Beneficial effect of S-adenosyl-l-methionine in lead intoxication. Another approach to clinical therapy

Abstract 1. 1. Five patients with chronic lead intoxication were treated with S-adenosyl- l -methionine (12 mg/kg body weight, daily), given intravenously, over a period of 22 days. 2. 2. A significant recovery of erythrocytic ALA-D was observed in all cases, after therapy. 3. 3. Blood lead content significantly pathologic at the beginning of SAM administration, rapidly decreased within 24–48 h of initiating treatment, reaching nearly control values at the end of the trial. 4. 4. A good correlation between recovery of ALA-D activity and decreased concentration of lead in RBC was found. 5. 5. GSH content in blood was diminished in lead poisoned patients, increasing to normal levels after SAM administration. 6. 6. Other biochemical parameters such as Deaminase activity in RBC, ALA, PBG, porphyrins and lead in urine and serum γ-GT were measured, showing no important deviations from control values before, during or after treatment. 7. 7. Both biochemical and clinical improvement was observed, indicating that SAM therapy is beneficial in the treatment of lead intoxication. No untoward signs were observed. 8. 8. The mechanism of action of SAM is not yet clear; however, a chelating effect could be excluded, and very likely its action can be attributed to glutathione availability.