Croton oligandrus Pierre & Hutch (Euphorbiaceae) Extracts and Isolated Compounds Reverse HIV-1 Latency

Area of Science:

• Phytochemistry
• Virology
• Immunology

Background:

• *Croton oligandrus* is a tropical tree used in traditional medicine.
• Other *Croton* species have demonstrated HIV latency-reversal properties.
• This study investigated *C. oligandrus* for similar anti-HIV potential.

Purpose of the Study:

• To identify extracts and compounds from *C. oligandrus* with HIV-1 latency-reversing activity.
• To evaluate the efficacy of these agents in J-Lat T cell lines.
• To elucidate the mechanisms of action involved in latency reversal.

Main Methods:

• Stem bark extraction using dichloromethane.
• In vitro testing on J-Lat T cells.
• Flow cytometry to measure GFP expression as a marker for HIV latency reversal.

Main Results:

• Four extracts demonstrated HIV latency reversal, with the most active showing 69.7% reversal at 1 µg/mL.
• Activity exceeded that of prostratin and *Croton megalobotrys* extract.
• Mechanisms involved pathways beyond protein kinase C (PKC) activation and histone deacetylase (HDAC) inhibition.

Conclusions:

• *C. oligandrus* extracts and compounds effectively reverse HIV latency in vitro.
• Novel mechanisms of action, including synergy with romidepsin, were observed.
• These findings suggest potential for *C. oligandrus* in developing adjunct therapies for HIV cure.