Relationship between thiolactonase activity and hyperhomocysteinemia according to MTHFR gene polymorphism in Tunisian Behçet's disease patients.
BACKGROUND
Behçet's disease (BD) is a multisystemic immuno-inflammatory disorder. Inflammatory processes may cause lipid peroxidation, alteration of lipid profile and increase the risk of atherosclerosis. The aim of this study was to evaluate the association between thiolactonase (HTLase) activity and plasma homocysteine levels (tHcy) in a BD population and to investigate their association with methylenetetrahydrofolate reductase (MTHFR) 677C-->T genotype.


METHODS
A total of 35 BD patients were compared to 39 healthy volunteers.


RESULTS
Significantly higher tHcy levels associated with lower HTLase activities were found in BD patients as compared to healthy controls (p<0.001). These patients also exhibited lower values of triglycerides and high-density lipoprotein cholesterol (HDL-C). Homozygosity for the T allele of the MTHFR gene was more frequent in BD patients (14.3% vs. 7.7%). It was associated with significantly higher tHcy levels (16.9 micromol/L for n=17 vs. 13.1 micromol/L for n=18; p<0.05) and markedly lower HTLase activity (362.6+/-156.7 U/L vs. 414.2+/-180.2 U/L) for the (TT+CT) and CC genotypes, respectively. Moreover, HDL-C levels were inversely correlated with tHcy (r=-0.5; p=0.004) but positively associated with HTLase activity (r=0.374; p=0.038). These correlations were also present in several clinical manifestations, such as ocular, neurological involvement or thrombosis.


CONCLUSIONS
Homozygosity of the T allele of the MTHFR gene is prevalent in BD patients. High levels of tHcy associated with low HTLase activities may be one of the causes leading to thrombosis in BD patients.
Koubaa
Nadia
N
1Laboratory of Biochemistry, UR "Human Nutrition and Metabolic Disorders", Faculty of Medicine, Monastir, Tunisia.
Hammami
Sonia
S
Nakbi
Amel
A
Ben Hamda
Khaldoun
K
Mahjoub
Sylvia
S
Kosaka
Testsuya
T
Hammami
Mohamed
M
D000328:Adult; D001528:Behcet Syndrome / Q000235:genetics*; D002265:Carboxylic Ester Hydrolases / Q000097:blood*; D005260:Female; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D008875:Middle Aged; D011110:Polymorphism, Genetic; D014416:Tunisia
D006710:Homocysteine; D042965:Methylenetetrahydrofolate Reductase (NADPH2); D002265:Carboxylic Ester Hydrolases