Sex-specific biochemical and histological differences in gonads of sea urchins (Psammechinus miliaris) and their response to phenanthrene exposure

Abstract

a b s t r a c tFemale and male individuals of the same species often differ with respect to their susceptibility to toxicant stress. In the present study, sea urchins (Psammechinus miliaris) of both sexes were exposed to high (150 mg L À1 ) and environmentally relevant (5 mg L À1 ) concentrations of phenanthrene over 10 days. While food intake was significantly decreased following exposure to 150 mg L À1 phenanthrene, histological indices (lipofuscin accumulation, fibrosis, oocyte atresia), energetic status (energy charge, sum adenylates, AMP/ATP ratio) as well as ascorbate levels in the gonads showed either little or no effect upon phenanthrene exposure. However, most parameters (vitamin C, energy charge, sum adenylates, AMP/ATP ratio, ATP and ADP concentrations, lipofuscin content, fibrosis) significantly differed between male and female animals. This study illustrates the difficulties to identify toxic injury in reproductive tissue as it may be superimposed by gametogenesis and spawning of gametes.

Lipofuscin-Like Pigment in Gonads of Sea Urchin Strongylocentrotus intermedius as a Potential Biomarker of Marine Pollution: A Field Study

“…1 and 2. Thus, these results, along with data reported previously (Schäfer et al 2011), suggest that decreased antioxidant capacity might be responsible for the greater incidence of LLP in S. intermedius gonads. Some discrepancy in the results of the present study and the study conducted by Schäfer et al (2011) may be related to the different responses of gonads of sea urchins exposed to phenanthrene alone under experimental conditions and those experiencing long-term effects of complex pollution in the field.…”

“…Sea urchin exposure to lower concentrations of phenantrene, e.g., 5 and 150 lg/l, for 10 days also did not cause lipofuscin accumulation in gonads (Schäfer et al 2011). Based on these results and the observation that lipofuscin level depends on gonadal state, the investigators concluded that lipopigment accumulation could not be recognized as an appropriate indicator for pollutant-induced stress in sea urchin gonads.…”

“…In addition, no sex differences were found for both indices. In the study of sea urchin P. miliaris exposed to phenanthrene (5 and 150 lg/l for 10 days), lipofuscin accumulation, quantified as areal density (%) in cross-sections of gonadal tissue, was significantly greater in testes than in ovaries (Schäfer et al 2011). In addition, vitamin C level in the testes was 5 times lower than in the ovaries.…”

Maternal antioxidant provisioning mitigates pollutant-induced oxidative damage in embryos of the temperate sea urchin Evechinus chloroticus

“…These data are interesting since E . chloroticus eggs have high lipid contents and most PAHs are lipophilic 35 . Nevertheless, even low PAH levels are likely to be problematic in eggs as they could be released slowly while the reserves are mobilised during early embryonic development.…”

An ultrastructural study of testes permeability in sea urchins, Strongylocentrotus intermedius

“…Third, nutritive phagocytes themselves can be damaged by toxic molecules, and this damage may have a deleterious effect on cell junctions that connect the nutritive phagocytes and, hence, on junctions' permeability. The experimental studies of toxic effects of cadmium (Lipina et al, 1987;Au et al, 2001), phenanthrene (Schäfer and Köhler, 2009;Schäfer et al, 2010), and phenol (Au et al, 2003) on gametogenesis in sea urchins showed that these toxicants simultaneously affect developing germ cells and nutritive phagocytes. Similar results were reported for sea urchins inhabiting polluted environments, where both germ cells and nutritive phagocytes were affected by pollutants (Vaschenko et al, 2001a,b).…”