Hypothalamic proline-rich polypeptide is a regulator of oxidative burst in human neutrophils and monocytes

Morpho‑functional study of the hypothalamic proline‑rich polypeptide apoptotic activity against mouse Ehrlich ascites carcinoma

A new type of bioactive polypeptides of the neurosecretory hypothalamus called proline‑rich peptides (PRPs), which are isolated from bovine neurosecretory granules of the neurohypophysis, are synthesized in the form of a common precursor protein (neurophysin vasopressin‑associated glycoprotein). Proline‑rich polypetide 1 (PRP‑1; also known as galarmin) is comprised of 15 amino acids residues, and has been suggested to possess anti‑neurodegenerative, immunoregulatory, hematopoietic, antimicrobial and antitumor properties. The cytostatic, antiproliferative effect of PRP‑1 was demonstrated in the human chondrosarcoma JJ012 and triple negative breast carcinoma MDA MB 231 cell lines. PRP‑1 action is disease and tissue specific. To further explore the antitumorigenic and possible cytotoxic effects of PRP‑1, a morpho‑functional study on the effect of PRP‑1 on a mouse Ehrlich ascites carcinoma (EAC) model was conducted. The PRP‑1‑induced morphological features of EAC cells confirmed the apoptotic nature of PRP‑1, as manifested by cell shrinkage, membrane blebbing, chromosome condensation (pyknosis) and nuclear fragmentation (karyorrhexis). The effect of PRP‑1 on the number of tumor cells incubated for 24 h and their viability in trypan blue‑stained samples lead to a 44% reduction in the number of viable cells on day 11 post‑inoculation vs. 22% inhibition of viable cells after PRP‑1 treatment (0.1 µg/ml) on day 7 post‑inoculation. Apoptosis experiments using an Annexin V‑cyanine 3 apoptosis detection kit indicated that 24 h incubation with 0.1 µg/ml PRP‑1 caused a significant increase in the number of apoptotic cells, reaching 50.33%, compared to 8.33% in the sample control on day 7 post‑inoculation.

Association of Circulating Transfer RNA fragments with antibody response to Mycoplasma bovis in beef cattle

Background

High throughput sequencing allows identification of small non-coding RNAs. Transfer RNA Fragments are a class of small non-coding RNAs, and have been identified as being involved in inhibition of gene expression. Given their role, it is possible they may be involved in mediating the infection-induced defense response in the host. Therefore, the objective of this study was to identify 5′ transfer RNA fragments (tRF5s) associated with a serum antibody response to M. bovis in beef cattle.

Results

The tRF5s encoding alanine, glutamic acid, glycine, lysine, proline, selenocysteine, threonine, and valine were associated (P < 0.05) with antibody response against M. bovis. tRF5s encoding alanine, glutamine, glutamic acid, glycine, histidine, lysine, proline, selenocysteine, threonine, and valine were associated (P < 0.05) with season, which could be attributed to calf growth. There were interactions (P < 0.05) between antibody response to M. bovis and season for tRF5 encoding selenocysteine (anticodon UGA), proline (anticodon CGG), and glutamine (anticodon TTG). Selenocysteine is a rarely used amino acid that is incorporated into proteins by the opal stop codon (UGA), and its function is not well understood.

Conclusions

Differential expression of tRF5s was identified between ELISA-positive and negative animals. Production of tRF5s may be associated with a host defense mechanism triggered by bacterial infection, or it may provide some advantage to a pathogen during infection of a host. Further studies are needed to establish if tRF5s could be used as a diagnostic marker of chronic exposure.

Descriptive epidemiology of World Health Organization grades II and III intracranial meningiomas in the United States

BACKGROUND

Because World Health Organization (WHO) grades II and III meningiomas are relatively uncommon, there is limited literature on the descriptive epidemiology of these tumors, and the existing literature predates the 2000 WHO classification revisions. Our purpose was to provide a modern, population-based study of the descriptive epidemiology of WHO II and III meningiomas in the United States.

