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Involving 1 million people a year, suicide represents one of the major topics of psychiatric research. Despite the focus in recent years on neurobiological underpinnings, understanding and predicting suicide remains a challenge. Many sociodemographical risk factors and prognostic markers have been proposed but they have poor predictive accuracy. Biomarkers can provide essential information acting as predictive indicators, providing proof of treatment response and proposing potential targets while offering more assurance than psychological measures. In this framework, the aim of this study is to open the way in this field and evaluate the correlation between blood levels of serotonin, brain derived neurotrophic factor, tryptophan and its metabolites, IL-6 and homocysteine levels and suicidality. Blood samples were taken from 24 adults with autism, their first-degree relatives, and 24 controls. Biochemical parameters were measured with enzyme-linked immunosorbent assays. Suicidality was measured through selected items of the MOODS-SR. Here we confirm the link between suicidality and autism and provide more evidence regarding the association of suicidality with increased homocysteine (0.278) and IL-6 (0.487) levels and decreased tryptophan (−0.132) and kynurenic acid (−0.253) ones. Our results suggest a possible transnosographic association between these biochemical parameters and increased suicide risk.

Background: Several studies investigated circulating levels of serotonin (5-HT) and brain-derived neurotrophic factor (BDNF) in children with Autism spectrum disorder (ASD). More limited literature focused on ASD adults or on populations with subthreshold autism spectrum manifestations, such as relatives of ASD probands. This study aimed to investigate 5-HT and BDNF levels in adults with autism spectrum conditions. Correlations between levels of biochemical variables and ASD symptoms were also evaluated. Method: a sample of ASD adults, their first-degree relatives (Broad autism phenotype, BAP group), and controls were recruited and assessed with psychometric scales. Blood samples were collected from all participants. 5-HT and BDNF levels were measured by means of ELISA kits. Results: ASD adults showed significantly lower platelet-poor plasma (PPP) 5-HT levels than BAP and control groups. No significant difference was found among groups for PPP BDNF levels and intra-platelet 5-HT levels. 5-HT levels were reported to be specifically correlated with some autism symptoms. Conclusion: This work highlighted the presence in ASD adults of reduced PPP 5-HT levels than in other groups, without significant differences with respect to BDNF levels, supporting the hypothesis that biochemical correlates of ASD in adults may be different from those typically reported in children.

Mammal's saliva contains a variety of electrolytes and proteins. They carry out an important role in the digestion process, in the antibacterial and antiviral activity, in lubrication and maintenance of oral general health status. It may also contain several enzymes according to dietary habits and general wellness. Sialochemistry is a valid alternative to the haematochemical analysis for the evaluation of animal health and nutritional status. At present, very little knowledge is available on health status and pathology of crested porcupine (Hystrix cristata) and no data are yet available on salivary enzymes. Between 2018 and 2020, a preliminary investigation of enzymatic activity on saliva samples was carried out from captured porcupines. In crested porcupine saliva, enzymatic activity of trypsin, chymotrypsin, N-Aminopeptidase, amylase, lignin peroxidise, cellulase and chitinase were recorded. Superoxide dismutase, catalase, glutathione S-transferase and alkaline phosphatase activity was also detected. The superoxide dismutase activity resulted higher (3.13 SD 3.58 U/mg proteins) than those of catalase (130.80 SD 110.65 mU/mg proteins) and glutathione S-transferase (20.21 SD 16.62 mM/mg proteins). Alkaline phosphatase activity resulted lower (5.91 SD 6.12 mU/mg proteins) than acidic phosphatase (19.00 SD 16.16 U/mg proteins) with the highest values of saliva alkaline phosphatases recorded in young individuals. These preliminary data bring new knowledge on crested porcupine saliva enzymes and may provide a useful tool for further investigation on the adaptive response of crested porcupine to different environmental condition and diet. Additional investigation concerning a possible alternative use of saliva enzymes as indicator of health and nutritional status of this rodent are desirable.

Background Increasing literature highlighted alterations of tryptophan (TRP) metabolism and kynurenine (KYN) pathway in children with autism spectrum disorder (ASD). However, no study specifically focused on adult samples. Meanwhile, several authors stressed the relevance of investigating neurobiological correlates of adult forms of ASD and of those subthreshold ASD manifestations frequently found in relatives of ASD probands, known as broad autism phenotype (BAP). This work aimed to evaluate circulating levels of TRP and metabolites of KYN pathway in a sample of ASD adults, their first-degree relatives and controls (CTLs), investigating also the correlations between biochemical variables’ levels and ASD symptoms. Methods A sample of ASD adults, together with a group of first-degree relatives (BAP group) and unrelated CTLs were assessed by means of psychometric scales. Circulating levels of TRP, KYN, quinolinic acid (QA), and kynurenic acid (KYNA) were assessed in all subjects. Results ASD patients reported significantly higher total scores than the other groups on all psychometric scales. BAP subjects scored significantly higher than CTLs. ASD patients reported significantly lower TRP levels than BAP and CTL groups. Moreover, significantly lower levels of KYNA were reported in both ASD and BAP groups than in CTLs. Specific patterns of associations were found between autism symptoms and biochemical variables. Conclusions Our findings confirm in adult samples the presence of altered TRP metabolism through KYN pathway. The intermediate alterations reported among relatives of ASD patients further stress the presence of a continuum between subthreshold and full-threshold ASD phenotypes also from a biochemical perspective.

