Oral Glutathione Supplementation on the Levels of Blood Glutathione

Penn State Health

Status: Completed

Conditions: Healthy Adults

Treatments: Drug: Glutathione supplementation; Drug: Gluthathione peroxidases; Other: Placebo

Study type: Interventional

Funder types: Other

Identifiers

NCT01044277

PSHCI 09-059

Details and patient eligibility

About

This trial is designed to provide evidence of the efficacy of glutathione supplementation and health(GSH) and includes the assessment of both short term and long term effects. Based on previous laboratory animal studies and clinical data, the investigators anticipate that the effects of oral GSH supplementation will be progressive and cumulative. The study will also allow for the evaluation of effects of withdrawal of the supplement on the outcome variables.

Full description

This is a randomized double-blind, placebo-controlled study in which the treatment allocations will be kept sealed until the final statistical evaluation. The design will include the recruitment of 60 healthy subjects (30-79 yr of age) randomized into 3 groups. A total of 48 subjects, 16 per group will be required based upon power calculations and results from a previous clinical trial with selenium. An additional 4 subjects per group will be placed on trial to account for possible attrition or non-compliance. Blood, urine and exfoliated buccal mucosal samples will be obtained from all subjects at baseline. Questionnaire data on usual dietary intake will also be obtained at baseline. Eligible subjects will be required to have not have taken any high dose antioxidant supplements for at least 1 month prior to the study. Subjects will then begin supplementation according to the following schedule:

Group A, GSH (500 mg, 2 times daily); Group B, GSH (125 mg, 2 times daily); Group C, placebo (2 times daily). Eligible participants who sign the informed consent will be randomly assigned to either placebo or high or low dose Glutathione groups. Participants will be asked not to consume any other high-dose vitamin, multi-vitamin, or mineral supplements containing glutathione throughout the study in order to prevent variation in dose of supplemental GSH between subjects. Supplementation will continue for 6 months with biological samples collected at 1, 3 and 6 months after baseline. At 6 months, supplementation will be discontinued. A final collection of biological samples will occur 1 month afterwards. Compliance will be monitored by pill count.

Levels of glutathione will be measured in plasma, lymphocytes, and red blood cells as well as in exfoliated buccal mucosal cells. Biomarkers of oxidative stress will include blood levels of glutathionylated proteins and 8-isoprostanes and urine levels of 8-hydroxydeoxyguanosine. Glutamylcystine ligase and GST activities, and C-reactive protein will be determined in blood. Immune function biomarkers will be analyzed including t-natural killer cell cytotoxicity, lymphoproliferation, neutrophils phagocytosis, neutrophil respiratory burst assays.

Enrollment: 61 patients

Sex: All

Ages: 30 to 79 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Healthy male and females between the ages of 30 and 79 years of age
• Not taking glutathione as a dietary supplement
• Not taking high dose antioxidant supplement prior to 1 month
• Baseline blood glutathione level of < 1 mmol/L

Exclusion criteria

• History or evidence of disease including cancer, diabetes, heart disease
• Subjects who smoke

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

---

61 participants in 3 patient groups, including a placebo group

Group A

Experimental group

Description:

Glutathione supplementation-Double-Blind - GSH 500 mg/GSH 125 mg/Placebo Other name Gluthathione peroxidases

Treatment:

Drug: Glutathione supplementation

Group B

Experimental group

Description:

Glutathione supplementation-Double-Blind - GSH 500 mg/GSH 125 mg/Placebo Other name Gluthathione peroxidases

Treatment:

Drug: Gluthathione peroxidases

Group C

Placebo Comparator group

Description:

Placebo-Double-Blind - GSH 500 mg/GSH 125 mg/Placebo

Treatment:

Other: Placebo