Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:1.3.5.1 (succinate dehydrogenase)
8,177 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Certain aspects of lipid metabolism have been examined in denervated muscle from normal mice and in dystrophic muscle from mice of the Bar Harbor strain 129. A number of parameters show no change or similar changes. For example, the utilization of palmitate-[1-14C] and palmitylcarnitine by mitochondria from denervated and dystrophic hind leg skeletal muscle showed parallel decreased in the oxidation of palmitate (30-42%) and palmitylcarnite (37-66%). A comparable study with acetylcarnitine showed a striking difference with no change evident in mitochondria from denervated muscle and 80-85% decrease in dystrophic muscle. The study of succinate dehydrogenase and the enzymes of beta-oxidation in the above mitochondrial preparation showed similar findings except for acyl CoA dehydrogenase activity (an enzyme with a regulatory role in beta-oxidation) which was significantly diminished (29%) in denervated muscle, whereas no change was observed in dystrophic muscle. The findings show a close parallel in a number of parameters but distinct differences were observed in denervated as compared with dystrophic muscle. It is unlikely that the muscular disorder in murine muscular dystrophy can be explained solely on the basis of denervation or the loss of a neural trophic factor.
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PMID:Comparison of the intermediary metabolism of fatty acids in denervated and dystrophic murine skeletal muscle. 17 5

A sporadic case of central core disease in a 5 1/2-year-old girl is reported. Clinically, a retarded motor development existed, furthermore, a muscle weakness and hypotonia of the extremities and trunk, contractures of the hip- and knee-joint,and luxation of both hip-joints. Biopsy specimens are taken from both Mm. gastrocnemii. Muscle fibres show, by morphologic examination, 95 per cent cores, which are characteristic for this myopathy. A further abnormality is seen inthe histochemical preparations for phosphorylase, succinate dehydrogenase, NAD diaphorase tetrazolium reductase, myofibrillar ATPase as well as AS-reaction with and without diastase digestion. With these techniques the muscle fibres show an uniform reaction pattern in which the activities of the oxidative andglycolytic enzymes correspond to the type I fibres of healthy persons. The cores show a lack of a activity of the oxidative and glycolytic enzymes as well as are ATPase- and PAS-negative. By reason of this histochemical behaviour it is suggested that the cores are predominantly unstructured. The cause of this disease might be complex disturbances in the neuro-muscular system manifested in the fetal period.
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PMID:[A case of central core disease. Light microscopic and histochemical studies (author's transl)]. 84 74

Histochemical investigation of 32 biopsy specimens of the muscular tissue taken in patients with Erb's myopathy and 15 bioptic materials from patients with Charcot--Marie--Tooth's amyotrophy was carried out. Characteristics of distribution of enzymes (succinate dehydrogenase, lactate dehydrogenase) in the muscular tissue of the patients referred to above are presented. A quantitative evaluation of the activity of enzymes was made by the method of count of granules of diphormazan with subsequent treatment of data by the statistical variation method.
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PMID:[Changes in the activity of succinate dehydrogenase and lactate dehydrogenase in the muscles of patients with progressive muscular dystrophy]. 92 61

Patients with a hereditary mitochondrial myopathy with succinate dehydrogenase (SDH) deficiency and abnormal lactacidosis during physical exercise have a low work capacity when exercising for about 10-15 min. Their maximum voluntary muscular strength is fairly normal. The relationship between the time (t) and a constant workload (N) that a healthy subject can maximally sustain can be expressed as: log t = beta + alpha log N. For normal subjects the constant alpha is approximately -5 and the constant beta has a large interindividual variation. Of four myopathy patients alpha was determined from two or three maximum bicycle exercise tests of different duration (including ramp- and steady-state tests using a new application of the method of adding submaximal loads to the final maximum workload). The value of alpha varied between -1.0 and -1.81 and beta had low values, both significantly different from those of healthy subjects. The alpha values explain the divergent results that may be obtained with different types of exercise tests in some of these patients, i.e. a normal or moderately reduced capacity in exercise tests of short duration (for example a short Tornvall or a ramp type of test) and a very low exercise capacity in tests of longer duration (for example a steady state type of test with workloads chosen to allow at least two loads). The low absolute value of alpha may be related to the abnormally increased anaerobic metabolism of these patients during exercise, caused by the SDH deficiency.
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PMID:Dependence of maximum performance time on work intensity in patients with a hereditary myopathy with succinate dehydrogenase deficiency. 139 48

