A Novel Heat Shock Protein 70-Based Vaccine Prepared from DC Tumor Fusion Cells: An Update.

We have developed an enhanced molecular chaperone-based vaccine through rapid isolation of Hsp70 peptide complexes after the fusion of tumor and dendritic cells (Hsp70.PC-F). In this approach, the tumor antigens are introduced into the antigen-processing machinery of dendritic cells through the cell fusion process, and thus we can obtain antigenic tumor peptides or their intermediates that have been processed by dendritic cells. Our results show that Hsp70.PC-F has increased immunogenicity compared to preparations from tumor cells alone and therefore constitutes an improved formulation of the chaperone protein-based tumor vaccine.

Heat Shock Proteins 70 Regulate Cell Motility and Invadopodia-Associated Proteins Expression in Oral Squamous Cell Carcinoma.

Background: Many studies have shown that diabetes is often closely related to oral squamous cell carcinoma (OSCC) occurrence and metastasis. Heat shock protein 70 (Hsp70) is a molecular chaperone related to diabetes complications. This study aims to investigate the role of Hsp70 in OSCC in expression of invadopodia-associated proteins. Methods: The expressions and correlation of HSP70, Hif1α, MMP2, MMP14, and cortactin were examined using bioinformatics analysis and verified by OSCC tissue microarrays. Assay in vitro was performed to analyze cell migration capacity after treatment with or without the HSP70 inhibitor. Results: The expressions of invadopodia-associated proteins were enhanced in OSCC tissues compared with paracarcinoma tissues and partially correlated with HSP70. Inhibiting HSP70 significantly decreased the cell viability, proliferation, and migration of OSCC cells. Conclusions: HSP70 may be involved in invadopodia-associated proteins in OSCC cells, which provides a promising method for treatment of OSCC metastasis.

Evaluation of exposure to environmental stressors on heat-shock protein 70 expression in normal oral keratinocyte cells.

OBJECTIVES: This study aimed to investigate the effect of cortisol, estrogen, and nicotine on heat shock protein 70 (HSP70) expressions at the level of normal oral mucosa keratinocyte cells. METHODS: In this in vitro study, keratinocytes were derived from rat oral cavity and cultured. Stressors were applied, including three groups, group 1: estrogen to simulate the postmenopausal state; group 2: cortisol to simulate psychological stress situation; group 3: nicotine to simulate smoking state. To determine the exact nature of keratinocyte cells, two surface markers, cytokeratin 18 and cytokeratin 14 were examined using the flow cytometry method. Then, the immunocytochemistry technique with three repetitions in each group was used to evaluate the HSP70 expression before and after applying the stressor. RESULTS: HSP70 expressions in the three stressor groups (estrogen, cortisol, and nicotine) were significantly lower than in the control group (p = 0.0001). The HSPs expression difference between cortisol and nicotine was statistically significant (p = 0.0001). Based on the results of MTT analysis, the mean cell viability of oral mucosal keratinocytes in all three intervention groups decreased compared to the control group. In the cortisol and nicotine groups, cell death was significantly higher than in the control group. In the estrogen group, cell death was significantly lower than in the nicotine group (p > 0.05). CONCLUSIONS: The specific concentrations of cortisol, estrogen, and nicotine as stressors can effectively reduce the expression of HSP70 in normal oral mucosal keratinocytes. These phenomena can be effective in cell viability and the development of oral lichen planus.

Argonaute proteins: Structural features, functions and emerging roles.

Argonaute proteins are highly conserved in almost all organisms. They not only involve in the biogenesis of small regulatory RNAs, but also regulate gene expression and defend against foreign pathogen invasion via small RNA-mediated gene silencing pathways. As a key player in these pathways, the abnormal expression and/or mis-modifications of Argonaute proteins lead to the disorder of small RNA biogenesis and functions, thus influencing multiply biological processes and disease development, especially cancer. In this review, we focus on the post-translational modifications and novel functions of Argonaute proteins in alternative splicing, host defense and genome editing.

The renal antioxidative effect of losartan involves heat shock protein 70 in proximal tubule cells.

