Availability of Guanitoxin in Water Samples Containing Sphaerospermopsis torques-reginae Cells Submitted to Dissolution Tests

Autor(es)

Fernandes, Kelly Afonsina ^[1] ; Ferraz, Humberto Gomes ^[2] ; Vereau, Fanny ^[2] ; Pinto, Ernani ^{[3, 1]}

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Fac Pharmaceut Sci, Dept Clin & Toxicol Anal, Av Prof Lineu Prestes 580, BR-05508900 Butanta, SP - Brazil

^[2] Univ Sao Paulo, Fac Pharmaceut Sci, Dept Pharm, Av Prof Lineu Prestes 580, BR-05508900 Butanta, SP - Brazil

^[3] Univ Sao Paulo, Ctr Nucl Energy Agr, Av Centenario 303, BR-13416000 Piracicaba - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PHARMACEUTICALS; v. 13, n. 11 NOV 2020.
• Citações Web of Science: 0

Resumo

Guanitoxin (GNT) is a potent neurotoxin produced by freshwater cyanobacteria that can cause the deaths of wild and domestic animals. Through reports of animal intoxication by cyanobacteria cells that produce GNT, this study aimed to investigate the bio-accessibility of GNT in simulated solutions of the gastrointestinal content in order to understand the process of toxicosis promoted by GNT in vivo. Dissolution tests were conducted with a mixture of Sphaerospermopsis torques-reginae (Cyanobacteria; Nostocales) cultures (30%) and gastrointestinal solutions with and without proteolytic enzymes (70%) at a temperature of 37 degrees C and rotation at 100 rpm for 2 h. The identification of GNT was performed by LC-QqQ-MS/MS through the transitions {[}M + H](+) m/z 253 > 58 and {[}M + H](+) m/z 253 > 159, which showed high concentrations of GNT in simulated gastric fluid solutions (p-value < 0.001) in comparison to simulated solutions of intestinal content. The gastric solution with pepsin promoted the stability of GNT (p-value < 0.05) compared to the simulated solution of gastric fluid at the same pH without the enzyme. However, the results showed that GNT is also available in intestinal fluids for a period of 2 h, and solutions containing the pancreatin enzyme influenced the bio-accessibility of the toxin more compared to the intestinal medium without enzyme (p-value < 0.05). Therefore, the bio-accessibility of the toxin must be considered both in the stomach and in the intestine, and may help in the diagnosis and prediction of exposure and risk in vivo through the oral ingestion of GNT-producing cyanobacteria cells. (AU)

• Processo FAPESP: 14/50420-9 - Metabólitos secundários produzidos por micro-organismos aquáticos e impacto na qualidade de frutos do mar e de peixes de água doce
• Beneficiário: Ernani Pinto Junior
• Modalidade de apoio: Auxílio à Pesquisa - Regular