Platelet-rich Plasma Serotonin Research Articles

Evaluation of serotonin levels in full-term newborns of diabetic mothers

BACKGROUND: The growth of neurological and mental diseases in the offspring of patients with pre- and gestational diabetes mellitus determines the need to study the regulatory function of the serotoninergic system of the brain in newborns. This plays a key role in its morphofunctional development in early ontogenesis, which is necessary for timely diagnosis of disorders and prevention of long-term consequences.
 AIM: The aim of this study was to evaluate serotonin levels in full-term newborns with diabetic fetopathy from mothers with pre- and gestational diabetes mellitus.
 MATERIALS AND METHODS: The main group consisted of 45 newborns with diabetic fetopathy, of whom 30 individuals were from mothers with type 1 diabetes mellitus and 15 ones from mothers with gestational diabetes mellitus. The control group comprised 20 healthy full-term newborns from healthy mothers without pregnancy complications. Serotonin concentrations were determined in platelet-rich plasma of blood from the umbilical cord vein, and in a platelet suspension prepared from venous blood taken on the first day of life, using high-performance liquid chromatography with electrochemical detection.
 RESULTS: Platelet-rich plasma serotonin level in umbilical cord blood taken from newborns of the main group was more than two times lower compared to children of healthy mothers. This parameter in venous blood taken from mothers with type 1 diabetes (0.744 ± 0.117 µmol/l) corresponded to that in healthy patients, while in mothers with gestational diabetes mellitus, it was significantly lower and amounted to 0.331 ± 0.071 µmol/l (p 0.05). Moreover, platelet-rich plasma serotonin level in all newborns correlated with that in their mothers (R = 0.505; p 0.05). Serotonin levels in venous blood platelets of newborns of the main group was almost 2.5 times lower than in healthy ones.
 CONCLUSIONS: The data obtained indicate the need to use platelet serotonin values as a biochemical marker of disorders of functional brain development in children with diabetic fetopathy.

Serotonin and cyclic sleep organization in full-term newborn infants with intrauterine growth retardation

BACKGROUND: The high frequency of neurological and mental diseases in children who had intrauterine retardatiojn development indicates the need to study specific markers of disorders of fetal brain functional development, in particular, the state of the serotonergic system, which plays a key role in the morpho-functional development of the brain in early ontogenesis.
 AIM: To study the content of serotonin in full-term newborns with intrauterine development delay in comparison with quantitative and qualitative characteristics of sleep.
 MATERIALS AND MЕTHODS: The main group consisted of 26 newborns, whose intrauterine development took place in conditions of chronic placental insufficiency, which led to the formation of an asymmetric form of intrauterine retardatiojn development. The control group consisted of 72 healthy newborns from healthy mothers without pregnancy complications. Children of each group are divided into three subgroups depending on gestational age: I 37, II 38, III 3940 weeks. In all children, 712 hours after birth, an electropoligram of sleep was recorded (an electroencephalograph of the company Mizar, Russia) and its quantitative and qualitative analyses were carried out, highlighting the orthodox, paradoxical phase and undifferentiated state. The serotonin content was determined in platelet-rich plasma of blood from the umbilical cord vein after birth, as well as in a platelet suspension prepared from venous blood taken on the first day of life. The content of serotonin in platelets was judged by the indicator obtained by dividing the amount of serotonin in the platelet suspension by the platelet level. The amount of serotonin was determined by high-performance liquid chromatography with electrochemical detection. Statistical analysis was performed using the Statistica 6 program (Statsoft Inc, USA).
 RESULTS: We report here a low content of serotonin in platelet-rich plasma and platelets of newborns with intrauterine growth retardation and the absence of its normal increase in weeks 3739 of intrauterine development, as well as a violation of the genetic programming for the sleep-wake cycle organization.
 CONCLUSIONS: Assessment of the serotonin-producing system of the brain in comparison with the newborn sleep pattern can serve as a diagnostic marker of brain damage and substantiate the need for timely application of neuroprotection.

