BACKGROUND: Enzalutamide, a second-generation androgen receptor (AR) pathway inhibitor, is widely used in the treatment of castration-resistant prostate cancer. However, after a period of enzalutamide treatment, patients inevitably develop drug resistance. In this study, we characterized leucine-rich repeated G-protein-coupled receptor 5 (LGR5) and explored its potential therapeutic value in prostate cancer. METHODS: A total of 142 pairs of tumor and adjacent formalin-fixed paraf-fin-embedded tissue samples from patients with prostate cancer were collected from the Pathology Department at Sun Yat-sen Memorial Hos-pital. LGR5 was screened by sequencing data of enzalutamide-resistant cell lines combined with sequencing data of lesions with different Gleason scores from the same patients. The biological function of LGR5 and its effect on enzalutamide resistance were investigated in vitro and in vivo . Glutathione-S-transferase (GST) pull-down, coimmunoprecipitation, Western blotting, and immunofluorescence assays were used to explore the specific binding mechanism of LGR5 and related pathway changes. RESULTS: LGR5 was significantly upregulated in prostate cancer and negatively correlated with poor patient prognosis. Overexpression of LGR5 promoted the malignant progression of prostate cancer and reduced sensitivity to enzalutamide in vitro and in vivo . LGR5 promoted the phosphorylation of glycogen synthase kinase-3β (GSK-3β) by binding heat shock protein 90,000 alpha B1 (HSP90AB1) and mediated the activation of the Wingless/integrated (WNT)/β-catenin signaling pathway. The increased β-catenin in the cytoplasm entered the nucleus and bound to the nuclear AR, promoting the transcription level of AR, which led to the enhanced tolerance of prostate cancer to enzalutamide. Reducing HSP90AB1 binding to LGR5 significantly enhanced sensitivity to enzalutamide. CONCLUSIONS LGR5 directly binds to HSP90AB1 and mediates GSK-3β phosphorylation, promoting AR expression by regulating the WNT/β-catenin signaling pathway, thereby conferring resistance to enzalutamide treatment in prostate cancer.
Male ; Humans ; Phenylthiohydantoin/pharmacology* ; Benzamides ; Receptors, G-Protein-Coupled/genetics* ; Nitriles ; Cell Line, Tumor ; HSP90 Heat-Shock Proteins/metabolism* ; Drug Resistance, Neoplasm/genetics* ; Prostatic Neoplasms/drug therapy* ; beta Catenin/metabolism* ; Receptors, Androgen/genetics* ; Animals ; Mice ; Wnt Signaling Pathway/physiology*

Objective To explore the effect of rehmanniae radix extract(RRE)on chondrocyte apoptosis in the rabbit model of knee osteoarthritis(KOA)by regulating the miR-485-5p/heat shock protein 90 beta family member 1(Hsp90b1)axis.Methods New Zealand rabbits were randomly assigned into control,KOA,low-dose RRE,medium-dose RRE,high-dose RRE,celecoxib,high-dose RRE+antagonist control,and high-dose RRE+miR-485-5p antagonist groups,with 12 rabbits in each group.Rabbits in other groups except the control group were modeled for KOA with the improved Hulth method.After modeling for 8 weeks,the rabbits were administrated with corresponding agents for 4 weeks.The changes in the activity rating of rabbits were recorded.ELISA was employed to measure the levels of tumor necrosis factor-α(TNF-α)and interleukin(IL)-6 in the serum.Safranine O-fast green staining was conducted to reveal the pathological changes in the cartilage tissue and Mankin scoring was performed.TUNEL was employed to detect chondrocyte apoptosis.Real-time fluorescence quantitative PCR was performed to determine the expression of miR-485-5p in the cartilage tissue.Western blot was employed to determine the protein levels of Hsp90b1,cleaved cysteinyl aspartate-specific proteinase-3(Caspase-3),and Bcl2-associated-X(Bax)in the cartilage tissue.The dual-luciferase reporter assay was employed to examine the relationship between miR-485-5p and Hsp90b1.Results Compared with the control group,the KOA group showed down-regulated expression of miR-485-5p,elevated levels of TNF-α and IL-6 in the serum,cartilage erosion and losses,and increases in activity rating,Mankin score,chondrocyte apoptosis rate,and protein levels of Hsp90b1,cleaved Caspase-3,and Bax(all P<0.001).Compared with the KOA group,RRE at low,medium,and high doses,and celecoxib up-regulated the expression of miR-485-5p,lowered the levels of TNF-α and IL-6 in the serum,alleviated the pathological damage to the cartilage tissue,and decreased the activity rating,Mankin score,chondrocyte apoptosis rate,and protein levels of Hsp90b1,cleaved Caspase-3,and Bax(all P<0.05).Compared with the high-dose RRE group and the high-dose RRE+antagonist control group,high-dose RRE+miR-485-5p antagonist down-regulated the expression of miR-485-5p,elevated the levels of TNF-α and IL-6 in the serum,exacerbated the pathological damage to the cartilage tissue,and increased the activity rating,Mankin score,chondrocyte apoptosis rate,and protein levels of Hsp90b1,cleaved Caspase-3,and Bax(all P<0.05).The results indicated that there was a targeted regulatory relationship between miR-485-5p and Hsp90b1.Conclusion RRE may inhibit the expression of Hsp90b1 by up-regulating miR-485-5p,thereby inhibiting chondrocyte apoptosis in the rabbit model of KOA.
