ABSTRACT
Objective@#To study the effect of low concentrations of sodium fluoride on the osteogenic/odontogenic differentiation of human dental pulp cells (hDPCs) in vitro.@*Methods@#This study was reviewed and approved by the Ethics Committee. hDPCs were cultured using a modified tissue explant technique in vitro. The effects of different concentrations of sodium fluoride on the proliferation of hDPCs were measured by methylthiazol tetrazolium (MTT) assay. Appropriate concentrations were added to the osteogenic/odontogenic differentiation induction medium, and the cells were induced in vitro. Alizarin red S staining was used to detect the osteoblastic/odontogenic differentiation ability of the cells, and the mRNA expression of the key differentiation factors was detected by RT-qPCR. Moreover, the expression of key molecules of endoplasmic reticulum stress (ERS) was detected by RT-qPCR and Western blot. The data were analyzed with the SPSS 18.0 software package.@*Results@#Low concentration of NaF (0.1 mmol/L) could stimulate cell proliferation in vitro, while a high concentration (5-10 mmol/L) could inhibit cell proliferation (P<0.05). According to the literature and the experimental data, 0.1 mmol/L NaF was selected as the following experimental concentration. The levels of alizarin red S staining were increased after NaF induction of mixed osteogenic/odontogenic differentiation in vitro. The mRNA expression levels of key molecules for osteogenic/odontogenic differentiation, dentin sialophosphoprotein (DSPP), bone sialoprotein (BSP) and osteocalcin (OCN), were increased (P<0.05). The mRNA levels of ERS markers (splicing x-box binding protein-1 (sXBP1), glucose-regulated protein 78 (GRP78) and activating transcription Factor 4 (ATF4) were increased in NaF-treated cells. The protein expression levels of key ER stress molecules (phosphorylated RNA-activated protein kinase-like ER-resident kinase (p-PERK), phosphorylated eukaryotic initiation factor-2α (p-eIF2α) and ATF4) were higher in NaF-treated cells.@*Conclusion@#A low concentration of NaF promotes the osteogenic/odontogenic differentiation of hDPCs and increases the level of ER stress.
ABSTRACT
Mucormycosis is an infectious disease characterized by rapidly progressive vascular invasiveness, thrombosis and tissue necrosis, which could be potentially responsible for blocking the exudation of leukocytes to infection sites and affecting drug distribution. Glucose-regulated protein 78 (GRP78) is a key protein involved in regulating the invasiveness of Mucorales. Endoplasmic reticulum GRP78 is overexpressed under various stress conditions and transported to the cell membrane to become a cell surface receptor for Mucorales entering into vascular endothelial cells. This article reviewed the mechanisms and pathogenesis of GRP78-mediated host cell invasion and summarized the progress in related targeted drugs, aiming to provide reference for developing multi-target intervention against mucormycosis.
ABSTRACT
Objective:To investigate the significance and level of serum GRP78 and GRP94 in the early stage ofacute pulmonary embolism.Methods:Ninety APE patients (APE group) and forty healthy controls (control group) in Affiliated Zhongshan Hospital of Dalian University from January 2018 to March 2020 were recruited. The level of serum D-Dimer, GRP78 and GRP94 were compared between the two groups. The pulmonary embolism group was divided into three groups according to guidelines for the diagnosis and treatment of pulmonary embolism in ESC in 2019: low risk, medium risk, high risk, The level of serum D-Dimer, GRP78, GRP94, blood gas, pulmonary arterial pressure, PESI mark of three groups were compared.Results:Two groups had no significant difference in sex, age, body mass index ( P>0.05), but the level of serum D-Dimer, GRP78 and GRP94 in control group and APE group were higher than those in the control group: (3.86 ± 1.82) mg/L vs. (0.31 ± 0.15) mg/L, (2.68 ± 0.71) μg/L vs. (1.64 ± 0.38) μg/L, (1.31 ± 0.29) μg/L vs. (0.98 ± 0.13) μg/L ( P<0.05). The levels of serum D-Dimer, GRP78, GRP94, pulmonary arterial pressure, PO2, PESI score of different degree group (low risk, medium risk, high risk) were higher than those of low risk group and medium risk group: (5.63 ± 1.75) mg/L vs. (2.29 ± 0.51) and (3.64 ± 1.02) mg/L, (3.24 ± 0.76) μg/L vs. (2.17 ± 0.41) μg/L and (2.64 ± 0.47) μg/L, (1.57 ± 0.33) μg/L vs. (1.12 ± 0.13) and (1.26 ± 0.14) μg/L, (47.75 ± 