The effect of coffee supplementation on glutathione and total thiols levels

Abstract

The effect of coffee supplementation on glutathione and total thiols levels Antioxidants are very important substances that counteract the formation of free radicals. They are divided into exogenous, such as vitamin C which the body receives with food, and endogenous. One of the most important endogenous antioxidants is glutathione (-glutamyl-L-cysteinyl-glycine), which plays an important role in cellular defense against oxidative damage. Free glutathione is presented within organisms in both reduced (GSH) and oxidized forms (GSSG). Oxidative stress leads to a decrease in GSH level and therefore a GSH/GSSG ratio that can be used as an indicator of oxidative stress and an indicator of various diseases. The aim of presented study was to develop a sampling method for capillary blood testing, where we have found that this amount (15 µl) is sufficient for our testing. Another aim was to supplement group of volunteers with coffee and to determine GSH levels and levels of total thiols after 0, 48 h and 96 h of supplementation in capillary blood. HPLC with electrochemical detection was used for GSH determination and Ellman's method for determination of total thiols. We could see the GSH slight increase as well as the levels of total thiols.