RESUMO
The study examined the radioprotective activity of an aqueous extract from Pleurotus ostreatus mycelium administered to Balb/c mice. Male mice were whole-body irradiated on day 0 ((60)Co, at 0.43 Gy/min) and divided into two groups. The extract was administered intraperitoneally to one group (100 mg/kg) on days - 10 to - 6 and - 2 to +1 with respect to the irradiation. The irradiated-control group was injected with saline solution; non-irradiated mice were used as negative controls. The radioprotective effect was evident by increases in bone marrow cellularity (5.1 × 10(6)/femur vs. 1.1 × 10(6)/femur in saline-control mice, p < 0.05), leucocyte counts (10.5 × 10(9)/L vs. 4.5 × 10(9)/L, p < 0.05), and spleen cellularity (11.2 × 10(7)/spleen vs. 6.2 × 10(7)/spleen, p < 0.05). The extract stimulated macrophage phagocytic activity as judged by a faster rate of carbon clearance in terms of absorbance ratios (1.62 vs. 2.01, p < 0.05). Therefore, this extract may be a candidate therapeutic agent with radioprotective activity for haematopoiesis damage, particularly to cells involved in immune function.
Assuntos
Hematopoese/efeitos dos fármacos , Pleurotus/química , Protetores contra Radiação/química , Agaricales/química , Animais , Medula Óssea/efeitos dos fármacos , Medula Óssea/efeitos da radiação , Contagem de Leucócitos , Macrófagos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos BALB C , Micélio/química , Fagocitose , Baço/efeitos dos fármacos , Baço/efeitos da radiaçãoRESUMO
Micronucleus (MN) and other nuclear abnormalities have been measured in the hemocytes of mussels Perna perna to verify whether feeding mussels with different concentrations of Prorocentrum lima results in accumulation of levels of okadaic acid (OA) capable of inducing genotoxic effects at the chromosome level, as evidenced by micronuclei and nuclear abnormalities. Four groups of 12 mussels housed individually in aquaria containing filtered seawater were fed with different concentrations of P. lima. Another group collected directly from the production area served as outdoor control. A significantly higher frequency of MN and nuclear lesions was observed in hemocytes from the groups fed P. lima.
Assuntos
Bivalves/genética , Dinoflagellida/química , Testes para Micronúcleos , Testes de Mutagenicidade , Animais , Cromatografia Líquida de Alta Pressão , Cromossomos/efeitos dos fármacos , Cromossomos/genética , Hemócitos/efeitos dos fármacos , Hemócitos/ultraestrutura , Toxinas Marinhas/toxicidade , Ácido Okadáico/metabolismoRESUMO
Some toxins present in the marine environment are capable of inducing mutagenicity and/or carcinogenicity. Among these toxins, okadaic acid (OA) is gaining considerable interest since it induces DNA based modifications at low concentrations and accumulates in filter-feeding marine animals, including those used for human consumption. This study aims to evaluate the genotoxicity of OA in the haemocytes of the mussel Perna perna, using the micronucleus assay. Fifty-four mussels were separated into three groups of 18 animals. One group received 0.3 microg of OA diluted in 10 microl of ethanol and ultrapure water while the other groups were considered as controls and were exposed to a solvent plus seawater mixture. A significantly higher frequency of micronuclei was observed in haemocytes from the OA-exposed group. There were no statistical differences between the two control groups.