Platelet Serotonin Concentration Is Associated with Illness Duration in Schizophrenia and Chronological Age in Depression

Periconceptional Non-medical Maternal Determinants Influence the Tryptophan Metabolism: The Rotterdam Periconceptional Cohort (Predict Study)

Background

The vital role of the maternal tryptophan (TRP) metabolism in maternal health and pregnancy is well established. However, non-medical maternal determinants influencing the TRP metabolism have been poorly investigated. We hypothesise that periconceptional maternal non-medical determinants alter the TRP metabolism, affecting both kynurenine (KP) and serotonin pathway (SP) metabolite concentrations. Therefore, we investigated the influence of non-medical maternal determinants on the TRP metabolism during the periconception period.

Methods

About 1916 pregnancies were included from the Rotterdam Periconceptional Cohort between November 2010 and December 2020. Data on periconceptional non-medical maternal determinants were collected through questionnaires. Serum samples were collected at 8.5 (SD = 1.6) weeks of gestation and TRP, kynurenine (KYN), 5-hydroxytryptophan (5-HTP), 5-HT (5-hydroxytryptamine) and 5-hydroxyindole acetic acid (5-HIAA) were determined using validated liquid chromatography (tandem) mass spectrometry. Mixed models were used to determine associations between periconceptional non-medical maternal determinants and these metabolites.

Results

In total 11 periconceptional non-medical maternal determinants were identified. Protein intake was positively associated with TRP (β = .12, 95% CI = 0.07-0.17), while age, energy intake and body mass index (BMI) (β = -.24, 95% CI = -0.37 to -0.10) were negatively associated with TRP. Age, BMI and total homocysteine were associated with higher KYN, whereas non-western geographical origin was associated with lower KYN (β = -.09, 95% CI = -0.16 to -0.03). Protein intake and total homocysteine (β = .07, 95% CI = 0.03-0.11) had a positive association with 5-HTP, while a negative association was found for energy intake. A non-western geographical origin and drug use were associated with higher 5-HT, and BMI with lower 5-HT (β = -6.32, 95% CI = -10.26 to -2.38). Age was positively associated with 5-HIAA (β = .92, 95% CI = 0.29-1.56), and BMI negatively.

Conclusions

Periconceptional non-medical maternal determinants, including age, geographical origin, drug use, energy and protein intake, BMI and total homocysteine, influence KP and SP metabolite concentrations.

Mean platelet volume, platelet count, and neutrophil/lymphocyte ratio in drug-naïve patients with schizophrenia: a cross-sectional study

Introduction

Mean platelet volume (MPV), platelet count, and neutrophil/lymphocyte ratio (NLR) have been proposed to be biomarkers of the chronic inflammatory process in schizophrenia and indicative of increased cardiovascular risk.

Objective

To describe MPV, total platelet count (PLT), and NLR between healthy controls and patients with schizophrenia to determine the correlation between these parameters and the duration of untreated psychosis (DUP).

Methods

In a retrospective cross-sectional study, we included 175 patients with schizophrenia who had never received psychiatric treatment, and who had undergone blood biometry and blood chemistry within 24 h of admission. Laboratory studies were determined by the impedance method on Coulter ac-T 5 diff hematological equipment.

Results

Mean platelet volume levels in patients with schizophrenia were higher than in healthy controls but not statistically significant. The receiver operating characteristic curve for this parameter shows that the optimal cutoff point of agreement was 8.95 fL, with sensitivity and specificity for schizophrenia of 52% and 67%, respectively, and the area under the curve (AUC) was 0.580 (p = 0.079). DUP had no significant correlation with the blood parameters analyzed.

Conclusion

The results partially support the hypothesis that MPV, platelet count, and NLR is related to schizophrenia, and further research is needed to establish whether there is an underlying chronic inflammatory process.

