25 by: Salman Achchige Renudhi Vidathya Kobawaka.

Student – Salman Achchige Renudhi Vidathya Kobawaka.

Enzyme – Cytochrome P450 oxidase (CYP2D6)

EC Number: 1.14.14.1

The Cytochrome P450 oxidase  enzyme is primarily found in the liver in the human body, which is its main site of activity for drug metabolism. However, it is also present in other tissues, such as the small intestine and brain, though in smaller amounts. In the liver, CYP2D6 is located in the endoplasmic reticulum of cells, where it plays a crucial role in the metabolism of various drugs, including codeine and antidepressants.

The CYP2D6 enzyme is a key member of the cytochrome P450 family involved in the metabolism of many medications and substances. It primarily functions to convert drugs into either their active or inactive forms. For example, it metabolizes codeine into morphine, the active pain-relieving compound. CYP2D6 is responsible for processing about 20-25% of commonly prescribed drugs, including antidepressants, antipsychotics, beta-blockers, and opioids. The activity of this enzyme can vary significantly between individuals, influencing drug effectiveness and potential side effects.

Cytochrome P450 oxidase’s activity varies significantly between individuals due to genetic differences, affecting how people respond to medications. This variability makes CYP2D6 crucial for personalized medicine, helping tailor drug dosages for better outcomes. It also plays a role in drug interactions, where inhibitors or inducers can affect drug levels in the body. Given its importance in processing psychiatric medications, understanding CYP2D6 activity is key in mental health treatment.

References

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(5)Meunier, B.; de Visser, S. P.; Shaik, S. Mechanism of Oxidation Reactions Catalyzed by Cytochrome P450 Enzymes. Chemical Reviews 2004, 104 (9), 3947–3980. https://doi.org/10.1021/cr020443g  ‌(Accessed 13th oct).

(6)Wikipedia Contributors. Cytochrome P450. Wikipedia. https://en.wikipedia.org/wiki/Cytochrome_P450  (Accessed 9th oct).