Glutathione and its redox system in diabetic polymorphonuclear leukocytes

Area of Science:

• Biochemistry
• Immunology
• Diabetology

Background:

• Diabetic complications are often linked to oxidative stress.
• Polymorphonuclear leukocytes (PMNs) play a crucial role in immune response and are susceptible to oxidative damage.
• Glutathione is a key intracellular antioxidant crucial for cellular defense.

Purpose of the Study:

• To investigate the status of the glutathione system in polymorphonuclear leukocytes (PMNs) of diabetic patients.
• To determine the impact of ketosis on the glutathione system in diabetes.
• To assess the effect of insulin therapy on PMN glutathione levels and activity.

Main Methods:

• Quantification of reduced glutathione levels in PMNs.
• Measurement of glutathione reductase and glutathione peroxidase activities in PMNs.
• Comparison between diabetic patients (with and without ketosis) and healthy controls.
• Evaluation of PMNs from insulin-treated diabetic patients.

Main Results:

• Significantly decreased levels of reduced glutathione were observed in diabetic PMNs compared to normal.
• Glutathione peroxidase activity was significantly reduced in diabetic PMNs, while glutathione reductase activity remained unchanged.
• Ketosis did not exacerbate the observed alterations in the glutathione system.
• Insulin treatment led to a significant restoration of glutathione levels and enzyme activities in PMNs.

Conclusions:

• Diabetic polymorphonuclear leukocytes exhibit a compromised glutathione system, characterized by reduced glutathione and impaired glutathione peroxidase activity.
• The observed glutathione system dysfunction in diabetes is potentially reversible with insulin therapy.
• These findings highlight the role of the glutathione system in diabetic immune cell function and suggest therapeutic implications.