Angiotensin II exerts a cardinal role in the pathogenesis of hypertension and renal injury via action of angiotensin II type 1 (AT1) receptors. Local renin-angiotensin system (RAS) activity is essential for the mechanisms mediating pathophysiological functions. Proximal tubular angiotensinogen and tubular AT1 receptors are augmented by intrarenal angiotensin II. Caveolin 1 plays an important role as a regulatory molecule for the compartmentalization of redox signaling events through angiotensin II-induced NADPH oxidase activation in the kidney. A role for the renin-angiotensin system in the development and/or maintenance of hypertension has been demonstrated in spontaneously hypertensive rats (SHRs). Many effects of angiotensin II are dependent on the AT1 stimulation of reactive oxygen species (ROS) production by NADPH oxidase. Angiotensin II upregulation stimulates oxidative stress in proximal tubules from SHR. The NADPH oxidase 4 (Nox4) is abundantly expressed in kidney proximal tubule cells. Induction of the stress response includes synthesis of heat shock protein 70, a molecular chaperone that has a critical role in the recovery of cells from stress and in cytoprotection, guarding cells from subsequent insults. HSP70 chaperones function in part by driving the molecular triage decision, which determines whether proteins enter the productive folding pathway or result in client substrate ubiquitination and proteasomal degradation. This review examines regulation of losartan-mediated antioxidative stress responses by the chaperone HSP70 in proximal tubule cells of spontaneously hypertensive rats.

Radiosensitization of HSF-1 Knockdown Lung Cancer Cells by Low Concentrations of Hsp90 Inhibitor NVP-AUY922.

The inhibition of heat shock protein 90 (Hsp90) a molecular chaperone for multiple oncogenic client proteins is considered as a promising approach to overcome radioresistance. Since most Hsp90 inhibitors activate HSF-1 that induces the transcription of cytoprotective and tumor-promoting stress proteins such as Hsp70 and Hsp27, a combined approach consisting of HSF-1 knockdown (k.d.) and Hsp90 inhibition was investigated. A specific HSF-1 k.d. was achieved in H1339 lung cancer cells using RNAi-Ready pSIRENRetroQ vectors with puromycin resistance. The Hsp90 inhibitor NVP-AUY922 was evaluated at low concentrations-ranging from 1-10 nM-in control and HSF-1 k.d. cells. Protein expression (i.e., Hsp27/Hsp70, HSF-1, pHSF-1, Akt, ß-actin) and transcriptional activity was assessed by western blot analysis and luciferase assays and radiosensitivity was measured by proliferation, apoptosis (Annexin V, active caspase 3), clonogenic cell survival, alkaline comet, γH2AX, 53BP1, and Rad51 foci assays. The k.d. of HSF-1 resulted in a significant reduction of basal and NVP-AUY922-induced Hsp70/Hsp27 expression levels. A combined approach consisting of HSF-1 k.d. and low concentrations of the Hsp90 inhibitor NVP-AUY922 reduces the Hsp90 client protein Akt and potentiates radiosensitization, which involves an impaired homologous recombination mediated by Rad51. Our findings are key for clinical applications of Hsp90 inhibitors with respect to adverse hepatotoxic effects.

Genomewide identification and analysis of heat-shock proteins 70/110 to reveal their potential functions in Chinese soft-shelled turtle Pelodiscus sinensis.

