OBJECTIVETo investigate both PrP and PrP106-126 peptide effect on 14-3-3beta dimeration.

METHODS14-3-3beta were incubated with different does recombinant PrP or PrP106-126 peptide, both 14-3-3beta dimer and polymer were separated 15% non-denaturing polyacrylamide gel electrophoresis (PAGE) and the 14-3-3 dimers were evaluated using 14-3-3beta-specific Western blotting. And then,14-3-3beta dimeration buffer were incubated with different does recombinant PrP and 250 micromol/L PrP106-126 peptide, 14-3-3beta dimer and polymer were detected by above methods. Cellular 14-3-3 dimer were also detected after PrP106-126 peptide were added to HeLa cell for 8 hours.

RESULTSRecombinant full-length PrP facilitated the dimerization of 14-3-3beta and PrP106-126 disturbed 14-3-3beta dimeration as both have dose dependence effect. PrP antagonized PrP106-126-induced 14-3-3beta dimer with PrP protein increase in vitro. Cellular 14-3-3 dimerization also decreased after treatment of peptide PrP106-126 on HeLa cells for 8 hours.

CONCLUSION[corrected] Dimerization process of 14-3-3beta was promoted by full-length PrP (PrP23-231) but inhibited by peptide PrP106-126 in vitro. PrP agonized PrP106-126-induced inhibition of 14-3-3 dimeration. PrP106-126 inhibited cellular 14-3-3 dimerization.

14-3-3 Proteins ; chemistry ; HeLa Cells ; Humans ; Peptide Fragments ; pharmacology ; Prions ; pharmacology ; Protein Multimerization ; drug effects ; Recombinant Proteins ; pharmacology

The angiogenesis induced with neotype amphiphilic peptide containing Isoleucine-Lysine-Valine-Alanine-Valine (IKVAV) was explored in vivo. The peptide was self-assembled into hydrogel, confirmed using transmission electron microscopy (TEM). One millilitre of 10 mg/ml peptide (experiment group, EG) and 16.67% gelatin (control group, CG) were injected subcutaneously beside rat backbone. The systemic response and local skin were observed one week after injection. The specimens were harvested two weeks later and immunohistochemically examined for vascular endothelial growth factor (VEGF). TEM showed that hydrogel was composed of interconnected nanofibers. The inflammatory reaction and necrosis of local skins were not found one week after injection. Lots of capillary vessels with complete wall were found within self-assembled peptide hydrogel, with erythrocytes noted inside the vessels in EG; the capillary vessels or erythrocytes were not found in the gelatin in CG. The immunohistochemical detection revealed VEGF-positive cells in EG, which were not found in CG. The self-assembly hydrogel from IKVAV-containing peptide was able to induce the angiogenesis in vivo.
Animals ; Hydrogels ; pharmacology ; Laminin ; pharmacology ; Neovascularization, Physiologic ; drug effects ; Peptide Fragments ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Skin ; blood supply

Bovine adrenal medulla 22 (BAM22), an endogenous opioid peptide, is one of the cleavage products of proenkephalin A. It potently activates opioid receptors and sensory neuron-specific receptor (SNSR). The present study was aimed at investigating the effect of BAM22 on morphine tolerance. Intrathecal (i.t.) administration of morphine for 7 d produced morphine tolerance in rats. Then the rats were divided into three groups in which morphine, saline or BAM22 were administered i.t., respectively, on day 8, and morphine was given to all of the animals on day 9. It was found that morphine administered on day 9 resumed antinociceptive effects in BAM22 group, but not in saline or morphine group. The potency of morphine in BAM22 group was 48.5% of the maximal possible effect (MPE) detected by paw withdrawal test and the antinociception persisted for approximately 1 h. Following the similar treatment, morphine administered on day 9 reduced nocifensive behaviors by 3.2 min and 24 min in BAM22 group in the first and second phases, in the formalin test, respectively. The decreases were 45% and 82% of the corresponding values observed in saline group. Furthermore, following the treatment with BAM22 (10 nmol) on day 8 in morphine-tolerance rats, morphine administered on day 9 decreased the expressions of the heat-evoked c-Fos-like immunoreactivity (FLI) protein by approximately 80% in laminae I-II, III-IV and V-VI in the spinal cord at L4-L5 compared with that in saline or morphine group. The present study provided evidence at behavioral and cellular levels showing that BAM22 resumed antinociception of morphine. The results that the reversal effect of BAM22 on morphine tolerance was more efficient in persistent pain model than in acute pain may indicate that BAM22 differentially modulates morphine tolerance. The present study suggests that SNSR is involved in the modulation of morphine tolerance.
Animals ; Drug Tolerance ; Enkephalins ; pharmacology ; Morphine ; pharmacology ; Pain ; drug therapy ; Peptide Fragments ; pharmacology ; Rats ; Receptors, G-Protein-Coupled ; metabolism

