Glutathione S-transferase M1 and T1 gene polymorphisms with consumption of high fruit-juice and vegetable diet affect antioxidant capacity in healthy adults.
Study Goal
The researchers aimed to determine whether the antioxidant effects of a high fruit-juice and vegetable diet vary based on GSTM1/GSTT1 genotypes.
Results Summary
The study found that a high fruit-juice and vegetable diet increased antioxidant capacity and enzyme activities, with stronger and faster effects in participants with GSTM1+/GSTT1+ genotypes compared to those with GSTM1-/GSTT1- genotypes.
Population
24 healthy volunteers with different GST genotypes (12 GSTM1+/GSTT1+ and 12 GSTM1-/GSTT1-).
Effective Dosage
Not specified (controlled diet high in fruit-juice and vegetables).
Duration
2 weeks.
Interactions
None mentioned.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
high fruit-juice and vegetable diet | increase | GST activities | GSTM1+/GSTT1+ group | - | increased | #1 |
high fruit-juice and vegetable diet | increase | GR activities | GSTM1+/GSTT1+ group | - | increased | #2 |
high fruit-juice and vegetable diet | no change | GST activities | GSTM1-/GSTT1- participants | - | no effects were observed | #3 |
high fruit-juice and vegetable diet | no change | GR activities | GSTM1-/GSTT1- participants | - | no effects were observed | #4 |
Dietary intervention | increase | total antioxidant capacity | all participants | - | increased | #5 |
Dietary intervention | decrease | plasma malondialdehyde content | all participants | - | decreased | #6 |
high fruit-juice and vegetable diet | increase | total antioxidant capacity and plasma malondialdehyde content | GSTM1+/GSTT1+ participants | - | respond more quickly | #7 |
diet intervention | increase | glutathione peroxidase activities | all participants | - | effective in enhancing | #8 |
diet intervention | increase | catalase activities | all participants | - | effective in enhancing | #9 |
diet intervention | no change | erythrocyte superoxide dismutase activity | all participants | - | no influence | #10 |
OBJECTIVE: To our knowledge, no data have yet shown the combined effects of GSTM1/GSTT1 gene polymorphisms with high consumption of a fruit and vegetable diet on the body's antioxidant capacity. A 2-wk dietary intervention in healthy participants was conducted to test the hypothesis that the antioxidant biomarkers in individuals with different glutathione-S-transferases (GST) genotypes will be different in response to a high fruit-juice and vegetable diet. METHODS: In our study, 24 healthy volunteers with different GST genotypes (12 GSTM1+/GSTT1+ and 12 GSTM1-/GSTT1- participants) consumed a controlled diet high in fruit-juice and vegetables for 2 wk. Blood and first-void urine specimens were obtained at baseline, 1-wk, and 2-wk intervals. The antioxidant capacity-related biomarkers in blood and urine were observed and recorded at the scheduled times. RESULTS: Erythrocyte GST and glutathione reductase (GR) activities response to a high fruit-juice and vegetable diet are GST genotype-dependent. Two weeks on the high fruit-juice and vegetable diet increased GST and GR activities in the GSTM1+/GSTT1+ group (P < 0.05 compared with baseline or GSTM1-/GSTT1- group), although no effects were observed on GST and GR activities in GSTM1-/GSTT1- participants. Dietary intervention increased total antioxidant capacity and decreased plasma malondialdehyde content in all participants (P < 0.05 compared with baseline), whereas GSTM1+/GSTT1+ participants respond more quickly to a high fruit-juice and vegetable diet than GSTM1-/GSTT1- participants. The diet intervention was effective in enhancing glutathione peroxidase and catalase activities in all participants (P < 0.05 compared with baseline), although there was no influence on erythrocyte superoxide dismutase activity (P > 0.05). CONCLUSION: The effects of a diet rich in fruit-juice and vegetables on antioxidant capacity were dependent on GSTM1/GSTT1 genotypes.