Transcriptional and biochemical effects of cadmium and manganese on the defense system of octopus vulgaris paralarvae

Abstract

Due to anthropogenic activities the relative concentrations of cadmium andmanganese have increased in the marine environment. Cephalopods are able to accumulate such metals and, as inhabitant of coastal waters, Octopus vulgaris is continuously exposed to anthropogenic activities. Since no study is available on the effects of heavy metals at molecular level in developing octopuses, hereinwe exposed 1-day-old paralarvae for 24 h to 10, 100, and 1000 μ g/L of CdCl2 orMnCl2. Cd exerted a concentration-dependent inhibition of survival and a reduction in growth ratewas shownwhileMn exposure did not affect the survival rate even at the highest concentrations. Gene expression profiles of hsp70, sod, cat, and gst genes were analyzed by quantitative real-time PCR and defined patterns of transcription were observed.Moreover posttranscriptional analyses were also performed suggesting the impairment of metabolic functions, under strong oxidative conditions (as occurred in paralarvae exposed to Cd) or the complete detoxification events (as occurred in paralarvae exposed to Mn).