OBJECTIVETo investigate the association between the pregnancy rate of intrauterine insemination (IUI) and the ERp57 expression level in donor sperm.

METHODSForty-two sperm samples were divided into 3 groups according to the pregnancy rate: Group A (n = 16, pregnancy rate = 0), B (n = 13, pregnancy rate 10%-20%) and C (n = 13, pregnancy rate > or = 20%). The optical density (OD) was normalized to the beta-tubulin band for the evaluation of the ERp57 level.

RESULTSOD (ERp57/Tubulin) was 0.95 +/- 0.24 in Group A, 1.33 +/- 0.43 in Group B and 1.33 +/- 0.39 in Group C. The ERp57 expression level was significantly lower in Group A than in B and C (P < 0.05), with no significant differences between the latter two groups.

CONCLUSIONThe ERp57 expression level in donor sperm could be used as an index to predict the pregnancy rate of IUI and to avoid IUI failure by removing low-level donor sperm.

Adult ; Female ; Humans ; Insemination, Artificial ; methods ; Male ; Pregnancy ; Pregnancy Rate ; Protein Disulfide-Isomerases ; metabolism ; Spermatozoa ; metabolism

OBJECTIVETo explore the effects of gastrin on the expression of 1,25(OH)2D3-membrane associated rapid response steroid (1,25D3-MARRS) binding protein in rat intestinal epithelium.

METHODSSD rats received intraperitoneal injections of gastrin, omeprazole or physiological saline. The protein expression of 1,25D3-MARRS binding protein in SD rat intestinal was determined with Western blotting and immunohistochemistry, and its mRNA levels determined by RT-PCR. The serum calcium and phosphate levels in the rats were also detected.

RESULTSImmunohistochemistry showed that 1,25D3-MARRS binding protein was expressed mainly in the nuclei, cytoplasm and membrane of the intestinal epithelial cells. Both the protein and mRNA expression levels of 1,25D3-MARRS binding protein were up-regulated after treatments with gastrin and omeprazole (P<0.05), but the serum calcium and phosphate concentrations showed no obvious increase.

CONCLUSION1,25D3-MARRS binding protein, which is widely expressed with versatile functionalities, is regulated by gastrin and shows high potentials in the study of gastrointestinal diseases.

Animals ; Calcitriol ; metabolism ; Epithelial Cells ; drug effects ; metabolism ; Gastrins ; pharmacology ; Intestines ; cytology ; drug effects ; Male ; Protein Disulfide-Isomerases ; metabolism ; Rats ; Rats, Sprague-Dawley

BACKGROUND/AIMS: Protein disulfide isomerase (PDI) has been implicated in the survival and progression of some cancer cells, by compensating for endoplasmic reticulum stress by upregulating the protein-folding capacity. However, its prognostic role in patients with hepatocellular carcinoma (HCC) has not been investigated. METHODS: We collected HCC tissues from 83 HCC patients who underwent surgical resection for an immunohistochemical study of PDI. Overall survival (OS) was measured from the date of surgical resection until the date of death from any cause. Radiological progression was evaluated using the modified Response Evaluation Criteria in Solid Tumors in an independent radiological assessment. RESULTS: PDI expression was found to be increased in human HCC compared to adjacent nontumor tissues. Increased immunopositivity for PDI was associated with a high Edmondson-Steiner grade (p = 0.028). Univariate analysis of patients who had undergone surgical resection for HCC showed that tumor PDI upregulation is a significant risk factor for poor OS (p = 0.016; hazard ratio [HR], 1.980) and time to progression (TTP; p = 0.007; HR, 1.971). Multivariate analyses revealed that high PDI expression was an independent predictor of a shorter TTP (p = 0.015; HR, 1.865) and poor OS (p = 0.012; HR, 2.069). CONCLUSIONS: Upregulated PDI expression is associated with aggressive clinicopathological features of HCC; thus, PDI might serve as an independent prognostic factor and a potential therapeutic target for HCC patients.
Carcinoma, Hepatocellular/*enzymology/pathology ; Female ; Humans ; Kaplan-Meier Estimate ; Liver Neoplasms/*enzymology/pathology ; Male ; Middle Aged ; Prognosis ; Protein Disulfide-Isomerases/*metabolism ; Retrospective Studies ; Tumor Markers, Biological/metabolism

OBJECTIVETo investigate the role of TXNDC5 in serum starvation-induced proliferation inhibition of HeLa cell.

METHODSTXNDC5 was either over-expressed or knocked down by small interfering RNA (siRNA) in HeLa cells which were then cultured in conventional medium or serum starvation medium. The protein level of TXNDC5 was evaluated by Western blot analysis. The mRNA level of TXNDC5 was measured by quantitative real-time PCR. Cell growth rate was determined by cell proliferation assay kit (MTS method). Cell cycle distribution and apoptosis were detected by flow cytometry.