METHODS

The Central Brain Tumor Registry of the United States (CBTRUS) was queried for intracranial meningiomas categorized by WHO grade for the 2004--2010 study period. Age-adjusted incidence (95% confidence interval in parentheses) per 100,000 population was calculated by age, sex, race, and ethnicity. Annual percent change (APC) was calculated using Joinpoint.

RESULTS

From 2004 to 2010, the incidence of WHO II intracranial meningiomas increased from 0.28 (95% CI, 0.27--0.29) to 0.30 (95% CI, 0.28-0.32), representing an APC of 3.6% (95%CI, 0.8%-6.5%). Conversely, from 2000-2010, the incidence of WHO III meningiomas decreased from 0.13 (95% CI, 0.11-0.14) to 0.06 (95%CI, 0.06-0.07), representing an APC of -5.4% (95% CI, -6.8% to -4.0%). From 2004 to 2010, the overall proportion of WHO I, II, and III intracranial meningiomas was 94.6%, 4.2%, and 1.2%, respectively. For WHO II/III meningiomas, females in the 35-64 year age group had a higher incidence than males in the same age group, whereas males in the ≥ 75 year age group ≥ had a higher incidence. Black and Asian Pacific Islander races were both associated with the highest incidence of WHO II/III meningiomas. Hispanic ethnicity was not associated with any difference in incidence.

CONCLUSION

This study presents the most comprehensive evaluation of the modern descriptive epidemiology of WHO II and III meningiomas. Temporal trends likely reflect the 2000 WHO histological criteria revisions.

Sampling human indigenous saliva peptidome using a lollipop-like ultrafiltration probe: simplify and enhance peptide detection for clinical mass spectrometry

Although human saliva proteome and peptidome have been revealed they were majorly identified from tryptic digests of saliva proteins. Identification of indigenous peptidome of human saliva without prior digestion with exogenous enzymes becomes imperative, since native peptides in human saliva provide potential values for diagnosing disease, predicting disease progression, and monitoring therapeutic efficacy. Appropriate sampling is a critical step for enhancement of identification of human indigenous saliva peptidome. Traditional methods of sampling human saliva involving centrifugation to remove debris may be too time-consuming to be applicable for clinical use. Furthermore, debris removal by centrifugation may be unable to clean most of the infected pathogens and remove the high abundance proteins that often hinder the identification of low abundance peptidome. Conventional proteomic approaches that primarily utilize two-dimensional gel electrophoresis (2-DE) gels in conjugation with in-gel digestion are capable of identifying many saliva proteins. However, this approach is generally not sufficiently sensitive to detect low abundance peptides/proteins. Liquid chromatography-Mass spectrometry (LC-MS) based proteomics is an alternative that can identify proteins without prior 2-DE separation. Although this approach provides higher sensitivity, it generally needs prior sample pre-fractionation and pre-digestion with trypsin, which makes it difficult for clinical use. To circumvent the hindrance in mass spectrometry due to sample preparation, we have developed a technique called capillary ultrafiltration (CUF) probes. Data from our laboratory demonstrated that the CUF probes are capable of capturing proteins in vivo from various microenvironments in animals in a dynamic and minimally invasive manner. No centrifugation is needed since a negative pressure is created by simply syringe withdrawing during sample collection. The CUF probes combined with LC-MS have successfully identified tryptic-digested proteins. In this study, we upgraded the ultrafiltration sampling technique by creating a lollipop-like ultrafiltration (LLUF) probe that can easily fit in the human oral cavity. The direct analysis by LC-MS without trypsin digestion showed that human saliva indigenously contains many peptide fragments derived from various proteins. Sampling saliva with LLUF probes avoided centrifugation but effectively removed many larger and high abundance proteins. Our mass spectrometric results illustrated that many low abundance peptides became detectable after filtering out larger proteins with LLUF probes. Detection of low abundance saliva peptides was independent of multiple-step sample separation with chromatography. For clinical application, the LLUF probes incorporated with LC-MS could potentially be used in the future to monitor disease progression from saliva.

