Another in vitro study has proposed osteopontin as a suitable biomarker for dioxin exposure (Wejheden et al., 2006). It has been suggested by in vitro and in vivo studies that the effects of some dioxin-like compounds on bone tissue could be due to direct interaction with the aryl hydrocarbon receptor (AhR) in osteoblasts and osteoclasts (Naruse et al., 1999 Naruse et al., 2004). However, only few studies have investigated the effect of endocrine disrupting pollutants on bone tissues (Lind et al., 1999 Naruse et al., 1999 Naruse et al., 2004 Tsukamoto et al., 2004 Tsai et al., 2004 Wejheden et al., 2006). Disruption of these mechanisms has been shown to induce severe embryonic skeletal deformities, ectopic calcifications, skeletal fractures, ossification disorders (e.g. In some aspects, skeleton/bone tissue acts as an endocrine tissue that regulates mineral homeostasis (Quarles, 2008), and hormones, in particular estrogens, have long been proven to regulate bone growth and mineralization by direct effect on osteoblast, osteocyte and chondrocyte function (Krum and Brown, 2008). Therefore, experimental data on these pollutants and monitoring tools are needed. skeletal deformities, ectopic calcifications, reduced bone mineral density), few studies have investigated the mechanisms of action of aquatic pollutants in bone and no cellular bioassays are available to determine their bone toxicity. estrogens and aryl hydrocarbon receptors) although subsequent mechanisms of action of endocrine disrupters remain largely unknown.ĭespite severe consequences on SKELETAL AND BONE MINERALIZATION (e.g. Many of the physiological changes observed upon chemical exposure are mediated through hormone receptors (e.g. (Colborn and Thayer, 2000 Jobling et al., 2002 Tyler et al., 1998). decreased fertility, birth deformities, abnormal metabolism / behavior / sexual characters, compromised immune system, cancers, etc. There is evidence that some of these compounds disturb the normal activity of endocrine systems (these compounds are referred as endocrine disrupters) by mimicking hormones (or altering their synthesis, metabolism or activity) and adverse biological effects have been noted in exposed animals e.g. estuarine and coastal waters), accumulating in significant amounts in the sediments. dioxins, detergents, pesticides, herbicides, antifouling paints, pharmaceutics, fertilizers, etc.) often come to rest in the AQUATIC ECOSYSTEM (e.g. Whether released into the atmosphere, onto land or into rivers, synthetic compounds produced by human activities (e.g.
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