Fructose-derived glycation and immune function: Effects on antigen binding in human IgG and lymphocytes

Diabetes Mellitus (DM), one of the oldest known metabolic disorders, dates back to 3000 BC and continues to have a profound impact on health and the economy. Nutrition plays a critical role in managing diabetes and enhancing overall quality of life. It is also vital for immune system function, as well as in the prevention and treatment of aging-related diseases. A key factor contributing to the global rise in obesity is the excessive consumption of fructose/glucose (corn) syrup, which leads to various metabolic complications. Uncontrolled intake of carbohydrates, particularly sugars like fructose, triggers the Maillard Reaction, a chemical process that occurs between sugars and proteins, resulting in advanced glycation end-products (AGEs). This process is accelerated in diabetic patients due to hyperglycemia, leading to increased glycation of plasma proteins such as immunoglobulins, which play an essential role in the immune system. Studies show that individuals with Diabetes Mellitus experience a higher susceptibility to infections due to increased viral entry, impaired immune responses, reduced viral clearance, and dysregulated inflammatory cytokine production. In this study, human IgG proteins were glycated in vitro using fructose, simulating the damaging effects seen in diabetic conditions. A mixture containing antioxidants like glutathione, oleuropein, and selenium was prepared and incubated with the glycated IgG to assess its protective properties. Lymphocyte cells from healthy volunteers were also treated with fructose and subjected to similar experiments. Results demonstrated that fructose significantly compromises immune function by damaging key proteins, but the antioxidant mixture effectively mitigates this damage, offering a protective mechanism against glycation in the immune system.