Heat-shock proteins 70/110 (Hsp70/110) are vital molecular chaperones and stress proteins whose expression and production are generally induced by extreme temperatures or external stresses. The Hsp70/110 family is largely conserved in diverse animals. Although many reports have studied and elaborated on the characteristics of Hsp70/110 in various species, the systematic identification and analysis of Hsp70/110 are still poor in turtles. In this study, a genomewide search was performed, and 18 candidate PsHSP70/110 family genes were identified in Chinese soft-shelled turtle, Pelodiscus sinensis. These PsHSP70/110 proteins contained the conserved "heat shock protein 70" domain. Phylogenetic analysis of PsHSP70/110 and their homologs revealed evolutionary conservation of Hsp70/110 across different species. Tissue-specific expression analysis showed that these PsHSP70/110 genes were differentially expressed in different tissues of P. sinensis. Furthermore, to examine the putative biological functions of PsHSP70/110, the dynamic expression of PsHSP70/110 genes was analyzed in the testis of P. sinensis during seasonal spermatogenesis following germ cell apoptosis. Notably, genes such as PsHSPA1B-L, PsHSPA2, and PsHSPA8 were significantly upregulated in P. sinensis testes along with a seasonal decrease in apoptosis. Protein interaction prediction revealed that PsHSPA1B-L, PsHSPA2, and PsHSPA8 may interact with each other and participate in the MAPK signaling pathway. Moreover, immunohistochemical analysis showed that PsHSPA1B-L, PsHSPA2, and PsHSPA8 protein expression was associated with seasonal temperature variation. The expression profiling and interaction relationships of the PsHSPA1B-L, PsHSPA2, and PsHSPA8 proteins implied their potential roles in inhibiting the apoptosis of germ cells in P. sinensis. These results provide insights into PsHSP70/110 functions and will serve as a rich resource for further investigation of HSP70/110 family genes in P. sinensis and other turtles.

The Hsp70 Gene Family in Boleophthalmus pectinirostris: Genome-Wide Identification and Expression Analysis under High Ammonia Stress.

Heat shock proteins 70 have triggered a remarkable large body of research in various fishes; however, no genome-wide identification and expression analysis has been performed on the Hsp70 gene family of Boleophthalmus pectinirostris. In this study, we identified 20 Hsp70 genes within the genome of B. pectinirostris and provided insights into their response to high environmental ammonia (HEA) stress. Positive selection on stress response genes and expansion of hspa1a and hspa1a-like genes might be related to terrestrial adaptations in this species. The expression patterns of the Hsp70 gene family in the gill and liver of B. pectinirostris under HEA stress were studied by examining transcriptome data. The results showed that most Hsp70 genes were downregulated after high concentration ammonia exposure. The downregulation may be related to the hypoxic condition of the tissues.

Expression of Heat Shock Protein 70 in Oral Epithelial Dysplasia and Oral Squamous Cell Carcinoma: An Immunohistochemical Study.

INTRODUCTION: Heat shock proteins are biomarkers regulating the degree of differention and aggressiveness in oral carcinogenesis. The study was carried out to evaluate the expression of HSP 70 in histological grades of epithelial dysplasia and oral squamous cell carcinoma using immunohistochemistry. METHODOLOGY: A sample of 40, which included 10 (Normal), 15 (epithelial dysplasia) and 15 (oral squamous cell carcinoma) were selected. The biopsy samples were stained using H and E staining and HSP 70 IHC. RESULTS: There was a statistical significant difference in expression of HSP 70 between normal oral mucosal tissue, leukoplakia and OSCC. DISCUSSION AND CONCLUSION: This study concludes the critical role of HSP70 as an oncogene in the development of oral cancer. HSP70 inhibition is, therefore a promising therapeutic approach for cancer treatment.

The Level Short Chain Fatty Acids and HSP 70 in Colorectal Cancer and Non-Colorectal Cancer.

INTRODUCTION: Microbial involvement in colorectal cancer (CRC) is now well established. Short Chain Fatty Acids (SCFA) is the main products of anaerobic microbial fermentation in the large intestine and affects colonic health. SCFA mainly produced as microbial metabolites, acetate, propionate, and butyrate acids. Several in vitro studies showed that butyrate induce expression of heat shock protein (HSP) 70 that has function in the beginning of apoptosis. AIM: The aim of this study was investigating the differences level SCFA and HSP 70 expression in CRC compared with non-CRC patients. MATERIAL AND METHODS: The study consists of 14 patients diagnosed with CRC and 14 non-CRC patients. Stool sample were analyzed for SCFA (acetate, propionate, and butyrate acids) with gas chromatography and the result is given as µg/mL and the protein expression of HSP70 was determined by immunohistochemistry (IHC) and haematoxylin-eosin staining to determine the morphological changes in colon tissue. RESULTS: We found that CRC patients had lower level of acetate, propionate and butyrate acids than non-CRC. Whereas in CRC patients, the mean concentration of acetate was 8,55 µg/mL, propionate was 5,61 µg/mL and butyrate acids were 3,79 µg/mL respectively (all P < 0.05). And among the samples of patients with colorectal cancer was obtained the highest expression of HSP-70. CONCLUSIONS: Short chain fatty acids were indirectly contributed in the role of pathogenesis in CRC despite another factor could affect for this disease.