Serotonin and cyclic sleep organization in healthy full-term newborns

Relevance: The growth of neuropsychiatric diseases caused by perinatal pathology indicates the need to study the biochemical markers of brain damage in the newborn for the timely prevention of adverse consequences. Serotonin in early ontogenesis provides intensive development of neuronal structures and cortical networks involved in the mechanisms of formation of cyclic sleep organization a fine criterion of morphofunctional development of the brain.
 aim: The aim of the work is to study the content of serotonin in healthy full-term newborns in comparison with the quantitative and qualitative characteristics of the electropoligraphic sleep pattern.
 Material and methods: 84 healthy newborns were examined, which, depending on the gestational age, were divided into 3 groups: I 37 weeks (20 people), II 38 weeks (24 people), III 39-40 weeks (40 people). The content of serotonin in platelet-rich plasma of blood from the umbilical cord vein and in platelet suspension prepared from venous blood taken from mothers and children on the first day of life and again on day 5 was determined by high-performance liquid chromatography with electrochemical detection. A quantitative and qualitative analysis of the sleep electropoligram was performed 7-12 hours after birth.
 Results: The content of serotonin in platelet-rich plasma in umbilical cord blood in children does not depend on the method of birth, is 2 times lower than in the venous blood of mothers (0.379 0.116 microns/l, versus 0.756 0.200 microns/l, but there is a high correlation between the indicators (r = 0.8, p 0.05). At the gestational age of 39-40 weeks, the level of serotonin in platelet-rich plasma and in venous blood platelets is significantly higher than in those born at 37 weeks. In the latter, the increase in the content of serotonin in platelets continues after birth (at day 1, 0.539 0.149 nM/109 Tr, and on day 5 0.846 0.094 nM/109 Tr; p 0.05), whereas the indicators for those born at 39-40 weeks of pregnancy. They do not change (0.797 0.190 nM/109 Tr and 0.749 0.142 nM/109 Tr, respectively). A significant increase in the content of serotonin in the platelet-rich plasma and in the platelets of the child in the period from 37 to 39 weeks, both during intrauterine development and in the first days of life, correlates with an increase in the representation of the orthodox phase in the sleep cycle.
 Conclusion: The general pattern of changes in serotonin content and cyclic sleep organization in the early neonatal period in healthy newborns, depending on gestational age, indicates the possibility of using the obtained standard values of serotonin as a biochemical marker of functional brain development.

Defective acid hydrolase secretion in RUNX1 haplodeficiency: Evidence for a global platelet secretory defect.

RUNX1 haplodeficiency is associated with thrombocytopenia, platelet dysfunction and a predisposition to acute leukaemia. Platelets possess three distinct types of granules and secretory processes involving dense granules (DG), α-granules and vesicles or lysosomes containing acid hydrolases (AH). Dense granules and granule deficiencies have been reported in patients with RUNX1 mutations. Little is known regarding the secretion from AH-containing vesicles. We studied two related patients with a RUNX1 mutation, easy bruising, and mild thrombocytopenia. Platelet aggregation and 14 C serotonin in platelet-rich plasma (PRP) were impaired in response to ADP, epinephrine, collagen and arachidonic acid. Contents of DG (ATP, ADP), α-granules (β-thromboglobulin) and AH-containing vesicles (β-glucuronidase, β-hexosaminidase, α-mannosidase) were normal or minimally decreased. Dense granules secretion on stimulation of gel-filtered platelets with thrombin and divalent ionophore A23187 (4-12μmol L-1 ) were diminished. β-thromboglobulin and AH secretion was impaired in response to thrombin or A23187. We studied thromboxane-related pathways. The incorporation of 14 C -arachidonic acid into phospholipids and subsequent arachidonic acid release on thrombin activation was normal. Platelet thromboxane A2 production in whole blood serum and on thrombin stimulation of PRP was normal, suggesting that the defective secretion was not due to impaired thromboxane production. These studies provide the first evidence in patients with a RUNX1 mutation for a defect in AH (lysosomal) secretion, and for a global defect in secretion involving all three types of platelet granules that is unrelated to a granule content deficiency. They highlight the pleiotropic effects and multiple platelet defects associated with RUNX1 mutations.