Animals ; Rabbits ; Apoptosis/drug effects* ; Chondrocytes/pathology* ; Osteoarthritis, Knee/drug therapy* ; MicroRNAs/metabolism* ; Rehmannia/chemistry* ; Disease Models, Animal ; Tumor Necrosis Factor-alpha/blood* ; Plant Extracts/pharmacology* ; Interleukin-6/blood* ; HSP90 Heat-Shock Proteins/metabolism* ; Male ; Drugs, Chinese Herbal/pharmacology*

This study aimed to investigate the potential role of Colquhounia Root Tablets against bone destruction in rheumatoid arthritis(RA) and its molecular mechanism. The study used ultra-performance liquid chromatography-mass spectrometry to analyze the major components of Colquhounia Root Tablets and predicted its candidate target gene set based on the major components. The key targets of RA bone destruction were obtained through GeneCards and the Database of Genetics and Medical Literature(OMIM), protein-protein interaction(PPI) network was constructed, and the key targets were identified by topological analysis. The molecular mechanism of Colquhounia Root Tablets against RA bone destruction was further revealed using Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment analysis. The effects of Colquhounia Root Tablets on macrophage viability was assessed by MTS assay and screened for non-toxic concentrations. A model of receptor activator of nuclear factor-κB(RANKL) induced osteoclast differentiation in vitro was constructed. Colquhounia Root Tablets were used to observe the formation and differentiation of osteoclasts by tartrate-resistant acid phosphatase(TRAP) staining and fibrous actin(F-actin) staining, and the effects of Colquhounia Root Tablets on the changes of core target proteins in the osteoclast differentiation system were detected by immunofluorescence and Western blot. The results showed that the main components of Colquhounia Root Tablets included 14 compounds such as triptolide, celastrol, and triptophenolide. Further network analysis revealed that heat-shock protein 90(HSP90) was the key target gene of Colquhounia Root Tablets for anti-RA bone destruction. TRAP staining and F-actin staining showed that the number and area of TRAP-positive polymorphonuclear cells, as well as actin rings, were reduced in a dose-dependent manner after the intervention of Colquhounia Root Tablets(P<0.01). Western blot results showed that the expression of HSP90 protein was significantly reduced after intervention with Colquhounia Root Tablets at 20 and 40 μg·mL~(-1)(P<0.01); Colquhounia Root Tablets at 10 μg·mL~(-1) could significantly decrease the expression of necrosis factor receptor associated molecule 6(TRAF6) and nuclear factor of activated T cells 1(NFATc1) proteins(P<0.01); moreover, all doses of Colquhounia Root Tablets significantly reduced the expression of osteoclast differentiation marker proteins matrix metalloproteinase 9(MMP9) and cathepsin K(CTSK)(P<0.01).Immunofluorescence results further confirmed that Colquhounia Root Tablets significantly inhibited HSP90 and CTSK levels, as well as NFATc1 activation in osteoblasts. In conclusion, the present study confirmed that Colquhounia Root Tablets may inhibit RANKL-induced osteoclast differentiation by regulating the key target of HSP90, thus exerting an anti-RA bone destruction effect, which will provide a new idea for Colquhounia Root Tablets to prevent and treat bone destruction in rheumatoid arthritis.
