Rapid effects of 17β-estradiol on cell signaling and function of Mytilus hemocytes

Bisphenol-A alters gene expression and functional parameters in molluscan hepatopancreas

“…Increased NL accumulation in bivalve tissues indicates either increased synthesis or decreased utilisation of neutral lipids, as well as impairment of lysosomal lipases, leading to enhanced autophagy of the accumulated lipids in digestive cells often associated to lysosomal membrane destabilization (Moore et al, 2006). Overall, the results further support the hypothesis that the lysosomal system represents a significant target for estrogenic compounds in molluscan cells (Moore et al, 1978;Canesi et al, 2004aCanesi et al, ,b, 2006Canesi et al, , 2007 like in mammalian cells (Szego et al, 1975). In bivalves, the hepatopancreas plays a central role in metabolism through intracellular digestion of food particles and in distribution of nutrients to reproductive tissues during gamete maturation (Dimitriadis et al, 2004).…”

“…In vitro, the effects of BPA were prevented or significantly reduced by the antiestrogen Tamoxifen, suggesting the involvement of ERs (Canesi et al, 2004b). Although BPA, like E 2, activated ERK MAPKs, both in vitro and in vivo, the xenoestrogen induced dephosphorylation of p38 MAPK and of transcription factors (such as STAT5 and CREB) (Canesi et al, 2004b(Canesi et al, , 2005Porte et al, 2006) that are activated 17 by E 2 (Canesi et al, 2004a. Moreover, the in vivo effects were observed at concentrations of BPA comparable to those of E 2 and to environmental exposure levels (Canesi et al, 2005).…”

“…In Mytilus immunocytes, BPA rapidly affected the lysosomal function both in vitro (Canesi et al, 2004b) and in vivo (Canesi et al, 2005); these effects were mediated by interference with components of rapid kinase-mediated cell signalling that are activated by E 2 (Canesi et al, 2004a;Porte et al, 2006). In this work, the possible effects of BPA on gene expression and functional parameters of mussel hepatopancreas were investigated and the results compared with those obtained with E 2 in the same experimental conditions (Canesi et al, 2007).…”

“…Molluscan ERs, although phylogenetically clustered with other steroid receptors, 4 appear to be functionally different: their transcriptional activity is constitutive, and not activated by estrogens (Thornton et al, 2003;Keay et al, 2006). However, in ganglia and immune cells of the bivalve Mytilus, 17β-estradiol (E 2 ) has been shown to act through rapid, 'alternative' modes of action through modulation of Ca 2+ -and kinase-mediated cascades (Stefano et al, 2003;Canesi et al, 2004a. Moreover, we have recently demonstrated that in Mytilus hepatopancreas (or digestive gland), a tissue that plays a central role in metabolism, E 2 modulates different functional parameters and increases the expression of antioxidant genes (Canesi et al, 2007).…”

The Effects of 4-Nonylphenol on the Immune Response of The Pacific Oyster, Crassostrea Gigas, Following Bacterial Infection (Vibrio Campbellii)

“…Currently, there is some data documenting the effects of 4-NP on the immune systems of bivalves; however, there is a lack of research studying immune responses in the economically important Pacific oyster. To date, 4-NP has been shown to decrease immune functions in mussels (Canesi et al, 2004(Canesi et al, , 2007, cockles (Matozzo et al, 2008), and clams (Matozza and Marin, 2005). Exposure to other xenobiotics (e.g., heavy metals and organotoxins) has been shown to decrease phagocytosis (Auffert et al, 2002) and impair cell-to-cell aggregations (Auffret and Obella, 1997) in oyster hemocytes.…”