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OBJECTIVES@#The pathogenesis of androgenetic alopecia (AGA) is related to the level of androgen and its metabolic pathways. The binding of androgen and androgen receptor (AR) depends on the assistance of heat shock protein 27 (HSP27). HSP27 combined with microRNAs (miR)-1 can regulate AR levels. However, it is not clear whether HSP27 and miR-1 jointly participate in the pathogenesis of AGA. This study aims to investigate the role of AR up-regulation in the pathogenesis of AGA and underlying mechanisms.@*METHODS@#A total of 46 male AGA patients (AGA group), who admitted to the First Affiliated Hospital of Guangzhou Medical University from September 2019 to February 2020, and 52 healthy controls admitted to the same period were enrolled in this study. Serum levels of dihydrotestosterone (DHT) and HSP27 in patients and healthy controls were measured by ELISA. Western blotting was used to detect the protein expression of HSP27 and AR in scalp tissues of patients and the healthy controls. The levels of HSP27, AR, and miR-1 were analyzed using real-time PCR. Human dermal papilla cells were transfected with HSP27 siRNA to inhibit the expression of HSP27. MiR-1 and miR-1 inhibitors were transfected simultaneously or separately into cells and then the changes in AR protein expression were detected.@*RESULTS@#The levels of DHT and HSP27 in the AGA group were (361.4±187.7) pg/mL and (89.4±21.8) ng/mL, respectively, which were higher than those in the control group [(281.8±176.6) pg/mL and (41.2±13.7) ng/mL, both P<0.05]. However, there was no significant difference in serum HSP27 and AR levels among AGA patients with different degrees of hair loss (P>0.05). Correlation analysis showed that there was a positive correlation between HSP27 level and DHT level in the AGA patients (P<0.05). The level of HSP27 mRNA in scalp tissue was negatively correlated with that of miR-1 mRNA (P<0.05). Compared with the control group, the levels of HSP27 protein, AR protein, HSP27 mRNA, and AR mRNA in scalp tissues of AGA group were significantly increased (P<0.05). The up-regulation of HSP27 in scalp tissues of AGA patients was closely related to the increased levels of AR. However, the level of miR-1 in scalp tissues of AGA patients was significantly down-regulated, contrary to the expression of AR (P<0.05). Further in cell studies showed that inhibition of HSP27 or miR-1 expression in human dermal papilla cells could inhibit the expression of AR, and inhibition of both HSP27 and miR-1 expression was found to have an accumulative effect on AR, with statistically significant differences (all P<0.05).@*CONCLUSIONS@#HSP27 could combine with miR-1 to up-regulate AR levels, which is closely related to the development of AGA.
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Humans , Male , Alopecia/pathology , HSP27 Heat-Shock Proteins/metabolism , MicroRNAs/genetics , RNA, Messenger , Receptors, Androgen/metabolism , Up-RegulationABSTRACT
Heat shock proteins (HSP) are highly conserved proteins that protect cells and enhance the body's resistance to stress. Heat shock protein 27 (HSP27) also known as heat shock protein beta-1 (HSPB1) is a small molecular weight HSP that in humans is encoded by the HSPB1 gene. HSP27 exerts its effect mainly in the form of phosphorylation activity, and has a variety of important biological functions, such as chaperone activity, thermotolerance, anti-oxidation and inhibition of apoptosis. HSP27 was found to be highly expressed in a variety of intestinal diseases. This article reviews the structure, function, mechanism of action of HSP27 and the relationship between HSP27 and intestinal diseases, and explores the clinical value and application prospect of HSP27 in intestinal diseases.
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Objective:To detect the expressions of ovarian function-related proteins in the ovarian follicles in different development stages,and to explore their roles and significances in the regulation of follicular development and ovarian function. Methods:The ovarian tissue containing primordial,primary,secondary follicles,mature follicles, atretic follicles and corpus albicans of the woman in the childbearing age was selected. Immunohisto chemical analysis was used to detect the expressions of Glyoxal enzyme I (glyoxalase I),ubiquitin carboxy-terminal hydrolase L1 (UCH-L1),heat shock protein 27 (HSP27),serum amyloid P (SAP)proteins in the ovarian follicles in different stages.The expression intensities of these proteins were compared.Results:The expression intensities of Glyoxalase I and UCH-L1 in the granulosa cells and theca cells of secondary follicles and marure follicles were strong,which were higher than those in the cytoplasm of primordial and primary follicles.The expression intensities of HSP27 in the cytoplasm of primordial and primary follicles were strong,which were higher than those in the granulosa cells and theca cells of secondary follicles and marure follicles.The expression intensities of Glyoxalase I and HSP27 in the atretic follicles were strong,which were higher than that in the growth follicles. The expressions of SAP were positive in the primordial,primary follicles,secondary and mature follicles and the expression intensities were not different.The expressions of four proteins in the corpus albicans did not express. Conclusion:The high expression of UCH-L1 and low expression of HSP27 are associated with the mature and development of follicles;the high expressions of Glyoxalase I and HSP27 are associated with the follicular atresia and ovarian failure.