A serum and platelet-rich plasma serotonin assay using liquid chromatography tandem mass spectrometry for monitoring of neuroendocrine tumor patients

BackgroundSerotonin is used for the diagnosis and follow-up of neuroendocrine tumors (NET). We describe the analytical and clinical validation of a liquid chromatography tandem mass spectrometry (LC-MS/MS) based serotonin assay for serum and platelet-rich plasma (PRP). MethodsAn LC-MS/MS based method for serum and PRP serotonin was validated by determination of assay imprecision, carry-over, linearity, interference, recovery, sample stability and a matrix/method comparison of serum and PRP serotonin was made with whole blood serotonin. Furthermore, upper limits of normal were determined and serotonin concentrations of healthy individuals, 14 NET patients without evidence of disease and 51 NET patients with evidence of disease were compared. ResultsFor serum and PRP fractions, total assay imprecision was <5%. All correlation coefficients were 0.98 and the serum and platelet-rich serotonin upper limit of normal were 5.5nmol/109 platelet and 5.1nmol/109 platelet, respectively. NET patients with confirmed evidence of disease had significantly higher serum and PRP serotonin levels when compared to NET patients without evidence of disease and healthy volunteers. ConclusionsLC-MS/MS based serum and PRP serotonin assays were developed with suitable analytical characteristics. Furthermore, serum and PRP serotonin was found to be useful for monitoring NET patients.

Endophenotypes and serotonergic polymorphisms associated with treatment response in obsessive-compulsive disorder

OBJECTIVES:Approximately 40-60% of obsessive-compulsive disorder patients are nonresponsive to serotonin reuptake inhibitors. Genetic markers associated with treatment response remain largely unknown. We aimed (1) to investigate a possible association of serotonergic polymorphisms in obsessive-compulsive disorder patients and therapeutic response to selective serotonin reuptake inhibitors and (2) to examine the relationship between these polymorphisms and endocrine response to intravenous citalopram challenge in responders and non-responders to serotonin reuptake inhibitors and in healthy volunteers.METHODS:Patients with obsessive-compulsive disorder were classified as either responders or non-responders after long-term treatment with serotonin reuptake inhibitors, and both groups were compared with a control group of healthy volunteers. The investigated genetic markers were the G861C polymorphism of the serotonin receptor 1Dβ gene and the T102C and C516T polymorphisms of the serotonin receptor subtype 2A gene.RESULTS:The T allele of the serotonin receptor subtype 2A T102C polymorphism was more frequent among obsessive-compulsive disorder patients (responders and non-responders) than in the controls (p<0.01). The CC genotype of the serotonin receptor subtype 2A C516T polymorphism was more frequent among the non-responders than in the responders (p<0.01). The CC genotype of the serotonin receptor subtype 1Dβ G681C polymorphism was associated with higher cortisol and prolactin responses to citalopram (p<0.01 and p<0.001, respectively) and with a higher platelet-rich plasma serotonin concentration among the controls (p<0.05). However, this pattern was not observed in the non-responders with the same CC genotype after chronic treatment with serotonin reuptake inhibitors. This CC homozygosity was not observed in the responders.

HPLC Determination of Serotonin and Its Metabolites From Human Platelet-Rich Plasma; Shift to 5-Hydroxytryptophol Formation Following Alcohol Consumption

A sensitive, simple, and reliable high-performance liquid chromatographic method with electrochemical detection is developed for the measurement of four natural products, the serotonin-related indols from human platelet-rich plasma (PRP) using N-methylserotonin as internal standard. Separation of serotonin (5HT), 5-hydroxytryptophan (5HTP), 5-hydroxytryptophol (5HTOL), and 5-hydroxyindole-acetic acid (5HIAA) is carried out on Supelcosil LC-18DB stationary phase. A mixture of 48 mM citric acid, 28 mM sodium phosphate dibasic, 0.027 mM Na2EDTA, and 3% methanol (pH 3.18) serves as the mobile phase. Measurements are carried out at 25 degrees C at Eox=0.65 V. The calibration curves are linear through the range of 10-200 pg/mL. Method validation is performed according to internationally accepted criteria. Blood is collected from healthy controls and schizophrenic subjects. Significantly higher PRP serotonin is measured in schizophrenics; patients with recent alcohol consumption could be characterized with significantly elevated 5HTOL/5HIAA ratio.