Several heterogeneous pathophysiology pathways have been hypothesized for being involved in the onset and course of Post-Traumatic Stress Disorder (PTSD). This systematic review aims to summarize the current evidence on the role of inflammation and immunological dysregulations in PTSD, investigating possible peripheral biomarkers linked to the neuroimmune response to stress. A total of 44 studies on the dysregulated inflammatory and metabolic response in subjects with PTSD with respect to controls were included. Eligibility criteria included full-text publications in the English language, human adult samples, studies involving both subjects with a clinical diagnosis of PTSD and a healthy control group. The research was focused on specific blood neuroimmune biomarkers, namely IL-1β, TNF-α, IL-6 and INF-γ, as well as on the potential harmful role of reduced antioxidant activity (involving catalase, superoxide dismutase and glutathione peroxidase). The possible role of the inflammatory-altered tryptophan metabolism was also explored. The results showed conflicting data on the role of pro-inflammatory cytokines in individuals with PTSD, and a lack of study regarding the other mediators investigated. The present research suggests the need for further studies in human samples to clarify the role of inflammation in the pathogenesis of PTSD, to define potential peripheral biomarkers.

ObjectiveTo provide evidence to the link between serotonin (5-HT), energy metabolism, and the human obese phenotype, the present study investigated the binding and function of the platelet 5-HT transporter (SERT), in relation to circulating insulin, leptin, and glycolipid metabolic parameters.MethodsSeventy-four drug-free subjects were recruited on the basis of divergent body mass index (BMIs) (16.5-54.8 Kg/m2). All subjects were tested for their blood glycolipid profile together with platelet [3H]-paroxetine ([3H]-Par) binding and [3H]-5-HT reuptake measurements from April 1st to June 30th, 2019.ResultsThe [3H]-Par Bmax (fmol/mg proteins) was progressively reduced with increasing BMIs (P Bmax was negatively correlated with BMI, waist/hip circumferences (W/HC), triglycerides (TD), glucose, insulin, and leptin, while positively with high-density lipoprotein (HDL) cholesterol (P Vmax, pmol/min/109 platelets) among BMI groups was not statistically significant, but Vmax negatively correlated with leptin and uptake affinity values (P 3H]-Par affinity values positively correlated with glycemia and TD, while [3H]-5-HT reuptake affinity with glycemia only (P P = .006) resulting negatively related to Bmax independently from BMI.ConclusionsPresent findings suggest the presence of a possible alteration of insulin/5-HT/leptin axis in obesity, differentially impinging the density, function, and/or affinity of the platelet SERT, as a result of complex appetite/reward-related interactions between the brain, gut, pancreatic islets, and adipose tissue. Furthermore, they support the foremost cooperation of peptides and 5-HT in maintaining energy homeostasis.

β-glucans can activate the animal innate immune system by acting as immune-modulators and inducing various stimulatory effects. The aim of this study was to investigate the effect of 1,3-1,6 β-glucans administered orally for 96 h on Apis mellifera workers (newly emerged and nurse bees). β-glucans were included in honey and syrup. Survival rate and phenoloxidase activity were measured. In both newly emerged and nurse bees, β-glucans supplementation did not affect survival rate (p > 0.05). Conversely, phenoloxidase activity was higher in both newly emerged bees (p = 0.048) and nurse bees (p = 0.014) fed with a honey diet enriched with β-glucans compared to those fed with only honey. In both the newly emerged and nurse bees, no statistical differences in phenoloxidase activity were recorded between the group fed with a syrup-based diet enriched with β-glucans and the control group (p > 0.05). The absence of significant variation in survival suggests that the potential negative effect of β-glucans in healthy bees could be mitigated by their metabolism. Conversely, the inclusion of β-glucans in a honey-based diet determined an increase of phenoloxidase activity, suggesting that the effect of β-glucan inclusion in the diet of healthy bees on phenoloxidase activity could be linked to the type of base-diet. Further investigations on β-glucans metabolism in bees, on molecular mechanism of phenoloxidase activation by 1,3-1,6 β-glucans, and relative thresholds are desirable. Moreover, investigation on the combined action of honey and β-glucans on phenoloxidase activity are needed.

Hydrolysable tannins are polyphenolic molecules contained in plant foodstuffs, potentially toxic for animals. Since tannins have been found in some bee products such as bee pollen, propolis, and ho...

Abstract:: Threats, challenging events, adverse experiences, predictable or unpredictable, namely stressors, characterize life, being unavoidable for humans. The hypothalamus-pituitary-adrenal axis (HPA) and the sympathetic nervous system (SNS) are well-known to underlie adaptation to psychosocial stress in the context of other interacting systems, signals and mediators. However, much more effort is necessary to elucidate these modulatory cues for a better understanding of how and why the "brain-body axis" acts for resilience or, on the contrary, cannot cope with stress from a biochemical and biological point of view. Indeed, failure to adapt increases the risk of developing and/or relapsing mental illnesses such as burnout, post-traumatic stress disorder (PTSD), and at least some types of depression, even favoring/worsening neurodegenerative and somatic comorbidities, especially in the elderly. We will review here the current knowledge on this area, focusing on works presenting the main brain centers responsible for stressor interpretation and processing, together with those underscoring the physiology/biochemistry of endogenous stress responses. Autonomic and HPA patterns, inflammatory cascades and energy/redox metabolic arrays will be presented as allostasis promoters, leading towards adaptation to psychosocial stress and homeostasis, but also as possible vulnerability factors for allostatic overload and non-adaptive reactions. Besides, the existence of allostasis buffering systems will be treated. Finally, we will suggest promising lines of future research, particularly the use of animal and cell culture models together with human studies by means of high-throughput multi-omics technologies, which could entangle the biochemical signature of resilience or stress-related illness, a considerably helpful facet for improving patients’ treatment and monitoring.