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Introduction: It is possible that immunological factors, including the heat shock protein family, are involved in the development of the different forms of dementia. We aimed to compare the levels of serum HSP27 in patients with Alzheimer’s disease and vascular dementia. Materials and Methods: Thirty patients with grade 2 Alzheimer’s disease, 30 patients with grade 2 vascular dementia and 30 normal subjects as a control group were recruited during November 2011 to November 2013. Diagnoses were based on DSM-IV-TR criteria. MMSE was conducted on all patients for assessing the severity of disease. Biochemical parameters, including HSP27 were measured in all subjects. Demographic characteristics were collected for all subjects. Results: There were no statistically significant differences in age, gender and the levels of HSP27 between males and females in all groups. However there was a significant association between HSP27 with the severity and duration of dementia in patients groups. HSP27 levels were lower in the vascular dementia compared to those with Alzheimer’s dementia, but were higher than for controls. Conclusion: HSP27 antibody titers were positively related to the severity and duration of both Alzheimer’s and vascular dementia and may be indicative of the role of this protein in the pathology of dementia.
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AIM: To detect whether N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) inhibits epithelial-mes-enchymal transition in A549 cells induced by TGF-β1 through suppressing the expression of heat shock protein 27 (HSP27) and zinc finger proteins Snail (including SNAI1and SNAI2) which ultimately inhibited the deposition of type I and type III collagens.METHODS:The colocalizations of HSP27 and SNAI1/SNAI2 respectively on A549 alveolar epi-thelial cells induced by TGF-β1 were measured by confocal microscopy .The expression of HSP27, SNAI1 and SNAI2 at mRNA level was detected by real-time PCR.Western blotting analysis was used to detect the expression of HSP 27, SNAI1 and SNAI2 on epithelial-mesenchymal transition in A549 cells induced by TGF-β1 and also the deposition of type I and type III collagens in A549 cells transfected with HSP27shRNA prior to TGF-β1 stimulation.RESULTS: Compared with control group, TGF-β1 increased the expression of HSP27, SNAI1, SNAI2, type I and type III collagen, which decreased significantly followed by Ac-SDKP intervention.The expression of SNAI1, type I and type III collagen decreased signifi-cantly after transfected with HSP27shRNA in A549 cells, which had the similar effect on Ac-SDKP intervention.CON-CLUSION:Ac-SDKP inhibits the transition of cultured A 549 cells to myofibroblasts and attenuates collagen synthesis by suppressing the expression of HSP 27 and zinc finger proteins SNAI 1 and SNAI2.
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AIM: To construct the prokaryotic expression system containing protein transduction domain (PTD) with heat shock protein 27 (HSP27) in order to prepare and purify the recombinant protein , and to verify whether the recombinant protein PTD-HSP27 has the ability to penetrate the human lens epithelial cell ( HLEC) membrane and the rabbit cornea.METHODS:The plasmid pKYB-PTD-HSPB1-6His was constructed by the technique of overlap extension PCR.The plasmid was transformed and PTD-HSP27 was purified through nickel affinity chromatography column and identi-fied by Western blotting.PTD-HSP27-6His was labeled with the fluorescein isothiocyanate (FITC).The penetrating ability of PTD-HSP27 into HLECs and rabbit cornea was tested .RESULTS:The recombinant PTD-HSP27 plasmid was success-fully cloned and effectively expressed .The correctness of the recombinant protein PTD-HSP27 was demonstrated .Fluores-cence microscopic examination showed that PTD-HSP27-FITC was internalized by HLECs .Fluorescent labeled PTD-HSP27 was then observed in the rabbit aqueous humor .CONCLUSION:The recombined gene PTD-HSPB1 was constructed by o-verlap extension PCR technique and the PTD-HSP27 fusion protein was prepared and purified by nickel affinity chromatog-raphy column.Using the technique of PTD-fusion protein, HSP27 was transduced into HLECs and passed through the cor-nea .