Comparison of Platelet-Rich Plasma Serotonin Level and Quantitative Neutrophil PRV-1 Assay in Chronic Myeloproliferative Disorders.

In a prospective study of 100 subjects, an ELISA assay was used to measure platelet-rich plasma (PRP) serotonin levels in patients with polycythemia vera (PV; n=26), essential thrombocythemia (ET; n=14), myelofibrosis with myeloid metaplasia (MMM; n=26), secondary or spurious polycythemia (SP; n=20) and controls (n=14). Neutrophil PRV-1 expression was concurrently assayed by real-time PCR in 69 patients (23 PV, 17 SP, 12 ET, 7 MMM, 10 controls). Table 1 outlines the median and range of measured values across the different study groups.Table 1ControlsSPPVETMMMAge in yearsN/A49 (18–77)64 (32–83)52 (18–81)60 (22–80)Plt count x 109/LN/A249 (157–371)509 (191–940)613 (284–1100)259 (64–955)PRP serotonin; ng/109 plts567 (360–1071)609 (369–1780)205 (0–496)385 (137–1026)90 (0–278)PRV-1/GAPDH ratio1.28 (1.20–1.43)1.23 (1.13–1.38)1.03 (0.84–1.28)1.24 (0.99–1.44)1.25 (1.11–1.40)A highly significant difference (p < 0.0001), in PRP serotonin levels, was seen among the different disease categories and control group (table 1). The lowest levels were registered for MMM and PV with a statistically significant difference between the two groups (p = 0.015) but a large degree of overlap. The results in both were significantly as well as markedly lower than those of controls as well as SP with only slight overlap in the PV group and no overlap in the MMM group (p < 0.0001; table 1). The PRP serotonin levels in patients with ET were significantly reduced compared to both controls (p = 0.019) and SP (p = 0.002) and significantly increased compared to both PV (p = 0.0008) and MMM (p < 0.0001). However, there was a substantial degree of overlap in values between ET and other disease categories and controls. Neither aspirin nor cytoreductive therapy correlated with PRP serotonin levels (p = 0.116 and p = 0.148, respectively). Similarly, within a specific disease category, PRP serotonin level did not significantly correlate with platelet count, hemoglobin level, leukocyte count, spleen size, disease duration, or gender. However, an inverse correlation with age was noted only in MMM. In general, there was not a significant correlation between PRP serotonin level and neutrophil PRV-1 expression in each of the three myeloproliferative disease variants. Tests of sensitivity, specificity, and accuracy in distinguishing PV from SP were 92, 95, and 93% for the PRP serotonin assay and 78, 95, 86% for neutrophil PRV-1 assay, respectively. The current study suggests that PRP serotonin concentration might be considered as one of several biological markers that complement each other for the diagnosis of PV.

An open-label dosing study of paroxetine in depressed children and adolescents

Background: Depression is a common disorder in children and adolescents. It is often associated with psychologic distress, academic dysfunction, intrafamilial conflict, and the risk for suicide. For these reasons, safe and effective treatments are needed for depression in pediatric patients. Objective: This study considered the effectiveness of initiating the antidepressant paroxetine at a low dose and explored clinical and biochemical factors associated with response in juvenile depression. Methods: In this 8-week, single-center, open-label trial, children and adolescents with major depression were assessed weekly. Patients were initially treated with paroxetine at a dosage of 10 mg/d for 4 weeks. If a priori criteria for improvement were not met, the dosage of paroxetine was increased to 20 mg/d. Standard psychometric outcome measures were used. Prior to treatment, patients' phenotypes for cytochrome P450 2D6 and catechol O-methyltransferase activity were determined. Platelet-rich plasma serotonin was measured before and after 4 weeks of therapy. Plasma paroxetine concentration was measured after 4 weeks of treatment. Results: Thirty children and adolescents (15 boys, 15 girls) aged 6 to 17 years were enrolled and 29 were treated. Of the 27 patients who received at least 4 weeks of paroxetine treatment, 18 (66.7%) met improvement criteria at week 4. Open-label paroxetine was generally well tolerated and was associated with significant symptom amelioration by week 8 for most patients. Age, other demographic characteristics, and biochemical variables did not differ between the patients who had their dose of paroxetine increased and those who did not. Conclusions: The results of this study suggest that paroxetine 10 mg/d is effective in the open-label treatment of most depressed children and adolescents. For those who do not respond to this dosage, an increase to 20 mg/d appears to be an empirically supported treatment strategy.