Osteoclasts/metabolism* ; Mice ; Animals ; Cell Differentiation/drug effects* ; HSP90 Heat-Shock Proteins/genetics* ; Drugs, Chinese Herbal/chemistry* ; Plant Roots/chemistry* ; Humans ; Arthritis, Rheumatoid/physiopathology* ; Protein Interaction Maps/drug effects*

Objective: To investigate the effects and mechanism of negative pressure microenvironment on the neogenesis of human umbilical vein endothelial cells (HUVECs). Methods: The experimental research methods were adopted. The third to the fifth passage of HUVECs in the logarithmic growth stage were used for the subsequent experiments. Three batches of cells were taken, with each batch of cells being divided into normal control group and negative pressure treatment alone group (both routinely cultured for 24 h), and 17-allylamino-17-demethoxy-geldanamycin (17-AAG) alone group and 17-AAG+negative pressure treatment group (both cultured with 17-AAG for 24 h). In addition, the intermittent negative pressure suction, with the negative pressure value of -5.33 kPa (suction for 30 s, pause for 10 s) was continuously applied for 8 h on cells in the two negative pressure treatment groups using an automatic three-dimensional cell gradient negative pressure loading device designed and developed by ourselves. After the treatment of the first batch of cells, the cell proliferation level was detected by cell counting kit 8 method at 0 (immediately), 24, 48, and 72 h of culture, with the number of samples being 6. After the treatment of the second batch of cells, the scratch experiment was performed. At 12 h after scratching, the cell migration was observed under an inverted phase contrast microscope and the cell migration rate was calculated, with the number of samples being 3. After the treatment of the third batch of cells, the tubule formation experiment was conducted. After 6 h of culture, the tubulogenesis was observed under an inverted phase contrast microscope and the total tubule length and the number of branch nodes of cells were calculated, with the number of samples being 3. The cells were taken and divided into normal control group, negative pressure treatment alone group, and 17-AAG+negative pressure treatment group. The cells were treated the same as in the previous corresponding group. After the treatment, Western blotting was used to detect the protein expressions of heat shock protein 90 (HSP90), caveolin 1, endothelial nitric oxide synthase (eNOS), and eNOS phosphorylation site 1177 in the cells, and the eNOS phosphorylation site 1177/eNOS ratio was calculated, with the number of samples being 3; co-immunoprecipitation (co-precipitating HSP90 and caveolin 1, caveolin 1 and eNOS) and Western blotting were used to detect the protein expressions of caveolin 1 and eNOS in the cells, with the number of samples being 3; the protein co-localization of HSP90 and caveolin 1 and that of caveolin 1 and eNOS in the cells was assessed by immunofluorescence double staining. The molecular docking prediction of caveolin 1 and eNOS was processed by HADDOCK 2.4 protein-protein docking program. Data were statistically analyzed with analysis of variance for factorial design, one-way analysis of variance, and least significant difference method. Results: Compared with that in normal control group, the cell proliferation level in 17-AAG alone group was significantly decreased at culture hour of 24, 48, and 72 after the treatment (P<0.01), while the cell proliferation level in negative pressure treatment alone group was significantly increased at culture hour of 24, 48, and 72 after the treatment (P<0.01). Compared with that in 17-AAG alone group, the cell proliferation level in 17-AAG+negative pressure treatment group was significantly increased at culture hour of 48 and 72 after the treatment (P<0.05 or P<0.01). Compared with that in negative pressure treatment alone group, the cell proliferation level in 17-AAG+negative pressure treatment group was significantly decreased at culture hour of 24, 48, and 72 after the treatment (P<0.01). At 12 h after scratching, compared with (39.9±2.7)% in normal control group, the cell migration rate in 17-AAG alone group was significantly decreased ((10.7±2.7)%, P<0.01), while the cell migration rate in negative pressure treatment alone group was significantly increased ((61.9±2.4)%, P<0.01). Compared with those in 17-AAG alone group, the cell migration rate in 17-AAG+negative pressure treatment group was significantly increased ((37.7±3.7)%, P<0.01). Compared with that in negative pressure treatment alone group, the cell migration rate in 17-AAG+negative pressure treatment group was significantly decreased (P<0.01). At culture hour of 6 after the treatment, compared with those in normal control group, the total length of the tube formed by the cells in 17-AAG alone group was significantly shortened (P<0.05) and the number of branch nodes was significantly reduced (P<0.05), while the total length of the tube formed by the cells in negative pressure treatment alone group was significantly prolonged (P<0.01) and the number of branch nodes was dramatically increased (P<0.01). Compared with that in 17-AAG alone group, the number of branch nodes of the tube formed by the cells was significantly increased in 17-AAG+negative pressure treatment group (P<0.05). Compared with those in negative pressure treatment alone group, the total length of the tube formed by the cells in 17-AAG+negative pressure treatment group was significantly shortened (P<0.01) and the number of branch nodes was significantly reduced (P<0.01). Western blotting detection showed that after treatment, the overall comparison of eNOS and caveolin 1 protein expressions among the three groups of cells showed no statistically significant differences (P>0.05). The expression of HSP90 protein and the eNOS phosphorylation site 1177/eNOS ratio in the cells of negative pressure treatment alone group were significantly increased (P<0.01) compared with those in normal control group. Compared with those in negative pressure treatment alone group, the HSP90 protein expression and the eNOS phosphorylation site 1177/eNOS ratio in the cells of 17-AAG+negative pressure treatment group were significantly decreased (P<0.01). Co-immunoprecipitation and Western blotting detection after the treatment showed that compared with those in normal control group, the expression of caveolin 1 protein in the cells of negative pressure treatment alone group was significantly increased (P<0.01), while the protein expression of eNOS was significantly decreased (P<0.05). Compared with those in negative pressure treatment alone group, the expression of caveolin 1 protein in the cells of 17-AAG+negative pressure treatment group was significantly decreased (P<0.01), while the protein expression of eNOS was significantly increased (P<0.01). After the treatment, compared with those in normal control group, the co-localization of HSP90 and caveolin 1 protein in the cells of negative pressure treatment alone group was significantly increased, while the co-localization of caveolin 1 and eNOS protein was significantly decreased. Compared with those in negative pressure treatment alone group, the co-localization of HSP90 and caveolin 1 protein in the cells of 17-AAG+negative pressure treatment group was significantly decreased, while the co-localization of caveolin 1 and eNOS protein was significantly increased. Molecular docking prediction suggested that caveolin 1 interacted strongly with eNOS and inhibited the 1177 site phosphorylation of eNOS. Conclusions: The negative pressure microenvironment may inhibit the binding of caveolin 1 to eNOS by promoting the binding of HSP90 to caveolin 1 in HUVECs, so as to relieve the inhibition of 1177 site phosphorylation of eNOS by caveolin 1, thereby promoting the proliferation, migration, and tubulogenesis of HUVECs, and ultimately promoting the neogenesis of HUVECs.
Caveolin 1/metabolism* ; Cells, Cultured ; HSP90 Heat-Shock Proteins/metabolism* ; Human Umbilical Vein Endothelial Cells/metabolism* ; Humans ; Molecular Docking Simulation ; Phosphorylation

OBJECTIVE: To investigate the effect of PPP2R5C to the activity of Molt-4 cells in childhood acute T lymphocytic leukemia and its mechanism. METHODS: The small interfering RNA (siRNA) technology targeting PPP2R5C gene was used to down-regulate the expression of PPP2R5C in Molt-4 cells. At the same time, a blank control group, a negative control group and a 17-DMAG group were set up. The cells in the negative control group were transfected with siRNA-NC, the cells in 17-DMAG group were treated with the HSP90 inhibitor 17-DMAG at a final concentration of 6.4 μmol/L for 48 h. Real-time fluorescent quantitative PCR (RT-qPCR) and Western blot were used to detect transfection efficiency; CCK-8 method was used to detect the proliferation activity of the cells in each group, EdU was used to detect the proliferation level of the cells in each group, flow cytometry was used to detect the cell cycle distribution ratio of the cells in each group, Annexin V-FITC/PI staining was used to detect the apoptosis of the cell, RT-qPCR and Western blot were used to detect the expression changes of heat shock protein 90 (HSP90) and glucocorticoid receptor (GR) of the cells in each group. RESULTS: After Molt-4 cells were transfected with siRNA-PPP2R5C, the expression of PPP2R5C mRNA and protein in the cells were down-regulated significantly compared with those in the blank control group and the si-NC group (P<0.05); compared with cells in the blank control group and the si-NC group, the proliferation activity of the cells in the siRNA-PPP2R5C group and the 17-DMAG group significantly decreased (P<0.05), and the rate of EdU positive cells was significantly reduced (P<0.05); the proportion of the cells in G1 phase decreased while the proportion of the cells in G₂ phase increased (P<0.05), the apoptosis rate of the cells also increased significantly (P<0.05); in addition, the expression of PPP2R5C mRNA and protein of the cells in siRNA-PPP2R5C group was significantly down-regulated compared with those in the blank control group and si-NC group (P<0.05). The expressions of PPP2R5C mRNA and protein in the 17-DMAG group were also significantly down-regulated compared with those in the blank control group and si-NC group (P<0.05). CONCLUSION Down-regulation of PPP2R5C gene expression can inhibit Molt-4 cell activity in childhood acute T lymphocytic leukemia, block the cells in G₂ phase, and promote cell apoptosis, the mechanism may be related to the inhibition of HSP90-GR signaling pathway.
