Carpobrotus edulis methanol extract inhibits the MDR efflux pumps, enhances killing of phagocytosed S. aureus and promotes immune modulation.
Although alkaloids from the family Aizoaceae have anticancer activity, species of this family have received little attention. Because these alkaloids also exhibit properties normally associated with compounds that have activity at the level of the plasma membrane, a methanol extract of Carpobrotus edulis, a common plant found along the Portuguese coast, was studied for properties normally associated with plasma membrane active compounds. The results of this study show that the extract is non-toxic at concentrations that inhibit a verapamil sensitive efflux pump of L5178 mouse T cell lymphoma cell line thereby rendering these multi-drug resistant cells susceptible to anticancer drugs. These non-toxic concentrations also prime THP-1 human monocyte-derived macrophages to kill ingested Staphylococcus aureus and to promote the release of lymphokines associated with cellular immune functions. The extract also induces the proliferation of THP-1 cells within 1 day of exposure to quantities normally associated with phytohaemagglutinin. The potential role of the compound(s) isolated from this plant in cancer biology is intriguing and is currently under investigation. It is supposed that the resistance modifier and immunomodulatory effect of this plant extract can be exploited in the experimental chemotherapy of cancer and bacterial or viral infections.
Unit of Mycobacteriology, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, Rua da Junqueira 96, 1349-008 Lisboa, Portugal.
Diane
D
Ordway
Judit
J
Hohmann
Miguel
M
Viveiros
Antonio
A
Viveiros
Joseph
J
Molnar
Clara
C
Leandro
Maria Jorge
MJ
Arroz
Maria Amelia
MA
Gracio
Leonard
L
Amaral
D035722:Aizoaceae; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D016525:Antigenic Modulation / Q000187:drug effects; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D018432:Drug Resistance, Multiple; D006801:Humans; D008264:Macrophages / Q000187:drug effects; D051379:Mice; D010936:Plant Extracts / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects*; D014407:Tumor Cells, Cultured / Q000187:drug effects
D000900:Anti-Bacterial Agents; D000972:Antineoplastic Agents, Phytogenic; D010936:Plant Extracts