GATA Haydarpasa Training Hospital Biochemistry Department ISTANBUL/TURKEY

1. Evaluation of Dihydrofolate Reductase Enzyme Activity and One Carbon Metabolism in Patients with Bipolar Disorder GATA Haydarpasa Training Hospital Biochemistry Department ISTANBUL/TURKEY

2. One Carbon Metabolism THF serine glisine Methylene THF 5-MTHF Methenyl THF Formyl THF

3. One Carbon Metabolism thymidylate synthesis Methionine synthase B12 THF serine METHIONINE SAM glisine Methylene THF SAH HCY 5-MTHF Methenyl THF Formyl THF purine synthesis Methylation reax.

4. One Carbon Metabolism thymidylate synthesis PLASMA n DHF FOLATE DHFR NADPH NADP THF serine METHIONINE SAM glisine Methylene THF SAH HCY 5-MTHF Methenyl THF Formyl THF purine syntesis Methylation reax.

5. One Carbon Metabolism BH2 DHFR BH4 unmetabolized folate PLASMA n DHF FOLATE DHFR NADPH NADP THF serine METHIONINE SAM glisine Methylene THF SAH HCY 5-MTHF Methenyl THF Formyl THF purinsyntesis Methylation reax.

6. One Carbon Metabolism PLASMA n O2 UNCOUPLED DHF FOLATE BH2 DHFR NADPH OXİDATİVE STRESS NADP BH4 THF NO COUPLED serine METHIONINE SAM glisine Methylene THF SAH HCY 5-MTHF Methenyl THF Formyl THF purine syntesis Methylation reax.

7. One Carbon Metabolism PLASMA n DHF FOLATE BH2 tyrozine DHFR NADPH NADP BH4 THF phenylalanine serine METHIONINE SAM glisine Methylene THF SAH HCY 5-MTHF Methenyl THF Formyl THF purine syntesis Methylation reax.

8. One Carbon Metabolism DOPAMINE, SEROTONIN PLASMA n DHF FOLATE BH2 tyrozine DHFR NADPH NADP BH4 THF phenylalanine serine METHIONINE SAM glisine Methylene THF SAH HCY 5-MTHF Methenyl THF Formyl THF purine syntesis Methylation reax.

11. 30 BDP patients 31 healthy controls (with a similar age distribution) Fasting blood and urine • Urine amino acids (GC) • Urine MethylMalonilAcid • (photometric) • DHFR enzyme activty in leukocyte • Plasma Homocysteine (FPIA ) • Serum folate and vit B12(CMIA) • RBC folate (CMIA) • Erytrocyte folic acid subgroup (HPLC-FD) • Serum aminoacid (GC) • Plasma ammonia (Special photometric method prevented interfering factors) DATA Statistical procedures were made by SSPS(Ver 20.0) P value lower than 0.05 was accepted as statistically significant

12. Spectrophotometric DHFR Enzyme Activity Measurement Reagent 1: 100 mMTrisBufferpH: 8.5 2 mM DTT 0.2 M KCl Reagent 2: 60 µM DHF (substrate) Reagent 3: 100mM BicarbonateBuffer 200 µM NADPH Sample V: 100 µL R1: 900 µL R2: 500 µL R3: 100 µL Reactiontype: Kinetic (rate down) MeasurementWavelenght: 340 nm Measurement Time: 30 min

13. RESULTS

14. n PLASMA FOLATE tyrozine DHFR phenylalanine Methenyl THF FOLATE POOL (intracellular) 5-MTHF-Glu4 5-MTHF-Glu6 Formyl THF cystine Transsulfulationreax. LEUKOCYTE anaerobic metabolism alanine DHF Methylation reax. BH2 NADPH NADP BH4 THF serine METHIONINE SAM glisine Methylene THF SAH HCY 5-MTHF

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