Apoptosis ; Cell Line, Tumor ; Cell Proliferation ; Cell Survival ; Child ; HSP90 Heat-Shock Proteins ; Humans ; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma ; RNA, Small Interfering ; Receptors, Glucocorticoid

OBJECTIVE: To investigate the expression of HSP90 in bone marrow samples of multiple myeloma (MM) patients and explore its clinical significance. METHODS: Maxvision immunohistochemistry technique was used to detect the protein expression level of HSP90 76 MM patients and 29 normal healthy donors. The clinical characteristics of the patients were collected, and the correlation between the HSP90 expression and the clinical characteristics was analyzed. RESULTS: The count of MM patients with positive HSP90 protein was significantly higher than that of normal healthy donor, and there were no significant correlation between HSP90 expression and age, sex, hemoglobin (Hb), creatinine (CREA), blood calcium, lactate dehydrogenase (LDH), bone marrow plasma cell proportion and MM subtypes (P>0.05), but HSP90 expression was correlated with β CONCLUSION HSP90 protein was over-expressed in MM patients, and was correlated with β
Bone Marrow ; HSP90 Heat-Shock Proteins ; Humans ; Multiple Myeloma ; Prognosis ; beta 2-Microglobulin

This study was aimed to investigate the regulatory mechanism of heat shock protein 90 (Hsp90) on transcription factor EB (TFEB) during autophagy in liver cancer cells. Human hepatocellular carcinoma cell line HepG2 was treated with Hsp90 N- and C-terminal inhibitors (STA9090 and Novobiocin), respectively. Western blot and RT-PCR were used to detect the expression levels of TFEB and autophagy-related proteins. Chromatin immunoprecipitation (ChIP) assay was used to observe the ability of Hsp90α binding to the TFEB proximal promoter region. The double-luciferase gene reporter experiment was used to determine the activity of TFEB promoter. The results showed that hypoxia induced up-regulation of TFEB protein and mRNA expression levels in the HepG2 cells. The protein expression levels of TFEB, LC3 and P62 were down-regulated significantly by either STA9090 or Novobiocin, under both normoxic and hypoxic conditions. Transfection of Hsp90α-overexpressing plasmids up-regulated TFEB protein levels in either wild-type or Hsp90α knockout HepG2 cells. Hsp90 bound to the TFEB proximal promoter region and was involved in regulating TFEB transcriptional process. Whereas both STA9090 and Novobiocin inhibited Hsp90 to bind to the TFEB proximal promoter region, and decreased the activity of TFEB promoter. These results suggest that Hsp90 promotes TFEB transcription in human hepatocellular carcinoma cells by binding to the proximal promoter region, thereby up-regulating the expression levels of autophagy-related proteins.
Autophagy ; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors ; metabolism ; Carcinoma, Hepatocellular ; metabolism ; pathology ; HSP90 Heat-Shock Proteins ; metabolism ; Hep G2 Cells ; Humans ; Liver Neoplasms ; metabolism ; pathology ; Promoter Regions, Genetic

PURPOSE: The mechanisms underlying repolarization abnormalities during pregnancy are not fully understood. Although maternal serotonin (5-hydroxytryptamine, 5-HT) production is an important determinant for normal fetal development in mice, its role in mothers remains unclear. We evaluated the role of serotonin in ventricular repolarization in mice hearts via 5Htr3 receptor (Htr3a) and investigated the mechanism of QT-prolongation during pregnancy. MATERIALS AND METHODS: We measured current amplitudes and the expression levels of voltage-gated K⁺ (Kv) channels in freshly-isolated left ventricular myocytes from wild-type non-pregnant (WT-NP), late-pregnant (WT-LP), and non-pregnant Htr3a homozygous knockout mice (Htr3a(−/−)-NP). RESULTS: During pregnancy, serotonin and tryptophan hydroxylase 1, a rate-limiting enzyme for the synthesis of serotonin, were markedly increased in hearts and serum. Serotonin increased Kv current densities concomitant with the shortening of the QT interval in WT-NP mice, but not in WT-LP and Htr3a(−/−)-NP mice. Ondansetron, an Htr3 antagonist, decreased Kv currents in WT-LP mice, but not in WT-NP mice. Kv4.3 directly interacted with Htr3a, and this binding was facilitated by serotonin. Serotonin increased the trafficking of Kv4.3 channels to the cellular membrane in WT-NP. CONCLUSION: Serotonin increases repolarizing currents by augmenting Kv currents. Elevated serotonin levels during pregnancy counterbalance pregnancy-related QT prolongation by facilitating Htr3-mediated Kv currents.