Profiling of Tryptophan-related Plasma Indoles in Patients with Carcinoid Tumors by Automated, On-Line, Solid-Phase Extraction and HPLC with Fluorescence Detection

Profiling of the plasma indoles tryptophan, 5-hydroxytryptophan (5-HTP), serotonin, and 5-hydroxyindoleacetic acid (5-HIAA) is useful in the diagnosis and follow-up of patients with carcinoid tumors. We describe an automated method for the profiling of these indoles in protein-containing matrices as well as the plasma indole concentrations in healthy controls and patients with carcinoid tumors. Plasma, cerebrospinal fluid, and tissue homogenates were prepurified by automated on-line solid-phase extraction (SPE) in Hysphere Resin SH SPE cartridges containing strong hydrophobic polystyrene resin. Analytes were eluted from the SPE cartridge by column switching. Subsequent separation and detection were performed by reversed-phase HPLC combined with fluorometric detection in a total cycle time of 20 min. We obtained samples from 14 healthy controls and 17 patients with metastasized midgut carcinoid tumors for plasma indole analysis. In the patient group, urinary excretion of 5-HIAA and serotonin was compared with concentrations of plasma indoles. Within- and between-series CVs for indoles in platelet-rich plasma were 0.6-6.2% and 3.7-12%, respectively. Results for platelet-rich plasma serotonin compared favorably with those obtained by single-component analysis. Plasma 5-HIAA, but not 5-HTP was detectable in 8 of 17 patients with carcinoid tumors. In the patient group, platelet-rich plasma total tryptophan correlated negatively with platelet-rich plasma serotonin (P = 0.021; r = -0.56), urinary 5-HIAA (P = 0.003; r = -0.68), and urinary serotonin (P <0.0001; r = -0.80). The present chromatographic approach reduces analytical variation and time needed for analysis and gives more detailed information about metabolic deviations in indole metabolism than do manual, single-component analyses.

Impaired Platelet Binding of Fibrinogen Due to a Lower Number of GPIIB/IIIA Receptors in Polycythemia Vera

We have previously described a stimulus-specific defect in platelet aggregation in polycythaemia vera (PV) after stimulation with surface receptor dependent agonists such as platelet activating factor (PAF). In contrast, responses to phorbol myristate acetate (PMA) were normal. We now report that after PAF stimulation, using flow cytometry, the amount of fibrinogen bound to its receptor was significantly lower in PV platelets with a median MFI of 6.0 (range 4.1–17.3) compared to controls, 12.8 ( range 8–21.3; n=11; p<0.01 ). We found no evidence of preactivation of PV platelets. Quantitative analysis of GPIIIa gave a significantly lower number of GPIIIa on resting PV platelets, 14300 subunits of GPIIIa (range 8500–15500) vs. 19800 for controls ( range 13400–26800; n=12; p<0.01 ). Both patients and controls increased their number of receptors on the cell surface after stimulation with PAF and PMA, but the significant difference in the number of receptors per cell remained. Indirect evaluation of PAF receptor function showed that activation of CD 62 did not differ in PV and controls after PAF stimulation. Additionally, although the basal level of serotonin in platelet-rich plasma was significantly lower in PV, there was a threefold increase of the basal level after stimulation with PAF for both PV and control platelets, also indicating a normal interaction of PAF with its receptor. Although our results indicate both an impaired PAF induced aggregation in PV and a lower number of GPIIb/IIIa complexes on single platelets, whether these phenomena are related remains uncertain.

