, changes in the concentrations of Cori cycle compounds should be taken into account.
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PMID:Comparison of Lactate Dehydrogenase Activity in Hive and Forager Honeybees May Indicate Delayed Onset Muscle Soreness - Preliminary Studies. 3122 35