Temporal polyethism is based on physiological differences related to the honey bee activities into the colony, suggesting a different requirement of antioxidant activity in each honey bee developme...

Deficits in social-cognition processing have been identified during early stages of Huntington Disease (HD), attracting interest on their relevance as possible predictors of neurodegenerative progression. Since the neurotrophin Brain-Derived Neurotrophic Factor (BDNF) and the serotonin (5-HT) transporter (SERT) are known to modulate human adaptive behavior, we appraised these two proteins in mild-HD using blood platelets, with the aim at finding relationships with cognitive/psychosocial skills. Thirteen gene positive and symptomatic patients (9M/4W, HD-stage II, age> 40y) together 11 gender/age matched controls without a concurrent diagnosis of psychiatric disorders, underwent a blood test to determine BDNF storage and membrane-bound SERT in platelets by an ELISA immune-enzyme dosage and [ 3 H]-paroxetine ([ 3 H]-PAR) binding, respectively. Enrolled subjects were concurrently evaluated through a battery of socio-cognitive tests and emotion recognition questionnaires. Results showed greater intra-platelet BDNF (~ +20-22%) in patients versus controls, whereas equilibrium [ 3 H]-PAR binding parameters, maximum density (B max ) and dissociation constant (K D ), did not appreciably vary in the two comparison groups. Cognitive/emotion abilities were found significantly reduced in patients. Additionally, platelet BDNF was unrelated to psycho-cognitive scores, but positively correlated with the illness duration. As well, SERT B max was unconnected to HD signs or socio-cognitive scores, whilst K D s negatively correlated with scores for angry voice recognition in both controls and patients. This pilot study suggests that platelet BDNF and SERT do not specifically underlie psychosocial deficits in stage II-HD, while higher BDNF storage in delayed mild symptoms, would derive from compensatory mechanisms. Supplementary investigations are warranted, by also comparing patients in other illness’s phases.

Numerous pieces of evidence support the expression by the mammalian retina of Hydroxyindole-O-methyltransferase (HIOMT, EC 2.1.1.4), the enzyme directly responsible for the biosynthesis of the pineal chronobiotic hormone melatonin (MLT). However, conflicting results obtained so far by enzyme-kinetic and immune-detection techniques still make HIOMT presence and relevance in the eye a matter of debate. This work aimed at evaluating unambiguously HIOMT activity in the mouse retina, a valuable model for studying the effects of MLT variations on ocular pathophysiology. Since laboratory mouse strains can bear genetic polymorphisms yielding defective enzymes of MLT biosynthesis, retinas and control pineal glands used in this study were obtained in a MLT-proficient crossing of A/J mice, the A/J/C57BL/10 strain. To improve the radiochemical reference assay, we tested different homogenization procedures coupled with HPLC detection. Concomitantly, we quantified MLT, and its precursor N-acetyl-serotonin (NAS) by HPLC coupled to electrochemical detection in retinas isolated from either light- or dark-adapted mice. Results showed that the standard radio-chemical assay was successful for pineal HIOMT only, whereas specific homogenization buffers and HPLC were required to detect retinal activity, presumably due to interfering methyl-transferases inhibited by NAS. Under present conditions, retinal HIOMT Vmax accounted for by ≈ 40 fmol/h/mg protein, 2.6-hundreds-fold lower than the pineal counterpart, displaying equivalent KMs (≈10 μM). Moreover, NAS and MLT rapidly decreased in light-exposed isolated retinas, corroborating light-sensitive in-situ MLT formation. Conclusively, we measured mouse retinal HIOMT kinetics under basal conditions, a useful result to elucidate the regulatory patterns, the possible impact on eye health, and therapeutic approaches related to this enzyme.

Objectives: Ethnicity represents a crucial factor in influencing response to psychotropic drugs. Some data indicate that functional polymorphisms of two candidate genes of the serotonin (5-HT) tran...

Background:Autism Spectrum Disorder (ASD) is a condition strongly associated with genetic predisposition and familial aggregation. Among ASD patients, different levels of symptoms severity are detectable, while the presence of intermediate autism phenotypes in close relatives of ASD probands is also known in literature. Recently, increasing attention has been paid to environmental factors that might play a role in modulating the relationship between genomic risk and development and severity of ASD. Within this framework, an increasing body of evidence has stressed a possible role of both gut microbiota and inflammation in the pathophysiology of neurodevelopment. The aim of this paper is to review findings about the link between microbiota dysbiosis, inflammation and ASD.Methods:Articles ranging from 1990 to 2018 were identified on PUBMED and Google Scholar databases, with keyword combinations as: microbiota, immune system, inflammation, ASD, autism, broad autism phenotype, adult.Results:Recent evidence suggests that microbiota alterations, immune system and neurodevelopment may be deeply intertwined, shaping each other during early life. However, results from both animal models and human samples are still heterogeneous, while few studies focused on adult patients and ASD intermediate phenotypes.Conclusion:A better understanding of these pathways, within an integrative framework between central and peripheral systems, might not only shed more light on neural basis of ASD symptoms, clarifying brain pathophysiology, but it may also allow to develop new therapeutic strategies for these disorders, still poorly responsive to available treatments.

