Safety assessment of selected medicinal food plants used in Ayurveda through CYP450 enzyme inhibition study

Abstract

Background: Andrographis paniculata, Bacopa monnieri and Centella asiatica are mentioned in Ayurveda for the management of neurodegenerative disorders. These plants and their phytomolecules, such as andrographolide, bacoside A and asiaticoside, were studied for their inhibition potential on pooled CYP450 as well as human CYP3A4, CYP2D6, CYP2C9 and CYP1A2 by CYP-CO complex assay and fluorogenic assay respectively followed by IC₅₀ determination. Quantification of bioactive compounds present in the extracts was done by RP-HPLC. Heavy metal content in the selected medicinal plants was determined by atomic absorption spectroscopy.

Result: CYP-CO complex assay indicated significantly less inhibition potential than standard inhibitor (P < 0.05 and above). A. paniculata showed highest inhibitory activity against CYP3A4 and CYP2D6 (IC₅₀ = 63.06 ± 1.35 µg mL^-1 ; 88.80 ± 3.32 µg mL^-1 ), whereas C. asiatica and B. monnieri showed least inhibitory activity against CYP1A2 (IC₅₀ = 288.83 ± 1.61 µg mL^-1 ) and CYP2C9 (184.68 ± 3.79 µg mL^-1 ), respectively. In all cases the extract showed higher inhibition than the single bioactive compounds. The heavy metals content in the plant extracts were within the permissible limits.

Conclusion: The findings suggested that selected food plants and bioactive compounds contributed negligible interaction potential with CYP isozymes and may not possess any harmful effect with regard to their therapeutic application. © 2016 Society of Chemical Industry.

Keywords: atomic absorption spectroscopy; cytochrome P450; medicinal food plants; standardisation.