title: pH-dependent cytotoxic effects of extracts of the marine sponge Polymastia janeirensis on cancer cell lines.
abstract: The purpose of this work was to study the cytotoxic effects of marine sponge Polymastia janeirensis, which has been observed in the field to release an orange substance that is toxic to fish. The result showed that aqueous extract (pH 7.0) was highly cytotoxic to glioma (U87) and neuroblastoma (SHSY5Y) cancer cell lines (IC50< 1.0 μg/mL). In addition, this extract showed potent antioxidant and procoagulant (decreased the clotting time by 1.7-fold) activities. Interestingly, the cytotoxic effects were pH-dependent since the viability of the cancer cells was not affected with the extract (pH 5.5). The close similarity between the aqueous extract (pH 7.0) and the orange liquid that is released by the sponge indicates that this potential chemical defence of P. janeirensis deserves further investigation.
authors: a Pharmacognosy Laboratory, Faculty of Pharmacy , Federal University of Rio Grande do Sul (UFRGS) , Porto Alegre , Brazil.
authors: Renata
authors: R
authors: Biegelmeyer
authors: b Biochemistry Department, Study Center of Oxidative Stress , Federal University of Rio Grande do Sul (UFRGS) , Porto Alegre , Brazil.
authors: Rafael
authors: R
authors: Schröder
authors: a Pharmacognosy Laboratory, Faculty of Pharmacy , Federal University of Rio Grande do Sul (UFRGS) , Porto Alegre , Brazil.
authors: Douglas F
authors: DF
authors: Rambo
authors: a Pharmacognosy Laboratory, Faculty of Pharmacy , Federal University of Rio Grande do Sul (UFRGS) , Porto Alegre , Brazil.
authors: Roger R
authors: RR
authors: Dresch
authors: c Department of Invertebrates, National Museum , Federal University of Rio de Janeiro (UFRJ) , Rio de Janeiro , Brazil.
authors: João L F
authors: JLF
authors: Carraro
authors: d Zoobotanical Foundation , Museum of Natural Sciences , Porto Alegre , Brazil.
authors: Beatriz
authors: B
authors: Mothes B
authors: b Biochemistry Department, Study Center of Oxidative Stress , Federal University of Rio Grande do Sul (UFRGS) , Porto Alegre , Brazil.
authors: José Cláudio F
authors: JCF
authors: Moreira
authors: b Biochemistry Department, Study Center of Oxidative Stress , Federal University of Rio Grande do Sul (UFRGS) , Porto Alegre , Brazil.
authors: Mario L C
authors: MLC
authors: da Frota Junior
authors: a Pharmacognosy Laboratory, Faculty of Pharmacy , Federal University of Rio Grande do Sul (UFRGS) , Porto Alegre , Brazil.
authors: Amélia T
authors: AT
authors: Henriques
keywords: chemical defence; cytotoxic; pH-dependent activity