RESULTSSerum starvation mildly reduced the mRNA level of TXNDC5 (P<0.05), but dramatically increased the protein level of TXNDC5 in HeLa cells. The stability of TXNDC5 mRNA remained unchanged. Cycloheximide abolished the serum starvation-induced up-regulation of TXNDC5 protein. Over-expression of TXNDC5 had no effect on cell proliferation. However, suppression of TXNDC5 attenuated the proliferation inhibition of HeLa cell induced by serum starvation (P<0.05), increased the proportion of cells in S phase (P<0.05), but had no effect on cell apoptosis.

CONCLUSIONTXNDC5 mediates serum starvation-induced proliferation inhibition of HeLa cell.

Apoptosis ; Cell Cycle ; Cell Proliferation ; Culture Media ; chemistry ; Gene Knockdown Techniques ; HeLa Cells ; Humans ; Protein Disulfide-Isomerases ; genetics ; metabolism ; Serum ; chemistry

The 1,095 bp gene encoding peroxidase from Coprinus cinereus was synthesized and integrated into the genome of Pichia pastoris with a highly inducible alcohol oxidase. The recombinant CiP (rCiP) fused with the a-mating factor per-pro leader sequence derived from Saccharomyces cerevisiae was secreted into the culture medium and identified as the target protein by mass spectrometry, confirming that a C. cinereus peroxidase (CiP) was successfully expressed in P. pastoris. The endoplasmic reticulum oxidoreductase 1 (Ero1) and protein disulfide isomerase (PDI) were co-expressed with rCiP separately and simultaneously. Compared with the wild type, overexpression of PDI and Erol-PDI increaseed Cip activity in 2.43 and 2.6 fold and their activity reached 316 U/mL and 340 U/mL respectively. The strains co-expressed with Erol-PDI was used to high density fermentation, and their activity reached 3,379 U/mL, which was higher than previously reported of 1,200 U/mL.
Coprinus ; enzymology ; Culture Media ; Cytoplasm ; Fermentation ; Glycoproteins ; metabolism ; Mass Spectrometry ; Mating Factor ; Oxidoreductases Acting on Sulfur Group Donors ; metabolism ; Peptides ; Peroxidases ; biosynthesis ; Pichia ; metabolism ; Protein Disulfide-Isomerases ; metabolism ; Protein Folding ; Saccharomyces cerevisiae ; Saccharomyces cerevisiae Proteins ; metabolism

Disulfide bond formation protein A, DsbA, is one of the important proteins located in E. coli periplasm, which is a foldase facilitating the folding of nascent secreted proteins, especially for those with many pairs of disulfide bonds. The crystal structure and phylogenetic analysis of DsbA and DsbA-mediated protein folding, alternatively in vivo and in vitro, are summarized. Both the extremely low pKa of Cys30 , about 3.5, and the destabilizing effect of the active site disulfide contribute to its strong oxidizing power. The Cys30 is also considered as the most important residue closely related to its activity using site-directed mutagenesis methodology. DsbA could effectively assist proteins folding, both in vivo coexpressed with the target protein, and in vitro replenished as foldases. Moreover, DsbA also has the chaperone-like activity in the assistant refolding of genetically engineered inclusion bodies.
Amino Acid Sequence ; Disulfides ; chemistry ; metabolism ; Escherichia coli ; enzymology ; genetics ; Escherichia coli Proteins ; chemistry ; classification ; metabolism ; Models, Molecular ; Molecular Sequence Data ; Phylogeny ; Protein Disulfide-Isomerases ; chemistry ; classification ; metabolism ; Protein Folding ; Protein Structure, Tertiary ; Sequence Homology, Amino Acid

OBJECTIVETo determine the effect of butylphthalide on the expressions of protein disulfide isomerase (PDI) and P53 in the brain tissue of rats with Alzheimer's disease (AD).

METHODSSixty male adult rats were randomly divided into AD model group, butylphthalide group and control group (n = 20). AD models were established by injecting beta-amyloid protein 1-42 into the hippocampus of rats. Sixty days later, the learning and memory abilities of the rats were evaluated using Y-maze test, and the expressions of PDI and P53 in the brain tissue of the rats were measured by immunohistochemistry.

RESULTSCompared with the control group, the rats in AD model group exhibited significantly reduced learning and memory abilities, lowered expressions of PDI in the hippocampus and increased expression of P53 in the cortex (P > 0.01). In comparison with the model group, the rats in the butylphthalide group showed significantly increased PDI-positive cells in the hippocampus and decreased expression of P53 in the cortex (P < 0.01).

CONCLUSIONButylphthalide improves the learning and memory abilities of rats with experimental AD, the mechanism of which may involve inhibition of P53 expression and enhancement of PDI expression in the brain tissues.

