Processing grapefruit juice with γ-cyclodextrin attenuates its inhibitory effect on cytochrome P450 3A activity

Area of Science:

• Pharmacology
• Food Science
• Biochemistry

Background:

• Grapefruit juice (Citrus paradisi) is known to inhibit intestinal cytochrome P450 3A4 (CYP3A4), increasing oral drug bioavailability.
• This interaction poses a risk for patients taking medications metabolized by CYP3A4, necessitating avoidance of grapefruit juice.
• Key compounds responsible for this interaction are furanocoumarins like bergamottin (BG) and 6', 7'-dihydroxy bergamottin (DHBG).

Purpose of the Study:

• To investigate if processing grapefruit juice with cyclodextrins (CDs) can prevent or inhibit the drug-grapefruit juice interaction.
• To evaluate the efficacy of different cyclodextrins (α, β, and γCD) in mitigating this interaction.

Main Methods:

• Grapefruit juice and its major furanocoumarins (BG, DHBG) were complexed with α, β, and γCDs.
• The impact of processed samples and furanocoumarins on CYP3A4 activity was compared to unprocessed controls.
• Interactions between CDs and furanocoumarins were studied using phase solubility and 1H NMR.

Main Results:

• Processing grapefruit juice, particularly with γCD, significantly attenuated the inhibition of CYP3A4 activity.
• γCD also demonstrated a similar attenuation effect on the inhibition caused by BG and DHBG.
• Evidence suggests strong encapsulation of BG and DHBG within the γCD cavity.

Conclusions:

• Encapsulation of furanocoumarins (BG, DHBG) by γCD effectively reduces grapefruit juice's inhibitory effect on CYP3A4.
• This cyclodextrin-mediated processing offers a potential strategy for developing grapefruit juice products that avoid drug interactions.