Glycemic, inflammatory and oxidative stress responses to different high-intensity training protocols in type 1 diabetes: A randomized clinical trial.

AIMS: To investigate the effects of high-intensity interval training (HIIT) and/or strength training (ST) on inflammatory, oxidative stress (OS) and glycemic parameters in type 1 diabetes (T1DM) patients. METHODS: After a 4-week control period, volunteers were randomly assigned to 10-week HIIT, ST or ST + HIIT protocol, performed 3×/week. Blood biochemistry, anthropometric, strength and cardiopulmonary fitness variables were assessed. Outcomes were analyzed via generalized estimating equations (GEE), with Bonferroni post hoc analysis. RESULTS: ST, HIIT and ST + HIIT improved glycemic (HbA1c and fasting glucose) and antioxidant parameters (total antioxidant capacity, catalase and superoxide dismutase activities), but not plasma inflammatory (C-reactive protein, TNF-α and IL-10) or OS markers (thiobarbituric acid-reactive substances, 8-hydroxy-2-deoxyguanosine and oxLDL) levels. Noteworthy, interventions reduced soluble receptors for advanced glycation end products levels. However, intracellular heat shock protein 70 content increased only after HIIT. While daily insulin dosage decreased only in the ST + HIIT group, all training models induced anthropometric and functional benefits. CONCLUSIONS: Similar benefits afforded by ST, HIIT or ST + HIIT in T1DM people are associated with enhanced antioxidant systems and glucose-related parameter, even in a few weeks. From a practical clinical perspective, the performance of ST + HIIT may be advised for additional benefits regarding insulin dosage reduction.

Nonspecific stress response to temperature increase in Gammarus lacustris Sars with respect to oxygen-limited thermal tolerance concept.

The previously undescribed dynamics of the heat shock protein HSP70 and subsequent lipid peroxidation products have been assessed alongside lactate dehydrogenase activity for Gammarus lacustris Sars, an amphipod species from the saltwater Lake Shira (Republic of Khakassia). Individuals were exposed to a gradual temperature increase of 1 °C/hour (total exposure duration of 26 hours) starting from the mean annual temperature of their habitat (7 °C) up to 33 °C. A complex of biochemical reactions occurred when saltwater G. lactustris was exposed to the gradual changes in temperature. This was characterized by a decrease in lactate dehydrogenase activity and the launching of lipid peroxidation. The HSP70 level did not change significantly during the entire experiment. In agreement with the concept of oxygen-limited thermal tolerance, an accumulation of the most toxic lipid peroxides (triene conjugates and Schiff bases) in phospholipids occurred at the same time and temperature as the accumulation of lactate. The main criterion overriding the temperature threshold was, therefore, the transition to anaerobiosis, confirmed by the elevated lactate levels as observed in our previous associated study, and by the development of cellular stress, which was expressed by an accumulation of lipid peroxidation products. An earlier hypothesis, based on freshwater individuals of the same species, has been confirmed whereby the increased thermotolerance of G. lacustris from the saltwater lake was caused by differences in energy metabolism and energy supply of nonspecific cellular stress-response mechanisms. With the development of global climate change, these reactions could be advantageous for saltwater G. lacustris. The studied biochemical reactions can be used as biomarkers for the stress status of aquatic organisms when their habitat temperature changes.

Changes in chosen immune system indicators and the level of HSP-70 after single whole-body cryostimulation in healthy men.