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Objective To investigate the clinical significance of heat shock protein 27(HSP-27) and glypican-3(GPC-3) in diag-nosing primary hepatic cancer (PHC) and the clinicopathologic characteristics by detecting their expression in PHC .Methods Im-munohistochemistry was used to detect the expression of HSP-27 and GPC-3 in 32 cases of PHC tissue ,30 cases of live cirrhosis tissue ,25 cases of benign liver occupying tissue and 31 cases of hepatitis tissue .The relationship between their expression and the clinicopathologic features of PHC was analyzed .Results HSP-27 and GPC-3 were highly expressed in the PHC tissues ,the differ-ence had statistical significance compared with their expression levels in the liver cirrhosis tissues ,liver benign neoplasm tissues and hepatitis tissues(P<0 .05) .The expression of HSP-27 in the PHC tissues was correlated with the tumor pathological grade and the TNM stage ,while the expression of GPC-3 was not correlated with the tumor pathological grade and the TNM stage .Conclusion The high expression of HSP-27 and GPC-3 in the PHC tissue is closely related with the tumorigenesis ,progress ,metastasis of PHC ,which may become new pathological diagnosis markers of PHC .
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Objective To explore the mechanism action of Shoutai Pill in the embryo from the molecular level. Methods The model of normal pregnancy was established with the model of recurrent abortion CBA/J ×DBA/2. The recurrent abortion model CBA/J×DBA/2 in pregnant mice were randomly divided into model group, high-, medium-, low-dose group of Shoutai Pill. From the first day of gestation, mice were given medicine by gavage for 14 d, and then sacrificed. Immunohistochemistry was used to detect differences in protein HSP27,α-enolase, transferrin, annexin A2 protein expression. Results Compared with normal group, decidual HSP27 and α-enolase expression of model group increased significantly, the expression of transferrin and annexin A2 was significantly decreased, with significant differences (P0.05). Conclusion Through the protein expression, Shoutai Pill achieves the maintenance of pregnancy, reducing the rate of embryo resorption, which may be one of the mechanisms of Shoutai Pill preventing miscarriage effect.
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Objective To detect the expressions of nm23-H1 and heat shock protein 27 (HSP27) and their clinical significance on development and metastasis in non-small cell lung carcinoma (NSCLC).Methods 75 tumor tissues from patients with NSCLC were included as experimental group and 28 pulmonary benign lesion tissues were as control group.The expressions of nm23-H1 and HSP27 in patients with different clinical and pathological characters were detected by immunohistochemistry.Results nm23-H1 and HSP27 were mainly expressed in cytoplasm,the positive rates of nm23-H1 and HSP27 were significantly higher in the experimental group than that in control group [41.3 ％ (31/75) vs 7.1％ (2/28),x2 =10.946,P =0.001,80.0 ％ (60/75) vs 46.4 ％ (13/28),x2 =11.131,P =0.001].Compared with control group,the positive rate of HSP27 was correlated with the degree of tumor differentiation (x2 =4.191,P =0.041).nm23-H1 was related with HSP27 in lung cancer (r =0.284,P =0.013).Conclusion nm23-H1 and HSP27 are related to the occurrence and development of NSCLC.The joint detection of nm23-H1 and HSP27 should be helpful to the diagnosis and judge the biological behavior of NSCLC.
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Objective To investigate the expression of heat shock protein 27(HSP27)in esophageal squamous carcinoma,mucosa adjacent to carcinoma and normal esophageal mucosa,and its relationship with the carcinogenesis of esophageal carcinoma.Methods The expression of HSP27 was observed in 86 specimens from esophageal squamous carcinoma,86 from mucosa adjacent to carcinoma and 75 from normal esophageal mucosa by immunohistochemistry.Results The expression of HSP27 in esophageal squamous carcinomas was higher than those in mucosa adjacent to carcinoma(P ＜ 0.05);the expression of HSP27 in mucosa adjacent to carcinoma was higher than those in normal esophageal mucosa(P ＜0.001).There was no significant difference in the expression of HSP27 in esophageal squamous carcinomas with different differentiation degree(P ＞ 0.05).Conclusion Expression of HSP27 was associated with the carcinogenesis of esophageal squamous carcinoma.
