In-vitro hepatotoxic activity of mitragynine and paynantheine isolated from the leaves of Mitragyna speciosa Korth. (Kratom)

Abstract

Mitragynine, a primary alkaloid found in kratom leaves has been reported to have a broad range of pharmacological and toxicological properties while its congener, paynatheine has comparatively less information available on these aspects. Mitragynine and its congener, paynantheine, were isolated from the ethanol kratom leaves extract using gravity column chromatography techniques. Our study evaluated the cytotoxicity potential of mitragynine and paynantheine on normal human liver cell line, HL-7702, and human hepatoma cell line, HepG2. Mitragynine exhibited a moderate inhibitory effect on the HepG2 cell line with IC₅₀ value of 42.11 ± 1.31 μM in comparison with vinblastine (IC₅₀: 15.45 ± 0.72 μM) while it showed non-cytotoxic properties towards the HL-7702 cell line with concentrations ranging below 200 μM. In contrast, paynantheine exhibited weak cytotoxic properties towards HepG2 and HL-7702 cell lines. Further comprehensive evaluations of both compounds are needed to establish more details on the cytotoxicity potential of kratom alkaloids.

Graphical Abstract

Keywords:

• Mitragynine
• paynantheine
• kratom alkaloids
• cytotoxicity
• hepatoxicity

Disclosure statement

The authors declare that they have no conflict of interest.

Additional information

Funding

The authors would like to thank the Malaysian Ministry of Higher Education and Centre for Drug Research, Universiti Sains Malaysia (USM) for providing research facilities and financial support through the HICoE programme (311/CDADAH/4401009).