Analysis of proopiomelanocortin (POMC) messenger ribonucleic acid and POMC-derived peptides in human peripheral blood mononuclear cells: no evidence for a lymphocyte-derived POMC system
Humans; Molecular Sequence Data; Biomarkers of Pain; RNA; Base Sequence; beta-Endorphin/analysis; Biomarkers Reference List; Leukocytes; Lymphocytes/metabolism; Polymerase Chain Reaction; Chromatography; High Pressure Liquid; Pro-Opiomelanocortin/genetics; Mononuclear/metabolism; Blotting; Cathepsin D/metabolism; DNA Probes; Gel; Messenger/blood; Northern; Peptide Fragments/analysis; Peptide Mapping; Southern
A number of recent studies suggest that cells of the immune system, e.g. peripheral blood mononuclear cells (PBMC), can synthesize and process POMC and secrete POMC-derived peptides, such as ACTH and endorphins, upon immune and hormonal challenges. From this, it has been proposed that POMC-derived peptides originating from lymphoid cells can function as hormones, for instance in a lymphoid-adrenal axis. In view of the important physiological implications of this proposal, the present study was designed to investigate the expression of the POMC gene in human PBMC and the production by these cells of alpha-, beta-, and gamma-endorphins (alpha E, beta E, and gamma E) peptides that are established end products of the posttranslational processing of POMC. PBMC of individual donors were used uncultured (fresh cells) or cultured for 24 and 48 h in the presence and absence of Concanavalin-A (Con-A), bacterial lipopolysaccharide, phytohemagglutinin, or CRH, and vasopressin, conditions that reportedly stimulate POMC activity in those cells, to investigate the presence of POMC transcripts by analysis of total RNA with Northern blotting and the reverse transcriptase polymerase chain reaction (RT-PCR). Large scale preparations containing over 10(9) cells (fresh, cultured with and without Con-A) originating from several donors were examined for the presence of POMC transcripts by analysis of poly(A)+ RNA on Northern blots and for the presence of alpha E, beta E, and gamma E by gel filtration over Sephadex G-75 and reverse phase HPLC, followed by assay of the fractions in four endorphin RIA systems with different specificities. On the Northern blots of total RNA, no POMC transcripts were detectable. In poly(A)+ RNA preparations, no full-length POMC mRNA was found, and it was estimated that the concentration of POMC mRNA, if present, was below approximately 0.005 transcript/cell in Con-A-stimulated cells and still lower in unstimulated cells. In accord with literature data, an 800- to 900-nucleotide POMC transcript was detected in cultured PBMC, and the levels of this transcript were stimulated by Con-A. In all samples analyzed with RT-PCR, a transcript spanning most of exons 2 and 3 was detectable only on Southern blots of the RT-PCR product, but not on agarose gels stained with ethidium bromide. Chromatographic analysis of endorphin immunoreactivities in cell extracts revealed no qualitative differences between the immunoreactive profiles of fresh PBMC or PBMC cultured with or without Con-A.(ABSTRACT TRUNCATED AT 400 WORDS)
1993
van Woudenberg AD; Metzelaar MJ; van der Kleij AA; de Wied D; Burbach JP; Wiegant VM
Endocrinology
1993
Article information provided for research and reference use only. PedPalASCNET does not hold any rights over the resource listed here. All rights are retained by the journal listed under publisher and/or the creator(s).
Journal Article
<a href="http://doi.org/10.1210/endo.133.5.8404638" target="_blank" rel="noreferrer">10.1210/endo.133.5.8404638</a>
Decreased levels of beta-endorphin in circulating mononuclear leukocytes from patients with acute myocardial infarction
Female; Humans; Male; Middle Aged; Biomarkers of Pain; Biomarkers Reference List; Leukocytes; beta-Endorphin/blood/immunology; Myocardial Infarction/blood; C-Reactive Protein/analysis; Mononuclear/metabolism
Lymphocytes can be activated to produce and release opioid peptides. We investigated the levels of immunoreactive beta-endorphin in peripheral blood mononuclear cells from 11 patients with acute myocardial infarction. The concentrations of beta-endorphin in mononuclear leukocytes of 30.2 +/- 6.9 pg/10(6) cells on admission were in the normal range of 20-40 pg/10(6) cells and decreased significantly to 6.9 +/- 1.9 pg/10(6) cells after 48 h (p < 0.05). Decreased levels of mononuclear leukocyte-associated beta-endorphin in acute myocardial infarction may be due to the release of endogenous opioid after stimulation by stress and acute-phase reactants and play a role in inflammation and pain.
1998
Buratti T; Schratzberger P; Dunzendorfer S; Manfreda SE; Pechlaner C; Joannidis M; Sacerdote P; Panerai AE; Wiedermann CJ
Cardiology
1998
Article information provided for research and reference use only. PedPalASCNET does not hold any rights over the resource listed here. All rights are retained by the journal listed under publisher and/or the creator(s).
Journal Article
<a href="http://doi.org/10.1159/000006815" target="_blank" rel="noreferrer">10.1159/000006815</a>