Oral Glutathione Supplementation on the Levels of Blood Glutathione

Effect of Oral Glutathione Supplementation on the Levels of Blood Glutathione and Markers of Oxidative Stress in Healthy Adults (Glutathione Supplementation and Health (GSH) Study)

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.

Study Overview

• Status: Completed
• Conditions: Healthy Adults
• Intervention / Treatment: Drug: Glutathione supplementation; Drug: Gluthathione peroxidases; Other: Placebo

Detailed 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.

• Study Type: Interventional
• Enrollment (Actual): 61
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Pennsylvania
    • Hershey, Pennsylvania, United States, 17033
      • Penn State Milton S. Hershey Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 30 years to 79 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Group A; Glutathione supplementation-Double-Blind - GSH 500 mg/GSH 125 mg/Placebo Other name Gluthathione peroxidases	Drug: Glutathione supplementation; 500 mg, two times daily; Other Names: Gluthathione Peroxidates; GSH
Experimental: Group B; Glutathione supplementation-Double-Blind - GSH 500 mg/GSH 125 mg/Placebo Other name Gluthathione peroxidases	Drug: Gluthathione peroxidases; 125 mg, two times daily; Other Names: GSH; Glutathione supplementation
Placebo Comparator: Group C; Placebo-Double-Blind - GSH 500 mg/GSH 125 mg/Placebo	Other: Placebo; 2 times daily; Other Names: GSH; Gluthathione peroxidases

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Evaluation of the effect of glutathione on key biomarkers	Blood glutathione status	6 to 7 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Evaluations will be carried out to expand the above comparison by including adjustments for potential prognostic factors.	Biomarkers of oxidative stress and immune function	6 to 7 months

Collaborators and Investigators

• Sponsor: Milton S. Hershey Medical Center
• Investigators: Principal Investigator: John P. Richie, Ph.D., Milton S. Hershey Medical Center

Publications and helpful links

General Publications

• Richie JP Jr, Nichenametla S, Neidig W, Calcagnotto A, Haley JS, Schell TD, Muscat JE. Randomized controlled trial of oral glutathione supplementation on body stores of glutathione. Eur J Nutr. 2015 Mar;54(2):251-63. doi: 10.1007/s00394-014-0706-z. Epub 2014 May 5.

Study record dates

Study Major Dates

• Study Start: February 1, 2010
• Primary Completion (Actual): September 1, 2011
• Study Completion (Actual): October 1, 2014

Study Registration Dates

• First Submitted: January 6, 2010
• First Submitted That Met QC Criteria: January 6, 2010
• First Posted (Estimate): January 7, 2010

Study Record Updates

• Last Update Posted (Actual): September 6, 2022
• Last Update Submitted That Met QC Criteria: August 31, 2022
• Last Verified: August 1, 2022

More Information

Terms related to this study

• Keywords: glutathione; GSH; gluthathione peroxidases
• Other Study ID Numbers: PSHCI 09-059

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Undecided
• IPD Plan Description: At this time we have no plan for sharing, however, if the need should arise, then sharing may be a possibility.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No