Antitumor activity of liposomal naphthoquinone esters isolated from Thai medicinal plant: Rhinacanthus nasutus KURZ.

Abstract

We previously observed that rhinacanthins-C, -N and -Q, three main naphthoquinone esters isolated from the roots of Thai medicinal plant; Rhinacanthus nasutus KURZ. (Acanthaceae) induced apoptosis of human cervical carcinoma HeLaS3 cells. Since these rhinacanthins showed limited solubility in aqueous medium, we attempted to entrap them into liposomal membrane: Liposomalization enabled injection of the drugs and the drugs were expected to transfer to lipoproteins in the bloodstream. Liposomal formulations of rhinacanthins-C, -N and -Q showed strong antiproliferative activity against HeLaS3 cells with the IC50 values of 32, 17, 70 microM; 19, 17, 52 microM and 2.7, 2.0 and 5.0 microM for the exposure time of 24, 48, and 72 h, respectively. These liposomes suppressed the tumor growth in Meth-A sarcoma-bearing BALB/c mice at the dose of 5.0 mg/kg/d for 10 d. Among rhinacanthins, liposomal rhinacanthin-N significantly suppressed solid tumor growth. Based on these results, our findings demonstrated that rhinacanthin-N suppressed tumor growth in vivo, and suggested that liposomes are useful for preparing injectable formulation of hydrophobic drugs.

• Authors: Pongpun Siripong, Jantana Yahuafai, Kosuke Shimizu, Kanae Ichikawa, Sei Yonezawa, Tomohiro Asai, Kwanjai Kanokmedakul, Somsak Ruchirawat, Naoto Oku
• Journal: Biological & pharmaceutical bulletin (Biol Pharm Bull) Vol. 29 Issue 11 Pg. 2279-83 (Nov 2006) ISSN: 0918-6158 [Print] Japan
• PMID: 17077529 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents, Phytogenic
• Esters
• Lignans
• Liposomes
• Naphthoquinones
• Plant Extracts
• rhinacanthin-N

Topics

• Acanthaceae (chemistry)
• Animals
• Antineoplastic Agents, Phytogenic (chemistry, isolation & purification, pharmacology)
• Ascites (pathology, prevention & control)
• Cell Line, Tumor
• Cell Proliferation (drug effects)
• Dose-Response Relationship, Drug
• Esters
• HeLa Cells
• Humans
• Lignans (chemistry, isolation & purification, pharmacology)
• Liposomes
• Male
• Mice
• Mice, Inbred BALB C
• Molecular Structure
• Naphthoquinones (chemistry, isolation & purification, pharmacology)
• Neoplasm Transplantation (methods)
• Phytotherapy (methods)
• Plant Extracts (chemistry, pharmacology)
• Plant Roots (chemistry)
• Plants, Medicinal (chemistry)
• Sarcoma, Experimental (pathology, prevention & control)
• Survival Analysis
• Thailand