Alzheimer Disease ; physiopathology ; Animals ; Apoptosis ; drug effects ; Benzofurans ; pharmacology ; Brain ; enzymology ; metabolism ; Disease Models, Animal ; Learning ; drug effects ; Male ; Memory ; drug effects ; Protein Disulfide-Isomerases ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Tumor Suppressor Protein p53 ; metabolism

OBJECTIVE: To determine the screening of the expression of membrane proteins in androgen-dependent prostate cancer (ADPC) and androgen-independent prostate cancer (AIPC) and to explore the mechanism of membrane proteins in these two cancers. METHODS: Serum samples were collected from 3 patients with ADPC and another 3 patients with AIPC. The serum was incubated with ADPC cell line LNCaP and/or AIPC cell line PC-3 and detected by immunoprecipitation and Western blot. Differentially expressed proteins between ADPC and AIPC identified by mass spectrometry were compared and their expression level and location were analyzed by immunofluorescence. RESULTS: Altogether 11 membrane proteins were identifited, such as the Neural-Cadherin precursor, ER60 precursor, Claudin-4, and so on. Immunofluorescence revealed that the expression level of Claudin-4 in PC-3 cells was higher than in LNCaP cells. CONCLUSION We can use the screening method to study membrane proteins in prostate cancer. Claudin-4 may play an important role in the pathogenesis and the development of AIPC.
Aged ; Androgens ; genetics ; metabolism ; Cell Line, Tumor ; Claudin-4 ; genetics ; metabolism ; Gene Expression Profiling ; Humans ; Male ; Membrane Glycoproteins ; genetics ; metabolism ; Prostatic Neoplasms ; genetics ; metabolism ; pathology ; Protein Disulfide-Isomerases ; genetics ; metabolism

OBJECTIVETo study the predicting effect of proly 4-hydroxylase beta polypeptide (P4HB) in treating non-small cell lung cancer (NSCLC) patients by Yiqi Chutan Recipe (YCR).

METHODSTotally 46 stage III and IV NSCLC patients were treated by YCR for 4 therapeutic courses. Effect was assessed by RECIST of solid tumor. P4HB expression was detected in the lung cancer tissue by immunohistochemical assay. Factors affecting disease control rates (DCR) of YCR were analyzed by Logistic regression analysis. The correlation between P4HB expression and the effect of YCR was analyzed.

RESULTSThe DCR of advanced NSCLC treated by YCR was 36.96% (17/46 cases). P4HB was high expressed in advanced lung cancer tissue (6/15 cases). Gender, initial treatment, and retreatment are independent factors for affecting DCR of treating lung cancer by YCR.

CONCLUSIONP4HB might be taken as a factor for predicting the effect of YCR in treating NSCLC.

Carcinoma, Non-Small-Cell Lung ; drug therapy ; metabolism ; Drugs, Chinese Herbal ; therapeutic use ; Humans ; Lung ; Lung Neoplasms ; drug therapy ; metabolism ; Male ; Procollagen-Proline Dioxygenase ; metabolism ; Protein Disulfide-Isomerases ; metabolism

Disulfide bond-forming (Dsb) protein is a bacterial periplasmic protein that is essential for the correct folding and disulfide bond formation of secreted or cell wallassociated proteins. DsbA introduces disulfide bonds into folding proteins, and is re-oxidized through interaction with its redox partner DsbB. Mycobacterium tuberculosis, a Gram-positive bacterium, expresses a DsbA-like protein ( Rv2969c), an extracellular protein that has its Nterminus anchored in the cell membrane. Since Rv2969c is an essential gene, crucial for disulfide bond formation, research of DsbA may provide a target of a new class of anti-bacterial drugs for treatment of M.tuberculosis infection. In the present work, the crystal structures of the extracellular region of Rv2969c (Mtb DsbA) were determined in both its reduced and oxidized states. The overall structure of Mtb DsbA can be divided into two domains: a classical thioredoxin-like domain with a typical CXXC active site, and an α-helical domain. It largely resembles its Escherichia coli homologue EcDsbA, however, it possesses a truncated binding groove; in addition, its active site is surrounded by an acidic, rather than hydrophobic surface. In our oxidoreductase activity assay, Mtb DsbA exhibited a different substrate specificity when compared to EcDsbA. Moreover, structural analysis revealed a second disulfide bond in Mtb DsbA, which is rare in the previously reported DsbA structures, and is assumed to contribute to the overall stability of Mtb DsbA. To investigate the disulphide formation pathway in M.tuberculosis, we modeled Mtb Vitamin K epoxide reductase (Mtb VKOR), a binding partner of Mtb DsbA, to Mtb DsbA.
Amino Acid Sequence ; Bacterial Proteins ; chemistry ; metabolism ; Catalytic Domain ; Crystallography, X-Ray ; Disulfides ; chemistry ; Escherichia coli ; metabolism ; Escherichia coli Proteins ; chemistry ; metabolism ; Molecular Docking Simulation ; Molecular Sequence Data ; Mycobacterium tuberculosis ; metabolism ; Oxidation-Reduction ; Protein Disulfide-Isomerases ; chemistry ; metabolism ; Protein Folding ; Protein Structure, Tertiary ; Sequence Alignment ; Static Electricity