Glucose-6-phosphate Dehydrogenase Deficiency: The Good, Bad and the Ugly

My childhood friend, Tolu had been living with anemia for the past three years, I had thought. His endurance on the football field was always low and he could not walk as far as the most of us. Just yesterday, Tolu told me he had never been diagnosed of anemia. I was quite shocked. Minutes later, I decided to do a Google search on some of his deficiencies and then I found out Tolu had Glucose-6-Phosphate Dehydrogenase Deficiency.

What Is Glucose-6-phosphate Dehydrogenase Deficiency?

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Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a genetic disorder or condition causing red blood cells to break down. G6PD is responsible for keeping red blood cells healthy so they can function properly and live a normal life span. It is the deficiency of the enzyme, glucose-6-phosphate dehydrogenase, which is the most prevalent enzyme in humans. Glucose-6-phosphate is an enzyme which converts glucose-6-phosphate to 6-phosphogluconate, leading to the production of a very potent antioxidant called Nicotinamide Adenine Dinucleotide Phosphate (NADPH). A deficiency of glucose-6-phosphate dehydrogenase will thus cause a reduced pool of NADPH in the body leading to oxidative stress which is a serious health risk in the body causing anemia, partial blindness and in extreme cases cancer. Anyway, there is something patients with G6PD deficiency have to enjoy.

Glucose-6-phosphate Dehydrogenase Deficiency: The Good

Most diseases will only cause damage to body cells, tissues and organs. But for G6PD deficient individuals, there is something to enjoy. Resistance to malaria! The malaria parasite, Plasmodium falciparum, does not thrive well in the presence of oxidative stress. In G6PD deficient patients, the plasma levels of NADPH is reduced. Since, NADPH is reduced, the body cannot scavenge oxygen radicals and hence the level of oxygen radicals in the body is increased. Oxygen radicals are very harmful to the body. They cause the oxidation of membranes. The malaria parasite, plasmodium falciparum, is very sensitive to oxidative stress and is destroyed by a level of oxidative stress which is tolerable to a G6PD deficient individual. By this mechanism, G6PD deficient individuals enjoy a malaria free life and by natural selection, they survive in areas where malaria infection is rampant.

Glucose-6-phosphate Dehydrogenase Deficiency: The Bad

G6PD deficiency might offer resistance to malaria. But the high level of oxidative stress caused by this condition still makes it a bad omen. Two main health risks which result from G6PD deficiency are hemolytic anemia and partial blindness. Free oxygen radicals in the blood oxidise cell membranes of erythrocytes (red blood cells) and cause its breakdown, releasing its contents into the blood and reducing its concentration in the blood. This condition is called hemolytic anemia. It is so called because the decrease in the red blood cell count is due to hemolysis. Hemolytic anemia is characterized by recurring episodes of moderate to extreme hypoxia, low hemoglobin concentration, fatigue, jaundice and blackening of urine. Apart from causing breakdown of red blood cells, the oxygen radicals due to G6PD deficiency also oxidise lens proteins, rendering the lens less elastic. This is the cause of the partial blindness in G6PD deficient individuals.

Glucose-6-phosphate Dehydrogenase Deficiency: The Ugly

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The ugly face of glucose-6-phosphate dehydrogenase deficiency is cancer. G6PD deficiency when not properly managed can on the long run, cause cancer. The mechanism behind this is that the oxygen radicals which can no longer be removed by the body due to low NADPH levels cause damage to DNA segments. This damage can cause mutation to occur in the DNA which can trigger spontaneous replication. This spontaneous replication is what leads to cancer.

Conclusion

Now that I am more enlightened about his deficiency, I know what Tolu wants and needs at every time. I also took it upon myself to always watch him.

References

Healthline
Emedicine
Medlineplus

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