Expression of 8-OHdG in Zosterisessor ophiocephalus from the Venetian lagoon, Italy.

The aim of the present work was to evaluate the expression of 8-OHdG (8-hydroxydeoxyguanosine) in the benthic fish Zosterisessor ophiocephalus collected in two differently polluted sites of the Venetian lagoon (Porto Marghera and Caroman). We compared our data on 8-OHdG with those of CYP1A (Cytochrome P450, family 1, subfamily A, polypeptide 1), which is a well known biomarker for detoxification of contaminants. Immunohistochemistry with an antibody to 8-OHdG showed immunopositivity in nuclei of hepatocytes as well as in melanomacrophage centres of spleen and kidney, whereas an anti-CYP1A antibody exhibited positive immunostaining in the liver, kidney and ovary. The liver of males showed higher expression of both proteins than females. In animals from Porto Marghera site, the enzymatic assay for 8-OHdG exhibited higher levels in liver of males than in females. Western Blot analysis using the antibody anti-CYP1A recognized the presence of a band of about 60 kDa in the liver of males and females. Males exhibited a strong band, whereas in females the band showed a lower intensity. By using Real-Time PCR, the mRNA expression of CYP1A did not show any differences between males and females from each site, but it was at borderline significance level. Comparing the two sites, mRNA expression of CYP1A was significantly higher in the liver of both males and females from Porto Marghera than that of Caroman. The present data suggest that pollutants are bio-available as demonstrated by our biomarker analyses and may have a harmful effect on aquatic organisms such as Z. ophiocephalus. We report that the highest levels of hepatic 8-OHdG and CYP1A expression were detected in males, showing clear gender specificity.

Expression of heat shock protein 70 in the liver of extensively and intensively kept heavy pigs.

The objective of this work was to investigate the expression of heat shock protein 70 (HSP70) by Western blot (WB) in swine liver. Subsequently, the study aimed to apply this method to two experimental groups of heavy pigs raised in different confinement systems: intensive/indoor (Group A) and extensive/outdoor (Group B). Thirty-six crossbred commercial heavy pigs were divided as follows: Group A (eight castrated males and eight females) was equally distributed into two single-sex indoor pens (1.02 m²/pig); Group B (11 castrated males and nine females) was kept in one single (partially grassy and partially wooded) open area of about 6000 m². Group A was slaughtered at 41 weeks of age (170 ± 9 kg) and Group B at 48 weeks of age (172 ± 13 kg). At the abattoir the livers of all the animals were collected and analyzed by WB assay in order to quantify the levels of HSP70. Moreover, a further liver sample was taken from the same animals in order to investigate the cellular localization of HSP70 by immunohistochemistry (IHC). The interaction between sex and group resulted statistically significant (P = 0.001). When stratified by sex, Group A showed significantly higher HSP70 values compared with Group B for both male and female subjects (P < 0.001). Stratifying by group, males showed significantly higher HSP70 values than females in Group A (P < 0.001), whereas no statistical differences were observed between sexes for Group B (P = 0.653). The IHC results evidenced cytoplasmic immunoreactivity in a granular pattern in both groups. The different expression pattern observed by WB could prove to be a useful tool in the assessment of pig health and welfare.

Seasonal effects on hematological and innate immune parameters in sea bass Dicentrarchus labrax.

The temperate aquatic environment is affected by two primary components of season, temperature and photoperiod, during the annual cycle. Many organisms respond to seasonal change physiologically, behaviorally or both. The aim of this study was to investigate the effect of seasonality on cortisol, hematological and innate immune parameters in European sea bass reared under traditional semi-intensive aquaculture. Sea bass (Dicentrarchus labrax) were reared in an outdoor pond and serum cortisol, hematocrit, leucocrit, serum lysozyme activity and total glutathione were bimonthly monitored over a 14-months period. The effect of seasonality was observed for all parameters carried out, with generally higher values in summer and lower in winter. These results could improve the understanding of the influence of seasonal cues on the immune system and hematological parameters in fish in order to optimize the husbandry practices.

Immunohistochemical localization of IGF-I, IGF-II and MSTN proteins during development of triploid sea bass (Dicentrarchus labrax).

The cellular localization of IGF-I, IGF-II and MSTN proteins was investigated during ontogenesis of triploid sea bass (Dicentrarchus labrax) by an immunohistochemical approach. The results were compared with those observed in diploids. IGF-I immunostaining was mainly observed in skin, skeletal muscle, intestine and gills of both diploids and triploids. From day 30 of larval life, IGF-I immunoreactivity observed in skeletal muscle, intestine, gills and kidney was stronger in triploids than in diploids. At day 30, triploids exhibited a standard length significantly higher than the one of diploids. Although IGF-II and MSTN immunoreactivity was detectable in different tissues and organs, no differences between diploids and triploids were observed. The spatial localization of IGF-I, IGF-II and MSTN proteins detected in this study is in agreement with previous findings on the distribution of these proteins in diploid larvae and fry. The highest IGF-I immunoreactivity observed in triploids suggests a possible involvement of ploidy in their growth performance.

Immunohistochemical localization of constitutive and inducible heat shock protein 70 in carp (Cyprinus carpio) and trout (Oncorhynchus mykiss) exposed to transport stress.

In the present work we investigated by immunohistochemistry the cellular localization of constitutive as well as inducible heat shock protein 70 in several tissues of common carp (Cyprinus carpio) and rainbow trout (Oncorhynchus mykiss) exposed to transport stress.In carp, the constitutive form (HSC70) was detected only in red skeletal muscle of both control and stressed animals. In the same species, the inducible form (HSP70) was evident in the epithelia of renal tubules,gills and skin of stressed animals, whereas in controls only red skeletal muscle exhibited an immunopositivity to HSP70 antibody. In trout, immunostaining to HSC70 antibody was found mainly in the epithelia of intestine, gills and skin of both control and stressed animals although the reactivity was generally higher in animals exposed to transport stress. In the same species immunostaining to HSP70 antibody was observed only in red skeletal muscle and epidermis of control animals.