6.98) mmHg (1 mmHg = 0.133 kPa) vs. (26.15 ± 4.63) and (35.21 ± 5.85) mmHg, (123.5 ± 20.59) scores vs. (85.5 ± 14.31) and (102.5 ± 13.32) scores ( P<0.05), and that of medium risk group were higher than those of low risk group ( P<0.05). But PO 2 of high risk group was lower than that of low risk group and medium risk group ( P<0.05), and PO 2 of medium risk group was lower than that of low risk group ( P< 0.05). pH of three group had no significant difference ( P>0.05). PCO 2 of high risk group was lower than that of low risk group and medium risk group ( P<0.05), and PCO 2 of medium risk group and low risk group had no significant difference ( P>0.05). The level of serum D-Dimer, GRP78, GRP94 were positively correlated withPESI score ( r = 0.610, 0.622, 0.627, P<0.01). After treatment, the levels of D-Dimer, GRP78 and GRP94 were significantly decreased ( P<0.05). Conclusions:The level of serum GRP78 and GRP94 are connected with acute pulmonary embolism, and it can reflect the severity of the disease.
ABSTRACT
miR-340 can promote the proliferation and invasion of cancer cells, but how miR-340 regulates the occurrence and development of cancer in colon cancer is rarely reported. This study aims to explore the biological function and target gene regulation mechanism of miR-340 in colorectal cancer cells. Firstly, RT-qPCR was used to detect the expression level of miR-340 in different colorectal cancer cell lines, and then miR-340 was overexpressed or inhibited in COLO-205 cells. CCK-8, Transwell migration and invasion assay, and flow cytometry were performed to analyze the cell ability of proliferation, migration and invasion, as well as cell apoptosis and cell cycle. Finally, after bioinformatics prediction of miR-340 target genes, luciferase reporter gene and Western blot experiment were applied to verify those target genes. The results showed that miR-340 was downregulated in COLO-205 cells. Compared with the control group, cell proliferation, migration and invasion were significantly inhibited in the miR-340 overexpression group, but were promoted in the miR-340 suppression group (P<0. 01). The results of flow cytometry showed that the percentage of apoptosis in the miR-340 overexpression group was significantly increased, while the percentage of apoptosis in the miR-340 inhibition group was decreased (P<0. 01). The bioinformatics analysis of the overexpression miR-340 transfection group showed that the 3′UTR of glucose regulated protein 78 kD (GRP78) had a miR-340-5p binding site, and the luciferase activity was significantly reduced in the overexpression miR-340 group (P<0. 01); Western blot results also showed that overexpression of miR-340 can inhibit the expression of GRP78, while inhibiting miR-340 expression, the expression of GRP78 is relieved. In summary, miR-340 can directly target GRP78 to promote the apoptosis of COLO-205 cells and inhibit their proliferation, migration and invasion.
ABSTRACT
Aim To investigate whether endoplasmic reticulum stress is involved in the neurotoxicity of sodi¬um arsenite and clarify whether over-expression of 3-mercaptopyruvate sulfurtransferase (MPST) regulates endoplasmic reticulum stress induced by arsenic. Methods The SH-SY5Y cell line stably expressing the exogenous MPST gene was obtained by constructing the lentiviral vector of MPST gene. The SH-SY5Y cells were randomly divided into six groups, the SR-MPST over-expression group stably expressing the exogenous MPST gene, SH-PEB control group transfected with empty vector, the arsenite treatment group ( NaAs02 group ), TUDC A treatment group ( blocker of endoplasmic reticulum stress ) and TUDC A + NaAs02 group. Western blot was used to examine the protein expression of GRP78 and CHOP after different treatment. Results Although MPST overexpression had no significant effects on the expression of GRP78 and CHOP proteins, NaAs02 could significantly increased the protein levels of GRP78 and CHOP ( P < 0. 01 ) and the up-regulation of GRP78 and CHOP proteins caused by NaAs02 could be blocked by the treatment of TUDC A. In addition, the inhibition by MPST overexpression on the arsenic-induced increase of GRP78 and CHOP proteins (P <0. 01 ) could also be reversed by the TUDC A treatment significantly. Conclusions The GRP78/ CHOP endoplasmic reticulum stress pathway is involved in the neurotoxic damage induced by arsenic; MPST overexpression may decrease arsenic-induced endoplasmic reticulum stress.