Relation Between Unconjugated Bilirubin and Peripheral Biomarkers of Inflammation Derived From Complete Blood Counts in Patients With Acute Stage of Schizophrenia

BACKGROUND

Inflammation and oxidative stress are the major leading hypothetical causes of schizophrenia. Unconjugated bilirubin (UCB) is an efficient endogenous plasma antioxidant. Inflammation is closely linked to oxidative stress. The relationship between UCB and inflammatory markers should be paid close attention in schizophrenia acute stage. In this paper, combined UCB and inflammatory markers were evaluated for their capability in predicting schizophrenia in the acute stage to find an easy and effective indicator to identify acute schizophrenia.

METHODS

A total of 6,937 acute schizophrenia patients and 6,404 healthy controls (HCs) were enrolled. UCB and peripheral biomarkers of inflammation derived from complete blood counts (CBC) were investigated in the subjects with acute schizophrenia, and the results were compared with HCs. Simultaneously, Spearman test was employed to assess the correlation between the variables, while logistic regression was adopted to determine the combined equation and receiver operating characteristic curve was used to evaluate the combined value of UCB and peripheral biomarkers of inflammation derived from CBC to predict schizophrenia in the acute stage.

RESULTS

The study indicates that white blood cells, neutrophil, monocyte, mean platelet volume (MPV), red cell distribution width (RDW), neutrophil/lymphocyte ratio (NLR), and monocyte/lymphocyte ratio (MLR) have significantly increased in schizophrenia (p < 0.05 for all), while platelet, lymphocyte, and platelet/lymphocyte ratio (PLR) in schizophrenia have significantly decreased (p < 0.05 for all). UCB exhibits negative correlation with MPV significantly (r = 0.121, p < 0.001), and no correlation with neutrophil and monocyte. The correlations between UCB and other peripheral biomarkers of inflammation derived from CBC are very weak. MPV, RDW, NLR, MLR, PLR, and UCB were taken as independent variables for a logistic regression analysis. The model was as follows: Logit  ( P 1 ) = - 6 . 141 + 0 . 827  MPV + 5 . 613  MLR - 0 . 005  PLR - 0 . 346  UBC . The combination demonstrates better effectiveness in predicting schizophrenia in the acute stage (AUC 0.831, 95% CI 0.825 to 0.837).

CONCLUSION

UCB has a protective effect on acute stage of schizophrenia, which is weak and indirect by affecting the proinflammatory processes. Our findings suggest that a combination of MLR, MPV, PLR, and UBC could be used to predict acute stage of schizophrenia.

Alcohol-related phenotypes and platelet serotonin concentration

Alcohol dependence is a chronic relapsing mental disorder with heterogeneous and complex underlying biology. It is frequently associated with nicotine dependence, severity of alcohol dependence symptoms, and diverse alcohol-related phenotypes, including the presence of delirium tremens and withdrawal symptoms, early or late onset of alcohol abuse, aggression, suicidal behavior, and anxiety. While searching for peripheral biomarkers of altered serotonergic (5-HT) function in alcohol dependence and alcohol-related behaviors, we determined a peripheral biomarker, i.e., platelet 5-HT concentration in a large group of Caucasian subjects with alcohol dependence subdivided according to the presence of specific alcohol-related phenotypes and smoking status. Individuals with alcohol dependence (n = 661) of both sexes were evaluated using Structural Clinical Interview based on DSM-IV criteria, while platelet 5-HT concentration was determined using the spectrophotofluorimetric method. Smoking is significantly associated, while sex and age are not, with platelet 5-HT concentration. Severe alcohol dependence and lack of withdrawal symptoms were associated with significantly decreased platelet 5-HT concentration in alcohol-dependent non-smokers. In smokers, significantly lower platelet 5-HT concentration was found in patients with the late onset of alcohol abuse. These results suggested that platelet 5-HT concentration might be used as a peripheral marker of different alcohol-related phenotypes, after controlling for the effects of smoking and sex.