Numerous pieces of evidence support the expression by the mammalian retina of Hydroxyindole-O-methyltransferase (HIOMT, EC 2.1.1.4), the enzyme directly responsible for the biosynthesis of the pineal chronobiotic hormone melatonin (MLT). However, conflicting results obtained so far by enzyme-kinetic and immune-detection techniques still make HIOMT presence and relevance in the eye a matter of debate. This work aimed at evaluating unambiguously HIOMT activity in the mouse retina, a valuable model for studying the effects of MLT variations on ocular pathophysiology. Since laboratory mouse strains can bear genetic polymorphisms yielding defective enzymes of MLT biosynthesis, retinas and control pineal glands used in this study were obtained in a MLT-proficient crossing of A/J mice, the A/J/C57BL/10 strain. To improve the radiochemical reference assay, we tested different homogenization procedures coupled with HPLC detection. Concomitantly, we quantified MLT, and its precursor N-acetyl-serotonin (NAS) by HPLC coupled to electrochemical detection in retinas isolated from either light- or dark-adapted mice. Results showed that the standard radio-chemical assay was successful for pineal HIOMT only, whereas specific homogenization buffers and HPLC were required to detect retinal activity, presumably due to interfering methyl-transferases inhibited by NAS. Under present conditions, retinal HIOMT Vmax accounted for by ≈ 40 fmol/h/mg protein, 2.6-hundreds-fold lower than the pineal counterpart, displaying equivalent KMs (≈10 μM). Moreover, NAS and MLT rapidly decreased in light-exposed isolated retinas, corroborating light-sensitive in-situ MLT formation. Conclusively, we measured mouse retinal HIOMT kinetics under basal conditions, a useful result to elucidate the regulatory patterns, the possible impact on eye health, and therapeutic approaches related to this enzyme.

The aim of the present study was to appraise retrospectively the influence of valproate (VPA) and antidepressants (ADs) on the steady-state plasma concentrations of clozapine (CLZ), the prototype of various second-generation antipsychotics, norclozapine (NCLZ, its main metabolite), and their ratio (NCLZ:CLZ).Sixty-seven psychotic patients with a prevalent diagnosis of bipolar disorder were studied. We then analyzed data altogether and subdivided them into 4 groups, according to pharmacological treatments: #1 CLZ (n = 21), #2 CLZ plus ADs (n = 13), #3 CLZ plus VPA (n = 16), and #4 CLZ plus ADs plus VPA (n = 17).First, significant positive between CLZ and NCLZ plasma levels (in nanograms/milliliter) and the drug daily dosages (in milligrams/kilogram of body weight) (n = 67) were observed (Spearman: rCLZ = 0.49; rNCLZ = 0.61; P0.001). We then normalized by given doses CLZ and NCLZ plasma levels, natural log transformed them, and performed analysis of variance factor analyses followed by pairwise comparisons, performed on the 4 groups and the 3 CLZ parameters. We identified significant drug effects on (1) CLZ plasma levels, significantly higher in group #2 versus group #1, and (2) NCLZ:CLZ ratio, lower in group #2 versus groups #1 and #3. Significant drug × gender interactions were observed in group #3, showing higher NCLZ levels and NCLZ:CLZ ratios in men compared with women.Despite its inherent limitations, this observational study confirms the significant increase in plasma CLZ concentrations and reduction in NCLZ:CLZ ratio when this drug was coadministered with ADs (group #2), an effect apparently counteracted by VPA (group #4). The drug × gender interactions in patients taking both CLZ and VPA (group #3) warrant further prospective study.

This study is aimed at relating social cognition in Huntington&rsquo, s Disease (HD) to plasma levels of the social hormone oxytocin (OT). Indeed, HD patients commonly display reduced social skills and OT is involved in bonding behavior and improved recognition of facial emotions. Twelve mild-symptomatic HD patients (stage II Shoulson &amp, Fahn) and 11 gender/age matched controls (healthy controls, HC), without concurrent psychiatric disorders, were investigated at baseline (T0) for OT plasma levels and social cognition through an extensive battery of neuropsychological tests. Social cognition was also re-examined after two years (T1) in 8 of the 12 patients. Results showed a trend for reduced T0-OT levels in HD vs. HC, mean &plusmn, stardard deviation: 6.5 &plusmn, 2.4 vs. 9.9 &plusmn, 7.2 pg/mL, without reaching statistical significance. At T0, patients showed significantly lower performances than controls at the &ldquo, Faux-Pas&rdquo, and &ldquo, Strange Stories&rdquo, tests (p &lt, 0.05, p &lt, 0.01), a reduced perception of visual emotions (p &lt, 0.01) and verbal stimuli (p &lt, 0.01) was also reported, involving anger, fear, and sadness (p &lt, 0.01). Additionally, in the HD population, OT concentrations positively correlated with T1-performances at NeutralFaux-Pas test (p &lt, 0.05), whereas the cognitive Montreal Cognitive Assessment (MoCA) and Mini Mental State Examination (MMSE) scores positively correlated with psychosocial perception at the &ldquo, and Karolinska Directed Emotional Faces (KDEF) tests (p &lt, 0.05). This study, despite its limitations, supports correlations between OT and HD social cognition, suggesting a possible therapeutic use of this hormone. More subjects and additional body tissues/fluids, such as cerebrospinal fluid, should be investigated to confirm this hypothesis.