ABSTRACT
Purpose: Enterovirus 71 (EV71) is one of the main pathogens causing hand, foot and mouth disease, which could even induce severe brain damage in some patients. As the underlying mechanism of the invasion and replication process still remains largely unknown, we investigated the role of candidate proteins expressed during EV71 invasion in human brain microvascular endothelial cells (HBMECs) to delineate the pathophysiological mechanism of EV-71 infection. Materials and Methods: Ninety-one candidate EV71-associated proteins which could bind the major capsid protein (viral protein 1 [VP1]) of EV71 on the HBMEC were identified by applying an analysis of glutathione-S-transferase pull-down coupling with liquid chromatography-electrospray ionisation-tandem mass spectrometry (LC-ESI-MS/MS). Seventy-eight kDa glucose-regulated protein 78 (GRP78) binding to the VP1 protein was further validated by co-immunoprecipitation, immunofluorescence and western blot analysis. To explore the role of GRP78 in EV71 infection, GRP78 was knocked down and overexpressed in HBMEC and was verified by TCID50 assay. Results: LC-ESI-MS/MS-identified 91 proteins were subjected to gene ontology analysis, and on molecular and biological function analysis revealed GRP78 act as an important binding protein in mediating EV71 infection. In addition, immunofluorescence demonstrated the co-localisation of GRP78 and VP1 in cytoplasm of the infected HBMEC. The TCID50 assay showed that knockdown of GRP78 could attenuate the replication capacity of EV71 in HBMEC, and the overexpression could increase the virus titre in HBEMC at 24 h post-infection suggesting that GRP78 was associated with the replication capacity of EV71 in HBMEC. Conclusion: These findings provided evidence that GRP78 plays an important role during the progression of EV71 infection as a mediator in HBMEC.
ABSTRACT
Aim: To explore the role of apoptosis stimulating protein 2 of p53 (ASPP2) on L-NAME induced apoptosis of placental trophoblast cells by regulating glucose-regulated protein78(GRP78), and provide a theoretical basis for the study of clinical pregnancy-induced hypertension. Methods: The HTR-8/SVneo human placental trophoblast cells were cultured in vitro, and in the absence (control group) or presence of 100 μmol · L-1 L-NAME (L-NAME group) for 48 h. The effects of L-NAME on placental trophoblast cell apoptosis were tested using flow cytometry and AO/EB assay. The expressions of caspase-12, GRP78 and ASPP2 were detected by Western blot. The ASPP2 interference with adenovirus was used to transfect the cells, and the mRNA expression level of ASPP2 and the protein expression level of GRP78 were detected by qRT-PCR and Western blot, respectively. After treated with 100 (xrnol · L-1 L-NAME for 48 h, the protein expression of caspase-12 and GRP78 was detected by Western blot and immunofluorescence. Results: Compared with control group, the placental trophoblast cell apoptosis significantly increased in L-NAME group (P < 0. 05). AO/EB staining showed that compared with control group, the majority of cells in L-NAME group showed bright orange and the number of late apoptotic cells increased significantly. At the same time, caspase-12, GRP78 and ASPP2 protein expression increased (P < 0. 05, P < 0. 01). After interfering with ASPP2, caspase-12 and GRP78 protein expressions decreased (P < 0. 05). Conclusions: Down-regulation of ASPP2 could decrease GRP78 expression and inhibit L-NAME-induced apoptosis in placental trophoblast cells.