The protective and immunomodulatory effects of hypothalamic proline-rich polypeptide galarmin against methicillin-resistant Staphylococcus aureus infection in mice

The present research summarizes the protective and immunomodulatory activity of hypothalamic proline-rich polypeptide galarmin against methicillin-resistant Staphylococcus aureus (MRSA). The protective effect of galarmin was shown on MRSA-infected animals' survival and weight loss recovery. The immunological impact of galarmin was evaluated in terms of immunocompetent cell recruitment, serum immunoglobulins, complement components C3 and C4, and pro- and anti-inflammatory cytokines (IL-6, IL-8, IL-10, IL-1b, TNFa, and KC) secretion. Galarmin efficiently protects mice against lethal MRSA infection (100% of survival vs. 0% in the untreated group) when intramuscularly injected 24 h before infection and during the 1-h post-infection period at a concentration of 1 μg per mouse, while its higher concentrations (5 and 10 μg) were protective when injected in parallel to the infection process. The protective effect of galarmin was not due to a direct effect on MRSA, but should be attributed to an action on the host response to infection. Galarmin significantly increased and modulated the levels of IL-6, IL-8, IL-1b, IL-10, and KC in both peritoneal lavages and blood, leukocyte and platelet counts, lymphocytes percentage, serum IgM and IgG, and complement C3 and C4 components secretion. The experimental results allow concluding that galarmin is a powerful immunomodulatory and protective agent for the in vivo prophylaxis and treatment of MRSA-induced infection.

Antioxidant and electron donating function of hypothalamic polypeptides: galarmin and Gx-NH2

Chemical mechanisms of antioxidant and electron donating function of the hypothalamic proline-rich polypeptides have been clarified on the molecular level. The antioxidant-chelating property of Galarmin and Gx-NH(2) was established by their capability to inhibit copper(II) dichloride catalyzed H(2)O(2) decomposition, thus preventing formation of HO(*) and HOO(*) radicals. The antiradical activity of Galarmin and Gx-NH(2) was determined by their ability to react with 2,2-diphenyl-1-picrylhydrazyl radical applying differential pulse voltammetry and UV-Vis spectrophotometry methods. Galarmin manifest antiradical activity towards 2,2-diphenyl-1-picrylhydrazyl radical, depending on the existence of phenolic OH group in tyrosine residue at the end of the molecule. The presence of antiradical activity and reduction properties of Galarmin are confirmed by the existence of an oxidation specific peak in voltammograms made by differential pulse voltammetry at E ( composite function) = 0.795 V vs. Ag/Ag(+) aq.

Hypothalamic proline rich polypeptide regulates hematopoiesis

The AGAPEPAEPAQPGVY proline-rich polypeptide (PRP-1) was isolated from neurosecretory granules of the bovine neurohypophysis; it is produced by N. supraopticus and N. paraventricularis. It has been shown that PRP-1 has many potentially beneficial biological effects including immunoregulatory, hematopoietic, antimicrobial and anti-neurodegenerative properties. Here we demonstrated that PRP-1 administration influence on redistribution of monocytes, granulocytes and lymphocytes between bone marrow (BM) and peripheral blood and promotes the influx of granulocytes and monocytes/macrophages from BM into peripheral blood and accumulation of immature granulocyte and monocyte in BM and delayed the maturation of T cells in BM. PRP-1 increased colony-forming cell proliferation in rat cells in vivo. In PRP-treated rat BM, the CFU number at day 4, 7 and 14 was considerably increased in comparison with untreated rats BM and no difference was found at day 21 and day 28. We found that PRP-1 enhances erythroid and myeloid colonies formation in human CD34(+) progenitor cell culture in the presence of different growth factors and down-regulates T cells colony formation and specific surface markers expression during induction of human CD34(+) progenitor cells differentiation into T lymphocytes lineage. We suggested that the hypothalamic PRP-1 possibly represents an endogenous peptide whose primary functions are to regulate neuronal survival and differentiation and hematopoiesis within neurosecretory hypothalamus-bone marrow humoral axis.