The effects of up to 4 months dietary supplementation with 40% galactose on muscle and nerve function were examined in rats. Galactitol, a polyol pathway metabolite, accumulated to high levels in both tissues. This led to changes similar to those found in experimental diabetes, which were largely prevented by treatment with an inhibitor of the first enzyme in the pathway, aldose reductase. For fast twitch extensor digitorum longus muscle there was weight loss, fibre damage, slowing of twitch time to peak, increased twitch tension, and reduced tetanic tension. There were no relaxation deficits. For slow twitch soleus there were no changes in tension production. However, contraction and relaxation for both twitch and tetanus were prolonged. Fatigue resistance was reduced after 1 week. Damage in soleus led to a reduction in mean fibre area after 2 months, which largely recovered by 4 months. There was a selective loss of fast oxidative glycolytic fibres. Histochemical staining for succinic dehydrogenase was normal in galactosaemic soleus, in contrast to the marked reduction seen in diabetes. Sciatic nerve conduction velocity was reduced after 2 months, particularly in normally fast conducting motor and sensory fibres. Resistance to hypoxic conduction block was increased in galactosaemic nerves to diabetic levels. It was concluded that polyol pathway hyperactivity is likely to contribute to the aetiology of diabetic myopathy and neuropathy, and that experimental galactosaemia provides a good model in which to study pathway effects without the complicated hormonal changes found in diabetes.
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PMID:Muscle and nerve dysfunction in rats with experimental galactosaemia. 153 21

A histochemical study of cytochrome c oxidase (CCO) was performed in the muscles from eight patients with full-blown zidovudine myopathy. All patients had ragged-red fibres (total cumulative count: 160) and myofilamentous changes, that predominated in type 1 fibres and included diffuse or punch-out myofibrillar loss (75 affected fibres) and constant cytoplasmic body formation (106 affected fibres). Inflammatory infiltrates were present in four out of eight patients. A partial CCO deficiency (22-47% of fibres; both types 1 and 2 affected) was detected in all cases, and contrasted with the normal or increased succinate dehydrogenase activity observed in most fibres. Among CCO-deficient fibres, 71% were normal on trichrome, but all ragged-red fibres were CCO-negative. Myofilamentous changes were restricted to CCO-deficient fibres. The present study strongly supports the idea that mitochondrial toxicity is the specific mechanism of zidovudine myopathy.
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PMID:Partial cytochrome c oxidase deficiency and cytoplasmic bodies in patients with zidovudine myopathy. 166 20

An unusual hereditary myopathy with paroxysmal myoglobinuria has been described previously. We have studied muscle biopsy specimens taken before and after exercise to exhaustion (24 min at 20-25 W) in a young woman with this condition. Marked glycogenolysis with lactate production and marked phosphagen breakdown (ATP + CP) were observed after exercise, and almost all type I fibres were found to be depleted of glycogen. Succinate dehydrogenase (SDH) activity was low, while the activities of 3-OH-acyl-CoA-dehydrogenase, phosphofructokinase, phosphorylase and lactate dehydrogenase were normal. On electron microscopy, the mitochondria showed abnormalities typical of mitochondrial myopathy. The findings in our patient suggest a limitation of mitochondrial function, probably related to SDH in the tricarboxylic acid cycle and complex II in the electron transport chain. This may explain the inability of ATP regeneration to keep pace with ATP utilization during exercise. Other metabolic defects may coexist.
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PMID:Low succinate dehydrogenase (SDH) activity in a patient with a hereditary myopathy with paroxysmal myoglobinuria. 238 36