ABSTRACT
Objective: To investigate the effects and mechanisms of iridoid glycosides of Scrophulariae Radix (IGRS) via endoplasmic reticulum stress-mediated apoptosis pathway on the primary cortical neurons induced by oxygen glucose deprivation/reperfusion (OGD/R). Methods: Newborn SD rats were performed primary cortical neurons culture. And the primary cortical neurons were pretreated with IGRS (50, 100, and 200 μg/mL) for 24 h, and the in vitro model of oxygen-glucose deprivation/reoxygenation (OGD/R) was applied. The neurons purity and morphology were observed under inverted microscope, the cell viability was detected by MTT assay; the intracellular lactate dehydrogenase (LDH) level and superoxide dismutase (SOD) activity were detected by commercial kit. The apoptotic rate was detected by flow cytometry. The expression of C/EBP homologous protein (CHOP), glucose-regulated protein-78 (GRP78) and Caspase-12 protein were detected by western blotting. Results: The cultured primary cortical neurons were plump with high purity in good condition. Compared with the control group, the primary cortical neurons were retracted and rounded after OGD/R treatment, and the surface of the neurons became rough; The cell viability and SOD activity were significantly decreased; The LDH level and apoptotic rate were evidently increased; The expression of CHOP, Caspase-12, and GRP78 were significantly increased. Compared with the model group, IGRS could relieve neurons damage, increase cell viability and SOD activity, decrease LDH level and apoptotic rate, and down-regulate the expression of CHOP, Caspase-12, and GRP78. Conclusion: IGRS can antagonize the neuronal damage induced by OGD/R in primary cortical neurons, and its mechanism is related to the inhibition of endoplasmic reticulum stress-mediated apoptosis.
ABSTRACT
Objective: To investigate the relationship between the expression of glucose-regulated protein 78 (GRP78) and gemcitabine chemotherapy in the patients with non-small cell lung cancer (NSCLC) and the effects of GRP78 on the viability of lung adenocarcinoma SPCA1 cells and the chemosensitivity of gemcitabine, and to elucidate its mechanisms. Methods: The positive expression rates of GRP78 in 32 cases of cancer tissue of the NSCLC patients were detected by immunohistochemical staining. The SPCA1 cells with high expression of GRP78 were selected as the subjects. RNA interference technique was used to down-regulate the expression of GRP78 in SPCA1 cells (interference group) and the cells treated with shNC were used as control group. MTT assay was used to detect the viabilities of SPCA1 cells in various groups. Negative control group, interference group, control + gemcitabine group, and interference+ gemcitabine group were set up; colone formation assay was used to detect the colone formation rates of SPCA1 cells in various groups; Western blotting method was used to detect the expression amount of Akt, p-Akt, PI3K, and p-PI3K in the SPCA1 cells in various groups. Results: The immunohistochemical staining results showed that the positive expression rate of GRP78 in cancer tissue in the remission NSCLC patients was significantly higher than that in the no-remission NSCLC patients after treated with gemcitabine (P<0. 05). The MTT assay results showed that compared with negative control group, the viability of SPCA1 cells in interference group was decreased significantly (P<0. 05), and the viability of SPCA1 cells in interference + gemcitabine group was significantly decresed (P<0. 05). The Western blotting results showed that compared with negative control group, the expression amounts of p-Akt and p-PI3K in the SPCA1 cells in interference group were decreased, and the expression amounts of p-Akt and p-PI3K in the SPCA1 cells in interference+gemcitabine group were decreased significantly. Conclusion: Interference of GRP78 may increase the sensitivity of gemcitabine to chemotherapy, and GRP78 may reduce the sensitivity of NSCLC patients to gemcitabine through PI3K/Akt pathway.