Introduction Blood platelets can be considered a reliable peripheral model of presynaptic serotonergic neurons, as they are endowed with a 5-HT reuptake transporter similar to that present in the brain cells (Marazziti et al., 2004). The biological basis of the patophysiology of obsessive-compulsive disorder (OCD) is centered on serotonergic system, although evidences of both dopaminergic and adrenergic systems involvement are consistent (Westenberg et al., 2007). A possible role of second messengers, such as cyclic adenosine monophosphate (cAMP) signaling, in the development of OCD has been recently postulated, although evidences are meager and, in some cases, contradictory (McDougle et al., 1999). The aim of the present study was to explore and to compare the adenylate cyclase (AC) activity either in basal conditions, either after the stimulation by isoprenaline (ISO) in platelets of OCD patients and healthy control subjects. Also, AC activity was measured both in the absence and in the presence of α- and β- adrenoreceptor antagonists. Materials and methods Forty patients (20 men and 20 women, aged between 23 and 34 years; mean±SD: 26.5 ± 4.8) were included in the study. All of them met Diagnostic and Statistic Manual of Mental Disorders 5th edition (DSM-5) criteria for OCD, were not currently depressed, nor had any history of mood disorders or any other comorbid conditions. This group was compared to a similar one, composed by 40 healthy volunteers patients (20 men and 20 women, aged between 21 and 32 years; mean±SD: 24.6 ± 6.3), all of them without familiar or personal history of major psychiatric disorders. The severity of OC symptoms was evaluated by means of the Yale Brown Obsessive-Compulsive Scale (Y-BOCS). Thirty (30) ml of blood were collected from fasting subjects between 8.00-10.00 a.m. to avoid circadian rhythm interference. Results The platelet basal AC activity was similar in OCD patients and healthy subjects. The addition of 10 μM ISO enhanced significantly (p Discussion No difference in the basal AC activity in platelet membranes of healthy subjects and OCD patients was found. The addition of 10 µM ISO to platelet membranes provoked a significant stimulation of the enzyme activity of the same magnitude in the two groups. Our findings suggests that, at our experimental conditions, there is an inhibitory component of ISO effect on platelet AC, due to the agonist interaction with α2 receptors, at its higher concentrations (> 1 μM). These data suggest the presence of a condition of supersensitive β-receptors in platelets of OCD patients that, perhaps, could reflect (or provoke) alterations of the intracellular signaling system mediated by the cAMP and of the related kinases. In conclusion, the results of the present study suggest that abnormal second messenger pathways in OCD may be also related to cathecolamine system disturbances, which might open new therapeutic strategies especially in resistant patients who do not respond to serotonergic medications.

Given the paucity of data on the distribution of serotonin (5-HT) receptors of type 6 (5-HT(6)) in the human brain, the aim of this study was to investigate their distribution in postmortem human prefrontal cortex, striatum and hippocampus by either immunohistochemical or immunofluorescence techniques. The brain samples were obtained from 6 subjects who had died for causes not involving primarily or secondarily the CNS. The 5-HT(6) receptor distribution was explored by the [(125)I]SB-258585 binding to brain membranes followed by immunohistochemical and immunofluorescence evaluations. A specific [(125)I]SB-258585 binding was detected in all the regions under investigation, whilst the content in the hippocampus and cortex being about 10-30 times lower than in the striatum. Immunohistochemistry and double-label immunofluorescence microscopy experiments, carried out in the prefrontal cortex and hippocampus only, since data in the striatum were already published, showed the presence of 5-HT(6) receptors in both pyramidal and glial cells of prefrontal cortex, while positive cells were mainly pyramidal neurons in the hippocampus. The heterogeneous distribution of 5-HT(6) receptors provides a preliminary explanation of how they might regulate different functions in different brain areas, such as, perhaps, brain trophism in the cortex and neuronal firing in the hippocampus. This study, taking into account all the limitations due to the postmortem model used, represents the starting point to explore the 5-HT(6) receptor functionality and its sub-cellular distribution.

L-Tryptophan is the unique protein amino acid (AA) bearing an indole ring: its biotransformation in living organisms contributes either to keeping this chemical group in cells and tissues or to breaking it, by generating in both cases a variety of bioactive molecules. Investigations on the biology of Trp highlight the pleiotropic effects of its small derivatives on homeostasis processes. In addition to protein turn-over, in humans the pathways of Trp indole derivatives cover the synthesis of the neurotransmitter/hormone serotonin (5-HT), the pineal gland melatonin (MLT), and the trace amine tryptamine. The breakdown of the Trp indole ring defines instead the “kynurenine shunt” which produces cell-response adapters as L-kynurenine, kynurenic and quinolinic acids, or the coenzyme nicotinamide adenine dinucleotide (NAD+). This review aims therefore at tracing a “map” of the main molecular effectors in human tryptophan (Trp) research, starting from the chemistry of this AA, dealing then with its biosphere distribution and nutritional value for humans, also focusing on some proteins responsible for its tissue-dependent uptake and biotransformation. We will thus underscore the role of Trp biochemistry in the pathogenesis of human complex diseases/syndromes primarily involving the gut, neuroimmunoendocrine/stress responses, and the CNS, supporting the use of -Omics approaches in this field.