Hypothalamic Proline-Rich Polypeptide Enhances Bone Marrow Colony-Forming Cell Proliferation and Stromal Progenitor Cell Differentiation

The AGAPEPAEPAQPGVY proline-rich peptide (PRP-1) was isolated from neurosecretory granules of the bovine neurohypophysis; it is produced by N. supraopticus and N. paraventricularis. It has been shown that PRP-1 has many potentially beneficial biological effects, including immunoregulatory, hematopoietic, antimicrobial, and antineurodegenerative properties. Here we showed that PRP increased colony-forming cell (CFC) proliferation in rat bone marrow (BM) cells in vivo. In PRP-treated rat BM, the CFU number at day 7 and day 14 was considerably increased in comparison with untreated rat BM and no difference was found at day 21 and day 28. The related peptide [arg8]vasopressin did not reveal CFC proliferation. PRP failed to farther increase CFC proliferation in vitro in BM obtained from PRP-treated or untreated rats. After 3–4 days of human BM stromal cell cultivation in the presence of 2–20 μg/ml PRP the appearance of cells expressing CD15, CD10, CD11a, CD11b, CD3, CD4, and CD16 surface antigens did not differ from the untreated cells. PRP increased the appearance of CD14-positive cells upon 3–4-day incubation with both adult and fetal BM stromal cells. Our results suggest a previously undescribed role for the hypothalamic peptide within neurosecretory hypothalamus–bone marrow humoral axis, because PRP enhances BM colony-forming cell proliferation and stromal cell differentiation.

A peptide with a ProGln C terminus in the human saliva peptidome exerts bactericidal activity against Propionibacterium acnes

Nine proline-rich peptides ending with a proline-glutamine C terminus in a salivary peptidome were sequenced by matrix-assisted laser desorption ionization time of flight time of flight tandem mass spectrometry. A GPPPQGGRPQ peptide binds gram-positive Propionibacterium acnes and considerably inhibits bacterial growth. The peptide exhibiting innate immunity may be applied for treatment of various P. acnes-associated human diseases.

Effect of Hypothalamic Proline-Rich Peptide (PRP-1) on Neuronal and Bone Marrow Cell Apoptosis

The AGAPEPAEPAQPGVY proline-rich peptide (PRP-1) was isolated from neurosecretory granules of the bovine neurohypophysis; it is produced by N. supraopticus and N. paraventricularis. It has been shown that PRP-1 has many potentially beneficial biological effects including immunoregulatory, hematopoietic, antimicrobial and anti-neurodegenerative properties. Here we investigated the influence of PRP-1 on staurosporine-induced apoptosis of postnatal hippocampal cells and on doxorubicin-induced bone marrow granulocyte- and monocyte apoptosis. The intention was to further characterize the effect of PRP-1 on the survival rate of neurons and in context with myelopoiesis. We demonstrate that PRP-1 significantly reduced apoptosis of postnatal hippocampal cells induced by staurosporine. The protective effect of PRP-1 against apoptotic cell death was shown to be both time- and dose-dependent. Neuroprotection was more pronounced after prolonged pretreatment of the cells with PRP-1 before the induction of apoptosis with staurosporine. The related peptide [arg(8)]vasopressin did not reveal neuroprotection. PRP-1 also significantly reduced apoptosis of bone marrow monocytes and granulocytes induced by doxorubicin. This protective effect lasted for 2-4 h and was not detectable anymore after 24 h when PRP-1 and doxorubicin were added simultaneously. Previously obtained data and results of the current studies suggested that the hypothalamic PRP-1 possibly represents an endogenous peptide whose primary functions are to regulate myelopoiesis and neuron survival as we provide evidence that PRP can differentially reduce both staurosporine- and doxorubicin-induced hippocampal and bone marrow cell apoptosis.