ABSTRACT
Oective: To investigate the expression of glucose regulating protein 78 (GRP78) in the sciatic nerve cells of the rats with diabetic peripheral neuropathy (DPN), and to elucidate the clinical significance and mechanism of Adjust Zang Dredge Meridian electroacupuncture in the treatment of DPN. Methods: A total of 86 adult male SD rats were divided into normal control group (n=5) and model group (n=81). The diabetic rat models were built through one-time injection of streptozocin (STZ), and then the diabetic rats were randomly divided into model control group (n=27), medicine intervention group (n=26), and electroacupuncture intervention group (n= 26). The rats in normal control group and model control group were fed with the maintenance feed. During the course of experiment, no special treatment was done for the rats in normal control group and model control group. The rats in drug intervention group were treated with intragastric administration of mecobalamin, 20 mg · kg-1 · d-1, once per day. The rats in electroacupuncture intervention group were treated with Adjust Zang Dredge Meridian electroacupuncture in the bilateral Feishu, Pishu, Shenshu, Hegu, Zusanli, Sanyinjiao and Taichong, once per day, 30 min per time. The thermal sensitivity value, motor nerve conduction velocity (MCV) and sensory nerve conduction velocity (SCV) of the tibial nerve of the rats in various groups were measured, the ultrastructures of sciatic nerve of the rats in various groups were observed under transmission electron microscope, the apoptotic rates of sciatic nerve cells of the rats in various groups were detected by TUNEL method, the expressions of GRP78 in sciatic nerve cells of the rats in various groups were detected by immumofluorescence, and the expression levels of GRP78 in sciatic nerve of the rats in various groups were detected by Western blotting method. Results: Compared with medicine intervention group, the thermal sensitivity value of the rats in electroacupuncture intervention group was significantly decresed (P<0. 01). Compared with model control group, the MCV and SCV of tibial nerve of the rats in medicine intervention group and electroacupuncture intervention group were increased after 12-week-intervention (P<0. 01); compared with before intervention, the MCV and SCV of tibial nerve of the rats in various groups were decreased after 12-week-intervention (P<0. 01). Under transmission electron microscope, some of the myelin sheath lamellae of sciatic nerve of the rats in model control group showed irregular membrane-like mass, and most of the thicker myelinated nerve fibers were seriously involved; the above changes were alleviated in medicine intervention group and electroacupuncture intervention group. The TUNEL assay results showed that compared with model control group, the apoptotic rates of sciatic nerve cells of the rats in medicine intervention group and electroacupuncture intervention group were significantly decreased (P < 0. 01). The Western blotting results showed that compared with model control group, the expression levels of GRP78 in sciatic nerve cells of the rats in medicine intervention group and electroacupuncture intervention group were significantly decreased (P < 0.05). Conclusion: Adjust Zang Dredge Meridian electroacupuncture can reduce the expression level of GRP78 in sciatic nerve cells of the DPN rats, inhibit the occurrence of endoplasmic reticulum stress (ERS), decrease the apoptotic rate of cells, and protect the nerves.
ABSTRACT
Glucose-regulated protein 78 (GRP78) plays an important role in the development of drug resistance in cancer, and GRP78 targeted therapy has become a hotspot of cancer research. In this article, we briefly introduce GRP78, review the research progress on the roles of GRP78 in drug resistance to cancer therapies, including chemotherapy, endocrine therapy and targeted therapy, and the mechanisms of resistance. The progress on GRP78 targeted therapy for cancer is also summarized.
ABSTRACT
<p><b>Objective</b>To investigate the correlation of the single nucleotide polymorphisms (SNPs) rs12009, rs1140763 and rs16927997 in the 3'-untranslated region (3'UTR) of the glucose-regulated protein 78 (GRP78) gene with the risk of male asthenozoospermia (AZS).</p><p><b>METHODS</b>We included 400 AZS patients in the AZS group and another 400 fertile men as normal controls. Using the SNaPshot technique, we genotyped the rs12009, rs1140763 and rs16927997 polymorphisms in the 3'UTR of the GRP78 gene in all the male subjects and analyzed the association of the three SNPs with AZS.