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Background Glaucoma is common blinding eye diseases characterized by chronic loss of retinal ganglion cells(RGCs).Currently glaucoma pathogenesis is not completely understood,heat shock protein 27 ( HSP27 )may be associated with the pathogenesis of glaucomatous optic neuropathy. Objective Through the establishment of a rat model of high intraocular pressure,detection of the expression of HSP27 antibody in serum and RGCs apoptosis to investigate the role of HSP27 in RGCs apoptosis. Methods Fifty-one clean Wistar rats were divided into high intraocular pressure group (34 rats)and sham operation group( 17 rats)using a random number table.An animal model of high intraocular pressure was established in the right eye by the application of bipolar underwater electrocoagulation on vein of sclera surface in the experimental group,and rats with conjunctiva incision only without electric coagulation were served as sham operation (control).The intraocular pressure of rats of the both groups including experimental and control rats was measured 1,2,4,6,8 weeks after operation and then the rats were sacrificed.1 ml serum was collected from these rats to determine the concentration of HSP27 antibody.The retinas of the rats were isolated and homogenated for the extraction and analysis of the retinal protein by Western blot.Apoptosis of RGCs were assayed by TUNEL.The use of the experimental animals followed the Regulations for the Administration of Affair Concerning Experimental Animals by Kunming Medical Collegc. Results Intraocular pressure was elevated significantly after modeling and remained a high value during the expcrimental duration,showing a significant difference among the different groups ( F =318.502,P＜0.01 ).However,no significant change in intraocular pressure before and after operation in the sham-operation group ( F =2.076,P ＞ 0.05 ).The serum concentration of HSP27 antibody was increased significantly overtime from 1,2,4,6 to 8 weeks after the surgery applied,with a significant difference among various time points( F =154.221,P＜0.01 ),but no obvious difference was seen in the shamoperation group( F =0.422,P＞0.05 ).Importantly,Apoptosis rate of RGCs in the experimental eyes was significant higher as the time prolong after intraocular elevated(x2=856.12,P＜0.05 ).The positive rate of RGCs apoptosis in the rats with high intraocular pressure group was elevated significantly compared to the rats in the sham operation group(P＜0.05). Conclusions High intraocular pressure induces the expressions of HSP27 in retina and the accumulation of HSP27 antibody in rats serum;the elevated HSP27 is associated with the increased cell death in RGCs.
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Objective To provide molecular genetic basis for oncobiological difference in left sided colon cancer and right sided colon cancer. Differentially expressed proteins in left sided colon cancer and right sided colon cancer were screened by proteomic technique. Methods Tissue samples including left sided colon cancer and right sided colon cancer were collected and preserved in the -80℃ refrigerator. In the first part of our experiment, protein was separated by 2-dimensional gel electrophoresis (2-DE) and the images of the gels were acquired by the scanner and then analyzed to find the differentially expression protein-spots in different groups. The peptide mass fingerprintings (PMF) was acquired by matrix assisted laser desorptiorn/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and the proteins were identified by data searching in the Mascotdatabase. Differentially expressed proteins were assayed by RT-PCR, Western blot, and immunohistochemical method. Results Altogether 55 differentially expressed protein spots were screened and 21 spots of them were identified. Compared with the right sided colon cancer, 14 proteins were up-regulated and 7 proteins down-regulated including HSP27 in the left sided colon cancer. HSP27 expressed higher in the right sided colon cancer than in the left sided colon cancer.Conclusion There are differentially expressed proteins in left sided colon cancer and right sided colon cancer, especially difference in HSP27 expression at mRNA and protein level, which may be molecular genetic basis for oncobiological difference in left sided colon cancer and right sided colon cancer.
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Heat shock protein 27 is a small kind of protein which is produced under stress. HSP 27 is highly conservative, and plays an important role in ischemia-reperfusion injury. With the development of organ transplantation technique,the transplantation of heart,liver,kidney becomes more and more popular, the ischemia-reperfusion injury is a significant part of the management of these procedures. The endogenic research against the injury becomes more vital. This article is the first review of the relationship between heat shock protein 27 and ischemiareperfusion injury.
