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
Query: EC:1.3.5.1 (
succinate dehydrogenase
)
8,177
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
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.
...
PMID:Muscle and nerve dysfunction in rats with experimental galactosaemia. 153 21
A single oral dose of di-n-butyl phthalate (DBP) to male rats caused histologically a sloughing of the germ cells at 6 h. On Days 1 and 2 more severe sloughing was seen, followed by atrophy and the dissociation of the germ cells from the Sertoli cells and the spermatogonia. Biochemically, there was elevation of gamma-glutamyl transferase, a decrease in sorbitol levels at 3 h and a decrease in the activity of
aldose reductase
at 6 h, in the testes of treated rats. This was followed by decreases in fructose levels and increases in the activity of lactate dehydrogenase (LDH) and in lactate levels at 12 h, and decreases in the activities of sorbitol dehydrogenase and
succinate dehydrogenase
on Day 2. LDH isoenzymes 4 and 5 increased at 6 h prior to the increase in lactate levels. Increases in the levels of inositol and the activities of alkaline phosphatase and lactate dehydrogenase were also observed. Thus, these data suggest that DBP-induced testicular toxicity is caused by a shortage of energy fuels from glucose metabolism or by an anoxia.
...
PMID:Mechanism of testicular atrophy induced by di-n-butyl phthalate in rats. Part 2. The effects on some testicular enzymes. 239 8
This study examined the effect of inhibition of
aldose reductase
, the first enzyme in the polyol pathway, on fast and slow twitch skeletal muscle morphology and function in streptozotocin-induced diabetes in rats. There was a preventative investigation with diabetes duration of 4 months, and a reversal investigation where treatment was given for 2 months following an untreated period of 2 months. For slow twitch soleus muscle, contractions were prolonged by diabetes, and this was partially prevented but not reversed by treatment. Relaxation was profoundly slowed, and both prevention and reversal ameliorated the changes. Diabetes had minimal effects on tension production for soleus. However, for fast twitch extensor digitorum longus, although there was little effect on speed-related contractile parameters, tetanic tension production was progressively reduced with diabetes duration. This effect was antagonized by treatment. Soleus fatigue resistance was markedly reduced by diabetes, but restored to normal by treatment. There was a reduction in oxidative enzyme staining (
succinic dehydrogenase
), and capillary-fibre ratio, both of which were ameliorated by
aldose reductase
inhibition. Mean soleus fibre area was reduced after 4 months of diabetes, and this was prevented but not reversed by treatment. Fibre area was also reduced in extensor digitorum longus, particularly for fast glycolytic fibres. There was a small amelioration with treatment. It is concluded that enhanced polyol pathway activity makes a contribution to diabetic myopathy, and that
aldose reductase
inhibitors can prevent this by actions on muscle fibres and their vascular supply.
...
PMID:Polyol pathway-related skeletal muscle contractile and morphological abnormalities in diabetic rats. 847 Dec 37
Diabetic hyperglycaemia causes a variety of pathological changes in small vessels, arteries and peripheral nerves. Vascular endothelial cells are an important target of hyperglycaemic damage, but the mechanisms underlying this damage are not fully understood. Three seemingly independent biochemical pathways are involved in the pathogenesis: glucose-induced activation of protein kinase C isoforms; increased formation of glucose-derived advanced glycation end-products; and increased glucose flux through the
aldose reductase
pathway. The relevance of each of these pathways is supported by animal studies in which pathway-specific inhibitors prevent various hyperglycaemia-induced abnormalities. Hyperglycaemia increases the production of reactive oxygen species inside cultured bovine aortic endothelial cells. Here we show that this increase in reactive oxygen species is prevented by an inhibitor of electron transport chain
complex II
, by an uncoupler of oxidative phosphorylation, by uncoupling protein-1 and by manganese superoxide dismutase. Normalizing levels of mitochondrial reactive oxygen species with each of these agents prevents glucose-induced activation of protein kinase C, formation of advanced glycation end-products, sorbitol accumulation and NFkappaB activation.
...
PMID:Normalizing mitochondrial superoxide production blocks three pathways of hyperglycaemic damage. 1078 95