</p><p><b>RESULTS</b>The percentage of progressively motile sperm was significantly lower in the AZS group than in the normal controls (［20.09 ± 8.18］ % vs ［57.16 ± 13.45］ %, P <0.01). Three genotypes of CC, CT and TT and 2 alleles of C and T were found in rs12009 and rs1140763 of the GRP78 gene, and another three genotypes of GG, GA and AA and two alleles of G and A were observed in rs16927997. There were no statistically significant differences between the control and AZS groups in the frequencies of the C and T alleles in rs12009 (44.3% vs 47.3% and 55.7% vs 52.7%, P >0.05) or rs1140763 (50.0% vs 52.0% and 50.0% vs 48.0%, P >0.05) or those of the G and A alleles in rs16927997 (6.0% vs 4.4% and 94.0% vs 95.6%, P >0.05), nor in the genotypes and allele frequencies of the 3 polymorphisms (P >0.05). Furthermore, three haplotypes of C-C-A, T-C-G and T-T-A were observed in the male subjects but showed no evident correlation between the AZS and normal control groups.</p><p><b>CONCLUSIONS</b>The polymorphisms in the 3'UTR of the GRP78 gene are not correlated with the risk of male asthenozoospermia.</p>
Subject(s)
Female , Humans , Male , 3' Untranslated Regions , Genetics , Alleles , Asthenozoospermia , Genetics , Gene Frequency , Genetic Predisposition to Disease , Genotype , Haplotypes , Heat-Shock Proteins , Genetics , Polymorphism, Single Nucleotide , RiskABSTRACT
Objective To explore the endoplasmic reticulum stress (ERS) apoptosis pathway in unilateral ureteral obstruction (UUO) mechanism of renal interstitial fibrosis in rats.Methods The rats were randomly divided into con-trol group and model group,UUO group line ligation of the left ureter,three days 3,7 and 14 days HE and Masson staining were used to observe the renal pathological changes;Take blood retinal venous plexus,separat and determina-tion of serum blood urea nitrogen and creatinine;Western blot was used to find protein 78 (GRP78) glucose regula-tion,endoplasmic reticulum source sex transcription factor (CHOP) and apoptosis related proteins cysteine aspartic acid proteinase 3(caspase-3) and caspase-12 protein expression. Results Compared with control group,the visible UUO model group 1) expansion of renal tubule and renal interstitial fibrosis degree with the extension of ureteral ob-struction time and progressive increase;2) GRP78,CHOP,caspase-3 and caspase-12 protein expression in postoper-ative 3 d have to rise,as the obstruction prolonged,the protein expression more significantly(P<0.01).Conclusions Endoplasmic reticulum stress related trademark protein in UUO rat renal interstitial fibrosis is the increase in expres-sion may promote the early renal interstitial fibrosis and continuous progress.
ABSTRACT
Objective To explore the endoplasmic reticulum stress (ERS) apoptosis pathway in unilateral ureteral obstruction (UUO) mechanism of renal interstitial fibrosis in rats.Methods The rats were randomly divided into con-trol group and model group,UUO group line ligation of the left ureter,three days 3,7 and 14 days HE and Masson staining were used to observe the renal pathological changes;Take blood retinal venous plexus,separat and determina-tion of serum blood urea nitrogen and creatinine;Western blot was used to find protein 78 (GRP78) glucose regula-tion,endoplasmic reticulum source sex transcription factor (CHOP) and apoptosis related proteins cysteine aspartic acid proteinase 3(caspase-3) and caspase-12 protein expression. Results Compared with control group,the visible UUO model group 1) expansion of renal tubule and renal interstitial fibrosis degree with the extension of ureteral ob-struction time and progressive increase;2) GRP78,CHOP,caspase-3 and caspase-12 protein expression in postoper-ative 3 d have to rise,as the obstruction prolonged,the protein expression more significantly(P<0.01).Conclusions Endoplasmic reticulum stress related trademark protein in UUO rat renal interstitial fibrosis is the increase in expres-sion may promote the early renal interstitial fibrosis and continuous progress.
ABSTRACT
Objective To investigate the expression of unfolded protein response (UPR) gene glucose regulated protein 78(GRP78) and X-box binding protein 1(XBP1) in esophageal squamous cell carcinoma, its effect on activation of the endoplasmic reticulum stress (ERS) and its mechanism in the growth of esophageal squamous cell carcinoma. Methods The expressions of GRP78 and XBP1 were detected by immunohistochemistry in 30 samples of esophageal squamous cell carcinoma and 30 samples of normal esophageal squamous epithelium. The correlation between expressions of both proteins and prognosis was analyzed. Results GRP78 positive rate was 83.3 %(25/30) in esophageal carcinoma, while the proportion was 20.0 %(6/30) in normal esophageal (χ2=25.833, P<0.05). XBP1 positive rate was 70.0 % (21/30) in esophageal carcinoma, while the proportion was 26.7%(8/30) in normal esophageal(χ2=20.872, P<0.05). The positive rates of GRP78 and XBP1 in invasive muscular layer of esophageal squamous cell carcinoma were significantly higher than those in invasive mucous layer. Conclusion GRP78 and XBP1 are highly expressed in esophageal squamous cell carcinoma, which may involve the occurrence and development of the esophageal carcinoma.