Corticosteroids have been shown to produce a myopathy of peripheral skeletal muscle, characterized predominantly by Type II fiber atrophy. To determine if similar histologic and histochemical changes occur in the diaphragm and whether the in vitro contractile properties of this muscle are adversely affected by steroids, we studied two groups of hamsters. The experimental group received triamcinolone while a control group received saline, both given daily for 3 wk as i.m. injections. Soleus (Sol) and extensor digitorum longus (EDL) muscles and costal diaphragm muscle sections were stained for histologic (hematoxylin and eosin, modified Gomori trichrome) and histochemical (myosin ATPase, succinate dehydrogenase [SDH]) analysis. Muscle fiber proportions and cross-sectional areas (CSA) were measured from myosin ATPase sections. In vitro studies of isometric contractions were carried out on small strips of costal diaphragm, measuring maximal isometric twitch (Pt) and tetanus (Po) tensions, time to peak tension (TTP), half relaxation time (1/2 RT), force-frequency relationship, and fatigue characteristics (60 Hz tetani; duty cycle, 0.5). Triamcinolone treatment resulted in no change in muscle fiber proportions. There was no effect on Type I fiber CSA; however, there was Type IIa (Sol, EDL) and Type IIb (diaphragm, EDL) fiber atrophy in triamcinolone-treated animals. Pt and Po (normalized for weight) of diaphragm strips were not different. There was a prolongation in TTP and 1/2 RT, a left shift in the force-frequency curve, and a reduced fatiguability of triamcinolone-treated diaphragm (P less than 0.05). We conclude that a steroid myopathy could be explained by a loss of muscle mass (Type IIb fiber atrophy) rather than an intrinsic impairment in contractile function.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Pathologic changes and contractile properties of the diaphragm in corticosteroid myopathy in hamsters: comparison to peripheral muscle. 262 59

Single-fiber analyses using a kinetic microphotometric method were performed on three patients with chronic progressive external ophthalmoplegia and proximal myopathy accompanied by a partial deficiency of cytochrome c oxidase. Two patients had subsarcolemmal accumulation of mitochondria (ragged-red fibers). Qualitative histochemical demonstration of cytochrome c oxidase showed a mosaic of fibers without detectable cytochrome c oxidase activity. Quantitative single fiber measurements in the patients' biopsies showed that the majority of the muscle fibers had decreased cytochrome c oxidase activity without selective involvement of a specific fiber type. Succinate dehydrogenase was measured and the ratio of the activities (succinate dehydrogenase/cytochrome c oxidase) was calculated. Normal muscle showed a ratio of about 2, whereas diseased muscle showed values between 10 and 20, due to a decrease in cytochrome c oxidase activity. Ragged-red fibers showed very low or undetectable cytochrome c oxidase activity.
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PMID:Enzyme activity measured in single muscle fibers in partial cytochrome c oxidase deficiency. 282 55

We have studied a 17-year-old girl with lactic acidosis (3-18 mEq/liter) and progressive muscle weakness since 9 years of age. Morphological findings in muscle were of a typical ragged red myopathy with multiple collections of bizarre mitochondria, some containing paracrystalline inclusions. The carnitine content of serum and muscle was normal, as were the activities of carnitine palmitoyltransferase, carnitine octanoyltransferase, and carnitine acetyltransferase in the patient's muscle. Measurement of the enzymes of oxidative phosphorylation in both crude muscle homogenates and mitochondrial fractions showed close to normal activities of cytochrome c oxidase, succinate dehydrogenase, and ATPase. In contrast, succinate cytochrome c reductase activity was greatly reduced in the patient, being 0.035 mumol/min/g tissue in whole muscle (controls 1.16 +/- 0.47 mumol/min/g tissue) and 8 nmol/min/mg protein in the mitochondria (control, 340 nmol/min/mg protein). Rotenonesensitive NADH-cytochrome c reductase was also undetectable in the patient's mitochondria. Spectral analysis of cytochromes showed decrease of reducible cytochrome b to 16% of the control. These results indicate a defect of ubiquinol-cytochrome c reductase or the cytochrome bc1 segment (complex III) of the electron transport chain. Antibody-binding studies of the individual components of complex III showed additional deficiencies of core proteins I and II and peptide VI, indicating a more widespread defect of complex III than was evident from spectral analysis and enzyme activity measurements alone. Urine organic acid analysis after fasting and following a medium chain triglyceride load showed unusually high levels of lactate and 3-hydroxybutyrate, lower than expected levels of acetoacetate and dicarboxylic acids, and the presence of several other metabolites suggesting a disturbed citric acid cycle and redox state.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Lactic acidosis and mitochondrial myopathy associated with deficiency of several components of complex III of the respiratory chain. 609 35


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