Tissue factor pathway inhibitor (TFPI) is one of the major physiological inhibitors of the human blood coagulation cascade and may have great potential in the prevention and therapy of diseases caused by thrombus formation. In this study, recombinant human tissue factor was generated in E. coli containing a recombinant vector constructed by inserting TFPI cDNA into pGEX-2T vector. The generated recombinant TFPI (rTFPI) could be simply purified with glutathione-agarose affinity method and maintained its biological function in terms of inhibition of tissue factor and factor Xa.
Escherichia coli ; genetics ; metabolism ; Humans ; Lipoproteins ; biosynthesis ; genetics ; pharmacology ; Peptide Fragments ; biosynthesis ; genetics ; pharmacology ; Plasmids ; Recombinant Proteins ; biosynthesis ; pharmacology ; Transfection

Amyloid beta-Peptides ; toxicity ; Animals ; Drugs, Chinese Herbal ; pharmacology ; Estradiol ; pharmacology ; PC12 Cells ; Peptide Fragments ; toxicity ; Rats

Animals ; Rats ; Neuroprotective Agents/pharmacology* ; Amyloid beta-Peptides ; PC12 Cells ; Polyunsaturated Alkamides/pharmacology* ; Apoptosis ; Cell Survival ; Peptide Fragments

Carcinoma, Hepatocellular ; pathology ; Humans ; Liver Neoplasms ; pathology ; Neoplasm Invasiveness ; Neoplasm Metastasis ; Peptide Fragments ; pharmacology ; Peptides ; pharmacology ; Tumor Cells, Cultured

To investigate changes of 14-3-3beta from apoptosis induced by PrP106-126 polypeptide, HeLa cell was incubated with PrP106-126 for 4h or 8h. Nucleus changes and the expression of PARP were detected differently by Hoechst staining and Western blotting. Expressing of protein and mRNA from 14-3-3beta was determined by Western blotting and Real-time PCR. The results show that typical nucleus pyknosis and chip of apoptosis and degradation of PARP were induced by PrP106-126 peptide in HeLa cells. Degradation of 14-3-3beta appeared in apoptosis groups induced by PrP106-126 peptide. However, 14-3-3beta mRNA did not display any changes in apoptosis groups. This study indicated that degradation of antiapoptosis protein 143-3beta induced by PrP106-126 peptide may be one of pathogenesis mechanism of prion disease.
14-3-3 Proteins ; metabolism ; Apoptosis ; drug effects ; HeLa Cells ; Humans ; Peptide Fragments ; pharmacology ; Prions ; pharmacology ; Proteolysis ; drug effects

Animals ; Galanin ; administration & dosage ; antagonists & inhibitors ; pharmacology ; Patch-Clamp Techniques ; Peptide Fragments ; administration & dosage ; pharmacology ; Rats ; Rats, Wistar

Animals ; Animals, Newborn ; Cells, Cultured ; Cyclic AMP ; metabolism ; Glucagon-Like Peptide 1 ; pharmacology ; Insulin ; secretion ; Islets of Langerhans ; drug effects ; secretion ; Peptide Fragments ; pharmacology ; RNA, Messenger ; genetics ; Rats