ABSTRACT
Early brain injury (EBI) plays a key role in the pathogenesis of subarachnoid hemorrhage (SAH). This study investigated the role of glucose-regulated protein 78 (GRP78) in EBI after SAH. Male Sprague-Dawley rats (n=108) weighing 260±40 g were divided into control, sham-operated, and operated groups. Blood was injected into the prechiasmatic cistern of rats in the operated group. Neurological scores, ultrastructures of neurons, apoptosis, and GRP78 expression in the hippocampus were examined using Garcia scoring system, transmission electron microscopy, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling, and Western blotting at 1, 6, 12, 24, 48, and 72 h after SAH, respectively. The results showed that neurological scores were significantly decreased in the operated group as compared with those in control and sham-operated groups at 12, 24, 48, and 72 h. Metachromatin, chromatin pyknosis at the edge, endoplasmic reticulum swelling, and invagination of nuclear membrane were observed at 24 h in the operated group, indicating the early morphological changes of apoptosis. The number of apoptotic cells was significantly increased in the operated group as compared with that in control and sham-operated groups at 6, 12, 24, 48, and 72 h. The GRP78 protein expression levels in the operated group were significantly elevated at all time points and reached the peak at 12 h. GRP78 expression was positively associated with apoptosis cells and negatively with neurological scores. In conclusion, EBI was demonstrated to occur after SAH and GRP78 was involved in the development of EBI after SAH.
Subject(s)
Animals , Male , Rats , Apoptosis , Brain Injuries , Metabolism , Pathology , Chromatin , Pathology , Endoplasmic Reticulum Stress , Heat-Shock Proteins , Genetics , Metabolism , Rats, Sprague-Dawley , Subarachnoid Hemorrhage , Metabolism , PathologyABSTRACT
Objective To investigate the function of melatonin (MEL)on liver transplantation by detecting the effect of MEL on glucose regulated protein-78 (GRP-78)and CCAAT enhancer-binding protein homologous protein (CHOP)involved in the endoplasmic reticulum stress (ERS)pathways in livers of rats with liver transplantation.Methods The rat orthotopic liver transplantation model was established by using‘magnetic-loop method’.Male SD rats were randomized into 3 groups:the sham operation group (Sham group),the orthotopic liver transplantation group (OLT group)and the orthotopic liver transplantation +MEL treatment group (OLT +MEL group),8 rats in each group.Serum sample and liver sample were collected at 24 h after operation.Serum alanine aminotransferase (ALT)and aspartate aminotransferase (AST)levels were detected.Liver tissues were stained with hematoxylin-eosin (HE)and pathological changes of liver tissues of each group were observed.The messenger ribonucleic acid (mRNA)and protein expression levels of GRP-78 and CHOP were detected by polymerase chain reaction and Western blot.Results Compared with the Sham group,the serum ALT and AST of the OLT group increased significantly (both in P <0.01 ),liver tissues injury was serious,and mRNA and protein expression levels of GRP-78 and CHOP increased significantly (all in P <0.01).Compared with the OLT group,ALT and AST of the OLT +MEL group decreased significantly (both in P <0.05),liver tissues injury was alleviated,and mRNA and protein expression levels of GRP-78 and CHOP decreased significantly (all in P <0.05 ).Conclusions MEL may reduce mRNA and protein expression levels of GRP-78 and CHOP involved in the ERS pathways of transplant liver,which may be one of its mechanisms to alleviate liver injury after liver transplantation.
