Gamma-Glutamyltransferase: A Predictive Biomarker of Cellular Antioxidant Inadequacy and Disease Risk

Abstract

Gamma-glutamyltransferase (GGT) is a well-established serum marker for alcohol-related liver disease. However, GGT's predictive utility applies well beyond liver disease: elevated GGT is linked to increased risk to a multitude of diseases and conditions, including cardiovascular disease, diabetes, metabolic syndrome (MetS), and all-cause mortality. The literature from multiple population groups worldwide consistently shows strong predictive power for GGT, even across different gender and ethnic categories. Here, we examine the relationship of GGT to other serum markers such as serum ferritin (SF) levels, and we suggest a link to exposure to environmental and endogenous toxins, resulting in oxidative and nitrosative stress. We observe a general upward trend in population levels of GGT over time, particularly in the US and Korea. Since the late 1970s, both GGT and incident MetS and its related disorders have risen in virtual lockstep. GGT is an early predictive marker for atherosclerosis, heart failure, arterial stiffness and plaque, gestational diabetes, and various liver diseases, including viral hepatitis, other infectious diseases, and several life-threatening cancers. We review literature both from the medical sciences and from life insurance industries demonstrating that serum GGT is a superior marker for future disease risk, when compared against multiple other known mortality risk factors.

Supplementation With 2:1 Ratio of N-6:n-3 Polyunsaturated Fatty Acid Improves Liver Steatosis and Serum Cytokine Levels in Young Obese Balinese Women: A Randomized Clinical Trial

“…The release of GGT typically increases oxidative stress [39]; however, serum GGT levels were relatively decreased in this study, indicating that oxidative stress was reduced. Furthermore, GGT has been strongly associated with body lipids, particularly visceral fat, which contribute to the progression of NAFLD [23,24,40].…”

Gamma-glutamyl transferase and cardiovascular disease

“…The association of GGT with other morbid conditions is not covered. For detailed information, the reader may refer to recent reviews on these topics (8,17,18).…”

“…GGT is closely associated with established cardiovascular risk factors (which tend to cluster in patients with higher GGT level), metabolic syndrome and insulin resistance (18). Elevated GGT may be a marker of antioxidant inadequacy and of increased oxidative stress (17). Circulating GGT levels are also closely correlated with the markers of inflammation and thus its elevated activity may signify a heightened inflammatory state (80).…”

Can glyphosate’s disruption of the gut microbiome and induction of sulfate deficiency explain the epidemic in gout and associated diseases in the industrialized world?

“…GGT is an enzyme that decomposes glutathione into its component amino acids (glycine, glutamate and cysteine) and it has been identified as a predictive biomarker of cellular antioxidant inadequacy, as well as both disease and mortality risks [146]. It has also been proposed as a marker for exposure to various environmental pollutants [147].…”