The LPS‐induced increase in circulating microparticles is not affected by vitamin C in humans. (18th April 2013)

• Record Type: Journal Article
• Authors: Weisshaar, Stefan; Gouya, Ghazaleh; Nguyen, Daniel; Kapiotis, Stylianos; Wolzt, Michael
• Is Part Of: European journal of clinical investigation. Volume 43:Number 7(2013:Jul.)
• Page Start: 708
• Page End: 715
• Publication Date: 2013-04-18
• Subjects: Pathology -- Periodicals; Medical research -- Periodicals; 616.075
• DOI: 10.1111/eci.12096
• Languages: English
• ISSNs: 0014-2972

Abstract

<abstract abstract-type="main" xml:lang="en" id="eci12096-abs-0001"> <title>Abstract</title> <sec id="eci12096-sec-0001" sec-type="section"> <title>Objective</title> <p>Microparticles (MP) are considered to promote coagulation. This study aimed to characterize the time course of MP levels and the effect of high‐dose vitamin C on MP formation during inflammation in an <italic>in vivo Escherichia coli</italic> endotoxin (LPS) model.</p> </sec> <sec id="eci12096-sec-0002" sec-type="section"> <title>Methods</title> <p>Microparticle formation was studied in 14 male subjects in a cross‐over trial who received either intravenous vitamin C at 320 mg/kg body weight (BW) or 480 mg/kg BW or saline solution in a random order on alternate trial days 3 h after intravenous exposure to LPS (2 ng/kg BW). Venous blood samples were taken before, 3 and 6 h after LPS. D‐dimer, leucocyte count, C‐reactive protein, plasma vitamin C and body temperature were assessed as inflammatory parameters. MP were detected using flow cytometric analysis and expressed in 10³ MP/mL plasma.</p> </sec> <sec id="eci12096-sec-0003" sec-type="section"> <title>Results</title> <p>Microparticles levels were decreased from baseline 848 units [range 431–1705] by 21% to 671 units [253–1586] at 3 h and increased by 32% to 1119 units [288–4443] at 6 h after LPS. This pattern was not influenced by administration of vitamin C, with a change from 730 units [399–1396] at baseline by an increase to 832 units [215–2168] at 3 h to 1055 units [350–4858] at 6 h. MP subpopulations followed similar dynamics. Alterations in inflammatory parameters were independent from vitamin C administration during endotoxemia.</p> </sec> <sec id="eci12096-sec-0004" sec-type="section"> <title>Conclusion</title> <p>Microparticles are increased in acute systemic inflammation with inconsistent changes in MP subgroups in healthy subjects. Systemic vitamin C administration does not mitigate MP formation and D‐dimer levels during acute systemic inflammation, suggesting that MP‐induced coagulation activity is not affected by vitamin C.</p> </sec> </abstract>