Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036474 (scurvy)
 685 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Scurvy-like symptoms have been seen in experimental copper deficiency. This forecasts a role for the vitamin in copper metabolism. Ascorbate has been known to antagonize the intestinal absorption of copper. More recent studies have characterized a postabsorption role for ascorbate in the transfer of copper ions into cells. The vitamin reacts directly or indirectly with ceruloplasmin, a serum copper protein, specifically labilizing the bound copper atoms and facilitating their cross-membrane transport. Ascorbate at physiological levels and above impedes the intracellular binding of copper to Cu,Zn superoxide dismutase. The mechanism is unclear but nonetheless suggests both positive and negative regulatory functions for ascorbate in copper metabolism.
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PMID:A role for ascorbic acid in copper transport. 196 69

Kinky hair disease, first described in 1962, is a sex-linked disorder, with its gene located on the long arm of the X chromosome close to the centromere. The condition is marked by intellectural deterioration, seizures, and poorly pigmented, friable hair. Bony changes, resembling scurvy, tortuosities of the cerebral and systemic vasculature, and diverticuli of the bladder are also seen. Biochemically, the most diagnostic alteration is a marked reduction in blood copper and ceruloplasmin levels. The mechanism for the low serum copper has not been defined. Even though parental copper administration will correct the biochemical abnormalities, such treatment will not arrest cerebral deterioration.
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PMID:Kinky hair disease: twenty five years later. 283 49

Female, adult guinea pigs were fed a low ascorbic acid diet ad libitum. Oral administrations of either estinyl (5 micrograms) or progestogen (250 micrograms) in combination with 5 mg of ascorbic acid (minimum requirement) daily for 21 d, resulted in significantly lower (P less than 0.05) concentrations of ascorbic acid in plasma, liver, adrenals and urine than in animals receiving only 5 mg of the vitamin. None of these animals showed any clinical signs of ascorbic acid deficiency. Clinical manifestations of scurvy were exhibited, however, when animals receiving no ascorbic acid supplement were treated with the steroid hormones for 7 d. All of these animals died by d 10. On the other hand, the animals receiving neither ascorbic acid nor the steroids remained free from any signs of scurvy, except one (out of six), which died by d 12. In vitro studies revealed a markedly higher rate of oxidation of ascorbic acid in the presence of either estinyl or progestogen than in untreated controls. These results were further supported by a higher level of plasma ceruloplasmin in animals receiving a combination of estrogen and progestogen than in animals receiving no hormones. An in vivo dose-related effect of ascorbic acid indicated that the steroid-mediated lowering effect of the vitamin status could be counteracted by increasing the dose of ascorbic acid from 5 to 10 mg/d for 2 wk. These results suggest that the interactions between oral contraceptive hormones and ascorbic acid may be of clinical importance only in the case of borderline intake of the vitamin.
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PMID:Effects of estrogen and progestogen on the ascorbic acid status of female guinea pigs. 395 5

Serum and liver ceruloplasmin levels rose markedly in guinea pigs with acute scurvy and with chronic latent scurvy. Their increase in the former condition can be attributed to the general stress reaction, but the increase in ceruloplasmin levels in concentration may have a stimulant effect on the ceruloplasmin, when the oxidation of Fe2+ to Fe3+ is potentiated, may obstruct the binding of iron to protoporphyrin and prevent formation of the haeme of cytochrome P 450 and b5.
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PMID:Acute and chronic vitamin C deficiency in guinea-pigs: its effect on ceruloplasmin and cytochrome P 450 and b5 levels. 621 11