Table 3.

Effect of SY or SeMet on serum PSA and blood glucose and free and bound GSH in healthy men

Change from baseline
GroupBaseline3 mo6 mo9 mo12 mo
Glucose (mg/dL)a
 Placebo84.7 ± 2.291.28 ± 2.013.06 ± 2.323.72 ± 2.764.28 ± 1.79
 SY (200 μg/d)91.6 ± 1.650.12 ± 2.082.69 ± 2.62−1.44 ± 2.75−1.06 ± 2.70
 SY (285 μg/d)82.7 ± 2.450.40 ± 1.89−3.67 ± 2.571.60 ± 5.311.00 ± 3.09
 SeMet (200 μg/d)91.0 ± 2.07−0.50 ± 0.96−1.45 ± 1.03−1.75 ± 2.46−2.20 ± 2.49
PSA (ng/mL)a
 Placebo1.03 ± 0.120.07 ± 0.030.32 ± 0.220.37 ± 0.260.05 ± 0.06
 SY (200 μg/d)1.40 ± 0.290.14 ± 0.090.22 ± 0.130.34 ± 0.300.74 ± 0.50
 SY (285 μg/d)0.59 ± 0.060.05 ± 0.030.09 ± 0.040.08 ± 0.040.06 ± 0.05
 SeMet (200 μg/d)1.14 ± 0.16−0.08 ± 9.090.06 ± 0.070.02 ± 0.080.02 ± 0.07
GSH (μmol/mL)
 Placebo0.94 ± 0.08NDND−0.12 ± 0.08−0.09 ± 0.09
 SY (200 μg/d)0.90 ± 0.07NDND−0.05 ± 0.08−0.01 ± 0.12
 SY (285 μg/d)0.94 ± 0.09NDND−0.02 ± 0.09−0.10 ± 0.07
 SeMet (200 μg/d)0.99 ± 0.07NDND−0.22 ± 0.07b−0.11 ± 0.08
Protein bound GSH (% of total GSH)
 Placebo17.7 ± 1.85NDND−1.37 ± 2.40−1.14 ± 2.31
 SY (200 μg/d)16.5 ± 1.64NDND−0.39 ± 1.970.54 ± 2.43
 SY (285 μg/d)15.7 ± 1.33NDND1.86 ± 2.574.17 ± 2.09
 SeMet (200 μg/d)16.8 ± 1.61NDND1.25 ± 1.79−0.51 ± 2.34

NOTE: Subjects were randomized to placebo (n = 18), 200 μg/d SY (n = 16), 285 μg/d SY (n = 15), or 200 μg/d SeMet (n = 20). Values are mean ± SE.

Abbreviation: ND, not determined.

  • aEligibility criteria: Glucose <106 mg/dL; normal PSA based on age- and race-specific cutoffs (Ref. 15).

  • bStatistically significant from baseline (P < 0.05).