AIM OF THE STUDY: The aim of our research was to examine the influence of single whole-body cryostimulation (WBC) on chosen immune system indicators including the heat shock protein HSP-70. MATERIAL AND METHODS: The study was carried out among ten young and healthy men (mean age 22.4 ±1.65, with a body mass index of 22.91 ±2.39 kg/m2). The participants were subjected to single whole-body cryostimulation (at -130°C temperatures) in a special cryogenic chamber for 3 minutes. Blood samples were collected three times: before cryostimulation, 30 minutes and 24 hours after WBC. Immunoglobulins (IgA, IgG, IgM), interleukins (IL-6, IL-10, IL-1ß) and the heat shock protein (HSP-70) were determined in the blood serum. RESULTS: As a result of a single exposure to cryogenic temperatures, a significant increase in the level of IL-6 was observed 30 minutes after the WBC (p < 0.05) and a decrease in the level of HSP-70 24 hours after the treatment (p < 0.05). There were no significant changes in the level of interleukins (IL-10, IL-1ß) or immunoglobulins 30 minutes after a single WBC treatment or 24 hours later. CONCLUSIONS: Detailed analysis of the issue shows that a single application of whole-body cryostimulation causes a small, modulating effect on the IL-6 level. Single whole-body cryostimulation treatment has also a slight silencing effect on the HSP-70 level in healthy, young men. Reduction in the concentration of HSP-70 24 hours after WBC may indicate lack of the damaging impact on the spatial structure of the protein due to cryogenic temperatures.

A Novel Heat Shock Protein 70-based Vaccine Prepared from DC-Tumor Fusion Cells.

We have developed an enhanced molecular chaperone-based vaccine through rapid isolation of Hsp70 peptide complexes after the fusion of tumor and dendritic cells (Hsp70.PC-F). In this approach, the tumor antigens are introduced into the antigen processing machinery of dendritic cells through the cell fusion process and thus we can obtain antigenic tumor peptides or their intermediates that have been processed by dendritic cells. Our results show that Hsp70.PC-F has increased immunogenicity compared to preparations from tumor cells alone and therefore constitutes an improved formulation of chaperone protein-based tumor vaccine.

[Intervention of edaravone against renal injury induced by acute paraquat poisoning in rats].

Objective: To investigate the dynamic change of paraquant-induced kidney injury in rats and the protective effect of edaravone. Methods: Eighty SD rats were randomly divided into 4 groups: the normal control group, paraquat poisoning group, edaravone treatment group and edaravone control group. The normal control group of 8 rats were given 1 ml of 0.9% sodium chloride through the abdominal cavity, and the same amount of fluid into the abdominal cavity after 30 minutes. The paraquat poisoning group of 24 rats were given 1 ml of paraquat solution (20 mg/kg) through the abdominal cavity to build poisoning models, and the same amount of 0.9% sodium chloride was injected into the abdominal cavity after 30 minutes. The edaravone treatment group of 24 rats were given edaravone (5 mg/kg) through the abdominal cavity after 30 minutes when the poisoning models were set up. The edaravone control group of 24 rats were given 1 ml of 0.9% sodium chloride through the abdominal cavity, and edaravone (5 mg/kg) was injected into the abdominal cavity after 30 minutes. In addition to the normal control group, the other groups processed 1 times a day to mantain 7 d. On 1, 3, 7, 21 d several rats in each group were excuted and the kidney tissue and serum samples were collected, then each pathological changes of the kidney were observed with light microscopy. Serum creatinine, KIM-1, NGAL were measured by ELISA, the expression of HSP70 protein in kidney were observed with immunohistochemical staining. Results: The pathological examination reveald that the damage of kidney tissue in the paraquat group was the most serious on 3 d, and the damage was consistently alleviated in edaravone treatment group at the same time, renal fibrosisn was unseen in each group until 21 d. Compared with normal control group, there was no statistically significant in edaravone control group (P>0.05) . The KIM-1 in blood and kidney in paraquat poisoning group were markedly increased in 1 d (P<0.05) . The NGAL in blood and creatinine were markedly increased in d7 (P<0.05) . The NGAL in kidney increased over time, but had no statistically difference with the control group (P>0.05) .Compared with paraquat poisoning group, the serum creatinine, KIM-1 in blood and kidney, the KIM-1 in kidney had decreased significantly in edaravone treatment group (P<0.05) . The NGAL in kidney has no statistically significant compared with the poisoning group (P>0.05) . HSP70 expression of kidney tissue in edaravone treatment group had significantly increased in d3 compared with the paraquat poisoning group (P<0.05) . Conclusion: Edaravone can prompt a significant rise of HSP70 in kidney tissue, reduce KIM-1 and NGAL levels, and play a protective role in kidney injury of acute paraquat poisoning.