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Objective To investigate the cardiac protection of Hsp27 against endotoxic cardiac depression mediated by activation of PI3K/Akt pathway and the suppression of NFκB-mediated inflammatory response in mice. Method (1) Transgenic mice with cardiac specific overexpression of Hsp27 (Hsp27 Tg) and wild littermate controls (WT) were given 10 mg/kg LPS injected intraperitoneally to induce endotoxemia, (2) The cardiac function measurement in mice was performed by using echocardiography 6 hours after LPS treatment (n = 6), (3) The activity of PBK/Akt pathway was evaluated by Western blot for [hosphor-Akt (p-Akt) and phosphor-Gsk-3β (p-Gsk-3β) one hour after LPS administration ( n = 4)], (4) Activity of inflammatory response was evaluated by protein degradation of IκBα (n = 4), (5) The apoptosis of myocardial cells was determined by TUNEL assay on the paraffin section of cardiac tissue 24 hours after LPS exposure (n = 4). Results (1) Hsp27 attenuated cardiac dysfunction significantly following LPS treatment. Compared with the primary value, LPS induced the depression of cardiac function both in WT rats and Hsp27Tg rats. However, the cardiac dysfunction was attenuated significantly in Hsp27Tg rats compared with that in WT rats ( P < 0.01 or 0.05) . (2) Hsp27 attenuated IκBα degradation after LPS administration. Compared with the primary value, LPS led to LκBα degradation by (72.92 + 9.20) % in WT rats and by (41.43 + 24.10) % in Hsp27Tg rats. The overexpression of Hsp27 lessened the IκBα degradation significantly (P < 0.05). The similar results were obtained in rat myocardial cell culture of experiments. (3) Hsp27 enhanced the activation of PI3K/Akt signaling following LPS exposure. One hour after LPS administration, the relative levels of p-Akt and p-GSK-30 were (3.11 + 0.83) and (3.19 + 1.04), respectively in WT rats, and (5.13 + 0.73) and (5.71 + 1.20) in Hsp27Tg rats, respectively. Compared with WT rats, the levels of p-Akt and p-GSK-3β were significantly higher in Hsp27Tg rats (P < 0.05). (4) The Hsp27 lessened LPS-induced the apopto-sis of myocardial cells. Twenty-four hours after LPS treatment, the percentages of myocardial cell apoptosis were (6.46+ 1.74)% in WT rats and (2.88 + 0.91)% in Hsp27Tg rats. Compared with WT rats, LPS-induced apoptosis in myocardial cells was significantly decreased in Hsp27Tg rats (P < 0.01). Conclusions The overexpression ofHsp27 attenuates cardiac dysfunction significantly during endotoxemia, and the mechanisms may be attributed to the activation of PDK/Akt signaling pathway.
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Blotting, Western , Fibroblasts , Heat-Shock Proteins , Heat-Shock Response , HSP27 Heat-Shock Proteins , Immunohistochemistry , Osseointegration , Osteoblasts , Primary Cell Culture , Proteins , Staphylococcal Protein AABSTRACT
BACKGROUND: Heat shock protein 27 (HSP27) is induced by heat shock and other pathophysiologic stresses, including neoplastic transformation. We examined the relationship between the HSP27 expression and the clinical and histologic parameters to elucidate the biologic and prognostic significance of HSP27 in renal cell carcinomas (RCCs). Its regulation of apoptosis in RCC development was also observed. METHODS: We performed immunohistochemical studies for HSP27, caspase 3 and TUNEL on paraffin-embedded tissue microarray specimens from 48 RCCs. RESULTS: There was a tendency to higher expression of HSP27 in the RCC than in normal renal tubular cells. Of the 48 RCCs, the HSP27 expression was positive in 38 cases. An inverse relationship was found between the Fuhrman nuclear grade and HSP27 expression, but this was without statistical significance (r=-0.218, p=0.093). No relationship between the HSP27 expression and the other parameters was observed. Also, no statistically significant difference was observed between apoptosis and the HSP27 expression more (p=0.951). CONCLUSIONS: Although HSP27 expression was increased in RCC than in normal renal tubular cell the HSP27 expression may not be a powerful and statistically significant prognostic indicator in patients with RCC.
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Humans , Apoptosis , Carcinoma, Renal Cell , Caspase 3 , Heat-Shock Proteins , Hot Temperature , HSP27 Heat-Shock Proteins , In Situ Nick-End Labeling , ShockABSTRACT
The effects of sodium salicylate on the expression of heat shock protein 27 (HSP27)during oxidative stress in tissue-cultured human lens epithelial cells were investigated. Cultured human lens epithelial cells (HLB-3) were divided into 3 groups: control group (group A), oxidation injury group (group B) and sodium salicylate group (group C). Apoptosis of human lens epithelial cells cultured in vitro was induced in the presence of 150 μmol/L H2O2. Cells viability and the expression of HSP27 were analyzed. Viability of the cells was measured by methyl thiazole tetrazolium (MTT)chromatometry. The expression of HSP27 in HLB-3 cells was detected by using immunohistochemistry and image analysis system. Sodium salicylate could induce the expression of HSP27, and the cells viability in group C was significantly higher than in group B (0.2667±0.01414 vs 0.2150±0.01080, P=0.012＜0.05). The average gray value of HSP27 in group B was less than that in group C (P=0.000＜0.05). The increased expression of HSP27 by sodium salicylate might play an important role in the protection of hydrogen peroxide-induced injury of human lens epithelial cells,suggesting that sodium salicylate could suppress, at least in part, the apoptosis of human lens epithelial cells.
