Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0426980 (motor symptom)
 471 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The short plasma half-life limits the antiparkinsonian efficacy of levodopa/carbidopa (LD/CD). Administration of LD/CD with the catechol-O-methyltransferase inhibitor entacapone in one tablet (LCE) may extend plasma half-life of LD and thus its effect on motor symptoms in patients with Parkinson's disease (PD). The objectives of this study were to monitor the motor response to a switch from LD/CD to LCE by a simultaneous performance of an instrumental motor test and rating of motor symptoms and to compare the LD plasma behavior between both conditions in terms of stability. Twenty-one treated PD patients received LD/CD and then the identical oral LD dosage of LCE within a standardized setting on 2 consecutive days. Rating better reflected the motor improvement after LD application than the instrumental test. Motor symptoms of PD patients decreased significantly more during the LCE than the LD/CD condition, probably due to significantly higher LD plasma levels and a significantly less pronounced fall of the LD concentrations following the second LD intake. Our study shows a more stable LD plasma behavior during LCE intake and accordingly a better effect on motor symptoms according to rating outcomes and motor test results to a lesser extent.
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PMID:Inhibition of catechol-O-methyltransferase contributes to more stable levodopa plasma levels. 1621 93

A matter of debate is the impact of levodopa (LD) application in patients with Parkinson disease (PD) on altered force development and coordination, which are also influenced by the strength of muscles used. The objectives were to compare the motor response, the development of grip strength, and the pharmacokinetic behavior of LD and its main peripheral metabolite 3-O-methyldopa (3-OMD) after intake of 200-mg retarded-release levodopa/carbidopa (LD/CD) and of 150-mg LD/CD/entacapone (LD/CD/EN). Twelve patients with PD received both LD formulations within a standardized setting under double-blind conditions with a crossover design 1 day after the other. Motor symptoms significantly improved, LD plasma concentrations went up, and grip strength increased after both LD/CD and LD/CD/EN administration. There were no significant differences between both conditions with regard to motor response and LD pharmacokinetics. The 3-OMD levels were significantly lower during catechol-O-methyltransferase (COMT) inhibition with entacapone. The LD/CD/EN compound was superior over the retarded-release LD formulation, indicating the impact of LD on grip force. This may be caused by the interference of 3-OMD with the blood-brain barrier transport of LD; therefore, LD delivery is greater during the LD/CD/EN condition. Because the rating scale used does not consider the grip strength, this effect of better blood barrier transport of LD was not reflected. Another hypothesis may be that more acidic metabolites appear during peripheral LD metabolism by means of COMT, whereas COMT inhibition is accompanied by more basic LD metabolites (ie, the tyrosine aminotransferase-dependent substrates dihydroxyphenylpyruvate acetate and trihydroxyphenylacetate). This antiacid scenario may support a better muscle function with a positive impact on muscle excitability and contractibility.
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PMID:Catechol-O-methyltransferase inhibition improves levodopa-associated strength increase in patients with Parkinson disease. 1852 Sep 80