Tag Archives: methionine

Measurement of methionine level with the LC-ESI-MS/MS method in schizophrenic patients

S. Kulaksizoglu1, B. Kulaksizoglu2, H. Y. Ellidag1, E. Eren1, N. Yilmaz1, A. Baykal3

1Central Laboratories of Antalya Education and Research Hospital,
Department of Biochemistry, Antalya, Turkey;
e-mail: sblclngrgl@yahoo.co.uk;
2Antalya Education and Research Hospital, Department of Psychiatry, Antalya, Turkey;
3Akdeniz University School of Medicine, Department of Biochemistry, Antalya, Turkey

The purpose of this study was to evaluate plasma methionine levels by using liquid chromatography electrospray ionization-tandem mass spectroscopy (LC-ESI-MS/MS) in schizophrenic patients. A twelve-point standard graph was drawn, and the recovery rate, the intra-day and inter-day coefficients of variation (CV), the limit of detection (LOD), and the limit of quantification (LOQ) were evaluated. The y and R2 values of the standard graph equation were determined as 0.011x + 0.0179 and 0.9989, respectively, and the graph remained linear until the 200 µmol/l level. The intra-day coefficients of variation of the samples (n = 10) containing 8, 28, and 58 µmol/l methionine were determined as 2.68, 3.10, and 3.79%, respectively; while their inter-day coefficients of variation were determined as 2.98, 3.19, and 3.84%. The LOD and LOQ values were determined as 0.04 and 0.1 µmol/l, respectively, while the mean recovery rates were determined as 101.7 and 99.3%. Plasma methionine values were measured as 21.5 (19.5-24,6) µmol/l for the patient group, 17.8 (16.3-20.1) µmol/l for the control group, and the difference between the two groups was statistically significant (p = 0.03). LC-ESI-MS/MS method represents a fairly sensitive, economic, and rapid analysis that requires very little sample and is suitable for measuring methionine levels in schizophrenic patients.

Mechanism of hepatoprotective action of methionine and composition “Metovitan” against a background of antituberculosis drugs administration to rats

S. I. Anisimova1, G. V. Donchenko2, Yu. M. Parkhomenko2, V. M. Kovalenko1

1SI Institute of Pharmacology and Toxicology, National Academy of Medical Sciences of Ukraine, Kyiv;
2Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: kovalenko_toxy@yahoo.com

Oral administration of antituberculosis drugs to rats for 60 days in doses that are equivalent to clinical ones, causes changes in mRNA levels expression of liver cytochrome P-450 isoforms CYP3A2, CYP2C23, CYP2E1 and pro- and antioxidant state. Experimental composition “Metovitan” given with anti-TB drugs provided a correction of these abnormalities, that is evidenced by modulation of the level of CYP3A2, CYP2C23, CYP2E1 gene expression and antioxidant activity, inhibition of lipid peroxidation. “Metovitan” normalizes the enzymatic activity and content of total billirubin in the blood serum, shows high hepatoprotective properties, exceeding the efficiency of methionine.