*Action Potentials/drug effects ; Animals ; Cell Membrane/drug effects/metabolism ; Disease Models, Animal ; Electrocardiography ; Female ; HSC70 Heat-Shock Proteins/metabolism ; HSP90 Heat-Shock Proteins/metabolism ; Heart Ventricles/drug effects/*metabolism ; Mice, Inbred C57BL ; Mice, Knockout ; Myocytes, Cardiac/drug effects/metabolism ; Potassium Channels/metabolism ; Pregnancy ; Rabbits ; Rats, Sprague-Dawley ; Receptors, Serotonin, 5-HT3/metabolism ; Serotonin/*metabolism ; Serotonin 5-HT3 Receptor Agonists/pharmacology

Protein palmitoylation, one of post-translation modifications, refers to the addition of saturated 16-carbon palmitic acid to cysteine residues via the thioester bond. It plays key roles in various functional activities, such as the interaction, stability and location of proteins. Heat shock protein 90 (Hsp90), an important molecular chaperone, has been reported to be involved in sperm capacitation. However, it remains unclear whether protein palmitoylation exists in sperm and whether Hsp90 in sperm is palmitoylated under different physiological conditions. In this study, we examined whether the protein palmitoylation is present in mouse cauda epididymis sperm using acyl-biotin exchange method, predicted the potential palmitoylated sites of Hsp90 by the software CSS-Palm 4.0 and detected the palmitoylated Hsp90 in the mouse sperm from caput epididymis and cauda epididymis by immunoprecipitation. We found that some proteins, approximately 50, 65, 72, 85 and 130 kDa, were palmitoylated in mouse cauda epididymis sperm. Five sites in two Hsp90 isoforms were predicted to be palmitoylated. The results also showed that Hsp90 in mouse sperm was palmitoylated and its palmitoylation level was involved in different physiological conditions: the palmitoylation level of cauda epididymis sperm was higher than that of caput epididymis sperm; and the palmitoylation level after capacitation was much higher than that before capacitation. In conclusion, this study reveals that protein palmitoylation is present in mouse sperm and the palmitoylated Hsp90 is associated with different physiological conditions in sperm.
Animals ; Epididymis ; HSP90 Heat-Shock Proteins ; metabolism ; Lipoylation ; Male ; Mice ; Palmitic Acid ; chemistry ; Sperm Capacitation ; Spermatozoa ; metabolism

To determine heat-shock protein (Hsp)90 expression is connected with cellular apoptotic response to heat stress and its mechanism, chicken (Gallus gallus) primary myocardial cells were treated with the Hsp90 promoter, aspirin, and its inhibitor, geldanamycin (GA), before heat stress. Cellular viability, heat-stressed apoptosis and reactive oxygen species level under different treatments were measured, and the expression of key proteins of the signaling pathway related to Hsp90 and their colocalization with Hsp90 were detected. The results showed that aspirin treatment increased the expression of protein kinase B (Akt), the signal transducer and activator of transcription (STAT)-3 and p-IKKα/β and the colocalization of Akt and STAT-3 with Hsp90 during heat stress, which was accompanied by improved viability and low apoptosis. GA significantly inhibited Akt expression and p-IKKα/β level, but not STAT-3 quantity, while the colocalization of Akt and STAT-3 with Hsp90 was weakened, followed by lower cell viability and higher apoptosis. Aspirin after GA treatment partially improved the stress response and apoptosis rate of tested cells caused by the recovery of Akt expression and colocalization, rather than the level of STAT-3 (including its co-localization with Hsp90) and p-IKKα/β. Therefore, Hsp90 expression has a positive effect on cellular capacity to resist heat-stressed injury and apoptosis. Moreover, inhibition of Hsp90 before stress partially attenuated its positive effects.
Apoptosis* ; Aspirin ; Cell Survival ; Chickens* ; Heat Stress Disorders ; Heat-Shock Proteins* ; Hot Temperature* ; HSP90 Heat-Shock Proteins ; In Vitro Techniques* ; Proto-Oncogene Proteins c-akt ; Reactive Oxygen Species ; Transducers