title: Pharmacokinetics and distribution of [35S]methylsulfonylmethane following oral administration to rats.
abstract: Methylsulfonylmethane (MSM) is a sulfur-containing compound found in a wide range of human foods including fruits, vegetables, grains, and beverages. More recently, it has been marketed as a dietary supplement worldwide. The objective of this study was to evaluate the pharmacokinetic profile and distribution of radiolabeled MSM in rats. Male Sprague-Dawley rats were administered a single oral dose of [35S]MSM (500 mg/kg), and blood levels of radioactivity were determined at different time points for up to 48 h. Tissue levels of radioactivity at 48 and 120 h and urine and fecal radioactivity levels were measured at different time points for up to 120 h following [35S]MSM administration to rats. Oral [35S]MSM was rapidly and efficiently absorbed with a mean tmax of 2.1 h, Cmax of 622 microg equiv/mL, and AUC0-inf of 15124 h.microg equiv/mL. The t1/2 was 12.2 h. Soft tissue distribution of radioactivity indicated a fairly homogeneous distribution throughout the body with relatively lower concentrations in skin and bone. Approximately 85.8% of the dose was recovered in the urine after 120 h, whereas only 3% was found in the feces. No quantifiable levels of radioactivity were found in any tissues after 120 h, indicating complete elimination of [35S]MSM. The results of this study suggest that [35S]MSM is rapidly absorbed, well distributed, and completely excreted from the body.
authors.affiliation: Burdock Group, 888 17th Street N.W., Suite 810, Washington, D.C. 20006, USA. bmagnuso@umd.edu
authors.forename: Bernadene A
authors.initials: BA
authors.lastname: Magnuson
authors.forename: Jeremy
authors.initials: J
authors.lastname: Appleton
authors.forename: Gregory B
authors.initials: GB
authors.lastname: Ames
mesh_terms: D000818:Animals; D019587:Dietary Supplements; D004121:Dimethyl Sulfoxide / Q000008:administration & dosage* / Q000032:analysis / Q000493:pharmacokinetics*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013450:Sulfones / Q000008:administration & dosage* / Q000032:analysis / Q000493:pharmacokinetics*; D013462:Sulfur Radioisotopes; D014018:Tissue Distribution
chemical_list: D013450:Sulfones; D013462:Sulfur Radioisotopes; C025910:dimethyl sulfone; D004121:Dimethyl Sulfoxide