ABSTRACT
Objective To observe the protective effect of Apelin-13 on the cerebral ischemia-reperfusion injury (CIRI), and to explore the possible mechanism in rat model. Methods Fifty male SD rats were randomly divided into five groups:sham group, CIRI model group and Apelin-13 (0.1, 1.0 and 10.0 μg/kg) treatment groups. The model of CIRI was established by filament. After 2 h ischemia, the focal middle cerebral artery was followed by 72 h reperfusion. Apelin-13 was administrated by intracerebroventricular injection 30 minutes before reperfusion. The score of neural function was estimated in different time points. The 2,3,5-triphenyl tetrazolium chloride (TTC) dye was used to calculate the volume and percentage of cerebral infarction. The endoplasmic reticulum stress (ERS) protein markers including glucose-regulated protein 78 (GRP78) and CCAAT/enhancer binding protein homologous protein (CHOP) in cerebral cortex were measured by Western blot assay. Results Compared with the sham group, the score of neural function was significantly increased, the infarct rate was reached(47.63 ± 5.81)%and the protein expressions of GRP78 and CHOP were significantly up-regulated in CIRI model group (P＜0.05). There were no significant differences in these data between the CIRI model group and 0.1 μg/kg Apelin-13 treatment group (P＞0.05). Compared with the CIRI group, the neural function defect was significantly improved, the muscle strength was significantly enhanced and the infarct rate was significantly decreased, and the protein expressions of GRP78 and CHOP were significantly down-regulated in the 1.0 and 10.0 μg/kg Apelin-13 treatment groups (P＜0.05). Conclusion Apelin-13 protects the cerebral ischemia-reperfusion injury in rat model, which may be related with the inhibition of endoplasmic reticulum stress.
ABSTRACT
Objective To explore the protective roles of Emodin in the intestinal mucosal lay of rats with severe acute pancreatitis (SAP) and its mechanism. Methods SD rats (n=30) were divided into 3 groups: sham operation group, SAP group and Emodin group (SAP rats treated with Emodin). The SAP rat models were established via retrograde injection of 3%sodium taurocholate to pancreatic duct. Rats in Emodin group were peritoneally injected with Emodin (2.5 mg/100 g) at both 1 hour and 3 hour after sodium taurocholate injection. Apoptosis of intestinal epithelial cell was detected by TUNEL analy?sis. The expression of glucose-regulated protein78 (GRP78) protein was assessed by immunohistochemistry. Results Com?pared with sham operation group, apoptosis in intestinal epithelial cells and the expression of GRP78 protein were increased significantly in SAP group(P0.05). Conclusion Emodin has a protective effect on intestinal layer in rats with SAP through inhibiting intestinal epithelial cell apoptosis. However, ER stress is not likely to be involved in this protective effect.
ABSTRACT
[ ABSTRACT] AIM:To investigate the effects of cerebral ischemia and postconditioning on protein kinase R-like endoplasmic reticulum kinase (PERK) and glucose-regulated protein 78 (GRP78) in the hippocampus tissue of tree shrew during endoplasmic reticulum stress and the mechanism of post-conditioning protecting the brain from damage.METH-ODS:The focal cerebral ischemic model was duplicated by photochemical reaction in tree shrew and the postconditioning was induced by alternatively occluding and opening the carotid artery of ischemic side for 3 cycles (5 min each cycle) at 3.5 h after ischemia.The damage and ultrastructural changes of the hippocampal neurons were observed by HE staining. The expression of PERK and GRP78 at mRNA and protein levels in the hippocampal tissue at different time points after cer-ebral ischemia and postconditioning was determined by RT-PCR, immunohistochemistry and Western blot.RESULTS:The injuries of hippocampal neurons were aggravated with prolonged cerebral ischemia, which was most severe at 24 h after ischemia while the postconditioning alleviated these damages correspondingly.The expression of PERK at mRNA and pro-tein levels was upregulated at 4 h, 24 h and 72 h after ischemia (P lated the expressions of GRP78 at IP24 h group (P<0.05).CONCLUSION:The focal thrombotic cerebral ischemia ac-tivates the endoplasmic reticulum stress in ischemic hippocampus of tree shrews, leading to the changes in mRNA and pro-tein expression of PERK in the PERK/eIF2αsignal transduction pathway.The postconditioning treatment alleviates endo-plasmic reticulum stress and neuronal damages by downregulating PERK and upregulating GRP78, thereby protecting the brain from injury.