Glutathione (GSH)
Fresh milk may be a good source of glutathione, a tripeptide of the sulphur amino acid cysteine, plus glycine and glutamic acid. In the organism glutathione has the role as
an antioxidant. Glutathione can be oxidized forming GSSG (oxidized glutathione), and in this reaction it may remove reactive oxygenspecies (ROS), thereby regulating
the level of ROS in the cells. Glutathione participates in regulation of insulin production in the pancreatic cells, as ROS inhibit expression of the pro insulin gene. Glutathione appears to have different important roles in leukocytes,
as a growth factor, as an anti-apoptotic factor in leukocytes and to regulate the pattern of cytokine secretion. GSH, moreover, is also central for antioxidative
defence in the lungs, which may be very important in connection with lower respiratory infections including influenza .