Stress proteins exposure

Cold stress may induce synthesis of heat-shock (stress) proteins. Exposure of cells to cold shock may lead to the induction of one or more of the classes of molecular chaperones that also are induced by heat shock. This is strong evidence that low temperature, like high temperature, can lead to non-native protein structures in vivo and, therefore, to the requirement for enhanced chaperoning activity. Induction of cold-induced protein chaperones has been seen in bacteria (Salotra et al., 1995), in whole organism studies of ectothermic animals (Petersen et al., 1990 Yocum et ah, 1991),... 

It has been demonstrated in other cell types that lutein can inhibit expression of MMPs and/ or activity (Philips et al., 2007). For example, in dermal fibroblasts lutein inhibits expression of MMP-1 and decreases levels of MMP-2 protein (Philips et al., 2007). In melanoma cells, lutein inhibits MMP-1 expression while stimulating TIMP-2 (Philips et al., 2007). Moreover it has been shown that lutein inhibits elastin expression in fibroblasts subjected to oxidative stress by exposure to ultraviolet light (Philips et al., 2007). These results clearly indicate that lutein can play an important role in remodeling of the extracellular matrix. 

Exposure of cells to elevated temperatures, or heat shock, induces the transcription and translation of a set of proteins known as the heat-shock proteins (HSPs) or the stress proteins. This event usually occurs with the concomitant inhibition of biosynthesis of other cellular components. The response is believed to be an attempt by the cells to protect themselves from injury, and there is some evidence to indicate that it may also be linked to oxidative stress. Evidence in favour of this idea comes from observations such as the following ... 

Heat-shock protein is part of a repair mechanism which involves protection and repair of cells following cellular damage due to exposure to a wide variety of stressors. Heat-shock stress protein HSP 70 has the capability to restore the damaged proteins under adverse conditions. Significant increases in the H S P 70 may directly interfere with ongoing cellular processes or may alter the function of the cells, whereas alowto... 

His PhD was awarded from the University of North Texas, where he studied the stress protein response in fish exposed to diverse contaminants via laboratory and field exposures. 

When organisms are confronted with sudden changes such as exposure to potentially toxic substances (heavy metal ions) or the onset of starvation, these stimulations induce the production of the so-called stress responsive proteins. The most thoroughly studied stress proteins include the heat-shock proteins (HSP), the induction of which is a highly conserved response across genera. 

Discuss the inhibition of specific enzymes, enzyme synthesis induction, stress proteins, DNA and chromosomal damage, immunological endpoints, and nutritional state as biomarkers of exposure to xenobiotics. 

Eckwert, H., Alberti, G. and Kohler, H.-R. (1997) The induction of stress proteins (hsp) in Oniscus asellus (Isopoda) as a molecular marker of multiple heavy metal exposure. 1. Principles and toxicological assessment. Ecotoxicology, 6, 249-262. 

Veldhuizen-Tsoerkan, M.B., Holwerda, D.A., van der Mast, C.A. and Zandee, D.I. (1991a) Synthesis of stress proteins under normal and heat shock conditions in gill tissue of sea mussels (Mytilus edulis) after chronic exposure to cadmium. Comp. Biochem. Physiol., 100C, 699-706. 

Alcohol toxicity has not been the primary focus of investigations using zebrafish. Instead, zebrafish have been treated with very high doses of alcohol in order to perturb a particular developmental and/or signaling pathway of interest. Exposure of zebrafish embryos to alcohol causes cyclopia, craniofacial abnormalities, and alters gene expression in the ventral aspects of the fore- and mid-brain . Alcohol exposure of zebrafish embryos also induces stress proteins , developmental... 

Confirmation of some link between the stress of exposure to extremes of temperature and the stress of physical injury is given by the work of Blatt and Kerkay (B9), who found plasma protein changes similar to those described above as following physical injury when men were exposed for 3 weeks to temperatures of less than 10°C. Exposure to heat of almost 60°C, however, produced very little change in plasma protein patterns, only a slight fall in globulin being noted. 

Taketani, S., Kohno, H., Yoshinaga, T., and Tokunaga, R. (1989). The human 32-kDa stress protein induced by exposure to arsenite and cadmium ions is heme oxygenase. FEBS Lett. 245, 173-176. 

Exposure of the human cell line A549 to 1-10 liM CdCb triggered a slight accumulation of glutathione, whereas this compound was depleted after exposure to concentrations of 25-100/tM of cadmium (Gaubin et al. 2000). treatment of cells with 20 or 40 mM W-acetyl-L-cysteine, which traps free radicals, was found to increase by 30 % the glutathione level and to suppress the overexpression of stress proteins. 

To determine whether 4-hydroxynonenal could account for the acute effects of ozone on human alveolar macrophages, Hamilton jr. et al. (1998) exposed healthy, non-smoking volunteers to 0.4 ppm ozone or air for 1 h with exercise (each subject served as his/her own control). Six hours after ozone exposure, cells obtained by airway lavage were examined for apoptotic cell injury, presence of 4-hydroxynonenal adducts, and expression of stress proteins. Significant apoptosis was evident in airway lung cells after ozone exposure. Western analysis demonstrated an increase in a 32-kDa 4-hydroxynonenal protein adduct and a number of stress proteins, viz., 72-kDa heat shock protein and ferritin, in alveolar macrophages after ozone exposure. All these effects could be replicated by in vitro exposure of alveolar macrophages to 4-hydroxy-nonenal. 

Bournias-Vardiabasis et al. (1990) exposed Drosophila embryonic cells to a number of metal ions that had previously been reported to act as teratogens in mammalian systems. Although the induced protein patterns varied between different metals, zinc induced a pattern similar to that produced by classical teratogens. Roccheri et al. (1988) reported that treatment of sea urchin embryos with zinc induced the same stress proteins as those observed in heat-treated embryos. These investigators found that zinc treatment induced a protracted synthesis of the stress proteins relative to heat. This finding might be explained by the prolonged exposure of the sea urchin embryos to zinc in the culture medium. Unlike heat shock, zinc treatment did not inhibit overall protein synthesis or induce thermotolerance in these zinc-treated sea urchin embryos. 

Data generated from a study of lead-induced synthesis of stress proteins illustrated that different metals have both common and individual effects on expression of stress proteins. Lead-induced stress protein synthesis was unusual in that it did not share the properties of metals, such as cadmium and arsenite, to mimic the effects of heat (Shelton et al. 1986). Rather, lead induced two minor classes of proteins. In this study, exposure of primary rat kidney epithelial cells and rat fibroblasts to lead glutamate induced synthesis of two grps and a protein of 32 kDa, which was shown to... 

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