Objective To preliminary investigate the link between the darkness hormone melatonin (MLT) and the pro-hypnotic effectiveness of the atypical antidepressant Trazodone (TRZ) in a group of mood disorder patients suffering of insomnia. Design and methods The study's design comprised: i) the enrolment of insomniac outpatients, ii) baseline (t 0 ) psychiatric and biochemical examinations; iii) the subsequent patients' introduction into a treatment with TRZ for 3–4 weeks, followed by post-therapy re-evaluations (t 1 ). The MLT function was investigated by t 0 /t 1 ELISA determinations of 6-hydroxy-MLT sulfate (6-OH-MLTs) levels in early-morning urines and HPLC analysis of morning MLT serum amount. Concomitantly, TRZ and its metabolite m -chloro-phenylpiperazine ( m- CPP) were measured by HPLC in serum to monitor patients' compliance/metabolism. Results Seventeen insomniac outpatients, displaying mild symptoms of depression/anxiety resistant to antidepressants, completed TRZ therapy (dose:10–20 mg/day, bedtime). Serum TRZ levels (127 ± 57 ng ml − 1 , mean ± SD) confirmed patients' compliance, while the anxiogenic metabolite m- CPP resulting almost undetectable. Moreover, the 6-OH-MLTs output was found increased at t 1 vs. baseline values (t 1 : 58.4 ± 45.02 ng ml − 1 ; t 0 : 28.6 ± 15.8 ng ml − 1 ; mean ± SD, P P 1 : 48.53 ± 50.70 ng ml − 1 ; t 0 : 49.80 ± 66.53 ng ml − 1 ). Morning MLT in serum slightly diminished at t 1 without reaching the statistical significance, not allowing therefore to define the patients' outcome. Conclusions This initial investigation encourages to explore MLT networks as possible correlates of TRZ pro-hypnotic responses.

Objective In this study, we explored the possible relationships between plasma fluvoxamine levels and clinical features and/or response in adult obsessive-compulsive disorder (OCD) patients treated with this drug for 6months. Methods Twenty OCD outpatients of both sexes who were already taking fluvoxamine (mean doseSD: 216.7 � 86.2) for at least 4weeks were included in the study. The severity of OCD was assessed by means of the Yale-Brown obsessive-compulsive scale (Y-BOCS). The fluvoxamine plasma levels were measured by high-performance liquid chromatography analysis. All evaluations were performed after 4weeks (t1) and 6months (t2) of fluvoxamine intake. Results The plasma levels of fluvoxamine remained stable at the two assessment times, with no sex-related differences. Sixteen (80%) patients responded to treatment as shown by the significant (>35%) decrease of the Y-BOCS total score. Men's compulsions improved more than those of women. Significant and positive correlations were detected between fluvoxamine plasma levels at t1 and t2 and the difference (delta) of the Y-BOCS total and compulsion subscale scores between t1 and t2. Another significant, albeit negative, correlation was measured between the difference of the compulsion subscale score and the difference of fluvoxamine levels at t1 and t2. Conclusions These findings underline the potential importance of evaluating fluvoxamine plasma levels in OCD and their relationships with the clinical response that may be gender-related on specific symptoms. Copyright © 2012 John Wiley & Sons, Ltd. key words—fluvoxamine; obsessive-compulsive disorder; plasma levels; drug metabolism; HPLC; Y-BOCS

The aim of this study was to explore the possible relationship between plasma clomipramine and its major metabolite (N-desmethylclomipramine) levels and related parameters, and clinical features in patients with obsessive-compulsive disorder (OCD). Twenty-six outpatients (13 men, 13 women), suffering from OCD were consecutively enrolled in this study. The severity of OCD was assessed by the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). The measurements were taken after 4 weeks and 6 months from the beginning of the treatment. The drug levels were measured by a high-performance liquid chromatography method developed by us. The correlations between biological and clinical parameters were analyzed by means of Spearman's correlation coefficient. The Mann-Whitney test was used for comparing biological and clinical variables between men and women. The results showed that clomipramine levels were related to the doses at the two assessment times. A significant and positive correlation was detected at the beginning between the N-desmethylclomipramine ratio and the Y-BOCS total score; however, this was true only for men, where the similar correlations were measured also with the Y-BOCS subscale. After 6 months of clomipramine, men showed a significant improvement of the compulsions. These findings would highlight the potential impact of assessing clomipramine plasma levels and their relationships with specific symptoms, as well as the influence of the sex on the drug response.

IntroductionA possible role of second messengers, such as cyclic adenosine monophosphate (cAMP) signalling, in the development of obsessive-compulsive disorder (OCD) has been recently postulated.AimsThe aim of the present study was to explore and to compare the adenylate cyclase (AC) activity in both basal conditions and after the stimulation by isoprenaline (ISO) in platelets of OCD patients and healthy control subjects. The AC activity was measured both in the absence and in the presence of α- and β- adrenoreceptor antagonists.Materials and methodsForty patients were included in the study and compared with healthy volunteers. Biological assays were carried out with a method developed by us.ResultsThe basal AC activity was similar in both groups. The addition of 10 μM ISO enhanced significantly (P < .05) platelet basal AC in both groups. A stimulatory response following ISO in all subjects even without α-antagonists was also observed.DiscussionNo difference in the basal AC activity in platelet membranes of healthy subjects and OCD patients was found. Our findings showed that there is an inhibitory component of ISO effect on platelet AC, due to the agonist interaction with α2 receptors, at its higher concentrations (>1 μM), as well as a condition of supersensitive β-receptors. Our study suggests the presence of cathecolamine system disturbances in OCD.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Parkinson’s Disease (PD) and alpha synucleinopathies are multifactorial disorders, which manifest through motor symptoms and non-motor symptoms involving the Central Nervous System (CNS), the Peripheral Nervous System (PNS) and, recently, also the Enteric Nervous System (ENS). The typical hallmarks of alpha synucleinopathies are proteinaceous inclusions of alpha synuclein (αS). In PD they are known as Lewy Bodies (LBs) and Lewy Neurites (LNs), discovered in dopaminergic neurons of substantia nigra (pars compacta) as well as in other regions of the central and peripheral nervous systems. Despite the clear causes which lead to LBs/LNs are still unknown, according to Braak’s theory, these inclusions appear first in PNS to spread, following neuronal innervation, towards the CNS in a spatio- temporal dissemination described in a staging procedure. In line with these observations, several animal models have been used with the purpose to reproduce PD as well as to propose new therapeutic approaches. Different pathways can cooperate to neurodegeneration in PD such as genetic mutations of αS gene, mitochondrial dysfunctions, neuroinflammation. The present review highlights αS as the key-word for PD pathology and alpha synucleinopathies and a main target in PD research. Several therapeutic approaches can be proposed, however all of them are addressed in advanced stages of the pathology. Our focus will be the alteration of αS physiological pathway, which allows to address therapy in early stages at intracellular or extracellular level, such as the use of anti ER-stress compounds and innovative immunotherapy, which could be promising tools to reduce neuronal degeneration and to halt PD progression.

