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Synergistic effects of toxic elements on heat shock proteins.

Mahmood K, Jadoon S, Mahmood Q, Irshad M, Hussain J - Biomed Res Int (2014)

Bottom Line: The current knowledge regarding the interpretation of HSPs expression levels has been discussed in the present review.The candidature of heat shock proteins as biomarkers of toxicity is thus far unreliable due to synergistic effects of toxicants and other environmental factors.The adoption of heat shock proteins as "suit of biomarkers in a set of organisms" requires further investigation.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology, Government Post-Graduate College Asghar Mall, Rawalpindi, Pakistan.

ABSTRACT
Heat shock proteins show remarkable variations in their expression levels under a variety of toxic conditions. A research span expanded over five decades has revealed their molecular characterization, gene regulation, expression patterns, vast similarity in diverse groups, and broad range of functional capabilities. Their functions include protection and tolerance against cytotoxic conditions through their molecular chaperoning activity, maintaining cytoskeleton stability, and assisting in cell signaling. However, their role as biomarkers for monitoring the environmental risk assessment is controversial due to a number of conflicting, validating, and nonvalidating reports. The current knowledge regarding the interpretation of HSPs expression levels has been discussed in the present review. The candidature of heat shock proteins as biomarkers of toxicity is thus far unreliable due to synergistic effects of toxicants and other environmental factors. The adoption of heat shock proteins as "suit of biomarkers in a set of organisms" requires further investigation.

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Related in: MedlinePlus

HSP70 levels in Potamocorbula amurensis (means ± SD, n = 90) measured each month (n = 6–8 per station) from 07/1996 to 01/1998 (except 10/96, 1–3/97, and 10/97). One-way ANOVA and Tukey analysis revealed two major groups of sites: group A with sites 4.1 and 6.1 and group B with sites 8.1 and 12.5 (P < 0.001) [106].
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fig6: HSP70 levels in Potamocorbula amurensis (means ± SD, n = 90) measured each month (n = 6–8 per station) from 07/1996 to 01/1998 (except 10/96, 1–3/97, and 10/97). One-way ANOVA and Tukey analysis revealed two major groups of sites: group A with sites 4.1 and 6.1 and group B with sites 8.1 and 12.5 (P < 0.001) [106].

Mentions: Apart from the synergistic effects of toxicants, environmental factors such as temperature (Figure 5) [103], salinity [104], and oxygen supply [105] also influence the expression of HSPs and may also have a synergistic effect in combination with toxicants, thus making their consideration as biomarkers doubtful. For example, Cd exposure increased the HSP70 concentrations in marine clams, whereas salinity markedly lowered the same level in that species. A laboratory study regarding the effects of salinity on HSP70 concentrations indicated that exposure to 0.1 ppt salinity markedly lowered HSP70 concentrations in clams Potamocorbula amurensis compared with those exposed to higher salinities (Figure 6 and Table 2) [106]. Increasing the salinity from 5 to 25 per thousand resulted in lowering the toxicity and concentrations of the free metal ions (Figure 7). This effect has been regarded as the strongest for Cd and Pb, while such smaller effects were observed for Ni, Cu, and Zn [104]. The rate of uranium accumulation in the gill tissues of clam Corbicula fluminea was higher under hypoxia than normoxia. At the cellular level uranium instead of hypoxia induced the expression of multixenobiotic resistance protein. On the contrary, HSP60 was induced by hypoxia instead of uranium [107].


Synergistic effects of toxic elements on heat shock proteins.

Mahmood K, Jadoon S, Mahmood Q, Irshad M, Hussain J - Biomed Res Int (2014)

HSP70 levels in Potamocorbula amurensis (means ± SD, n = 90) measured each month (n = 6–8 per station) from 07/1996 to 01/1998 (except 10/96, 1–3/97, and 10/97). One-way ANOVA and Tukey analysis revealed two major groups of sites: group A with sites 4.1 and 6.1 and group B with sites 8.1 and 12.5 (P < 0.001) [106].
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4127286&req=5

fig6: HSP70 levels in Potamocorbula amurensis (means ± SD, n = 90) measured each month (n = 6–8 per station) from 07/1996 to 01/1998 (except 10/96, 1–3/97, and 10/97). One-way ANOVA and Tukey analysis revealed two major groups of sites: group A with sites 4.1 and 6.1 and group B with sites 8.1 and 12.5 (P < 0.001) [106].
Mentions: Apart from the synergistic effects of toxicants, environmental factors such as temperature (Figure 5) [103], salinity [104], and oxygen supply [105] also influence the expression of HSPs and may also have a synergistic effect in combination with toxicants, thus making their consideration as biomarkers doubtful. For example, Cd exposure increased the HSP70 concentrations in marine clams, whereas salinity markedly lowered the same level in that species. A laboratory study regarding the effects of salinity on HSP70 concentrations indicated that exposure to 0.1 ppt salinity markedly lowered HSP70 concentrations in clams Potamocorbula amurensis compared with those exposed to higher salinities (Figure 6 and Table 2) [106]. Increasing the salinity from 5 to 25 per thousand resulted in lowering the toxicity and concentrations of the free metal ions (Figure 7). This effect has been regarded as the strongest for Cd and Pb, while such smaller effects were observed for Ni, Cu, and Zn [104]. The rate of uranium accumulation in the gill tissues of clam Corbicula fluminea was higher under hypoxia than normoxia. At the cellular level uranium instead of hypoxia induced the expression of multixenobiotic resistance protein. On the contrary, HSP60 was induced by hypoxia instead of uranium [107].

Bottom Line: The current knowledge regarding the interpretation of HSPs expression levels has been discussed in the present review.The candidature of heat shock proteins as biomarkers of toxicity is thus far unreliable due to synergistic effects of toxicants and other environmental factors.The adoption of heat shock proteins as "suit of biomarkers in a set of organisms" requires further investigation.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology, Government Post-Graduate College Asghar Mall, Rawalpindi, Pakistan.

ABSTRACT
Heat shock proteins show remarkable variations in their expression levels under a variety of toxic conditions. A research span expanded over five decades has revealed their molecular characterization, gene regulation, expression patterns, vast similarity in diverse groups, and broad range of functional capabilities. Their functions include protection and tolerance against cytotoxic conditions through their molecular chaperoning activity, maintaining cytoskeleton stability, and assisting in cell signaling. However, their role as biomarkers for monitoring the environmental risk assessment is controversial due to a number of conflicting, validating, and nonvalidating reports. The current knowledge regarding the interpretation of HSPs expression levels has been discussed in the present review. The candidature of heat shock proteins as biomarkers of toxicity is thus far unreliable due to synergistic effects of toxicants and other environmental factors. The adoption of heat shock proteins as "suit of biomarkers in a set of organisms" requires further investigation.

Show MeSH
Related in: MedlinePlus