title: Effect of MTHFR polymorphisms on hyperhomocysteinemia in levodopa-treated Parkinsonian patients.
abstract: High plasma homocysteine levels have been observed in Parkinson's disease (PD) patients treated with levodopa. In this study, we investigated the effects of C677T and A1298C MTHFR polymorphisms, in association with L-DOPA daily dose and vitamin status, on hyperhomocysteinemia development in PD patients. Plasma homocysteine and folate/vitamin B12 levels were assayed in 49 L-DOPA-treated PD patients, and compared with those of 86 healthy subjects. Genotyping for MTHFR polymorphisms was carried out by DG-DGGE. Homocysteine levels were significantly higher in patients than in controls (16.3 +/- 5.7 vs. 11.7 +/- 2.7 micromol/l, P < 0.01). No significant differences were found between patients and controls with regard to folate/vitamin B12 levels, and MTHFR allele distribution. The TT+AA genotype was significantly more frequent in PD patients than in controls (32.5% vs. 17.4%, P < 0.05), but not associated with an increased risk for PD (OR = 2.3, CI = 1.0-5.2). Further, patients carrier of this genotype exhibited a mild hyperhomocysteinemia (22.1 +/- 4.9 micromol/l), while a protective effect was observed in patients having the CC+AA genotype (11.2 +/- 1.6 micromol/l; OR = 0.19, CI = 0.06-0.59). Interestingly, homocysteine levels were also moderately increased in patients with CT heterozygous genotype, in the context of either AA or AC (14.5 +/- 3.6 micromol/l), in comparison to subjects with the CC + AA genotype. Finally, we did not find any significant association of combined C677T and A1298C MTHFR polymorphisms with an increased risk for hyperhomocysteinemia in PD patients. A better understanding of the role of homocysteine and MTHFR genotypes in PD is needed to reveal novel approaches for disease management.
authors.affiliation: Department of Biochemical, Physiological and Nutritional Sciences, University of Messina, Via Consolare Valeria, Policlinico Universitario, Messina, 98125, Italy. dcaccamo@unime.it
authors.forename: D
authors.initials: D
authors.lastname: Caccamo
authors.forename: G
authors.initials: G
authors.lastname: Gorgone
authors.forename: M
authors.initials: M
authors.lastname: Currò
authors.forename: G
authors.initials: G
authors.lastname: Parisi
authors.forename: W
authors.initials: W
authors.lastname: Di Iorio
authors.forename: C
authors.initials: C
authors.lastname: Menichetti
authors.forename: V
authors.initials: V
authors.lastname: Belcastro
authors.forename: L
authors.initials: L
authors.lastname: Parnetti
authors.forename: A
authors.initials: A
authors.lastname: Rossi
authors.forename: F
authors.initials: F
authors.lastname: Pisani
authors.forename: R
authors.initials: R
authors.lastname: Ientile
authors.forename: P
authors.initials: P
authors.lastname: Calabresi
mesh_terms: D000368:Aged; D000978:Antiparkinson Agents / Q000627:therapeutic use*; D005260:Female; D005492:Folic Acid / Q000097:blood; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D020138:Hyperhomocysteinemia / Q000201:enzymology* / Q000235:genetics; D007980:Levodopa / Q000627:therapeutic use*; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics / Q000502:physiology*; D008875:Middle Aged; D010300:Parkinson Disease / Q000188:drug therapy* / Q000201:enzymology / Q000235:genetics; D011110:Polymorphism, Genetic; D014805:Vitamin B 12 / Q000097:blood
chemical_list: D000978:Antiparkinson Agents; D006710:Homocysteine; D007980:Levodopa; D005492:Folic Acid; D042965:Methylenetetrahydrofolate Reductase (NADPH2); D014805:Vitamin B 12