From the Guidelines
Glutathione is a powerful antioxidant composed of three amino acids: glutamine, glycine, and cysteine, playing crucial roles in immune function, detoxification, and cellular health. It works by neutralizing harmful free radicals and reactive oxygen species that can damage cells, while also helping to regenerate other antioxidants like vitamins C and E. The body's glutathione levels naturally decrease with age, illness, and exposure to toxins. According to the most recent and highest quality study, 1, glutathione is essential for maintaining redox potential and calcium homeostasis, and its levels are affected by the availability of cysteine, a major substrate for glutathione synthesis.
Some key points to consider:
- Glutathione deficiency has been linked to various health conditions, including liver disease, immune disorders, and neurodegenerative diseases, as noted in 1.
- While glutathione supplements exist in various forms, their effectiveness varies significantly, with oral glutathione having limited absorption in the digestive system, and IV administration providing better bioavailability but requiring medical supervision, as discussed in 1.
- Some people take precursor supplements like N-acetylcysteine (NAC) at doses of 600-1800mg daily to support natural glutathione production, as mentioned in 1.
- The use of glutamine, a component of glutathione, has been shown to have beneficial effects in certain patient populations, such as those with major burns or trauma, as noted in 1.
Overall, maintaining adequate glutathione levels is crucial for overall health and well-being, and further research is needed to fully understand its therapeutic potential, as highlighted in 1.
From the Research
Definition and Function of Glutathione
- Glutathione (GSH) is a cysteine-containing tripeptide with reducing and nucleophilic properties that plays a crucial role in cellular protection from oxidative damage of lipids, proteins, and nucleic acids 2.
- It regulates the metabolism of proteins and their activities by means of thiol-disulfide exchange and plays a key role in protection and detoxification as a cofactor of glutathione peroxidases and glutathione-S-transferases 2.
- GSH is a major intracellular antioxidant capable of scavenging free radicals and detoxifying electrophiles from endogenous and exogenous sources via the free thiol group 3.
Role in Cellular Processes
- GSH is involved in a multiple cellular process, including cell differentiation, proliferation, and apoptosis 3.
- It is a key determinant of redox signaling, vital in detoxification of xenobiotics, and regulates cell proliferation, apoptosis, immune function, and fibrogenesis 4.
- GSH plays an important role in protecting against cellular damage, tissue degeneration, and disease progression in various models 5.
Synthesis and Regulation
- The biosynthesis of GSH occurs in the cytosol in a tightly regulated manner, with key determinants being the availability of the sulfur amino acid precursor, cysteine, and the activity of the rate-limiting enzyme, glutamate cysteine ligase (GCL) 4.
- GSH synthesis is regulated at multiple levels, including transcriptional regulation by key transcription factors such as NF-E2 related factor 2 (Nrf2) via the antioxidant response element (ARE), AP-1, and nuclear factor kappa B (NFκB) 4.
- Dietary glycine can be rate-limiting for glutathione synthesis in normally fed humans, and supplemental glycine may promote glutathione synthesis 6.