Altered Erythrocyte Glycolytic Enzyme Activities in Type-II Diabetes

Area of Science:

• Biochemistry
• Metabolic disorders
• Hematology

Background:

• Glycolysis is a critical metabolic pathway in erythrocytes.
• Type-II diabetes mellitus is associated with significant metabolic alterations.
• Erythrocyte metabolism may be affected by hyperglycemia in diabetes.

Purpose of the Study:

• To investigate the activity of key glycolytic enzymes in erythrocytes of type-II diabetic patients.
• To compare enzyme activities between diabetic and control groups.
• To explore correlations between enzyme activity, blood glucose levels, and diabetes.

Main Methods:

• Erythrocyte lysate was used as the source of glycolytic enzymes.
• Enzyme activities including hexokinase (HK), phosphoglucoisomerase (PGI), phosphofructokinase (PFK), aldolase (ALD), and lactate dehydrogenase (LDH) were measured.
• Activities were compared between type-II diabetic patients and healthy controls.

Main Results:

• Hexokinase (HK) activity increased by 50% in diabetics, while PGI, PFK, and ALD activities decreased significantly (37%, 75%, 64% respectively).
• Despite decreases, PGI, PFK, and ALD activities remained substantially higher than HK activity.
• Lactate dehydrogenase (LDH) activity showed an 85% increase in diabetics.
• Positive correlations with blood sugar were observed for HK, PFK, and ALD in controls, and only PFK in diabetics.

Conclusions:

• Diabetic erythrocytes exhibit altered glycolytic enzyme profiles, with increased HK and LDH but decreased PGI, PFK, and ALD.
• The observed changes suggest that glycolysis in diabetic erythrocytes may be unimpaired or even augmented, potentially due to elevated glucose-6-phosphate (G6P) levels.
• Enzyme activity correlations with blood glucose levels differ between diabetic and control groups, highlighting metabolic adaptations in diabetes.