The metabolism of sulfur (S) compounds concurs to the maintain of cell homeostasis and tissue integrity in the human body. Sulfur chemical species act in all cells as anti-oxidant/scavenging agents or regulators of membrane stability/excitability. At the same time, they also exert tissue-dependent functions behaving as protective molecules of the liver and cardiovascular system, as modulators of the immune response, gut activity and CNS neurotransmitter signaling. The involvement of S compounds in human complex, chronic, disabling diseases at multifaceted pathogenesis is actually under investigation: altered levels of S metabolites could be in fact bio-indicators of impaired oxidation state in the body and their unbalance could be risk factors for disease onset. By the present review, we will discuss data from the literature which unearth an altered S biochemistry in human complex illnesses, taking as an example highly invalidating neuropsychiatry and pain perception diseases as autism spectrum disorders (ASD), schizophrenia and fibromyalgia. As well, we will depict herein the utility at applying to this area of the clinical research high resolving -omics strategies in combination with methodological tools which specifically explore S metabolism in patients. The perspectives of these kind of analyses would be the adoption of more valuable, personalized therapeutics protocols and, possibly, an improved bio-monitoring of patients, also including their response to treatments.

The biology of the macro-element sulfur (S) is attracting an ever growing attention concerning cell physiology and human health. Sulfur metabolism works at the interplay between genetics and epigenetic as well as in the maintain of cell redox homeostasis. Indeed, unbalanced levels of S compounds in the body are actually under investigation as vulnerability factors and/or indicators of impaired cell oxidation state in a variety of human diseases. The purpose of this article is to overview some main S metabolic pathways in humans and their relevance in cell physiology and pathology. Since S is an essential nutrient for life, we first present its distribution and significance in the biosphere, focusing then on S metabolic fluxes which encompass S-containing amino acids (S-AAs), as well as sulfoconjugation, the synthesis and release of H2S together the formation of iron-sulfur cluster proteins. Despite the vastness of the topic, we would like to emphasize herein that the study of S networks in human pathology, especially in complex, multi-factorial disorders, deserves greater impulsion and deepening.

Steady-state plasma concentrations of clozapine and norclozapine, its major metabolite, as well as their sum and ratio (norclozapine/clozapine), were evaluated in 50 in- and outpatients taking clozapine and naturalistically recruited. Drug plasma concentrations were measured by means of a reversed-phase high-performance liquid chromatography (RPLC) method with an ultraviolet detection. Daily doses (milligrams per kilogram of body weight) of clozapine correlated positively with clozapine plasma parameters, except with the norclozapine/clozapine ratio, in all patients. When the patients were divided in subgroups with respect to gender, the corresponding plasma concentrations were no longer dose-related in men. A lack of significant correlation was observed also in patients (n=23) co-treated with typical neuroleptics. Conversely, dose-concentration correlations were significant in either smoker or nonsmoker patients. No significant relationship between body weight and clozapine plasma parameters was reported. Further, we observed (1) a trend towards higher medians of clozapine or total analytes in women than those reported in men (P=.09 and .07); (2) no significant difference in plasma levels obtained in subjects younger than 34 years and subjects 34 years old or older; (3) a trend towards higher norclozapine and clozapine plus norclozapine levels (P=.05 and .08) in nonsmoker than smoker patients; (4) no significant difference between clozapine plasma parameters measured in patients co-medicated with typical neuroleptics and in patients receiving clozapine alone.

Although the pharmacological profile of the atypical antipsychotic clozapine has been extensively studied in animal models, little information is available on its effects in the human brain. In particular, much interest is focused on the understanding of clozapine activity on serotonin (5-HT) neurotransmission, particularly on 5-HT receptor of type 1A (5-HT1A) that seems to play a pivotal role in the control of the 5-HT system. The present work, therefore, aimed at evaluating the effects of clozapine and its major metabolite, norclozapine, on the modulation of adenylyl cyclase (AC) velocity via 5-HT1A receptors in human post-mortem brain regions, in particular the prefrontal cortex, hippocampus and raphe nuclei. Concomitantly, the ability of the two compounds to displace the specific binding of the 5-HT1A receptor agonist [3H]-8-hydroxy-(2-di-N-propylamino) tetralin ([3H]-8-OH-DPAT) was evaluated in the same brain areas. The results showed that both clozapine and norclozapine, although with a 20-fold lower affinity, displaced [3H]8-OH-DPAT binding in all of the brain regions analysed, suggesting their interaction with 5-HT1A receptors. At the same time, clozapine and, to a lesser extent, norclozapine were found to inhibit the forskolin (FK)-stimulated AC system, while decreasing cyclic adenosine monophosphate (cAMP) concentrations in the hippocampus only. The receptor characterisation of the clozapine effect on AC observed in the hippocampus by the use of antagonists showed a mixed profile, involving not only the 5-HT1A receptor but also a muscarinic (M) receptor subtype, most likely the M4 one. These findings, while considering all the limitations due to the use of post-mortem tissues, are strongly suggestive of a region-dependent pharmacological action of clozapine in the human brain that may explain its peculiar clinical effects and open up research towards novel targets for future antipsychotic drugs.