Improved method for the determination of serotonin in plasma by high-performance liquid chromatography using on-line sample pre-treatment

An improved method for the determination of serotonin in platelet-rich plasma (PRP) and platelet-poor plasma (PPP), by reversed-phase high-performance liquid chromatograpy with electrochemical detection and direct plasma injection, is described. The chromatographic system comprises a strong cation-exchange pre-column and a C 18 analytical column. The method is selective, rapid, simple and sensitive, and offers good reproducibility and recovery. Reference values for serotonin concentrations in healthy adults ( n = 10) are 31 n M for PPP and 6 nmol per 10 9 platelets for PRP. The conditions used for the preparation of PRP and PPP may influence the serotonin concentration in PRP.

Biochemical and functional abnormalities in hypercholesterolemic rabbit platelets

This study was designed to elucidate changes in rabbit platelet lipids induced by a cholesterol rich diet and to explore the possible correlation of these lipid changes with platelet abnormalities. Pronounced biochemical alterations were observed when serum cholesterol levels of 700-1000 mg% were reached. Hypercholesterolemic (HC) platelets contained 37% more neutral lipids and 16% less phospholipids than the controls. Lysolecithin, cholesterol esters and phosphatidylinositol (PI) levels were increased in HC platelets, and the levels of phosphatidylcholine (PC) were decreased. The cholesterol/phospholipid molar ratio of lipidemic platelets increased from 0.55 +/- 0.011 to 0.89 +/- 0.016 (P less than 0.01) in eight weeks. HC platelets had 90% more arachidonic acid (AA) in the PI than normal platelets. No significant changes in AA of PC were observed. Platelet function was monitored by the uptake and release of [14C]serotonin in platelet rich plasma (PRP), using varying concentrations of collagen as an aggregating agent. The uptake of [14C]serotonin in HC and normal platelets ranged from 78-94%. The percent of [14C]serotonin released from normal and HC platelets was proportional to the concentration of collagen. However, lipidemic platelets were hyperreactive to low concentrations of collagen. Incorporation of 50 microM acetylsalicylic acid into the aggregating medium suppressed the release of [14C]serotonin in normal PRP by more than 90%, but had only a partial effect on lipidemic PRP.

A follow-up study of platelet-rich plasma serotonin in clinical subtypes of cerebral infarction.

The serotonin concentration in the platelet-rich plasma of 32 patients with single and multiple stroke type cerebral infarction was investigated at various stages. Serotonin levels were decreased in the acute period. The incidence of serotonin abnormality was higher in multiple types than in the single type. Serotonin levels were significantly decreased in treated hypertensive patients compared with untreated patients. Serotonin levels, therefore, varied according to the type and stage of cerebral infarction.

Development and validation of an improved radioimmunoassay for serotonin in platelet-rich plasma

A radioimmunoassay (RIA) using a 125I-tracer is described for measurement of serotonin (5-hydroxytryptamine, 5-HT) in human platelet-rich plasma (PRP). Antisera were raised against 5-HT-succinamate conjugated to bovine albumin and, to improve assay sensitivity, the analyte was made chemically similar to the immunogen by conversion to N-acetylserotonin prior to assay, using the specific amino reagent N-acetoxysuccinimide. The assay shows good correlation with a high-pressure liquid chromatography (HPLC) reference method (5-HT RIA = 1.007 × 5HT HPLC + 29.3, r = 0.936, p < 0.001, n = 40), indicating that no significant cross-reactions were detected. Samples of PRP are diluted 1 20 to fall within the working range (80–15% B/ B o ) of the assay, which is 4.75–325 nmol/1, (0.95–65.0 pmol/ tube), corresponding to 95–6500 nmol/1 in PRP. Intra- and interassay coefficients of variation were 5.0–10.5% and 12.0–21.2% respectively for serotonin concentrations of 250–2500 nmol/l added to platelet-poor plasma. With this improved assay, it is possible to analyse up to 100 samples/ day, compared with 10–20 samples/ day by HPLC.

A spectrophotofluorimetric method for the determination of serotonin (5-hydroxytryptamine) in plasma

A method is presented for the determination of serotonin using a spectrophotofluorimeter. The method is suitable for platelet rich plasma and isolated platelet suspension. Serotonin is extracted from a protein free filtrate and the fluorescence measured in hydrochloric acid. Platelet rich plasma serotonin levels have been determined in 28 subjects.