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Cadmium , Cell Line , Cell Line, Transformed , Cell Survival , Chromium , Heat-Shock Proteins , HSP27 Heat-Shock Proteins , Ions , Molecular Chaperones , Osteoblasts , Osteogenesis , TitaniumABSTRACT
Objective:Increased reactive oxygen species (ROS) formation and by which in turn promotes cardiomyocytes apoptosis is associated with the pathogenesis and progression of various cardiac diseases. Small heat shock protein 27(Hsp27) could protect different cells from oxidative damage. By using tissue nonspecific overexpression Hsp 27 transgenic model, other investigators demonstrated that Hsp27 suppressed successfully kainate-induced seizures and hippocampal cell death in intact transgenic mice, and attenuated mimic ischemia/reperfusion injury in Langendorff-perfused isolated mice heart. As there are complicated and long distance neuro-humoral regulation associated with the development of cardiac diseases, it is better to choose a cardiac-specific overexpression transgenic model to study the effects of Hsp27 in hearts in vivo.Methods:A cDNA encoding human Hsp27 was subcloned into pBSII-SK+ containing the ?-myosin heavy chain (?-MHC) promoter (generously provided by Dr. J. Robbins, Children’s Hospital of Cincinnati, Ohio). BamHI-digested linear transgene consistent with the ?-MHC promoter, Hsp27 cDNA, and poly (A) of human growth hormone (hGH) was microinjected into the fertilized eggs from CBA/BL6 mice. Mice containing the transgene were identified by polymerase chain reaction. Founders revealed by this screening were used to establish independent transgenic lines. Following successful transmission, a range of tissues including heart, lung, liver, brain, skeleton muscle, spleen and kidney was screened by Western blot to confirm the cardiac specific expression of the transgene. Results and Discussion:Transgenic mice expressed Hsp27 under the control of a-MHC promoter. Cardiac tissues from independent TG line expressed abundant Hsp27, and as expected, Hsp27 expressed in cardiac tissues only, whereas none in liver, spleen, lung, kidney, brain and skeleton muscle. Surprisingly, Hsp25, the endogenous isoform of Hsp27 in murine, was downregulated by Hsp27 overexpression (data not shown), which is in contrast to the result of Hollander’s [1]. It needs to determine in future whether Hsp27 expression profile in heart could exert any effect on the regulation of Hsp25.Conclusion: The TG mice overexpression human Hsp27 specifically in the heart by using ?MHC- promotor were created. All TG mice expressed Hsp27 abundantly and cardiac-specifically. To our knowledge, it is the first report of creation of transgenic mice which overexpressing Hsp27 cardiac specifically. This current model suggests that the Hsp27 cardiac-specific over-expression of transgenic mouse remains a robust genetic tool for dissecting molecular and genetic events involving Hsp27, which could be a therapeutic target in heart failure.
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@#ObjectiveTo investigate the mechanism and the protective effect of heat shock protein 27 (HSP27) on rat cardiomyocytes when ischemic preconditioning performed.MethodsCultured rat cardiomyocytes were divided into four groups: control group, ischemic group,ischemic preconditioning group and cyclohexamide group. Cell viabilities were analyzed by MTT. The apoptosis was evaluated with DNA ladder and flow cytometry Annexin V Flous staining. Western Blot was used to determine the expression of HSP27 and caspase-3 in cardiomyocytes.ResultsIschemic preconditioning could improve cell viability. The apoptosis ratio in ischemic preconditioning group was significantly less than that in ischemic group. These were accompanied by an increase in the expression of HSP27 and a decrease in caspase-3. The expression of the increased HSP27 and the protective effect induced by ischemic preconditioning were completely abolished by the presence of cycloheximide, a translation inhibitor.ConclusionThe expression of HSP27 induced by ischemic preconditioning plays an important role in protecting cardiomyocytes, and the mechanism is possibly related to the inhibition of cell apoptosis.