Molecular analysis of Hsp70 mechanisms in plants and their function in response to stress.

Studying the strategies of improving abiotic stress tolerance is quite imperative and research under this field will increase our understanding of response mechanisms to abiotic stress such as heat. The Hsp70 is an essential regulator of protein having the tendency to maintain internal cell stability like proper folding protein and breakdown of unfolded proteins. Hsp70 holds together protein substrates to help in movement, regulation, and prevent aggregation under physical and or chemical pressure. However, this review reports the molecular mechanism of heat shock protein 70 kDa (Hsp70) action and its structural and functional analysis, research progress on the interaction of Hsp70 with other proteins and their interaction mechanisms as well as the involvement of Hsp70 in abiotic stress responses as an adaptive defense mechanism.

Intervention of edaravone against renal injury induced by acute paraquat poisoning in rats / 中华劳动卫生职业病杂志

Objective@#To investigate the dynamic change of paraquant-induced kidney injury in rats and the protective effect of edaravone.@*Methods@#Eighty SD rats were randomly divided into 4 groups: the normal control group, paraquat poisoning group, edaravone treatment group and edaravone control group. The normal control group of 8 rats were given 1 ml of 0.9% sodium chloride through the abdominal cavity, and the same amount of fluid into the abdominal cavity after 30 minutes. The paraquat poisoning group of 24 rats were given 1 ml of paraquat solution (20 mg/kg) through the abdominal cavity to build poisoning models, and the same amount of 0.9% sodium chloride was injected into the abdominal cavity after 30 minutes. The edaravone treatment group of 24 rats were given edaravone (5 mg/kg) through the abdominal cavity after 30 minutes when the poisoning models were set up. The edaravone control group of 24 rats were given 1 ml of 0.9% sodium chloride through the abdominal cavity, and edaravone (5 mg/kg) was injected into the abdominal cavity after 30 minutes. In addition to the normal control group, the other groups processed 1 times a day to mantain 7 d. On 1, 3, 7, 21 d several rats in each group were excuted and the kidney tissue and serum samples were collected, then each pathological changes of the kidney were observed with light microscopy. Serum creatinine, KIM-1, NGAL were measured by ELISA, the expression of HSP70 protein in kidney were observed with immunohistochemical staining.@*Results@#The pathological examination reveald that the damage of kidney tissue in the paraquat group was the most serious on 3 d, and the damage was consistently alleviated in edaravone treatment group at the same time, renal fibrosisn was unseen in each group until 21 d. Compared with normal control group, there was no statistically significant in edaravone control group (P>0.05) . The KIM-1 in blood and kidney in paraquat poisoning group were markedly increased in 1 d (P<0.05) . The NGAL in blood and creatinine were markedly increased in d7 (P<0.05) . The NGAL in kidney increased over time, but had no statistically difference with the control group (P>0.05) .Compared with paraquat poisoning group, the serum creatinine, KIM-1 in blood and kidney, the KIM-1 in kidney had decreased significantly in edaravone treatment group (P<0.05) . The NGAL in kidney has no statistically significant compared with the poisoning group (P>0.05) . HSP70 expression of kidney tissue in edaravone treatment group had significantly increased in d3 compared with the paraquat poisoning group (P<0.05) .@*Conclusion@#Edaravone can prompt a significant rise of HSP70 in kidney tissue, reduce KIM-1 and NGAL levels, and play a protective role in kidney injury of acute paraquat poisoning.

Acetylcholinesterase (AChE) and heat shock proteins (Hsp70) of gypsy moth (Lymantria dispar L.) larvae in response to long-term fluoranthene exposure.