The stereoselectivity of the serotonin1A (5-HT1A) receptor compound 8-hydroxy-2(di-N-propylamino)tetralin (8-OH-DPAT) on forskolin-stimulated adenylyl cyclase activity was investigated in membranes from human 5-HT pre-synaptic (raphe nuclei) and post-synaptic (hippocampus and prefrontal cortex) regions of autopsy brains. After sample incubation with agonists and antagonists, results showed that both the racemic mixture of 8-OH-DPAT or its (+) and (-) enantiomers behaved as full agonists in the tested brain regions. Enantiomer potency (EC50, nM) and efficacy (percentage of maximal inhibition, %) values were similar in all regions under investigation. However, some inter and intra-region variations in racemic 8-OH-DPAT potency and efficacy have been observed. In particular, the potency of racemic 8-OH-DPAT was higher in the prefrontal cortex and raphe nuclei than in the hippocampus, where it was in fact lower than either single enantiomers. Agonist effects were competitively reversed by 5-HT1A antagonists, although once again a different profile was revealed in the hippocampus. The data underscores the lack of stereospecificity of 8-OH-DPAT-mediated inhibition of adenylyl cyclase activity in either pre- or post-synaptic human brain regions. Moreover, such results have significant implication, as they support the notion that human 5-HT1A receptors might vary from one brain region to the other.

The saturation parameters and the pharmacological characteristics of the binding of the serotonin 1A (5-HT 1A ) receptor agonist [ 3 H]8-hydroxy-2-(di-N-propylamino)tetralin ([ 3 H]8-OH-DPAT), as well as the effects of nucleotides and divalent cations (Mg 2+ , Mn 2+ ) on it, were compared in some human postmortem brain regions: the main cortical areas, hippocampus and striatum. [ 3 H]8-OH-DPAT labelled a single population of recognition sites with the highest maximal capacity (B max ) in the hippocampus and the lowest affinity in the striatum. Among the various cortical areas, the frontal cortex exhibited the highest B max . The pharmacological profile of the [ 3 H]8-OH-DPAT binding sites was consistent with the labelling of the 5-HT 1A receptor in the hippocampus and cortex, whereas the striatal site shared strong similarity to the presynaptic serotonin transporter. Modulation of [ 3 H]8-OH-DPAT binding by divalent cations and nucleotides was detectable and stable in autopsy brains. In particular, nucleotide effects were area-dependent: guanosine thiotriphosphate (GTPγS) reduced [ 3 H]8-OH-DPAT binding to the same extent in the hippocampus and frontal cortex, while having no effect in the striatum. Divalent cation effects depended also upon the brain area: in the striatum, they inhibited [ 3 H]8-OH-DPAT binding, while stimulating it in the hippocampus and, with less extent, in the frontal cortex. In summary, these findings suggest that the [ 3 H]8-OH-DPAT binding and its modulatory parameters in human brain tissues seem to show similarities but also some differences with respect to those determined in the rat brain. Furthermore, postmortem stability of GTP and divalent cation sensitive 5-HT 1A receptors underlines the need for further studies on the regulatory and functional properties of this receptor in the human brain.

This study aimed at comparing the binding characteristics of [3H]ketanserin, a high-affinity serotonin 2A (5-HT2A) receptor antagonist, in the prefrontal cortex, hippocampus and striatum of human brain post-mortem. The results indicated the presence of a single population of binding sites in all the regions investigated, with no statistical difference in maximum binding capacity (Bmax) or dissociation constant (Kd) values. The pharmacological profile of [3H]ketanserin binding was consistent with the labeling of the 5-HT2A receptor, since it revealed a competing drug potency ranking of ketanserin = spiperone > clozapine = haloperidol > methysergide > mesulergine > 5-HT. In conclusion, the 5-HT2A receptor, as labeled by [3H]ketanserin, would seem to consist of a homogenous population of binding sites and to be equally distributed in human prefronto-cortical, limbic and extrapyramidal structures.

Background Serotonin (5-HT) is a well-known modulator of eating behavior. However, the molecular mechanisms linking its action to body weight balance have been only partially elucidated. Since platelets are a suitable peripheral model to study 5-HT transport, metabolism and release, we herein evaluated the expression of the platelet 5-HT re-uptake system (SERT) by [3H]-paroxetine binding assay. A cohort of 114 unrelated individuals (34 males, 80 females; age, mean ± SD: 38.57 ± 12.47 years) without major psychiatric disorders, was recruited following a naturalistic design regarding age or gender and classified accordingly to their body mass index (BMI). Subjects were divided into 5 groups: normal-weight (NW), overweight (OW) and grade I-III obese (OB) individuals. For gender analyses, data were transformed into [3H]-paroxetine density (Bmax)/BMI ratios to overcome both the disparity of women vs. men number and anthropometric differences between sexes. Results [3H]-paroxetine Bmax (SERT density, fmol/mg proteins) was reduced in platelet membranes of grade II (p 35 Kg/m2) confirms the involvement of 5-HT system in body weight gain. Moreover, this findings may help to elucidate those monoamine-endocrine networks acting on fat storage, adipocyte signaling and energy balance. Targeting 5-HT/5-HT-related markers will possibly uncover the existence of human obesity subtypes.