[Effects of intervention therapy of methylcobalamin and folic acid on plasma homocysteine concentration and homocysteine thiolactonases/paraoxonase activity in patients with type 2 diabetes mellitus].
OBJECTIVE
To study the effects of methylcobalamin and folic acid treatment on plasma homocysteine (Hcy) level and homocysteine thiolactonase/paraoxonase (HTase/PON) activity in patients with type 2 diabetes mellitus.


METHODS
120 patients with type 2 diabetes mellitus were randomly divided into four equal groups: Group I, receiving no intervention therapy as control group, Group II, given folic acid orally (5 mg/d), Group III, receiving intramuscular injection of methylcobalamin (500 microg qd), and Group IV, treated with methylcobalamin (500 microg qd) in addition to folic acid (5 mg/d). Forty healthy age-matched persons were used as normal controls. Before and 12 weeks after 2-week treatment, plasma total Hcy, vitamin B(12), folic acid, and HTase/PON activity were assayed.


RESULTS
After 12-week treatment the plasma folic acid and methylcobalamin, and Hcy levels decreased and serum HTase/PON activity increased significantly in the three groups receiving intervention treatment (all P < 0.05). The Hcy level decreased by 2.8% in Group I, 14.0% in Group II, 37.3% in Group III, and 21.7% in Group IV respectively (all P < 0.01). The HTase/PON activity increased by 2.7% in Group I, 8.0% in Group II, 3.4% in Group III, and 17.6% in Group IV respectively (all P < 0.05).


CONCLUSIONS
Methylcobalamin and folic acid treatment alone can decrease the Hcy level and increase the HTase/PON activity in the patients with type 2 diabetes mellitus, and the methylcobalamin and folic acid combination therapy is much more effective. Folic acid may affect the HTase/PON activity through its antioxidant ability.
Gu
Wei-jun
WJ
Department of Endocrinology, General Hospital of Chinese People's Liberation Army, Beijing 100853, China.
Lu
Ju-ming
JM
Yang
Guo-qing
GQ
Guo
Qing-hua
QH
Dou
Jing-tao
JT
Mu
Yi-ming
YM
Pan
Chang-yu
CY
D000284:Administration, Oral; D000328:Adult; D000368:Aged; D043303:Aryldialkylphosphatase / Q000097:blood / Q000378:metabolism; D002265:Carboxylic Ester Hydrolases / Q000097:blood* / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy*; D004359:Drug Therapy, Combination; D005492:Folic Acid / Q000008:administration & dosage / Q000097:blood / Q000627:therapeutic use*; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D007273:Injections, Intramuscular; D008875:Middle Aged; D016896:Treatment Outcome; D014805:Vitamin B 12 / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000627:therapeutic use; D014803:Vitamin B Complex / Q000008:administration & dosage / Q000627:therapeutic use
D006710:Homocysteine; D014803:Vitamin B Complex; D005492:Folic Acid; C019476:mecobalamin; D002265:Carboxylic Ester Hydrolases; C502233:homocysteine-thiolactonase, human; D043303:Aryldialkylphosphatase; D014805:Vitamin B 12