Polycyclic aromatic hydrocarbons (PAHs) may affect biochemical and physiological processes in living organisms, thus impairing fitness related traits and influencing their populations. This imposes the need for providing early-warning signals of pollution. Our study aimed to examine changes in the activity of acetylcholinesterase (AChE) and the concentration of heat shock proteins (Hsp70) in homogenates of brain tissues of fifth instar gypsy moth (Lymantria dispar L.) larvae, exposed to the ubiquitous PAH, fluoranthene, supplemented to the rearing diet. Significantly increased activity of AChE in larvae fed on the diets with high fluoranthene concentrations suggests the necessity for elucidation of the role of AChE in these insects when exposed to PAH pollution. Significant induction of Hsp70 in gypsy moth larvae reared on the diets containing low fluoranthene concentrations, indicate that changes in the level of Hsp70 might be useful as an indicator of pollution in this widespread forest species.

Modulation of the response to stress factors of Xerolycosa nemoralis (Lycosidae) spiders living in contaminated environments.

The rapid development of industry has caused widespread pollution in the environment, which has a negative impact on living organisms. Spiders belong to the group of animals that can exist in these anthropogenically changed areas. This is probably due to the development of tolerance mechanisms in these organisms. The impact of long-term pollution on the development of the pre-adaptation to various stress factors in spiders is unknown. In this paper, we show that living in polluted areas affects the modulation of the response to other stress factors through changes in the Hsp70 level. We observed a positive reaction to heat shock in all of the experimental groups, which was expressed by an increase in Hsp70 synthesis compared to the control. The analysis of the protein level, which was a manifestation of the pre-adaptation, was dependent on the degree of pollution on the study sites, the sexes and the type of bioassay that was performed. Our results demonstrate the reaction of spiders living in contaminated areas to the presence of additional stressors. We anticipate our results will be another voice in the discussion on the use of Hsp70 as a stress biomarker in environmental biomonitoring.

Effect of dietary manganese on antioxidant status and expression levels of heat-shock proteins and factors in tissues of laying broiler breeders under normal and high environmental temperatures.

To investigate the effect of Mn on antioxidant status and expression levels of heat-shock proteins/factors in tissues of laying broiler breeders subjected to heat challenge, we used a completely randomised design (n 6) with a factorial arrangement of 2 environmental temperatures (normal, 21 (sem 1)°C and high, 32 (sem 1)°C)×3 dietary Mn treatments (an Mn-unsupplemented basal diet (CON), or a basal diet supplemented with 120 mg Mn/kg diet as inorganic Mn sulphate (iMn) or organic Mn proteinate (oMn)). There were no interactions (P>0·10) between environmental temperature and dietary Mn in all of the measured indices. High temperature decreased (P<0·003) Mn content, and also tended (P=0·07) to decrease copper zinc superoxide dismutase (CuZnSOD) activity in the liver and heart. However, an increased manganese superoxide dismutase (MnSOD) activity (P<0·05) and a slight increase of malondialdehyde level (P=0·06) were detected in breast muscle. Up-regulated (P<0·05) expression levels of heat-shock factor 1 (HSF1) and HSF3 mRNA and heat-shock protein 70 (HSP70) mRNA and protein were found in all three tissues. Broiler breeders fed either iMn or oMn had higher tissue Mn content (P<0·0001), heart MnSOD and CuZnSOD activities (P<0·01) and breast muscle MnSOD protein levels (P<0·05), and lower (P<0·05) breast muscle HSP70 mRNA and protein levels than those fed CON. Broiler breeders fed oMn had higher (P<0·03) bone Mn content than those fed iMn. These results indicate that high temperature decreases Mn retention and increases HSP70 and HSF1, HSF3 expression levels in tissues of laying broiler breeders. Furthermore, dietary supplementation with Mn in either source may enhance heart antioxidant ability and inhibit the expression of HSP70 in breast muscle. Finally, the organic Mn appears to be more available than inorganic Mn for bone in laying broiler breeders regardless of environmental temperatures.